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  • 1.
    Abadi, Imam
    et al.
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Hardiana, Tiara Oktavia
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Imron, Chairul
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Fitriyanah, Dwi Nur
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Jani, Yahya
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Abdullah, Kamaruddin
    Darma Persada University, Indonesia.
    Design of Adaptive Neuro-Fuzzy Inference Control Based One-Axis Solar Tracker on Battery Charging System2020Inngår i: E3S Web of Conferences, EDP Sciences, 2020, Vol. 190, s. 1-15, artikkel-id 00015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The photovoltaic (PV) panel can produce electrical energy that is very environmentally friendly and easy to use. The use of PV panels is suitable for supplying peak loads or at night using batteries as energy storage. However, the battery needs to manage for control, and the battery can last long. The solution to battery management problems is through research about the battery charging system. The DC-DC converter used is the Single Ended Primary Inductance Converter (SEPIC) type. Voltage Control of the battery charging using Adaptive Neuro-Fuzzy Inference System (ANFIS). In the simulation of bright conditions, ANFIS controls can track the charging point set point and obtain a voltage response with a rise time of 0.0028 s, a maximum overshoot of 0.027 %, a peak time of 0.008 s, and a settling time of 0.0193 s. When charging a solar tracker, PV battery gets a 0.25 % increase compared to a fixed PV panel. PV solar tracker can follow the direction of the sun's position. The irradiation value and maximum temperature affect the input voltage and input current that enters the converter. © The Authors, published by EDP Sciences, 2020.

  • 2.
    Abadi, Imam
    et al.
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Uyuniyah, Qurrotul
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Fitriyanah, Dwi Nur
    Institut Teknologi Sepuluh Nopember, Indonesia.
    Jani, Yahya
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Abdullah, Kamaruddin
    Darma Persada University, Indonesia.
    Performance Study of Maximum Power Point Tracking (MPPT) Based on Type-2 Fuzzy Logic Controller on Active Dual Axis Solar Tracker2020Inngår i: E3S Web of Conferences, EDP Sciences, 2020, Vol. 190, s. 1-16, artikkel-id 00016Konferansepaper (Fagfellevurdert)
    Abstract [en]

    World energy consumption increases with time, so that occur an energy imbalance. Many breakthroughs have developed to utilize renewable energy. The photovoltaic system is one of the easy-to-use renewable energies. The power conversion from PV fixed is still low, so the PV system is designed using the active dual-axis solar tracker. The PV tracker position can be adjusted to change the sun position to get maximum efficiency. The active dual-axis solar tracker system is integrated with the maximum power point tracking (MPPT) algorithm to keep PV operating at a maximum power point even though input variations change. The active dual-axis solar tracker system integrated with the maximum power point tracking (MPPT) algorithm to keep PV operating at a maximum power point even though input variations change. Tracking test simulation had done by comparing the output power of a fixed PV system with the active dual-axis solar tracker. Type-2 fuzzy logic based MPPT successfully increased the average output power by 10.48 % with the highest increase of 17.48 % obtained at 15:00 West Indonesia Time (GMT+7). The difference in power from a fixed PV system with the active dual-axis solar tracker of 36.08 W is from the output power worth 206.3 to 242.4 W. © The Authors, published by EDP Sciences, 2020.

  • 3.
    Abarca-Guerrero, Lilliana
    et al.
    Univ Tecnol Eindhoven, Netherlands.
    Maas, Ger
    Univ Tecnol Eindhoven, Netherlands.
    Hogland, William
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Desafíos en la gestión de residuos sólidos para las ciudades de países en desarrollo [Solid waste management challenges for cities in developing countries]2015Inngår i: Tecnología en Marcha, ISSN 0379-3982, Vol. 28, nr 2, s. 141-168Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Solid waste management is a challenge for the cities' authorities in developing countries mainly due to the increasing generation of waste, the burden posed on the municipal budget as a result of the high costs associated to its management, the lack of understanding over a diversity of factors that affect the different stages of waste management and linkages necessary to enable the entire handling system functioning. An analysis of literature on the work done and reported mainly in publications from 2005 to 2011, related to waste management in developing countries, showed that few articles give quantitative information. The analysis was conducted in two of the major scientific journals, Waste Management Journal and Waste Management and Research. The objective of this research was to determine the stakeholders' action/behavior that have a role in the waste management process and to analyze influential factors on the system, in more than thirty urban areas in 22 developing countries in 4 continents. A combination of methods was used in this study in order to assess the stakeholders and the factors influencing the performance of waste management in the cities. Data was collected from scientific literature, existing data bases, observations made during visits to urban areas, structured interviews with relevant professionals, exercises provided to participants in workshops and a questionnaire applied to stakeholders. Descriptive and inferential statistic methods were used to draw conclusions. The outcomes of the research are a comprehensive list of stakeholders that are relevant in the waste management systems and a set of factors that reveal the most important causes for the systems' failure. The information provided is very useful when planning, changing or implementing waste management systems in cities.

  • 4.
    Abreu, Clare I.
    et al.
    MIT, USA;Stanford Univ, USA.
    Dal Bello, Martina
    MIT, USA.
    Bunse, Carina
    University of Gothenburg, Sweden.
    Pinhassi, Jarone
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Gore, Jeff
    MIT, USA.
    Warmer temperatures favor slower-growing bacteria in natural marine communities2023Inngår i: Science Advances, E-ISSN 2375-2548, Vol. 9, nr 19, artikkel-id 26eade8352Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Earth's life-sustaining oceans harbor diverse bacterial communities that display varying composition across time and space. While particular patterns of variation have been linked to a range of factors, unifying rules are lacking, preventing the prediction of future changes. Here, analyzing the distribution of fast- and slowgrowing bacteria in ocean datasets spanning seasons, latitude, and depth, we show that higher seawater temperatures universally favor slower-growing taxa, in agreement with theoretical predictions of how temperaturedependent growth rates differentially modulate the impact of mortality on species abundances. Changes in bacterial community structure promoted by temperature are independent of variations in nutrients along spatial and temporal gradients. Our results help explain why slow growers dominate at the ocean surface, during summer, and near the tropics and provide a framework to understand how bacterial communities will change in a warmer world.

  • 5.
    Abromaitis, V.
    et al.
    Kaunas Univ Technol, Lithuania ; Wetsus, European Ctr Excellence Sustainable Water Technol, Netherlands.
    Racys, V.
    Kaunas Univ Technol, Lithuania.
    van der Marel, P.
    WLN, Netherlands.
    Ni, Gaofeng
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Dopson, Mark
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Wolthuizen, A. L.
    Wageningen Univ, Netherlands.
    Meulepas, R. J. W.
    Wetsus, European Ctr Excellence Sustainable Water Technol, Netherlands.
    Effect of shear stress and carbon surface roughness on bioregeneration and performance of suspended versus attached biomass in metoprolol-loaded biological activated carbon systems2017Inngår i: Chemical Engineering Journal, ISSN 1385-8947, E-ISSN 1873-3212, Vol. 317, s. 503-511Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The bioregeneration of activated carbon (AC) in biological activated carbon (BAC) systems is limited by sorption-desorption hysteresis and transport between the adsorbent and biomass. In this study, we investigated these limitations and whether a biofilm covering the AC surface is required. Consequently, BAC reactors were operated at different shear stress and AC surface smoothness, since this may affect biofilm formation. The experiments were carried out in BAC and blank reactors treating synthetic wastewater containing the pharmaceutical metoprolol. After start-up, all reactors removed metoprolol completely; however, after 840 h the removal dropped due to saturation of the AC. In the blank reactors, the removal dropped to 0% while in the BAC reactors removal recovered to >99%, due to increased biological activity. During the initial phase, the metoprolol was adsorbed, rather than biodegraded. At the end, the AC from the BAC reactors had higher pore volume and sorption capacity than from the blank reactors, showing that the AC had been bioregenerated. At high shear (G = 25 s(-1)), the rough AC granules (R-a = 13 mu m) were covered with a 50-400 gm thick biofilm and the total protein content of the biofilm was 2.6 mg/gAC, while at lower shear (G = 8.8 s(-1)) the rough AC granules were only partly covered. The biofilm formation at lower shear (G = 8.8 s(-1)) on smooth AC granules (R-a = 1.6 mu m) was negligible. However, due to the presence of suspended biomass the reactor performance or bioregeneration were not reduced. This showed that direct contact between the AC and biomass was not essential in mixed BAC systems. The microbial analyses of the suspended biomass and the biofilm on AC surface indicated that metoprolol was mainly biodegraded in suspension. (C) 2017 Elsevier B.V. All rights reserved.

  • 6.
    Abudaya, Mohammed
    et al.
    Natl Res Ctr, Palestine.
    Ulman, Aylin
    Univ British Columbia, Canada.
    Salah, Jehad
    Minist Agr, Palestine.
    Fernando, Daniel
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Manta Trust, UK;Blue Resources Trust, Sri Lanka.
    Wor, Catarina
    Univ British Columbia, Canada.
    di Sciara, Giuseppe Notarbartolo
    Tethys Res Inst, Italy.
    Speak of the devil ray (Mobula mobular) fishery in Gaza2018Inngår i: Reviews in Fish Biology and Fisheries, ISSN 0960-3166, E-ISSN 1573-5184, Vol. 28, nr 1, s. 229-239Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Little is known about the giant devil ray (Mobula mobular), an endangered species endemic to the Mediterranean. Gaza is the only region where this species is targeted, hence, this fishery was studied to address the knowledge gap on fishery interactions, species behavior, and life-history traits. Devil rays have been frequenting this maritime area for at least the past 50 years for a short window from February to April. Landings are reported from 2005 to 2016, along with disc-width (DW) measurements for recent years. A total of 304 M. mobular (over 90% males) were landed in Gaza from 2014 to 2016, most which were mature and appeared to be mating (over 90% of males had sperm-filled claspers), providing critical insight that this area may serve as a mating ground. Yearly landings are shown here to closely match the allowed fishing distance from shore, which changes regularly, indicating that the rays are normally caught between 6 and 12 n.m. offshore. Width-weight conversion parameters are calculated for the first time for this species: a = 2.68 x 10(-6) and b = 4.39. Fresh protein drives this local fishery, as food security is a major issue. An export market for gill plates was reported intermittently, and is no longer possible due to strict trade restrictions. We highlight the lack of awareness of fishers regarding the IUCN's Red List 'Endangered' status of devil rays, and stress the urgent need for national protection of this species, particularly due to the species' very slow life-history traits and probable usage of this area as a mating ground.

