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Data publikacji: 4 czerwca 2021
Data aktualizacji: 13 lutego 2022

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1

Wyile, Olive Geraldine. "Assessment of grey seal pup production from counts of pups". Thesis, University of Cambridge, 1988. https://www.repository.cam.ac.uk/handle/1810/265346.

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2

Carter, Matt. "From pup to predator : ontogeny of foraging behaviour in grey seal (Halichoerus grypus) pups". Thesis, University of Plymouth, 2018. http://hdl.handle.net/10026.1/13068.

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For young animals, surviving the first year of nutritional independence requires rapid development of effective foraging behaviour before the onset of terminal starvation. Grey seal (Halichoerus grypus) pups are abandoned on the natal colony after a brief (15-21 days) suckling period and must learn to dive and forage without parental instruction. Regional and sex-specific differences in diet and foraging behaviour have been described for adults and juveniles, but the early-life behaviour of pups during the critical first months at sea remains poorly understood. This thesis investigates sources of intrinsic and extrinsic variation in the development of foraging behaviour and resource selection in grey seal pups. The studies presented here feature tracking and dive data collected from 52 recently-weaned pups, tagged at six different breeding colonies in two geographically-distinct regions of the United Kingdom (UK). Original aspects of this thesis include: (Chapter I) a comprehensive review of analytical methods for inferring foraging behaviour from tracking and dive data in pinnipeds; (Chapter II) description and comparison of regional and sex differences in movements and diving characteristics of recently-weaned pups during their first trips at sea; (Chapter III) implementation of a novel generalized hidden Markov modelling (HMM) technique to investigate the development of foraging movement patterns whilst accounting for sources of intrinsic (age, sex) and extrinsic (regional) variation; and (Chapter IV) the first analysis of grey seal pup foraging habitat preference, incorporating behavioural inferences from HMMs and investigating changes in preference through time.
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3

章彤輝 i Tung-fai Cheung. "Maternal malnutrition: effects on growth and development of rat pups". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31236698.

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4

Cheung, Tung-fai. "Maternal malnutrition : effects on growth and development of rat pups /". Hong Kong : University of Hong Kong, 1997. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1971256X.

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5

Tan, H. M. "The emergence of the head direction system in pre-weanling rat pups". Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1469477/.

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This thesis characterises the head direction system in pre-weanling rats around the time of eye-opening. Head direction (HD) cells are neurons in a distributed network of brain areas that fire action potentials as a function of the animal’s directional orientation relative to its environment. Environmental sensory information and self-motion cues are used to update the directional signal, with visual landmarks being particularly salient in controlling the preferred firing directions of HD cells. HD cells have previously been shown to be adult-like as early as postnatal day 16 (P16) in the rat pup (Wills et al 2010, Langston et al 2010), just after its eyelids come unfused and coinciding with the first spontaneous exploration of its environment. To determine if the HD cell circuit can organise before the onset of patterned vision, I recorded from the postsubiculum (PoS) before eye-opening in pre-weanling rats. The earliest instance of HD cells is found at P12, three days before eye opening. This early HD signal carries low directional information content and lacks stability both within and across trials. However, once the eyes of the rats are open, the HD system matures rapidly, with a dramatic increase in the number of directional cells and the quality and reliability of their directional signal. A prominent visual landmark is also able to exert control over HD responses within 24 hr of eye-opening. The data suggest that the directional circuit can be organised in the absence of visual spatial information, while patterned vision is rapidly integrated once it becomes available, for accurate and reliable orientation in space.
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6

Skinner, John P. "Physical and behavioral development of nursing harbor seal (Phoca vitulina) pups in Maine". Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/SkinnerJP2006.pdf.

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7

Trottier, Geneviève. "Macronutrient composition of maternal diet affects hypothalamic-pituitary-adrenal responsiveness in developing rat pups". Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=20881.

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We studied the consequences of providing rat dams with elevated levels of dietary fat during lactation on stress responses in the offspring at different stages of development. High-fat feeding increased total milk lipid levels, and led to increased lipid deposition and plasma leptin levels in pups. Ten-day-old neonates from high-fat fed mothers had reduced stress responsiveness compared to controls. In contrast, 35-day-old pups from mothers fed high-fat diets showed greater stress-induced ACTH secretion. These findings indicate that maternal diet has effects on hypothalamic-pituitary-adrenal (HPA) responsiveness, which can persist after weaning to a normal rat chow diet. We also investigated macronutrient selection in the offspring, since differences in nutrient preferences may produce long-lasting consequences of lactational diet. However, our results did not support an involvement of maternal diet in postweaning nutrient selection. Furthermore, HPA stress responses were no longer related to maternal diet once offspring reached maturity.
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8

Trottier, Geneviève. "Macronutrient composition of maternal diet affects hypothalamic-pituitary-adrenal responsiveness in developing rat pups". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape10/PQDD_0002/MQ44302.pdf.

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9

Verrier, Delphine. "Extreme fasting in subantartic fue seal (Arctocephalus tropicalis) pups : Physiological adaptations and ecological implications". Université Louis Pasteur (Strasbourg) (1971-2008), 2007. http://www.theses.fr/2007STR13197.

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Ce travail examine les adaptations énergétiques, métaboliques, hormonales et comportementales mises en oeuvre lors des jeûnes répétés et prolongés auxquels le petit de l'Otarie d'Amsterdam doit faire face au cours de ses dix mois de croissance. Une attention particulière est portée à l'ontogénèse de ces adaptations. Le rôle clef de l'épargne énergétique et du stockage de réserves lipidiques est mis en évidence, de même qu'une très forte épargne des protéines corporelles qui ne contribuent qu'à 2% de la dépense d'énergie lors du jeûne. Parmi les différentes hormones considérées (hormones thyroïdiennes, cortisol, glucagon, insuline et leptine), le rôle de la leptine comme médiateur de l'adaptation au jeûne est pour la première fois mis en évidence chez un animal sauvage (autre que primates et rongeurs). Les capacités de résistance au jeûne augmentent avec l'âge, grâce à une réduction de la dépense énergétique et de l'activité comportementale, et aussi suite à une optimisation du niveau d'épargne protéique associée à une augmentation de l'adiposité. L'ensemble des résultats permet de comprendre comment les stratégies alimentaires maternelles pourraient être contraintes par ces changements ontogéniques de la tolérance au jeûne du petit. En outre, les compromis dévelopementaux imposés par les conflits énergétiques entre la croissance et les jeûnes répétés ont été étudiés à travers l’ontogénèse des capacités de plongée, afin d’estimer le coût, en terme d’histoire de vie, de restrictions alimentaires sévères au cours du dévelopement ainsi que leurs implications écologiques
The objectives of my thesis were to investigate the physiological and behavioural adaptations displayed by subantarctic fur seal pups in response to the repeated extended fasts they naturally undergo throughout their period of maternal dependence. Fasting energetics, associated endocrine changes and behavioural activity were examined in order to understand the adaptive mechanisms underlying the ontogeny of extreme fasting abilities in these animals. The adoption of an efficient strategy of energy conservation, fat storage and protein sparing (with body proteins contributing to less than 2% of total energy expenditure) in response to fasting is highlighted. Among the diverse hormones measured (thyroid hormones, cortisol, insulin, glucagon and leptin), the importance of leptin in the regulation of energetic and immune homeostasis in response to changes in nutritional state and body reserves is suggested for the first time in a free-ranging mammal (apart from primates and rodents). In addition, my results show that pup resistance to fasting develops progressively with age depending upon pronounced changes in metabolic rates and body fat stores. As a consequence, maternal foraging strategy could be constrained by ontogenetic changes in pup fasting abilities in this species. Furthermore, the trade-offs imposed by the conflicting demands of growing and surviving food deprivation upon the development of diving abilities and foraging skills were also explored in order to estimate the life history cost of extreme fasting in early life and its ecological implications
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10

Kagawa, Noriko. "Efficient production of matured oocytes and live pups from growing oocytes of adult female". Kyoto University, 2005. http://hdl.handle.net/2433/145027.

