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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.
111

THE FALL OF THE TENOR WITH THE RISE OF THE LARYNX

Turay, Gregory 01 January 2017 (has links)
The range and use of the tenor voice in classical music has long been established since the late 19th century. It is widely accepted among pedagogues that the range is C3-C5 (with obvious exceptions depending on the fach). However, with the advent and development of the American Musical as a genre since the early 20th century, the ‘tenor’ has taken on an entirely new direction and range altogether. Several well-known sources have stated that the ‘Broadway tenor’ has a range of A2-A4. This is (as it widely accepted in the classical profession) the range of a baritone. The catalyst of these changes include vaudeville, composers, social trends, and probably most important, the invention and proliferation of the microphone. This study will analyze a cross section of repertoire in order to demonstrate this downward shift of vocal range, and demonstrate some of the main reasons why this shift occurred.
112

Behaviour of axially restrained steel beams with web openings at elevated temperatures

Najafi, Mohsen January 2014 (has links)
Steel beams with web openings are frequently used in construction to achieve attractive, flexible and optimised design solutions. These beams are used to provide passages for building services, to reduce the overall construction height and to achieve long spans. However, the presence of the openings may lead to a substantial reduction in the load carrying capacity of the beam at both ambient and elevated temperatures and introduce additional failure modes including shear-moment interaction at the location of the openings causing the Vierendeel mechanism. Steel beams in practical construction are axially restrained and the presence of this axial restraint can drastically change the behaviour of the beams in comparison to those without axial restraint. One particular issue is premature buckling of the compressive tee-sections around the openings. The aim of this research is to investigate the effects of openings on axially restrained steel beams at elevated temperatures so as to develop an analytical method for design consideration. The analytical derivation will be based on the results of extensive numerical simulations. The research starts with the behaviour of steel beams with web openings under combined axial compression, bending moment and shear force at ambient temperature. The results show that buckling of the compressive tee-sections at the openings can reduce the plastic moment capacity of the openings; and an analytical method has been proposed to incorporate the influences of axial compression and tee-section buckling into the existing shear-moment design equations. The elevated temperature simulations show that axially restrained steel beams with web openings may enter catenary action at much lower temperatures than the commonly accepted critical failure temperatures calculated assuming no axial restraint and no tee-section buckling. Therefore, at the commonly accepted critical failure temperatures, many perforated steel beams exert tensile forces on the adjacent connections. It is important that the connections have the strength and deformation (rotation) capacity to enable catenary action to develop. The parametric study examines, in detail, how changing the different design parameters may affect the elevated temperature behaviour of perforated beams. The examined parameters including load ratio, level of axial restraint, cross-section temperature distribution profile, opening shape, opening size and opening position. Based on the results of the numerical parametric study, an analytical method has been derived to obtain the complete axial force-temperature relationship for axially restrained perforated steel beams. The key points of the analytical method include initial stiffness, point of initial failure under combined axial compression, bending moment and shear force, transition temperature at which the axial force on the beam changes from compression to tension and the magnitude of the tensile force resulting from the beams going into catenary action. Using the analytical method, it is possible to assess the maximum tensile force in the beam and the corresponding temperature so that the safety of the connections can be checked.
113

Efeitos do clonazepam sobre as respostas defensivas medidas em ratos submetidos ao labirinto em T elevado / Effect of clonazepam on the defensive responses measured in rats tested in the elevated T maze.

