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Uncovering and understanding the processes that have led to the biological diversity we observe today are of fundamental interest in biology. Since direct observation of speciation is usually impossible, knowledge about the processes behind species formation can be gathered by studying mutations, natural/sexual selection, and genetic drift. In this thesis I aim to identify evolutionary processes that cause species divergence and, ultimately, speciation using Swedish cyprinid fish as a model system. Assuming that the demographic history of a population is mirrored in the genome, I studied the effects of a bottleneck on genetic variability in populations of roach. As expected, I found that a decrease in population size caused a decrease in genetic variability, a pattern that was obtained from both microsatellite and mitochondrial data. The importance of hybridization for speciation is debated, however, by analyzing morphology and microsatellites I could show that common bream and white bream and their interspecific hybrids are phenotypically and genetically differentiated and that ongoing geneflow is mainly unidirectional. Ongoing geneflow antagonizes the effect of genetic drift, but by studying isolated populations (= no gene flow) the impact of genetic drift can be assessed. Long-term isolated populations of roach and perch surprisingly showed stable levels of genetic diversity over time despite decreasing effective population size. However, each population genetically diverged during the period of investigation, a finding that is consistent with the effect of drift. An analysis of the systematic relationship of the 18 species of Swedish cyprinids revealed low congruence of phylogenies based on two different genetic markers. The position of the tench remains unresolved and the relationship of common bream and white bream as sister species cannot be confirmed. Within cyprinid fishes, diversification rates reveal a slowdown with time, a pattern that I found also in other fish clades and that is consistent with density-dependent cladogenesis. Overall, based on the findings presented in this thesis I emphasize that the maintenance of genetic variation in populations is essential since genetic variation is the key element for processes of divergence to act upon.

The population size of the horned grebe, Podiceps auritus, is declining in most of the world due to loss of wetlands, deteriorating water quality and establishment of predatory fish such as pike, Esox lucius, in former fish free wetlands. The horned grebe is now globally classified as vulnerable. In this study, data on population dynamics of the horned grebe in six created wetlands in Linköpings kommun was examined together with field work carried out in three of the wetlands. The results indicate that the number of pairs and juveniles of horned grebe crash six to eight years after the wetland is created and does not recover if there is fish present. The pairs and juveniles of horned grebe decreased significantly with the increasing age of the wetland if there was pike present in the wetland. Reduction fishing and drainage of the water in two of the wetlands inhabited pike showed a small improvement in population size of the horned grebe, but the numbers ultimately declined after a few years. Reduction fishing of common roach in one wetland showed a continuing improvement in the population size of horned grebe. Other factors that affected the horned grebe negatively, was an abundance of macrophytes such as Canadian pondweed, Elodea canadensis, that makes foraging harder.

This thesis is an interdisciplinary analysis of jazz music and poetry produced by African-American artists, primarily in New York, over the course of the 1960s, set within the broad context of the civil-rights and black-nationalist movements of the same period. Its principal contention is that the two forms afford each other symbiotic illumination. Close reading of jazz musicology in particular illuminates the directions taken by the literature of the period in a manner that has rarely been fully explored. By giving equal critical attention to the two artistic forms in relation to each other, the epistemological and social radicalism latent and explicit within them can more fully be understood. Through this understanding comes also a greater appreciation of the effects that the art of this period had upon the politics of civil rights and black nationalism in America - effects which permeated wider culture during a decade in which significant change was made to the legal position of African-Americans within the United States, change forced by a newly, and multiply, vocalized African-American consciousness. The thesis examines the methods by which jazz and literature contributed to the construction of new historically-constituted black subjectivities represented aurally, orally and visually. It looks at how the different techniques of each form converse with each other, and how they prompt consequential re-presentations and re cognizations of established forms from within and without their own continua. That examination is conducted primarily through forensic close readings of records made between 1960 and 1967, which though of widely differing styles nevertheless can be said to fall under the broad umbrella term of 'post-bop' jazz, alongside equally close readings of poetry written primarily by members of the New York wing of the equally broadly-termed Black Arts Movement [BAM] between 1964 and 1969.