  • 7.
    Acuna, Lillian G.
    et al.
    Fundación Ciencia & Vida, Chile ; Universidad Andres Bello, Chile.
    Pablo Cardenas, Juan
    Fundación Ciencia & Vida, Chile ; Universidad Andres Bello, Chile.
    Covarrubias, Paulo C.
    Fundación Ciencia & Vida, Chile ; Universidad Andres Bello, Chile.
    Jose Haristoy, Juan
    Fundación Ciencia & Vida, Chile.
    Flores, Rodrigo
    Fundación Ciencia & Vida, Chile.
    Nuñez, Harold
    Fundación Ciencia & Vida, Chile.
    Riadi, Gonzalo
    Universidad de Talca, Chile.
    Shmaryahu, Amir
    Fundación Ciencia & Vida, Chile.
    Valdes, Jorge
    Center for Systems Biotechnology, Chile.
    Dopson, Mark
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Rawlings, Douglas E.
    University of Stellenbosch, South Africa.
    Banfield, Jillian F.
    University of California, USA.
    Holmes, David S.
    Fundación Ciencia & Vida, Chile ; Universidad Andres Bello, Chile.
    Quatrini, Raquel
    Fundación Ciencia & Vida, Chile ; Universidad Andres Bello, Chile.
    Architecture and Gene Repertoire of the Flexible Genome of the Extreme Acidophile Acidithiobacillus caldus2013Inngår i: PLOS ONE, E-ISSN 1932-6203, Vol. 8, nr 11, artikkel-id e78237Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Acidithiobacillus caldus is a sulfur oxidizing extreme acidophile and the only known mesothermophile within the Acidithiobacillales. As such, it is one of the preferred microbes for mineral bioprocessing at moderately high temperatures. In this study, we explore the genomic diversity of A. caldus strains using a combination of bioinformatic and experimental techniques, thus contributing first insights into the elucidation of the species pangenome. Principal Findings: Comparative sequence analysis of A. caldus ATCC 51756 and SM-1 indicate that, despite sharing a conserved and highly syntenic genomic core, both strains have unique gene complements encompassing nearly 20% of their respective genomes. The differential gene complement of each strain is distributed between the chromosomal compartment, one megaplasmid and a variable number of smaller plasmids, and is directly associated to a diverse pool of mobile genetic elements (MGE). These include integrative conjugative and mobilizable elements, genomic islands and insertion sequences. Some of the accessory functions associated to these MGEs have been linked previously to the flexible gene pool in microorganisms inhabiting completely different econiches. Yet, others had not been unambiguously mapped to the flexible gene pool prior to this report and clearly reflect strain-specific adaption to local environmental conditions. Significance: For many years, and because of DNA instability at low pH and recurrent failure to genetically transform acidophilic bacteria, gene transfer in acidic environments was considered negligible. Findings presented herein imply that a more or less conserved pool of actively excising MGEs occurs in the A. caldus population and point to a greater frequency of gene exchange in this econiche than previously recognized. Also, the data suggest that these elements endow the species with capacities to withstand the diverse abiotic and biotic stresses of natural environments, in particular those associated with its extreme econiche.

  • 8.
    Adbo, Karina
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Emergent Chemistry: Using Visualizations to Develop Abstract Thinking and a Sense of Scale Within the Preschool Setting2022Inngår i: Active Learning - Research and Practice for STEAM and Social Sciences Education / [ed] Ortega-Sánchez, Delfín, IntechOpen , 2022Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    This chapter is a summary of 5-years of research regarding children’s emerging abstract concepts. A longitudinal study focusing on children’s conversations during a series of activities with a chemistry focus was designed and implemented. Results show that practical experience with magnifying glasses, microscopes, and the deconstruction of several items did not provide enough backdrop for the children to imagine what an even smaller world would look like. Instead, the children applied their experiences from the macroscopic world to describe what they saw. It was not until aminations, zooming in from the macroscopic to the atomic and molecular levels were used that the children’s concept of small began to develop. Results show that the next stage of concept development, besides using descriptions from everyday experiences was the realization these were new experiences, that it was in fact something new they were seeing. Animation technology also helped the children realize that atoms and molecules are everywhere in everything, suggesting that the time elapsed between the transition from the macroscopic level to the submicroscopic level also provided the children with a sense of scale.

    Fulltekst (pdf)
    fulltext
  • 9.
    Adbo, Karina
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Emergent Science- A Swedish perspective2019Konferansepaper (Annet (populærvitenskap, debatt, mm))
  • 10.
    Adbo, Karina
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Vidal Carulla, Clara
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Designing play-based learning activities for a preschool setting2018Inngår i: EESERA, 2018Konferansepaper (Fagfellevurdert)
  • 11.
    Adbo, Karina
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Vidal Carulla, Clara
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Designing play-based learning chemistry activities in the preschool environment2019Inngår i: Chemistry Education Research and Practice, E-ISSN 1756-1108, Vol. 20, nr 3, s. 542-553Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study focuses on the design of play-based learning activities for chemistry in preschool. Viewing chemistry as a part of our past and present culture instead of as a subject, provides the backdrop for a more holistic approach to chemistry within this specific environment. A cultural-historical perspective, together with scaffolding, emergent science skills and sustained shared thinking, made up the framework for the design of the learning activities. Results show that when scaffolding and emergent science skills are used within the design, they provide good support for both the content and the teacher in the actual learning situation. Working with scaffolding was also beneficial for professional development. However, for a progressive and inclusive activity design, it is essential to take into account aspects of the immediate environment and methods for direct evaluation.

  • 12.
    Adbo, Karina
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Vidal Carulla, Clara
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Learning About Science in Preschool: Play-Based Activities to Support Children's Understanding of Chemistry Concepts2020Inngår i: International Journal of Early Childhood, ISSN 0020-7187, E-ISSN 1878-4658, Vol. 52, nr 1, s. 17-35Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The study explores children's emerging understanding of an important science concept in chemistry. Play-based learning activities were designed for children to experience and imagine the concept of 'small' as used in chemistry, moving from the visually experienced level of 'small' towards more imaginative understandings. Data were collected through visual ethnography. Analyses of six vignettes of conversations between children and the teacher illustrate development of children's understanding of the focus concept. Deconstruction of everyday items familiar to the children and visual computer animations provided experiences that enabled children to transition from a macro-level of understanding to visualise the molecular/atomic level to differentiate between macro- and micro-understandings of 'small'. A process of 'sustained shared thinking' could describe the teaching/learning processes evident in the children's and teacher's conversations. The analyses suggest that sustained and shared conversations between children and teachers should stem from children's everyday experiences. ResumeL'etude explore chez les enfants la comprehension emergente d'un concept scientifique important en chimie. Des activites d'apprentissage basees sur le jeu ont ete concues pour que les enfants experimentent et imaginent le concept du 'petit' tel qu'il est utilise en chimie, en passant de la decouverte visuelle au niveau du 'petit' vers des comprehensions plus imaginatives. Des donnees ont ete recueillies par le biais de l'ethnographie visuelle. L'analyse de six vignettes de conversations entre les enfants et l'enseignant illustre le developpement chez les enfants de la comprehension du concept examine. La deconstruction d'objets quotidiens familiers pour les enfants et d'animations visuelles sur ordinateur ont fourni des experiences qui ont permis aux enfants de passer d'un niveau de comprehension macro a une visualisation du niveau moleculaire /atomique, et de faire la difference entre les comprehensions macro et micro du 'petit'. Un processus de 'pensee partagee soutenue' pourrait decrire les processus d'enseignement /apprentissage evidents dans les conversations entre enfants et enseignants. Les analyses suggerent que les conversations soutenues et partagees entre les enfants et les enseignants devraient decouler des experiences quotidiennes des enfants. ResumenEl presente estudio explora la comprension reciente de los ninos de un importante concepto de ciencia en el campo de la quimica. Se disenaron actividades ludicas de aprendizaje para que los ninos experimentaran e imaginaran el concepto de tamano "pequeno" segun se utiliza en el campo de la quimica, alternando entre el nivel de experiencia visual del concepto "pequeno" hasta una comprension mas imaginativa. Se recolecto informacion por medio de etnografia visual. Analisis de seis fragmentos de conversaciones entre los ninos y el educador ilustraron el desarrollo de la comprension de los ninos del concepto principal. La deconstruccion de elementos cotidianos comunes para los ninos y las animaciones visuales computarizadas brindaron experiencias que les permitieron a los ninos navegar desde un nivel macro de comprension a visualizar el nivel molecular/atomico, asi como diferenciar entre la comprension macro y micro del concepto "pequeno". Los procesos de ensenanza/aprendizaje que se evidencian en las conversaciones entre ninos y educadores se pueden describir mediante un proceso de "constante pensamiento comun". Los analisis sugieren que conversaciones constantes y compartidas entre ninos y educadores deben emanar de las experiencias cotidianas de los infantes.

  • 13.
    Adolfsson, Oscar
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Consequences on population dynamics following regained connectivity in pike (Esox lucius) spawning location2020Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Distributional movements of subpopulations may act as a buffer to prevent the loss of a species in a certain area. However, within subpopulations adaptations may evolve that makes the inhabitants of a certain habitat to better cope with prevailing environmental conditions. If such traits are related to reproduction, they may reduce the opportunity of gene exchange between other subpopulations. Also, a lack of adaptations to a specific habitat may be what prevents a group of individuals, arriving from an adjacent habitat, to successfully colonize an area where a previous subpopulation has been lost.This is the report from a field study conducted in the wetland Lake Långsjön, that in 2018 was restored in order to promote the recruitment of anadromous pike (Esox lucius) to the Baltic Sea. Commonly, wetlands that are restored to promote anadromous pike recruitment, are constructed so that they enable spawning migration from the sea towards the wetland and juvenile emigration towards the sea only. In that sense Lake Långsjön is different, from other wetlands restored for the same purpose, due to that it is connected to both the Baltic Sea and an upstream located freshwater lake. By quantifying the migration of pike (spawners and juveniles) in both directions I explore the consequences that the regained connectivity between the Lake Långsjön and the coast may have on the population dynamics within this wetland; (i) whether it is potentially influenced by allowing mixture between pike with different migratory strategies for spawning (anadromous and potamodromous), (ii) what drivers there are of pike fry emigration and how they may influence the pike fry emigration route and (iii) whether or not the pike of potamodromous origin, resident in the upstream located lake, may work as a source, providing the Baltic Sea with pike juveniles. Pike spawners arriving in the wetland were caught in traps between March - April. Pike fry were caught withing the wetland with fyke nets and by netting. Emigrating pike fry were caught in fyke nets. Findings suggest that spawning migration patterns do not differ between anadromous and potamodromous pike. However, the spawners arriving from the Baltic Sea I suggested are to be composed by offspring of potamodromous origin, possibly hatched during the previous season, and that they as juveniles swam downstream. This, in turn, indicates that the potamodromous stock can help establish an anadromous stock in the Baltic Sea. Still, due to the observation of pike fry displaying an emigration behaviour upstream, origin is identified as a factor that may influence the pike fry emigration route. Also, this emigration pattern seems to indicate a heritable trait that has not been described before among pike, that of downstream spawning. The restoration of the wetland and the regained connectivity is key, both for the ability to restock the Baltic Sea with pike juveniles but also to ensure the conservation of a fascinating stock of pike exhibiting a unique spawning strategy

    Fulltekst (pdf)
    fulltext
  • 14.
    Agestam, Elin
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Bedömningsgrunder vid omhändertagande av hund: En jämförelse mellan sex länsstyrelser i Sverige2022Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    The dog brings great joy and is of great benefit to humans, for example as a companion dog, hunting dog, service dog and assistance dog. In some cases, dogs cause problems and society must then intervene. The Act of Supervision of Dogs and Cats aims at preventing damage and significant inconvenience that can be caused by dogs and cats. If a dog causes damage or nuisance according to The Act of Supervision of Dogs and Cats, the law can support a decision to seize a dog by the County Administrative Board or the Police Authority. Often the dog is seized because it has bitten another dog, human or other animal.

