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251	The Presence of Micropterus salmoides (Largemouth Bass) Influences the Populations of Rana draytonii (California Red-Legged Frog) and Pseudacris regilla (Pacific Treefrog) in Two Ponds in Santa Barbara County, California Gilliland, Kenneth Lee 01 February 2010 (has links) (PDF) Alien fish have been implicated in the decline of Rana draytonii (California red-legged frog) and Pseudacris regilla (Pacific treefrog) populations. Micropterus salmoides (largemouth bass) is a common sport fish that has been introduced into the sympatric range of these two anuran species; however, no studies have investigated the individual influence that this alien fish has on these two species. I conducted M. salmoides control or eradication experiments during a four year study in two ponds within the Transverse Mountain Range of Santa Barbara County, California. Changes in the densities of all life stages of R. draytonii and P. regilla were assessed through repeated visual encounter surveys. In response to the manipulations of the M. salmoides populations there was an increase in the density of both species. For R. draytonii, this salient increase in density was recorded in the larval and metamorph life stages. For P. regilla, a slight, yet steady increase in the density of adult, metamorph, and larval life stages was recorded. My results suggest that M. salmoides can be controlled or eradicated from lentic waterbodies and provides reasonable evidence that the negative effects of this species on R. draytonii and P. regilla populations can be minimized or reversed. The reversal of these effects may translate into increases in the densities and potential recruitment of these two native anurans. Therefore, my results provide tentative support that the control or eradication of M. salmoides where they cohabitate with these two species may be a viable conservation measure for R. draytonii and P. regilla populations. Since my study was performed at a very local scale and all results are strictly observational and descriptive, additional studies should be performed at a larger spatial scale and buttressed with controlled laboratory and field enclosures experiments to identify the causal factors responsible for the identified patterns. Rana draytonii California red-legged frog Pseudacris regilla Pacific treefrog Micropterus salmoides largemouth bass alien fish anuran declines Animal Sciences Biology Ecology and Evolutionary Biology Life Sciences Population Biology Terrestrial and Aquatic Ecology Zoology
252	Reproductive behaviour of the European Common Frog (Rana temporaria) Dittrich, Carolin 26 June 2020 (has links) In meiner Dissertation untersuche ich das Paarungs- und Fortpflanzungsverhalten des Europäischen Grasfrosches (Rana temporaria) in einem evolutionären Kontext. Mein Ziel ist es zu verstehen, welche Mechanismen zur Bildung von Paaren führen, ob die Partnerwahl die Paarungsmuster erklärt, die wir beobachten können, und ob es evolutive Vorteile gibt, die sich aus der Paarung mit einem bestimmten Partner ergeben. Die Suche nach und die Konkurrenz um Paarungspartner führt zur Entwicklung verschiedener Paarungssysteme, Strategien und Taktiken, um den Reproduktionserfolg während der gesamten Lebensdauer zu erhöhen. Das Paarungsverhalten wird durch natürliche und sexuelle Selektion beeinflusst, wobei beide in unterschiedliche Richtungen wirken können. Für die meisten Individuen ist das Überleben unerlässlich, um sich so oft wie möglich zu reproduzieren, und dadurch die reproduktive Gesamtfitness zu erhöhen. Andererseits könnte ein auffälliges Verhalten bei der Fortpflanzung das Prädationsrisiko erhöhen. Der Akt der Paarung selbst kann bereits mit Risiken verbunden sein, welche sich auf die Überlebensraten auswirken können. Durch sexuelle Selektion könnten bestimmte sekundäre Geschlechtsmerkmale begünstigt werden, entweder aufgrund von Vorteilen im Wettbewerb innerhalb eines Geschlechts (intrasexuell), oder aufgrund spezifischer Präferenzen zwischen den Geschlechtern (intersexuelle Selektion). Damit sich die Partnerwahl entwickeln kann, muss der gewählte Paarungspartner Vorteile aufweisen, von denen der wählende Partner profitiert, denn die Wahl ist mit energetischen Kosten und zeitlichem Aufwand verbunden. Als Frühlaicher muss der Europäische Grasfrosch mit einem eingeschränktem Paarungszeitraum umgehen. Die Männchen konkurrieren um den Zugang zu Weibchen und es wird angenommen, dass sich Weibchen während der Paarung und Reproduktion passiv verhalten, da der hohe "Männchen-Überschuss" keine Wahl zulassen würde. Aus evolutionärer Sicht sollten Weibchen jedoch das wählerische Geschlecht sein und entscheiden mit wem sie sich paaren, da sie mehr Energie in die Eierproduktion investieren. / In my thesis, I examine the mating and reproductive behaviour of the European Common Frog (Rana temporaria) in an evolutionary context. I aim to understand which mechanisms lead to the formation of pairs, if mate choice shapes the patterns of mating that we can observe and if there are benefits derived from pairing with a specific mate. The search and competition for mating partners lead to the evolution of various mating systems, strategies and tactics