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Garrison, Lance Preston. "The influence of physical transport and nutritional stress on the zoeae of estuarine crabs." W&M ScholarWorks, 1997. http://web.vims.edu/library/Theses/Garrison97.pdf.
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Miller, Wyatt Austin. "Effects of molting and hyposalinity stress on the expression of HIF-a, molting, and immune response genes in juvenile Cancer magister /." Connect to title online (Scholars' Bank), 2008. http://hdl.handle.net/1794/9132.
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O'Callaghan, Felicity E. "The effect of temperature on pressure sensing in the crab Carcinus maenas (L.)." Thesis, University of Aberdeen, 2013. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=195131.
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Hydrostatic pressure sensing is used by aquatic animals to estimate depth and to synchronize behaviour with the tides. Pressure sensors examined to date depend on the compression of a fluid, making them susceptible to temperature change. Despite this, the effects of temperature on pressure sensing have not so far been researched. This thesis examined the effects of temperature on the afferent firing rate of thread hair pressure receptors in the crab Carcinus maenas. It tested the hypothesis that for sensors responding positively to rising pressure, an increase in temperature should counteract any contraction in volume, thereby leading to a weaker neural response; vice versa, a stronger response was predicted for a temperature decrease. A novel system was developed which allowed the simultaneous application of sinusoidal pressure change from 150 to 350 mbar and cycles of temperature, typically spanning between 16 and 22 °C, while extracellular recordings were made en passant from afferent nerves innervating statocyst thread hairs. Motor programmes were designed to stimulate thread hairs sensitive to clockwise and anticlockwise rotation through continuous or interrupted bouts of oscillation within the horizontal plane. During constant pressure, raising temperature led to increases in spike frequency and amplitude, with Q10s between 3 and 5 for spike frequency but less than 2 for amplitude. Cooling caused the elimination or decrease of pressure responses while increasing them on heating, thereby contradicting the aforementioned hypothesis of temperature mimicking pressure change. Changes in the timing of pressure responses were also observed. In preparations which were non-responsive to pressure change, temperature change led to bursts in firing at the peaks or troughs of pressure cycles in 28 of 42 preparations, with evidence for recruitment of formerly silent units. The results could not be fully explained under the existing model for pressure sensing by thread hairs, highlighting the necessity for further anatomical studies.
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Brian, Jayne V. "Inter-population variability in the shore crab (Carcinus maenas L.) and its potential use as a biomarker of anthropogenic effects." Thesis, Edinburgh Napier University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271275.
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Connolly, Lauren E. "Effect of predator diet on foraging behavior of panopeus herbstII in response to predator urine cues." Thesis, Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/53392.
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The ability of prey to detect and respond appropriately to predator risk is important to overall prey fitness. Many aquatic organisms assess risk through the use of chemical cues that can change with predator diet. Two variable characteristics of diet are: 1. prey type and 2. prey mass. To assess the effect of these two characteristics on the assessment of risk by the mud crab Panopeus herbstii, I exposed mud crabs to the urine of the blue crab Callinectes sapidus fed one of 5 diet treatments: 10g of oyster shell free wet mass, 5g of oyster shell free wet mass, 10g crushed mud crabs, 5g crushed mud crabs, and a mix of 5g of oyster shell free wet mass and 5g crushed mud crab. Effects on P. herbstii foraging were tested in a previously developed bioassay by measuring shrimp consumption over a 4 hour period. I hypothesized that P. herbstii would have a larger magnitude response to urine from C. sapidus fed a diet of crushed mud crabs than to urine from C. sapidus fed a diet of oysters. I further hypothesized that P. herbstii would have a larger magnitude response to urine from C. sapidus fed a high mass diet relative to a lower mass diet. Contrary to expectations there was no observed effect of urine on P. herbstii foraging in any of the treatments. Results suggest that bioassay protocol may be unreliable suggesting further replication to determine the difference between this study and previous results. Future studies examining how P. herbstii varies with urine concentration will aid in understanding the ecological scale of this predator cue system. Determining the role of other potential cue sources will improve the predictive abilities of these studies.
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Stanley, Jenni Anne. "Ambient underwater sound: measuring the importance of spatial viariability and its effect on late stage larval crabs." Thesis, University of Auckland, 2011. http://hdl.handle.net/2292/6975.
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Recent studies have shown that underwater sound emanating from coastal reefs may be used for guiding the movements of a wide range of reef organisms to suitable settlement habitats. However, it is not known whether this underwater sound is also capable of mediating the settlement and metamorphosis processes in these organisms. The present study used laboratory- and field-based methods to determine whether ambient underwater sound is used as a settlement and metamorphosis cue in 10 species of larval crabs. The settlement stage larvae of five common crab species showed marked changes in swimming behaviour consistent with settlement and showed a significant decrease in time to metamorphosis (TTM) when exposed to replayed ambient reef sound compared with a silent control. Ambient underwater sound has the potential to convey valuable information about the type and suitability of the habitat at its source to settlement stage pelagic larvae provided different habitats produce distinctive underwater sound. Analyses of recordings from several different habitat types along the coast of north-eastern New Zealand showed that the sound emanating from different habitat types had marked differences in terms of gross character, i.e., spectral composition and sound level. When habitat specific sounds were used in laboratory- and field-based experiments a significant decrease in TTM was observed for settlement stage crab larvae exposed to favourable settlement habitat sound when compared to unfavourable habitats. Behavioural thresholds for habitat sound were determined experimentally by exposing settlement stage larvae to a range of sound levels from both favourable and unfavourable habitat types for settlement. Larvae did not respond to sound from unfavourable habitat types. However, for sound from favourable habitat types for settlement most crab species showed increasing reductions in TTM as sound levels were increased, suggesting that proximity to the sound source or settlement habitat is important in inducing faster settlement. The results presented in this thesis demonstrate that ambient underwater sound originating from coastal habitats mediates the settlement processes of the megalopae of many common coastal crab species in both temperate and tropical waters. It provides evidence that differences in the spatial and biological characteristics of underwater sound play a significant role in this process. Overall, the results of this research greatly extend our knowledge of the importance of underwater sound to recruitment processes of coastal larvae.Whole document restricted until August 2012, but available by request, use the feedback form to request access.