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Kyoto University (京都大学)
0048
新制・課程博士
博士(農学)
甲第11626号
農博第1482号
新制||農||906(附属図書館)
学位論文||H17||N4019(農学部図書室)
23269
UT51-2005-D375
京都大学大学院農学研究科応用生物科学専攻
(主査)教授 久米 新一, 教授 今井 裕, 教授 廣岡 博之
学位規則第4条第1項該当
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11

Teng, Carolyn J. "Effects of intraplantar injection of inflammatory mediators in 3 and 15 day old rat pups". Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27422.

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The formalin model of inflammatory pain assesses the behavioural response to an injection of dilute formalin into the paw of a rodent. In adult rats, the behavioural response is related to the log of the formalin concentration. Very brief pain responses can be produced by injection of inflammatory mediators, and combination of 5-HT with other mediators produces a synergistic increase in the response.
The present study has two aims: (1) to determine the behavioural indices that best measure formalin-induced pain in 3 and 15 day old rat pups, and (2) to examine the behavioural response of infant rats to intraplantar injection of single inflammatory mediators and paired combinations of mediators. In Experiment 1, ascending concentrations of formalin were injected subcutaneously into the plantar surface of one rear paw.
In Experiment 2, ascending doses of 5-HT, PGE$ sb2$, bradykinin, or substance P were injected and the measures that were quantitatively related to formalin concentration used to assess pain. The data suggest that strong responses to formalin in young neonatal rats are not only a consequence of the continuing development of brainstem-spinal inhibitory systems, but may also be due to immaturity of peripheral pain transduction mechanisms. (Abstract shortened by UMI.)
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12

Teng, Carolyn J. "Effects of intraplantar injection of inflammatory mediators in 3 and 15 day old rat pups". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ29797.pdf.

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13

Moore, Jeremy Alan. "Effects of Subcutaneous Postnatal Choline Supplementation on Hippocampus-Mediated Learning and Memory in Rat Pups". Wright State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=wright1213369647.

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14

Weitzner, Emma. "The Development of Diving Capabilities in Weddell seal (Leptonychotes weddellii) Pups Throughout Early Ontogeny". DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2046.

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Weddell seals (Leptonychotes weddellii) are among the deepest diving pinnipeds (i.e., seals, sea lions, and walrus) and one of the best studied marine mammals in the world; as such, these seals are considered a model species for the study of diving physiology and behavior. Adult Weddell seal dive physiology is rather comprehensively understood, yet previous research has excluded an examination of pups’ initial independent diving attempts, beginning instead with the diving capabilities of near-weaning individuals at four to five weeks of age. This is beyond the point many pups have attempted their first independent dives; pups begin to enter the water at 8-10 days after birth, with some observed in the water earlier. The aim of this study was to investigate the development of diving capabilities and fine-scale behaviors of Weddell seal pups beginning at one week of age throughout their dependence period. Pups were sampled longitudinally at 1, 3, 5, and 7 weeks of age. Total body oxygen stores (TBO2, mL O2) were calculated as the sum of blood, muscle, and lung oxygen stores for each seal at all time points. Blood samples were collected under sedation, muscle oxygen parameters were interpolated, and lung oxygen content was extrapolated from adult values. Flipper-mounted time-depth recorders were used to collect concurrent dive behavior data. In chapter 1, I hypothesized that diving capability (TBO2) would be more strongly correlated with dive experience than calendar age; to examine this, age, mass, and diving parameters were correlated with oxygen stores. I instead found mass and age were most significantly correlated with individual tissue oxygen stores and TBO2. I predicted diving experience would be an important driver of oxygen storage development due to hypoxia exposure, but pups spent the majority of their time in the water at the surface and had little to no exposure to hypoxia during dependence. Increases in mass may enable early advances in diving ability, and with increased diving capabilities, pups will be able to become successful independent foragers. Later exposure to hypoxia may be the key to the subsequent increases in TBO2 observed in yearlings and juveniles. In chapter 2, I used TDR data to predict when pups would be in the water based on developmental, temporal, and environmental factors including age, weaning status, time of day, and weather parameters. Pups spent the most time in the water and made their deepest, longest, and most frequent dives during the late night and early morning hours. These data indicate pups are following the diving patterns of their mothers, which follow the diurnal vertical migration of their prey. The data also suggest Weddell seal pups most likely prioritize learning to swim and navigate as opposed to practicing foraging while still dependent. It is critical for pups to develop their swimming, navigational, and diving abilities while they are still with their moms to ensure their survival. This study is the first to describe the complete trajectory of the development of diving physiology and behavior in Weddell seal pups throughout dependence. It is important to understand how the internal diving physiology of Weddell seal pups develops because this directly determines their diving capabilities and their ability to forage successfully, which in turn directly correlates with their survival. Pup survival is an indicator of population growth rates, so the development of diving physiology in pups can lend insights into larger population-level trends.
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15

Alexander, Vincent Rasahd. "The Role of Corticotropin-Releasing Factor in the Behavior and Proinflammatory Activity of Separated Guinea Pig Pups". Wright State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=wright1345847290.

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16

MacRae, Amelia. "Hand-rearing harbour seal pups (Phoca vitulina) : the effect of diet and supplementary heat on growth and survival". Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/17407.

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Hundreds of stranded harbour seals pups (Phoca vitulina) are brought to wildlife rescue centres every year, often unweaned and in poor body condition. Typical hand-rearing diets include artificial milk-replacers and diets based on macerated fish, both normally fed via gavage. Mortality rates for these animals can be high and weight gains on artificial formulas are low. This study was designed to determine the effect of the following treatments on the growth and survival of captive orphaned seals: (1) feeding pups an artificial milk-replacer versus a fish-based formula; and (2) the provision of supplementary heat. Pups admitted to the facility in summer 2007 (n=145) and 2008 (n=98) were randomly assigned to one of two diets and fed until weaning at roughly 20 days of age. In 2008, 25 pups were also provided with a supplementary heat source. Diet and heat treatments were compared using average daily gain (ADG) and mortality rates. In 2007, with pups fed formulas at 8% of body weight per day, pups fed milk-replacer gained more (43 g/d ± 12, mean ± SEM) than those fed fish-formula (loss of 13 g/d ± 6; p<0.01) and their survival to weaning was twice as high (p<0.05, chi-squared analysis). In 2008, with daily intake increased to 11% of body weight per day, weight gain was improved for both diets but remained higher on milk-replacer (123 g/d ± 12, loss of 6 g/day ± 8; p<0.01) and fewer seals died on either treatment (6/35 on milk replacer, 8/34 on fish formula.) Pups provided with heat did not show any differences in ADG (p>0.05) or survival rate (p>0.05) but did show increased heat-seeking behaviour at ambient temperatures below 16°C (p<0.001). I conclude: (1) although neither diet achieved the weight gains recorded in mother-raised pups (400 – 800 g/d), the artificial milk formula was clearly more successful; (2) supplementary heat can be safely used for unweaned pups in poor body condition at ambient temperatures <16°C; and (3) more work is needed on both diet composition and feeding method to achieve higher survival and more natural weight gains.
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17

Simms, Wendy Alison. "Natural and anthropogenic factors affecting the circulatory vitamin A dynamics of free-ranging harbour seal (Phoca vitulina) pups". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0017/MQ48205.pdf.

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Fraissard, camille. "Experimental release of hand-reared wolf pups in Tver region (Russia): food habits, movement patterns and fear of humans". Thesis, Linköpings universitet, Zoologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-68743.