to increase lifetime reproductive success. The mating behaviour is influenced by natural and sexual selection, whereby both could act in different directions. For most individuals, survival is essential in order to reproduce as often as possible to increase lifetime reproductive fitness. On the other hand, reproduction could increase predation risk due to conspicuous behaviour and risks associated with mating itself. Sexual selection could favour specific secondary sexual traits, either due to advantages in intrasexual competition, or by specific preferences of the choosy sex (intersexual selection). For mate choice to evolve, there need to be benefits associated with the chosen mating partner, because choosiness involves costs in terms of energy and time constraints during mating. As an explosive breeder, the European Common Frog has to deal with time constraints during the short breeding season. The males are competing for the access to females and it is assumed that females are passive during breeding due to a high male-biased operational sex ratio. However, from an evolutionary perspective females should be the choosy sex and should decide with whom to mate, as they invest more energy into the production of eggs. Sexuelle Selektion Partnerwahl Grasfrosch Paarungstaktiken genetische Vorteile sexual selection mate choice European Common frog mating tactics genetic benefits 570 Biologie 597 Wechselwarme Wirbeltiere WT 3228 WR 7730 ddc:570 ddc:597
253	Aktivní kmitočtové filtry pro vyšší frekvence / Active Frequency Filters for Higher Frequencies Fröhlich, Lubomír January 2014 (has links) This thesis deals with the synthesis and optimization of frequency analogue filters with modern active elements usable for higher frequencies. The thesis is divided into three parts, the first part deals with the problematic concerning Leap-Frog combined ARC structure. Due to a difficult design, this method is not described in a detail and used in practice, although it shows e.g. low sensitivity. Firstly, a complete analysis of individual filters was made (for and T endings) and consequently these findings were used during implementation of this method to NAF program. Finally, samples of real filters were realized (for verification of functioning and correct design). Another very interesting topic concerning filters is usage of coupled band-pass for small bandwidth, where it is necessary to solve the problems concerning ratio of building elements values, but also price, quality, size of coils, sensitivity, Q factors, coefficients etc. That is why in practice a coil is very often substituted with other equivalent lossy and lossless blocks which create ARC filters structure. The design and the possibility of usage of lossy grounded elements were described here (such as synthetic inductors, frequency dependent negative resistor). Some parts of the design are individual computer sensitivity analysis, setting of usage and quality comparison of individual lossy grounded blocks. Besides, a program for these elements was created, it is useful for a quick design and depiction of transfer characteristics. The third part deals with the usage of tuning universal filters consisting three or more operational amplifiers, which secures its universality and possibility to create different kinds of transfer characteristic. In practice, Akerberg - Mossberg and Kerwin - Huelsman - Newcomb are the most used types of filters. These were also compared with less common universal filters. In the end, the possibility of digital tuning of universal filter with the help of digital potentiometers for filters of 10th order and frequency around 1 MHz was shown.
254	Evolutionary usage and developmental roles of vertebrate non-methylated DNA Long, Hannah Katherine January 2014 (has links) Vertebrate genomes exhibit global methylation of cytosine residues where they occur in a cytosine-guanine dinucleotide (CpG) context and this epigenetic mark is generally thought to be repressive to transcription. Punctuating this pervasive DNA methylation landscape are short, contiguous regions of non-methylated DNA which are found at two thirds of mammalian gene promoters. These non-methylated regions exhibit CpG content close to expected levels as they escape the depletion of CpGs observed across the methylated fraction of the genome. The unique nucleotide properties of these CpG island (CGI) regions enable their identification by computational prediction in mammalian genomes. Owing to a lack of high-resolution genome-wide DNA methylation profiles in non-mammalian species, these CGI predictions have often been used as a proxy for non-methylated DNA in these organisms. In contrast to mammals, CGI predictions in cold-blooded vertebrates rarely coincide with gene promoters, leading to the belief that CGls are significantly divergent between vertebrate species, and that unique promoter-associated features may have been acquired during warmblooded vertebrate evolution. This thesis is primarily concerned with the location, establishment and biological function of non-methylated islands of DNA in vertebrate genomes. To experimentally determine genome-wide profiles of non-methylated DNA, a novel biochemical technique was established