Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references. Also available in electronic version.

Thesis (Ph. D.)--Brigham Young University. Dept. of Physiology and Developmental Biology, 2006. / Includes bibliographical references (p. 108-115).

Th.--Physiol. animale--Toulouse--I.N.P., 1985. N°: 25.

Th.--Méd.--Saint-Étienne, 1980. N°: 09.

[pt] O presente trabalho trata da caracterização da vazão mássica do refrigerante R404a através de orifícios calibrados de diferentes diâmetros, em função das condições de operação. Um aparato experimental, que representa os fenômenos que ocorrem em um sistema de refrigeração real, foi utilizado para o controle das condições de operação. Os dados experimentais apresentados neste trabalho cobrem a faixa de pressão a montante de 1549 kPa (210 psig) 1618 kPa (220 psig) e 1756 kPa (240 psig) e pressão a jusante de 818 kPa (104 psig) a 1377 kPa (185 psig), tendo o grau de sub- resfriamento se situado entre 1,3 ºC e 18,02 ºC. A revisão bibliográfica realizada mostrou que até a presente data não há, na literatura aberta, dados experimentais para este refrigerante, um dos prováveis substitutos dos CFC s e HCFC s. Os resultados obtidos constituem um fato original para o escoamento do refrigerante R404a através de orifícios calibrados, representando uma importante contribuição tecnológica. É apresentada ainda, uma correlação para dados experimentais obtidos, podendo ser utilizada em futuras simulações de orifícios calibrados. / [en] The present work describes the experimental analysis of flow of refrigerant R404a through short tube orifices, for different diameters and operating conditions. An experimental apparatus was constructed to provide the desired operating conditions. The experimental data covers upstream pressures from 210 psig to 240 psig, downstream pressures from 104 psig to 185 psig and inlet subcooling from 1,30 o C to 18,02 o C. A literature review revealed, at the time of publication, the absence of works on the flow of R404a through short tube orifices. A correlation of the experimental data, to be used in future simulations of short tube orifices, is presented. The results constitute an original contribution to the study of flow of R404a through short tube orifices. / [es] Este trabajo aborda la caracterización de la salida másica del refrigenerante R404a a través de orificios calibrados de diferentes diámetros, en función de las condiciones de operación. Un aparato experimental, que representa los fenómenos que ocurren en un sistema de refrigeneración real, fue utilizado para el control de las condiciones de operación. Los datos experimentales presentados en este trabajo cubren una banda de presión de 1549 kPa (210 psig) 1618 kPa (220 psig) y 1756 kPa (240 psig) y presión aguas abajo de 818 kPa (104 psig) a 1377 kPa (185 psig), con grado de subrefriamiento situado entre 1,3 ºC y 18,02 ºC. La revisión bibliográfica realizada mostró que hasta la presente fecha no hay, en la literatura abierta, datos experimentales para este refrigerante, uno de los probables substitutos de los CFC s y HCFC s. Los resultados obtenidos constituyen un hecho original para el flujo del refrigenerante R404a a través de orificios calibrados, representando una importante contribución tecnológica. Se presentada la correlación para datos experimentales obtenidos, pudiendo ser utilizada en futuras simulaciones de orificios calibrados.

