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Submitted by Rodolfo César de Oliveira Anderson null (rco.anderson@gmail.com) on 2017-09-12T12:04:57Z No. of bitstreams: 1 Dissertação_final.pdf: 1603715 bytes, checksum: 0b40e4e5998ff7807dd5b93ea532c5fa (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-09-12T17:51:42Z (GMT) No. of bitstreams: 1 anderson_rco_me_rcla.pdf: 1603715 bytes, checksum: 0b40e4e5998ff7807dd5b93ea532c5fa (MD5) / Made available in DSpace on 2017-09-12T17:51:42Z (GMT). No. of bitstreams: 1 anderson_rco_me_rcla.pdf: 1603715 bytes, checksum: 0b40e4e5998ff7807dd5b93ea532c5fa (MD5) Previous issue date: 2017-08-09 / Devido à alta permeabilidade da pele e a ectotermia, anfíbios terrestres são confrontados por compromissos envolvendo o balanço de água e a regulação da temperatura corpórea. O modo como tais compromissos são acomodados, sobre uma extenção de temperaturas e estados de hidratação, influencia importantemente o comportamento e a ecologia desses animais. Nesse contexto, usando o anfíbio terrestre Rhinella schneideri como organismo modelo, os objetivos do presente estudo foram duplos. Primeiramente, nós determinamos como a sensibilidade termal de uma característica ecologicamente relevante – a locomoção – é afetada pela desidratação. Além disso, nós examinamos os efeitos dos mesmos níveis de desidratação na preferência termal e na tolerância termal. A medida que a desidratação se torna mais severa, as temperaturas ótimas para o desempenho locomotor diminuíram e a amplitude de temperaturas para um desempenho próximo ao máximo se estreitou. Semelhantemente, a desidratação foi acompanhada por uma diminuição da amplitude de tolerância termal. Tal declínio foi causado pelo aumento da temperatura crítica mínima e pela diminuição da temperatura crítica máxima, com este último mudando de modo mais acentuado. Em geral, nossos resultados mostram que os efeitos negativos da desidratação no desempenho comportamental e na tolerância termal são, ao menos parcialmente, amenizados pelo simultâneo ajuste na preferência termal. Nós discutimos algumas potenciais implicações dessa observação para a conservação dos anfíbios anuros. / Due to their highly permeable skin and ectothermy, terrestrial amphibians are challenged by compromises between water balance and body temperature regulation. The way in which such compromises are accommodated, under a range of temperatures and dehydration levels, impact importantly the behavior and ecology of amphibians. Thus, using the terrestrial toad Rhinella schneideri as a model organism, the goals of the present study were two-fold. First, we determined how the thermal sensitivity of a centrally relevant trait – locomotion – was affected by dehydration. Secondly, we examined the effects of the same levels of dehydration on thermal preference and thermal tolerance. As dehydration becomes more severe, the optimal temperature for locomotor performance was lowered and performance breadth narrower. Similarly, dehydration was accompanied by a decrease in the thermal tolerance range. Such a decrease was caused by both, an increase in the critical minimal temperature and a decrease in the thermal maximal temperature, with the latter changing more markedly. In general, our results show that the negative effects of dehydration on behavioral performance and thermal tolerance are, at least partially, counteracted by concurrent adjustments in thermal preference. We discuss some of the potential implications of this observation for the conservation of anuran amphibians.

published_or_final_version / abstract / Physics / Doctoral / Doctor of Philosophy

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Call number: LD2668 .T4 1958 F58 / Master of Science

