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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Sistematica molecular e variação morfometrica da asa de especies de Drosophila da radiação tripunctata / Molecular systematics and wing morphometric variation in species of the Drosophila tripunctata radiation

Hatadani, Luciane Mendes 26 November 2007 (has links)
Orientadores: Louis Bernard Klaczko, Ana Maria L. Azeredo-Espin / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-10T12:39:08Z (GMT). No. of bitstreams: 1 Hatadani_LucianeMendes_D.pdf: 5098763 bytes, checksum: ffd29b437b2e422e6d8f1797873032be (MD5) Previous issue date: 2007 / Resumo: O grupo tripunctata e o segundo maior grupo neotropical de Drosophila em numero de espécies e foi incluído na radiação tripunctata ¿ que inclui outros grupos próximos. O segundo cromossomo de Drosophila medipunctata (espécie que pertence ao grupo tripunctata) e altamente polimorfico para inversões. Trabalhos anteriores sugeriram a presença de interação genotipo-ambiente para tamanho da asa, mas não para forma. Experimentos de laboratório foram realizados para testar os efeitos combinados de temperatura e inversão cromossômica no tamanho e forma da asa de D. mediopuncta. A morfologia da asa foi analisada por métodos de morfometria geométrica. Os resultados mostraram que tamanho e forma da asa são influenciados por temperatura, sexo e cariótipo. Também foram encontradas evidencias que sugeriram a existência entre os efeitos de cariótipo e temperatura para forma da asa, mas nao para tamanho, indicando a presença de interação genotipo-ambiente para forma da asa em D. mediopunctata. Sugerimos que outros fatores ecológicos ¿ tais como densidade de larvas ¿ ou variação sazonal de conteúdo genético das inversões poderia explicar os resultados anteriores. Alem disso, uma nova hipótese filogenética para a radiação tripunctata e sugerida com base em dados de seqüências dos genes mitocôndrias das subunidades I e II da citocromo oxidase, e a variação de tamanho e forma da asa e descrita com bases na nova hipótese filogenética. As arvores filogenéticas foram reconstruídas por métodos de parcimônia, máxima verossimilhança e inferência Bayesiana. Os resultados rejeitaram a hipótese de monofila para o grupo tripunctata, enquanto esta hipótese não foi rejeitada para a radiação tripunctata e outros grupos específicos dentro da radiação. Ambos tamanho e forma da asa apresentaram sinal filogenético e diferentes padrões de tamanho e forma puderam ser identificados para cada um dos agrupamentos mais importantes detectados pela analise filogenética / Abstract: The tripunctata group is the second largest Neotropical group of Drosophila in number of species and was included in the tripunctata radiation ¿ which comprises other closely related groups. The second chromosome of Drosophila mediopunctata (a species that belongs to the tripunctata group) is highly polymorphic for inversions. Previous work suggested the presence of genotype-environment interaction for wing size but not for shape. We performed experiments in the laboratory to test for the joint effects of temperature and chromosome inversions on size and shape of the wing in D. mediopunctata. Wing morphology was analyzed by methods of geometric morphometrics. Our findings show that wing size and shape are influenced by temperature, sex, and karyotype. We also found evidence suggestive of an interaction between the effects of karyotype and temperature on wing shape (but not for size), indicating the existence of genotype-environment interaction for wing shape in D. mediopunctata. We suggest that other ecological factors ¿ such as larval crowding ¿ or seasonal variation of genetic content within inversions may explain the previous results. Moreover, we suggest a new phylogenetic hypothesis for the tripunctata radiation based on sequences of mitochondrial genes of cytochrome oxidase subunits I and II, and describe wing size and shape variation in different species based on this new phylogenetic hypothesis. Phylogenetic trees were reconstructed by parsimony, maximum likelihood and bayesian inference. Results reject the monophyly hypothesis for the tripunctata group whereas monophyly is not rejected for the tripunctata radiation and other specific groups within the radiation. Both wing size and shape displayed phylogenetic signal and different patterns of size and shape could be identified for each of the most important clusters detected by phylogenetic analysis / Doutorado / Genetica Animal e Evolução / Doutor em Genetica e Biologia Molecular
272

Ocorrência de fogachos e sua relação com os ritmos circadianos de temperatura periférica do punho, atividade/repouso e estados de humor em mulheres na pós-menopausa. / Hot flashes episodes and the circadian rhythms of wrist temperature, rest/activity and mood in post-menopausal women.

