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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.
21

Structure and Function in Plant Ä12 Fatty Acid Desaturases and Acetylenases

Gagne, Steve Joseph 22 December 2008 (has links)
This study provides insight into the structure/function relationship between desaturases and acetylenases, and indicates amino acid residues within acetylenases which influence reaction outcome. <i>Oleate desaturases</i> belong to a family of enzymes capable of introducing cis double bonds between C12 - C13 in oleate esters. Acetylenases are a subset of oleate desaturase enzymes which introduce a triple bond in the C12 - C13 position of linoleate. To better understand which amino acids could be responsible for differentiating the activity of acetylenases from typical desaturases, a total of 50 protein sequences were used to compare the two classes of enzymes resulting in the identification of 11 amino acid residues which are conserved within either separate family but differ between the two groups of enzymes. These identified amino acid residues were then singularly altered by site-directed mutagenesis to test their role in fatty acid modification. Specifically, the wild type acetylenase, Crep1 from <i>Crepis alpina</i>, and a number of point mutants have been expressed in <i>Saccharomyces cerevisiae</i>, followed by fatty acid analysis of the resulting cultures. Results indicate the importance of 4 amino acid residues within Crep1 (Y150, F259, H266, and V304) with regards to desaturase and acetylenase chemoselectivity, stereoselectivity, and/or substrate recognition. The F259L mutation affected the acetylenase by converting it to an atypical FAD2 capable of producing both cis and trans isomers. The V304I mutation resulted in the conversion of Crep1 into a stereoselective FAD2, where only the cis isomers of 16:2 and 18:2 were produced. The Y150F mutation led to a loss of acetylenase activity without affecting the inherent desaturase activity of Crep1. The H266Q mutation appears to affect substrate selection causing an inability to bind substrate (16:1-9c and/or 18:1-9c) in a cisoid conformation, resulting in an increased accumulation of trans product. The changes in enzyme activity detected in cultures expressing Crep1 mutants demonstrate the profound effect that exchanging as little as one amino acid can have on an enzyme properties. Enzymes retain some conservation of amino acids necessary for activity, such as those involved in metal ion binding, whereas subtle changes can affect overall enzyme function and catalysis.
22

Genetics and ecology of natural populations

Lundqvist, Elisabeth January 2002 (has links)
I have studied the genetic variation of single species using morphological variation and enzyme electrophoresis. I have striven to understand the interaction between the breeding structure and the ecology of the species in relation to the community, in which it lives. The work was done in the county of Västerbotten, northern Sweden. In the Skeppsvik archipelago I have studied the population structure of Silene dioica: ecotypic variation in other populations. I have also studied the genetic diversity of Angelica archangelica, Bistorta vivipara, Viscaria alpina and the earthworm Eiseniella tetraedra along the free-flowing Vindel and Sävar Rivers and the regulated Urne River. The island populations of S. dioica are subdivided into several breeding units and levels of differentiation among subpopulations within islands were about twice as high as among islands. Restricted seed and pollen dispersal creates patches made up of related individuals that may diverge as a result of drift. Frequent seed and pollen dispersal occurs among islands and they will receive the same alleles. This may explain the pattern of differentiation observed. In contrast, the patches within islands may be founded by only a few individuals. * S. dioica exhibits morphological differentiation in vegetative and floral characters between serpentine, cold spring, rich forest and coastal habitats. There was no association between  genetic and geographical distance or between genetic distance and habitat. Serpentine and cold spring, which represented the most extreme habitats were also most differentiated. Populations of S. dioica are subject to herbivory; predation may exert a selective pressure on vegetative characters. A number of selective forces such as pollinators and fungal parasites act on reproductive characters. Assuming that water dispersal is important I tested several hypotheses to explain patterns of genetic diversity expected to be exhibited by riparian organisms along free-flowing and regulated rivers. I show that dispersal, distribution and breeding structure are important determinants of the evolution of the riparian flora. Patterns of genetic diversity may be exhibited at many spatial scales, e.g. among entire rivers, and between types of riverbanks within a river reach. Populations must be sampled at a spatial scale relevant to the hypothesis to be tested. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 2002, härtill 5 uppsatser.</p> / digitalisering@umu
23

Molecular breeding and biochemical characterization of an oleaginous fungus Mortierella alpina for prostaglandin F2α production / プロスタグランジンF2αの生産に向けた油糧糸状菌Mortierella alpinaの分子育種と生化学的解析

Mohd, Fazli Bin Farida Asras 25 March 2019 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第21821号 / 農博第2334号 / 新制||農||1067(附属図書館) / 学位論文||H31||N5193(農学部図書室) / 京都大学大学院農学研究科応用生命科学専攻 / (主査)教授 小川 順, 教授 植田 充美, 教授 栗原 達夫 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
24

Lichen species richness, diversity, and evenness in Alpine and Antarctic deglaciated areas / Lavarternas rikedom, mångfald och jämnhet i Alpina och Antarktiska områden efter glaciärernas reträtt

