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PREDICTING DISEASE INCIDENCE DUE TO CONTAMINATED INTRUSION IN A WATER DISTRIBUTION SYSTEMCHANDRASEKARAN, LATHA 02 October 2006 (has links)
No description available.
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Graduate Survival as an Outcome-Based Approach to Business Incubator Evaluation: A Case Study of the Hamilton County Business CenterVerba, Alison M. 26 September 2011 (has links)
No description available.
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Experimental Evaluation of Bone Drilling using Ultrashort Pulsed Laser AblationEmigh, Brent J. 10 1900 (has links)
<p>Mechanical oscillating drills and saws are used in orthopaedic surgery to cut bone and develop screw-holes; however, their use causes friction resulting in significant thermal damage. Ultrashort pulsed lasers appear well-suited to replace traditional tools as they have the ability to efficiently remove bone tissue while causing only minimal collateral damage. Laser ablation also has the added advantages of: (i) no mechanical vibration; (ii) minimal invasiveness; and (iii) small focus spot size. In this thesis work, we experimentally investigated a few key aspects of ultrashort laser ablation of bone tissue.</p> <p>The ablation threshold of unaltered bone was measured using the <em>D</em><sup>2 </sup>technique and found to range from 1.66 J/cm<sup>2 </sup>± 0.87 J/cm<sup>2</sup> to 2.37 J/cm<sup>2 </sup>± 0.78 J/cm<sup>2</sup> depending on incident pulse number. The reduction in ablation threshold with pulse number was an indication of an incubation effect. Using a power law model, the incubation coefficient, ζ, was measured to be 0.89 ± 0.03.</p> <p>The effect of specific laser parameters and drilling protocols on ablation efficiency was also characterized. For ultrashort pulses (≤10 ps), the removal rate was found to be inversely related to the pulse duration; however, irradiation with 5-10 ps pulses were also shown to result in significant tissue removal. With a pulse repetition rate of 1 kHz, the removal rate was observed to be highest when ablating with 50-100 pulses per spot.</p> <p>Larger volumes (>1 mm<sup>3</sup>) of bone tissue were removed using laser scanning procedures. A series of scanned concentric circles produced a structure ~2.4 mm deep; however, ablated side-lobes were present at oblique angles to the incident beam. A two-layer structure subsequently produced no side-lobes. The ablative precision in trabecular bone was observed to be less than cortical bone. Using mimicked Nd:YAG laser parameters, cylindrical drilling produced craters significantly less deep than those achieved with a typical Ti:Sapphire configuration. The ability to drill large-scale holes using low average pulse energies and optimized scanning procedures will alleviate the stringent requirements for optical components in clinical practice.</p> / Master of Science (MSc)
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Effect of probiotics or high incubation temperature on gene expression and cell organization of the small intestine and yolk sac of chicksJia, Meiting 30 November 2021 (has links)
The small intestine and yolk sac (YS) are important organs for nutrient absorption and innate immunity in chickens during the post-hatch or prehatch periods. These organs share a similar structure of epithelial cell-lined villi with tight junctions between adjacent cells. Probiotics have been reported to improve chicken growth performance and gut health including promotion of intestinal morphology. However, there are few studies that show the effect of probiotics on ontogeny of intestinal epithelial cells and antimicrobial peptides, or intestinal integrity in young healthy chicks. Heat stress during incubation was shown to increase mortality and decrease hatchability of chicks, while no studies have investigated the effect of heat stress on the integrity of the YS, which might be related to hatching performance. There were four studies conducted in this research: 1) a comparison of the effect of two probiotics on the ontogeny of small intestinal epithelial cells in young chicks; 2) the effect of two probiotics on mRNA abundance of tight junction proteins in the small intestine of young chicks; 3) the effect of high incubation temperature on mRNA abundance of tight junction proteins in the YS of broiler embryos; and 4) comparison of avian defense peptide mRNA abundance in the YS of broilers and layers. In study 1, Probiotics transiently decreased body weight gain (BWG) from day 2 to day 4, but did not affect body weight (BW) from day 2 to day 8, and small