Hadassa Batinga da Silva 16 December 2009 (has links)
O objetivo do trabalho foi verificar possíveis relações entre a ocorrência dos fogachos e as oscilações da temperatura periférica, atividade motora e do humor. Participaram do protocolo 19 pacientes do Hospital das Clínicas de São Paulo, separadas em 2 grupos: mulheres pós-menopausa com fogachos e mulheres pós-menopausa sem fogachos, mais o grupo controle. As variáveis coletadas foram: a atividade motora do braço, temperatura da pele do punho e ocorrência de fogachos. Encontramos ritmicidade circadiana significativa na ocorrência de fogachos em 5 voluntárias e ritmicidade infradiana significativa (períodos entre 7 e 14 dias) em 4 voluntárias. Observamos correlação positiva entre essa pontuação do questionário de cronotipo e a amplitude da curva ajustada do ritmo de temperatura punho e correlação positiva entre fogachos e a média da temperatura do punho. A média da temperatura do punho das mulheres com fogachos foi maior que a das mulheres sem fogachos e controles. Na população estudada demonstramos evidências de relações entre os episódios de fogachos e as oscilações da temperatura periférica, atividade motora. Não encontramos relações significativas entre a ocorrência de fogachos e variações dos estados de humor alegria e ansiedade. / In this study we evaluated possible correlations between peripheral (wrist) temperature, rest/activity and mood circadian rhythms and the occurrence of hot flashes in post-menopausal women. Nineteen patients from Hospital das Clínicas de São Paulo had participated this study. The patients were separated in 2 groups: post-menopausal women with hot flashes (n=13) aged 55±4; postmenopausal women without hot flashes (n=6) with 59±1.51 years old, besides the control group (n=10) with 36±4 years old. The data collected were motor activity of the arm, peripheral (wrist skin) temperature and occurrence of episodes of hot flashes. Volunteers wore actimeters to collect motor activity data and wrist temperature along 30 consecutive days and filled sleep diaries and two visual analogue scales (anxiety and joy) for mood self-evaluations every three hours and during the hot flashes. All volunteers filled the chronotype questionnaire (QC). We found significant (p<0.05) circadian rhythmicity of hot flashes occurrence in 5 women and significant (p<0.05) infradian rhythmicity (periods between 7 and 14 days) in 4 women; positive correlation between QC scores and total number of hot flashes (r=0.424; p<0.05). We also observed positive correlation between the QC score and the amplitude of the fitted curve of peripheral temperature rhythm (r= 0.628; p<0.01) and positive correlation between total number of hot flashes and mean value of wrist temperature (r=0.505;p<0.05). The mean value of peripheral temperature of postmenopausal women with hot flashes was higher than that for post-menopausal women without hot flashes and control group (p<0.036, Kruskal-Wallis test). We found an increase (p< 0.001, Mann-Whitney test) in mean wrist temperature within 15 minutes of hot flashes. The occurrence of hot flashes tends to be concentrated between the evening and sleep onset for most of the women who referred hot flashes. We have demonstrated some evidences of relationships between episodes of hot flashes and the peripheral temperature and motor activity oscillations. We have not found significant relations between the occurrence of hot flashes and mood oscillations as measured for the states of anxiety and joy.
273

Ritmos biológicos em índios Guarani adultos / Biological rhythms in Guarani adult indians