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Dölle, Michael. "Field effect transistor based CMOS stress sensors /." Tönning ; Lübeck Marburg : Der Andere Verlag, 2006. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=016086105&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Maliphant, Paula. "The effect of pesticide stress on diatoms." Thesis, University of Hertfordshire, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309720.
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Chung, Samwon. "The effect of internal stress on diffusion." Case Western Reserve University School of Graduate Studies / OhioLINK, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=case1058210791.
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MACHADO, VERONICA MIQUELIN. "EFFECT OF ELASTIC-PLASTIC STRESS IN THE DEFECT TOLERANCE UNDER STRESS CORROSION CRACKING." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2016. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33679@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCOORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE EXCELENCIA ACADEMICA
Corrosão sob tensão (SCC), que consiste na iniciação e propagação de trincas devido ao efeito combinado de tensões mecânicas e o ambiente corrosivo, é um dano potencial para estruturas e componentes. Além do mais, SCC pode ser explicado por diferentes mecanismos dependendo do par material ambiente corrosivo considerado, o que dificulta o uso de um modelo geral para predizer o comportamento de trincas em SCC. Sendo assim, projetos frequentemente utilizam um critério conservativo que desqualifica materiais susceptíveis à SCC sem analisar de maneira apropriada a influência dos campos de tensão que a induzem. O objetivo deste trabalho é avaliar o efeito de tensões elastoplásticas na corrosão sob tensão. Esta abordagem mecânica considera que todos os efeitos corrosivos envolvidos na corrosão sob tensão podem ser apropriadamente quantificados pelas tradicionais resistências do material à iniciação e propagação de trincas para um ambiente corrosivo específico. Corpos de prova de flexão em Alumínio fragilizados por Gálio líquido serão utilizados para prever o efeito de tensões residuais induzidas por deformações plásticas na iniciação de trincas por corrosão sob tensão. Além disso, uma análise quantitativa baseada no comportamento de trincas não propagantes a partir de entalhes será usada para estimar a tensão necessária para iniciar e propagar trincas em corpos de prova entalhados em aço AISI 4140 sujeitos à corrosão por sulfeto de hidrogênio em ambiente aquoso. O comportamento de trincas curtas e a carga máxima suportada pelos corpos de prova entalhados são analisadas considerando campos de tensões lineares elástico e elastoplásticos através do modelo proposto que será validado através de dados experimentais.
Stress Corrosion Cracking (SCC), which consist in the initiation and propagation of cracks due to the combined attack of mechanical stresses and a corrosive environment is a potential danger for structures and components. Moreover, SCC can be explained by different mechanisms depending on the metal environmental pair, what makes difficult to create a generalized analytical approach to predict the crack behavior in SCC. Therefore, projects often use an over-conservative design criteria that disqualify a material susceptible to SCC without properly evaluate the influence of the stress fields that drive them. The aim of this work is to evaluate the effect of elastic-plastic stress in SCC. This mechanical approach assumes that all chemical effects involved in SCC problems can be appositely described and quantified by traditional material resistances to crack initiation and propagation at under specific environment. Aluminum bending specimens in Gallium environment are used to predict the effect of the residual stress induced by plastic deformation in the crack initiation under SCC conditions. Furthermore, a quantitative analysis based on the non-propagating crack behavior departing from notch tips are used to calculate the necessary stress to initiate and propagate SCC in AISI 4140 steel notched specimens under aqueous hydrogen sulfide environment. The non-propagating crack behavior and the maximum load supported by notched specimens are analyzed under linear elastic and elastic-plastic stress field through the proposed model that will be validated by experimental data.
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Iyer, Venkatramani S. "Effect of residual stress gradients in austenitic stainless steels on stress corrosion cracking." Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/42119.
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The effect of the residual stresses developed during simulated weld heat affected zone in
austenitic stainless steel specimen on the stress corrosion cracking susceptibility was studied.
Residual stresses was measured using X-ray diffraction technique. Boiling Magnesium
Chloride was used as corrosive environment. Compressive stresses developed in the HAZ of
the specimen and in regions away from the HAZ stress free values were obtained. The magnitude
of the stress gradient decreased as the peak temperature attained during simulated
welding decreased. Transgranular cracks were observed in the compressive stress gradient
region and time to cracking decreased with increasing stress gradient. Higher nickel content
alloys took longer to crack as opposed to lower nickel content alloys at approximately the
same stress gradient.
Master of Science
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Poirier, Patrick. "Effect of chronic stress on prefrontal cortical function." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86861.
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The prefrontal cortex (PFC) is a brain region thought to mediate cognitive functions such as working memory. Chronic stress has been shown to reduce working memory. In this thesis study, the effect of chronic stress on PFC functions was assessed in adult rats.First, contrary to previous evidences, chronic stress induces working memory performance alterations differentially in two populations of rats. One group displayed a decrease of performance only at 30 second delay, while the other had a decrease and increase at 0 and 30 seconds respectively.
Then, the effect of chronic stress on synaptic plasticity induction in the hippocampus-PFC network was investigated. High-frequency tetanic stimulation (HFS) of the dorsal hippocampus that induced long-term potentiation (LTP) in the prelimbic and infralimbic cortex in normal conditions was unable to induce LTP after chronic stress in the infralimbic cortex, whereas long-term depression (LTD) instead of LTP was induced in the prelimbic cortex.
Given that synaptic plasticity has been shown to depend on NMDA receptors in the PFC, NMDA subunit expressions before and after chronic stress was examined. There was a decrease of NR1 subunits expression in the prelimbic, but not infralimbic cortex. In contrast, the NR2A/NR2B ratio was increased in the infralimbic, but not prelimbic cortex. These results suggest that chronic stress disrupts PFC functions through dynamic modulation of distinct neural networks within the PFC.
Le cortex préfrontal (PFC) est une région du cerveau qui contrôle les fonctions cognitives comme la mémoire de travail. Dans cette thèse, l'effet du stress chronique sur des fonctions du PFC a été analysé chez des rats adultes.
