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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.
111

Provtagningsdesign för en populationsgenetisk studie av violgubbe

Johansson, Ida January 2021 (has links)
Population studies have become important tools in conservation biology and genetic analyses are used to investigate genetic diversity within and among populations. Genetic variation can help improve fitness and ecological resilience. However, knowledge about genetic diversity is scarce for most wild species in Sweden. Insight in genetic population structure, can help us understand a species ́ ecological traits and improve species conservation. Fungi are fundamental components in terrestrial ecosystems, yet they have gotten little attention in conservatory work in Europe. In my bachelor thesis, by a short literature review and GIS- analysis of species occurrence data, I have developed a sampling scheme for a conservatory, genetic population study of the threatened pig’s ear mushroom, Gomphus clavatus. The population study aims to investigate genetic structures of the pig’s ear mushroom, in Sweden and surrounding countries. I collected occurrence data from nine countries and processed a total of 3232 findings, which were all compiled in Arcmap. A preliminary selection of localities in Sweden was made through identifying around twenty localities with recent findings, in protected areas. Eight localities of particular interest were included in the selection, one location with findings of morphologically divergent specimens were among those localities. For the surrounding countries, the preliminary selection included localities with findings reported between years 2015–2020. In my literature review, previous studies were not comparable in a way that could guide the design of a sampling scheme for the pig ́s ear mushroom. For clonal species, one should prioritize the total number of localities rather than the number of samples per site, and vice versa for sexually reproducing species. Since the pig ́s ear mushroom belongs in both groups, I suggest a combination of higher density sampling efforts at two localities, together with single sampling at a greater number of geographically distributed localities.
112

Utomhusundervisning och elevers relation till naturen : En intervjustudie med lärare kring deras utomhusundervisning / Outdoor education and pupils’ relation to nature : An interview study with teachers about their outdoor education

Ansmark, Julia January 2020 (has links)
In today’s digitalised society we spend a lot of time indoors, kids included, and not as much time outdoors in nature. Thoughts that might appear because of this include what children’s relation to nature looks like and what we as teachers can do to improve this relation. The purpose of this study is therefore to contribute with knowledge about teachers’ thoughts and use of outdoor education, and how they view pupils’ relation to nature based on their outdoor education. The method used in this study was to conduct interviews with five different teachers about their work with outdoor education, along with their thoughts and views on it. A thematic analysis was used to extract different themes from the teachers’ interview answers. This analysis resulted in six different themes covering teachers’ thoughts and outdoor education. The results show that outdoor education often consists of group-based activities with a focus on practical work where many senses are activated and stimulated. According to the teachers, the way that they work with outdoor education also contributes to a more positive relation between pupils and nature, by improving their interest, but also by giving a better understanding of the interaction between humans, animals and plants, as well as our connection to them. Based on these findings, it is important that teachers try to use more of this kind of outdoor education to help develop and improve the pupils’ relation to nature, while ensuring a productive and healthy environment. / I dagens digitaliserade samhälle spenderar vi mycket av vår tid inomhus, även barnen, och inte lika mycket tid ute i naturen. Tankar som kan komma upp på grund av detta är hur barns relation till naturen ser ut och vad vi som lärare kan göra för att stärka denna relation. Syftet med denna studie är därför att bidra med kunskaper kring lärares tankar och användande av utomhusundervisning samt hur de ser på elevers relation till naturen utifrån sin utomhusundervisning. Metoden som användes för studien var intervjuer med fem olika lärare kring deras arbete med utomhusundervisning och deras tankar och syn kring det. Intervjuerna transkriberades och en tematisk analys användes för att ta fram olika teman i lärarnas intervjusvar. Denna analys resulterade i sex olika teman kring lärares tankar och utomhusundervisning. Resultaten visade att utomhusundervisning oftast innebär arbete i grupp med fokus på ett praktiskt arbetssätt där många sinnen aktiveras och stimuleras. Detta sätt som lärare arbetar med utomhusundervisning på bidrar, enligt lärarna, även till positivare relationer mellan elever och naturen genom ökat intresse samt förståelse och känsla för samspelet som finns mellan människor, djur och växter. Utifrån det som framkommit ur denna studie är det viktigt för elevers relation till naturen att lärare försöker att använda sig mer av utomhusundervisning, med förutsättning att de jobbar på det sätt som beskrivs.
113