intestinal weight and intestinal morphology from day 2 to day 6. Probiotics did not affect marker gene expression of intestinal stem cells (Olfm4) and goblet cells (Muc2) in all small intestinal segments, but did increase expression of a marker gene of proliferating cells (Ki67), and decreased an antimicrobial peptide (liver-enriched antimicrobial peptide 2, LEAP2) in the jejunum at day 4. Probiotic 1 decreased PepT1, a marker of enterocytes in the duodenum at day 4. These results suggest that probiotics did not improve growth performance and intestinal morphology in young healthy chicks, but temporarily promoted intestinal epithelial cell proliferation and decreased LEAP2 antimicrobial peptide expression in the jejunum. In situ hybridization (ISH) showed that Ki67+ proliferating cells were mainly located in the crypt region and the blood vessels of villi. In study 2, Probiotic supplementation to newly hatched chicks for less than one week did not affect mRNA abundance of the tight junction proteins in the small intestine. Occludin (OCLN) mRNA, which was detected by ISH to be expressed in intestinal epithelial cells in both the villus and crypt regions, was greater in the duodenum of female chicks than males. In study 3, high incubation temperature starting from embryonic day 12 (E12) affected mRNA abundance of the tight junction proteins in the YS, including increased zonula occluden 1 (ZO1) at E13, increased junctional adhesion molecule A (JAMA) and heat shock protein 90 (HSP90) at E17, but decreased tight junction protein JAMA at E19 and OCLN at day of hatch (DOH). These results showed that the YS tight junction proteins were increased by short term heat exposure but decreased by long term heat exposure. In study 4, the expression of avian β defensin 10 (AvBD10), CATHs and toll-like receptors in the YS was examined. Toll-like receptors were highly expressed in the YS at early incubation stages (E7), while CATHs showed a peak expression from E9 to E13, which was similar to the expression pattern of AvBD10. CATHs and AvBD10 mRNA temporal expression patterns were similar in broilers and layers, while their expression levels were different. Layers, especially brown layers, had greater mRNA abundance for antimicrobial peptides such as AvBD10, CATH1, and CATH2 in the YS. These results demonstrate that the antimicrobial peptide temporal expression patterns in the YS are not affected by breed, but their expression levels are affected by breed. In summary, the small intestine and the YS are essential for nutrient uptake, innate immunity, and maintenance of integrity. The ontogeny of intestinal epithelial cells, such as proliferating cells can be modulated by probiotic supplementation. Similar to the small intestine, the YS can also express tight junction proteins, which can be affected by high incubation temperature. Antimicrobial peptide expression in the intestine of healthy young chicks is also transiently decreased by probiotic supplements. Avian defensin and cathelicidin expression patterns in the YS were not affected by breed. / Doctor of Philosophy / The small intestine and yolk sac are important organs for nutrient absorption in hatched chicks or embryonic chicks. These organs also serve as a barrier to prevent pathogens from entering the blood circulation. Intestinal epithelial cells along the villi renew rapidly by proliferation and differentiation. In this research, probiotics which are also known as direct fed microbials temporarily increased expression of the proliferating cell marker Ki67 in the jejunum of healthy young chicks, which suggests that probiotics promote intestinal epithelial cell proliferation. However, probiotics transiently decreased expression of an antimicrobial peptide, which may reduce immune protection in the gut. The yolk sac can also express tight junction proteins. The expression of tight junction proteins was affected by elevated incubation temperature in broiler embryos, which might be related to low hatchability of eggs exposed to heat stress. Avian defense peptides and pathogen recognition receptors were expressed in the YS, which implied that the yolk sac contained an innate immune function. The expression pattern of avian defense peptides was affected by breed (broilers and layers), while the expression level of avian defense peptides was greater in layers than broilers. In summary, the small intestine and the yolk sac are multifunctional organs. Their cell composition, structural integrity, and secretion of antimicrobial peptides can be affected by environmental factors, such as probiotic supplementation or high incubation temperature.