Premièrement, les performances de la mémoire de travail ont été mesurées avant et après exposition au stress chronique. Nous avons constaté que le stress chronique induit des changements de performances de la mémoire de travail différemment selon deux populations de rats. Une des populations a démontré une diminution de performance seulement à 30 secondes de délai. Au contraire, l'autre a démontré une diminution de performance à 0 seconde et une amélioration de performance à 30 secondes.
En plus, nous avons évalué l'effet du stress chronique sur l'induction de la plasticité synaptique dans le réseau reliant l'hippocampe au PFC. Dans les conditions initiales, une stimulation tétanique à haute fréquence (HFS) dans l'hippocampe dorsal provoquait une potentialisation à long terme (LTP) dans le cortex prélimbique et infralimbique Or après exposition au stress chronique, une stimulation tétanique à haute fréquence n'a pas entraîné de potentialisation à long terme dans le cortex infralimbique. De plus, une exposition au stress chronique a provoqué l'apparition dans le cortex prélimbique d'une dépression à long terme (LTD) plutôt qu'une potentialisation à long terme.
Étant donné que la plasticité synaptique dépend des récepteurs de NMDA dans le PFC, nous avons examiné l'expression de sous-unité de NMDA avant et après exposition au stress chronique. En accord avec les changements synaptiques distincts de plasticité entre le cortex prélimbique et infralimbique après exposition au stress chronique, nous avons observé que l'expression de la sous-unité NR1 a diminué dans le prélimbique, mais non dans l'infralimbique. En revanche, le ratio de NR2A/NR2B a augmenté dans le cortex infralimbique, mais non dans le prélimbique. Ces résultats suggèrent que le stress chronique perturbe les fonctions du PFC par la modulation dynamique des réseaux distincts neurologiques dans le PFC.
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Barsoum, Imad. "The effect of stress state in ductile failure." Doctoral thesis, Stockholm : Hållfasthetslära, Kungliga Tekniska högskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4667.
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Bogart, Robert William. "The effect of stress on global cerebral ischemia." Connect to resource, 2008. http://hdl.handle.net/1811/32235.
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Yeh, Lestter. "The Effect of Stress Coping Techniques in Sports." Scholarship @ Claremont, 2016. http://scholarship.claremont.edu/cmc_theses/1240.
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The first part of this literature review goes over the biological and psychological aspects of stress. The cause of stress can be linked back to a primitive instinct known as “fight or flight.” The “fight or flight” instinct is triggered by several chemical reactions in the body starting from a signal from the amygdala to the sympathetic nervous system. Stress can also be categorized into internal and external stress. Further research links stress to sports. Many studies show that stress coping techniques such as meditation, self-talk, rituals, etc. are beneficial to athletes during competition. Suggested avenues of further research are to develop a standardized way to incorporate practicing stress coping techniques into a younger athlete’s routine, discover whether the same stress coping techniques can be used throughout all sports, and whether certain stress coping techniques will benefit people of different personality types equally. Keywords: Stress, Coping, Sports, Psychology, Athlete
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Picton, S. "The effect of heat-stress on tomato ripening." Thesis, University of Nottingham, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233614.
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Mathers, John F. "The effect of stress on golf putting performance." Thesis, University of Strathclyde, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431793.
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Kumsta, Caroline. "The effect of oxidative stress on C. elegans." kostenfrei, 2008. http://mediatum2.ub.tum.de/doc/678556/678556.pdf.
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Hoskin, Robert. "The effect of psychological stress on auditory perception." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/6193/.
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Psychological stress appears to precede instances of auditory hallucinations in those vulnerable to them. This suggests that psychological stress acts on the auditory perceptual system in such a way as to encourage the generation of false percepts. This thesis investigated the impact of psychological stress on the perception of emotionally neutral sounds with the aim of identifying a potential mechanism to explain the influence of stress on the occurrence of auditory hallucinations. Two interconnected hypotheses, arising from the theory that stress reduces attentional control and therefore the ability to inhibit distracting information, were tested. An auditory signal detection task was created to test whether stress would reduce the ability of the auditory-perceptual mechanism to accurately detect signals. Instead of reducing discrimination ability, stress was found to bias responding towards reporting a signal in highly anxious individuals. A number of passive oddball tasks were designed to test the hypothesis that stress would increase the distraction caused by emotionally neutral sounds. Once again this hypothesis was largely refuted, with stress appearing to reduce, rather than increase, the impact of distracting auditory information on task performance. On the basis of these findings a revised model of how stress may encourage auditory hallucinations was proposed. This model suggests that, through a strengthening of selective attention, stress may mal-adaptively bias auditory perception towards misinterpreting internal signals as external. Further research proposals, designed to test the predictions of this model, are suggested.
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Brattos, Alexandra. "The Effect of Stress Presentation Mode on Stress Acquisition Among Advanced Learners of Russian." BYU ScholarsArchive, 2012. https://scholarsarchive.byu.edu/etd/3140.
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The purpose of this research was to test the effect of stress presentation mode on stress acquisition of advanced learners of Russian. The study attempted to determine if advanced learners of Russian are able to place stress more correctly on words in specific texts after receiving various treatments or receiving no treatment. Participants were Brigham Young University students studying Russian as a second language at the third-year level or higher. They were randomly assigned into three groups: a group that received no treatment, a treatment group that read words with graphically marked stress, and a treatment group that heard texts read by a native speaker. All participants completed a pretest, a treatment (in the second and third groups), and a posttest. The pretest and the posttest consisted of a reading task: the participants read 12 sentences taken from 12 different texts. The same words from the texts were used in the treatment to expose the participants to the sentences again in order to determine if the treatment made a difference in the acquisition of correct stress. The treatment was different for each group. Group 1 (A) read texts marked with stress, Group 2 (B) read the same texts but without stress marked; rather, they heard a native speaker of Russian read the texts on a recording, and Group 3 (C) read the same texts but without stress marked graphically or hearing a native speaker. The results of the research reject the hypothesis that aural presentation of stress as opposed to a visual only presentation leads to improved acquisition of stress. However, based on the analyses of the data, overall findings rendered some interesting and unexpected results and observations. First, although the treatment for group A appears to be more effective than that for groups B and C, all groups showed improvement after completing the treatment. This strongly suggests that reading, whatever form it takes, can be a useful tool in facilitating control of stress. Second, group A had more participants that fell into the "fast" reading category, and fast readers scored significantly higher than slow or medium speed readers. This suggests that the faster one reads the better one controls stress, or the better one controls stress the faster one reads.