The wood-inhabiting fungal community on standing dead birches : a comparison of ring-barked and naturally dead trees / Vedlevande svampar på stående döda björkar : en jämförelse mellan ringbarkade och naturligt döda träd

Persson, Samuel January 2022 (has links)
Dead wood is an important part of forest ecosystems, especially since so many organisms depend on it for nutrients or as substrate for breeding or foraging. Since forestry intensified in northern Europe during the mid 1900s, the amount of dead wood in Fennoscandian forests has drastically decreased. For wood-inhabiting organisms such as fungi, this has led to changes in the community composition with many species becoming rare and threatened by extinction. To increase the volume of dead wood, restoration actions aim to create dead wood artificially by for example prescribed burning or by ring-barking trees. In coniferous forests, artificially created dead wood is known to be colonized by many wood-inhabiting fungi, indicating that it can work as a substitute of naturally dead wood. There is, however, a shortage for similar studies in deciduous forests and especially birch dominated ones. In this study, we examine the wood-inhabiting fungal community composition on standing dead wood of birches in east central Sweden. Data was collected with single surveys of fruitbody presence on both ringbarked and naturally dead trees during late autumn. We found that there is a difference in the fungal community composition between the dead wood categories, with form groups of Corticoids and Pyrenomycetes being significantly more abundant on ring-barked birches thanon naturally dead birches. This includes species such as Stereum rugosum and Jackrogersella multiformis. A total of 41 fungal species were observed in this study, out of which 30 species were observed on ringbarked trees and 31 species observed on naturally dead trees. The most observed species was Fomes fomentarius, which appeared numerously on trees of both deadwood categories. Our results indicated that the presence of Fomes fomentarius correlate with lower foraging activity of woodpeckers. However, further research is needed to evaluate if fungal species can be used as indicators for successful restoration actions in relation to the activity of insects and foraging woodpeckers. We conclude that ring-barked birches work well as suitable substrate for many fungal species and that ring-barking as a restoration action is useful for the community of wood-inhabiting fungi.
114

Analys av bipollensorter i Västerbotten : Betydelse och för- och nackdelar med klassiska morfologiska metoder / Pollen grain analysis in Västerbotten, Umeå : Pros and cons using classic morphological methods

Persson, Jesper January 2021 (has links)
Composition of pollen pellets foraged by honeybees, sampled in Degernäs and Tavelsjö, Västerbotten County, during early summer 2020, is used to explore if honeybees are monofloral or polyfloral. Samples from different days and different colours were evaluated by light microscopy. Each unique pollen species in each pellet was morphologically identified with help of an international pollen database (PalDat) and a common bee plant document, using light microscopy and scanning electron microscope photographs. A selection of pollen species were identified down to species level and were used to explore which wild pollinators can also pollinate these plant species, to speculate around possible competition scenarios between them and honeybees. SEM and DNA extraction were performed with a selection of the pollen pellets and with the extracted DNA, different PCR primers targeting different plant gene markers were tested to see which ones worked with pollen from northern Sweden. More detailed pictures of the pollen grains were seen in SEM which helped ease the species identification of some of them. The results showed that only a few of the pollen pellets had only one detected plant species while the rest had 2 or more plant species in them. Thus, these data indicate that the honeybees in Degernäs and Tavelsjö are polyfloral, at least for the samples studied in this bachelor thesis. Methods are evaluated and the findings were that a combination of morphological and molecular biology studies are both needed to be able to establish a new updated pollen database for northern Sweden.
115

An Unrecoverable Sleep Deficit : A literary analysis of Adolescents’ sleep loss and the consequences of sleep deficit regarding academic performance