Meier, Karin January 2024 (has links)
Retreating glaciers are leaving behind deglaciated areas, lacking biological life, presenting opportunities for specialist species to colonize. Lichens possess the ability, due to the symbiosis with nitrogen fixating photobionts, to colonize these deglaciated areas even in harsh environments like in the European Alps or maritime Antarctica. I hypothesized that there are no differences in lichen species richness, diversity, and evenness in deglaciated areas within four Alpine glaciers as well as four Alpine glaciers and one Antarctic glacier, yet there are differences between four successional zones in the same areas. Furthermore, there are no lichen species that colonize both the European Alps and Antarctica. Study sites consisted of Morteratsch Glacier, Gaisbergferner Glacier, Rötkees Glacier and Pasterze Glacier in the Alps as well as McLeod Glacier on Signy Island, South Orkney Islands, Antarctica. Four indexes were calculated: alpha diversity, Shannon Index, Menhinicks Index and Pielou Index and compared with Anova and Kruskal-Wallis tests. The results showed no significant differences for the species richness, diversity, and evenness of lichen species for the Alpine and Antarctic study sites yet there were differences found between the successional zones. Four lichen species were found in all the Alpine study sites, yet no common lichen species were present in the Alpine and Antarctic sites. Environmental conditions differ between the Alps and Antarctica which is reflected in the anomaly of the Menhinicks Index and furthermore, sexual, or vegetative reproduction influences lichen species present. The successional zones did not follow the chronological order since deglaciation which might reflect an increase in species competition as vegetation develops under time. Lichen species are understudied, and further research might not only give insights into inner processes in lichens but also about how to survive in extreme environments. / Glaciärer som drar sig tillbaka lämnar efter sig områden som saknar biologiskt liv, vilket skapar möjlighet för specialister att inta dessa områden. Lavar har förmågan att kolonisera sådana isfria områden på grund av sin symbios med kväve-fixerande fotobionter även om miljöerna är hårda som i den europeiska Alperna eller det maritima Antarktis. Mina hypoteser är att det inte finns skillnader i lavarnas artrikedom, diversitet och jämnhet i de områden som nyligen blivit isfria inom fyra alpina glaciärer samt mellan de fyra alpina glaciärerna och en antarktisk glaciär men att det finns skillnader mellan fyra successionala zoner i samma områden. Vidare finns det inga lavarter som koloniserar båda Alperna och Antarktis. Studieområdena bestod av: Morteratsch-glaciär, Gaisbergferner-glaciär, Rötkees-glaciär och Pasterze-glaciär i Alperna samt McLeod-glaciär på Signyön, Syd Orkneyöarna, Antarktis. Fyra index beräknades: alfa diversitet, Shannon Index, Menhinicks Index och Pielou Index och jämfördes med Anova och Kruskal-Wallis testerna. Resultaten visade inga signifikanta skillnader för artens rikedom, mångfald och jämnhet av lavarterna för lavarter i alpina och antarktiska studieområdena, men det fanns skillnader mellan de successionella zonerna. Fyra lavarter hittades på alla alpina studieplatser, men inga gemensamma lavarter fanns på de alpina och antarktiska platserna. Miljöförhållanden skiljer sig mellan Alperna och Antarktis, vilket syns i avvikelsen av Menhinicks Index och dessutom påverkar sexuell eller asexuell reproduktion förekomsten av lavarter. Successionszonerna följde inte den kronologiska ordningen efter reträtten av glaciärerna vilket kan återspegla en ökning av artkonkurrensen när vegetationen utvecklar sig över tiden. Lavarna är underforskade och ytterligare forskning kan ge upplysningar i interna processer men även insikter kring hur överlevnad blir säkerställd i extrema miljöer.
25

Research on thermal modification of African alpine bamboo (Yushania alpina [K. Schumann] Lin) in terms of woven strand board (WSB) product development in Ethiopia

