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Triggas hannar av honlig lukt? : en beteendestudie på tångsnälla (Syngnathus typhle) i ÖstersjönLindqvist, Charlotte January 2010 (has links)
<p>The brood-nosed pipefish <em>Syngnathus typhle</em> is a pipefish with reversed sex roles. Males prefer to mate with large and ornamented females and females compete for partners. It has previously been shown that males mate more randomly when water becomes turbid.</p><p>In the Baltic Sea eutrophication has become a severe problem with turbid waters as one consequence. Turbidity makes visual cues less effective and thus weakens sexual selection in species using vision to discriminate between partners. It also affects mate encounter rates in species using vision to find each other. A lower mate encounter rate means a weakening of sexual selection and that individuals mate more randomly. One way to compensate for lower visibility would be to use olfactory cues instead. In this study I investigated whether <em>S. typhle</em> could use olfactory cues to discriminate between sexes. I found no support that they could use olfactory cues to find a partner.</p>
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Immuntechnologische Verfahren zum Aufbau homogener Immunoassays sowie zur Selektion Antikörper produzierender Zellen / Immunotechnological procedures for the development of homogeneous immunoassays and the selection of antibody producing cellsSellrie, Frank January 2007 (has links)
Homogene Immunoassays sind immunologische Testverfahren, bei deren Durchführung vollständig auf Separations- und Waschschritte verzichtet werden kann.
Der Substrate Channeling Immunoassay beruht auf der Weitergabe eines Substrates in einem immunologischen Komplex aus zwei Enzymen. Das Produkt des ersten Enzyms dient dem zweiten Enzym als Substrat zur Generierung eines photometrisch nachweisbaren Produktes. Voraussetzung für diese Weitergabe ist die enge räumliche Nähe beider Enzyme. Diese Nähe wird durch eine Bindung zwischen Analyt und anti-Analyt Antikörper vermittelt. Ein solcher Substrate Channeling Immunoassay wurde unter Verwendung der Enzyme Glucoseoxidase und Peroxidase aufgebaut. Das so etablierte System war funktionstüchtig, jedoch blieb seine Sensitivität hinter der normaler, heterogener Immunoassays zurück.
Die Grundlage eines Fluorescence Quenching Immunoassays ist der gegenseitige Ausschluß zweier Antikörper bei der Bindung eines Dihapten-Konjugates. Das Konjugat besteht dabei aus dem Analyten und einem Fluorophor. Die beiden um die Konjugatbindung konkurrierenden Antikörper sind ein anti-Analyt Antikörper und ein anti-Fluorophor Antikörper, der zudem über die Eigenschaft verfügt, bei Bindung des Fluorophors dessen Fluoreszenz zu löschen. Externe Gaben des freien Analyten verschieben das eingestellte Gleichgewicht in Richtung Fluorophor-Bindung und damit Fluoreszenz-Löschung. Die Änderung der Fluoreszenz ist direkt an die Konzentration des freien Analyten gekoppelt und dient zu deren Bestimmung. Ein solcher Fluorescence Quenching Immunoassays wurde für die Konzentrationsbestimmung des Herbizides Diuron etabliert. Die erreichten Sensitivitäten erlauben die praktische, immundiagnostische Anwendung des Systems.
Ein Dihapten-Konjugat wurde ebenfalls zum Aufbau eines Verfahrens zur Selektion Antikörper produzierender Zellen eingesetzt.
Die Selektion der Antikörper produzierenden Zellen erfolgt unter Verwendung eines Toxinkonjugates. Dieses Konjugat besteht aus einem Liganden und einem Toxin. Die Antikörperbindung des Liganden behindert sterisch die Wechselwirkung der Toxinkomponente im Konjugat mit deren Zielstruktur in oder auf der Zelle. Nur Zellen die einen geeigneten Antikörper sezernieren, überleben die Selektion und reichern sich in der Kultur an. Das Selektionsverfahren wurde erfolgreich für die Selektion von E.coli Zellen eingesetzt, die einen rekombinanten, Fluorescein bindenden Antikörper produzierten. Das hierfür synthetisierte Toxinkonjugat bestand aus Fluorescein (Ligand) und Ampicillin (Toxinkomponente). Eine Ablösung der bisher für diese Aufgabe gebräuchlichen, außerordentlich kostenintensiven, Screening Methoden wird damit möglich. / Homogeneous immunoassays are test systems which do not depend on separation steps. The substrate channeling immunoassay is based on the product/substrate transfer in an immunological complex built up by two enzymes. The product of the first enzyme functions as substrate for the second enzyme. The second enzyme generates a photometrically detectable product. The close proximity of these two enzymes is the basis of the substrate channeling. This proximity is created by antibody binding to the corresponding analyte. The enzymes glucose oxidase and peroxidase were used for the development of such an assay system. The established homogeneous immunoassay was functional. But the sensitivity of the assay was much lower than that of conventional heterogeneous immunoassays.