Åhs, Hugo January 2020 (has links)
There is a noticeable difference in the debate regarding adolescents’ sleep patterns between the biological clock and society’s clock when we talk about adolescents. Sleep scientists or somnologists, are alarming as more evidence reach the surface that young people are not getting the recommended sleep that is required to perform academically well. Not only are there direct connections between sleep deficit and academic performance, but sleep deficit also takes a critical toll upon their physical and mental health. The problem is that adolescents’ circadian cycle is postponed with a few hours compared to children and adults. This results in a major sleep deficit when adolescents must adjust to societal rhythms and habits – a clock they are not programmed biologically to follow. Adolescents must attend to school in the early morning, when in reality their needs point to that school times in fact should start around 10:00. Society’s view has traditionally been that teenagers are lazy but in fact evidence does prove that it may not be the case. The following essay will therefore serve as an informative update to what has been stated by somnologists and raise awareness regarding adolescents and what happens when they are exposed to a chronic sleep deficit put on them by society.
116

Neural correlates of romantic love and romantic attachment

Berg Junker, Maria Constance January 2018 (has links)
In the field of neuroscience, being in love and feeling romantically attached to a partner is described as a dynamic process. Romantic love may be viewed as a motivational system, changing throughout time and place, fluctuating on the interest and motivation of the individual. Early memories and attachment towards a caregiver, lay the foundation for later attachment behavior, also known as attachment styles. In this thesis, an exploratory approach is present. The thesis aims to introduce and describe the neural correlates of romantic love and romantic attachment. Brain regions concerned with reward, emotion and thought processing, such as the reward circuitry network of the brain and the limbic system, are being investigated. So are other brain areas involved in romantic love and romantic attachment. Research findings suggest that brain areas responsible for affection, emotional control, learning, memory and social judgment are all involved in the complex processes of being in love and feeling romantically attached. These findings are represented by the involvement of the frontal lobe, cerebral cortex, limbic system, orbitofrontal cortex, and hippocampus, anterior cingulate cortex (ACC), ventral tegmental area (VTA), caudate tail, including the reward pathways of the brain. Distribution and regulation of neurotransmitters such as; vasopressin, oxytocin, dopamine, corticosterone and serotonin are all present in the state of romantic  attachment and romantic love. Overlapping evidence confirms the involvement of the reward circuitry network, together with the limbic system as crucial in the formation and maintenance of a romantic relationship.
117

Effekter av intra- och interspecifik konkurrens på den reproduktiva framgången hos spansk skogssnigel, Arion vulgaris / The effects of intra- and interspecific competition on the reproductive success of the Spanish slug, Arion vulgaris