Marcel Adriano Lopes 29 June 2010 (has links)
Lopes, Marcel Adriano. Efeitos do clonazepam sobre as respostas defensivas medidas em ratos submetidos ao labirinto em T elevado. 2010. 83f. Dissertação (mestrado) - Faculdade de Medicina de Ribeirão Preto - Universidade de São Paulo - Ribeirão Preto, 2010. O labirinto em T elevado (LTE) é um modelo etológico, que evoca comportamentos defensivos correlacionados com o transtorno de ansiedade generalizada (esquiva inibitória) e o transtorno do pânico (fuga). Apesar da validação farmacológica da tarefa de esquiva inibitória deste modelo estar bem estabelecida, algumas questões em relação à tarefa de fuga não estão claras. Resultados prévios da literatura mostram que drogas clinicamente eficazes no tratamento do transtorno do pânico, como antidepressivos tricíclicos (ex: imipramina e clomipramina) e inibidores seletivos da recaptação de serotonina (ex: fluoxetina e escitalopram), aumentam a latência de fuga no LTE, sugerindo efeito do tipo panicolítico. Entretanto, em relação aos benzodiazepínicos de alta potência, também amplamente utilizados na clínica para o tratamento do transtorno do pânico, os dados em relação ao LTE permanecem desconhecidos. Sendo assim, o presente trabalho teve como objetivo investigar o efeito da administração aguda ou repetida (7 ou 14 dias) de clonazepam em ratos submetidos ao LTE. Dada a importância da substância cinzenta periaquedutal dorsal (SCPD) na gênese do transtorno do pânico, verificamos se o efeito da administração aguda de clonazepam no LTE era bloqueado pela administração prévia intra-SCPD do antagonista de receptores BZD flumazenil. Nossos resultados mostram que o tratamento agudo com clonazepam diminuiu as latências de esquiva inibitória e aumentou as latências de fuga do braço aberto, indicativo de efeito ansiolítico e panicolítico, respectivamente. Já a administração repetida deste mesmo benzodiazepínico, seja por 7 ou 14 dias, diminuiu as latências de esquiva inibitória, sem alterar as respostas de fuga. A administração intra-SCPD do antagonista de receptores benzodiazepínicos flumazenil não bloqueou o efeito da administração aguda de clonazepam sobre as respostas defensivas medidas no LTE. Os resultados do presente estudo mostram ainda que o efeito do clonazepam sobre a resposta de fuga é dependente da maneira pela qual a aquisição da resposta de esquiva inibitória é realizada, ou seja, o tratamento agudo com clonazepam foi capaz de alterar esta resposta somente quando a esquiva inibitória foi realizada com 6 tentativas. Em suma, nossos dados mostram que a administração aguda de clonazepam promove efeito panicolítico e ansiolítico no LTE. No entanto, deve ser ressaltado que o efeito panicolítico do clonazepam foi apenas observado após a introdução de uma mudança metodológica no teste do LTE. De uma maneira geral, os resultados obtidos sustentam a associação entre o comportamento de fuga e ataques de pânico. / Lopes, Marcel Adriano. Effect of clonazepam on the defensive responses measured in rats tested in the elevated T maze. 2010. 83f. Dissertação (mestrado) - Faculdade de Medicina de Ribeirão Preto - Universidade de São Paulo - Ribeirão Preto, 2010. The elevated T maze (ETM) is an ethological model that generates in rats defensive behaviors in rats which have been associated with generalized anxiety (inhibitory avoidance) and panic (escape) disorders. A wealth of evidence in the literature supports the validity of the ETM inhibitory avoidance task for detecting the effects of generalized anxiety-effective drugs. However, the effect of panic-effective drugs on escape performance has not been fully investigated yet. Previous studies showed that panic-ameliorating drugs such as tricyclic antidepressants (e.g. imipramine and clomipramine) and selective serotonin reuptake inhibitors (e.g. fluoxetine and escitalopram), increase escape latencies in the ETM, suggesting a panicolytic-like effect. The effect of high-potency benzodiazepines agonists such as clonazepam and alprazolam, also widely used for the treatment of panic disorder, remains unknown. In this study we investigated the effect of acute or repeated administration (7 or 14 days) of clonazepam in rats submitted to the ETM. Given the attributed importance of the dorsal periaqueductal gray matter (dPAG) in the genesis/regulation of panic disorder, we also investigated whether the effects caused by the acute administration of clonazepam in ETM can be blocked by prior intra-dPAG administration of the BZD receptor antagonist flumazenil. Our results showed that acute treatment with clonazepam impaired inhibitory avoidance acquisition and increased escape latencies, suggesting anxiolytic and panicolytic effects, respectively. Repeated administration of clonazepam, either for 7 or 14 days, also impaired inhibitory avoidance acquisition, but did affect escape expression. Intra-dPAG injection of flumazenil did not block the effect of clonazepam on the defensive responses measured in ETM. Our results also showed that the effect of clonazepam on the escape response is dependent on the way inhibitory avoidance acquisition is measured, i.e. the drug anti-escape effect was only observed in group of animals that had 6 but not 3 trials to acquire inhibitory avoidance. Altogether, our data show that clonazepam causes both anxiolytic and panicolytic effects on ETM, in accordance to its therapeutic profile. However, it should be emphasized that the panicolytic effect of clonazepam was only observed after the introduction of a methodological modification in the ETM test protocol. Overall, our findings support the proposed association between escape behavior and panic attacks.
114