called biotinylated ZF-CxxC affinity purification (Bio-CAP), and development of this method is discussed in Chapter 3. Experimental analysis of non-methylated DNA profiles in this thesis initially addresses two main questions: (1) 'How does the non-methylated DNA landscape compare genome-wide for seven vertebrates considering distinct tissue types and developmental stages?' (2) 'How are vertebrate non-methylated regions of DNA defined and interpreted in the nuclear environment?' To address the first question, non-methylated DNA was profiled by Bio-CAP sequencing across the genomes of seven diverse vertebrate species, representing all major branch points of vertebrate evolution, and the results are discussed in Chapters 4 and S. Contrary to previously held dogma, experimentally determined nonmethylated islands of DNA (NMls) constitute an ancient epigenetic feature of vertebrate gene regulatory elements. However, despite having numerous high-resolution maps of vertebrate non-methylated DNA, the means by which NMls are identified and maintained in the nuclear environment remains poorly understood. To address the second question and identify features which determine the methylation state of DNA, exogenous DNA sequences were introduced into mouse embryonic stem (ES) c~.II~. Non-methylated DNA was profiled by Bio-CAP sequencing to investigate how different features, such as sequence-specific binding motifs, chromatin architecture and nucleotide composition of a given DNA sequence impact local DNA methylation patterns. Interestingly, the majority of exogenous promoters were appropriately non-methylated in mouse ES cells, germline and somatic cells suggesting that gene promoters have retained strong signals for the nonmethylated state across millions of years of evolution (discussed in Chapter 6). During mouse embryogenesis, genome-scale DNA demethylation and remethylation events occur to remodel the epigenetic landscape and loss of DNA methylation during this time leads to embryonic lethality. To investigate the biological function of non-methylated DNA, the third question addressed in this thesis is (3) 'What is the developmental importance of non-methylated islands of DNA during vertebrate embryogenesis?' To investigate this, members of the ZF-CxxC domain-containing family of chromatin modifiers were ablated in zebrafish embryos to perturb the chromatin landscape at NMls, and therefore interfere with their function during early development (Chapter 7). Early embryonic development and patterning was disrupted in knockdown embryos, suggesting that interpretation of non-methylated DNA and placement of chromatin modifications at NMls is essential for normal zebrafish embryogenesis. Together this work sheds light on the evolutionary origins of NMls, the mechanisms involved in the recognition and establishment of nonmethylated loci and provides an insight into the function of non-methylated DNA during early embryonic development. 572.8
255	Elektronické filtrační obvody s obecnými kmitočtovými charakteristikami / Electronic Filtering Circuits with Arbitrary Frequency Characteristics Klubus, Jan January 2020 (has links) Master’s thesis deals with the issue of electronic filtering circuits with arbitrary frequency characteristics. First part of the thesis describes theoretical basis. Second part explores the possibilities of design procedures for filters with arbitrary frequency characteristics. Design procedures are demonstrated on examples accordingly to the presented methods, including their circuit implementation and computer simulation to verify the correctness of theoretical assumptions. Thesis also explores the possibilities of tuning circuit structures and electronic setting for characteristics using controllable active elements.
256	Breccia of Frog Lakes : reconstructing Triassic volcanism and subduction initiation in the east-central Sierra Nevada, California Roberts, Sarah Elizabeth 12 March 2014 (has links) Indiana University-Purdue University Indianapolis (IUPUI) / The Antler and Sonoma orogenies occurred along the southwest-trending passive Pacific margin of North America during the Paleozoic concluding with the accretion of the McCloud Arc. A southeast-trending sinistral transform fault truncated the continental margin in the Permian, becoming a locus for initiation of an east-dipping subduction zone creating the Sierran magmatic arc. Constrained in age between two early Triassic tuff layers, the volcanic clasts in the breccia of Frog Lakes represent one of the earliest records of mafic magmatism in the eastern Sierra Nevada. Tholeiitic rock clasts found in the breccia of Frog Lakes in the Saddlebag Lake pendant in the east central Sierra Nevada range in composition from 48% to 63% SiO2. Boninites produced by early volcanism of subduction initiation by spontaneous nucleation at the Izu-Bonin-Mariana arc are more depleted in trace element concentrations than the clasts while andesites from the northern volcanic zone of the Andes produced on crust 50 km thick have similar levels of enrichment and provide a better geochemical modern analogue. Textural analysis of the breccia of Frog Lakes suggest a subaqueous environment of deposition from a mature magmatic arc built on continental crust > 50 km thick during the Triassic. The monzodiorites of Saddlebag and Odell Lakes are temporal intrusive equivalents of the breccia of Frog Lakes and zircon geochemistry indicates a magmatic arc petrogenesis. Paleoseismology Continental margins Plate tectonics Geology, Stratigraphic -- Triassic Geophysics -- Pacific Area Geophysics -- Washington (State) Geophysics -- Nevada -- Sonoma Range Intrusions (Geology) Phenocrysts Roof pendants (Geology) -- Research Orogeny -- Nevada Odell Lake (Or.) Klamath Mountains (Calif. and Or.) Magmatism