Johansson, Sandra January 2022 (has links)
Reproductive success can be influenced by interspecific and intraspecific competition, which consequently affect the distribution of species. The Spanish slug (Arion vulgaris) is an invasive terrestrial gastropod originating from southern Europe, and it causes substantial damage to horticulture and agriculture in Sweden.The leopard slug (Limax maximus) has been documented to have negative effects on the reproductive success of other slugs. Therefore, it has been suggested that the local distribution of the Spanish slug can be regulated by interspecific competition from leopard slugs. This competitive effect was tested in a laboratory experiment using mesocosms. The experiment had three different treatments: (1) two Spanish slugs, (2) four Spanish slugs and (3) two Spanish slugs and two leopard slugs. There was a significant effect of treatment on egg mass, where higher densities of slugs resulted in lower egg mass. Furthermore, there was a positive effect of body mass on the total number of eggs, mass, and size of the eggs. However, there was no clear effect of density of slugs on the size of the eggs produced and there was no difference between intra- and interspecific competition on the reproductive success of the Spanish slug. Because the level of intra- and interspecific competition on eggs laying was similar, my study does not support the hypothesis that leopard slugs can control Spanish slug populations, but it does show that intraspecific competition likely regulate egg production. / Reproduktiv framgång kan påverkas av inter- och intraspecifik konkurrens vilket i förlängningen kan påverka lokal utbredning. Spansk skogssnigel (Arion vulgaris) är en invasiv snigel som härstammar från sydeuropa och orsakar omfattande skador på trädgårdar och jordbruk i Sverige. Pantersnigeln (Limax maximus) har visat sig ha negativ påverkan på andra sniglars äggläggning. Min studie undersöker om interspecifik konkurrens från pantersnigeln har större effekt på spansk skogssnigels äggläggning än den från intraspecifik konkurrens från artfränder. Pantersnigeln kan då verka som en begränsande faktor för den spanska skogssnigelns lokala utbredning. För att undersöka detta utfördes ett experiment där individer av de båda arterna hölls i mesokosmer i olika tätheter och kombinationer i tre olika behandlingar: (1) två spanska skogssniglar, (2) fyra spanska skogssniglar och (3) två spanska skogssniglar och två pantersniglar. Experimentet visade tydligt att täthet av sniglar hade en effekt på de lagda äggens massa, och det fanns en positiv effekt av sniglars kroppsmassa på äggens storlek, antal och massa. Däremot fanns det ingen effekt av snigeltäthet på äggens storlek. Vidare hade intraspecifik konkurrens lika stor effekt på äggläggningen hos spansk skogssnigel som interspecifik konkurrens från pantersniglar. Min studie stödjer därför inte hypotesen att leopardsniglar kan kontrollera populationer av spansk skogssnigel, men den visar däremot att intraspecifik konkurrens påverkar äggläggningen.
118

Toxicological screening of imidazolium based ionic liquids

Stenström, Joakim January 2020 (has links)
Ionic liquids are salts that are in liquid form at room temperature. These compounds have been suggested to be environmentally friendly and are proposed to be replacements for commercially available solvents used in laboratory operations today. There is an increasing interest in these compounds, but toxicological data of ionic liquids are still scarce. In this project five imidazolium based ionic liquids, 1-etyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, 1-hexyl-3-methylimidazolium, 1-octyl-3-methylimidazolium and 1-decyl-3-methylimidazolium were evaluated based on responses on aryl hydrocarbon receptor (DR-Ecoscreen), Nrf2 activity (MCF732cARE), androgen receptor (AR-Ecoscreen) and estrogen receptor (VM7Luc4ER). This was done with an effect based in vitro approach using luciferase bioassays. The results show that imidazolium based ionic liquids have the ability to induce androgen and estrogen receptor activity. It is also shown that imidazolium based ionic liquids can act as antagonists on the androgen receptor. Imidazolium based ionic liquids does not seem cause oxidative stress and is shown to not interact with the aryl hydrocarbon receptor. The ability of 1-octyl-3-methylimidazolium and 1-decyl-3-methylimidazolium to pass the gastrointestinal tract was also tested in a modified transwell caco-2 permeability test, which resembled the human GI-tract. It was shown to be difficult to evaluate if 1-octyl-3-methylimidazolium and 1-decyl-3-methylimidazolium have the ability to pass through the GI-tract and antagonize on the androgen receptor. These results are important from both an environmental as well as human health point of view if imidazolium based ionic liquids are to be accidentally or intentionally release into the environment.
119

Inventering av floran på Hagöns naturreservat: En undersökning av effekten av ljungbränning och betesdrift.