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Effects of high incubation temperature on the developing small intestine and yolk sac of broiler chicks with insight into goblet cell development in the small intestine early posthatchReynolds, Krista Lynn 07 August 2019 (has links)
The incubation period is crucial for development and overall quality of a chick. The selection for fast growing broilers has allowed the birds to reach market weight at a faster rate making the incubation period a larger portion of a broiler's life. A faster growth rate can lead to the release of more metabolic heat inside of the egg toward the second half of incubation because the embryo shifts to a homeothermic state. More heat being released into the incubator can cause the incubation temperature to rise if the incubator is not electronically regulated or cannot be ventilated properly due to malfunction. A high incubation temperature can impact the hatchability, growth, and development of the chick. This thesis provides a more in-depth analysis of the effects of high incubation temperature (37.5°C versus 39.5°C) on the developing small intestine and yolk sac, which provide the chick with nutrients posthatch and during embryogenesis. Studying these organs and mechanisms occurring during this time could potentially indicate why chicks from eggs subjected to a higher incubation temperature are not developing and growing properly. Chicks from eggs incubated at a higher temperature had lower body weights, lower hatchability and lower villus height in the duodenum, jejunum, and ileum. There were also differences seen in the depth of the crypt, which is the site for stem cells. Chicks from eggs incubated at a higher temperature had a lower crypt depth in the duodenum and jejunum. There was no difference in the expression of the intestinal stem cell marker olfactomedin 4 (Olfm4) and mucin 2, which is secreted by goblet cells and forms mucus. In the yolk sac, heat shock proteins (HSP) 70 and 90 were elevated at embryonic day 15, and HSP90 still remained elevated at embryonic day 17. Chicks from eggs incubated at a higher temperature showed greater expression of peptide transporter 1 and avian beta-defensin 10 mRNA at embryonic day 13. Even though small intestinal morphology was impacted early posthatch and expression of genes in the yolk sac were elevated at embryonic day 13, there does not seem to be a long-lasting effect on the development of the small intestine or the yolk sac. It is still important to study the impact of the incubation environment to understand the development and growth of the chicks and how different incubation factors can impact the overall hatchability and health of the chick. / Master of Science / The incubation period is crucial for development and overall quality of a chick. The selection for fast growing broilers has allowed the birds to reach market weight at a faster rate making the incubation period a larger portion of a broiler’s life. A faster growth rate can lead to the release of more metabolic heat inside of the egg toward the second half of incubation because the embryo shifts to a homeothermic state. More heat being released into the incubator can cause the incubation temperature to rise if the incubator is not electronically regulated or cannot be ventilated properly due to malfunction. A high incubation temperature can impact the hatchability, growth, and development of the chick. This thesis provides a more in-depth analysis of the effects of high incubation temperature (37.5°C versus 39.5°C) on the developing small intestine and yolk sac, which provide the chick with nutrients posthatch and during embryogenesis. Studying these organs and mechanisms occurring during this time could potentially indicate why chicks from eggs subjected to a higher incubation temperature are not developing and growing properly. Chicks from eggs incubated at a higher temperature had lower body weights, lower hatchability and lower villus height in the duodenum, jejunum, and ileum. There were also differences seen in the depth of the crypt, which is the site for stem cells. Chicks from eggs incubated at a higher temperature had a lower crypt depth in the duodenum and jejunum. There was no difference in the expression of the intestinal stem cell marker olfactomedin 4 (Olfm4) and mucin 2, which is secreted by goblet cells and forms mucus. In the yolk sac, heat shock proteins (HSP) 70 and 90 were elevated at embryonic day 15, and HSP90 still remained elevated at embryonic day 17. Chicks from eggs incubated at a higher temperature showed greater expression of peptide transporter 1 and avian beta-defensin 10 mRNA at embryonic day 13. Even though small intestinal morphology was impacted early posthatch and expression of genes in the yolk sac were elevated at embryonic day 13, there does not seem to be a long-lasting effect on the development of the small intestine or the yolk sac. It is still important to study the impact of the incubation environment to understand the development and growth of the chicks and how different incubation factors can impact the overall hatchability and health of the chick.
