Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 18 of 18 for “"Chemical signalling"”.
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Electrochemical and microscopic analysis of chemical signalling in biological systems
… the highly controlled and regulated release of chemical signals through a process known as exocytosis. This process consists of organelles known as vesicles fusing with the plasma membrane to release the content inside to the extracellular space. Although the basic underpinnings of this process …
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Piezo1-dependent mechanical regulation of chemical signalling in the developing Xenopus laevis brain
… by various chemo-mechanical signals. Major chemical signals include semaphorins, slits, netrins and ephrins/Eph, whereas mechanical signals include tissue stiffness, viscosity and cellular forces. In the developing embryo, chemical and mechanical signals are not isolated. However, how cells …
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Interplay between Piezo1-mediated mechanosensing and the chemical guidance cue Semaphorin3A during development of the embryonic nervous system
… of the optic tract, RGC axons respond to both chemical and mechanical signals in the environment. A key player in sensing mechanical cues is the mechanosensitive ion channel (MSC) Piezo1. Perturbations of Piezo1 resulted in aberrant axon guidance in vivo. When I studied Piezo1 downregulation …
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The role of Biophotons in cellular senescence.
… evidence that cells can influence each other non-chemically via biophotons. In this study, I aim to elucidate the potential impact of both intrinsic biophotonic emissions and extrinsic light exposure on cellular senescence. To achieve this, I developed, utilising doxorubicin (Dox), four different …
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Pheromones in Heliconius butterflies: Chemical ecology, genetics, and behaviour
Sex pheromones are chemical signals that mediate communication between males and females of a species and are important for mating. They have been well-studied in female moths, where females release volatile compounds to attract males over long distances. Butterflies fly during the day and were …
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Connectomics of extrasynaptic signalling: applications to the nervous system of Caenorhabditis elegans
… it is well established that long-distance chemical signalling via extrasynaptic volume transmission is also critical to brain function. As these interactions are not visible in the physical structure of the nervous system, current approaches to connectomics are unable to capture them. This …
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Factors regulating transitions among life cycle phases in the marine pennate diatom <i>Pseudo-nitzschia multistriata</i>
… is a density-dependent event, regulated by a chemical mediator. Support for this latter hypothesis was provided by experiments on single parental strains which underwent gametogenesis and formation of gametes when exposed to culture medium conditioned by the growth of the opposite mating type. …
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Advanced Fluorescence Lifetime Imaging and Spectroscopy Techniques for Biological Samples
… diseases, and it also affects the metabolism and chemical signalling. In this thesis, fluorescence-based studies were conducted on a fluorescent molecular rotor, BODIPY-Ci2, which was used to measure the intracellular viscosity. BODIPY-C12 is insensitive to the surrounding polarity using …
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The behavioural function of pheromones in crayfish
… efficiency for population control, however the chemical identity of crayfish pheromones is unknown. An incomplete understanding of chemical communication has delayed progress in the development of appropriate bioassays. This thesis therefore focused on researching the natural context of chemical …
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Making Scents of Butterfly Pheromone Evolution
Insect chemical profiles are diverse and complex, reflecting the wide range of functions they serve. Volatile compounds are used in foraging, defence, and mating, and pheromones are particularly important to the lives of insects. These are chemical signals that mediate the behaviour of …
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Quorum sensing for improved production of industrially useful products from filamentous fungi
… and release of low molecular weight, diffusible chemical signalling molecules, known as quorum sensing molecules (QSM) in the extracellular milieu. When the concentrations of the QSMs reach a critical threshold corresponding to a particular cell density, they bind to a receptor enabling them to …
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Role of multicellular organisation in mesoderm differentiation
… by change in exposure to secreted extracellular signalling molecules. However, recent evidence in multiple vertebrate systems has shown that tissue architecture and tissue mechanics can influence and causally feedback into cell fate decision-making processes. During gastrulation in the mouse …
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The mechanical regulation of Eph/ephrin signalling in the developing Xenopus brain
… progress in our understanding of Eph/ephrin signalling in neural development, discrepancies between in vitro and in vivo work remain. As axon pathfinding is regulated by chemical and mechanical signals, and the mechanical regulation of Eph/ephrin signalling is currently poorly understood, I …
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Communication in the hymenoptera : chemistry, ecology and evolution
… exhibit complex systems of communication with chemical signalling being the most important mode. Although there are many studies on chemical communication in insects, the evolution of chemical signals is not well understood. Due to the conflict of interests between individuals, different …
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Substrate stiffness tunes the neuronal response to the chemical guidance cue semaphorin3A
… examined how growth cones sense and respond to chemical guidance cues. However, the nervous system presents a rich and varied mechanical environment, and neuronal growth cones also respond strongly to physical stimuli. Previous work from the Franze research group identified that tissue stiffness …
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Identifying novel roles for basement membrane-associated proteins in the adult Drosophila intestinal epithelium
… integrate an array of information, including chemical, mechanical and adhesion-based cues, which collectively provide the instructions to direct cellular behaviour. A potential source of such signals is the basement membrane, a thin extracellular matrix which underlines the basal side of all …
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Mate choice in the Polychaete nereis acuminata : the role of aggression and parental experience
… in terms of physiology and release of the chemical signal however, are still unknown. It is thought that there is a physiological change in the male, for example by release of sperm or by production of ‘new’ sperm that the female can detect and uses to indicate that a male has previously …
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Conducting polymer hydrogels for the release of glutamate and sensing of extracellular action potentials
… abnormal neuronal action potential firing and chemical signalling in the brain. Conventional treatment options including oral and systemic administration of drugs have limited ability to cross the blood brain barrier and hence require frequent administration of drugs in higher doses leading to …