In der Studie wurde die Ernährung und die Verteilung von larvalen und juvenilen Stadien von Plötze (Rutilus rutilus (L.)) und Barsch (Perca fluviatilis L.) untersucht. Untersuchungsgewässer war der Feldberger Haussee, ein geschichteter eutropher Hardwassersee, der seit über 15 Jahren biomanipuliert wurde. Der Bestand an Barschen war in diesem Gewässer im gesamten Biomanipulationszeitraum sehr gering (< 1% der Gesamtfischbiomasse). Längerfristig stabilisiert, aus wissenschafticher Sicht, eine hoher Bestand an piscivoren Barschen die Effekte der Biomanipulation. Ziel der Untersuchung war daher die Überprüfung der Hypothese, dass das Vorhandensein von Konkurrenz um die Ressource Zooplankton zwischen den juvenilen Barsch und Plötzen für den geringen Barschbestand verantwortlich ist (PERSSON & GREENBERG 1990, PERSSON et al. 1991). Die Ergebnisse der Untersuchungen ließen sich in folgenden Punkten zusammenfassen: i) Der juvenile Barsch segregierte in der Hochsommer- bis Herbstperiode in eine spezielle Nahrungsnische. Die beiden Fischarten unterschieden sich deutlich bezogen auf die Art der bevorzugten Zooplankter (0+-Barsch vorwiegend Eudiaptomus, Diaphanosoma, Leptodora; 1+/2+-Plötzen fraßen Cladocerennahrung Bosmina und in hohen Anteilen auch Daphnia). Separation und Aufteilung der Zooplanktonresourcen konnte auch für die bevorzugte Größe der Zooplankter beobachtet werden. Die hohen Wachstumsraten und der gute Konditionszustand des juvenilen Barsches sowie das Fehlen von Wintermortalität ließen konkurrenzinduzierte Mortalität als Begründung für den geringen Bestand nicht glaubhaft erscheinen. ii) Die räuberbedingte saisonale Mortalität der juvenilen Barsche in der Hochsommer- bis Herbstperiode ließ sich bei den 0+-Barschen und 1+-Barschen jeweils auf bis zu 90% einschätzen. Dadurch wurde auch ein starker Jahrgang (wie 1997) innerhalb der ersten zwei Lebensjahre auf bis zu 99% reduziert. iii) Als Alternativhypothese wurde aus den Ergebnissen der Studie und den Bedingungen am Feldberger Haussee gefolgert, dass eine Kombination von langer zooplanktivorer Phase und einem hohen Bestand an effektiven pelagischen Piscivoren (wie Sander lucioperca L.) für den geringen Barschbestand verantwortlich ist. / In the study the feeding behaviour and distribution of larval and juvenile stages of roach (Rutilus rutilus (L.)) and perch (Perca fluviatilis L.) was examined. The object of the study was the Lake Haussee, an stratified eutrophic hardwater lake that was biomanipulated for more than fifteen years. Over the whole period of biomanipulation the portion of perch population did not reach the level of one percent of the total fish biomass. From the scientific point of the view, a high biomass of piscivorous perch may stabilize the effects of biomanipulation in the long run. The aim of the study was to evaluate the hypothesis of strong competitive interaction between juvenile roach and perch for zooplankton, which could be responsible for the minor population of perch in lakes (PERSSON & GREENBERG 1990, PERSSON et al. 1991). The results of the study can be summarised as follows: i) In the period of midsummer to autumn juvenile perch segregated to a special food niche. In comparison to 1+/2+-roach, which fed on cladocerans (e.g. Bosmina and a high portion of Daphnia), 0+-perch preferred Eudiaptomus, Diaphanosoma and Leptodora. Thus, partitioning and separation were also observed for size-selectivity. Furthermore, the high growth rates and the good state of condition of the young perch as well as the lack of winter mortality did not indicate a competitive-induced mortality in the Lake Haussee. ii) In the period of midsummer to autumn the predator-induced seasonal mortality of juvenile perch (groups like 0+/1+) was estimated nearly up to 90 percent. Thereby, also a strong age group (like 1997) of juvenile perch was reduced up to 99 percent within the first two years of life. iii) The results of this study supported an alternative hypothesis: the morphological conditions of Lake Haussee, a prolonged zooplanktivore period of juvenile perch in combination with a strong stock of an effective pelagic piscivore predator (like Sander lucioperca L.) are responsible for the low perch stock.