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Studying the reintroduction of hand-raised wolves may embrace several interests such as deepening knowledge on wolf biology and allowing a controlled release in isolated populations in need of genetic influx. Studies on hand-raised wild animals, showing successful reintroduction, suggested that young released wolves might be able to survive in the wild without previous fastidious training. Most of their survival behaviours would be instinctive. In this study, nine young wolves were reintroduced in Tver region (Russia) and followed in order to evaluate their fear of humans, their movement patterns, thanks to GPS-Argos collars fitted to three of the animals, and assess their diet via four methods of scats analysis. We analyzed 46 wolf scats collected from August 2010 to January 2011. We determined the frequency of occurrences of items per scats and per items, and used the Relative Estimated Bulk to estimate the biomass of prey species consumed. Statistics were conducted to test for significance of method comparisons. The results showed that half of the wolves remained near the enclosure weeks to months after release, occasionally leaving the vicinity. The individual wolves behaved differently, they adopted various movement patterns and had diverse home ranges (from 15 km2 to 40 km2). Released wolves preyed more on ungulates, especially moose and on other wild mammals such as mountain hare. They also sporadically hunted domestic animals and regularly consumed vegetal matter along with smaller animals as alternative prey. Finally, all scat-analysis methods significantly assessed (p < 0.01) the relative importance of the main food types.
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19

Sørmo, Eugen Gravningen. "Organochlorine pollutants in grey seal (Halichoerus grypus) pups and their impact on plasma thyroid hormone and vitamin A concentrations". Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for biologi, 2005. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-693.

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Studies on laboratory animals suggest that developing and newborn mammals are more vulnerable than the adults with respect to the harmful effects of organochlorine (OC) pollutants such polychlorinated biphenyls (PCBs) and OC pesticides (Brouwer et al. 1995; 1998a; Colborn 2004). These effects include neurobiological and neurochemical effects, reproductive effects, reduced brain and circulatory thyroid hormone levels, impaired immune functions and vitamin A homeostasis (Brouwer et al. 1995; Colborn 2004; Safe et al. 1994; Tryphonas 1994). In humans, several of these negative effects of OCs have been reported in children of mothers with high pollutant burdens (Jacobson and Jacobson 1996, 1997; Koopman-Esseboom et al. 1994; Sandau et al. 2002; ten Tusscher et al 2003; Weisglas- Kuperus et al. 2000, 2004). Most organochlorines are highly lipophilic and resistant against degradation, and biomagnify as a function of the trophic level in food webs. Due to long food chains and the lipid richness of marine ecosystems, marine apex predators, such as seals, often accumulate very high burdens of these compounds (Aquilar et al. 2002), exemplifying the particular concern about toxic effects in these species. Studies of newborn phocid seals may be particularly interesting, because seals have lipid rich milk, resulting in the nursed grey seal pups being exposed to relatively high concentrations of OCs (Addison and Brodie 1977, 1987: Addison et al. 1999; Debier et al. 2003; Green et al. 1996; Pomeroy et al. 1996; Schweigert and Stobo 1994) during a period of their life when their endocrine and neural systems are still under development, and under the influence of the potentially disruptive properties of these pollutants (Hall et al. 1998; Simms et al. 2000b). Particularly high concentrations of OCs have been found in seals from the Baltic Sea as compared to seals from the North-Atlantic Ocean (Jenssen 1996; Nyman et al. 2002), and it has been suggested that these high exposure levels severely affects the health of Baltic seals (Bergman 1999; Bergman et al. 2001; Helle et al. 1976a,b; Nyman et al. 2001, 2003; Olsson et al. 1994). Given that the developing mammal might be particularly susceptible to the effects of OCs, it is of special interest to examine possible OC related effects that newborn seals may suffer from. Results from such a study may also predict the effects of OCs on marine mammals in general and possibly on humans (Jenssen 2003).
Paper I and paper IV are reprinted with kind permission of Elsevier, sciencedirect.com
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20

Yap, Carol Sue Lynn Psychology Faculty of Science UNSW. "An analysis of late-developing learning and memory systems in rats: fear-potentiated startle and context-specific latent inhibition and extinction". Awarded by:University of New South Wales. Psychology, 2006. http://handle.unsw.edu.au/1959.4/24374.

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Eleven experiments examined two late-developing learning and memory systems in rats: fear-potentiated startle (FPS) and the contextual regulation of latent inhibition and extinction. The first study was based on three previous developmental findings on FPS: (1) FPS to an odour CS emerges at postnatal day (PN) 23; Rats conditioned at PN16 to an odour CS express freezing but not FPS when tested at PN23, and (3) FPS to an odour CS trained at PN16 is activated if rats are also trained to a difference odour at PN23 (Yap, Stapinski, & Richardson, 2005). Yap et al. (2005) hypothesised that the activation effect only occurs if rats are given training to the second odour at an age when FPS has emerged. Study 1 assessed this hypothesis and trained the second odour CS at either PN23 or PN20. Contrary to expectations, the results of this study showed the activation effect for both groups of rats. Surprisingly, the results also revealed a significant FPS effect to the odour CS trained at PN20. Subsequent experiments examined this unexpected result, and found that learning to odour 1 at PN16 facilitated the age of onset for FPS at PN20. The results of Study 1 are discussed in relation to past findings on enrichment, cumulative learning, and neurobiological models of conditioned fear. The second section of this thesis (Studies 2 and 3) examined the context-specificity of two memory interference paradigms, latent inhibition and extinction, in developing rats. The studies found that both phenomena were context-specific at PN23-25 but not at PN16-18. Moreover, the results suggest that the context-specificity of both latent inhibition depended on the age of the rat during the second phase of training, but not their age during the first phase of training or their age at test. The implications of these findings for theoretical and neural models of learning, as well as the occurrence of latent inhibition and extinction during development are discussed.
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21

Roitt, S. M. "An investigation into the effects of lymphocyte derived soluble factors on mixed glial cell cultures from cerebra of 1-2 day old neonatal CFHB rat pups". Thesis, University of York, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235001.

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22

Pedroso, Taíse Fonseca. "Avaliação da toxicidade do chumbo em parâmetros bioquímicos e comportamentais: efeito preventivo do zinco e n-acetilcisteína". Universidade Federal de Santa Maria, 2017. http://repositorio.ufsm.br/handle/1/12772.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Lead (Pb) is a toxic metal without biological function, which can cause various undesirable changes in organism. Developing animals are more sensitive to external aggressions, and exposure to Pb may cause pronounced and even irreversible damage. Studies show detoxifyng action by zinc chloride (ZnCl2) and N-acetylcysteine (NAC), suggesting same protective effect against intoxication with Pb. Therefore, we investigated the toxic effect of lead acetate (AcPb) on biochemical and behavioral parameters, in developing animals, and the possible protective effect of ZnCl2 and NAC. For this young Wistar rats received subcutaneously: saline, ZnCl2 (27 mg/kg), NAC (5 mg/kg) or more NAC ZnCl2 from the 3rd to 7 th; and AcPb (7 mg/kg) or saline from the 8th to 12th day of age. The animals were subjected to behavioral tasks: negative geotactismo, the tail immersion test beaker and open field to assess neurological damage and motors. They were sacrificed at 33 days and the biological samples were stored for further analysis. We assessed the body weight, the activity of porphobilinogen synthase (PBG synthase) in blood, acetylcholinesterase (AChE) in brain and cerebellum, hemoglobin (Hb) in whole blood, serum urea and creatinine, and blood, cerebrum and cerebellum levels. Pups exposed to AcPb presented a decrease of blood PBG-synthase activity, without changes in Hb content. ZnCl2 pre-exposure partially prevented the PBG-synthase inhibition. Pb caused a decrease in the activity of brain AChE, while the treatment with ZnCl2, NAC and ZnCl2 more NAC prevented this change. In addition, animals exposed to AcPb presented Pb accumulation in blood and brain; all preventive treatments decreased Pb levels. In summary, the results show that there was an accumulation of Pb and inhibition of the activity of two enzymes, which are important biomarkers of toxicity. As preventive treatments, the protector effect of ZnCl2 may related to its capacity of to induce the biosyntese of metal ligant proteins. As to NAC, it is probable that its protective effect is related to chelating effects.
O chumbo (Pb) é um metal tóxico, sem função biológica, o qual pode provocar várias alterações indesejadas no organismo. Animais em desenvolvimento apresentam maior sensibilidade à agressões externas, e a exposição ao Pb poderá provocar danos pronunciados e até mesmo irreversíveis. Alguns trabalhos sugerem que o cloreto zinco (ZnCl2) e a N-acetilcisteína (NAC) possuem ação detoxificante, podendo então, ter um efeito protetor frente a uma intoxicação com Pb. Sendo assim, buscamos investigar o efeito tóxico do acetato de chumbo (AcPb) em parâmetros bioquímicos e comportamentais, quando administrado em animais em desenvolvimento, e a possível ação protetora do ZnCl2 e da NAC sobre esta toxicidade. Para isso ratos Wistar jovens receberam subcutaneamente: salina, ZnCl2 (27 mg/kg), NAC (5 mg/kg) ou ZnCl2 mais NAC do 3o ao 7o; e AcPb (7 mg/kg) ou salina do 8o ao 12o dia de idade. Os animais foram submetidos às tarefas comportamentais: geotactismo negativo, imersão da cauda, teste do becker e campo aberto para avaliação de danos neurológicos e motores. Foram sacrificados aos 33 dias e as amostras biológicas foram guardadas para análises posteriores. Avaliou-se: o peso corporal; a atividade das enzimas porfibilinogênio-sintase (PBG-sintase) em sangue, acetilcolinesterase (AChE) em cérebro e cerebelo; níveis de hemoglobina (Hb) em sangue total, de ureia e creatinina em soro; níveis de metalotioneíanas (MT) em sangue, fígado e cérebro; dosagem de metais em sangue, cérebro e cerebelo. Filhotes expostos ao AcPb apresentaram diminuição da atividade da PBG-sintase de sangue, sem alterações no conteúdo de Hb. O ZnCl2 preveniu parcialmente a inibição PBG-sintase. O AcPb causou diminuição na atividade da AChE de cérebro, enquanto os tratamentos com ZnCl2, NAC e ZnCl2 mais NAC preveniram essa alteração. Além disso, os animais expostos ao AcPb apresentaram acúmulo de Pb em sangue e cérebro; todos os tratamentos preventivos diminuiram os níveis de Pb. Em resumo, os resultados mostram que houve um acúmulo de Pb nos tecidos onde houve inibição das enzimas, que são importantes biomarcadores de toxicidade; acredita-se que a inibição ocorra através da ligação do metal aos grupamentos tiois das enzimas. Quanto aos tratamentos preventivos, o efeito protetor do zinco pode estar ligado a indução de proteínas ligantes de metais. Ainda, sugere-se que a proteção exercida pela NAC está ligada a sua capacidade quelante.
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23