The principle of a fluorescence quenching immunoassay is based on the fact that two antibodies exclude each other from binding to a dihapten conjugate. The conjugate consists of the analyte and the fluorophore. The two antibodies which compete for the conjugate binding are an anti-analyte antibody and an anti-fluorophore antibody. This anti-fluorophore antibody quenches the fluorescence of the fluorophore after binding. The addition of free analyte alters the equilibrium of the system so that the anti-fluorophore antibody is bound to the fluorophore and the fluorescence is quenched. The change in fluorescence is therefore an indicator of the concentration of free analyte added. A homogeneous fluorescence quenching immunoassay was established for the determination of the herbicide diuron. The sensitivities obtained allow the practical immunodiagnostic application of the system.
A dihapten conjugate was also employed for the development of a selection method for antibody-producing cells. Toxin conjugates were used in this system. Each conjugate consisted of a ligand and a toxin. Antibody binding to the ligand sterically inhibits the toxin component to interact with its target structure. Only cells secreting a binding antibody will survive the selection and will accumulate in culture. The system was applied to the selection of E.coli cells producing a recombinant fluorescein-binding antibody. The toxin conjugate used in experiment consisted of fluorescein (ligand) and ampicillin (toxin component). This selection procedure allowed the isolation of recombinant antibody-producing E.coli cells. It has the potential to replace the time-consuming and labour-intensive methods used so far.
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Male Reproductive Strategies in Verreaux's Sifaka (Propithecus verreauxi) / Reproduktionsstrategien der Männchen beim Larven-Sifaka (Propithecus verreauxi)Mass, Vanessa 23 April 2009 (has links)
No description available.
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Die Implementierung der Selektion gegen Osteochondrose in ein Zuchtprogramm beim Warmblutpferd / Evaluation of breeding strategies against osteochondrosis in warmblood horsesBusche, Stephanie-Mabinti 18 November 2005 (has links)
No description available.
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Marker Assisted Selection for the development of intervarietal substitution lines in rapeseed <i>(Brassica napus L.)</i> and the estimation of QTL effects for glucosinolate content / Markergestützte Selektion für die Entwicklung von intervarietalen Substitutionslinien bei Raps <i>(Brassica napus L.)</i> und die Schätzung von QTL-Effekten für Glucosinolatgehalt. / Seleção assistida por marcadores para o desenvolvimento de linhas de substituição invervarietais em colza <i>(Brassica napus L.)</i> e estimativa do efeito dos QTL para teor de glucosinolatosMarschalek, Rubens 17 July 2003 (has links)
No description available.
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Growth curve and body weight in Göttingen minipigs - a phenotypic and genetic study / Wachstumskurve und Körpergewicht beim Göttinger Minischwein - eine phänotypische und genetische StudieKöhn, Friederike 15 November 2007 (has links)
No description available.
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Development of Integration Algorithms for Vision/Force Robot Control with Automatic Decision SystemBdiwi, Mohamad 12 August 2014 (has links) (PDF)
In advanced robot applications, the challenge today is that the robot should perform different successive subtasks to achieve one or more complicated tasks similar to human. Hence, this kind of tasks required to combine different kind of sensors in order to get full information about the work environment. However, from the point of view of control, more sensors mean more possibilities for the structure of the control system. As shown previously, vision and force sensors are the most common external sensors in robot system. As a result, in scientific papers it can be found numerous control algorithms and different structures for vision/force robot control, e.g. shared, traded control etc. The lacks in integration of vision/force robot control could be summarized as follows:
• How to define which subspaces should be vision, position or force controlled?
• When the controller should switch from one control mode to another one?
• How to insure that the visual information could be reliably used?
• How to define the most appropriated vision/force control structure?
In many previous works, during performing a specified task one kind of vision/force control structure has been used which is pre-defined by the programmer. In addition to that, if the task is modified or changed, it would be much complicated for the user to describe the task and to define the most appropriated vision/force robot control especially if the user is inexperienced. Furthermore, vision and force sensors are used only as simple feedback (e.g. vision sensor is used usually as position estimator) or they are intended to avoid the obstacles. Accordingly, much useful information provided by the sensors which help the robot to perform the task autonomously is missed.
In our opinion, these lacks of defining the most appropriate vision/force robot control and the weakness in the utilization from all the information which could be provided by the sensors introduce important limits which prevent the robot to be versatile, autonomous, dependable and user-friendly. For this purpose, helping to increase autonomy, versatility, dependability and user-friendly in certain area of robotics which requires vision/force integration is the scope of this thesis. More concretely:
1. Autonomy: In the term of an automatic decision system which defines the most appropriated vision/force control modes for different kinds of tasks and chooses the best structure of vision/force control depending on the surrounding environments and a priori knowledge.