L’objectif de ce travail de thèse est d’évaluer le degré de contamination des différents compartiments du site de la décharge d’Étueffont à savoir : les lixiviats, les sédiments, l’eau souterraine, les poissons, les insectes et les microorganismes de la décharge d’Étueffont. Ce travail de recherche est structuré en neuf chapitres.Après une première partie (Part I) consacrée à une étude bibliographique, le deuxième chapitre (Part II) présente le site d’étude, c’est-à-dire l’installation de stockage de déchets non dangereux(ISDND) d’Étueffont. La troisième partie (Part III) est consacrée à l’analyse de la qualité des lixiviats dans les lagunes, les unités de stockage des déchets « Nouveau casier », « Sous casier », « Ancienne décharge », les ruisseaux du gros Pré et Mont Bonnet. La quatrième partie (Part IV) intitulée « Contamination métallique des sédiments du site de la décharge d’Étueffont », aborde l’étude de la variation spatiotemporelle des éléments traces métalliques au niveau des lixiviats et des sédiments dans les quatre lagunes du site de la décharge d’Étueffont. Afin de déterminer le degré de contamination métallique des lixiviats et des sédiments, nous avons procédé à un suivi de certains éléments localisés en amont, au milieu et en aval de chaque lagune avec un pas d’échantillonnage trimestriel entre octobre 2013 et avril 2016. La cinquième partie (Part V), complémentaire du chapitre précédent, définit plus précisément la distribution spatiale du panache à travers l’analyse de la qualité de l’eau souterraine au moyen de piézomètres. La sixième partie (Part VI) concerne les effets des métaux lourds sur les échanges gazeux et la fluorescence des chlorophylles chez (Typha latifolia). Le septième chapitre (Part VII) est consacré à l’étude des microorganismes de la décharge d’Etueffont : apport de la cytométrie en flux. Dans le huitième chapitre (Part VIII), nous aborderons l’étude de la bioaccumulation des éléments traces métalliques dans le Chironome Chironomus riparius. La dernière partie (Part IX) intitulée « Étude de la bioaccumulation des éléments traces métalliques au niveau des différents organes du gardon Rutilus rutilus», aborde l’étude de la bioaccumulation des éléments traces métalliques au niveau de différents organes (muscle, foie, arêtes et branchies). / The objective of this thesis work is to estimate the contamination level in the various compartments of the Étueffont discharge site namely: leachates, sediments, groundwater, fishes and insects. The microorganisms (< 10 µm) of the Étueffont discharge of were investigated at the single cell level by flow cytometry. This research work is structured in nine chapters.The first part (Part I), is dedicated to a literature review. Part II presents the study site, the storage of non-hazardous waste (ISDND) at Étueffont. Part III is dedicated to the analysis of leachate quality in lagoons, NC, SC, AD, MB and GP. Part IV addresses "Metal Sediment Contamination of Étueffont discharge site" It concerns the study of spatial and temporal variation of trace metals in leachate and sediment in the four lagoons landfill site of Étueffont. To determine the metal contamination level in leachate and sediment, we conducted follow-elements located upstream, middle and downstream in each lagoon with quarterly sampling between October 2013 and April 2016. Part V complements the previous chapter, by specifically defining the spatial distribution of the plume through the quality analysis of the piezometer groundwater. Part VI addresses the heavy metals impacts on gas exchange and chlorophyll fluorescence in (Typha latifolia). Part VII is dedicated to the microorganisms (<10 µm) investigation in the Étueffont discharge: by using flow cytometry. In the (Part VIII), we addressed the study of bioaccumulation of trace metallic elements (Cr, Mn, Co, Ni, Cu, Zn, As, Mo, Cd and Pb) in insect Chironomus riparius. Part IX entitled "Study bioaccumulation of trace metals in the various organs of roach Rutilus rutilus" concerns bioaccumulation of trace metals in different organs (muscle, liver, bones and gills) of this fish.