Guilhermitti, Ana Carolina. "Comportamento de filhotes de rato (Rattus norvegicus) em um campo aberto na presença e na ausência de animais adultos". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/59/59134/tde-12072011-185115/.

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Vários estudos realizados com roedores permitem analisar, entre outros fatores, as respostas dos animais à novidade, a emocionalidade e locomoção dos animais. Para tal, vários testes tem sido empregados e um dos mais utilizados é o do campo aberto. O presente estudo visa analisar o papel da presença de um animal adulto da mesma espécie, ou de espécie diferente, no comportamento exploratório e na ocupação das áreas de um campo aberto por filhotes de rato, testados em duas condições: agrupados ou individualmente. Na primeira condição os testes de exploração foram feitos em um campo aberto. Em uma das paredes do campo aberto foi acoplada uma gaiola que em diferentes momentos continha uma fêmea da mesma espécie (Rattus norvegicus), um macho da mesma espécie (ambos não familiarizados com os filhotes), a própria ama-de-leite ou uma fêmea de outra espécie, no caso, uma cobaia (Cavia porcelus). As sessões experimentais foram realizadas no vigésimo quinto dia de vida dos filhotes. Os animais foram divididos em cinco ninhadas compostas por oito filhotes cada uma: quatro machos e quatro fêmeas., testados juntos em uma única sessão. O primeiro grupo foi testado no campo aberto sem qualquer tipo de estímulo na gaiola. Os outros grupos foram testados, respectivamente, na presença da ama-de-leite, de uma outra rata, de um rato macho ou de uma cobaia. Na segunda condição, os sujeitos de outras cinco ninhadas foram testados nas mesmas circunstâncias, porém individualmente. Os resultados mostraram que a presença de um animal adulto altera a preferência pela ocupação dos cantos mais estruturados por filhotes de rato em campo aberto. Quando o adulto presente é um co-especifico, a tendência dos filhotes é de se aproximar do local onde o animal se encontra (gaiola). Na presença de um animal de outra espécie, a tendência é, num primeiro momento, de aproximação e posteriormente de permanência nos locais mais estruturados do campo aberto, como as áreas de duas paredes, igual aos testados com a gaiola vazia. Os animais apresentaram diferenças de comportamento devidos ao agrupamento. Os filhotes agrupados frequentaram mais a periferia do campo aberto e passaram mais tempo nestas áreas que os testados individualmente, que por sua vez tendem a se aproximar mais do adulto do que os testados em grupo. Na idade em que foram testadas, as fêmeas mostraram-se menos ansiosas que os machos. De um modo geral, a principal conclusão é a de que filhotes de rato expostos a um campo aberto na presença de um adulto, exibem preferência pelas proximidades do adulto quando este é um co-específico, tendendo a permanecer nas áreas mais estruturadas quando o animal presente é de outra espécie.
Several studies with rodents allow us to analyze, among other factors, the responses of animals to novelty, emotionality and locomotion of animals. For this, several tests have been used and one of the most frequently used is the open-field. The present study aims at examining the role of the presence of an adult animal of the same species, or of a different species, in the exploratory behavior and the occupation of areas of an open-field by rat pups, tested in two conditions: grouped and individually. In the first condition, exploration tests were done in an open-field. In one wall of the open-field a cage was connected which, in different occasions, contained a female of the same species (Rattus norvegicus), a male of the same species (both unfamiliar to the pups), the dam or a female of another species, in this case, a guinea-pig (Cavia porcelus). The experimental sessions occurred at the twenty-fifth day of life of the of pups. The animals were divided into five eight-pup litters with four males and four females, which were tested together in a single session. The first group was tested in the open-field without any kind of stimulus in the cage. The other groups were tested, respectively, in the presence of the dam, another female, a male or a female guinea-pig. In the second condition, all subjects in a litter were tested under the same circumstances, but individually. The results showed that the presence of an adult animal changes the preference for the occupation of the more structured corners by rat pups in the open-field. When the animal in the cage was an adult co-specific, the tendency of the subjects was to approach the place where the adult animal was (the cage). In the presence of an animal of another species, the trend was, at first, to approach and subsequently to spent more time in the most structured corners of the open-field, areas with two walls. The animals showed behavioral differences due to grouping. The grouped pups went more often to the periphery of the open-field and spent more time in these areas than those tested individually, which, in turn, tended to be close to the adult longer than the grouped subjects. At the age they were tested, female infants were less anxious than males. In general, the main conclusion is that rat pups exposed to an open-field in the presence of an adult, exhibit a preference for the vicinity of the adult when it is a co-specific, tending to remain in the more structured areas when the cage was empty or when the animal in the cage belonged to another species.
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24