In the first part of the thesis, we investigate ground state properties of Tonks-Girardeau(TG) gas in an one-dimensional periodic trap. The key issue we are interested in is whether periodically-trapped TG gas has an off-diagonal long range order. Through numerical calculations, the single-particle reduced density matrix is computed for systems with up to 265 bosons. Scaling analysis on the occupation number of the lowest orbital shows that there is no Bose-Einstein condensation for the periodically-trapped TG gas in both commensurate and incommensurate cases. We find that, for the commensurate case, the scaling exponents of the occupation number of the lowest orbital, the amplitude of the lowest orbital and the zero-momentum peak height with the particle numbers are 0, 0.5 and 1, respectively, while for the incommensurate case, they are 0.5, 0.5, and 1.5, respectively. These exponents are related to each other by a universal relation. / In the second part we study the one-dimensional "hard-sphere" fermions and bosons systems. The pair distribution functions of the one-dimensional "hard-sphere" fermions and bosons systems have been exactly evaluated by introducing gap variables. Some interesting results are obtained. Meanwhile, the pair distribution function could be measured in experiments, so hopefully our numerical results may be observed experimentally in the near future. / Lastly, we investigate the one-dimensional multi-component fermions and bosons systems. This is an extension of the work of C.N.Yang and Y.Z.You in 2011. Yang and You studied the ground state energy of w-component fermions and bosons with repulsive interactions. In this part, we investigate w-component fermions and bosons in an attractive interaction regime. Several theorems about the ground state energy of w-component fermions and bosons systems are stated and proved. Combing the results in the work of Yang and You, we finally have a comprehensive picture for the ground state energy of one-dimensional fermions and bosons systems. iii / Over the last ten years or so, there have been a number of dramatic experimental developments in trapping, cooling and controlling atoms, which open up new opportunities for studying strongly interacting many-body systems. Cold atom systems are very clean and highly tunable. Systems with different dimensionalities can be realized through optical lattice confinement, and the interactions between atoms can be fine-tuned to any value desired by Feshbach resonance. In this way various simple models can be realized to analyze subtle many-body problems which are difficult to analyze because of the complexity of the systems in real materials. / Wei, Bobo = 一維超冷原子系統中的多體物理 / 魏勃勃. / Adviser: Hai Qing Lin. / Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 76-[80]). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Wei, Bobo = Yi wei chao leng yuan zi xi tong zhong de duo ti wu li / Wei Bobo.

Ma, Kwok Wai = 相互作用的超冷原子於一維系統之有關課題 / 馬國威. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 69-74). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese. / Ma, Kwok Wai = Xiang hu zuo yong de chao leng yuan zi yu yi wei xi tong zhi you guan ke ti / Ma Guowei.

This thesis is divided into two parts. In Section I a description is given of a liquid hydrogen bubble chamber expansion system designed for use with the Imperial College 40cm. hydrogen chamber, and as a prototype system for the 150 cm. British National chamber. Section II contains a study of - proton interactions at an incident pion momentum of 4 Gev/c. The Saclay 81cm. liquid hydrogen bubble chamber was exposed to a beam from the CERN proton synchroton, and produced 60,000 useful pictures. The analysis of those events with two charged secondaries, excluding strange particle events, is presented. Chapter II reviews the background to and objectives of the experiment. In Chapter III an account is given of the apparatus and methods used in the processing of the film. The individual identification of events is described in Chapter IV. Cross-sections, angular and momentum distributions, and resonance production for the different reaction channels are presented and discussed in Chapters V and VI. Finally in Chapter VII, a brief description is given of some preliminary results of an investigation of +-proton interactions of 4Gev/c.