    In case of seizure, an investigation must be carried out by the County Administrative Board to assess the dog's mental and physical status. The Police inspector performs a mental examination of the dog, and a Veterinarian examines the dog's physical status. The County Administrative Board then decides whether the dog should be returned to its owner, rehomed, or euthanized. This study has examined the county administrations' work in Norrbotten, Skåne, Stockholm, Västerbotten, Västmanland and Västra Götaland. A total of 89 dogs were seized in the six counties, between the years 2019–2021, 53 male dogs (approx. 60%) and 36 female dogs (approx. 40%). Euthanasia was the most frequently performed measure, 42 dogs were euthanized. Others were returned or rehomed. In general, all six county administrations carry out careful investigations, but a clear difference between them is how often the county administrations follow the police's proposed measures. The county administrative boards decide on euthanasia more often, 42 out of 89 times (47%), than the police give suggestions on euthanasia, 34 out of 89 times (38%).

    The new regulation, which entered into force on February 1, 2022, makes it possible for the county administrations to be even more thorough in their investigations of dogs in care. In addition to a mental examination and veterinary examination, the county administrations must also request a statement from the kennel about the dog's behaviour towards people and animals.

    Fulltekst (pdf)
    Elin_Agestam
  • 15.
    Aguilera, Anabella
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Alegria Zufia, Javier
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Bas Conn, Laura
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Gurlit, Leandra
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Śliwińska‐Wilczewska, Sylwia
    Mount Allison University, Canada;University of Gdansk, Poland.
    Budzałek, Gracjana
    University of Gdansk, Poland.
    Lundin, Daniel
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Pinhassi, Jarone
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Legrand, Catherine
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Halmstad University, Sweden.
    Farnelid, Hanna
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Ecophysiological analysis reveals distinct environmental preferences in closely related Baltic Sea picocyanobacteria2023Inngår i: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 25, nr 9, s. 1674-1695Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cluster 5 picocyanobacteria significantly contribute to primary productivity in aquatic ecosystems. Estuarine populations are highly diverse and consist of many co-occurring strains, but their physiology remains largely understudied. In this study, we characterized 17 novel estuarine picocyanobacterial strains. Phylogenetic analysis of the 16S rRNA and pigment genes (cpcBandcpeBA) uncovered multiple estuarine and freshwater-related clusters and pigment types. Assays with five representative strains (three phycocyanin rich and two phycoerythrin rich) under temperature (10–30°C), light(10–190 μmol  photons  m-2s-1), and salinity (2–14  PSU) gradients revealed distinct growth optima and tolerance, indicating that genetic variability was accompanied by physiological diversity. Adaptability to environmental conditions was associated with differential pigment content and photosynthetic performance. Amplicon sequence variants at a coastal and an offshore station linked population dynamics with phylogenetic clusters, supporting that strains isolated in this study represent key ecotypes within the Baltic Sea picocyanobacterial community. The functional diversity found within strains with the same pigment type suggests that understanding estuarine picocyanobacterial ecology requires analysis beyond the phycocyanin and phycoerythrin divide. This new knowledge of the environmental preferences in estuarine picocyanobacteria is important for understanding and evaluating productivity in current and future ecosystems.

  • 16.
    Aguilera, Anabella
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Almanza, Viviana
    Univ Concepcion, Chile.
    Haakonsson, Signe
    Univ Republica, Uruguay.
    Palacio, Hilda
    Univ CES, Colombia.
    Rodas, Gilberto A. Benitez
    Univ Nacl Asuncion, Paraguay.
    Barros, Mario U. G.
    Univ Fed Ceara, Brazil;Water Resources Management Co Ceara, Brazil.
    Capelo-Neto, Jose
    Univ Fed Ceara, Brazil.
    Urrutia, Roberto
    Univ Concepcion, Chile.
    Aubriot, Luis
    Univ Republica, Uruguay.
    Bonilla, Sylvia
    Univ Republica, Uruguay.
    Cyanobacterial bloom monitoring and assessment in Latin America2023Inngår i: Harmful Algae, ISSN 1568-9883, E-ISSN 1878-1470, Vol. 125, artikkel-id 102429Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cyanobacterial blooms have serious adverse effects on human and environmental health. In Latin America, one of the main world's freshwater reserves, information on this phenomenon remains sparse. To assess the current situation, we gathered reports of cyanobacterial blooms and associated cyanotoxins in freshwater bodies from South America and the Caribbean (Latitude 22 degrees N to 45 degrees S) and compiled the regulation and monitoring procedures implemented in each country. As the operational definition of what is a cyanobacterial bloom remains controversial, we also analyzed the criteria used to determine the phenomena in the region. From 2000 to 2019, blooms were reported in 295 water bodies distributed in 14 countries, including shallow and deep lakes, reservoirs, and rivers. Cyanotoxins were found in nine countries and high concentrations of microcystins were reported in all types of water bodies. Blooms were defined according to different, and sometimes arbitrary criteria including qualitative (changes in water color, scum presence), quantitative (abundance), or both. We found 13 different cell abundance thresholds defining bloom events, from 2 x 10(3) to 1 x 10(7) cells mL(-1). The use of different criteria hampers the estimation of bloom occurrence, and consequently the associated risks and economic impacts. The large differences between countries in terms of number of studies, monitoring efforts, public access to the data and regulations regarding cyanobacteria and cyanotoxins highlights the need to rethink cyanobacterial bloom monitoring, seeking common criteria. General policies leading to solid frameworks based on defined criteria are needed to improve the assessment of cyanobacterial blooms in Latin America. This review represents a starting point toward common approaches for cyanobacterial monitoring and risk assessment, needed to improve regional environmental policies.

  • 17.
    Aguilera, Anabella
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Distéfano, Ayelén
    Universidad Nacional de Mar del Plata, Argentina.
    Jauzein, Cécile
    Ifremer, France.
    Correa-Aragunde, Natalia
    Universidad Nacional de Mar del Plata, Argentina.
    Martinez, Dana
    Universidad Nacional de La Plata, Argentina.
    Martin, María Victoria
    Fundación para InveUniversidad Nacional de Mar del Plata, Argentina.
    Sueldo, Daniela J
    Norwegian University of Science and Technology, Norway.
    Do photosynthetic cells communicate with each other during cell death? From cyanobacteria to vascular plants2022Inngår i: Journal of Experimental Botany, ISSN 0022-0957, E-ISSN 1460-2431, Vol. 73, nr 22, s. 7219-7242Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    As in metazoans, life in oxygenic photosynthetic organisms relies on the accurate regulation of cell death. During development and in response to the environment, photosynthetic cells activate and execute cell death pathways that culminate in the death of a specific group of cells, a process known as regulated cell death (RCD). RCD control is instrumental, as its misregulation can lead to growth penalties and even the death of the entire organism. Intracellular molecules released during cell demise may act as ‘survival’ or ‘death’ signals and control the propagation of cell death to surrounding cells, even in unicellular organisms. This review explores different signals involved in cell-cell communication and systemic signalling in photosynthetic organisms, in particular Ca2+, reactive oxygen species, lipid derivates, nitric oxide, and eATP. We discuss their possible mode-of-action as either ‘survival’ or ‘death’ molecules and their potential role in determining cell fate in neighbouring cells. By comparing the knowledge available across the taxonomic spectrum of this coherent phylogenetic group, from cyanobacteria to vascular plants, we aim at contributing to the identification of conserved mechanisms that control cell death propagation in oxygenic photosynthetic organisms 

    Fulltekst tilgjengelig fra 2024-11-01 17:54
  • 18.
    Aguilera, Anabella
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Klemencic, Marina
    University of Ljubljana, Slovenia.
    Sueldo, Daniela J.
    University of Warwick, UK.
    Rzymski, Piotr
    Poznan University of Medical Sciences, Poland;Universal Scientific Education and Research Network (USERN), Poland.
    Giannuzzi, Leda
    National University of La Plata, Argentina.
    Martin, Maria Victoria
    CONICET Instituto de Investigaciones en Biodiversidad y Biotecnología (INBIOTEC), Argentina;Fundación para Investigaciones Biológicas Aplicadas (FIBA), Argentina.
    Cell death in Cyanobacteria: current understanding and recommendations for a consensus on its nomenclature2021Inngår i: Frontiers in Microbiology, E-ISSN 1664-302X, Vol. 12, s. 1-15, artikkel-id 631654Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Cyanobacteria are globally widespread photosynthetic prokaryotes and are major contributors to global biogeochemical cycles. One of the most critical processes determining cyanobacterial eco-physiology is cellular death. Evidence supports the existence of controlled cellular demise in cyanobacteria, and various forms of cell death have been described as a response to biotic and abiotic stresses. However, cell death research in this phylogenetic group is a relatively young field and understanding of the underlying mechanisms and molecular machinery underpinning this fundamental process remains largely elusive. Furthermore, no systematic classification of modes of cell death has yet been established for cyanobacteria. In this work, we analyzed the state of knowledge in the field of cyanobacterial cell death. Based on that, we propose unified criterion for the definition of accidental, regulated, and programmed forms of cell death in cyanobacteria based on molecular, biochemical, and morphologic aspects following the directions of Nomenclature Committee on Cell Death (NCCD). With this, we aim to provide a guide to standardize the nomenclature related to this topic in a precise and consistent manner, which will facilitate further ecological, evolutionary and applied research in the field of cyanobacterial cell death