Prigol, Marina. "Ação convulsivante do disseleneto de difenila em ratos: estudo dos mecanismos neuroquímicos e da toxicocinética". Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/4418.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
In recent years have been identifical numerous pharmacological properties of a selenium compound, diphenyl diselenide [(PhSe)2]. Consequently, it is important the investigation of its toxic effect for a safe application in pharmacological studies. It is known that babies, in particular, have many physiological and biochemical changes related to development, which increase the susceptibility to toxic effects of drugs. Thus, the article 1 investigated the appearance of seizure episodes induced by (PhSe)2 when administered orally at doses of 5 to 500 mg/kg in rat pups (pos natal day 12-14) and the possible glutamatergic (article 2) and GABAergic (article 3) mechanisms involved in this process. Some studies using different experimental models have demonstrated the most different pharmacological and toxicodynamics properties of (PhSe)2. However, little is known about the toxicokinetic disposition of this compound. Therefore, the aim of article 4 was to determine and quantify the plasma levels of (PhSe)2 in adult mice and rats after oral (p.o.) administration of 500 mg/kg (PhSe)2; to verify the involvement of different routes of administration, vehicle and animal species in plasma levels of (PhSe)2 and in the onset of the first seizure episode induced by it. In article 5, it was determined and quantified the levels of (PhSe)2 in plasma, liver and brain of rat pups and these levels were correlated to the latency for the onset of the first seizure episode. To obtain more information about the compound, which were to supplement the data obtained, we carried out in vitro kinetic models. The manuscript 1 investigated the drug-like properties of (PhSe)2 in regards to stability, solubility, absorption and plasma protein binding (PPB) in vitro. In manuscript 2, it was conducted an in vitro study in order to identify possible metabolic pathways responsible for the biotransformation of (PhSe)2 in the body. Results of article 1 showed that administration of (PhSe)2 caused toxicity in rat pups, evidenced by the appearance of seizures. These were dose dependent and were, at least in part, related to oxidative stress. Among the mechanisms involved in the convulsive effect of (PhSe)2 were the interaction with: glutamatergic system by stimulating the inotropic glutamatergic receptors NMDA and by inhibiting the uptake of glutamate (Article 2); GABAergic system by antagonize the GABAA receptor, stimulating GABA transaminase enzyme and increasing GABA uptake (Article 3). The article 4 revealed that the maximum concentration of (PhSe)2 in the plasma of adult rats and mice occurred 30 minutes after p.o administration of the compound and remained detectable up to 8 hours after administration. The use of different routes of administration (intraperitoneal (i.p.), p.o., subcutaneous (s.c.)) or vehicle (canola oil or dimethyl sulfoxide (DMSO)) in rats and mice indicated that the onset of the first seizure episode and plasma levels are dependent on the route of administration (i.p. > p.o. > s.c.), vehicle (DMSO > canola oil) and animal species (mouse > rat). In article 5, it was observed that rat pups showed seizures even presenting lower plasma values of (PhSe)2 as compared to adults. This result demonstrated that rat pups are more sensitive to the toxic effects of (PhSe)2 than adult rats. Levels of (PhSe)2 in the liver and brain of rat pups showed a negative correlation with the latency to the first seizure episode. The manuscript 1 showed that (PhSe)2 has chemical and biological stability. However, the compound has a low solubility in water, a high partition coefficient octanol-water and an extensive plasma protein binding. Manuscript 2 indicated that (PhSe)2 is not biotranformed by Phase I reactions, catalyzed by cytochrome P450. It reacted chemically with reduced glutathione (GSH) and N-acetylcysteine (NAC) to form adducts or reacts with protein SH groups. The presence of GSH or NAC in the incubation medium decreased the binding of (PhSe)2 protein. Finally, it was observed that (PhSe)2 reduced the activity of cytochrome P450. Together, the data presented showed that the intensity of toxic effects caused by (PhSe)2 are directly related to its toxicokinetic.
Nos últimos anos, têm sido identificadas inúmeras propriedades farmacológicas do composto de selênio disseleneto de difenila [(PhSe)2]. Assim, a pesquisa dos efeitos tóxicos deste composto torna-se importante para a segurança na aplicação farmacológica. Sabe-se que os bebês, em particular, apresentam muitas mudanças fisiológicas e bioquímicas relacionadas ao desenvolvimento, que aumentam a suscetibilidade aos efeitos tóxicos de drogas. Desta forma, no artigo 1 investigou-se o aparecimento de convulsões induzida pelo (PhSe)2, quando administrado pela via oral (p.o), nas doses de 5 à 500 mg/kg em ratos bebês (12-14 dias de vida) bem como os possíveis mecanismos glutamatérgicos (Artigo 2) e GABAérgicos (Artigo 3) envolvidos em tal processo. Vários estudos, utilizando diferentes modelos experimentais demonstraram as mais diferentes propriedades farmacológicas e toxicodinâmicas do (PhSe)2 no entanto, pouco se conhece sobre a toxicodinâmica deste composto. Por isso, o objetivo do artigo 4 foi determinar e quantificar os níveis plasmáticos de (PhSe)2 em ratos e camundongos adultos após a administração p.o. de (PhSe)2 na dose de 500 mg/kg; bem como verificar o envolvimento de diferentes vias de administração, veículos e espécie animal nos níveis plasmáticos do composto e no aparecimento de convulsões induzidas pelo mesmo. No artigo 5, determinou-se e quantificou-se os níveis de (PhSe)2 no plasma, fígado e cérebro de ratos bebês e correlacionou-se estes níveis à latência para o aparecimento de convulsões. Devido a necessidade de obter mais informações sobre o composto, que viessem a complementar os dados obtidos, realizou-se modelos cinéticos in vitro. O manuscrito 1 investigou parâmetros relacionados a estabilidade, solubilidade, absorção e ligação às proteínas plasmáticas do (PhSe)2 in vitro. No manuscrito 2 realizou-se um estudo in vitro para identificar as vias metabólicas responsáveis pela biotransformação do (PhSe)2 no organismo. Os resultados do artigo 1 demonstraram que a administração de (PhSe)2 causou toxicidade em ratos bebês, evidenciada pelo aparecimento de convulsões. Estas são dependentes da dose utilizada e estão, pelo menos em parte, relacionadas ao estresse oxidativo. Dentre os mecanismos neuroquímicos envolvidos no efeito convulsivante do (PhSe)2 estão a interação com o sistema glutamatérgico, por estimular os receptores glutamatérgicos ionotrópicos do tipo NMDA e por inibir a captação de glutamato (Artigo 2); e com o sistema GABAérgico, por antagonizar os receptores GABAégicos do tipo GABAA, estimulando a enzima GABA transaminase e estimulando a captação de GABA (Artigo 3). O artigo 4 demonstrou que concentração máxima de (PhSe)2 no plasma de ratos e camundongos adultos ocorreu 30 minutos após a administração pela via oral do composto e permaneceu detectável até 8 horas após sua administração. O uso de diferentes vias de administração (intraperitonial (i.p); p.o; subcutânea (s.c)) e veículo (óleo de canola ou dimetil sulfóxido (DMSO)) em ratos e camundongos indicou que o aparecimento de convulsões e os níveis plasmáticos de (PhSe)2 são dependentes da via de administração (i.p > p.o > s.c), do veículo (DMSO > óleo de canola) e da espécie animal (camundongo > rato). No artigo 5 observou-se ainda que os ratos bebês convulsionaram mesmo apresentando níveis plasmáticos menores de composto que os adultos, o que nos leva a crer que estes são mais sensíveis aos feitos tóxicos do (PhSe)2. Os níveis de (PhSe)2 no fígado e no cérebro de ratos bebês no momento do episódio convulsivo apresentaram uma correlação negativa com a latência para o primeiro episódio convulsivo. O manuscrito 1 revelou que o (PhSe)2 apresenta estabilidade química e biológica. No entanto, o composto apresenta uma baixa solubilidade em água, um alto coeficiente de partição octanol-água e uma extensa ligação às proteínas plasmáticas. O manuscrito 2 indicou que o (PhSe)2 não é biotransformado por reações de fase I catalizadas pelo citocromo P450. O composto reage quimicamente com a glutationa reduzida (GSH) e a N-acetilciateína (NAC), formando adutos ou ainda reage com grupos SH de proteínas. A presença de GSH ou NAC no meio de incubação diminuiu a ligação do (PhSe)2 às proteínas. Por fim, foi observado que o (PhSe)2 reduziu a atividade das enzimas do citocromo P450. Em conjunto, os resultados desta tese demonstraram que a intensidade dos efeitos tóxicos causados pelo (PhSe)2 estão diretamente relacionados a sua toxicocinética.
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25

Mortimer, Geoffrey H. "The coil pumps". Thesis, Loughborough University, 1988. https://dspace.lboro.ac.uk/2134/16296.