Efeitos de uma atmosfera enriquecida com CO2 sobre a fotossíntese, o crescimento e o metabolismo de carboidratos do açaí (Euterpe oleracea Mart.) / Effects of a CO2-enriched atmosphere on the photosynthesis, growth, and carbohydrate metabolism of açaí (Euterpe oleracea Mart.)

Leila Cristina Mortari 26 November 2012 (has links)
Dentre a gama de estudos existentes acerca das respostas de plantas ao incremento de CO2 atmosférico associado às mudanças climáticas, são poucas as investigações que contemplam espécies amazônicas frente à relevância desse ecossistema, e se desconhecem estudos desse aspecto com palmeiras. O açaí (Euterpe oleracea Mart., Arecaceae) é uma espécie típica de planícies da Floresta Amazônica sujeitas ao regime anual de inundação e, além de ser extremamente tolerante à anóxia, apresenta elevado valor comercial e um potencial para a produção de energia a partir de biomassa, gerando uma exploração economicamente sustentável. Este trabalho buscou caracterizar o crescimento inicial de plântulas de açaí quanto à fotossíntese, crescimento e metabolismo de carboidratos e investigar as respostas desses parâmetros ao incremento de CO2 atmosférico (de 380ppm - ambiente para 760ppm - elevado) em duas escalas temporais: ao longo do desenvolvimento das plântulas (entre 105 e 195 dias após a germinação, período de desenvolvimento da segunda folha) e ao longo de 24 horas (aos 175 dias após a germinação). Foram analisadas medidas de altura, área foliar, acúmulo e alocação de biomassa, curvas de resposta da fotossíntese à luz, conteúdo de clorofila e concentração de carboidratos não-estruturais. Foi verificado que o período de estabelecimento das plântulas se estende até cerca de 150 dias após a germinação e se sobrepôs ao experimento com elevado CO2. A presença de outra via de entrada de carbono além da fotossíntese tamponou mas não inibiu os efeitos do aumento de CO2 atmosférico. Foram observadas ao longo do experimento reduções na área foliar, condutância estomática e respiração no escuro e aumentos na fotossíntese e eficiência de uso da água, além de aumento na concentração de carboidratos não-estruturais e na biomassa. Os dados obtidos após o esgotamento das reservas do endosperma não apresentaram sinais de que a planta aclimatará ao incremento de CO2, pois aos 90 dias de experimento foram observadas as maiores porcentagens de aumento na fotossíntese, 89%, e no teor de amido, 300%. Esses resultados indicam que essa espécie apresenta uma grande capacidade de aumento da força de dreno, o que diminui a sinalização por açúcares possibilitando a manutenção de uma resposta positiva ao incremento de CO2 atmosférico / Despite all knowledge available nowadays on plant responses to increasing atmospheric CO2, few are the studies that focus on Amazonian species in contrast to the biological relevance of this ecosystem, and no record has been found of Palm species analysis on this area of research. Açaí palm (Euterpe oleracea Mart., Arecaceae) is a typical species of Amazon plains subjected to annual periods of flooding. Apart from being extremely anoxia tolerant, this species presents high commercial value and a potential of energy production through biomass utilization, counting towards a sustainable economic exploitation. This study aimed to characterize the initial growth of açaí palm seedlings as for photosynthesis, growth and carbohydrate metabolism and to investigate these parameters\' responses to an increase on atmospheric CO2 (from 380ppm - ambient to 760ppm - elevated) on two temporal scales: throughout seedling development (from 105 to 195 days post germination, time span of second leaf development) and throughout 24 hours (at 175 days post germination). Analysis included: height, leaf area, biomass increase and allocation, light-response curves, chlorophyll content and non-structural carbohydrate concentration. It was observed that the seedling establishment period extends to 150 days post germination and overlapped the elevated CO2 experiment. The presence of another carbon entry pathway besides photosynthesis buffered the effects of elevated CO2, but did not inhibit them. Results observed were reductions on leaf area, stomatal conductance and dark respiration and increases on photosynthesis, water use efficiency, non-structural carbohydrate content and biomass. The results obtained after seed reserves were depleted did not seem to indicate that this species will present acclimation to elevated CO2, since the greater percentages of increase on photosynthesis (89%) and starch content (300%) occurred at the end of the experiment (90 days on elevated CO2). These results indicate that açaí palm seedlings have a large capacity of sink strenght increase, which reduces sugar signaling and maintains a positive response to the increase on atmospheric CO2
115