Daniela Wey Camilo Lapa 04 December 2007 (has links)
Comunidades que vivem em regiões sem energia elétrica apresentam suas atividades sincronizadas pelo ciclo dia/noite e por compromissos sociais podendo haver uma diferença sazonal no comportamento. No ambiente urbano a energia elétrica cria a possibilidade de nos organizarmos temporalmente de acordo com os nossos interesses. Este comportamento tem sido apontado como uma das causas para a ausência de sazonalidade nos ritmos biológicos humanos. Este estudo fenomenológico naturalístico em índios Guarani que viviam em casas sem energia elétrica nos permitiu refletir sobre a presença de sazonalidade nos ritmos biológicos. O ritmo de temperatura do punho em 21 índios e o ciclo de atividade/repouso em 16 índios foram comparados entre o inverno e verão. O perfil temporal da temperatura não se alterou nas duas épocas, mas houve diferença nos valores de amplitude e MESOR que pode ser explicada pela variação sazonal do padrão de dissipação de calor através da pele. Não houve diferença entre o inverno e verão para os valores de acrofase, e os índios mais novos apresentaram horários de acrofase da temperatura mais tardios que os índios mais velhos. Do inverno para o verão observamos um atraso nos horários de repouso sem alteração significativa na duração. Não verificamos diferença nos horários e na duração do repouso entre os dias de semana e fins de semana. O padrão de atividade/repouso não apresentou relação com a duração/alocação da noite no inverno e verão e houve uma correlação negativa com os valores de temperatura do punho. Os índios adultos da Aldeia Boa Vista apresentam ritmos biológicos com características típicas de uma comunidade de transição. As atividades na aldeia são sincronizadas pelas diferentes relações sociais que se estabelecem em cada época do ano. / Communities living in areas without electricity present biological rhythms synchronized by the day/night cycle and social schedules; it seems possible to detect seasonal differences in their behaviour. In urban areas electricity allow us to organize our activities according to our interests. This behaviour has been pointed as a cause for the absence of seasonality in human biological rhythms. The present naturalistic phenomenological study of Guarani indians that living in no electricity houses allowed us to think about the presence of seasonality in biological rhythms. Wrist temperature and activity/rest rhythms of 21 indians were compared between winter and summer. The temperature profile did not change, but a seasonal difference was found for amplitude and MESOR values which may be related to metabolic-behavioral processes involved in thermoregulation. In summer the vasodilation is intense and the heat dissipation is maximum (with low variability), the opposite tends to occur in winter. We did not find seasonality in acrophase values between subjects, and we also found the same correlation described for urban populations: a phase advance of body temperature in the elderly. From winter to summer the onsets/offset of rest were delayed, with no change in rest duration. For the indians there was no difference in the schedules of rest/activity during the week. The activity/rest cycle was not determined by the day/night cycle but showed a significant correlation with wrist temperature. The adult indians of Boa Vista settlement showed typical characteristics in their biological rhythms of a transition community. The activities in the settlement are synchronized by singular relationships that take place in each season.
274

Influência do ciclo reprodutivo na biologia termal de Crotalus durissus neotropical (Serpentes, Viperidae) em cativeiro / Influence of the reproductive cycle on the thermal biology of Crotalus durissus Neotropical (Serpentes, Viperidae) in captivity

Patricia da Silva Marinho 01 September 2017 (has links)
As serpentes são animais ectotérmicos capazes de modificar seu comportamento termorregulatório e consequentemente sua temperatura corpórea para otimizar o desempenho de determinadas atividades, dentre elas, a reprodução. Segundo vários estudos, a reprodução é um dos fatores fisiológicos mais influenciados pela seleção de temperatura corpórea em Squamata. Fêmeas reprodutivas de muitas espécies têm apresentado termofilia gestacional. Esse comportamento tem corroborado a hipótese de manipulação materna da temperatura ótima para o desenvolvimento embrionário, com isso, a fêmea garante o fenótipo da prole e seu sucesso reprodutivo. Aqui investigamos a influência do status reprodutivo na biologia termal de fêmeas de Crotalus durissus em cativeiro semiextensivo. Para isso, foram utilizados sensores de temperatura interna (datalogger) inseridos cirurgicamente na cavidade celomática de fêmeas prenhes e não prenhes. As análises dos dados demonstraram que fêmeas prenhes mantiveram a média de temperatura corpórea significativamente mais elevadas do que fêmeas não prenhes no verão. No entanto, a variação da Tc de fêmeas prenhes não difere de fêmeas não prenhes. O benefício mais frequentemente citado sobre a evolução da viviparidade, é que fêmeas prenhes podem acelerar o desenvolvimento embrionário por meio da termorregulação. A elevação e estabilidade da temperatura corpórea durante a gestação têm sido consideradas o mecanismo primordial para assegurar o desenvolvimento embrionário. Desta forma, aumenta o fitness da prole e garante a viabilidade da ninhada. Os dados apresentados aqui demonstram que a condição reprodutiva de fêmeas prenhes de Crotalus durissus tem grande influência sobre a seleção de temperaturas mais elevadas, corroborando com a hipótese de que fêmeas alteram o comportamento termorregulatório quando estão prenhes. / Snakes are ectothermic animals capable of modifying their thermoregulatory behavior and consequently their body temperature to optimize the performance of certain activities, among them, reproduction. According to several studies, reproduction is one of the physiological factors most influenced by the selection of body temperature in Squamata. Reproductive females of many species have shown gestational thermophily. This behavior has corroborated the hypothesis of maternal manipulation of the optimum temperature for embryonic development, therefore, the female assures the phenotype of offspring and their reproductive success. Here we investigate the influence of reproductive status on the thermal biology of Crotalusdurissus females in semiextensive captivity. For this, internal temperature sensors (dataloggers) were inserted surgically in the coelomic cavity of pregnant and non-pregnant females. Data analyzes demonstrated that pregnant females maintained significantly higher mean body temperature than non-pregnant females in the summer. However, the body temperature variation of pregnant females does not differ from non-pregnant females. The most frequently cited benefit on the evolution of viviparity is that pregnant females can accelerate embryonic development through thermoregulation. The elevation and stability of body temperature during pregnancy have been considered the primordial mechanism to ensure the embryonic development. Thus, it increases the fitness of offspring and ensures the viability of the clutch. The data presented here, demonstrate that the reproductive condition of pregnant females of Crotalus durissus has great influence on the selection of higher temperatures, corroborating with the hypothesis that females alter the thermoregulatory behavior when they are pregnant.
275