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A family of Coil Pumps has been developed at Loughborough University over the last 10 years by the author. The coil pump, sometimes known as the 'hydrostatic pump', was known and used in the 18th and 19th centuries, since then it appears to have been forgotten. Laboratory investigations lead to a theory for predicting the behaviour of this little known pump The theory is based on an assessment of the boundary levels of the liquid plugs within the loops. From this work, two types of suction pump were derived and the lift pump theory was developed and adapted to predict their behaviour. One suction pump was based on one helical coil and it required a regulated air supply. The second pump used two helical coils 'back to back' one taking water into the pump and the other (of larger capacity) withdrawing it. Laboratory tests were carried out on a number of versions of both suction pumps and the experimental results agreed well with those produced by the theory. Practical applications of this family of pumps included a low cost stream powered lift pump, a dosing pump, a sewage suction pump and a sewage treatment process.
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26

Byrd, Tommy. "Ballistic atom pumps". W&M ScholarWorks, 2015. https://scholarworks.wm.edu/etd/1539623999.

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Researchers have long been interested in electron transport through mesojunctions containing time-dependent potential energies, a process often called "quantum pumping." A useful model of such a system is a ballistic atom pump, which consists of two reservoirs of neutral ultracold atoms connected by a channel containing oscillating repulsive potential-energy barriers. Under certain conditions, such pumps can create net transport of atoms from one reservoir to the other, and energy can be pumped out of or into each reservoir even when there is no net particle transport. These pumps are studied from classical and quantum-mechanical perspectives, and semiclassical theory is used to explain some scattering properties which are not easily explained by quantum theory. This system is also a nice model of chaotic transport. Escape-time plots showing the time for classical trajectories to escape the barrier region display a type of fractal self-similarity. A topological theory using a discrete map of the system in the phase plane is developed, and this theory predicts and explains the features seen in escape-time plots.
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27

Bodén, Roger. "Microactuators for Powerful Pumps". Doctoral thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9402.

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When paraffin wax melts it exhibits a large, relatively incompressible volume expansion. This can be used in microactuators for strong and large displacements, a rare combination among actuators. Furthermore, paraffin is inexpensive, inert and environmentally friendly, as well as easily processed and actuated. Together, these properties give paraffin actuators great potential for use in both low-cost and high-performance applications. In microfluidics, the miniaturization of various analysis systems decreases the volumes of samples and reagents needed, as well as the analysis throughput time. Using on-chip micropumps increases the efficiency of the microfluidic system, but a challenge for such pumps is the high back-pressure associated with separation, filtration or narrower channels. The objective of this thesis is to increase the understanding of paraffin in microactuators, as well as to further explore its possibilities and limitations. The main application area has been on-chip micropumps. For low-cost applications, actuators, pumps and dispensers have been fabricated in plastics and then evaluated. The dispenser is intended for on-chip storage and dispensing of liquids in a lab-on-a-chip that could be used in, e.g., point-of-care testing (POCT). For high-performance applications, metallic actuators, pumps and dispensers have been accomplished. The micropump is the world’s strongest mechanical micropump in sub-cubic centimetre size, capable of pressures of above 5 MPa. Possible applications are strong microhydraulics, on-chip chromatography, or medical microdosage systems. A limitation of paraffin is the relatively slow thermal actuation. In this thesis the thermal properties have also been turned into an advantage: Directional solidification is used to accomplish multiple stable states of the actuator displacement, withheld without any power consumption. For the future, the high-pressure capability may be improved by new designs. Optimization of speed and power consumption can be made by further work on modelling as well as on drive and control of the heating.
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28

Wu, Wei-Chung. "On-chip charge pumps". Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/13451.

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Stein, Richard J. B. "Roman wooden force pumps". Thesis, University of Reading, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444026.

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30

Valdeavellano, Francisca. "Pupa: herramienta para vendimiar". Tesis, Universidad de Chile, 2006. http://www.repositorio.uchile.cl/handle/2250/100914.

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31

Köpcke, Viviana. "Conversion of Wood and Non-wood Paper-grade Pulps to Dissolving-grade Pulps". Doctoral thesis, KTH, Träkemi och massateknologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-26967.

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Dissolving-grade pulps are commonly used for the production of cellulose derivatives and regenerated cellulose. To obtain products of high quality, these so-called "special" pulps must fulfill certain requirements, such as high cellulose content, low hemicellulose content, a uniform molecular weight distribution and high cellulose reactivity. Most, if not all, of the commercial dissolving pulps accomplish these demands to a certain extent. Nevertheless, achieving high cellulose accessibility as well as solvent and reagent reactivity is not an easy task due to the compact and complex structure presented by the cellulose. In the first part of this work, three commercial monocomponent endoglucanases were investigated with the purpose of enhancing the cellulose accessibility and reactivity of a hardwood dissolving pulp. A monocomponent endoglucanase with a cellulose-binding domain (CBD) was shown to significantly improve the cellulose reactivity. The positive effect of this enzyme on dissolving-grade pulps was also observed on paper-grade pulps. The main focus of the forest industry is the production of paper-grade pulps. Paper-grade pulps are mostly produced by the kraft process. In contrast, dissolving-grade pulps are produced by the sulfite and prehydrolysis kraft processes due to the high purity required for these pulps. The kraft process is known for being the most efficient process in terms of energy and chemical recovery, which makes the production costs of paper-grade pulps lower than those of sulfite dissolving-grade pulps. Besides, the production of dissolving pulps present, among others, higher capital and chemical costs than paper-grade pulps. Therefore, the viability of converting paper-grade pulps into dissolving pulps is brought into a question. However, this task is not simple because paper-grade pulps contain a lower cellulose content and a higher hemicellulose content than dissolving pulps. They also present lower cellulose reactivity and an inhomogeneous molecular weight distribution. As a consequence, the second part of this work focused on the study of the feasibility of converting kraft pulps into dissolving pulps. Several sequences of treatments of hardwoods and non-wood pulps were investigated. The best sequence for each suitable pulp was developed, and the parameters involved were optimized. After several attempts, it was demonstrated that pulps from birch, eucalypt and sisal fulfill the requirements of a commercial dissolving pulp for the viscose process after being subjected to a sequence of treatments that included two commercial enzymes, a xylanase and a monocomponent endoglucanase, and alkali extraction steps.
QC 20101201
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32

Oliveira, Luzia Pedroso de. "Modelos lineares mistos em estudos toxicológicos longitudinais". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/11/11134/tde-22042015-110346/.

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Os modelos mistos são apropriados na análise de dados longitudinais, agrupados e hierárquicos, permitindo descrever e comparar os perfis médios de respostas, levando em conta a variabilidade e a correlação entre as unidades experimentais de um mesmo grupo e entre os valores observados na mesma unidade experimental ao longo do tempo, assim como a heterogeneidade das variâncias. Esses modelos possibilitam a análise de dados desbalanceados, incompletos ou irregulares com relação ao tempo. Neste trabalho, buscou-se mostrar a flexibilidade dos modelos lineares mistos e a sua importância na análise de dados toxicológicos longitudinais. Os modelos lineares mistos foram utilizados para analisar os efeitos de dose no ganho de peso de ratos adultos machos e fêmeas, em teste de toxicidade por doses repetidas e também os efeitos de fase de gestação e dose nos perfis de pesos de filhotes de ratas tratadas. Foram comparados os modelos lineares mistos de regressão polinomial de grau 3, spline e de regressão por partes, ambos com um único ponto de mudança na idade média de abertura dos olhos dos filhotes, buscando o mais apropriado para descrever o crescimento dos mesmos ao longo do período de amamentação. São apresentados os códigos escritos no SAS/STAT para a análise exploratória dos dados, ajuste, comparação e validação dos modelos. Espera-se que o detalhamento da teoria e das aplicações apresentado contribua para a compreensão, interesse e uso desta metodologia por estatísticos e pesquisadores da área.
Mixed models are appropriate in the analysis of longitudinal, grouped and hierarchical data, allowing describe and compare the average response profiles, taking into account the variability and correlation among the experimental units of the same group and among the values observed over the time in the same experimental unit, as well as the heterogeneity of variances. These models allow the analysis of unbalanced, incomplete or irregular data with respect to time. This work aimed to show the flexibility of linear mixed models and its importance in the analysis of longitudinal toxicological data. Linear mixed models were used to evaluate the effects of doses in the body weight gain of adult male and female Wistar rats, in repeated doses toxicity test and also the effects of pregnancy period and dose in the pups growth of treated dams. It were compared the linear mixed models of third degree polynomial regression, spline and piecewise regression, both with a single point of change in the average time of pups eyes opening, searching for the most appropriate one to describe their growth along the lactation period. The SAS/STAT codes used for exploratory data analysis, comparison and validation of fitted models are presented. It is expected that the detailing of the theory and of the applications presented contribute with the understanding, interest and use of this methodology by statisticians and researchers in the area.
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Olmstead, Jennifer Anne. "Fluorescence spectroscopy of mechanical pulps". Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68232.