Změny v obsahu gliadinových frakcí bílkovin u dvou genotypů ozimé pšenice s rozdílnou délkou vegetační doby v reakci na zvýšenou koncentraci oxidu uhličitého. / Changes in the content of gliadin protein fractions in two genotypes of winter wheat with different lengths of vegetation time in response to an elevated concentration of carbon dioxide.

Janíčková, Vlasta January 2019 (has links)
This diploma thesis deals with an influence of elevated concentration of carbon dioxide (700 mol·mol-1) on the protein content of gliadin fraction in winter wheat (Triticum aestivum) early var. Avenue and late var. Tobac. To separate gliadin, the A-PAGE method was used, proteins were quantified by computer densitometry. Signitificant influence of genotype on the gliadin fraction of the gluten proteins was found. Due to the increased concentration of CO2, the content of the gliadin fraction of the Avenue variety was reduced, while the content of the gliadin fraction of the Tobac variety increased. Effect of elevated CO2 concentration was at var. Avenue showed a significant difference in total content of gliadin fraction and fraction 1,2-gliadins. A significant difference was found in the var. Tobac only in the fraction 1,2-gliadin.
116

Vliv zvýšené koncentrace oxidu uhličitého na kvalitu pšeničné mouky / Influence of carbon dioxide elevated concentration on wheat flour quality

Drahovzalová, Kateřina January 2010 (has links)
This thesis studied the influence of elevated carbon dioxide concentration on the properties of ears, grain and flour in two varieties of wheat (Triticum aestivum). The Vánek and Septima varieties were grown in special greenhouses, both in normal atmosphere with carbon dioxide concentration (AC = 385 ?mol?mol-1), and at elevated carbon dioxide concentration (EC = 700 ?mol?mol-1). Quantitative analysis of grain (the content of crude protein, starch, moisture and hardness of grain) was carried out using NIR, gluten content (gluten index) was determined after washing with water and gluten quality was expressed as falling number. Total crude protein content was determined according to Kjeldahl, total amino acids and amino acids content by ion exchange chromatography. Variety Vánek showed significantly larger size of the spikes, more grains and higher grain weight, when it was cultivated in the atmosphere of elevated CO2 concentration. For variety Septima, the size of AC and EC ear variants was comparable, but the ears of corn grown in the EC had a significantly greater number of grains and greater weight. Vánek variety grown in elevated CO2 concentration had lower weight of 100 grains, Septima variety grown in elevated CO2 concentration had greater weight of 100 grains. The varieties Vánek and Septima grown at elevated CO2 concentration showed significantly lower content of crude protein (28.4%) and gluten index (by 34.6%). In comparison with the AC variant, EC also showed lower overall content of crude protein and amino acids.
117