2. Versatility: By preparing some relevant scenarios for different situations, where both the visual servoing and force control are necessary and indispensable.
3. Dependability: In the term of the robot should depend on its own sensors more than on reprogramming and human intervention. In other words, how the robot system can use all the available information which could be provided by the vision and force sensors, not only for the target object but also for the features extraction of the whole scene.
4. User-friendly: By designing a high level description of the task, the object and the sensor configuration which is suitable also for inexperienced user.
If the previous properties are relatively achieved, the proposed robot system can:
• Perform different successive and complex tasks.
• Grasp/contact and track imprecisely placed objects with different poses.
• Decide automatically the most appropriate combination of vision/force feedback for every task and react immediately to the changes from one control cycle to another because of occurrence of some unforeseen events.
• Benefit from all the advantages of different vision/force control structures.
• Benefit from all the information provided by the sensors.
• Reduce the human intervention or reprogramming during the execution of the task.
• Facilitate the task description and entering of a priori-knowledge for the user, even if he/she is inexperienced.
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Triggas hannar av honlig lukt? : en beteendestudie på tångsnälla (Syngnathus typhle) i ÖstersjönLindqvist, Charlotte January 2010 (has links)
The brood-nosed pipefish Syngnathus typhle is a pipefish with reversed sex roles. Males prefer to mate with large and ornamented females and females compete for partners. It has previously been shown that males mate more randomly when water becomes turbid. In the Baltic Sea eutrophication has become a severe problem with turbid waters as one consequence. Turbidity makes visual cues less effective and thus weakens sexual selection in species using vision to discriminate between partners. It also affects mate encounter rates in species using vision to find each other. A lower mate encounter rate means a weakening of sexual selection and that individuals mate more randomly. One way to compensate for lower visibility would be to use olfactory cues instead. In this study I investigated whether S. typhle could use olfactory cues to discriminate between sexes. I found no support that they could use olfactory cues to find a partner.
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Gene regulatory factors in the evolutionary history of humansPerdomo-Sabogal, Alvaro 13 October 2016 (has links) (PDF)
Changes in cis- and trans-regulatory elements are among the prime sources of genetic and phenotypical variation at species level. The introduction of cis- and trans- regulatory variation has played important roles in driving diversity, phenotypical differentiation, and evolution of humans. Therefore, variation that occurs on cis- and trans- regulatory elements becomes imperative to better understanding of human genetic diversity and its evolution.
In this research, around 3360 gene regulatory factors (GRF) from the human genome were catalogued. This catalog includes genes that code for proteins that perform gene regulatory activities such DNA-depending transcription, RNA polymerase II transcription cofactor and co-repressor activity, chromatin binding and remodeling, among other 218 regulatory functions. This GRF catalog allowed us to initially explore how some GRF genes have evolved in humans, archaic humans (Neandertal and Denisovan) and non-human primate species. We discussed the likely phenotypical and medical effects that evolutionary changes in GRF genes may have introduced into the human genome; for instance, traits associated to speech and language capabilities, genomic recombination hotspots, diseases, among others.
By using genome-wide datasets, we additionally looked for GRFs likely to be candidates for positive selection in three human populations: Utah Residents with Northern and Western Ancestry (CEU), Han Chinese in Beijing (CHB), and Yoruba in Ibadan (YRI). As result, we produced a set of candidates that gathers genes that may have contributed in shaping the phenotypical diversity currently observed in these populations; for instance, by introducing regulatory diversity at population-specific level. We additionally identified six GRF classes enriched for genes located in regions that are likely candidates for positive selection at population specific level. We found that out of the 41 DNA-binding GRF classes classified so far, six groups exhibited enrichment for genes located on regions that may have been under positive selection: C2H2 zinc finger, KRAB-ZNF zinc finger, Homeo domain, Tryptophan cluster, Fork head/winged helix and, and High-mobility HMG domain. We additionally identified three KRAB-ZNF gene clusters, in the chromosomes one, three, and 16, for the Asian population that exhibit regions with extended haplotype homozygosity EHH (larger than 100 kb). This EHH suggests that these regions have undergone positive selection in CHB population.