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Phenotypes and Survival of Hatchling LizardsWarner, Daniel Augustus 29 January 2001 (has links)
The phenotypes of hatchling reptiles are influenced by the environmental conditions that embryos experience during incubation, by yolk invested into the egg, and by the genetic contributions of the parents. Phenotypic traits are influenced by these factors in ways that potentially affect the fitness of hatchlings. The physical conditions that embryos experience within the nest affects development, hatching success, and hatchling phenotypes. Thus, the nest site that a female selects can influence the survival of her offspring as well as her overall fitness. In Chapter 1, I addressed this issue through a nest site selection experiment designed to determine the substrate temperature and moisture conditions that female eastern fence lizards (Sceloporus undulatus) select when provided a range of conditions from which to choose. In general, I found that females selected nest sites with conditions that yield high hatching success.
In Chapter two, I investigated the relative contributions of incubation moisture conditions, maternal yolk investment, and clutch (genotype) to variation in hatchling phenotypes and survival under field conditions. Eggs from 28 clutches were distributed among two moisture treatments; wet (-150 kPa) and dry (-530 kPa). In another treatment, yolk was removed from eggs to determine the affect of yolk quantity on hatchling phenotypes. After hatching, several phenotypic traits (mass, snout-vent length, tail length, body shape, thermal preference, running speed, desiccation rate, and growth rate) were measured. Hatchlings were subsequently marked and released at a field site in southwest Virginia. Hatchlings were recaptured twice weekly prior to winter and the following spring to monitor growth and survival. I found that incubation moisture and yolk removal affected only hatchling body size; individuals from the dry and yolk removed treatments were smaller in body size than those from the wet treatment. However, clutch was the most important source of phenotypic variation; all phenotypes were affected by clutch. Significant clutch effects suggested the possibility that phenotypic variation had at least some genetic basis. In the field, survival was not affected by incubation moisture and yolk removal, and overall survival was not associated with hatchling body size. Survivors and nonsurvivors differed only in growth rate in the field and running speed measured in the laboratory. Survivors ran faster and grew more slowly than nonsurvivors. To examine the association of clutch with survival, I used clutch mean values to look at the relationship between phenotype and survival. Clutches that produced relatively slow growing individuals and fast runners had higher survival rates than clutches that produced relatively rapid growing individuals and slow runners. In order to grow rapidly, an individual must eat more than slowly growing individuals. Thus, rapid growth rate may increase risk of predation through its association with foraging activity. Individuals that run fast should be capable of capturing prey and evading predators more effectively than individuals that run slowly. Overall, these results emphasize the importance of clutch to variation in phenotypes and survival in hatchling Sceloporus undulatus. / Master of Science
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A Continental-Scale Investigation of Factors Controlling the Vulnerability of Soil Organic Matter in Mineral Horizons to DecompositionWeiglein, Tyler Lorenz 30 July 2019 (has links)
Soil organic matter (SOM) is the largest terrestrial pool of organic carbon (C), and potential carbon-climate feedbacks involving SOM decomposition could exacerbate anthropogenic climate change. Despite the importance of SOM in the global C cycle, our understanding of the controls on SOM stabilization and decomposition is still developing, and as such, SOM dynamics are a source of major uncertainty in current Earth system models (ESMs), which reduces the effectiveness of these models in predicting the efficacy of climate change mitigation strategies. To improve our understanding of controls on SOM decomposition at scales relevant to such modeling efforts, A and upper B horizon soil samples from 22 National Ecological Observatory Network (NEON) sites spanning the conterminous U.S. were incubated for 52 weeks under conditions representing site-specific mean summer temperature and horizon-specific field capacity (-33 kPa) water potential. Cumulative CO2 respired was periodically measured and normalized by soil organic C content to obtain cumulative specific respiration (CSR). A two-pool decomposition model was fitted