The aim of this study was to clarify the relationship between the dosage parameters and temperature increase at the target tissues (up to 5 cm below the skin surface), and to explore the possibility of proposing a preliminary model to guide clinicians and researchers in determining treatment dosages based on expected increase in temperatures at the target tissue. Prior to the conduct of the main study several protocol-related issues were investigated. These included the reliability of the measurement procedures, the optimum speed of movement of the transducer, the optimum size of the treatment area, and the maximum output intensity that could be considered safe for treatment applications and investigations. An in-vitro post-mortem pig model was chosen for the experimental design using only adult-sized pigs, weighing between 60 to 80 kilograms. A total of 76 specimens were obtained from the shoulder and thigh sections of 19 pigs. The therapeutic ultrasound machine used throughout the study was the Omnisound 3000TM (Physio Technology Inc., Topeka, Kansas, USA) Output from the Omnisound 3000TM was checked and calibrated as necessary prior to each experiment using a power meter (Model UPM-DT-10, Ohmnic Instruments Co., St. Michaels, Maryland 21663, USA). Calibration was only performed when the checks demonstrated an error in the output intensity of the machine exceeded ±10%. The Minolta spot thermometer (HT-11, Minolta Co. Ltd., Japan) and the Avio thermal video system (TVS) 2000TM (Nippon Avionics Co. Ltd., Japan) were used to measure the change in tissue temperatures (dependent variable) at the skin surface and subcutaneously (at l, 2, 3, 4 and 5 cm below skin surface) respectively. The prepared specimen was mounted on a fixed table, with the clean cross-section facing the infrared thermographic camera. / The camera to specimen distance was standardised at 50 cm for all experiments. Markers corresponding to 1, 2, 3, 4, and 5 cm on the specimen were plotted on the display unit, and saved to a 3.5 inch floppy disk. Measurements were recorded at baseline (prior to commencement of the experiment) and subsequently at 1-minute intervals during 10 minutes of exposure to the ultrasound, and for a further 10 minutes post-exposure, until the end of the experiment at 20 minutes. In general, there were five main parameters for all the studies: the movement speed of the transducer, the size of the treatment, and the frequency, intensity and duration of exposure and post-exposure to ultrasound. These five parameters represented the independent variables for all the studies. The dependent variable throughout was change in tissue temperature (measured in °C) at the skin surface, and at 1, 2, 3, 4 and 5 cm below the skin surface. Data were analysed using the SPSS for Windows software, Version 10.0 (SPSS Inc., 444N Michigan Avenue, Chicago, Illinois 60611, USA). Analyses of the data, using a repeated measures analysis of variance procedure, were performed on change in temperature, rather than actual temperature measured at selected time points. Only data from the 5th, 10th, 15th, and 20th minutes were analysed. This corresponded to the middle and end of the ultrasound exposure phase (5th and 10th minute) and post-exposure phase (15th and 20th minute), as these were considered to be representative of both these phases of data collection. / Data for all 20-minute sampling is provided in the table of means for each experiment. The level of statistical significance was set at 0.05. Results of the reliability study showed that both the infrared spot thermometer and the video thermography unit were reliable within acceptable limits (as defined in this study). The latter, however, was more reliable than the former. In addition, the reliability was better for the post-exposure phase compared with the exposure phase, and for deeper tissues compared with the superficial and surface tissues. An unplanned analysis of the twenty minutes of data (at one minute intervals) suggested the possibility of reducing the duration factor from 20 to 4 (5th, 10th, 15th and 20th minute). In this manner, the data analyses for subsequent studies could be simplified considerably without affecting the overall results. Results of the other protocol-related studies showed that: a. There was no difference in change in temperatures between the slow (60 beats/min or 7cm/s), moderate (120 beats/min or 14cm/s) and fast (180 beats/min or 21cm/s) movement speeds of the transducer. However, for practical reasons, the moderate speed was recommended for subsequent studies; b. There was a significant difference in change in temperatures between the small (2X ERA), medium (3X ERA) and large (4X ERA) treatment sizes. The small treatment size provided the most effective and deeper heating, and was the recommended treatment size for subsequent studies; c. For both 1 and 3 MHz, tissue damage did not occur for intensities up to 1.5 Watts/cm[superscript]2. However, irreversible thermal injury to the tissues occurred at 2.0 Watts/cm[superscript]2 (1 MHz). / Therefore, the recommended maximum intensity at which investigations could be carried out without any risks of thermal injury to the tissues was 1.5 Watt s/cm[superscript]2 for both 1 and 3 MHz. The results from the main study demonstrated that the increase in temperature due to absorption of the ultrasonic energy at any of the investigated target sites (up to 5 cm below surface) was related to the ultrasound frequency, intensity and duration of exposure. For the frequency factor, the evidence seems to suggest that compared with the 3 MHz ultrasound, the 1 MHz frequency may be more appropriate for clinical applications as it does not overheat surface tissues, and at the same time, is able to increase the temperatures of target tissues up to a depth of 5 cm. For the intensity factor, the results suggest that the therapeutic range of intensities which can be considered neither too low (as to be ineffective) nor too high (as to be damaging) are 0.5 to 1.3 Watts/cm 2 and 0.3 to 0.5 Watts/cm[superscript]2 for 1 and 3 MHz respectively The narrow therapeutic range for 3 MHz could render it questionable for clinical applications. In contrast, the larger therapeutic range available for the 1 MHz frequency suggests that it is more suitable for clinical applications and research. For the duration factor, the results demonstrated that the temperatures at all tissue sites increased as the duration of exposure increased. / However, for the post-exposure phase, while the superficial tissues decreased with time, the deeper tissues continued to increase in their temperatures, albeit gradually. In summary, the results demonstrated that a higher frequency, a higher intensity, a greater exposure time and a more superficial site all contribute to a greater change in mean temperature. From these results, a preliminary model to guide clinicians and researchers in determining treatment dosages, based on expected increase in tissue temperatures at the target site, was proposed. While the preliminary model provided is only a first step effort, it is hoped that it can be refined further through use by physical therapists and other users of therapeutic ultrasound.