    Fulltekst (pdf)
    fulltext
  • 19.
    Aguirre-Gutierrez, Jesus
    et al.
    Naturalis Biodivers Ctr, Netherlands;Univ Oxford, UK;Univ Amsterdam, Netherlands.
    WallisDeVries, Michiel F.
    De Vlinderstichting, Netherlands;Wageningen Univ, Netherlands.
    Marshall, Leon
    Naturalis Biodivers Ctr, Netherlands;Univ Namur, Belgium.
    van't Zelfde, Maarten
    Naturalis Biodivers Ctr, Netherlands;Leiden Univ, Netherlands.
    Villalobos-Arambula, Alma R.
    Univ Guadalajara, Mexico.
    Boekelo, Bastiaen
    Wageningen Univ & Res, Netherlands.
    Bartholomeus, Harm
    Wageningen Univ & Res, Netherlands.
    Franzén, Markus
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). UFZ, Helmholtz Ctr Environm Res, Germany.
    Biesmeijer, Jacobus C.
    Naturalis Biodivers Ctr, Netherlands;Leiden Univ, Netherlands.
    Butterflies show different functional and species diversity in relationship to vegetation structure and land use2017Inngår i: Global Ecology and Biogeography, ISSN 1466-822X, E-ISSN 1466-8238, Vol. 26, nr 10, s. 1126-1137Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    AimBiodiversity is rapidly disappearing at local and global scales also affecting the functional diversity of ecosystems. We aimed to assess whether functional diversity was correlated with species diversity and whether both were affected by similar land use and vegetation structure drivers. Better understanding of these relationships will allow us to improve our predictions regarding the effects of future changes in land use on ecosystem functions and services. LocationThe Netherlands. MethodsWe compiled a dataset of c.3 million observations of 66 out of 106 known Dutch butterfly species collected across 6,075 sampling locations during a period of 7 years, together with very high-resolution maps of land use and countrywide vegetation structure data. Using a mixed-effects modelling framework, we investigated the relationship between functional and species diversity and their main land use and vegetation structure drivers. ResultsWe found that high species diversity does not translate into high functional diversity, as shown by their different spatial distribution patterns in the landscape. Functional and species diversity are mainly driven by different sets of structural and land use parameters (especially average vegetation height, amount of vegetation between 0.5 and 2m, natural grassland, sandy soils vegetation, marsh vegetation and urban areas). We showed that it is a combination of both vegetation structural characteristics and land use variables that defines functional and species diversity. Main conclusionsFunctional diversity and species diversity of butterflies are not consistently correlated and must therefore be treated separately. High functional diversity levels occurred even in areas with low species diversity. Thus, conservation actions may differ depending on whether the focus is on conservation of high functional diversity or high species diversity. A more integrative analysis of biodiversity at both species and trait levels is needed to infer the full effects of environmental change on ecosystem functioning.

  • 20.
    Ahlberg, Louise
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Molecular sexing and species determination of the Sylvia cantillans complex.2022Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Abstract

    The Sylvia cantillans complex is a collection of closely related passerine birds including three species (S. cantillans, S. subalpina and S. inornata) that are further subdivided into four subspecies (S. c. cantillans, S. c. albistriata, S. i. inornata, S. i. iberiae). All taxa in the complex are morphologically similar and difficult to discern from each other based on plumage. Furthermore, sexing birds is also difficult as females and males without breeding plumage are almost identical. In this study I used molecular methods to identify S. cantillans complex birds in order to compare field-based and molecular observations. DNA was extracted from a set of feathers collected from S. cantillans complex birds from Italy to determine species, based on mitochondrial gene cytochrome b sequences. The sex was determined using PCR amplicon profiles of CHD1W and CHD1Z genes that differ in size between males and females. The cytochrome b amplification was successful in all feathers and CHD1W and CHD1Z in all but two. The molecular work was compared with the results of phenotypic identification made by ringers and expert ornithologists. The experts on average, identified the correct species in 51% of the warblers, and sex 66% and 64% for females and males respectively. This highlights that molecular methods are highly effective to determine species and sex and that they are more reliable than identification by plumage alone. This is important to keep in mind in studies of diversity and conservation to avoid underestimating the number of species and the sex of individuals involved, which might cause more harm than good.

  • 21.
    Ahlberg, Marcus
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Ökad förekomst av torrstressade granar2021Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    I svenska granrika skogsbestånd har andelen granbarkborreangrepp ökatunder åren. Skadedrabbat virke har lett till stora ekonomiska förluster förskogsägare. Medialt sett har antropogena klimatförändringar fått ett stortutrymme som den primära boven. Detta förknippas initialt med stormenGudrun som svepte över södra Sverige år 2005 där en ovanligt stor andelgranarskog föll för vindens krafter och blev måltavla för olika skadeinsekter.På senare år är det istället de långa varma somrarna som varit på agendan.Vilka faktorer är det primärt som ligger till grund för att fler granar blirtorrstressade och drar åt sig granbarkborrar? Är det på grund av att det odlasgran i monokultur eller har det att göra med att granen kan tillgodose sig förlite vatten? I detta arbete undersöks vilka faktorer som primärt ligger tillgrund för andelen torrstressade granar. Genom en fältinsamling samtkompletterande dokument med information om skogsodlingar har det samlatsin data om andelen torrstressade granar, markegenskaper: tillgång till rörligtmarkvatten eller ej samt andelen gran i procent för varje skogsplantering.Avsaknaden av rörligt markvatten det vill säga att skogsområdet är flacktvisar sig bidra till fler torrstressade granar. Granrika bestånd visar sig ocksåbidra till att andelen torrstressade granar blir högre, vilket i sin tur utgör enstörre risk för angrepp. Precis som tidigare studier visar sig odlingar medgran som odlas i monokultur ha en sämre motståndskrafts motgranbarkborreangrepp. Resultatet pekar alltså på att man bör odla mindregran i monokultur samt tillämpa ståndortsanpassning i sluttande markpartierför att ge granens marknära rötter bättre möjlighet att tillgodose sig marknäravatten. 

    Fulltekst (pdf)
    fulltext
  • 22.
    Ahlstrom, Christina A.
    et al.
    US Geol Survey, USA.
    van Toor, Mariëlle L.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Woksepp, Hanna
    Kalmar County Hospital, Sweden.
    Chandler, Jeffrey C.
    USDA APHIS WS, USA.
    Reed, John A.
    US Geol Survey, USA.
    Reeves, Andrew B.
    US Geol Survey, USA.
    Waldenström, Jonas
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Franklin, Alan B.
    USDA APHIS WS, USA.
    Douglas, David C.
    US Geol Survey, USA.
    Bonnedahl, Jonas
    Linköping University, Sweden;Region Kalmar county, Sweden.
    Ramey, Andrew M.
    US Geol Survey, USA.
    Evidence for continental-scale dispersal of antimicrobial resistant bacteria by landfill-foraging gulls2021Inngår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 764, s. 1-10, artikkel-id 144551Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Anthropogenic inputs into the environment may serve as sources of antimicrobial resistant bacteria and alter the ecology and population dynamics of synanthropic wild animals by providing supplemental forage. In this study, we used a combination of phenotypic and genomic approaches to characterize antimicrobial resistant indicator bacteria, animal telemetry to describe host movement patterns, and a novel modeling approach to combine information from these diverse data streams to investigate the acquisition and long-distance dispersal of antimicrobial resistant bacteria by landfill-foraging gulls. Our results provide evidence that gulls acquire antimicrobial resistant bacteria from anthropogenic sources, which they may subsequently disperse across and between continents via migratory movements. Furthermore, we introduce a flexible modeling framework to estimate the relative dispersal risk of antimicrobial resistant bacteria in western North America and adjacent areas within East Asia, which may be adapted to provide information on the risk of dissemination of other organisms and pathogens maintained by wildlife through space and time. Published by Elsevier B.V.

  • 23.
    Ahsan, Murshidul
    et al.
    Bangladesh Agricultural University (BAU), Bangladesh.
    Hasan, Badrul
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Uppsala University .
    Algotsson, Magnus
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Sarenbo, Sirkku
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Handling and Welfare of Bovine Livestock at Local Abattoirs in Bangladesh2014Inngår i: Journal of Applied Animal Welfare Science, ISSN 1088-8705, E-ISSN 1532-7604, Vol. 17, nr 4, s. 340-353Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The World Organization for Animal Health (OIE) allows rope casting and the tying of legs for nonhuman animals laughter without stunning. Thehandling and welfare of bovine livestock (Bosindicus and Bubalus bubalis) were studied in 8 local abattoirs in 5 districts of Bangladesh. A totalof 302 animals were evaluated. At the local abattoirs, approximately 1/3 of the cattle and water buffalo were eithere maciated orinjured/sick. The size and vigor of the animals determined the casting method. Small and weak animals were cast on concrete floors by lifting a foreleg followed by pushing, or simply by twisting the head of the animal and then binding the legs with rope. Vigorous animals such as buffalo were castusing ropes and human force. Bleeding was slow and flaying was sometimes initiated before the animals were unconscious. Pulling and tearing of the trachea and pouring of water into the exposed trache a shortly after cutting were also observed in some cases.The over all animal handling was unnecessarily rough and he OIE standards were not implemented. Animals are subjected to considerable mistreatment, and there is an urgent need for the training nde ducation of the staff in a battoirs concerning humanes laughtering practices as well as a need to build moderns laughtering plants in Bangladesh.

  • 24.
    Akram, Neelam
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    From genes to ecological function in marine bacteria2013Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Bacteria in the sea are constantly exposed to environmental challenges (e.g. variations in nutrient concentrations, temperature and light conditions), and therefore appropriate gene expression response strategies to cope with them efficiently are evolved. This thesis investigates some interconnected questions regarding such adaptive strategies employed by marine bacteria.

    The recently discovered ability of bacteria to use the membrane protein proteorhodopsin (PR) to harvest light energy for cell metabolism were investigated in Vibrio sp. AND4 and Dokdonia sp. MED134. PR phototrophy in AND4 promoted survival during starvation, the molecular basis for which were the upregulation of the PR gene by nutrient limitation rather than light. MED134, in contrast, uses PR phototrophy to grow better, and we discovered that the light-stimulated growth was stronger in seawater with the single carbon compound alanine compared to a mixture of complex organic matter. Thus, differences between bacteria in PR gene expression regulation in response to light, nutrients or organic matter quality critically determine the ecological role of PR phototrophy in the sea.

    Current observations that membrane transporters (including PR) are highly expressed in seawater inspired a comparative analysis of transporter distributions in marine bacteria. Totally, 192 transporter families were found in 290 genome-sequenced strains. Consistent differences, but also similarities, in the number of transporters were found between major bacterial groups. Interestingly, sodium transporters were found to be more abundant in PR-containing SAR11. These findings suggest that bacteria have inherently distinctive potentials to adapt to resource variations in the sea.

    To examine links between transcriptional responses and growth of bacteria under controlled environmental settings, a mesocosm phytoplankton bloom experiment was performed. Transcriptional analysis of the microbial community (i.e. metatranscriptomics) revealed 2800 categories of functional genes (SEED functions), of which around 10% were overrepresented in either the bloom mesocosms or the controls. Importantly, these functions indicated potential metabolic mechanisms (e.g. TonB mediated nutrient transport) by which bacteria took advantage of the bloom conditions.

    This thesis combines analyses of model organisms with community analysis and highlights the possibilities to identify important mechanisms that underlie the ecological success of different bacteria in the marine environment. 