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Corrected steady-state fluorescence emission spectra of various mechanical pulps and celluloses were measured using an excitation wavelength of 320 nm. Regardless of its source, cellulose displayed a relatively high characteristic emission. The emission spectra of mechanical pulps were red-shifted with respect to that of cellulose, and peak shapes were influenced by the pulping process, by hydrogen peroxide bleaching and by monochromatic UV irradiation of the sheets. Changes in emission spectra due to bleaching or UV-irradiation occurred principally in the 370-440 and 500-550 nm regions, and were similar to changes in reflectance spectra reported in the literature. Fluorescence emission spectra of commercial lignins and lignin model compounds were blue-shifted with respect to mechanical pulps, even upon absorption of the fluorophores on solid substrates. Concentration and inner filter effects were evident in emission spectra of commercial lignins, at concentrations as low as 60 ppm. These results suggest that, to a first approximation, emission spectra of mechanical pulps may be interpreted as a decrease in emission of cellulose caused by light absorption by lignin; changes due to bleaching and irradiation may be attributed to changes in lignin absorption.
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Lindskog, Claes. "IC-påverkan av elektromagnetisk puls". Thesis, Linköping University, Department of Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15092.

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Detta examensarbete undersöker effekter av en elektromagnetisk puls på IC-kretsar.

För att kunna utvärdera inverkan har ett testobjekt, innehållande komponenter som skall testas, konstruerats. Detta testobjekt består av batteri, en enkel komponent och last. Ett pulsaggregat och en antenn användes för att generera de elektromagnetiska pulser som testobjektet utsattes för. Resultaten visar att inverkan på de testade komponenterna är möjlig. Inverkan visade sig vara beroende av bl.a. avståndet till antennen och den tid som testobjektet utsätts för störning. Störning har också utförts vid olika polariseringar.

Ett mål var att kunna jämföra en elektromagnetisk störning via en antenn med en trådbunden störning, där pulsen genererats från samma pulsaggregat. Försöken att utföra trådbunden störning av testobjektet misslyckades då pulsen inte var tillräckligt bra.

Detta examensarbete är en del av en artikel, High Power Ultra Wide Band and Vircator Source-Victim Experiment, som presenterades vid konferensen EMC Europe 2008.


This paper studies the effects of an electromagnetic pulse on IC-circuits. A DUT (device under test) has been constructed so that the effects of the pulse can be evaluated. The DUT consists of a battery, a load and the component, which is to be tested. A high voltage power supply and an antenna were used to generate the pulses that the DUT were exposed to. The results show that the effects were dependent on, among others, the distance between the antenna and the DUT and the time during which the DUT was exposed to the pulse. The DUT has also been exposed to different polarisations of the pulse.

One of the objectives of the study was to compare the difference between a pulse from an antenna and from a wire. This was to be done with the same high voltage power supply. Attempts to use a wire, for injecting the pulse, were unsuccessful since the damped pulse was not satisfying.

This paper is a part of a paper, High Power Ultra Wide Band and Vircator Source-Victim Experiment, that was presented at the conference EMC Europe 2008.

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Andreassen, Hanne Elisabeth Bø. "Air reversing CO2 heat pumps". Thesis, Norges Teknisk-Naturvitenskaplige Universitet, Institutt for elkraftteknikk, 2010. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-11017.

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CO2 is an environmentally friendly refrigerant that has a no global warming potential when used as refrigerant. The current refrigerants used for air conditioning in public transport are chemical components, and have a high global warming impact. The possibility of replacing the conventional refrigerants by CO2 is investigated for various parts of the transport sector. A possible CO2system for heating and cooling for public transport has been modeled and simulated. This system is a turntable prototype which is reversing the airflows to provide either cooling or heating. It has two gascoolers and two evaporators for separate treatment of ambient and recycled air. The plate is rotated 180˚ to switch from heating to cooling mode. CO2 has large potential for expansion work, due to the normally large throttling losses for high ambient temperatures. An ejector has therefore been implemented in the heat pump circuit. The turntable prototype is modeled by the simulation tool Modelica, and it is investigated how this ejector system adjusts to varying ambient conditions and power demand. Weather data from the climate database Meteonorm was used as a basis for calculation of heating and cooling demand for a train compartment in five different cities, covering a variety of climates. A case study was performed based on an occupancy rate profile and operative hours of the heat pump for the compartment. Simulations were performed of the air reversing heat pump based on the heating -and cooling demand calculations for the five cities. The COP values obtained are very positive, and they are in general higher for heating than cooling mode. The COP is depending on the load, and decreases with reduced occupancy rate. For cooling mode the COP ranged from 3.1 to 6. For heating mode it ranged from 8.2 to 2.8. With the occupancy rate chosen, the annual energy savings is about 80% for all the 5 cities of the study. The fan work of the heat pumps was also included for 4 different operating modes. This reduced the total COP by between 10 to 40%, depending on heating and cooling power requirement and ambient conditions. The fin and tube gas coolers that were used in the Modelica model were compared to a set of MPE gas coolers. The total mass of the heat exchangers was reduced by 50%. One would still have to weigh the reduced mass and increased LCCP performance against the increased investment cost of the MPE heat exchangers.

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Zora, Betul. "Ion pumps in Drosophila hearing". Thesis, The University of Iowa, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1601119.

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Ion pumps establish homeostasis across the membranes of living cells. Hearing is a mechanotransduction event that takes place in a closed compartment containing a fluid high in K+ concentrations. In Drosophila melanogaster, this closed compartment is formed by a scolopale cell that wraps around the dendrite of sensory neurons. The receptor lymph is maintained by the scolopale cell. The lumenal membrane of the scolopale cell is the wall of the compartment containing the receptor lymph, the scolopale space. The ablumenal membrane of the scolopale cell creates the border of the scolopidium.

The Na/K pump is located on the ablumenal membrane of the scolopale cell, bringing K+ into the scolopale cell cytoplasm and extruding K electrogenically (Roy et al., 2013). We explored other primary and secondary ion pumps that are involved in creating a K+-rich lumen in the Malpighian tubule (Day et al., 2008; Rodan et al., 2012). We used RNAi technology to knockdown one gene at a time and electrophysiology to measure a sound evoked potential (SEP) that reflects the fly’s ability to hear.

We found that knocking down V-ATPase, a proton pump, subunits involved in proton extrusion significantly reduces the SEP of knockdown flies. The involvement of cation chloride cotransporters (CCCs) and cation proton antiporter (CPAs), both secondary ion pumps that use the gradients created by the Na/K pump and V-ATPase respectively to pump other ions up their gradient, is less clear. We found that knocking down Nhe3, a CPA, significantly reduced the SEP when knocked down in the scolopale cell, suggesting it as a partner to the V-ATPase. Knocking down CG31547 statistically increased the SEP, possibly a type1 statistical error.

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Davies, Daniel Gower. "Modern wind powered water pumps". Thesis, University of Reading, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339497.

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Edwards, John Mason. "Microfluidic Electro-osmotic Flow Pumps". Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2145.pdf.

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Fuxová, Zuzana. "Online marketingová strategie Grandhotelu Pupp". Master's thesis, Vysoká škola ekonomická v Praze, 2014. http://www.nusl.cz/ntk/nusl-205115.

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The thesis analyses and evaluates a marketing strategy of the Grandhotel Pupp in comparison with its direct competitor, the Ambassador Grandhotel Narodni dum. The thesis focuses mainly on evaluating the online atributes of the marketing strategy including the online presentation of the hotel on all distribution channels the hotel uses. The main emphasis is put on current trends, because in marketing, these play the crucial role. First part of the thesis defines accommodation services, hospitality business specifics and specifics of marketing in hospitality. Second part evaluates the marketing techniques used on hotel s various distribution chanels. The second part then also compares all the activities used in marketing strategy of both above mentioned hotels.
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Wang, Longke. "Adaptive control of variable displacement pumps". Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/43654.