Starke, Robert 17 September 2015 (has links) (PDF)
’African Bamboo PLC’ has the vision to become the first and the leading bamboo-based floorboard producer in Africa with export markets in Europe and America. African alpine bamboo (Yushania alpina), common in the highlands of Ethiopia, was used to develop woven strand board (WSB) products. Research on thermal modification was part of the product development. Samples were mainly collected in Tetechia (6°33‘ 34‘‘ N 38°32‘25‘‘ W, 2,650-2,700 m a.s.l.), located in the Sidama region. Three culms each of two, three, four and five years of age were harvested. Samples were taken from the middle of each internode to determine the moisture content and density. Samples used to assess the effects of thermal modification were cut next to them. Further test specimens from different areas and other species such as the lowland bamboo (Oxytenanthera abyssinica) were also investigated. The thermal treatment was applied in a kiln with steam as an inert blanket to reduce oxidative processes. Eight modifications were performed at temperatures of 160 °C, 180 °C, 200 °C and 220 °C, at durations of three or five hours each. Mass loss, sorption behaviour, impact resistance, resistance to indentation and contents of chemical components were analysed for the modified and unmodified samples. Yushania alpina is a thin-walled bamboo with a maximum diameter of 6 cm, moisture content of up to 150 % and densities of between 0.5 g/cm² and 0.8 g/cm². Moisture content, diameter and wall thickness decreased from the bottom to the top of the culms, whereas density increased. Two year old bamboo had the lowest and three year the highest density. The mass loss followed an exponential trend, with about 2 % loss at 160 °C and 16 % at 220 °C. This mainly reflected the degradation of hemicellulose, which was fully removed at 220 °C. Extractive contents, at less than 5 %, fluctuated. Lignin amounted to 30 % and increased appreciably. Cellulose reached contents of about 45 % and decreased slightly at high temperatures. The chemical change, which was based more on the temperature than on the duration of treatment, influenced the sorption behaviour and mechanical properties most of all. The equilibrium moisture content was reduced by between 10 % to 40 %, depending on the climate and modification temperature chosen. This reduction stabilised between temperatures of 200 °C and 220 °C. The impact resistance of untreated bamboo was 3.8 J/cm², compared to only 1.4 J/cm² for modified samples. Resistance also differed between samples from the outer and inner part of the culm in the transverse section. The resistance to indentation declined also. Unmodified samples had 47 N/mm², compared to only 20 N/mm² for strongly modified samples. The results of the analysis and the experience gained indicate that temperatures between 180 °C and 200 °C, held for three hours, lead to the best results for woven strand board production using Ethiopian highland bamboo. / ’African Bamboo PLC’ setzt sich zum Ziel, als erstes Unternehmen Holzwerkstoffe aus Bambus nach Europa und Amerika zu exportieren. Afrikanischer Hochgebirgsbambus (Yushania alpina), welcher vor allem im Hochland von Äthiopien vorkommt, wurde dazu verwendet ”woven strand boards” (WSB) zu entwickeln. Untersuchungen zur thermischen Modifizierung waren dabei Bestandteil der Produktentwicklung. Die dafür notwendigen Bambusproben wurden hauptsächlich in Tetechia (6°33‘34‘‘ N 38°32‘25‘‘ W, 2650-2700 m ü. NN), einem Dorf in Sidama, entnommen. Es wurden dazu je drei Bambushalme der Altersklassen zwei, drei, vier und fünf Jahre geerntet. Proben für die Bestimmung von Holzfeuchte und Dichte wurden in der Mitte jedes Internodiums entnommen. Diese spielten als Referenzprobe eine große Rolle. Neben den Referenzprobekörpern wurden die jeweiligen Stücke für die thermische Behandlung heraus gesägt, wobei dies nach einer bestimmten Systematik erfolgte. Neben den Proben aus Tetechia wurden für die Untersuchungen zudem Proben aus anderen Gebieten und von einer anderen Art, dem Tieflandbambus (Oxytenanthera abyssinica), hinzugefügt. Die thermische Modifizierung erfolgte unter Wasserdampf, welcher oxidative Prozesse verhinderte. Insgesamt erfolgten acht Modifizierungen bei Temperaturen von 160 °C, 180 °C, 200 °C und 220 °C und einer jeweiligen Haltezeit von drei oder fünf Stunden. In Anbetracht der unbehandelten und behandelten Proben wurden der Masseverlust, die Bruchschlagarbeit, der Eindruckswiderstand und die chemische Zusammensetzung analysiert. Yushania alpina ist ein dünnwandiger Bambus mit Durchmessern bis zu 6 cm, Holzfeuchten bis 150 % und Dichten zwischen 0,5 g/cm² und 0,8 g/cm². Holzfeuchte, Durchmesser und Wandstärke verringerten sich mit der Halmhöhe, wobei die Dichte hingegen anstieg. Zweijähriger Bambus hatte die geringsten und dreijähriger Bambus die höchsten Dichten. Der Masseverlust folgte einem expontiellem Verlauf mit Werten von 2 % bei 160 °C und 16 % bei 220 °C. Er widerspiegelte den Abbau der Hemicellulose, welche bei 220 °C schon nicht mehr vorhanden war. Exktraktgehalte fluktuierten mit Werten unter 5 %. Der Ligningehalt lag bei ungefähr 30 % und stieg merklich an. Der Cellulosegehalt erreichte Werte von etwa 45 %, wobei die Cellulose bei höheren Temperaturen leicht abgebaut wurde. Die chemischen Veränderungen, welche maßgeblich von der angewandten Temperatur statt der Behandlungsdauer beeinflusst wurden, wirkten sich auf das Sorptionsverhalten und mechanische Eigenschaften aus. Je nach ausgesetztem Klima und erfolgter Modifikation wurde die Ausgleichsfeuchte der Proben um 10 % bis 40 % reduziert. Die Abnahme der Ausgleichsfeuchte stabilisierte sich im Temperaturbereich von 200 °C bis 220 °C. Die Bruchschlagarbeit des unbehandelten Bambus betrug 3,8 J/cm², die des behandelten nur 1,4 J/cm². Die Bruchschlagarbeit variierte unabhängig von der Modifikation zwischen dem inneren und äußeren Abschnittes innerhalb des Halmquerschnitts. Der Eindruckswiderstand nahm mit der thermischen Behandlung ebenfalls ab. Unbehandelte Proben hatten 47 N/mm², während die modifizierten Proben nur noch 20 N/mm² aufwiesen. Anhand der Ergebnisse und erworbenen Erfahrungen lies sich schlussfolgern, dass Temperaturen zwischen 180 °C und 200 °C bei einer Haltezeit von drei Stunden für die thermische Modifizierung von Äthiopischem Hochlandbambus in Bezug auf die Entwicklung von ”woven strand boards” empfehlenswert waren.
26