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Followell, Timothy B. "Effect of Dental Treatment on Parental Stress as Measured by the Parenting Stress Index." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1276567183.
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Cesaretti, Juan Manuel. "Mechanical stress and stress compensation in Hall sensors." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/28202.
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Eakes, Donald Joseph. "Moisture stress conditioning, potassium nutrition, and tolerance of Salvia splendens 'Bonfire' to moisture stress." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54350.
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The objective of this study was to determine the leaf water relations, gas exchange, and growth of the bedding plant salvia Salvia splendens 'Bonfire‘ as influenced by moisture stress conditioning (MSC - exposing plants to 4 sublethal dry-down cycles) and potassium (K) nutrition. Plants were fertilized with one of six K rates: 25, 75, 150, 300, 450, and 600 ppm as KCl in experiment one. Seven weeks after seeding plants were subjected to MSC. MSC and increasing K rate resulted in osmotic adjustment and increased cellular turgor potentials. Foliar K content increased as osmotic potentials decreased due to treatment. Although there was no interaction, MSC and high K rates both reduced transpiration (E), leaf conductance (g₁), and daily gravimetric water loss during well watered conditions. Greatest shoot dry weight occurred for plants grown with 300 ppm K and no-MSC.
Gas exchange of salvia as influenced by MSC during the onset of moisture stress was determined in experiment two. On day one following final irrigation, MSC plants had lower mid-day E, g₁, hourly gravimetric water loss per unit leaf area, and net photosynthesis (Pn) compared to controls, despite no differences in leaf water potential (ψ₁). Percentage of stomatal inhibition of Pn (SI) was greater for MSC plants than controls with no differences in mesophyllic resistance to CO₂ (rm). On day two, MSC plants had greater Pn, E, g₁, and hourly gravimetric water loss per unit leaf area, while SI and rm were lower than controls. MSC plants maintained positive Pn rates and turgor to lower ψ₁ than control plants. Water use efficiency (WUE) estimates for MSC plants were greater than for controls.
Salvia plants were fertilized with 75, 300, or 600 ppm K to determine the influence of K rate on gas exchange during the onset of moisture stress in a third experiment. On day one following final irrigation, plants grown with K rates of 300 and 600 ppm had lower E, g₁, hourly gravimetric water loss per unit leaf area, and Pn compared to 75 ppm K plants. On day two, 600 ppm K plants had greater Pn, E, and g₁ as the experiment was terminated compared to plants grown with 75 ppm K, although ψ₁ was similar. Potassium rate had little affect on WUE.Ph. D.
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Cummins, Robert A. "The effect of organizational structure and demographics on administrative stress." Theological Research Exchange Network (TREN), 1987. http://www.tren.com.
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Sun, Hong. "The effect of hydrodynamic stress on plant embryo development." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33945.
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The effect of steady shear stress on somatic embryos were investigated in a flow chamber and evaluated at different time intervals using microscopy technique. The development of meristematic cell clusters, i.e. the immature embryos, into a polarized somatic embryo, and the effect on the localization of the suspensor cells that form during development of the immature embryos, were studied as a function of shear stresses. With the distribution and growth rate of the meristematic and suspensor cells, the effect of stress on the embryo development was established. Furthermore, the effect of shear stress on the cells at molecular level, the reaction of integrin-like proteins, the production of reactive oxygen species and the pore size of the cell walls involved in the shear stress responses, were investigated with molecular techniques.
In general, shear stress inhibits meristematic cells growth. Meristematic cells grow fastest at shear rate of 86 s-1 among all the tested shear stress conditions. By combining the results of meristematic cells growth and suspensor cells formation, it suggests that there is a critical shear rate between 86 and 140 s-1, at which no suspensor cells form. The unidirectional flow with different shear stresses helps the polarized growth and the unidirectional alignment of suspensor cells. Reactive oxygen species and integrin-like protein are detected in the stressed cells as cellular responses to shear stresses. By monitoring the pore size and uptake time of cells to macromolecules with solute-exclusive experiments, it suggests that the stressed cells expedite the response to plasmolyzing components that are used to induce maturation treatment thus affect the response to maturation stimuli.
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Keeley, Maureen Patricia 1961. "THE EFFECT OF STRESS ON THE DECODER'S COMMUNICATION CHANNELS." Thesis, The University of Arizona, 1987. http://hdl.handle.net/10150/276499.
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This thesis investigated the interaction of stress and decoding accuracy through the vocalic and facial kinesic channels and with regard to gender. Stress (high and low) was created for 372 undergraduate students using the Stroop Color-Word Test. Overall, results did not show that an increase in stress led to a decrease in decoding accuracy. However, the findings did suggest that stress was impacting on the decoding process. The researcher uncovered a main effect for channel such that the facial kinesic channel was the most accurate for decoding emotions. In addition, an ordinal interaction was found during the first time period which showed that stress was differentially affecting the four groups (kinesic, high and low stress; vocalic, high and low stress). Males and females were affected in a similar manner by stress, with females being consistently more accurate decoders than males regardless of the amount of stress or channel used.
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Crowe, P. J. "The effect of diet and stress on substrate metabolism." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379881.
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Chan, Wan-Kan. "A study of the thermoelastic effect for stress analysis." Thesis, University of Manchester, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383253.
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Denison, Tracy Adam. "The effect of fluid shear stress on growth plate." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29603.
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Thesis (Ph.D)--Biomedical Engineering, Georgia Institute of Technology, 2009.Committee Chair: Boyan, Barbara; Committee Co-Chair: Schwartz, Zvi; Committee Member: Bonewald, Lynda; Committee Member: Jo, Hanjoong; Committee Member: Sambanis, Athanassios. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Su, Dan. "Microcrack damage and its effect on stress wave propagation." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 114 p, 2009. http://proquest.umi.com/pqdweb?did=1654487641&sid=6&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Johnson, Bobbie. "Effect of stress and diapause in two Calliphoridae species." Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4200/.