257	Dr. Eleine Mad Jacobsson, Madeleine January 2021 (has links) Dr. Eleine Mad är Madeleine Jacobsssons talesperson för dom vetenskapliga och paranormala upptäckter som uppstår i hennes världar. Hon beskriver innehåll, teknik och estetik utifrån ett kategoriseringssytem där konsten delas upp som olika typer av komponenter och därefter avkodas dessa allteftersom. För att förstå intuitionens inblandning i arbetsprocessen omförvandlas den till tre separata roller av en Sökare, Samlare och Myntare. Med rollerna försöker jag beskriva på vilka sätt som intuitionen är till gagn eller av förödelse för det konstnärliga arbetet. Sagan om M handlar om en grodlik karaktär, Delop, som lämnar sin hemplanet för att uppsöka andra världar. I sitt sökande hittar Delop ett folkslag vars syn och levnadssätt skiljer sig från hennes erfarenheter av “verkligheten” såsom hon lärt sig att överleva i den. / Dr. Eleine Mad is Madeleine Jacobsson's spokesperson for the scientific and paranormal discoveries that arise in her worlds. She describes content, tecniques and aesthetics based on a categorization system where art is divided into different types of components and then decoded as they go. To understand the intuition's involvement in the work process, it is transformed into three separate roles by a Seeker, Collector and a Myntare(In swedish language the one who is a "myntare" -is verbally declaring a concept or term). With these roles I try to describe in what ways intuition is beneficial or devastating to the artistic work. The story of M is about a frog-like character, Delop, who leaves the home planet to seek out other worlds. In her search, Delop finds a world whose views and lifestyles differ from her experiences of "reality" as she learned to survive in it. / <p>Recorded sound and image material of the presentation is available for private use.</p> mjjgkjacb longing desire pang aj worlds shark genital symbol female sexuality worlds content the tale of M Doctor M mad life artifact animals figures emotional states red existentialism epicenter dog mythology folk beer whistle closeness aversions seeker collector myntare stagnation hibernation intuition sausage soup majdalakdemlsmikopa Delop Cow Lice snake hare sheep ödel oktor threat antipathy empathy fear performance function allow belief clitoral heroes monsters pink components situation dual nature euphoria bic-pens reality violence desert sea AQB brain holistics social codes self fairy tale space blue horse hell gotland dizzying flourish anthropomorphic jewels death plaster spiders commit survive frog whale bear purpose communication wild fascination animal incomparable monster ugly disturbed perspective marauder green symbolism who suffer anger reverence gods recast transformation yellow pry entrance interest alternative insignificant rigid position of power as disease real added disgusting wake up doubt mourn pray images horror plants rock stop mjjgkjacb längtan åtrå pang aj världar haj världsallt könssymbol kvinnlig sexualitet världarnas innehåll sagan om M Doktor M mad livet artefakt djur figurer känslomässiga tillstånd röd existentialism epicentrum hund mytologi folköl vissla närhet aversioner sökare samlare myntare stagnation dvala intuition korvsoppa majdalakdemlsmikopa Delop Ko Löss orm hare får Ödel Oktor hot antipati empati rädsla föreställning funktion tillåta tro klitorala hjältar monster rosa världar komponenter situation dubbla natur eufori bic-pennor verkligheten våld öken hav A.Q.B hjärna holistisk sociala koder självet sagorymd blå häst helvete Gotland vimmelkantig florera antropomorf juveler döden plåsterspindlar vägvisare begå överleva groda val björn syfte kommunicering vild fascination djurisk makalös vidunder ful störd perspektiv marodör grön symbolism vem genomlida ilska vördnad gudar omstöpt sammandrabbningar transformation gul bända ingång intresserar alternativ oväsentlig stel maktposition som sjukdom verkligt tillsatt äcklig vakna tvivla sörja be urbilder skräck växter rock stopp Arts Konst