Vliv zvýšené koncentrace oxidu uhličitého a dusíkatého hnojení na obsah proteinů gluteninové a gliadinové frakce u ozimé pšenice / Impact of elevated carbon dioxide concentration and nitrogen nutrition on protein content of glutenin and gliadin fraction in winter wheat

Chadimová, Klára January 2016 (has links)
The present study investigates effects of elevated atmospheric carbon dioxide concentration, different nitrogen fertilization levels, drought and UV radiation on protein content of wheat gluten fractions glutenins and gliadins. Winter wheat cultivar Bohemia was grown under ambient CO2 concentration (AC; 400 mol CO2.mol-1) and elevated CO2 concentration (EC; 700 mol CO2.mol-1). Half of the samples was fertilized with 200 kg N.ha-1 (N+) and the other part stayed unfertilized (N–). Other environmental factors were UV radiation exclusion (UV–, UV+) and drought (DRY, WET). Gliadins were separated by A-PAGE, glutenins by SDS-PAGE. Proteins were quantified by computer densitometry. Nitrogen fertilization caused an significat increase of gliadins and glutenins. While some gliadins subfractions were significantly lowered by drought, HMW glutenin subunits showed significant increase. UV radiation exclusion resulted in significant decrease of some gliadin subfractions and glutenin subunits. CO2 enrichment caused significant increase of glutenin subfractions HMW 1 and 2, while gliadin subfractions -5 1 and 1 were significantly decreased by elevated CO2 concentration.
118

Elevated Temperature Effects on Local Buckling of Wide Flange Columns

Baidar, Nikki 24 May 2022 (has links)
No description available.
119

Investigation of Tensile Strength of Carbon Fabric-Reinforced Cementitious Matrix (FRCM) at High Temperatures