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Cultures of two Dipteran flies (Calliphora vicina (R-D) and C. vomitoria (L.)) were established to answer questions in regards to responses to thermal and desiccation stress, effects of diapause and the mechanisms which underpin diapause. The findings are divided in to two sections. Unequivocal new findings – Calliphora vomitoria were seen to depend on water being present in culture medium for increased survival. Furthermore, C. vomitoria were found to have lower desiccation resistance than C. vicina. Larvae of C. vicina and C. vomitoria showed different cold tolerance strategies, with C. vicina being freeze-avoiding and C. vomitoria ‘partially’ freeze-tolerant. Metabolomics, using \(^1\)H-NMR, revealed that diapause and non-diapause had distinct metabolic profiles. Diapause larvae were seen to reduce energy synthesis from the Krebs cycle and increase glycolysis. Calliphora vicina and C. vomitoria also exhibited different diapause phenotypes; C. vicina entered a maternally regulated facultative diapause as an L3 larvae, Calliphora vomitoria had a less distinct diapause, with maternal conditions having little effect. Speculative new findings - Despite the above differences C. vicina and C. vomitoria were able to produce a viable cross, though field fresh C. vomitoria were not used, as such it cannot be confirmed if this could occur in the wild. Increased temperatures due to climate change may affect both phenology and survival of insects; C. vicina was seen to have a delayed induction to diapause and a reduction in the proportion entering diapause. Diapause conferred increased cold tolerance; therefore those insects that overwinter not in diapause may suffer increased mortality.
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Palanki, Zoltan. "Effect of the applied stress on shape memory alloys." Besançon, 2009. http://www.theses.fr/2009BESA2002.
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Dans cette thèse, deux modèles ont été utilisés. Celui développé à Debrecen (Hongrie) a permis de calcul les termes d'énergie non-chimique au début et à la fin de transformation martensitique. Nonobstant, non seulement ces termes sont indispensables mais la connaissance de la dépendance des termes dissipatifs élastiques à la fraction de martensite transformée est, elle aussi, importante. En conclusion, une extension de modèle s'est avérée nécessaire. Ce nouveau modèle a été utilisé afin de rationaliser les mesures effectuée sur des alliages à mémoire de forme CuAINi poly et monocristallins. Les résultats de mesures sur l'échantillon monocristallin n'ont pu être interprétés que si le concept de deux types de phase martensitique est introduit. Le modèle de Besançon (France), développé pour expliquer la transformation martensitique, introduit ce deux martensites différentes (la martensite auto-accommodante et la martensite induite par la contrainte). 0n verra que cette partition n'a aucun sens crystallographique mais est simplement utile dans une approche phénoménologique. Après qu'un lien ait été établie entre ces deux modèles et que deux phase martensitiques aient été prises en compte dans le modèle de Debrecen, la détermination des paramètre nécessaires aux simulations devient possible, et la comparaison a pu être réalisée entre les boucles hystérésis mesurées et calculéesIn this thesis two models will be concerned. The one developed earlier in Debrecen enabled to calculate the non-chemical energy terms at the start and at the end of martensitic transformation. Nevertheless not only theses points are relevant but the knowledge of the dependence of the dissipative and elastic terms on the transformed martensitic fraction in the whole transformation range is important too. Consequently an extension of the model was needed. This new model was used to evaluate the data measured on polycrystalline an single crystalline CuAINi shape memory alloys. The results of the measurements on single crystalline samples could be explained only if two types of martensitic phases were taken into account. Indeed the Besançon model developed for simulation of the martensitic transformation counts with two different martensitic phases too, namely temperature and stress induced ones. After finding the connection between these two models and took them also into account in the Debrecen-model the determination of the input parameters for the simulations became possible and comparison between the measured and calculated hysteresis loops had been made
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Hollie, Alfred Henry. "Effect of Hot Spot Policing on Reducing Officer Stress." ScholarWorks, 2019. https://scholarworks.waldenu.edu/dissertations/7390.
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Police officers endure various threats ranging from verbal abuse to physical attacks, which can escalate and lead to police officer stress. Despite the abundant research exploring the relationship between high-stress occupations and environmental health, adequate exploration of the relationship between officer stress and hot spot policing (HSP; area with an above-average level of crime) has yet to occur. The purpose of this correlational study was to use Cohen and McKay's conceptualization of the stress-buffering hypothesis to explore whether HSP mitigates the negative impact of job stress, leading to improved officer performance and ultimately improved relationships between the police and communities as well as lower crime rates. Posting of a SurveyMonkey link in law enforcement only, social-media communities (with administrator permission) facilitated data collection for the 151 respondents. Findings indicated that the overall regression model was significant; however, the simple correlation between HSP and officer stress (.118) indicated that HSP alone does not account for unique variance (there was a value of .014 or 1.4% of the variation in officer stress). The social change implications of this study include recommendations to police department administrations to continue to explore efforts to reduce officer stress, which could lead to improved officer performance and police and community relationships.
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Crisp, William A. "Combat Posttraumatic Stress Disorder: Effect of Intelligence on Symptomatology." Thesis, University of North Texas, 2004. https://digital.library.unt.edu/ark:/67531/metadc4527/.
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The objective of this study was to examine the relations between Posttraumatic Stress Disorder symptomatology and intelligence. Thirty American combat veterans of the Vietnam War, diagnosed with chronic PTSD, were given a psychodiagnostic structured interview. Participants were assessed for Intelligence Quotient as well as the veracity of their self report. The study found that there were significant differences in how participants experienced their PTSD symptoms that were correlated with intelligence. The higher IQ participants reported more frequent and intense guilt related symptoms as well as more intense intrusive recollections. The lower IQ participants experienced more frequent startle responses, more intense problems related to falling or remaining asleep and more frequent affective symptoms related to emotional numbing. Psychologists could use these differences in how PTSD is experienced in treatment planning. It may be useful for therapy to address sleep disturbances and affective numbing in lower IQ individuals. Therapy for higher IQ individuals may be more useful if it addresses feelings of guilt and intrusive recollections.
