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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Feed-in-Tariffs för solceller - ett europeiskt perspektiv applicerat på Sverige

Ghasemi, Arvin January 2013 (has links)
Denna studie granskar tre länder; Tyskland, Spanien och Danmark, som använt feed-in-tariffs (FIT) under en längre tid för att främja elproduktion från solceller. Granskningen omfattar hur användningen sett ut och förändrats, samt om det resulterat i en ökning av solceller. I granskningen ingår också en genomgång av det nuvarande stödsystemet för solceller i Sverige, huruvida det främjat industrin för solceller och om FIT:s skulle kunna användas i Sverige. Granskningens resultat visar att det är svårt att härleda användningen av en viss sorts stödsystem till en ökning av solceller, då det ofta är många olika incitament som används samtidigt. Dessutom kan utformningen av FIT:s skilja sig så mycket att bara användningen av FIT inte garanterar att mängden solceller kommer öka. För att FIT:s ska kunna användas för att främja solcellskapaciteten måste tariffen vara relativt hög, jämfört med exempelvis vindkraft, samt reformeras allteftersom för att hantera de problem som dyker upp på vägen. I Sverige, som sedan 2003 använt elcertifikat och ett investeringsstöd (sedan 2005), har ingen stor ökning av solcellskapaciteten skett jämfört med de andra länderna. Teoretiskt sett kan FIT:s användas i Sverige, men det kräver politisk beslutsamhet, och en justering av elcertifikatssystemet skulle vara mindre komplicerad. / This study analyses three cases where feed-in-tariffs (FIT) have been used, and whether it resulted in an increase of solar cells (PV). The cases were Germany, Spain and Denmark and the examination of these cases included how the use of FIT: s have appeared and changed. Then the current Swedish support system for PV was studied, to see whether the promotion has been successful, and lastly if an FIT-system could be brought into place in Sweden. The results showed that, firstly, it will be hard to trace the use of just one incentive to an increase of PV-installations since most often many incentives are used at once. Secondly, the design of a FIT-system can differ so much that the sole use of FIT: s doesn’t guarantee that PV will grow. For there to be a rise in PV, the tariff must be set relatively high, compared to wind power, and continuously reformed as new problems arise along the way. In Sweden, which since 2003 have used green certificates and an investment aid (since 2005), no significant increase of PV has occurred compared to the other countries. The discussion showed that even though a FIT-system theoretically can be used in Sweden it demands political determination, and that an adjustment or reformation of the certificate system would be less complicated.
72

Collecting rainwater, a comparison between Zambia and Sweden : Can farmers learn from each other? / Uppsamling av regnvatten i Zambia jämfört med Sverige : Kan bönder lära sig av varandra?

Nyxén, Emmy January 2016 (has links)
This thesis investigates if rainwater collection methods in Zambia are efficient compared to methods used in Sweden. Since the climate changes will affect the rainwater distribution in Sweden, with heavy rainfall, storms and droughts, the comparison is necessary to provide methods for future collection and usage of rainwater in Sweden. The investigation includes the collection of rainwater and two methods for the supply of water onto the ground and the plants. The results show that a correctly built dam will create a good supply of water and thus makes a positive impact for the farm. A proper dam can be the key success factor for water supply all year around. One of the key elements for the dam is the collection of rainwater. The results show that in Zambia it is crucial to obtain a solid capacity of water. The results have shown that the techniques used in Zambia can make a positive impact for methods in Sweden for the collection of rainwater. / Denna uppsats undersöker om metoden som används vid uppsamling av regnvatten i Zambia är effektivt samt om det går att använda i Sverige. Eftersom klimatförändringarna kommer att påverka regnvattendistribution i Sverige, med skyfall, stormar och torka är jämförelsen nödvändig för att undersöka metoder för framtida insamling och användning av regnvatten i Sverige. Undersökningen insamlings kapacitet av regnvatten. Resultaten visar att en korrekt byggt damm kommer att skapa en god tillgång på vatten och därmed gör en positiv inverkan på verksamheten. En ordentlig damm kan vara en viktig framgångsfaktor för vattenförsörjning året runt. En av de viktigaste faktorerna för en bra damm är riklig insamling av regnvatten, resultaten visar att i Zambia är det viktigt att erhålla en effektiv vattenförvaring. Resultaten har visat att de tekniker som används i Zambia kan ge en studien studerar metoder i Sverige för insamling av regnvatten.
73

The effects of lime treatment in acidified lakes on sedimentP sorption and productivity