to the CSR data to calculate decomposition rates of fast- (kfast) and slow-cycling pools (kslow). Post-LASSO best subsets multiple linear regression was used to construct horizon-specific models of significant predictors for CSR, kfast, and kslow. Significant predictors for all three response variables consisted mostly of proximal factors related to clay-sized fraction mineralogy and SOM composition. Non-crystalline minerals and lower SOM lability negatively affected CSR for both A and B horizons. Significant predictors for decomposition rates varied by horizon and pool. B horizon decomposition rates were positively influenced by nitrogen (N) availability, while an index of pyrogenic C had a negative effect on kfast in both horizons. These results reinforce the recognized need to explicitly represent SOM stabilization via interactions with non-crystalline minerals in ESMs, and they also suggest that increased N inputs could enhance SOM decomposition in the subsoil, highlighting another mechanism beyond shifts in temperature and precipitation regimes that could alter SOM decomposition rates. / Master of Science / Soils contain a large amount of carbon (C) in the form of soil organic matter (SOM), and there is the potential for the increased decomposition of SOM due to warmer temperatures to cause climate change to become worse through the release of additional CO₂ into the atmosphere. However, we still do not know exactly what is most important for predicting how vulnerable SOM is to decomposition at continental scales, and this results in a substantial amount of uncertainty in Earth system models used to predict climate change. To address this question, the proportion of organic C decomposed in soil samples from the topsoil and subsoil from 22 sites across the conterminous U.S. was monitored over the course of a year under optimal moisture conditions and at site-specific summer temperature. Additionally, a mathematical model was fitted to the proportion of organic C decomposed over time to estimate decomposition rates of a quickly decomposing pool of SOM and a slowly decomposing pool of SOM. The proportion of organic C decomposed and decomposition rates were related to soil and site properties using multiple linear regression to find which soil and site properties were most important for predicting these response variables. The type of clay-sized mineral and SOM chemical composition were found to be important predictors of the proportion of organic C decomposed for both topsoil and subsoil samples. The important predictors for decomposition rates varied by pool and by topsoil vs. subsoil. For subsoil decomposition rates, it was found that a greater availability of nitrogen (N) increased decomposition rates, and in the quickly decomposing pool, it was found that fire-derived organic matter slowed decomposition rates. The results of this study showed the general importance of local factors for controlling SOM decomposition. Specifically, it showed that the type of clay-sized mineral present at a site needs to be considered as well as the fact that N might increase SOM decomposition in the subsoil.
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Effect of incubation temperature on Atlantic salmon metabolism as indicated by ventilation rate / Effekt av inkuberingstemperatur på laxens metabolism indikerad av gälslagsfrekvensVernerback, Claes January 2016 (has links)
The global mean temperature is predicted to increase by up to 5 °C during this century. For fish, being ectotherms, temperature is one of the most important environmental factors, influencing them in a number of different ways, including effects on physiological traits, timing of life history events and behavior. Atlantic salmon has been shown to grow faster after being incubated at warmer temperatures. One possible explanation for this could be that the increased incubation temperature causes decreased metabolic rates. The aim of this project was to examine whether this is true. Atlantic salmon eggs were incubated in three different temperature regimes: natural temperature conditions, heated water and a mixed temperature treatment, where eggs were incubated in increased temperature until the beginning of January and after that subjected to natural temperature conditions. Ventilation rate, a proxy for metabolism, was measured for fish from each treatment group, as well as fish length and weight. The results revealed significantly lower ventilation rates of the fish from the heated temperature treatment, but not of the fish from the mixed temperature treatment. This suggests that an increased incubation temperature causes lowered rates of metabolism in Atlantic salmon, and that the change occurs later than early January. Because of differences in size and life stage