Research on thermal modification of African alpine bamboo (Yushania alpina [K. Schumann] Lin) in terms of woven strand board (WSB) product development in Ethiopia

Starke, Robert 11 September 2014 (has links)
’African Bamboo PLC’ has the vision to become the first and the leading bamboo-based floorboard producer in Africa with export markets in Europe and America. African alpine bamboo (Yushania alpina), common in the highlands of Ethiopia, was used to develop woven strand board (WSB) products. Research on thermal modification was part of the product development. Samples were mainly collected in Tetechia (6°33‘ 34‘‘ N 38°32‘25‘‘ W, 2,650-2,700 m a.s.l.), located in the Sidama region. Three culms each of two, three, four and five years of age were harvested. Samples were taken from the middle of each internode to determine the moisture content and density. Samples used to assess the effects of thermal modification were cut next to them. Further test specimens from different areas and other species such as the lowland bamboo (Oxytenanthera abyssinica) were also investigated. The thermal treatment was applied in a kiln with steam as an inert blanket to reduce oxidative processes. Eight modifications were performed at temperatures of 160 °C, 180 °C, 200 °C and 220 °C, at durations of three or five hours each. Mass loss, sorption behaviour, impact resistance, resistance to indentation and contents of chemical components were analysed for the modified and unmodified samples. Yushania alpina is a thin-walled bamboo with a maximum diameter of 6 cm, moisture content of up to 150 % and densities of between 0.5 g/cm² and 0.8 g/cm². Moisture content, diameter and wall thickness decreased from the bottom to the top of the culms, whereas density increased. Two year old bamboo had the lowest and three year the highest density. The mass loss followed an exponential trend, with about 2 % loss at 160 °C and 16 % at 220 °C. This mainly reflected the degradation of hemicellulose, which was fully removed at 220 °C. Extractive contents, at less than 5 %, fluctuated. Lignin amounted to 30 % and increased appreciably. Cellulose reached contents of about 45 % and decreased slightly at high temperatures. The chemical change, which was based more on the temperature than on the duration of treatment, influenced the sorption behaviour and mechanical properties most of all. The equilibrium moisture content was reduced by between 10 % to 40 %, depending on the climate and modification temperature chosen. This reduction stabilised between temperatures of 200 °C and 220 °C. The impact resistance of untreated bamboo was 3.8 J/cm², compared to only 1.4 J/cm² for modified samples. Resistance also differed between samples from the outer and inner part of the culm in the transverse section. The resistance to indentation declined also. Unmodified samples had 47 N/mm², compared to only 20 N/mm² for strongly modified samples. The results of the analysis and the experience gained indicate that temperatures between 180 °C and 200 °C, held for three hours, lead to the best results for woven strand board production using Ethiopian highland bamboo. / ’African Bamboo PLC’ setzt sich zum Ziel, als erstes Unternehmen Holzwerkstoffe aus Bambus nach Europa und Amerika zu exportieren. Afrikanischer Hochgebirgsbambus (Yushania alpina), welcher vor allem im Hochland von Äthiopien vorkommt, wurde dazu verwendet ”woven strand boards” (WSB) zu entwickeln. Untersuchungen zur thermischen Modifizierung waren dabei Bestandteil der Produktentwicklung. Die dafür notwendigen Bambusproben wurden hauptsächlich in Tetechia (6°33‘34‘‘ N 38°32‘25‘‘ W, 2650-2700 m ü. NN), einem Dorf in Sidama, entnommen. Es wurden dazu je drei Bambushalme der Altersklassen zwei, drei, vier und fünf Jahre geerntet. Proben für die Bestimmung von Holzfeuchte und Dichte wurden in der Mitte jedes Internodiums entnommen. Diese spielten als Referenzprobe eine große Rolle. Neben den Referenzprobekörpern wurden die jeweiligen Stücke für die thermische Behandlung heraus gesägt, wobei dies nach einer bestimmten Systematik erfolgte. Neben den Proben aus Tetechia wurden für die Untersuchungen zudem Proben aus anderen Gebieten und von einer anderen Art, dem Tieflandbambus (Oxytenanthera abyssinica), hinzugefügt. Die thermische Modifizierung erfolgte unter Wasserdampf, welcher oxidative Prozesse verhinderte. Insgesamt erfolgten acht Modifizierungen bei Temperaturen von 160 °C, 180 °C, 200 °C und 220 °C und einer jeweiligen Haltezeit von drei oder fünf Stunden. In Anbetracht der unbehandelten und behandelten Proben wurden der Masseverlust, die Bruchschlagarbeit, der Eindruckswiderstand und die chemische Zusammensetzung analysiert. Yushania alpina ist ein dünnwandiger Bambus mit Durchmessern bis zu 6 cm, Holzfeuchten bis 150 % und Dichten zwischen 0,5 g/cm² und 0,8 g/cm². Holzfeuchte, Durchmesser und Wandstärke verringerten sich mit der Halmhöhe, wobei die Dichte hingegen anstieg. Zweijähriger Bambus hatte die geringsten und dreijähriger Bambus die höchsten Dichten. Der Masseverlust folgte einem expontiellem Verlauf mit Werten von 2 % bei 160 °C und 16 % bei 220 °C. Er widerspiegelte den Abbau der Hemicellulose, welche bei 220 °C schon nicht mehr vorhanden war. Exktraktgehalte fluktuierten mit Werten unter 5 %. Der Ligningehalt lag bei ungefähr 30 % und stieg merklich an. Der Cellulosegehalt erreichte Werte von etwa 45 %, wobei die Cellulose bei höheren Temperaturen leicht abgebaut wurde. Die chemischen Veränderungen, welche maßgeblich von der angewandten Temperatur statt der Behandlungsdauer beeinflusst wurden, wirkten sich auf das Sorptionsverhalten und mechanische Eigenschaften aus. Je nach ausgesetztem Klima und erfolgter Modifikation wurde die Ausgleichsfeuchte der Proben um 10 % bis 40 % reduziert. Die Abnahme der Ausgleichsfeuchte stabilisierte sich im Temperaturbereich von 200 °C bis 220 °C. Die Bruchschlagarbeit des unbehandelten Bambus betrug 3,8 J/cm², die des behandelten nur 1,4 J/cm². Die Bruchschlagarbeit variierte unabhängig von der Modifikation zwischen dem inneren und äußeren Abschnittes innerhalb des Halmquerschnitts. Der Eindruckswiderstand nahm mit der thermischen Behandlung ebenfalls ab. Unbehandelte Proben hatten 47 N/mm², während die modifizierten Proben nur noch 20 N/mm² aufwiesen. Anhand der Ergebnisse und erworbenen Erfahrungen lies sich schlussfolgern, dass Temperaturen zwischen 180 °C und 200 °C bei einer Haltezeit von drei Stunden für die thermische Modifizierung von Äthiopischem Hochlandbambus in Bezug auf die Entwicklung von ”woven strand boards” empfehlenswert waren.
27