Pilström, Fredrik January 2006 (has links)
In the last century fossil fuel combustion has resulted in acidification and elevated metalcontent in Swedish lakes. To counteract anthropogenic acidification, Sweden began a fullscale liming treatment program in the mid 1970’s. Even though the pH in lime treated lakesincreases after treatment, lake productivity does not always recover. The hypothesis of thisstudy was that increased metal input to the sediment decreases available phosphorus (P) in thewater. In this study, sediment cores were taken from three different types of lakes: limed,limed with fertilizer (added P), and acid (reference) lakes in southwest Sweden to investigatethe possible link between low production (P availability) and sediment metal content inacidified and limed lakes. Sediment was investigated for metal content and experimentalphosphorus (P) additions were conducted to determine P sorption characteristics. Lowequilibrium P concentration and high maximum P sorption in the experiments indicates thatthe sediment will adsorb P from the water column making the already nutrition pore waterless productive, driven mainly by high concentrations of aluminium and iron in sedimentlayers effected by both acidification and lime treatment. There were also indications that limeaddition will elevate P sorbing metals in the sediment of acidified lakes, which can lead toless P in the water column. Perhaps making modification (i.e. P addition) to the treatmentmethod is important for success in restoring acidified lakes.
74

Murgrönsmöja (Ranunculus hederaceus): Uppföljning av populations stärkande insatser inom ÅGP samt analyser av vattenkemi av lokalerna i Halland

Hoffmann, Alice January 2023 (has links)
No description available.
75

Apis mellifera : Gut microbiota variation in individuals from the same hive

Carlsson, Filiph January 2024 (has links)
Apis mellifera are a key contributor to many different and important ecosystems around the world which is something it has in common with other pollinator species. In a very unfortunate turn of events, these pollinator species show a decline in numbers. The decline of which can be partially attributed to human interference through actions that creates habitat loss and pesticide exposure. With the Apis mellifera being an integral part of numerous ecosystems and important for agriculture, their decline is concerning. Research into the Apis mellifera has shown that their gut microbiota has a large impact on their health. With the health of the Apis mellifera being more important than ever before, research into their gut microbiota is of key importance. The aim of this study was to investigate the gut microbiota in different individuals from the same hive and compare them. Investigation of the gut microbiota was achieved through 16S rRNA sequencing of the mid and hindgut with the use of Nanopore sequencing. Results of the sequencing showed high similarities with regards to the bacterial species found, however there were varying proportions of the species in the individuals. The observed similarities were investigated though PCA which confirmed this observation. In conclusion, individuals from the same hive show large similarities in bacterial species with proportions differing being a natural part of the Apis mellifera lifecycle.
76

Identification of target genes for collateral lethality-based cancer treatment

Giffin, Victoria January 2024 (has links)
Copy number alterations are the most commonly observed genome alteration. I sought to find an amplified target for collateral lethality-based treatment that is “hyperactivated” and expressed at a higher rate than expected. Using a list of previously identified hyperactivated genes, I filtered the targets based on function and location, amplification status of various cancer types, and targetability. Oncogenes that were present in the final phase of selection were investigated using data from DepMap to see if their sensitivity to inhibitors increased with expression and copy number. Mouse double minute 2 homolog (MDM2) had a strong correlation increasing sensitivity with both expression and copy number whereas Kirsten rat sarcoma virus (KRAS) had no correlation. The pair were then used as positive and negative controls to see if other genes with low molecular weight inhibitors had the same profile. Lysine Demethylase 5B (KDM5B) and ribosomal protein S6 kinase B1 (RPS6KB1) were identified as possible targets for their correlations in breast cancer and pan-cancer respectively.
77

Understanding Stem-chondrichthyan Dental Development Through Computed Tomography of a Silurian Acanthodian Jaw