between fish from the different groups however, the results are uncertain and call for further investigations. A lowered metabolic rate will affect the fish’s behavior. A further development might therefore be to study fish survival in the wild in relation to a fish’s metabolic rate. / Jordens medeltemperatur beräknas öka med upp till 5 °C det här århundradet. För fiskar, som är ektotermer, är temperatur en av de viktigaste abiotiska faktorerna och påverkar dem på en mängd olika sätt, bland annat genom förändring av fysiologiska attribut, tidpunkter för steg i livscykeln och beteende. Lax har visats växa snabbare efter att ha blivit inkuberade i varmare vattentemperatur. En möjlig förklaring till det kan vara att en förhöjd inkuberingstemperatur orsakar en lägre metabolism. Det här projektet syftade till att undersöka om så är fallet. Ägg från lax inkuberades i tre olika temperaturförhållanden: naturliga temperaturförhållanden, förhöjd temperatur och en blandad temperaturbehandling, där ägg inkuberades i förhöjd temperatur till början av januari, varefter de utsattes för naturliga temperaturförhållanden. Gälslagsfrekvens, som fungerar som en indikator för metabolism, mättes på fisk från varje behandlingsgrupp, samt fiskarnas längd och vikt. Resultaten visade signifikant lägre gälslagsfrekvenser hos fiskarna från behandlingen med förhöjd temperatur, men inte hos fiskarna från behandlingen med blandad temperatur. Detta indikerar att en förhöjd inkuberingstemperatur orsakar en lägre metabolism hos lax, och att förändringen sker senare än tidiga januari. På grund av skillnader i storlek och livsstadier hos fiskarna från de olika grupperna är resultaten dock osäkra, vilket gör att ytterligare studier behövs. En lägre ämnesomsättning påverkar fiskars beteende. En uppföljning kan därför vara att studera fiskars överlevnad i det vilda i relation till deras metabolism.
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Statut endocrinien et effort de reproduction chez un oiseau marin longévif, le manchot Adélie, dans un environnement changeant / Endocrine status and reproductive effort of a long-lived seabird, the Adélie penguin, in a changing environmentThierry, Anne-Mathilde 13 September 2013 (has links)
L’étude des mécanismes endocriniens est particulièrement intéressante du fait du rôle majeur des hormones dans la régulation des interactions entre la physiologie d’un organisme, son comportement, et les modifications de son environnement. Cette thèse s’est intéressée aux relations entre le statut hormonal, les performances de reproduction et le succès reproducteur d’un oiseau marin longévif, le manchot Adélie Pygoscelis adeliae, dans un contexte environnemental soumis à des changements. Le statut endocrinien de manchots mâles a été manipulé en utilisant des implants dégradables sous-cutanés diffusant l’hormone d’intérêt ou un inhibiteur de sa sécrétion. Les effets d’une modification des niveaux d’hormones sur l’investissement parental pendant l’incubation ont été mesurés à l’aide d’observations directes et d’oeufsfactices enregistrant les paramètres d’incubation. Les niveaux de corticostérone – hormone dite de stress, de prolactine – hormone des soins parentaux, et de testostérone – hormone liée aux comportements sexuels et à l’agressivité, ont été manipulés. Les effets d’une augmentation des niveaux de corticostérone sur les performances et le succès reproducteur pendant la période de l’élevage des poussins ont également été mesurés. Enfin, les conséquences d’une légère élévation des niveaux de corticostérone pendant l’ensemble de la saison de reproduction en termes de comportement et de succès reproducteur ont été examinées. Une augmentation des niveaux de corticostérone a globalement diminué les performances et le succès de reproduction. D’autre part, une modification des niveaux de prolactine ou de testostérone a affecté la durée etles paramètres d’incubation, suggérant une implication de ces deux hormones dans le contrôle de la phénologie de la reproduction. Les résultats présentés dans cette thèse mettent l’accent sur le fait que la relation entre statut endocrinien et performances de reproduction est dose, état et contexte dépendante. Nos résultats illustrent le rôle majeur des hormones étudiées dans la régulation de l’effort reproducteur, et soulignent également l’importance de considérer les interactions entre les organismes et leur environnement. / Studying endocrine mechanisms is of particular interest because of the major role played by hormones in mediating interactions between an animal’s physiology, its behaviour, and both predictable and unpredictable regimes of environmental variation. During this PhD, I have investigated the relationships between endocrine status, reproductive performance, and reproductive output