Phylogeography and conservation genetics of waders

Rönkä, N. (Nelli) 29 March 2016 (has links)
Abstract Many waders are in decline, and the number of endangered species and populations is increasing. Their protection and management requires knowledge of both ecological and genetic state of the populations. In this thesis, I studied the distribution-wide genetic variation, structure and phylogeography of the Temminck’s Stint (Calidris temminckii) and Terek Sandpiper (Xenus cinereus) using microsatellites and sequence data from the mitochondrial control region and cytochrome oxidase I gene. I compared these regionally endangered species to other waders with varying evolutionary histories, breeding systems and habitat preferences to examine the levels of genetic variation and structure at different spatial scales. In addition, I studied the genetic structure of the endangered Baltic population of the Southern Dunlin (Calidris alpina schinzii) with microsatellites. I used genetic information in all three study species to determine units for conservation. The Temminck’s Stint and Terek Sandpiper, both not restricted to the Arctic, had low distribution-wide structuring. They also had quite low levels of variation when compared to other species breeding at similar latitudes, indicating reductions in population sizes during past climate changes. Especially the peripheral breeding populations were differentiated and showed signs of inbreeding and genetic drift when compared to the main range. The Temminck’s Stint populations at the Bothnian Bay and Yakutia, and Terek Sandpiper populations in Finland and Belarus, should be treated as separate management units. The broader interspecific comparison of waders suggests that habitat availability, mating system and the extent of philopatry may affect the genetic composition of species. The genetic analyses of the Southern Dunlin indicated strong effects of philopatry and inbreeding throughout the range. Local subpopulations at the Bothnian Bay and in Sweden need to be considered as separate management units. Management efforts at the Baltic should be focused on increasing connectivity and providing large enough breeding habitats for potential immigrants and recruits. / Tiivistelmä Useat kahlaajapopulaatiot ovat pienentyneet ja uhanalaistuneet maailmanlaajuisesti. Lajien ja populaatioiden ekologiaa ja genetiikkaa on tunnettava, jotta suojelutoimia voidaan kohdistaa oikein. Tutkin väitöskirjassani lapinsirrin (Calidris temminckii) ja rantakurvin (Xenus cinereus) geneettistä rakennetta, muuntelua ja fylogeografiaa levinneisyysalueen laajuisesti mikrosatelliittien ja mitokondrion kontrollialueen ja sytokromioksidaasi I -geenin sekvenssien avulla. Tutkin, mitkä tekijät vaikuttavat geneettisen rakenteeseen ja muunteluun vertaamalla näitä lajeja muihin kahlaajiin, joilla on erilaisia lisääntymisstrategioita, jotka pesivät vaihtelevissa ympäristöissä ja joista monet eroavat toisistaan myös fylogeografialtaan. Lisäksi tutkin Itämeren rannalla pesivän etelänsuosirrin (Calidris alpina schinzii) geneettistä populaatiorakennetta mikrosatelliittien avulla. Käytin geneettistä tietoa hyväksi luonnonsuojeluyksikköjen määrittämisessä kaikille kolmelle tutkimuslajilleni. Lapinsirrin ja rantakurvin fylogeografinen historia oli samankaltainen. Geneettisen muuntelun määrä oli vähäisempää verrattuna muihin, samankaltaisissa ympäristöissä pesiviin kahlaajiin. Molemmat lajit ovat todennäköisesti kärsineet historiallisten ilmaston-muutosten aiheuttamasta populaatioiden pienenemisestä. Erityisesti levinneisyysalueen reunoilla pesivät populaatiot olivat erilaistuneita, ja niissä näkyi sukusiitoksen ja geneettisen satunnaisajautumisen merkkejä. Perämeren ja Jakutian lapinsirri- sekä Valko-Venäjän ja Suomen rantakurvipopulaatioita tulee kohdella erillisinä suojeluyksiköinään. Vertailu muihin kahlaajiin osoitti, että niin pesimä- ja talvehtimisalueiden laajuus kuin lisääntymisstrategiat ja paikkauskollisuus voivat vaikuttaa lajien geneettiseen koostumukseen. Etelänsuosirrin geneettiset analyysit paljastivat merkkejä sukusiitoksesta, joita paikkauskollisuus ja populaatioiden pienuus ovat voimistaneet. Perämeren ja Ruotsin populaatioita tulee kohdella erillisinä suojeluyksiköinään. Suojelutoimet on kohdistettava tarpeeksi suurien, hyvälaatuisten pesimäpaikkaverkostojen ylläpitämiseen.
28