Yang, Qianrui January 2024 (has links)
Tracing back Paleozoic taxa to study the origin and structure of jaws and teeth is one of the common means of studying the evolutionary relationships of early vertebrates. It can analyze the oral structure from an anatomical perspective, and the evolution of predatory relationships can also be inferred through such information. Species in different habitats have adapted to specific ecological niches, foraging strategies and defense mechanisms. Therefore, comparing the jaw bones and the arrangement of the teeth is an excellent access point for studying the evolutionary relationships of taxa.  From a morphological point of view, one of the main differences between the oral structures of the two crown-groups of jawed vertebrates (gnathostomes) osteichthyans and chondrichthyans is the arrangement of their teeth and the morphological structure of their lower jaw. According to Dearden and Giles (2021), the mandibles of bony fishes and tetrapods (Osteichthyes) will absorb part of the tooth base and after the teeth are lost, they will be replaced to the outside of the dermal bone and above the endoskeletal jaw cartilage, becoming part of the external tooth arc and the internal tooth arc. Meanwhile, in cartilaginous fish such as sharks, rays and chimaeras, the teeth would grow on the jaw cartilage in a direction that is parallel to the labial tooth and their teeth would also shed and be replaced in this same pattern (Dearden and Giles, 2021). Acanthodians, possibly the earliest gnathostome group, have some shark features and some bony fish features. Recent study indicate that the belong to the chondrichyan stem (Brazeau, 2009), thereby being important for understanding chondrichthyan evolution. However, due to the fact that their unmineralized endoskeletons are rarely fossilized, their evolutionary relationship with modern gnathostomes still leaves a lot of unresolved research to be done, and the structure of their oral structure is one of them.   From the fossil record, it can be tentatively concluded that teeth and jaw bones first appeared in the late Silurian period (approximately 425 million years ago) (Choo, 2014). The subsequent Devonian period (approximately 420-360 million years ago) was the main period of evolution of the growth and replacement mechanism of the mandibular dentition. This period is also when species diversity and functional differentiation of gnathostomes began. Both of these time periods have high research value in the evolutionary history of gnathostomes.  There are many potential reasons for the evolution and diversification of gnathostomes, such as changes in habitat, improvement of defense mechanisms, simplification or complication of food webs, or changes in species' feeding habits (herbivory, carnivory, omnivory, etc.). Comparing and analyzing the changes in the oral structures of gnathostomes in different periods can provide certain explanations for some of the hypotheses (Friedman, 2021).  The existence of computed tomography technology has brought great advancement to the study of anatomical models of jawed vertebrate tooth structures. We can continue to address many questions such as the arrangement of teeth, cartilage structure, and the degree of vascularization of bones through the combination of computed tomography and 3D modeling (Wang, 2019).  This study was based on samples of fossil dental jaw bones from the Silurian collected from Ohessaare cliffs on the island of Saaremaa, Estonia. One specimen was selected and scanned using computed tomography. It was 3D-modelled and compared with available data from younger dental jaw bones from the Devonian-Permian. The anatomical similarities and differences were explored and compared with several jaw bones from different periods (Dearden and Giles, 2021. Rücklin et al., 2021). Placed in a phylogenetic context, this new data was verified to be consistent with the actual results from the previous research on stem-chondrichthyan jaw bones.
78

Development of an automated pipeline for monitoring spatial metabolic dynamics in disease models

Alonso Lois, Miguel January 2024 (has links)
No description available.
79

Finns det en skillnad mellan våra intervjuade fosterbarns/ungdomars och ungdomar i kärnfamiljers framtidsdrömmar?

Ciobanu, Alexandra, Ek, Sofie January 2008 (has links)
<p>Detta arbete kommer att handla om hur fosterbarn känner inför framtiden och om det är skillnad i</p><p>vad det gäller framtidsdrömmar hos barn som växer upp med sina biologiska föräldrar. Vi har</p><p>tittat på vissa lagar som gäller vid fosterhemsplacering, socialtjänstlagen och LVU, och på hur</p><p>socialen arbetar med fosterbarn, och deras uppfattning av om fosterbarn har annorlunda</p><p>framtidsdrömmar till skillnad från ungdomar som växt upp med sina biologiska föräldrar. Vi har</p><p>också intervjuat vuxna som har växt upp i fosterfamilj och hur deras framtidsdrömmar såg ut då.</p><p>Genom ett kvalitativt fältarbete fick vi en bild av att olika ungdomar har olika framtidsdrömmar</p><p>beroende på vilken grundtrygghet de har. Innan arbete startade trodde vi inte att vi skulle få så</p><p>olika svar som vi fick under våra intervjuer, gällande framtidsdrömmar hos ungdomar som växt</p><p>upp i fosterfamilj och de som växt upp med sina biologiska föräldrar. Men vi kom fram till att det</p><p>finns en tydlig skillnad.</p>
80

Hur tas fotosyntesen upp i läroböcker? : - från förr till nu

Ohlsson, Susanne January 2006 (has links)
<p>Denna studie undersöker hur fotosyntesen behandlas i olika läromedel från högstadiet och gymnasiet i ämnet biologi. Även den förändring som skett över tiden har studerats. Studien berör därför läroböcker från 1970-talet fram till 2000-talet. Undersökningen har genomförts med hjälp av studier av en serie högstadieböcker och en serie gymnasieböcker, genomgång av kursplaner och läroplaner, samt intervju med en lärare från gymnasiet. Syftet med att intervjua läraren var att få en inblick i hur denne upplever lärobokens presentation av fotosyntesen. Resultatet visar en förändring i högstadiets biologiläromedel från att ha presenterat biologiska processer på ett faktaspäckat och naturvetenskapligt sätt till ett mera vardagligt och sammanhängande sätt. Gymnasiets läromedel i biologi kurs A bygger från början på en helhetssyn, och genomgår inte samma förändring mot vardag och förenkling som visat sig i högstadiets läromedel.</p>

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