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Didriksen, Nancy A. (Nancy Andrews). "The Effect of Examination Stress on Phagocytic Immune Functioning." Thesis, North Texas State University, 1985. https://digital.library.unt.edu/ark:/67531/metadc500983/.
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The purpose of this study was to determine whether psychological stress, specifically examination stress, would decrease immune system functioning. Twenty-five first-year master's and doctoral students who volunteered to participate in the study were psychologically and immunologically assessed during two high- and two low-stress periods. Immunological assessments included a white blood cell differential count and nitroblue tetrazolium test (NBT) to measure neutrophil functioning. Psychological instruments administered at each assessment period included Clinical Analysis Questionnaire (CAQ), Bender Gestalt Test, State- Trait Anxiety Inventory (STAI) and a Brief Stress Questionnaire. Stepwise discriminant function analysis of data revealed five variables which contributed significantly to change under stress and yielded an average canonical correlation of .79 (p < .002) providing evidence of support for the hypothesis that increased psychological stress will alter immune functioning and heighten psychological responses.
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Kissane, Abby. "The Effect of Oxidative Stress on Myometrial miRNA Expression." Scholarship @ Claremont, 2017. http://scholarship.claremont.edu/scripps_theses/1072.
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Approximately 1 in 11 births in the United States are preterm (gestation). Within the United States, there are huge racial disparities for risk of preterm birth, an issue understudied and rarely addressed by research in the field. There is a wealth of biological knowledge surrounding pregnancy and labor, but causes for preterm birth are poorly understood. A genetic factor that has been shown to play a key role in many biological processes crucial to a healthy pregnancy and timely labor is microRNA (miRNA). MiRNA have an active role in the regulation of various tissues, especially developing tissues like those found in the placenta and uterus. Additionally, oxidative stress has been shown essential to placental development and the initiation of labor. Here, a study is proposed that aims to address the effect of oxidative stress on myometrial miRNA expression, specifically the miR-200 family and miR-199/214 cluster. This work also underscores the importance of addressing racial disparities with regards to preterm labor during research, while bringing up ethical considerations for conducting such research. The thesis will conclude with an outline of the many considerations vital for discussing the research and analysis of preterm birth disparities using a feminist, antiracist, queer self-reflexive analysis.
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Marckwordt, Michelle. "Effect of Early Traumatic Experience on Current Stress Levels." Thesis, California State University, Long Beach, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10690957.
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Past findings regarding the effects of early trauma exposure have been contradictory, showing it to produce both resilience and vulnerability to future stressors. This may be explained by restricted samples, the use of inadequate measures of stress, and/or a failure to consider the possibility of curvilinear relationships. The present study sought to improve on past methodologies, sampling from a community population, utilizing a theory-consistent and well-validated measure of stress, and conducting quadratic regression analyses. Adult participants (N = 255) were recruited from community sites, where they completed the Lifetime Trauma Checklist, the Stress Overload Scale, and a demographic questionnaire. Analyses confirmed a curvilinear relationship between early trauma and stress overload, but not in the expected direction. Both zero- and low-exposure groups had lower levels of current stress overload than the moderate- and high-exposure group, but stress overload scores began to show a decline among the highest in the high-exposure group. The same relationship was found for one of the components of stress overload, personal vulnerability, but not the other, event load. The implications of this differential, possible explanations for the curvilinear result, and the import of these findings for both theory and practice are discussed.
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MacCombe, Diane Martha Elizabeth. "The effect of mild acid stress on environmental microorganisms." Thesis, Queen's University Belfast, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491881.
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The requirement to reduce biomass production & enhance polyphosphate production during the wastewater treatment process is necessary to ensure the process is environmentally sound & cost effective. The effect of mildly acidic pH (pH6.0) on . the biomass formation & polyphosphate production by a range ofenvironmental microorganisms was investigated, using activated sludge from a trial wastewater treatment plant & a range ofenvironmental isolates. Activated sludge obtained from a treatment plant operating at pH6.0, produced lower levels of biomass alongside a higher level ofphosphate removal & higher rates ofrespiration & substrate utilisation, compared to operation ofthe same plant at higher operational pH levels. Seven pure culture isolates were also characterised in terms of their phosphate removal & biomass yields over a range ofpH values (5-.5 to 7.5). Isolates could be identified as members ofone Qfthe following: (1) demonstrate reduced biomass yields & accumulate more polyphosphate at an acidic pH, e.g. Erwinia carotovora subsp. atroseptica, (2) exhibit reduced biomass yields & polyphosphate accumulation at acidic pH e.g. Pseudomonf:ls aeruginosa PAOl, and (3) display similar or higher biomass yields at acidic pH & accumulate higher levels ofpolyphosphate at these acidic pH levels, e.g. Burkholderia cepacia AM19. Three microorganisms were studied further in continuous culture at pH6.0. E. carotovora displayed lower levels of biomass yield coupled with higher substrate utilisation rates, ATP formation rates & total intracellular P levels. B. cepacia AM19 & P. aeruginosa PAOl, in contrast displayed similar levels ofbiomass production, P removal & substrate utilisation rates. The response by E. carotovorG&activated sludge to acidic pH would suggest an increase in maintenance energy at acidic pH, caused by an increased rate ofproton pumping in order to maintain a constant intracellular pH with polyphosphate playing a protective role at acidic pH.
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Hicks, Trevor. "Standardised stress management training : does it have an effect?" Thesis, King's College London (University of London), 2015. http://kclpure.kcl.ac.uk/portal/en/theses/standardised-stress-management-training-does-it-have-an-effect(cddc9014-2eca-4a21-9ac7-d0d44f4ea86f).html.