Climate change is becoming more severe than ever in human history and the emission of green house gas urgently needs to be reduced while global energy consumption remains booming. Large-scale application of clean fossil fuel combustion shall be considered as a priority for its economical advantages as well as reliability in meeting global energy needs. Oxygen-fired pressurized fluidized bed combustor technology with downstream carbon capture and sequestration is considered a key approach to clean coal combustion. In such technology, the fluidized bed combustor operates at elevated pressures and houses an in-bed heat exchanger tube bundle. It is essential to understand the rate of heat transfer between the immersed heat exchange surface and the fluidized bed as it is a key parameter in heat exchanger design. The goal of this work was to investigate the impact of pressure and presence of fine particles (i.e., surrogate for pulverized fuel) on the overall tube-to-bed heat transfer coefficient. Experiments were conducted in a pilot-scale fluidized bed with an inner diameter of 0.15 m under cold flow conditions. A tube bundle consisting of five horizontal staggered rows was completely submerged in the bed. One of the tubes was replaced by a heating cartridge housed in a hollowed copper rod. Five thermocouples distributed at 45º intervals along the copper rod circumference measured the surface temperature and ensured that local effects were included. The bed material was large glass beads of 1.0 mm in diameter while the fines were glass beads of 60 µm in diameter and thus susceptible to entrainment. The fine particles were continuously fed to the fluidized bed and then captured downstream by a filter system. Fluidization was conducted at 101, 600 and 1200 kPa with excess gas velocities (Ug - Umf) of 0.21, 0.29 and 0.51 m/s. Fine particle feed rates were 0, 9.5 and 14.4 kg/h. Two heating rod positions (2nd row and 4th row) were studies. Overall, the heat transfer coefficient approximately doubled when pressure was increased from 101 to 1200 kPa. At atmospheric conditions, where the slug flow regime occurred, the maximum heat transfer coefficient was at the bottom of the rod, while it moved to the side of the rod at high pressures where the bubbling regime occurred. As the heating rod moving from 2nd row to the 4th row, the averaged heat transfer coefficient increased by respectively 18%, 9% and 6% at 101, 600 and 1200 kPa. The addition of fine particles decreased the average heat transfer coefficient by 10 to 20 W/m2 K where the time – averaged heat transfer coefficient was approximately 220 and 450 W/m2K at 101 kPa and 1200 kPa respectively. There was no effect on the angular profile across the tube surface. The results showed that average heat transfer coefficients matched the correlation developed by Molerus et al. (1995) within a 5% difference across all conditions when fines were not present.

The transcription factor DEAF-1 is the mammalian homologue of a critical Drosophila developmental gene and is essential for neonatal survival in mice. Haploinsufficiency of Deaf-1 in the testis of adult mice was initially thought to cause loss of spermatogenesis and disrupted morphology of the seminiferous tubules, and this heterozygosity was thought to be sufficient to disrupt epigenetic programming in the developing sperm to produce inheritance of testicular defects in both heterozygous and genotypically normal offspring. Although Deaf-1 knockout mice do display disrupted testis structure, infertility at advanced age, hyperproliferation of early germ cells, and abnormal staging of seminiferous tubules, this phenotype was also observed in normal mouse strains that were born in the SIUC vivarium. Mice ordered from a vendor and raised at SIUC did not show testicular defects. This suggests an environmental factor at the SIUC vivarium may act as an endocrine disruptor during embryonic testicular development. Deaf-1-/- mice die soon after birth, often as the result of exencephaly, a gross neural tube defect (NTD). Unlike many mouse models, exencephalic Deaf-1-/- mice do not display a higher incidence of NTDs in females as compared to their male littermates. DEAF-1 promotes Bax-mediated apoptosis; studies using terminal UTP nick-end labeling (TUNEL) suggest a global increase in apoptosis in both exencephalic and normal Deaf-1-/- fetuses during neurulation as compared to their Deaf-1+/+ littermates. This indicates that Deaf-1 is crucial for correct apoptotic patterning during development, which, in turn, is essential for neural tube closure. Finally, cDNA microarray comparison of e14.5 Deaf-1 knockout and wildtype fetuses reveals expression of translation initiation factor 4g3 (Eif4g3) to be downregulated in Deaf-1-/- fetuses. Electrophoretic mobility shift assay using recombinant DEAF-1, and chromatin immunoprecipitation assay of a human cell line confirmed DEAF-1 could bind the eIF4G3 promoter both in vitro and in vivo. Additionally, transcription of the Deaf-1 Antisense Transcript (Das) was found to be significantly downregulated in both e14.5 fetuses and e18.5 fetal brains from Deaf-1-/- mice, suggesting that either lack of Deaf-1 protein or lack of exons 2 through 5 in Deaf-1 knockout mice causes changes in levels of the noncoding RNA that shares Deaf-1's promoter in the mouse.

Aim of this thesis is to construct a demonstration model of a vacuum tube amplifier with a possibility of measurement of signal on more places and a possibility to see the wiring and construction of the amplifier. The first part of the work treats some important themes concerning vacuum tubes and wiring with them, for example a principle of signal intensification by vacuum tubes, categories of low-frequency amplifiers and description of several types of undesirable distortions. Next part deals with the design of the constructed amplifier, the description of the construction itself and placement of the components on the printed circuit boards and used vacuum tubes and transformers. The following part is focused on measurement of the basic properties of the amplifier and vacuum tubes by means of TESLA BM215A appliance. The final part contains technical parameters of the amplifier and photo documentation.