Migration occurs among many animal species for the purpose of, among other things, finding food or to reproduce. Spawning migration is a form of migration that occurs among many fish species where they move to another site for reproduction. The movement can be obstructed by migration barriers like road culverts. Barriers to migration pose one of the greatest threats to biodiversity and ecosystem functions in freshwater. They impair the connectivity of watercourses and may prevent fish from improving reproductive success or completing their life histories altogether. There are both benefits and costs with migration, benefits such as increased survival for the adults and offspring, and costs such as increased energy consumption and increased mortality. The costs are often dependent on the morphological traits of the individual, like body shape and size. In this study, the spawning migration of two species of fish of the family Cyprinidae, ide (Leuciscus idus) and roach (Rutilus rutilus) was investigated. Few studies have been made on ide or on roach compared to other cyprinids and salmonids. This study might therefore enhance the overall knowledge of these two species. The overall aims of this project are to study and compare phenotypic correlates of spawning migration behaviour of ide and roach. The field studies were performed in Oknebäcken, Mönsterås (SE632310-152985), Sweden in March and April 2020. To describe the watercourse and define the location and characteristics of different potential migration barriers, a simplified biotope mapping method was used. The fish were caught in a hoop net and then measured, weighted, sexed, and injected with passive integrated transponder using the bevel down method. In order to register in stream movement of fish, reading stations with antennas were placed, at two locations upstream from the marking station and one downstream at the estuary. The sex ratio differed from the expected 1:1 with a majority of females for both species. This might be a result of fluctuations in survival of spawn coupled with different age-at-maturity between sexes. We found that individuals that arrived early to the stream were larger for both study species, as other studies also reported. Also, male ide was both larger and arrived before female ide. There might be an energy cost associated with early arrival to the stream and therefore, larger individuals arrive first. For roach, there was no difference in arrival time between the sexes although female roach were larger. There was no difference in the time spent in the stream between the species. For ide, females stayed for a longer period of time in the stream than males. However, the opposite was true for roach. This may be because male roach might benefit from more fertilization events when staying longer. There might therefore be a trade-off between the energy cost in staying in the stream and the increased fitness advantage in fertilization events. We found no correlation between any of the morphological traits and migration distance. However, since very few individuals were registered at the upstream reading stations, there might be an effect of migration barriers on the spawning migration. The mortality after spawning was higher for roach than for ide. For ide, a larger proportion of females than males died. For roach, individuals that arrived early was classified as alive to a greater extent than those who arrived late. Both similarities and differences between the species were discovered in this study which concludes that even closely related species might differ substantially from each other.