in a long-lived polar seabird, the Adélie penguin Pygoscelis adeliae, while integrating environmental parameters for some of the studies. The endocrine status of male penguins was experimentally modified using subcutaneous self-degradable pellets, which released either the hormone or an inhibitor of its secretion. The effects of changes in the levels of several hormones on the parental investment during incubation were assessed, using direct observations and dummy eggs to record incubation parameters. The levels of corticosterone – the so-called stress hormone, prolactin – the parental care hormone, and testosterone – the sexual behaviour and aggressiveness hormone, were manipulated. The effects of increased corticosterone levels on reproductive performance and output were also evaluated during the chick-rearing period. Finally, the behavioural consequences of a moderate elevation of corticosterone levels during the whole breeding cycle were assessed. On the whole, an increase in corticosterone levels decreased reproductive performances and output. Changes in prolactin or testosterone levels affected incubation duration and egg temperature, suggesting a role for these hormones in the control of the timing of breeding. The results prevented in this PhD highlight the fact that the relationship between endocrine status and reproductive performance is dose-, state-, and context-dependant. Our results illustrate the major role of the hormones considered in our studies in the regulation of reproductive effort. They also underline the importance of considering the interactions of organisms with their environment in studies of animal behaviour and ecophysiology.
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Effekter av inkuberingstemperatur på kroppsform och fenstorlek hos juvenil atlantlax (Salmo salar L.) / Effects of incubation temperature on body shape and fin size in juvenile Atlantic salmon (Salmo salar L.)Flytström, Annika January 2017 (has links)
Global warming, a consequence of the ongoing climate change, is expected to increase the mean global temperature by up to 5°C this century. This is predicted to have various impacts on the earth's ecosystems and especially on ectotherms which cannot regulate body temperature by endogenous heat production. There is an intensified interest in investigating the outcomes of climate change and the role of developmental phenotypic plasticity in relation to environmental conditions experienced early in life. Here I compare the body shape and fin size of juvenile Atlantic salmon that had been incubated at two different temperature regimes during embryogenesis. Morphometric methods were used to compare body size through a box-truss network of Euclidean distances and the data were then analyzed using discriminant analysis. Fin size was analyzed by comparing fin area using analysis of covariance with body size as the covariate. The fish incubated in ambient (cold) temperatures differed from the fish incubated in ca. 4°C warmer temperatures by having a deeper body shape and bigger pectoral fin area. There was no significant difference for dorsal fin area. My findings support the notion that Atlantic salmon are morphologically plastic when exposed to different temperature regimes during embryogenesis, but additional studies are needed to determine the ecological consequences of these changes. / Global uppvärmning, en konsekvens av pågående klimatförändringar, förväntas öka den globala medeltemperaturen med upp till 5°C det här århundradet. Det här förväntas ha stor påverkan på jordens ekosystem och speciellt ektotermer som inte kan reglera sin kroppstemperatur genom endogen värmeproduktion. Intresset har intensifierats för att undersöka klimatförändringarnas utfall och rollen som fenotypisk plasticitet har som svar på tidiga miljöförhållanden. Kroppsform och fenstorlek jämfördes hos juvenil atlantlax som inkuberats i två olika temperaturbehandlingar under embryogenesen. Morfometri användes för att undersöka kroppsformen genom ett box-truss nätverk av euklidiska avstånd som sedan analyserades med en diskriminant funktionsanalys. Fenstorleken analyserades genom att mäta fenornas area som sedan användes i en kovariansanalys med kroppsstorlek som kovariat. Fiskarna som inkuberades i normal (kall) temperatur skiljde sig från fiskarna som inkuberats i ca 4°C varmare temperatur genom att ha en djupare kroppsform och större area på bröstfenorna. Det fanns ingen signifikant skillnad mellan ryggfenornas area. Mina resultat stödjer idén att atlantlaxen är morfologiskt plastisk när den utsätts för olika temperaturbehandlingar under embryogenesen, men ytterligare studier behövs för att identifiera de ekologiska konsekvenserna av dessa förändringar.
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