Made available in DSpace on 2014-12-02T11:16:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-10-16Bitstream added on 2014-12-02T11:21:14Z : No. of bitstreams: 1 000609546.pdf: 1464260 bytes, checksum: 34305688869576b88d9034d68dc81109 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As técnicas biomagnéticas vêm sendo empregadas com sucesso no estudo do trato gastrintestinal (TGI). Elas podem medir o campo magnético originado pela atividade elétrica dos órgãos, o campo de marcadores magnetizados ou a resposta de marcadores ou traçadores a um campo magnético de excitação. Este trabalho apresenta uma coletânea de instrumentações desenvolvidas para aplicações no trato gastrintestinal. Os equipamentos desenvolvidos utilizaram sensor anisotrópico magnetorresistivo (AMR) para medir campo magnético e conversores de tensão true rms-to-dc objetivando a redução de custo das técnicas que empregam excitação magnética alternada (AC). Foram desenvolvidos um método de localização magnética de sonda nasoenteral, uma solução para substituição dos amplificadores lock-in’s por conversores true rms, uma instrumentação com sensor AMR com um eixo de detecção para avaliar o trânsito faringiano, uma instrumentação com sensor AMR com três eixos de detecção para avaliar o trânsito esofagiano e uma instrumentação com 36 sensores que foi aplicada para obter imagens magnéticas de diferentes fantomas e para avaliar a atividade de contração gástrica em um modelo in vivo – ratos. As instrumentações foram avaliadas em testes in vitro e in vivo e apresentaram sensibilidade para o emprego no trato gastrintestinal. Os equipamentos desenvolvidos são de baixo custo, livre de radiação ionizante, portáteis e que possibilitam aplicações em gastroenterologia, farmacologia, farmacotécnica e na clínica médica. / Biomagnetic techniques have been employed successfully to study gastrointestinal (GI) tract. They are enable to measure the magnetic field of magnetized markers, the markers and tracers responses to applied magnetic field excitation, and the magnetic field occurred by GI electrical activity. This work presents some instrumentation developed to evaluate different parameters of GI tract. The equipment built uses anisotropic magnetoresistive (AMR) sensor to measure magnetic field and true rms-to-dc voltage converter in order to reduce the cost of techniques that employ alternate (AC) magnetic excitation. In this work were developed: a magnetic method for localization of enteral feeding tube, a solution to replace lock-in amplifier for true rms converter, an instrumentation using AMR sensor (one axis-sensing) to evaluate the pharyngeal transit time, another instrumentation using AMR sensor (three axis-sensing) to evaluate esophageal transit time and finally, a equipment consisted of 36 AMR sensors to evaluate the gastric motor activity from rats and in order to obtain magnetic images from different kinds of phantoms. All equipments were tested and showed sensitivity to be employed in GI studies. The equipments developed are low cost, radiation free, portable and enable to applications in gastroenterology, pharmacology, pharmaceutical and medical clinic.

Postoperativ halssmärta (POST) är en mycket vanlig komplikation hos patienter som genomgått generell anestesi med intubation.  POST anses av anestesipersonal vara en relativt lindrig komplikation. Patienter upplever det dock som ett stort problem och därför bör det undvikas. Syftet med denna litteraturstudie var att undersöka vad anestesisjuksköterskor kan göra för att förebygga POST som komplikation hos patienter som genomgått generell anestesi med intubation. Examensarbetet är en integrativ litteraturstudie som innefattar tolv globala studier. Litteraturstudiens resultat visar att det finns flera farmakologiska och icke farmakologiska metoder som kan förebygga POST. Lokal behandling med kortikosteroider och NSAID-preparat har förebyggande effekt på POST. Icke farmakologiska interventioner som konformad kuff, substanser som lakritslösning, magnesium och zink lindrar. Vissa studier finner att kortikosteroider och lidokain kan öka förekomsten av POST. I nuläget kan resultatet inte tillämpas av anestesisjuksköterskor då resultaten är tvetydiga och inte kan utföras utan ordination av anestesiolog. Vidare forskning inom området med inriktning på omvårdnad är av yttersta vikt.