Zetterberg, Anders January 2023 (has links)
Ljungheden i Sverige är ett landskap som gått från att prägla det Halländska landskapettill att nu finnas som rester längsmed kusten och inåt land. Den unika flora som ärknuten till dessa hedar är nu hotade. Ljungheden idag sköts med bränning och bete ochman strävar efter att ha en mosaikartad skötsel.Hagön är ett naturreservat som ligger söder om Halmstad och är ett av de mest artrika iHalland med höga naturvärden.I denna rapport undersöks effekterna av skötselåtgärderna bete och ljungbränning påvegetationen i naturreservatet Hagön genom att jämföra tre olika ljungsuccessioner medvarandra. Även en kartläggning av Ljungögontröstens och Kärrknipprotens utbredning ireservatet görs efter intresse från Halmstad kommuns sida.Inventeringen gjordes genom att kartlägga ljungens höjd med ögonmått och därefterdela in den i zoner efter ljunghöjd. En låg, medel och hög zon. Därefter inventeradeszonerna i två gånger två meters rutor som slumpades ut på respektive zon.Skillnader mellan arter, ljunghöjd och täckningsgrad ljung mättes och resultatet visadeatt det fanns en skillnad mellan zonerna. Ingen skillnad fanns mellan antal arter ochljunghöjd eller mellan antal arter och ljunghöjd i zon 1 (låg) och zon 2 (medel), men izon 3 (hög) fanns en negativ korrelation mellan täckningsgrad av ljung och artantal.Ljungögontröst inventerades i reservatet och hittades längs med sanddynerna och längrener i reservatet. Kärrknipprot fanns mest i den södra inhägnaden där jag uppmätte 5-7fröställningar per kvadratmeter.Artantalet var lägst i zonen med mest ljungtäckning (zon 3) medan artantalen i låg- ochhögzonerna var betydligt högre.Det kan förklaras med att det efter bränning skapas blottor för örtväxter att gro ochfrodas ett tag innan ljungen kommer tillbaka.
120

"Jag får alltid lite ångest av att prata om och tänka på framtidens klimat" : Gymnasieelevers syn på sin klimatpåverkan och klimatångest, samt på skolans undervisning av miljö, klimat och hållbar utveckling / "I always get a bit anxious talking and thinking about the future climate" : Upper secondary school students' perceptions regarding their climate impact and climate anxiety, as well as their perspectives on environmental, climate, and sustainable development education within school

Nilsson, Johanna January 2024 (has links)
Illavarslande rubriker om klimatet och klimatångest har blivit allt vanligare i dagens samhälle. Debatter och diskussioner om global uppvärmning, klimatförändringar och konsekvenser av dessa verkar endast stiga i intresse. Engagemanget sprider sig bland samhällsmedborgare och likaså verkar, enligt många alarmerade rubriker, även negativa känslor kopplat till klimatet spridas. Klimatångest har blivit ett begrepp som florerar i forskning och vardagliga situationer allt mer. Forskning visar att klimatångest kan drabba alla, men kanske värst barn och unga. Samma ungdomar som de alarmerande rubrikerna syftar till befinner sig också i skolan där detta är ett viktigt och nödvändigt inslag. Frågeställningarna i examensarbetet syftar till att undersöka vilken medvetenhet och inställning gymnasieungdomar, som läser naturkunskap, har till frågor om miljö, klimat och hållbar utveckling. Frågeställningarna undersöker också i vilken utsträckning dessa gymnasieungdomar känner klimatångest, hur de upplever skolans undervisning och hur detta påverkar deras lust att lära sig mer om miljö, klimat och hållbar utveckling. Undersökningen genomfördes med en digital enkät som totalt besvarades av 123 naturkunskapselever i olika årskurser på gymnasiet. Resultatet visar att många elever anser sig ha en klimatpåverkan och kunna reflektera över denna. Vissa skillnader i medvetenhet och kunskap framkommer mellan de olika årskurserna där de äldre eleverna bedöms ha en mer nyanserad bild av klimatläget. Det framkommer även att många elever känner en oro och ångest kopplat till klimatet, men att ordet ”ångest” är ett starkt känsloladdat ord och att många skolungdomar hellre använder ordet ”oro”. Trots, eller kanske tack vare, elevernas i många fall negativa känslor kopplat till området anser de undervisningen som viktig, meningsfull och nödvändig för att öka förståelsen och lösa klimatkrisen. Många elever vill att skolan ska undervisa ännu mer om klimatet och ha ett större fokus på lösningar av klimatkrisen eftersom undervisningen tenderar att bli ångestladdad när den kopplas till negativa konsekvenser i det aktuella och framtida läget.

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