258	From Snow White to Frozen : An evaluation of popular gender representation indicators applied to Disney’s princess films / Från Snövit till Frost : En utvärdering av populära könsrepresentations-indikatorer tillämpade på Disneys prinsessfilmer Nyh, Johan January 2015 (has links) Simple content analysis methods, such as the Bechdel test and measuring percentage of female talk time or characters, have seen a surge of attention from mainstream media and in social media the last couple of years. Underlying assumptions are generally shared with the gender role socialization model and consequently, an importance is stated, due to a high degree to which impressions from media shape in particular young children’s identification processes. For young girls, the Disney Princesses franchise (with Frozen included) stands out as the number one player commercially as well as in customer awareness. The vertical lineup of Disney princesses spans from the passive and domestic working Snow White in 1937 to independent and super-power wielding princess Elsa in 2013, which makes the line of films an optimal test subject in evaluating above-mentioned simple content analysis methods. As a control, a meta-study has been conducted on previous academic studies on the same range of films. The sampled research, within fields spanning from qualitative content analysis and semiotics to coded content analysis, all come to the same conclusions regarding the general changes over time in representations of female characters. The objective of this thesis is to answer whether or not there is a correlation between these changes and those indicated by the simple content analysis methods, i.e. whether or not the simple popular methods are in general coherence with the more intricate academic methods. / <p>Betyg VG (skala IG-VG)</p> Disney princesses Disney princesses gender Bechdel Bechdel test Walt Disney Pixar Frozen children girl culture gender representations talk time talktime gendertimer equality content analysis female feminism feminist gender role socialization model gender role socialization model passive domestic active media post-feminist gender role portrayals key measures popular nature or nurture genes or environment gender differences expressions of gender gender experiments neurological brain plasticity constructivist cultivation theory social cognitive theory quantitative quantitative measures quantitative methods stereotypes stereotype stereotypical women character count biological sex biological gender metrics femininity textual analysis submissive submissive behaviour independence daddy's girl patriarchy patriarchal patriarchal approval wicked women old wicked women wicked witch male masculine masculine characteristics feminine characteristics genders marrying marriage love at first sight empowerment fairy tale fairy tales film movie films movies Mulan Pocahontas Snow White Snow White and the seven dwarfs Cinderella Sleeping Beauty Little Mermaid The Little Mermaid Beauty and the Beast Aladdin Tangled Brave Frozen The Princess and the Frog Merida relationship relationship formation true love true love's kiss sisterhood sisterly Grimm Grimm brothers parental approval matriarchal approval matriarchal matriarchy stereotyping evil queen rate rater rating measure measuring wicked stepmother binary gender gender binarity binary genders gender identities gender identity gender identity formation identity formation animation cell animation the Smurfette principle strong women strong girls girlie positivism positivistic film studies analysis analyses antagonism action coding cultivation effect cultivation effects socialization effect socialization effects coded content analysis simple metrics cognition theory connotations cultivation theory socialization theory depictions of femininity plasticity human brain damsels in distress feminist research inequality gender inequality media studies heroines mass media social media images of women woman as image reading interpretation modern day fairy tales Disney prinsessor Disneyprinsessor Disney-prinsessor kön genus genusvetenskap Bechdel Bechdel test Bechdeltest Bechdeltestet Walt Disney Pixar Frost barn flickor kulturuppväxt representationer skildringar intryck taltid talk time talktime gendertimer jämlikhet innehållsanalys feminin feminism könsroll könsroller socialisering socialiseringsmodellen passiv hushållsarbete aktiv media post-feministisk postfemininstisk nyckeltal populärvetenskaplig populärvetenskapligt naturen uppväxt eller gener gener eller upppväxt uppfostran genetik könsskillnader könsuttryck experiment hjärnan plasticitet konstruktivism kultivationsteori kognitiv teori kvantitativ kvantitativa mått kvantitativa metoder stereotyper stereotyp stereotypisk kvinnnor kvinna kön biologiskt kön mått nyckeltal femininitet textanalys filmanalys kuvad underkastad submissiv oberoende pappas flicka patriarkat patriarkisk patriarkalt godkännande manlig maskulin kön genus äktenskap kärlek vid första ögonkastet saga sagor bröderna Grimm film Mulan Pocahontas Snövit och de sju dvärgarna Askungen Törnrosa Den lilla Sjöjungfrun Skönheten och Odjuret Aladdin Trassel Modig Frost Prinsessan och Grodan Merida förhållanden sann kärlek Grimm matriark matriarkisk patriarkalt godkännande matriarkalt godkännande bedöma betygsätta mått mäta ond styvmor binära kön könsidentitet könsidentiteter animation Smurfan starka kvinnor starka flickor positivistisk positivism filmvetenskap filmstudier antagonism protagonist hjältinna kodning kultivationseffekten socialiseringseffekten socialisationseffekten kodad innehållsanalys förenklade mått kognitiv teori konnotationer konnotera feministisk forskning könsbalans mediastudier mediestudier massmedia social media bilder av kvinnor kvinnan som bild images of women woman as image reading interpretation modern day fairy tales tolkning

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