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Stress Management Training (SMT) may be an effective treatment for patients diagnosed with anxiety and depression. An SMT package has been given to active regular military personnel diagnosed with anxiety and depression under the care of the Department of Community Mental Health (DCMH), RAF Brize Norton. The SMT was not standardised and provided psycho-education and generic anxiety management. This thesis describes attendees (n=90) of the unstandardised SMT. The unstandardised SMT was then standardised and its effectiveness was investigated by means of a Randomised Controlled Trial (RCT). The RCT compared participants (n=53) who received standardised SMT to those on the waiting list (control group) (n=45). Outcome measures used in the RCT were the General Health Questionnaire (GHQ-28), Beck Depression Inventory (BDI-II), Beck Anxiety Inventory (BAI) and Clinical Global Impression (CGI). The results of the unstandardised SMT study showed that most attendees (91%) were diagnosed with adjustment disorders prior to the study. Most attendees (57%) met the threshold, as determined by the BDI-II, for a possible depressive disorder by the time they received the unstandardised SMT. This finding was replicated in the RCT where most participants (94%) were diagnosed with adjustment disorders prior to the study but most participants (81%) exceeded the threshold, as determined by the BDI-II, for a possible depressive disorder by the time they received the standardised SMT. The results of the RCT showed that standardised SMT had a short term beneficial effect at six weeks in participants with high scores on the BDI-II but not in participants with high scores on the BAI. This effect was no longer present at 12 weeks. This thesis does not support the continued use of SMT as a tertiary stress management intervention within the military or the wider adoption of standardised SMT to treat regular, active military personnel with diagnoses of anxiety or depressive disorders. This thesis recommends that the military may wish to test the effectiveness of providing different stress management interventions as a secondary stress management intervention instead.
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Hibbert, George. "Hyperventilation in panic : cause or effect?" Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235982.
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Yang, Di. "Cyclic stress effect on stress corrosion cracking of duplex stainless steel in chloride and caustic solutions." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42811.
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Duplex stainless steel (DSS) is a dual-phase material with approximately equal volume amount of austenite and ferrite. It has both great mechanical properties (good ductility and high tensile/fatigue strength) and excellent corrosion resistance due to the mixture of the two phases.
Cyclic loadings with high stress level and low frequency are experienced by many structures. However, the existing study on corrosion fatigue (CF) study of various metallic materials has mainly concentrated on relatively high frequency range. No systematic study has been done to understand the ultra-low frequency (10-5 Hz) cyclic loading effect on stress corrosion cracking (SCC) of DSSs.
In this study, the ultra-low frequency cyclic loading effect on SCC of DSS 2205 was studied in acidified sodium chloride and caustic white liquor (WL) solutions. The research work focused on the environmental effect on SCC of DSS 2205, the cyclic stress effect on strain accumulation behavior of DSS 2205, and the combined environmental and cyclic stress effect on the stress corrosion crack initiation of DSS 2205 in the above environments.
Potentiodynamic polarization tests were performed to investigate the electrochemical behavior of DSS 2205 in acidic NaCl solution. Series of slow strain rate tests (SSRTs) at different applied potential values were conducted to reveal the optimum applied potential value for SCC to happen. Room temperature static and cyclic creep tests were performed in air to illustrate the strain accumulation effect of cyclic stresses. Test results showed that cyclic loading could enhance strain accumulation in DSS 2205 compared to static loading. Moreover, the strain accumulation behavior of DSS 2205 was found to be controlled by the two phases of DSS 2205 with different crystal structures. The B.C.C. ferrite phase enhanced strain accumulation due to extensive cross-slips of the dislocations, whereas the F.C.C. austenite phase resisted strain accumulation due to cyclic strain hardening. Cyclic SSRTs were performed under the conditions that SCC occurs in sodium chloride and WL solutions. Test results show that cyclic stress facilitated crack initiations in DSS 2205. Stress corrosion cracks initiated from the intermetallic precipitates in acidic chloride environment, and the cracks initiated from austenite phase in WL environment. Cold-working has been found to retard the crack initiations induced by cyclic stresses.
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Chu, Angel On Kei 1975. "The effect of stress on nuclear transport and nuclear organization /." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82846.
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Stress is implicated in various diseases such as cancer, ischemia, and inflammatory diseases. Many different forms of stress may result in impaired physiological functions. Therefore, it is important to understand the mechanisms by which cells compensate and adapt to stress. Defining the changes that occur in nuclear structure and transport between the nucleus and cytoplasm in a cell are of specific interest and will contribute significantly to our understanding of stress response.I have demonstrated that classical nuclear import is inhibited by oxidative stress in living HeLa cells as a result of relocalization and degradation of nuclear factors important for the nuclear transport apparatus. Specifically, hydrogen peroxide redistributes Ran, the GTPase important for the directionality of transport, importin-beta, a subunit of the nuclear import receptor, and Nup153, a component of the nuclear pore complex. Moreover, the stress-induced relocalization and degradation does not rely on the activation of MAPK pathways.
Heat shock proteins have established roles in normal cellular homeostasis as well as in stress response. In unstressed conditions, proteins of the hsp70/hsc70 family shuttle between the nucleus and the cytoplasm. Upon stress, cytoplasmic hsp70s/hsc70s accumulate in the nucleus. I have further characterized the effect of stress on hsc70s localization in HeLa cells. Heat-induced nuclear concentration of hsc70s depends on cell density. Moreover, protein phosphorylation negatively regulates hsc70 nuclear accumulation in response to heat. During recovery from heat stress hsc70s redistribute as they are exported into the cytoplasm. Hsc70 export is temperature- and energy-dependent, but is independent of the Crm1/exportin1-mediated pathway. Moreover, export of hsc70 is inhibited by depolymerization of nuclear actin.
In higher eukaryotes, lamins and other lamina-associated proteins provide links between the nuclear envelope and chromatin. The protein circumferin is located at the nuclear periphery in yeast and higher eukaryotes. I have demonstrated that stress relocalizes circumferin, which is released from the nuclear periphery into the nucleoplasm upon heat shock. These studies are the first to demonstrate that nuclear envelope organization in yeast and mammalian cells is modulated by stress.
Taken together, these results indicate that both nuclear transport and nuclear organization are affected by stress.
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Momayezzadeh, Mohammed. "Stress memory measurement using the Kaiser effect of acoustic emission." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41156.