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    presentationsbild
  • 25.
    Akram, Neelam
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Palovaara, Joakim
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Forsberg, Jeremy
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Lindh, Markus V.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Milton, Debra L.
    Luo, Haiwei
    Gonzalez, Jose M.
    Pinhassi, Jarone
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Regulation of proteorhodopsin gene expression by nutrient limitation in the marine bacterium Vibrio sp AND42013Inngår i: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 15, nr 5, s. 1400-1415Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Proteorhodopsin (PR), a ubiquitous membrane photoprotein in marine environments, acts as a light-driven proton pump and can provide energy for bacterial cellular metabolism. However, knowledge of factors that regulate PR gene expression in different bacteria remains strongly limited. Here, experiments with Vibrio sp. AND4 showed that PR phototrophy promoted survival only in cells from stationary phase and not in actively growing cells. PR gene expression was tightly regulated, with very low values in exponential phase, a pronounced peak at the exponential/stationary phase intersection, and a marked decline in stationary phase. Thus, PR gene expression at the entry into stationary phase preceded, and could therefore largely explain, the stationary phase light-induced survival response in AND4. Further experiments revealed nutrient limitation, not light exposure, regulated this differential PR expression. Screening of available marine vibrios showed that the PR gene, and thus the potential for PR phototrophy, is found in at least three different clusters in the genus Vibrio. In an ecological context, our findings suggest that some PR-containing bacteria adapted to the exploitation of nutrient-rich micro-environments rely on a phase of relatively slowly declining resources to mount a cellular response preparing them for adverse conditions dispersed in the water column.

  • 26.
    Alakangas, Linda J.
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). SKB, Äspo Hard Rock Lab, Oskarshamn.
    Mathurin, Frédéric A.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Faarinen, Mikko
    ALS Scandinavia AB Luleå.
    Wallin, Bill
    Geokema AB, Lidingö.
    Åström, Mats E.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Sampling and Characterizing Rare Earth Elements in Groundwater in Deep-Lying Fractures in Granitoids Under In Situ High-Pressure and Low-Redox Conditions2014Inngår i: Aquatic geochemistry, ISSN 1380-6165, E-ISSN 1573-1421, Vol. 20, nr 4, s. 405-418Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Several countries are preparing to dispose of radioactive nuclear waste deep underground in crystalline rock. This type of bedrock is commonly extensively fractured and consequently carries groundwater that serves as a medium for transporting metals and radionuclides. A group of metals of particular interest in this context is the rare earth elements (REEs), because they are analogues of actinides contained within radioactive waste and are tracers of hydrological pathways and geochemical processes. Concentrations of REEs are commonly low in these groundwaters, leading to values below detection limits of standard monitoring methods, particularly for the heavy REEs. We present a new technical set-up for monitoring REEs (and other trace metals) in groundwater in fractured crystalline rock. The technique consists of passing the fracture groundwater, commonly under high pressure and containing reduced chemical species, through a device that maintains the physicochemical character of the groundwater. Within the device, diffusive gradient in thin-film (DGT) discs are installed in triplicate. With this set-up, we studied REEs in groundwater in fractures at depths of approximately -144, -280, and -450 m in granitoids in the A"spo Hard Rock Laboratory in southern Sweden. The entire REE suite was detected (concentrations down to 0.1 ng L-1) and was differently fractionated among the groundwaters. The shallowest groundwater, composed of dilute modern Baltic Sea water, was enriched in the heavy REEs, whereas the deeper groundwaters, dominated by old saline water, were depleted in the heavy REEs. Deployment periods varying from 1 to 4 weeks delivered similar REE concentrations, indicating stability and reproducibility of the experimental set-up. The study finds that 1 week of deployment may be enough. However, if the overall setting and construction allow for longer deployment times, 2-3 weeks will be optimal in terms of reaching reliable REE concentrations well above the detection limit while maintaining the performance of the DGT samplers.

  • 27.
    Alakangas, Linda J.
    et al.
    Swedish Nucl Fuel & Waste Management Co, Sweden.
    Mathurin, Frédéric A.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Bur Rech Geol & Minieres, France.
    Åström, Mats E.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Linnéuniversitetet, Kunskapsmiljöer Linné, Vatten.
    Diverse fractionation patterns of Rare Earth Elements in deep fracture groundwater in the Baltic Shield - Progress from utilisation of Diffusive Gradients in Thin-films (DGT) at the Aspo Hard Rock Laboratory2020Inngår i: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 269, s. 15-38Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Rare earth elements (REEs) were studied in groundwater in fractures at depths between 144 m and 450 m in Proterozoic granitoids on the Baltic Shield at a coastal site in south eastern Sweden (Aspo Hard Rock Laboratory). A specially designed device was used to sample the groundwater under in situ high pressure and low redox conditions. The REEs were measured via both diffusive gradients in thin-films (DGT) samplers after approximately three-week deployment times, and after conventional filtration (0.45 mu m membrane filters). The concentrations of REEDGT were lower than the REE0.45 mu m concentrations in all 14 studied groundwaters. This is explained by development of a diffuse boundary layer (DBL) in the solution at the DGTs caused by the low flow, and in some of the groundwaters additionally by the presence of organically complexed REE that diffuse slowly in the diffusive gel of the DGT. Among the 14 studied groundwaters there was a huge range in REEDGT-fractionation patterns, ranging from enrichment to a nearly three-order-of-magnitude depletion of the heavy REEs (HREEs), despite a relatively homogenous bedrock (granitoids). The HREE enrichment is explained by preservation of the fractionation signature as HREE enriched sea water intruded and flowed through the fractures, supported by the high proportion of modelled REE fulvic-acid complexes in these waters. The strong HREE depletion, which occurred in saline groundwater, was ascribed to an advanced REE equilibrium between the groundwater and primary and/or secondary minerals and the pore water in the bedrock. Yet other groundwaters had flat or moderately HREE depleted patterns, which in some cases may have been caused by mixing of small portions of surficial waters with saline groundwater. (C) 2019 Elsevier Ltd. All rights reserved.

  • 28.
    Alam, A. B. M. Sarowar
    et al.
    IUCN Bangladesh, Dhaka, Bangladesh..
    Ahmed, Sakib
    IUCN Bangladesh, Bangladesh.
    Azmiri, Kazi Zenifar
    IUCN Bangladesh, Bangladesh.
    Amin, Raquibul
    IUCN Bangladesh, Bangladesh.
    van Toor, Mariëlle L.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Datta, Ashis Kumar
    Jahangirnagar Univ, Bangladesh.
    Waldenström, Jonas
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Ul Haque, Enam
    Bangladesh Bird Club, Bangladesh.
    Chowdhury, Sayam U.
    Univ Cambridge, UK.
    Population trends and effects of local environmental factors on waterbirds at Tanguar Haor freshwater wetland complex in northeast Bangladesh2023Inngår i: Avian Conservation and Ecology, E-ISSN 1712-6568, Vol. 18, nr 1, artikkel-id 18Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Analysis of long-term datasets on bird populations can be used to answer ecological and management questions that are useful for conservation. Tanguar Haor (9500 ha) is one of the major freshwater wetlands in Bangladesh and supports a large number of migratory and resident waterbirds. Because of its unique ecological and economic values, it is arguably the most notable wetland in the floodplains of northeast Bangladesh and in the region. This Ramsar site supports globally important populations of threatened waterbirds, such as the Baer's Pochard Aythya baeri, Common Pochard Aythya ferina, Falcated Duck Mareca falcata, Ferruginous Duck Aythya nyroca, Oriental Darter Anhinga melanogaster, and Black-tailed Godwit Limosa limosa. Considering the international significance of this site, knowledge gaps on waterbird population trends, and key ecological factors, we conducted waterbird census between 2008 and 2021 to identify priority sites for conservation, population trends of resident and migratory waterbirds, and environmental factors that influence their abundances. We recorded a total of 69 species of waterbirds (maximum count of 166,788 individuals in 2013) and assessed population trends of 47 species. Of these, peak counts of 15 species exceeded the 1% threshold of their Asian-Australian Flyway population estimates. Most species (59%) showed a declining trend, including the critically endangered Baer's Pochard and the vulnerable Common Pochard, and 16 species (41%) showed an increasing trend. Based on the abundance and species diversity, we have identified Chotainna beel and Lechuamara beel as conservation priority sites within the Haor complex and discuss key threats to these areas. We also offer evidence that adjusting water-level management to annual rainfall patterns could be a useful intervention for waterbird management. Involving local communities in conservation efforts by creating bird sanctuaries within the Haor complex will strengthen waterbird conservation in the country and along the East Asian-Australian Flyway.

  • 29.
    Ale Ebrahim Dehkordi, Molood
    et al.
    Delft University of Technology, Netherlands.
    Ghorbani, Amineh
    Delft University of Technology, Netherlands.
    Bravo, Giangiacomo
    Linnéuniversitetet, Fakulteten för samhällsvetenskap (FSV), Institutionen för samhällsstudier (SS). Linnéuniversitetet, Kunskapsmiljöer Linné, Vatten.
    Farjam, Mike
    Lund University, Sweden.
    van Weeren, René
    Utrecht University, Netherlands.
    Forsman, Anders
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    De Moor, Tine
    Erasmus University, Netherlands.
    Long-term dynamics of institutions: Using ABM as a complementary tool to support theory development in historical studies2021Inngår i: JASSS: Journal of Artificial Societies and Social Simulation, E-ISSN 1460-7425, Vol. 24, nr 4, artikkel-id 7Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Historical data are valuable resources for providing insights into social patterns in the past. However, these data often inform us at the macro-level of analysis but not about the role of individuals’ behaviours in the emergence of long-term patterns. Therefore, it is difficult to infer ‘how’ and ‘why’ certain patterns emerged in the past. Historians use various methods to draw hypotheses about the underlying reasons for emerging patterns and trends, but since the patterns are the results of hundreds if not thousands of years of human behaviour, these hypotheses can never be tested in reality. Our proposition is that simulation models and specifically, agent-based models (ABMs) can be used as complementary tools in historical studies to support hypothesis building. The approach that we propose and test in this paper is to design and configure models in such a way as to generate historical patterns, consequently aiming to find individual-level explanations for the emerging pattern. In this work, we use an existing, empirically validated, agent-based model of common pool resource management to test hypotheses formulated based on a historical dataset. We first investigate whether the model can replicate various patterns observed in the dataset, and second, whether it can contribute to a better understanding of the underlying mechanism that led to the observed empirical trends. We showcase how ABM can be used as a complementary tool to support theory development in historical studies. Finally, we provide some guidelines for using ABM as a tool to test historical hypotheses.