Finally, considering that a representative fraction of the phenotypic diversity observed between humans and its closely related species are likely explained by changes in cis-regulatory elements (CREs), we investigated putative binding sites for the transcription factor GABPa. Using ChIP-Seq data generated from a human cell line (HEK293T), 11,619 putative GABPa CREs were found, Out of which 224 are putative human-specific. To experimentally validate the transcriptional activity of these human-specific CREs, reporter gene essays and knock-down experiments were performed. Our results supported the functionality of these human-specific GABPa CREs and suggest that at least 1,215 genes are primary targets of GABPa. Finally, further analyses depict scenarios that put together transcriptional regulation by GABPa and the evolution of particular human traits; for instance, cognitive abilities, breast morphology, lipids and glucose metabolic pathways, among others.
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Einflussfaktoren auf die Wahrnehmung von UnordnungKohlmeier, Markus 16 December 2020 (has links)
Der Beitrag untersucht die Wirkung verschiedener Einflussfaktoren auf die Perzeption von Unordnung. Einer Einführung in die theoretische Diskussion rund um die Wirkung von Unordnung auf das urbane Sozialgefüge folgen verschiedene multivariate Berechnungen (N = 2003). Hierzu wird ein additiver Index aus dem Produkt von subjektiver Schwere und perzipierter Häufigkeit verschiedener Erscheinungsformen physischer und sozialer Unordnung gebildet. Die Regressionsergebnisse zeigen, dass die soziale Struktur urbaner Nachbarschaften, der bedingte Erwartungswert für die kollektive Wirksamkeit informeller Sozialkontrolle sowie solche Prädiktoren, welche die Bedeutung des unmittelbaren sozialen Nahraumes für Prozesse kognitiver Dissonanzbewältigung betonen (Viktimisierung, Wohnverhältnis, Kriminalitätseinstellungen), erklären, wann ein Akteur eine Situation als unsicher definiert und infolgedessen Unordnung als Anzeichen von Gefahr interpretiert. Der dem Explanans zugrundeliegende soziale Mechanismus beruht auf der Theorie der Frame-Selektion nach Esser (1991). Die Untersuchung basiert auf der Sicherheitsbefragung der Stadt Leipzig (2011).:1 Einleitung
2 Theorie
2.1 Hunter (1978)
2.2 Wilson und Kelling (1982)
2.3 Exkurs
2.4 Lewis und Salem (1986)
2.5 Skogan (1990)
2.6 Das Konzept der collective efficacy
3 Hypothesen
3.1 Der Grundzusammenhang des theoretischen Modells
3.2 Die Brückenhypothesen des Modells
3.2.1 Direkte und indirekte Viktimisierung
3.2.2 Kriminalitätsfurcht
3.2.3 Medienrezeption
3.2.4 Kontrollvariablen
4 Daten, Operationalisierungen, Methoden
4.1 Daten
4.2 Operationalisierungen
4.2.1 Abhängige Variable(n)
4.2.2 Unabhängige Variablen
4.3 Methoden
5 Auswertung
5.1 Bivariate Ergebnisse
5.2 Multivariate Ergebnisse
6 Fazit und abschließende Bemerkungen
7 Anhang
8 Literaturverzeichnis / This article investigates the influence of various predictors on the perception of disorder. An introduction to the theoretical discussion about the impact of disorder on the urban social structure is followed by different multivariate regressions (N = 2003). The perception of different images of physical and social disorder is measured in terms of the sentimental value of disorder and the perceived frequency of disorder. An additive index using product terms of the sentimental value and the perceived frequency for each image is constructed. The results of the regressions indicate that social structure of urban neighborhoods, collective efficacy, and such predictors which aim at the significance of social proximity (victimization, housing situation, personal crime settings) for processes of cognitive dissonance coping explain when an actor defines a situation as not-secure and subsequently interprets disorder as a symbol of danger. Esser’s (1991) theory of frame-selection functions as the social mechanism of the explanans. The hypotheses are tested on survey data provided by the city of Leipzig (2011).:1 Einleitung
2 Theorie
2.1 Hunter (1978)
2.2 Wilson und Kelling (1982)
2.3 Exkurs
2.4 Lewis und Salem (1986)
2.5 Skogan (1990)
2.6 Das Konzept der collective efficacy
3 Hypothesen
3.1 Der Grundzusammenhang des theoretischen Modells
3.2 Die Brückenhypothesen des Modells
3.2.1 Direkte und indirekte Viktimisierung
3.2.2 Kriminalitätsfurcht
3.2.3 Medienrezeption
3.2.4 Kontrollvariablen
4 Daten, Operationalisierungen, Methoden
4.1 Daten
4.2 Operationalisierungen
4.2.1 Abhängige Variable(n)
4.2.2 Unabhängige Variablen
4.3 Methoden
5 Auswertung
5.1 Bivariate Ergebnisse
5.2 Multivariate Ergebnisse
6 Fazit und abschließende Bemerkungen
7 Anhang
8 Literaturverzeichnis
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