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This thesis investigates in detail the stress memory of hard rocks under uniaxial compressive conditions as a time-saving and inexpensive alternative to traditional in-situ stress measurement techniques. Extensive laboratory experiments are carried out to assess the influence of parameters such as transducer/amplifier frequency response, signal definition parameters, stress rate, strain rate, specimen size, stress level, delay time, temperature, water content, confining pressure, and directional loading on the Kaiser Effect of Stanstead granite and other rock types. Based on these findings and a new data processing techniques developed for estimating the previous stress level, a testing procedure is suggested and used to determine in-situ stresses from core samples with respect to their drilling orientations. In two case studies, the estimated stresses using the Kaiser Effect phenomenon are in good agreement with values obtained from conventional techniques while in the third study, no stress value was obtained due to the inability of the rock type to generate acoustic emissions. The results of this investigation show that the Kaiser Effect could become an economical method of stress measurement in hard and isotropic rock types.
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Primprao, Disayavanish Strand Kenneth H. Padavil George. "The effect of Buddhist insight meditation on stress and anxiety." Normal, Ill. Illinois State University, 1994. http://wwwlib.umi.com/cr/ilstu/fullcit?p9510422.
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Thesis (Ph. D.)--Illinois State University, 1994.Title from title page screen, viewed March 24, 2006. Dissertation Committee: Kenneth H. Strand, George Padavil (co-chairs), Larry D. Kennedy, John R. McCarthy. Includes bibliographical references (leaves 132-142) and abstract. Also available in print.
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Louchnikov, Vadim. "A numerical investigation into the stress memory effect in rocks." Click here to access, 2004. http://hdl.handle.net/2440/37740.
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Reliable and inexpensive methods of in-situ stress measurement have been sought for more than 40 years. A number of non-destructive core-based methods of in-situ stress determination are currently available, among which Deformation Rate Analysis ' DRA ' and Acoustic Emissions ' AE ' method have the most promising potential due to their ability to measure stress as opposed to strain, which is measured by strain recovery techniques. The DRA and AE method are similar in their utilisation of a phenomenon termed Kaiser effect in the case of AE and deformation memory effect in the case of DRA. The KE/DME is defined as a recollection of a maximum stress a rock core had been subjected prior to its retrieval from the in-situ environment. The physical nature of this phenomenon has not however been universally established. In this study, interaction of microcracks as the most probable cause of the KE/DME, was investigated. To reproduce the damage that occurs to rock at the micro level, a discrete element modelling code was required, which enabled dynamic failure propagation to be modelled. Commercially available code PFC [ superscript 2D ] was found to be suitable for this purpose due to its ability to explicitly model mechanical damage in rocks. The numerical model was based on a real prototype - a sandstone rock core, which had also been previously subjected to the DRA. Although the bulk of the numerical tests were conducted on intact rock models, it was found that changes in the lithology and introduction of discontinuities did not have significant effect on the DME. Influence of the confining stress on the DME was confirmed. It was assumed that only the highest historical stress could be determined reliably using the DRA technique. The ability of the numerical model to reproduce the DME was validated. The link between the DME and development of microcracks was established. The results of the study encourage further use of the code for understanding the micromechanical behaviour of rocks under loading.Thesis (M.Eng.Sc.)--Australian School of Petroleum, 2004.
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Sun, Yitao. "Effect of stress on silicon oxynitride optical waveguides and devices." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ62856.pdf.
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Basoah, Afua. "The effect of oxidative stress on protein modification and degradation." Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400552.
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Banfield-Zanin, Jennifer A. "The effect of drought stress on the green spruce aphid." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/18966.
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The green spruce aphid, Elatobium abietinum (Walker) (Hemiptera: Aphididae), is the most important defoliating pest of Sitka spruce, Picea sitchensis (Bong.) Carr., in the U.K. Currently, populations of this aphid are limited by freezing periods in the winter, while interactions between climate and other factors regulate population dynamics. Climate change in the U.K. is predicted to result in: (1) warmer winters, improving overwinter survival by aphid populations, and (2) an increase in hot and dry summers, likely to place Sitka spruce under drought stress. These could promote aphid densities and increased damage to the trees, resulting in losses to plant growth and productivity. Few studies have been conducted on the effect of drought stress on arboreal herbivores. This project sought to explore the effects of different intensities of spring-summer drought stress on E. abietinum on Sitka spruce. Populations and their effects on their host plant, in terms of needle retention and impact on tree growth, were observed in a semi-field nursery setting. The performance of individual aphids was also observed under controlled conditions at intervals following bud-burst in spring, and again in autumn. Finally, a study was conducted on the consumption rates of specialist and generalist Coccinellid predators feeding on aphids reared under differing drought intensities. Elatobium abietinum exhibited an overall positive response to moderate intermittent drought stress, while severe stress was typically detrimental. When considered with aphid size, Coccinellid predator consumption rates reflected these findings. Changes to damage levels on Sitka spruce can therefore be expected under drought stress; increases are likely under moderate intermittent stress, though the nature of changes under severe stress levels remain unclear. The results revealed complex interactions between drought stress, E. abietinum and Sitka spruce. Given the potential impact of the aphid, it is important to understand the possible responses under climate change.
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Yake, Melissa L. "The effect of stress on eating practices among university faculty." Virtual Press, 2006. http://liblink.bsu.edu/uhtbin/catkey/1339600.
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The purpose of this study was to examine the relationship between comfort food preferences of college faculty when under normal (non-stressful) and stressful conditions. Thirty-four percent (n=63) of the participants were males and 66 percent (n=121) were females. Sixty-seven percent (n=123) experienced a change in appetite when stressed, with 69 percent (n=85) experiencing an increase and 31 percent (n=38) experiencing a decrease in appetite. Participants chose a significantly wider variety of foods when under stressful conditions for both sweet (p=<.001) and salty/crunchy food categories (p=.004). High restrained eaters chose significantly more types of sweet foods (p=.031) and beverages (p=.020) than low restrained eaters when comparing stressful and normal conditions. These findings suggest the majority of adults may experience changes in appetite with stress, specifically an increased appetite, and may choose more types of sweet and salty/crunchy foods. An individual's restraint level, gender, and age may also play a role in comfort food choice.Department of Family and Consumer Sciences
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West, Melanie Jane. "The effect of oxidative stress on ageing in drosophila melanogaster." Thesis, University College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412580.
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