  • 30.
    Alegria Zufia, Javier
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Farnelid, Hanna
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Linnéuniversitetet, Kunskapsmiljöer Linné, Vatten.
    Legrand, Catherine
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Linnéuniversitetet, Kunskapsmiljöer Linné, Vatten. Halmstad University, Sweden.
    Seasonality of Coastal Picophytoplankton Growth, Nutrient Limitation, and Biomass Contribution2021Inngår i: Frontiers in Microbiology, E-ISSN 1664-302X, Vol. 12, artikkel-id 786590Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Picophytoplankton in the Baltic Sea includes the simplest unicellular cyanoprokaryotes (Synechococcus/Cyanobium) and photosynthetic picoeukaryotes (PPE). Picophytoplankton are thought to be a key component of the phytoplankton community, but their seasonal dynamics and relationships with nutrients and temperature are largely unknown. We monitored pico- and larger phytoplankton at a coastal site in Kalmar Sound (K-Station) weekly during 2018. Among the cyanoprokaryotes, phycoerythrin-rich picocyanobacteria (PE-rich) dominated in spring and summer while phycocyanin-rich picocyanobacteria (PC-rich) dominated during autumn. PE-rich and PC-rich abundances peaked during summer (1.1 x 10(5) and 2.0 x 10(5) cells mL(-1)) while PPE reached highest abundances in spring (1.1 x 10(5) cells mL(-1)). PPE was the main contributor to the total phytoplankton biomass (up to 73%). To assess nutrient limitation, bioassays with combinations of nitrogen (NO3 or NH4) and phosphorus additions were performed. PE-rich and PC-rich growth was mainly limited by nitrogen, with a preference for NH4 at >15 degrees C. The three groups had distinct seasonal dynamics and different temperature ranges: 10 degrees C and 17-19 degrees C for PE-rich, 13-16 degrees C for PC-rich and 11-15 degrees C for PPE. We conclude that picophytoplankton contribute significantly to the carbon cycle in the coastal Baltic Sea and underscore the importance of investigating populations to assess the consequences of the combination of high temperature and NH4 in a future climate.

  • 31.
    Alegria Zufia, Javier
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Legrand, Catherine
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Linnéuniversitetet, Kunskapsmiljöer Linné, Vatten. Halmstad University, Sweden.
    Farnelid, Hanna
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Linnéuniversitetet, Kunskapsmiljöer Linné, Vatten.
    Seasonal dynamics in picocyanobacterial abundance and clade composition at coastal and offshore stations in the Baltic Sea2022Inngår i: Scientific Reports, E-ISSN 2045-2322, Vol. 12, nr 1, artikkel-id 14330Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Picocyanobacteria (< 2 mu m in diameter) are significant contributors to total phytoplankton biomass. Due to the high diversity within this group, their seasonal dynamics and relationship with environmental parameters, especially in brackish waters, are largely unknown. In this study, the abundance and community composition of phycoerythrin rich picocyanobacteria (PE-SYN) and phycocyanin rich picocyanobacteria (PC-SYN) were monitored at a coastal (K-station) and at an offshore station (LMO; similar to 10 km from land) in the Baltic Sea over three years (2018-2020). Cell abundances of picocyanobacteria correlated positively to temperature and negatively to nitrate (NO3) concentration. While PE-SYN abundance correlated to the presence of nitrogen fixers, PC-SYN abundance was linked to stratification/shallow waters. The picocyanobacterial targeted amplicon sequencing revealed an unprecedented diversity of 2169 picocyanobacterial amplicons sequence variants (ASVs). A unique assemblage of distinct picocyanobacterial clades across seasons was identified. Clade A/B dominated the picocyanobacterial community, except during summer when low NO3, high phosphate (PO4) concentrations and warm temperatures promoted S5.2 dominance. This study, providing multiyear data, links picocyanobacterial populations to environmental parameters. The difference in the response of the two functional groups and clades underscore the need for further high-resolution studies to understand their role in the ecosystem.

    Fulltekst (pdf)
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  • 32.
    Alegria Zufía, Javier
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Picophytoplankton seasonal dynamics in the Baltic Sea2022Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Picophytoplankton (<2 μm diameter) is a diverse group of picocyanobacterial and photosynthetic picoeukaryotes (PPE).Picophytoplankton contribute significantly to total phytoplankton biomassand can dominate primary production in oceans, lakes and estuaries. In the estuarine Baltic Sea, the composition of picophytoplankton is linked to the north to south salinity gradient but knowledge of the seasonal dynamics interms of abundance, biomass and diversity is largely unknown. This thesis investigated the in situ dynamics, bottom up and top down controls of picocyanobacteria (SYN; consisting of primarily Synechococcus and Cyanobium among other genuses) and PPE at two sampling stations, one coastal and one offshore. Monitoring data over three years (2018-2020) showed high biomass contribution across all seasons. Picocyanobacterial peak abundances occurred from spring to summer at the coastal station and in late-summer to autumn at the offshore station (up to 4.7 × 105 cells mL-1).Differentiation of pigment populations showed that phycoerythrin rich(PE)-SYN was the main contributor to SYN abundances except at the coastalstation during summer, when PE-SYN and phycocyanin rich (PC)-SYN had equal contributions. PPE peak abundances occurred during late summer to autumn (up to 1.1 × 105 cells mL-1 cells ml-1). Temperature was linked topicophytoplankton growth and abundance, with PE-SYN, PCSYN and PPEadapted to different temperature ranges. Temperature also affected SYNnitrogen preference: SYN was nitrogen limited during early summer and at>15°C there was a preference for ammonium over nitrate. Clade A/B dominated the SYN community, except during summer at the coastal station when low nitrate and warm temperatures promoted S5.2 dominance. Grazing was observed to control SYN and PPE abundances and had an effect on the SYN community structure. Identification and laboratory experiments of key Synechococcus strains using a range of salinity, temperature and light conditions provided important insights into the physiological diversity of co-occurring ecotypes and links to the SYN dynamics that were observed in the field. In summary, this thesis provided novel information of picophytoplankton dynamics and community structure in the Baltic Sea. The results show that picophytoplankton play a relevant role in Baltic Sea and shows the importance of monitoring programs to understand picophytoplankton dynamics.

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  • 33.
    Ali, Muatasem Latif
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Riskkommunikation generellt exemplifierat genom branden i Halmstad 20122017Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    A chemical accident can cause damage in individuals, groups or entire communities. The injury may concern human life, property or the environment. An accident can affect a large part of society and requires cooperation between the actors involved. Different stakeholders need to be informed, but it is not certain how a message should be delivered and who should do it.

    The study's purpose is to study risk communication generally, as exemplified by the accident in Halmstad September 21, 2012, when a fire broke out in a warehouse in Halmstad harbor. How the involved persons experienced communication,

    What factors could affect the communication at such types of critical situations.

    In the study, two methods have been used. The first used method was a web-survey of people working in civil protection in Halmstad municipality, environmental office in Halmstad, the public living in the municipality, police, Coast Guard, industries and media. The second method was semi-structured interviews addressed to some of those affected who worked in media, police, coast guard, the company, emergency services and the local authority.

    This study showed that there were differences between the respondents' answers on how respondents perceived that there were risks to human health or the environment in this accident. Many of the respondents who responded to the survey felt that the risk communication worked well after the fire. This survey and semi- structured interviews showed that respondents felt that the municipality's website was a good information channel and the internet and social media could be a good source for the responsible authorities to quickly disseminate information to the public. This study showed that the municipality and emergency services were actors most concerned in this context when it came to communicating risks in major accidents where chemicals were involved and all respondents had great confidence to the emergency services and municipality. 

    Fulltekst (pdf)
    fulltext
  • 34.
    Almqvist, Maria
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Vanvårdens inverkan på nötkreaturs välfärd och hälsa2013Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Farmers are required to make sure that cattles basic needs are met, but still every year cases of neglect occur where the farmer has not complied within the animal welfare law and regulations. The aim of this study was to investigate how cattle are affected physically and behaviourally by neglect in the form of underfeeding, starvation and lack of sanitation, which animals are most vulnerable to the impact and what prospects they have to recover. The study was conducted as a literature study and the results show that these types of neglect have a large impact on the cattle welfare. Underfeeding and starvation causes physical changes leading to reduced milk production, reduced muscle mass, impaired immune function, poor reproductive performance and changes in rumen microflora leading to decreased number of microbes and pH change. Physical changes due to the lack of sanitation consist of increased vulnerability to hoof diseases and mastitis, burns, and increased sensitivity to temperature. The behaviourally changes that occur because of underfeeding and starvation include changes in eating habits, reduced lying time and reduced sleeping time. Insufficient sanitation cause behavioural changes including changes in laying time, increased agression, and slower movement. Pregnant cows and cows at peak lactation are sensitive to underfeeding and starvation, but also calves. Cattle kept in groups are most at risk for being contaminated. If the neglect is not too severe or prolonged, recovery can take place but in more serious cases of neglect, there is danger of the cattle’s life.

    Fulltekst (pdf)
    fulltext
  • 35.
    Alneberg, Johannes
    et al.
    KTH Royal instute of technology, Sweden.
    Bennke, Christin
    Leibniz Inst Balt Sea Res, Germany.
    Beier, Sara
    Leibniz Inst Balt Sea Res, Germany;Sorbonne Univ, France.
    Bunse, Carina
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Carl von Ossietzky Univ Oldenburg, Germany;Alfred Wegener Institut, Germany.
    Quince, Christopher
    Univ Warwick, UK.
    Ininbergs, Karolina
    Stockholm University, Sweden;Karolinska Institutet, Sweden.
    Riemann, Lasse
    Univ Copenhagen, Denmark.
    Ekman, Martin
    Stockholm University, Sweden.
    Juergens, Klaus
    Leibniz Inst Balt Sea Res, Germany.
    Labrenz, Matthias
    Leibniz Inst Balt Sea Res, Germany.
    Pinhassi, Jarone
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Linnéuniversitetet, Kunskapsmiljöer Linné, Vatten.
    Andersson, Anders F.
    KTH Royal instute of technology, Sweden.
    Ecosystem-wide metagenomic binning enables prediction of ecological niches from genomes2020Inngår i: Communications Biology, E-ISSN 2399-3642, Vol. 3, nr 1, s. 1-10, artikkel-id 119Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Alneberg et al. conduct metagenomics binning of water samples collected over major environmental gradients in the Baltic Sea. They use machine-learning to predict the placement of genome clusters along niche gradients based on the content of functional genes. The genome encodes the metabolic and functional capabilities of an organism and should be a major determinant of its ecological niche. Yet, it is unknown if the niche can be predicted directly from the genome. Here, we conduct metagenomic binning on 123 water samples spanning major environmental gradients of the Baltic Sea. The resulting 1961 metagenome-assembled genomes represent 352 species-level clusters that correspond to 1/3 of the metagenome sequences of the prokaryotic size-fraction. By using machine-learning, the placement of a genome cluster along various niche gradients (salinity level, depth, size-fraction) could be predicted based solely on its functional genes. The same approach predicted the genomes' placement in a virtual niche-space that captures the highest variation in distribution patterns. The predictions generally outperformed those inferred from phylogenetic information. Our study demonstrates a strong link between genome and ecological niche and provides a conceptual framework for predictive ecology based on genomic data.