Designing Sustainable Alpine Skis : Combining user needs with ecological, social, and economical sustainablility

Barreflod, Tom-Oskar, Nilsson, Matilda January 2020 (has links)
As alpine skiing is becoming more and more popular the need for sustainable products are increasing in order to enable great skiing and snowy winters in the future. The ski industry is unfortunately far behind many other industries when it comes to sustainability and the shift towards sustainable skis is going slow. Norse Skis is a unique ski manufacturer as they have a sustainable profile and are always in the lookout for new possibilities to take that forward. The goal in this master thesis project is to develop a pair of sustainable skis that will widen Norse Skis’ product catalog. The project was conducted in collaboration with Norse Skis as a master thesis project within the degree of Industrial Design Engineering at Luleå University of Technology. During the development of the skis, the user-centered design process Design Thinking Process was used. The process was divided into three phases; Inspiration, Ideation, and Implementation. During the design process, most of the energy was put on creating a ski that meets the user needs and is as sustainable as possible. Through constant dialog with the users, feedback and evaluation were gained to customize the product to the needs and opinions of the users. To develop skis that are as sustainable as possible, the project has had its base in the three aspects of sustainability; ecological, economic, and social, which are defined in the Brundtland report (World Commission on Environment and Development, 1987).  At the beginning of the project, a deep understanding of alpine skis and alpine skiing was gathered. This was followed by a thorough examination of the users through surveys and user observations. It was identified that the users spent most of their time skiing on the piste, but had a vision of being an off-piste skier. This led to the conclusion of designing a ski that is high performing on-piste but also gives the user the possibility to great off-piste skiing. In a benchmarking, Norse Skis’ current skis were compared to their competitors’ to identify Norse Skis’ strengths and what could be improved. When an understanding of the product and the users was gained, the project proceeded into the ideation phase. In the ideation phase solutions on lengths, shapes, names, colors, graphics, and materials were created. Through user surveys, three concepts were created which eventually resulted in one final design. The project result is a pair of 90 mm wide skis with focus on sustainability that are high performing and playful in the piste while providing a nice off-piste ride as well. From the social aspect, they are created with the skier in mind instead of either men, women, or some specific age group. By using materials that are more environmentally friendly than what is used in Norse Skis’ skis today and that either have the same or lower price, the skis are more sustainable from both an ecologic and economic perspective. The design has been approved by the users which led to the recommendation of broadening Norse Skis’ current product catalog with the ski that was the result of this master thesis project. / Samtidigt som skidåkning blir mer och mer populärt för var dag som går så ökar behovet av hållbara produkter som möjliggör framtida snöiga vintrar och bra skidåkning. Tyvärr ligger dagens skidtillverkare långt bakom många andra branscher när det kommer till hållbarhet och skiftet mot hållbara skidor går trögt. Norse Skis är en unik skidtillverkare då de har en hållbar profil och ständigt letar efter möjligheter att komma ännu längre fram i utvecklingen. Målet i detta examensarbete är att utveckla ett par hållbara skidor som kan bredda Norse Skis produktkatalog. Projektet utfördes i samarbete med Norse Skis som ett examensarbete på Civilingenjör Teknisk Design med inriktning produktdesign vid Luleå Tekniska Universitet. Under utvecklingen av skidorna användes den användarcentrerade designprocessen Design Thinking Process som är uppdelad i tre faser; Inspiration, Ideation, och Implementation. Under designprocessen låg fokus på att skapa en skida som uppfyller användarbehoven och samtidigt är så hållbar som möjligt. Genom att hela tiden återkoppla med användarna för utvärdering och feedback kunde produkten anpassas efter deras behov och tycke. För att utveckla en så hållbara skida som möjligt har projektet utgått från de tre perspektiven av hållbarhet; ekologisk, ekonomisk, och social som identifieras i Brundtlandsrapporten (World Commission on Environment and Development, 1987).  I projektets startskede införskaffades en djup förståelse alpina skidor och alpin skidåkning. Detta följdes av djupdykning i användaren genom enkäter och användarobservationer. Det identifierades att användaren spenderar mest tid i pisten, men har en vision om att vara en off-pist åkare. Detta ledde fram till slutsatsen att designa en skida som är högpresterande i pisten med också ger användaren möjlighet till bra off-pist åkning. I en benchmarking jämfördes sedan Norse Skis nuvarande skidor med konkurrenternas för att identifiera Norse Skis styrkor och vad som kunde göras bättre. När en förståelse över produkten och användarna skapats gick projektet in i idégeneringsfasen. Där skapade olika lösningsförslag på längder, former, namn, färg, grafik, och material. Genom användarundersökningar kunde tre slutkoncept tas fram som slutligen resulterade i ett slutgiligt resultat. Projektresultatet är ett par 90 mm breda skidor med fokus på hållbarhet som är högpresterande och lekfulla i pisten som även ger en härlig åkning utanför. Ur den sociala aspekten är de gjorda för skidåkare istället för enbart män, kvinnor eller någon specifik åldersgrupp. Genom användning av material som är miljövänligare än de som Norse Skis tidigare använt och antingen har samma eller lägre pris så är skidor både hållbarare ur både ett ekologisk och ett ekonomiskt perspektiv. Designen har bekräftats av användarna vilket ledde till att rekommendationen att bredda Norses Skis produktkatalog med skidorna som var resultatet av detta examensarbete.
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Dynamics of streamflow and stream chemistry in a Swiss pre-Alpine headwater catchment : A fine scale investigation of flow occurrence and electrical conductivity in the temporary streams in the lower Studibach catchment / Dynamiken hos bäckflöden och bäckkemi i ett Schweiziskt pre-Alpint avrinningsområde av första ordningen : En finskalig undersökning av förekomsten av vattenflöde och elektrisk konduktivitet i temporära bäckar i den nedre delen av avrinningsområdet Studibach