Asgharigharakheili, Hamidreza 29 April 2022 (has links)
Maintenance and rehabilitation of existing masonry and reinforced concrete structures are of great importance in the field of civil engineering. Due to deterioration and severe environment, numerous structures fail to meet functional or safety requirements, and as a result, they should be strengthened. Several methods have been utilized to repair the structures, including steel plate bonding, cable post-tensioning, and section enlargement. However, these methods bring disadvantages, such as significant added dead load and high labour cost. Therefore, externally bonding with composite materials has attracted considerable attention recently. Externally bonded fibre-reinforced polymer (FRP) sheets have been widely used to strengthen reinforced concrete and masonry structures. FRP has been a common method to provide a higher service life for structures for several decades. However, strengthening structural members with FRP introduces certain drawbacks, such as their poor performance in fire scenarios caused by the rapid softening of the polymer-based resin. An alternative strengthening system known as a fabric-reinforced cementitious matrix (FRCM) has been developed to address this issue by replacing resin-based material with an inorganic cementitious-based matrix. Nonetheless, the performance of FRCM at high temperatures has not been investigated sufficiently so far. Hence, this research focused on the mechanical behaviour of FRCM at high temperatures. This experimental research investigates the tensile performance of carbon FRCM at high temperatures. First, the temperature distribution within the specimens during heating was studied using nine specimens with one, two, or three layers to reveal the required time for the inner fabric to reach a steady temperature. Then, the tension and stiffness degradation of FRCM coupons were studied at different temperatures. A total of 84 FRCM coupons were fabricated and tested in tension; 60 of the tests were conducted at steady-state conditions in which temperature was held constant and load increased, and 24 specimens were carried out in transient-state tests, in which load was constant, and temperature grew. In order to provide a more comprehensive knowledge concerning the FRCM composite, some key variables were included in this research. These parameters are the number of layers (1, 2, 3) leading to different thicknesses (20, 30, 40 mm), the orientation of the fabric layer (unidirectional and bidirectional), target temperature (ambient, 100, 200, 300, 400°C), and heating condition (steady-state, transient state). These tests aimed to reveal the primary mechanical characteristics such as ultimate strength and cracked elastic modulus at different temperatures and compare them with control specimens tested at room temperature. With the increase in the number of fabric grids from one to two and three, the stress at failure decreased by about 11 and 18%, respectively. With regards to cracked elastic modulus two and three-layered specimens showed 18 and 20% reduction in value. It is also noteworthy to mention that overall load capacity of specimens rose with the increase in number of layers; however, due to the more significant increase in area, the stress was reduced. The same decreases in the cracked elastic modulus and ultimate strength were observed as the target temperature increased. Increasing the temperature to 400°C led to a decrease in ultimate strength and cracked elastic modulus of approximately 60 to 70%. Furthermore, the bidirectional specimens showed a better behaviour than unidirectional specimens in terms of ultimate strength; however, their cracked elastic moduli were almost the same. With regards to the transient-state tests, as the material became thicker, the failure temperature increased considerably. For instance, a 20-mm specimen failed at 467°C with a 20% sustained load, while a 30-mm specimen failed at 558°C. Another vital parameter studied in transient-state tests was the decrease in temperature with the increase in sustained load. An example of this is the 20-mm specimens which failed at 352 and 258°C, while they were preloaded to 40 and 60% of their capacities. The conclusions of this study suggest that FRCM materials do retain a non-negligible strength capacity at high temperatures. However, further investigations to reveal FRCM bond behaviour and retrofitted structural members at high temperatures are still required to provide comprehensive knowledge.
120

Influences of Nitrogen Supply and Elevated CO2 on Nitrogen Consumption, Nitrogen Loss, Tissue Nitrogen Concentration, and Yield of Hydroponic Wheat

Ritchie, Karl B. 01 May 1994 (has links)
Wheat was grown hydroponically for 23 days ( early boot stage) in a controlled environment at NO3- concentrations of 100 and 1000 μ,M and CO2 levels of 360 and 1200 μ,mol mo1-1. Nitrogen consumption and transpiration were measured daily. Tissue nitrogen concentration, total biomass, and percent root mass were measured at harvest. Nitrogen recovery and nitrogen use efficiency were calculated. Elevated CO2 increased nitrogen consumption of the 100 μ,M NO3- treatment by 13.6% and the 1000 μ,M NO3- treatment by 21.3%. These increases were particularly evident during tillering and early grain fill. Whole plant nitrogen, shoot NO3-, and root NO3- concentrations were increased by elevated CO2. High CO2increased biomass by 15% and increased percent root mass by 11 %. Nitrogen recovery and nitrogen use efficiency were similar at both CO2 concentrations. Transpiration (L m-2ground d-1) decreased by 40% in elevated CO2. The 1000 μ,M NO3- treatment consumed more NO3- than did the 100 μ,M NO3- treatment (8.1% in ambient CO2, 15.5% in elevated CO2); this effect was most pronounced during the last 5 days of the experiment (flag leaf emergence and early grain fill). Percent root mass increased as N concentration decreased from 1000 to 100 μ,M. Nitrogen levels did not significantly affect tissue N concentration or biomass. Nitrogen losses increased as N supply increased; an average of 16% of the nitrogen added to the 100 μ,M NO3- treatment was lost, while the 1000 μ,M NO3- treatment lost 21%. Nitrogen use efficiency and transpiration were similar in both nitrogen treatments.

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