  • 36.
    Alneberg, Johannes
    et al.
    KTH Royal Institute of Technology, Sweden.
    Karlsson, Christofer M. G.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Divne, Anna-Maria
    Uppsala University, Sweden.
    Bergin, Claudia
    Uppsala University, Sweden.
    Homa, Felix
    Uppsala University, Sweden.
    Lindh, Markus V.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Lund University, Sweden.
    Hugerth, Luisa W.
    KTH Royal Institute of Technology, Sweden;Karolinska Institutet, Sweden.
    Ettema, Thijs J. G.
    Uppsala University, Sweden.
    Bertilsson, Stefan
    Uppsala University, Sweden.
    Andersson, Anders F.
    KTH Royal Institute of Technology, Sweden.
    Pinhassi, Jarone
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Genomes from uncultivated prokaryotes: a comparison of metagenome-assembled and single-amplified genomes2018Inngår i: Microbiome, E-ISSN 2049-2618, Vol. 6, artikkel-id 173Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Prokaryotes dominate the biosphere and regulate biogeochemical processes essential to all life. Yet, our knowledge about their biology is for the most part limited to the minority that has been successfully cultured. Molecular techniques now allow for obtaining genome sequences of uncultivated prokaryotic taxa, facilitating in-depth analyses that may ultimately improve our understanding of these key organisms. Results: We compared results from two culture-independent strategies for recovering bacterial genomes: single-amplified genomes and metagenome-assembled genomes. Single-amplified genomes were obtained from samples collected at an offshore station in the Baltic Sea Proper and compared to previously obtained metagenome-assembled genomes from a time series at the same station. Among 16 single-amplified genomes analyzed, seven were found to match metagenome-assembled genomes, affiliated with a diverse set of taxa. Notably, genome pairs between the two approaches were nearly identical (average 99.51% sequence identity; range 98.77-99.84%) across overlapping regions (30-80% of each genome). Within matching pairs, the single-amplified genomes were consistently smaller and less complete, whereas the genetic functional profiles were maintained. For the metagenome-assembled genomes, only on average 3.6% of the bases were estimated to be missing from the genomes due to wrongly binned contigs. Conclusions: The strong agreement between the single-amplified and metagenome-assembled genomes emphasizes that both methods generate accurate genome information from uncultivated bacteria. Importantly, this implies that the research questions and the available resources are allowed to determine the selection of genomics approach for microbiome studies.

  • 37.
    Alneberg, Johannes
    et al.
    KTH Royal Institute of Technology, Sweden.
    Sundh, John
    Stockholm University, Sweden.
    Bennke, Christin
    Leibniz Inst Balt Sea Res Warnemunde, Germany.
    Beier, Sara
    Leibniz Inst Balt Sea Res Warnemunde, Germany.
    Lundin, Daniel
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Hugerth, Luisa W.
    KTH Royal Institute of Technology, Sweden.
    Pinhassi, Jarone
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Kisand, Veljo
    Univ Tartu, Estonia.
    Riemann, Lasse
    Univ Copenhagen, Denmark.
    Juergens, Klaus
    Leibniz Inst Balt Sea Res Warnemunde, Germany.
    Labrenz, Matthias
    Leibniz Inst Balt Sea Res Warnemunde, Germany.
    Andersson, Anders F.
    KTH Royal Institute of Technology, Sweden.
    BARM and BalticMicrobeDB, a reference metagenome and interface to meta-omic data for the Baltic Sea2018Inngår i: Scientific Data, E-ISSN 2052-4463, Vol. 5, artikkel-id 180146Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Baltic Sea is one of the world's largest brackish water bodies and is characterised by pronounced physicochemical gradients where microbes are the main biogeochemical catalysts. Meta-omic methods provide rich information on the composition of, and activities within, microbial ecosystems, but are computationally heavy to perform. We here present the Baltic Sea Reference Metagenome (BARM), complete with annotated genes to facilitate further studies with much less computational effort. The assembly is constructed using 2.6 billion metagenomic reads from 81 water samples, spanning both spatial and temporal dimensions, and contains 6.8 million genes that have been annotated for function and taxonomy. The assembly is useful as a reference, facilitating taxonomic and functional annotation of additional samples by simply mapping their reads against the assembly. This capability is demonstrated by the successful mapping and annotation of 24 external samples. In addition, we present a public web interface, BalticMicrobeDB, for interactive exploratory analysis of the dataset. [GRAPHICS] .

  • 38.
    Alriksson, Claes-Göran
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Texturvariationer i skogsmark - effekter på tillväxt och gödslingsrespons?: Studie i ett försök med behovsanpassad gödsling i Ebbegärde2019Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [sv]

    En mängd olika ståndortsfaktorer påverkar trädens tillväxt. Några av dessa kan påverkas genom olika skogsskötselmetoder, t ex näringstillförsel. I ett flertal försök de senaste decennierna har skogsgödsling visat sig kunna öka tillväxten markant. Faktorer som inte är påverkbara, som t ex markens textur och markens jorddjup kan då bli begränsande för tillväxten eftersom en finkornig textur oftast är gynnsam ur tillväxtsynpunkt. Föreliggande undersökning syftar till att se om det finns en texturvariation inom en begränsad yta och dess effekter på tillväxten. Texturen undersöktes genom torrsiktning. Resultaten visar att det förelåg en stor variation av texturen på beståndsnivå och att det kan påverka tillväxten i kombination med andra begränsande faktorer såsom vattentillgång.

    Fulltekst (pdf)
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  • 39.
    Alriksson, Stina
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Attitudes towards the transition from traditional product design to ecodesign2015Inngår i: Risk, Uncertainty and Transition, 2015Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Many efforts have been made to increase the use of ecodesign in product design projects. Still, ecodesign methods are not applied as often as wanted from sustainability perspectives. New methods and procedures are often considered a risk by the individuals that are meant to use and implement the new methods.  Organisational complexity, lack of cooperation, lack of tools, lack of internal communication and lack of management commitment are documented barriers to the use of ecodesign and explain some of the reasons why ecodesign is not used as widely as expected. The perception of the employees and the behavioural barriers they perceive are less studied and there is a need to correlate the perception of the individual to the identified barriers.

    This study aimed to identify what factors that inhibited the ecodesign behaviour of the employees by applying the theory of planned behaviour.  Nine persons involved in the design process from two companies were included in the study. Q-methodology combined with semi-structured interviews was applied. The statements in the Q-sort were constructed from the theory of planned behaviour so that intention, personal norm, attitude, habits, subjective norm and perceived control each had a set of statements.

    The results showed that the participants were positive in their attitude towards ecodesign. They also had strong personal norms and showed intention to use ecodesign in their work. On the lower side, former habits were not a strong driving force; neither was subjective norm or perceived control. The results indicate that the employees were positive and intended to use ecodesign while they did not find the management commitment and current ecodesign tools and procedures sufficient.

    Four discourses were identified; those who were positive towards ecodesign but not inclined to change their current behaviour, those who felt pressure from others to perform ecodesign, those who wanted to take small steps by starting to change internal procedures before talking to the customer and finally those who did not believe there was any chance of success with ecodesign.

  • 40.
    Alriksson, Stina
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Environmental preferences among steel stakeholders2013Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Emissions of carbon dioxide, dioxins, nitrogen oxides and particulate matter as well as use of non-renewable resources and energy are some important sustainability challenges for the Swedish steel industry. Much effort has been made, mainly by technical solutions, which to a high degree have decreased the emissions during the last 30 years.

    Technical solutions however will not be sufficient to reach sustainable development, stakeholder involvement is also necessary. Stakeholder theory states that stake­holder involvement must include a dialog between the stakeholders involved and the operation. The first step in this process is to identify which key issues the stakeholders find most important and then the organisation needs to start interact with its stakeholders. This thesis deals with such issues.

    Stakeholder preferences for environmental issues were assessed with conjoint analysis, Q-methodology and focus group discussions. The theory of planned behaviour was used to assess how attitudes were connected to background factors and a potential pro-environmental behaviour.

    Five studies have been carried out in the framework of this thesis. The studies include: a literature review, method evaluation, evaluation of environ­mental objectives in stakeholder groups, screening of relevant factors, evaluation of steel environmental characteristics, identification of barriers to the introduction of new materials and the im­pact of worry and risk perception on strategic environmental decisions.

    It can be concluded that the methods applied in the studies work well in eliciting preferences. It has been possible to show how different stakeholder groups as well as individuals prioritise environmental objectives and sustaina­bility issues. Since individuals within a stakeholder group vary considerably in preferences, the results from this thesis show the importance of illustrating results on an individual level instead of the traditional group level. Also, a method has been tested where the results were brought back to the respondents in order to stimulate discussions between different stakeholder groups.

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  • 41.
    Alriksson, Stina
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Methods to measure stakeholder preferences2015Konferansepaper (Annet vitenskapelig)
  • 42.
    Alriksson, Stina
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Filipsson, Monika
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Risk perception and worry in environmental decision-making - a case study within the Swedish steel industry2017Inngår i: Journal of Risk Research, ISSN 1366-9877, E-ISSN 1466-4461, Vol. 20, nr 9, s. 1173-1194Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Sustainable development is an important issue for the industry in order to fulfil legislation requirements and to be able to use green marketing as a competitive advantage. The Swedish steel industry has implemented a large number of environmental improvements, for example, within energy efficiency, raw materials and recyclability. Technical improvements can help the industry decrease its environmental impact; however, in order to reach sustainable development, more factors need to be considered: an effective environmental decision-making process, for example. This process may be influenced by personal factors such as risk perception and worry, which are factors that will not contribute to an effective decision-making process. The aim of this study was to investigate if personal worry and risk perception influenced environmental decision-making within the Swedish steel industry. Thirty-eight interviews were performed at 10 Swedish steelworks using the Q-methodology. The major perceived environmental risks with the facility and personal worry were assessed, compared to the day-to-day work. It was concluded that the major perceived risks were emissions of carbon dioxide, use of non-renewable energy and emissions of particulate matter. The decision-makers were mainly worried about emissions of carbon dioxide, emissions of dioxin and use of non-renewable energy. The environmental issues that were prioritised in practice (day-to-day work) were emissions of carbon dioxide, emissions of particulate matter and emissions of metals. Even though emissions of carbon dioxide were given the highest priority in the Q-sorts, there was in general no clear relationship between risk perception and personal worry with the prioritised environmental issues at the steelworks. The quantitative analysis of the Q-sorts and the qualitative interviews both showed that the day-to-day work was unaffected by personal worry and risk.