Baumann, Elise, Berglund, Hanna January 2021 (has links)
Temporary streams and their dynamics have often been largely overseen in hydrological research and there is relatively little knowledge about how the occurrence of flow in these streams varies temporally and spatially. Temporary streams are important from a hydro- logical perspective because they affect water quantity and quality in downstream peren- nial reaches, and from an ecological perspective because they provide habitat to unique species. In order to gain knowledge about these important streams, this maser thesis was conducted, within the Msc program in Water and Environmental Engineering at Uppsala University and the Swedish University of Agricultural Sciences, in collaboration with the Hydrology and Climate group at the University of Zurich. In this study, the temporal and spatial variation of the temporary streams in a small pre-Alpine catchment in Switzerland were investigated, both in terms of the presence of flowing water and stream chemistry. The 20 ha Studibach catchment is typical for the pre-Alpine area, with frequent precipi- tation. The streams in the lower part of the Studibach catchment were mapped in the field during September 2020. The temporal and spatial variations of the presence of flow and stream chemistry within the stream network was investigated in September and October 2020 during varying weather conditions. During ten field campaigns the flow state of the streams was classified and the Electrical Conductivity (EC) of the streams was mea- sured approximately every 20 meter. The findings from the field campaigns were related to topographic indices, in particular the Topographic Wetness Index (TWI) and Upslope Accumulated Area (A), in order to see how topography influenced the presence of stream- flow and stream EC. The results show a high temporal and spatial variation in both stream chemistry and streamflow. The active network length expanded by a factor of two in re- sponse to precipitation events. The stream EC also had a large spatial variation, and the streams in the southeast part of the catchment had a higher EC than the other streams. This spatial variation is expected to reflect the large variability in groundwater EC within the catchment. The spatial variation of the streamflow demonstrated a difference between the north-middle and the south part of the catchment, where the south part responded quicker to events and drained and retracted faster after the event. The findings also indicate that topographic indices can predict the occurrence of flow in the stream network, with sites with higher topographic index values having a higher probability of flowing water in the stream. Topography also influences the stream chemistry. The variation in stream chem- istry was smaller for sites with higher values for the topographic indices, something that can be explained by the Representative Elementary Area (REA) concept, because sites with higher topographic index values are located further downstream and water at these locations is a mixture of the smaller streams that feed these streams. / Temporära bäckar och dess dynamik har länge varit förbisedda inom hydrologisk forskn- ing, och en djupgående kunskap rörande temporära och rumsliga variationer saknas. Tem- porära bäckar är viktiga utifrån ett hydrologisk perspektiv eftersom de påverkar både kvantitet och kvalitet på vattnet nedströms, och från ett ekologiskt perspektiv eftersom de bidrar med habitat till unika arter. Detta examensarbete har genomförts för att öka kunskapen kring dynamiken i dessa temporära nätverk. Examensarbetet genomfördes inom Civilingenjörsprogrammet i Miljö och Vattenteknik vid Uppsala Universitet och Sveriges Lantbruksuniversitet, i ett samarbete med Hydrologi- och Klimatgruppen vid University of Zurich. Studien har undersökt temporära och rumsliga variationer i ett tem- porärt bäcknätverk med avseende på flöden och kemin i vattnet, i ett mindre pre-alpint avrinningsområde i centrala Schweiz. Bäckarna i