Phased array feeds (PAFs) are a promising new technology for astronomical radio telescopes. While PAFs have been used in other fields, the demanding sensitivity and calibration requirements in astronomy present unique new challenges. This dissertation presents some of the first astronomical PAF results demonstrating the lowest noise temperature and highest sensitivity at the time (66 Kelvin and 3.3 m^2/K, respectively), obtained using a narrowband (425 kHz bandwidth) prototype array of 19 linear co-polarized L-band dipoles mounted at the focus of the Green Bank 20 Meter Telescope at the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia. Results include spectral line detection of hydroxyl (OH) sources W49N and W3OH, and some of the first radio camera images made using a PAF, including an image of the Cygnus X region. A novel array Y-factor technique for measuring the isotropic noise response of the array is shown along with experimental measurements for this PAF. Statistically optimal beamformers (Maximum SNR and MVDR) are used throughout the work. Radio-frequency interference (RFI) mitigation is demonstrated experimentally using spatial cancelation with the PAF. Improved RFI mitigation is achieved in the challenging cases of low interference-to-noise ratio (INR) and moving interference by combining subspace projection (SP) beamforming with a polynomial model to track a rank 1 subspace. Limiting factors in SP are investigated including sample estimation error, subspace smearing, noise bias, and spectral scooping; each of these factors is overcome with the polynomial model and prewhitening. Numerical optimization leads to the polynomial subspace projection (PSP) method, and least-squares fitting to the series of dominant eigenvectors over a series of short term integrations (STIs) leads to the eigenvector polynomial subspace projection (EPSP) method. Expressions for the gradient, Hessian, and Jacobian are given for use in numerical optimization. Results are given for simulated and experimental data, demonstrating deeper beampattern nulls by 6 to 30dB. To increase the system bandwidth toward the hundreds of MHz bandwidth required by astronomers for a fully science-ready instrument, an FPGA digital backend is introduced using a 64-input analog-to-digital converter running at 50 Msamp/sec and the ROACH processing board developed at the University of California, Berkeley. International efforts to develop digital back ends for large antenna arrays are considered, and a road map is proposed for development of a hardware correlator/beamformer at BYU using three ROACH boards communicating over 10 gigabit Ethernet.

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The populations of three–spined sticklebacks (Gasterosteus aculeatus) in the Baltic Sea have increased tenfold over the last decade. A large increase in abundance can alter the offshore and coastal food webs. Despite of these facts, there are large gaps in the knowledge about the stickleback ecology in the Baltic and the possible effect they might have on their environment. Earlier investigations state that stickleback mainly occupy the deeper areas offshore, and only migrate to the shallow areas during May–July to spawn. Observations by recreational fishermen indicate that this may be incorrect, and that some adult sticklebacks are present in the shallow areas even during the winter. One aim of this study was to investigate the timing of stickleback migration to a shallow coastal area in Kalmar Sound. The study also aimed to examine the relative abundance in two adjacent shallow areas in the archipelago south of Kalmar, where one of the areas is a pike spawning ground. A one month long test fishing with fyke nets was started on the first day after ice break. Results show that the sticklebacks are present in the bays immediately after the ice break, and that high abundances coincide with the pike spawning period. Stomach analyses showed that sticklebacks consumed a large proportion of crustaceans, but also fish eggs were found. These results shed new light on the management actions for many of the coastal spring spawning fish species that have shown decreasing abundances during the last decades. / Bestånden av storspigg (Gasterosteus aculeatus) i Östersjön har ökat markant, data visar på en tiofaldig ökning under det senaste decenniet. Ökningen kan medföra att bl.a. näringsväven, till havs och längs kusterna förändras. Trots vetskapen om detta finns det kunskapsluckor kring spiggens ekologi och dess möjliga påverkan på sin omgivning. Litteratur säger att spiggen till största del bara befinner sig inne längs kusterna under maj-juli. Observationer från sportfiskare tyder på att detta inte stämmer, och att vuxen storspigg befinner sig inne längs kusten och i skärgårdsvikar året om. Ett syfte med studien var att undersöka när spiggen kom in till de grunda vikarna i Kalmarsund. Studien jämförde även spiggtätheterna mellan två närliggande områden där den största skillnaden var födan. Ett månadslångt provfiske inleddes den första isfria dagen i två skyddade vikar söder om Kalmar, där en av lokalerna var en dokumenterad leklokal för gäddor. Resultaten visade att spiggen fanns i vikarna direkt efter islossningen, och vid fisket sammanföll de största spiggfångsterna med gäddleken. Maganalyser visade att en stor andel av födan bestod av olika kräftdjur, men även romkorn hittades. Resultaten tyder på andra förutsättningar för många av de hårt ansatta vårlekande fiskarterna än vad som tidigare är dokumenterat.