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Fluid power technology has been widely used in industrial practice; however, its energy efficiency became a big concern in the recent years. Much progress has been made to improve fluid power energy efficiency from many aspects. Among these approaches, using a valve-less system to replace a traditional valve-controlled system showed eminent energy reduction. This thesis studies the valve-less solution-pump displacement controlled actuators- from the view of controls background. Singular perturbations have been applied to the fluid power to account for fluid stiffness; and a novel hydraulic circuit for single rod cylinder has been presented to increase the hydraulic circuit stabilities. Recursive Least Squares has been applied to account for measurement noise thus the parameters have fast convergence rate, square root algorithm has further applied to increase the controller's numerical stability and efficiency. It was showed that this technique is consistent with other techniques to increase controller's robustness. The developed algorithm is further extended to a hybrid adaptive control scheme to achieve desired trajectory tracking for general cases. A hardware test-bed using the invented hydraulic circuit was built up. The experimental results are presents and validated the proposed algorithms and the circuit itself. The end goal of this project is to develop control algorithms and hydraulic circuit suitable for industrial practice.
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41

Rejman, Karl, i University of Lethbridge Faculty of Arts and Science. "What puts the 'terror' in terrorism". Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2003, 2003. http://hdl.handle.net/10133/232.

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How are we to combat terrosrism? Is terrorism ever morally justified? When is it rational to become a terrorist? What is so terrorizing about terrorism? The answers to these important questions depend on the most fundamental one: what is terrorism? In this thesis I utilize a practice analysis to discover how we in the West think about war. From that analysis, a definition of terrorism, captured in military categories, is offered. This definition is then used to discover what makes terrorism so terrifying for us. Finally, the definition of terrorism argued for in this thesis is tested for its applicability to further analysis by using the definition to analyze the current Israeli-Palestinian conflict, the Pentagon and World Trade Center attacks on events of September 11th, and nuclear deterrence.
vi, 86 leaves ; 29 cm.
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42

Lee, Hi Sun. "Spray generation by gas-lift pumps". Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61897.

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43

Tomac, Tom, i n/a. "Feedback and control of micro-pumps". Swinburne University of Technology, 2006. http://adt.lib.swin.edu.au./public/adt-VSWT20070220.130359.

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This thesis constitutes the documentation for a Doctoral research program undertaken at the Industrial Research Institute of Swinburne University of Technology (IRIS) between 2001 and 2005. The focus of the research was an investigation of the open- and closed-loop response of piezoelectric micro-pumps for micro-fluidic applications, particularly for chemical and biomedical environments. Specifically, in order to successfully integrate micro-devices into functional systems, it was important to address issues of real-time performance monitoring and control. The research addresses some of these problems in the context of a piezoelectric-driven micro-pump, equipped with interferometric displacement feedback, which was used to measure the dynamic displacement of the micro-pump actuator surface. During the course of the research, both a discrete component and a fully integrated (laboratory-on-a-board) test system were developed for open-loop characterization of the micro-pump. The laboratory-on-a-board system was also used for closed-loop control application. Measurements showed significant differences in actuator velocity, displacement and settling time between different pumping media. In addition, transient underdamped vibration of the actuator surface was observed during the rapid excursion and recursion phases of the pump movement while pumping air. These non-contact measurements could be used to determine the open-loop characteristics of a micropump and provide information for design improvement or failure detection/analysis. The technique could also be used to provide continuous measurement for adaptive compensation, so that the pump performance criteria are always satisfied. To this end, an automated interference fringe counting algorithm was developed, so that the steadystate parameters could be mapped into the closed-loop control elements in real time. The performance of this algorithm is discussed herein, together with the implications for optimal control of the micro-pump, and eventual integration of the interferometer and micro-pump systems. The research indicated that there were potential benefits in closed-loop control of micro-pumps, particularly where failure detection was required and for pumping of non-homogeneous media. The thesis also documents the relative performance differences between open and closed-loop control in homogenous media.
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Welch, Lorrie V. S. "Low-consistency refining of mechanical pulps". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0014/NQ38999.pdf.

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Krishnan, Sundar. "Improvement in bleaching of mechanical pulps". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0031/MQ65498.pdf.

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46

Wiklund, Pär-Eric. "Suction dynamics of axial piston pumps /". Stockholm, 1998. http://www.lib.kth.se/abs98/wikl0511.pdf.

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Tomac, Tom. "Feedback and control of micro-pumps". Australian Digital Thesis Program, 2006. http://adt.lib.swin.edu.au/public/adt-VSWT20070220.130359/index.html.

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Thesis (PhD) - Swinburne University of Technology, Industrial Research Institute Swinburne - 2006.
A thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy in the school of Advanced Studies at Industrial Research Institute Swinburne, Swinburne University of Technology - 2006. Typescript. "December 2006". Includes bibliographical references (p. 233-242).
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Robbie, M. J. "Regenerative pumps for aircraft fuel systems". Thesis, Cranfield University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359572.

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Diaz, Gómez Maqueo Pablo (Pablo Ly). "Electrospray emitters For diffusion vacuum pumps". Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/67181.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2011.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 85-87).
Following similar principles as regular diffusion vacuum pumps, an electrospray emitter is set to produce a jet of charged particles that will drag air molecules out of a volume. To be a feasible concept, the emitted particles should have enough momentum to make the colliding air particles being effectively removed from the volume. Also the density of the droplets should be such that the mean free path of air molecules to electrosprayed droplets is in the order of magnitude of the testing setup. A theoretical model is developed for estimating the pumping speed and the importance of the conductivity of the working fluid is identified. Experimental results show an interesting effect. as the pressure difference between two volumes separated by an aperture, is reduced when an electrospray emitter is on. It is showed that a single emitter is expected to have a very low pump capacity, so an array of emitters is proposed as solution. This thesis also comments on the applicability of powder compression molding for the fabrication of emitter arrays. Powder compression molding consists in manufacturing the emitter array out of a plastic - metallic powder feedstock. It consists on 4 steps: (1) Mixing of feedstock, (2) Compression molding, (3) Debinding and (4) Sintering. Initial experiments on compression molding are successful in reproducing arrays of micropillars.
by Pablo Diaz Gomez Maqueo.
S.M.
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Hannour, Samir. "Synthèse d'alpha-aminoacides phosphoniques énantiomériquement purs". Montpellier 2, 1995. http://www.theses.fr/1995MON20104.

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Les alpha-aminoacides phosphoniques ainsi que leurs derives les phosphono peptides suscitent un interet grandissant grace a leurs applications. Ils ont fait l'objet ces dernieres annees, de nombreuses recherches et ont donne lieu a plusieurs publications. Les aminoacides phosphoniques presentent d'importantes proprietes biologiques en tant qu'inhibiteurs d'enzymes, neuromodulateurs, herbicides, antibacteriens, agents anticancereux et antihypertensifs l'activite biologique depend non seulement de la structure mais aussi de la chiralite, c'est la raison pour laquelle nous nous sommes interesses a la synthese asymetrique d'alpha-aminoacides phosphoniques. Notre travail a pour but la synthese de nouveaux aminoacides phosphoniques enantiomeriquement purs en utilisant la methode d'alkylation de bases de schiff chirales, l'auxiliaire chiral etant la 2-hydroxypinan-3-one, developpee dans notre laboratoire. Ainsi nous avons obtenu les analogues phosphoniques de la leucine de l'homotryptophane de l'homoserine et de l'acide 3,4-methanoglutamique. L'analogue phosphonique de l'homoserine s'est revele un synthon de choix pour l'obtention de divers aminoacides phosphoniques difficilement accessibles par d'autres methodes: les analogues phosphoniques de l'homophenylalanine, de l'acide homoquisqualique, de l'acide 2,4 diaminobutyrique (daba) et de la vinyl glycine
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