Human cold exposure, adaptation and performance in a northern climate

Mäkinen, T. M. (Tiina M.) 23 May 2006 (has links)
Abstract The purpose of the study was to examine the amount of cold exposure and factors affecting it at the population level in Finland, to determine what type of cold acclimatisation, if any, develops in urban residents in winter, and to find out whether cold acclimatisation or acclimation has a functional significance on psychological or physical performance. Tasks of low physical activity requiring attention and concentration (cognition, postural control) were assessed in cold. In a cross-sectional population study Finns aged from 25 to 74 years (n=6,951) were queried of their wintertime outdoor exposure duration and factors affecting it. In experimental studies seasonal cold acclimatisation (thermal responses) and its effect on cognition were assessed in the laboratory, where 15 young urban subjects were exposed to cold in winter and summer in bright or dim light. A controlled cold acclimation trial (n=10) was performed to study the effects of repeated exposures to cold on cognitive performance and postural control in young urban subjects. In the Finnish population the average amount of cold exposure in winter represents 4% of the total time. Most of the cold exposure occurs during leisure time and in outdoor occupations (agriculture, forestry, mining, industry, construction). Factors explaining increased occupational cold exposure were: occupation, age and a lesser amount of education. Factors associated with more leisure-time cold exposure were: being employed in outdoor occupations, being a pensioner, housewife, unemployed, practising physical exercise, and reporting at least average health. The experimental studies showed seasonal differences and aggravated thermal responses in urban residents in winter, but did not detect habituation responses typical of cold acclimatisation. In both seasons, acute moderate cold exposure resulted in positive, negative or mixed effects on cognition, reflected as changes in response times and accuracy. Simple cognitive tasks were impaired in cold, and in complex tasks both negative, positive and mixed effects were observed. It is suggested that cold exposure affects cognition through different mechanisms related to either distraction or arousal. Cold exposure increased postural sway by 70-90%, suggesting impaired postural control. Repeated exposures to moderate cold, reducing stress and discomfort and dampening physiological responses, did not markedly affect cognitive performance or postural control.
276

Thermal, circulatory, and neuromuscular responses to whole-body cryotherapy

Westerlund, T. (Tarja) 17 March 2009 (has links)
Abstract The purpose of this study was to examine thermal (body temperature, thermal sensation and comfort ratings), circulatory (blood pressure, heart rate variability) and neuromuscular performance responses to whole-body cryotherapy (WBC, -110 °C). Altogether 66 healthy subjects were exposed to WBC for two minutes. The acute and long-term changes were examined, when the subjects were exposed to WBC three times a week during three months. Skin temperatures decreased very rapidly during WBC, but remained such a high level that there was no risk for frostbites. The effects on rectal temperature were minimal. Repeated exposures to WBC were mostly well tolerated and comfortable and the subjects became habituated at an early stage of trials. WBC increased both systolic (24 mmHg) and diastolic (5 mmHg) blood pressures temporarily. Adaptation of blood pressure was not found during three months. The acute cooling-related increase in high-frequency power of RR-intervals indicated an increase in cardiac parasympathetic modulation, but after repeated WBC the increase was attenuated. The repeated WBC exposure-related increase in resting low frequency power of RR-intervals resembles the response observed related to exercise training. There are signs of neuromuscular adaptation, especially in dynamic performance. A single WBC decreased flight time in drop-jump exercise, but after repeated WBC these changes were almost vanished. This adaptation was confirmed by the change of the activity of the agonist muscle, which increased more and the change of the activity of antagonist muscle, which increased less/did not change after repeated WBC indicating reduced co-contraction and thus, neuromuscular adaptation.
277