den nedre delen av avrinningsområdet Studibach karterades i fält för hand med karta och kompass under september 2020. Avrin- ningsområdet är på 20 ha och räknas som typiskt för ett pre-Alpint område, med frekvent nederbörd. Tio fältkampanjer genomfördes där temporära och rumsliga variationer un- dersöktes genom klassificering av flöden och mätningar av Elektrisk Konduktivitet (EC) i bäckarna ungefär var 20e meter, under september och oktober 2020 i varierande väder- förhållanden. Resultaten från fältkampanjerna relaterades till de topografiska indexen Topographic Wetness Index (TWI) och Upslope Accumulated Area (A) för att undersöka hur topografin påverkar flöden och bäckkemin. Studien kom fram till att bäckarna i den nedre delen av Studibach visar både en temporär och en rumslig variation för både flöde och bäckkemi. De aktiva bäckarna i nätverket visade på en expansion med en faktor två som svar på nederbörd. En rumslig variation för flödet påträffades även mellan den södra och nord-centrala delen av nätverket där den södra svarade snabbare mot event och även drogs ihop snabbare. Kemin i bäckvattnet visade på en stor rumslig variation, med högt EC i den sydöstra delen av avrinningsområdet, vilket förmodas bero på den stora rumsliga variationen av EC i grundvattnet. Resultaten visar även på att topografiska index kan till viss del förutspå flöden i bäckarna, där platser med högre topografiska index har högre sannolikhet att det flödar i bäcken. Topografin påverkar även bäckkemin. Variationen i bäckkemin var mindre för platser med högre topografiska index, vilket kan förklaras med Representative Elementary Area (REA) konceptet, eftersom platser med högre to- pogragiska index värden återfinns längre nedströms och vattnet på dessa platser är en blandning av de mindre bäckarna som tillför vattnet till de större.
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Ritmos de actividad motora, comportamiento alimentario e influencia de la melatonina exógena en peces teleósteos

Herrero Ramón, María Jesús 26 October 2007 (has links)
La presente Tesis Doctoral tiene como objetivo profundizar en los conocimientos sobre ritmos biológicos y comportamiento alimentario de tres especies de peces teleósteos de interés en acuicultura: tenca (Tinca tinca), trucha alpina (Salvelinus alpinus) y lubina (Dicentrarchus labrax).Con este fin se ha investigado la influencia de factores bióticos y abióticos en la sincronización de los ritmos de actividad locomotora y alimentaria, así como el carácter endógeno y/o exógeno de estos ritmos. A su vez, se ha profundizado en el comportamiento individual de truchas alpinas mantenidas en grupo, mediante una nueva metodología que permite estudiar los ritmos de demanda voluntaria de alimento y la autoselección dietaria de los individuos. Asimismo, se ha analizado la influencia de los niveles endógenos de melatonina, modificados mediante la administración de melatonina exógena y de su aminoácido precursor (triptófano) en la dieta, sobre la concentración de cortisol y el ritmo de actividad locomotora en lubina. / This Doctoral Thesis deeps into the knowledge about biological rhythms and feeding behaviour in three teleostean fish species of interest in aquaculture: tench (Tinca tinca), Arctic charr (Salvelinus alpinus) and European sea bass (Dicentrarchus labrax). With this aim, the influence of biotic and abiotic factors has been researched in the field of synchronization of locomotor and feeding rhythms, as far as the endogenous or exogenous character of these rhythms. Moreover, individual feeding behaviour of Arctic charr kept in groups has been studied trying a new methodology which allows the monitoring of feeding demands and dietary self-selection of individuals. Furthermore, influence of endogenous melatonin modified through exogenous melatonin and its precursor amino acid (tryptophan) administration in the diet, in the cortisol levels and locomotor activity rhythms in sea bass were analysed.

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