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This diploma thesis describes the design of winglets for LS-3 glider. The method for determination of main winglet parameters based on selected criterion is presented as well as comparation of performace of original wing and final modification. It also includes analysis of wing loading and resetting of speed and weight limits for flying with winglets.

Bats are important components of biodiversity within forested ecosystems. This research addressed habitat characteristics that influence species occupancy and stable isotopes and wing morphology to assess community structure within the Sam D. Hamilton Noxubee National Wildlife Refuge. To meet these objectives, I deployed echolocation recorders, mist-nets and conducted roost checks to capture bat acoustics; fur samples were also collected to measure ratios of carbon (C13/12) and nitrogen (N15/14). Relationships between occupancy, habitat class and features were not apparent for most species. However, Lasiurus and Mytois spp. showed positive relationships with proximity to roads, Lasiurus, positive with stem density and Perimyotis subflavus, negative with basal area. Stable isotope analysis revealed some distinction of trophic niches while wing morphometrics indicated bats of similar wing shape and size show greater trophic overlap. Collectively, these results suggest that habitat management, as current within the study area, will have limited influence on local bat distributions.

Selection pressure is a constant force in evolution, pushing birds and their wings towards an optimal shape and structure, were increasing performance, and minimizing the costs is central. But even though the science of aerodynamics can provide calculations of the optimal construction for the wing in different situations this rarely directly correspond to what is observed in nature. Since the optima are not the same for all birds due to different specifications and ecology this optimum becomes harder to determine and different functions can even have different optima, resulting in selection conflict. In the genius of birds there is an immense variation between species and their wings in everything from size, shape, and function.  The aim of this study is to investigate how wing morphology over a large phylogeny of bird species correlates to migration and habitat/ecology. Many studies have been done focusing on the effect of migration on the wing morphology, and some have been done focusing on other parameters such as display or daily usage. But by including the bird’s ecology and habitat related information with migration and morphology and looking at the selection from a broad perspective, can we uncover something more? The morphology of the wing cannot provide a perfect optimum for all circumstances since they require different specifications. What then, has the largest impact on the wing’s morphology? And does the relative length of the tail provide any correlations with its habitat and performance?  1185 birds of 137 species were caught at Ottenby, Öland and information on age, weight, sex, and tail length was collected for each individual bird. Photographs were taken of the back of the bird with the left wing outstretched 90 degrees from the body and analyzed in ImageJ to calculate aspect ratio and wing loading. Data on migration distance, foraging behavior, diet, and habitat density was then added for each of the species. Mean values of all parameters was calculated on species level creating a strong dataset with 137 data points. The species mean values dataset was used to test the interspecific effects and the dataset with all individuals was used to test intraspecific effects. ANOVAs, ANCOVAs, correlations tests and random slopes mixed models were performed revealing significant connections between wing morphology, migration, and habitat density. Correlations could also be observed between wing morphology, diet, and foraging behavior. Habitat density revealed the highest correlation with wing morphology, demonstrating a greater significance than migration and the other parameters. Effects that at first sight looked significant could later be excluded as they turned out to be dependent on other variables. The study therefore also highlights the importance of including alternative parameters for reliable conclusions.

L'introgression est un processus fréquent et qui a d'importantes conséquences évolutives. L'objectif de ce travail était de tester un modèle neutre d'introgression chez des épicéas du Plateau tibétain et des régions voisines. Le travail a permis de mettre en évidence que la direction de l'introgression pouvait être prédite par la dynamique passée des populations d'arbres, et que l'importance de cette introgression était inversement proportionnelle à l'intensité des échanges génétiques au sein de l'espèce invasive, grâce à la comparaison de la structure génétique basée sur des marqueurs chloroplastiques (à hérédité paternelle) et mitochondriaux (à hérédité maternelle). / Introgression is a widespread phenomenon with potentially profound evolutionaryconsequences. Recently, significant progress in our understanding of introgression hasbeen made with the development of a neutral model. This model predicts that, whenone species invades an area already occupied by a related species, introgression ofneutral genes takes place mainly from the local species towards the invading ones. Inaddition, following a contact between two hybridizing species, the model predicts thatintrogression should be particularly frequent for genome components experiencinglittle gene flow. However, to date, there was no empirical example available, in whichone species expanded into the range of a closely related one and two markers withcontrasted rates of gene flow had been studied for both species. Only in such a casecould the two predictions outlined above be tested simultaneously. In addition, basedon these two predictions, species delimitation should be more efficient when usingmolecular markers experiencing high rates of gene flow. The present thesis was designed to test the hypotheses of this model. The biologicalmodel used was conifers, a group in which introgression and hybridization arecommon because of incomplete reproductive isolation. The species investigatedbelong to the genus Picea (spruce). We focused on two species complexes,represented by monographic clades in a phylogenetic study using the chloroplast genematK. All species studied occur in the Qinghai-Tibetan Plateau (QTP) and adjacenthighlands. The phylogeography of these species complexes was reconstructed usingorganelle markers (mitochondrial DNA, mtDNA and chloroplast DNA, cpDNA). Inconifers, mtDNA and cpDNA have contrasted modes of inheritance. The former ismaternally inherited, transmitted by seeds experiencing little gene flow while thelatter is paternally inherited, transmitted by both pollen and seeds experiencing highlevels of gene flow. Therefore, uniparentally inherited mtDNA and cpDNA markersexperience different rates of gene flow in such a group, providing an ideal model to test the relationship between rates of gene flow, introgression and species delimitation.Two mtDNA fragments (nad1intron b/c; nad5 intron1) and three cpDNA fragments(ndhK-C；trnL-trnF；trnS-trnG) were sequenced for nine species belonging to thePicea asperata and P. likiangensis species complex.(1) Nine mtDNA and nine cpDNA haplotypes were detected in 459 individualsfrom 46 natural populations in five species of P. asperata complex. As found in mostconifer species studied so far, low variation is present in the two mtDNA intronsalong with a high level of differentiation among populations (GST = 0.90). In contrast,higher variation and lower differentiation among populations was found at cpDNAmarkers (GST = 0.56). The cpDNA, although far from being fully diagnostic, is morespecies-specific than mtDNA: four groups of populations were identified usingcpDNA markers, all of them related to species or groups of species, whereas formtDNA, geographical variation prevails over species differentiation. A literaturereview shows that mtDNA variants are often shared among related conifer species,whereas cpDNA variants are more species-specific. Hence, increased intraspecificgene flow appears to decrease differentiation within species but not among species.[...]

Drag polars for three Micro Air Vehicles (MAVs) were measured at Reynolds numbers of 70,000, 50,000, 30,000, and 10,000 and compared to predictions generated using the classical approach. The MAVs tested had different configurations and aspect ratios varying from 1.2 to 1.6 and ratios of wetted surface area to planform area from 2.6 to 3.9. A force balance was used to measure the lift and drag on the MAVs at angles of attack ranging from -5 degrees (or -10 degrees) to 10 degrees. The force balance allowed the MAVs to rotate in the pitching axis. The MAV angle of attack was set using an elevator installed on the MAV and controlled using a standard radio control used by RC plane enthusiasts. Uncertainty analysis performed on the data showed the uncertainty for high Reynolds numbers was dominated by velocity uncertainty, and uncertainty for the lower Reynolds numbers was dominated by uncertainty in the force measurements. Agreement between measured and predicted drag polars was good with the measured drag never being more than two times the predicted drag. For the majority of the tests, the drag coefficients followed the expected Reynolds number trend: increasing with decreasing Reynolds number.