Automatic Features Identification with Infrared Thermography in Fever Screening

Surabhi, Vijaykumar January 2012 (has links)
The goal of this thesis is to develop an algorithm to process infrared images and achieve automatic identification of moving subjects with fever. The identification is based on two main features: the distinction between the geometry of a human face and other objects in the field of view of the camera, and the temperature of the radiating object. Infrared thermography is a remote sensing technique used to measure temperatures based on emitted infrared radiation. Applications include fever screening in major public places such as airports and hospitals. Current accepted practice of screening requires people to stay in a line and temperature measurements are carried out for one person at a time. However in the case of mass screening of moving people the accuracy of the measurements is still under investigation. An algorithm constituting of image processing to threshold objects based on the temperature, template matching and hypothesis testing is proposed to achieve automatic identification of fever subjects. The algorithm was first tested on training data to obtain a threshold value (used to discriminate between face and non face shapes) corresponding to a false detection rate of 5%, which in turn corresponds to 85% probability of detection using Neyman-Pearson criterion. By testing the algorithm on several simulated and experimental images (which reflect relevant scenarios characterizing crowded places) it is observed that it can be beneficially implemented to introduce automation in the process of detecting moving subjects with fever.
278

Errors in skin temperature measurements.

Dugay, Murielle 12 1900 (has links)
Numerical simulation is used to investigate the accuracy of a direct-contact device for measuring skin-surface temperature. A variation of thermal conductivity of the foam has greater effect on the error rather than a variation of the blood perfusion rate. For a thermal conductivity of zero, an error of 1.5 oC in temperature was identified. For foam pad conductivities of 0.03 and 0.06 W/m-oC, the errors are 0.5 and 0.15 oC. For the transient study, with k=0 W/m-oC, it takes 4,900 seconds for the temperature to reach steady state compared with k=0.03 W/m-oC and k=0.06 W/m-oC where it takes 3,000 seconds. The configuration without the foam and in presence of an air gap between the skin surface and the sensor gives the most uniform temperature profile.
279

Temperature Biofeedback and Visual Imagery in the Treatment of Migraine Headaches

Clark, Susan Matthews 12 1900 (has links)
After an initial four week baseline period, during which headache activity and medication consumption were monitored, 28 migraineurs were randomly assigned to one of the following groups: (a) the biofeedback temperature warming group, (b) the visual imagery group, (c) the combined treatment group, or (d) the comparison group. All four groups continued to monitor their headache activity and medication consumption during the eight week treatment period and the eight week follow-up period. A two way analysis of variance computed on groups over time indicated a significant decrease in headache activity and medication consumption. During the follow-up period (a) the combined treatment group had significantly fewer headaches than the biofeedback group or the comparison group and (b) the visual imagery group and the combined treatment group had significantly fewer headache hours than the biofeedback group or the comparison group. These results do not appear to be attributable to differences between groups on the amount of time spent in home practice or subjective ratings of relaxation. There was no consistent relationship between increases in finger temperature and headache activity improvement. Decreases in powerful other scores, as measured by the Health Attribution Test, and increases in subjective ratings of internal control were consistent with a reduction in headache activity and medication consumption.
280

Identification of Common and Separate Mechanisms Governing Circadian Locomotor Activity and Body Temperature / 行動と体温の概日変動を支配する共通および個別メカニズムの同定

Shimatani, Hiroyuki 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(薬科学) / 甲第23142号 / 薬科博第141号 / 新制||薬科||15(附属図書館) / 京都大学大学院薬学研究科医薬創成情報科学専攻 / (主査)教授 土居 雅夫, 教授 中山 和久, 教授 竹島 浩 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM

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