  • 43.
    Alriksson, Stina
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Grip, Carl-Erik
    Luleå Tekniska Universitet.
    Steel industry environmental objectives:stakeholder preference assessment usingconjoint analysis2013Inngår i: Ironmaking & steelmaking, ISSN 0301-9233, E-ISSN 1743-2812, Vol. 40, nr 8, s. 605-612Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Swedish steel industry has combined traditional methods such as life cycle analysis with less traditional methods such as preference analysis in order to move towards a closed steel eco cycle. The paper describes the use of conjoint analysis to study preferences of six different stakeholder groups regarding four environmental objectives (reduction in carbon dioxide emissions, reduced use of non-renewable resources, reduced use of non-renewable energy and weight reduction in products) and to identify gaps in preferences between the stakeholder groups. Our results suggested that there was a difference in preference between the stakeholder groups: respondents that were closer to the steel industry favoured all four environmental objectives, while members of public and political decision makers preferred a reduction in carbon dioxide emissions. One of the conclusions of our study is that there is a need of improved information to clients and public on the environmental benefits of product weight reduction.

  • 44.
    Alriksson, Stina
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Henningsson, Marianne
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för psykologi (PSY).
    Why Aren't Advanced High–Strength Steels More Widely Used?: Stakeholder Preferences and Perceived Barriers to New Materials2015Inngår i: Journal of Industrial Ecology, ISSN 1088-1980, E-ISSN 1530-9290, Vol. 19, nr 4, s. 645-655Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Advanced high-strength steels may reduce the use of nonrenewable resources and energy given that the amount of material needed is smaller, compared to traditional steel grades. Still, advanced steel grades are not utilized to the extent that could be expected. This study examines stakeholders’ preferences of steel characteristics and perceived barriers to the introduction of new materials. Focus group interviews were used to identify steel characteristics and perceived barriers. Stakeholder preferences of steel characteristics were evaluated through a conjoint analysis; the results showed that low weight was given the highest priority, followed by high impact strength and low price. Low chromium content was the steel characteristic of least interest. Perceived barriers to the introduction of high-strength steel were categorized as technical barriers, knowledge barriers, scrap management barriers, suitability barriers, and cost barriers.

  • 45.
    Alriksson, Stina
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Sahlin, Ullrika
    Lunds Universitet.
    Illustrating individual preferences from conjiont analysis studies with multivariate methodsManuskript (preprint) (Annet vitenskapelig)
  • 46.
    Alriksson, Stina
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Voxberg, Elin
    Filipsson, Monika
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Augustsson, Anna
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Historical exposure to heavy metals in air2017Inngår i: 26th SRA-E annual conference (SRA-E Lisbon 2017): Lisbon, Portugal, June 19-21, 2017, 2017Konferansepaper (Fagfellevurdert)
  • 47.
    Alriksson, Stina
    et al.
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Voxberg, Elin
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Karlsson, Helen
    Linköping University, Sweden.
    Ljunggren, Stefan
    Linköping University, Sweden.
    Augustsson, Anna
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM). Linnéuniversitetet, Kunskapsmiljöer Linné, Hållbar hälsa.
    Temporal risk assessment – 20th century Pb emissions to air and exposure via inhalation in the Swedish glass district2023Inngår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 858, nr 1, artikkel-id 159843Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The objective of the present study was to assess historical emissions of Pb to air around a number of glassworks sites in southeastern Sweden, and the possible implications for human exposure. To do so, a four-step method was applied. First, emissions of Pb to air around 10 glassworks were modelled for the 20th century. Second, an assessment of the resulting exposure was made for a number of scenarios. Third, the number of people potentially exposed at different times was estimated, and fourth, measurements of “current” Pb concentrations in PM10 material from four sites were conducted in 2019. The results show that the highest emissions, and exposures, occurred from 1970 to1980. It coincides with the time period when the highest number of people resided in the villages. At this time, the average Pb concentration in air around the six largest factories was about 2.4 μg Pb/m3, i.e. 16 times the present US national ambient air quality standard (NAAQS) of 0.15 μg Pb/m3. By year 2000 the modelled average concentration had dropped to 0.05 μg Pb/m3, a level that is normal for urban regions today. The PM10 measurements from 2019 indicate a further decline, now with a mean value of about 0.02 μg Pb/m3. Over the entire study period, inhalation hazard quotients (HQs) exceeded the dietary HQ by many orders of magnitude, indicating that inhalation has been the most prevalent exposure pathway in the past. At present, both pathways are judged to be associated with low exposures. Even if only roughly approximated, a picture of the historical exposure can increase our understanding of the connection between exposure and disease, and can be valuable when risks are to be communicated to residents near contaminated areas.

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  • 48.
    Alvunger, David
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Variation in number of vertebrae in populations of pike (Esox lucius) in the south-east of Sweden2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Antalet ryggkotor varierar kraftigt mellan olika taxa, men också inom arter eller populationer. Omfattande forskning har visat att antalet ryggkotor hos fisk är resultatet av interaktioner mellan genetisk struktur och plastiska svar på miljöbetingelser under individens ontogeni. Ett vanligt mönster är tendensen för antalet ryggkotor att variera med kroppsform och/eller kroppslängd hos fisken. Gäddan (Esox lucius) i Östersjön har en komplex populationsstruktur, bestående av flera genetiskt distinkta subpopulationer, vilka utgörs av anadroma individer som uppvisar ett homing-beteende. Individer som tillhör dessa subpopulationer är sympatriska större delen av året och blir allopatriska endast kortvarigt under tiden för lek. Den här studien undersökte fördelningen av antalet ryggkotor hos tre anadroma sympatriska subpopulationer av gädda iÖstersjön. Signifikanta skillnader i fördelningen av antalet ryggkotor hittades både inom och mellan alla undersökta subpopulationer och åldersklasser. Resultaten från ett ”common-garden” experiment antydde att skillnader i antalet ryggkotor mellan olika subpopulationer delvis hade en genetisk basis, vilket indikerar möjligheten för selektion att verka på denna egenskap, och en potentiellt evolutionär förändring. En kvadratisk regression visade på ett kurvilinjärt samband mellan antalet ryggkotor och kroppslängd hos juveniler. Tillsammans tyfrt dessa resultat på att de kombinerade effekterna av stabiliserande och divergent selektion kan ha spelat en roll i fördelningen av antalet ryggkotor hos gäddan i Östersjön. Fördelningen av antalet ryggkotor inom subpopulationer verkar vara under inflytande av stabiliserande selektion. Skillnader mellan subpopulationer kan istället reflektera lokala anpassningar som drivs av divergent selektion. Dessa fynd signalerar behovet av att betrakta varje subpopulation som en egen enhet i bevarandebiologiska sammanhang.

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  • 49.
    Alwan, Heba
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Understanding the potential future capacity of distributing green steel solutions - current knowledge and future challenges2023Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Transitioning from the conventional steel process to a direct hydrogen reduction process in the steel industry is a significant step towards reducing carbon dioxide emissions and achieving greater sustainability. The process involves using hydrogen gas as a reducing agent instead of carbon to remove oxygen from the iron ore. This study aimed to investigate the future capacity of the hydrogen-based steelmaking process in Sweden by 2050 while also examining the pathway for transitioning to hydrogen-based steelmaking in other European countries in comparison to the Swedish case. To achieve this goal, a systematic literature search was conducted using Scopus and Web of Science databases to identify relevant case studies and reviews that focused on green steel solutions and that discussed associated challenges and barriers. A aconsupteal model was designed by simplifying the process into three production steps, hydrogen storage, and hot briquette iron storage to calculate the energy consumption and material requirements for the hydrogen direct process in Sweden. Additionally, a survey providing insights regarding current practices and perspectives was administered to seven companies in Sweden and two in other European countries, namely the Netherlands and Germany. Furthermore, a comparative analysis of the literature review on life cycle assessment was conducted to compare the carbon emissions associated with two different steel production processes: the conventional process using the basic oxygen furnace and the emerging hydrogen-based steel production process. 

    An analysis of the energy consumption within the hydrogen-based steelmaking process reveals several components, including the electrolyze, direct reduction shaft furnace, electric arc furnace, and briquetted iron and hydrogen storage. The model results showed that electrolyzing alone accounts for 60% of the energy needed in the process. The model showed that hydrogen direct reduction steelmaking needs 3.66 MWH of electricity per ton of liquid steel produced in Sweden.  Only a few of the Swedish companies have adopted innovative approaches while the remaining steel mills primarily rely on scrap-based methods. While they may obtain hydrogen-reduced iron as a raw material in the future, emissions reduction is not their primary focus. These mills contribute to emissions through fuel usage, and efforts are underway to transition from fossil fuels to electricity, bio -based gas, or hydrogen. Hydrogen-based steel production produces significantly lower greenhouse gas emissions than conventional steel productio, by up to 90 percent, depending on the specific process and energy used, as stated in the life cycle analysis reviews. 

    This thesis shows key factors for the success of hydrogen-based steel production methods; low -emission electricity and flexibility to store hydrogen. All three countries have expressed interest in and invested in hydrogen-based steelmaking. the share of renewable energy produced and consumed in hydrogen-based steel production in Sweden is expected to make up a share of 2.3% of the total renewable energy production in the country, while Germany and the Netherlands are projected to contribute a modest 1.5% and 1.3% respectively. However, the search for ways to lower carbon dioxide emissions is costly in terms of the amount of electricity required. There are practical reasons for the restricted usage of this steelmaking process in Europe, including the availability of steel scrap, electricity demand, and the low likelihood of scrap generation and recycling scrap availability on the EU  market. Because of this, it is challenging to predict capacity and carbon dioxide reduction by 2050. 

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  • 50.
    Ambashta, Ritu D.
    et al.
    Bhabha Atom Res Ctr, India.
    Bhatnagar, Amit
    Linnéuniversitetet, Fakulteten för Hälso- och livsvetenskap (FHL), Institutionen för biologi och miljö (BOM).
    Sillanpää, Mika E. T.
    Lappeenranta Univ Technol, Finland.
    Supported iron-based catalysts under influence of static magnetic field for the removal of TBP and EDTA2015Inngår i: Desalination and Water Treatment, ISSN 1944-3994, E-ISSN 1944-3986, Vol. 54, nr 10, s. 2700-2709Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Zerovalent metals offer decontamination of organic toxins in aqueous medium. In the present study, alumina-based iron and iron-nickel in the presence and the absence of magnetic field for the decontamination of tributyl phosphate (TBP) and ethylene diamine tetraacetic acid (EDTA) has been compared. TBP decontamination was improved in the presence of zerovalent metals. EDTA decontamination was not enhanced in the presence of zerovalent metals. The decontamination of TBP using iron-based alumina was higher than iron-nickel. The surface interaction on alumina surface, as characterized by attentuated total reflectance-Fourier transform infrared spectroscopy, and the surface interaction on metallic elements, as characterized by evaluating the magnetic moment values helped to understand the reason for the difference in role of alumina-based iron and iron-nickel on decontamination of TBP and EDTA.

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