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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.
1

The Effects of Environmental Temperature on Locomotor Performance and Growth Patterns in Spotted Salamander, Ambystoma Maculatum

Almeida, Suellen 01 January 2010 (has links) (PDF)
THE EFFECTS OF ENVIRONMENTAL TEMPERATURE ON LOCOMOTOR PERFORMANCE AND GROWTH PATTERNS IN SPOTTED SALAMANDER, AMBYSTOMA MACULATUM SEPTEMBER 2010 SUELLEN ALMEIDA, B.A., UNIVERSITY OF MASSACHUSETTS AMEHRST M.A., UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Duncan J. Irschick Variation in temperature has a profound effect on many aspects of an animal’s physiology, behavior, and performance capacities. Although animals are capable of coping with a range of temperature, they are adapted to specific boundaries of temperature. In an era of global climate change, it is fundamental to comprehend how organisms will react in relation to temperature-related stress and how warmer environmental temperature will affect whole organism performance, as these traits are often crucial to survival. In this study, I examined the effects of temperature on time to hatching period, body length, and larval growth rate. Specifically, I address the following two questions. First, does an increase in temperature affect the duration of time to hatching period? Second, do temperature and the duration of the time to hatching period affect body length at the time of hatching, subsequent growth rate? Furthermore, I investigate the effects of temperature on larval locomotor performance by examining whether or not temperature can result in any impairment of locomotor performance variables (velocity and acceleration). Specifically, I wish to address the following question, does an increase in environmental temperature affect both larval maximum and average velocity and acceleration? In order to answer such questions I raised one egg cluster of Spotted Salamander, Ambystoma maculatum, in two different temperatures (15°C and 21°C). I maintained both the eggs and the resulting larvae in these different temperature regimes until the larvae had reached two weeks of age. I then examined the effects of temperature on body length, growth rate, and locomotor performance. I found that temperature does not have a direct significant effect on body length in A. maculatum. However, I found that temperature has a significant effect on the length of time to hatching period and that the length of time to hatching period is directly correlated to body length. I also found that temperature does not have a significant effect on larval velocity but does have a significant effect on larval acceleration. I argue here that an increase in the mean environmental temperature could result in a decrease in locomotor performance and consequent higher predation susceptibility.
2

The role of genetically defined lamina VII spinal interneurons in generating the locomotor rhythm

Dyck, Jason Unknown Date
No description available.
3

Impact of Ghrelin Receptor Antagonism on Nicotine and Cocaine Drug Reactivity in Rats

Clifford, Patrick Shane 03 October 2013 (has links)
Ghrelin is a 28 amino acid peptide that interacts with ghrelin receptors (GHS-Rs) to modulate brain reinforcement circuits. Systemic ghrelin infusions augment cocaine (COC) stimulated locomotion and conditioned place preference (CPP) in rats, whereas genetic or pharmacological ablation of GHS-Rs has been shown to attenuate the acute locomotor-enhancing effects of nicotine (NIC) and COC, and to blunt the CPP induced by food, alcohol, amphetamine and COC in mice. The stimulant NIC can induce CPP and like COC, repeated administration of NIC induces locomotor sensitization in rats. In experiment 1, we examined the effects of GHS-R antagonism with JMV 2959 on COC-induced locomotion and found that JMV 2959 suppresses COC-induced locomotor sensitization. In experiment 2, we examined the effects of GHS-R antagonism with JMV 2959 on NIC-induced locomotion and found that JMV 2959 suppresses NIC-induced locomotor sensitization. In experiment 3, we examined the effects of GHS-R knockout on COC-induced locomotion and found that animals sustaining GHS-R knockout display a suppression of COC-induced locomotor sensitization. In experiment 4, we examined the effects of GHS-R knockout on COC-induced locomotion and found that animals sustaining GHS-R knockout display a suppression of COC-induced locomotor sensitization. In experiment 5, we examined the effects of JMV 2959 on NIC-enhanced intracranial self-stimulation (ICSS) responding and found that JMV 2959 alone had no effect, but when combined with NIC,JMV 2959 pretreatment reversed the enhancement of responding produced by NIC. In experiment 6, we examined the effects of GHS-R knockout on ICSS responding and found that animals sustaining GHS-R knockout were unable to acquire ICSS at current intensity levels that would support responding by WT animals. It was not until the intensity was ramped up four fold that these knockout rats were able to acquire responding. These results show that antagonism of GHS-Rs diminishes the reinforcing effects of NIC and COC. This provides evidence that antagonists of GHS-Rs could be useful in the treatment of drug addiction, particularly that involving nicotine.
4

Pseudogout and the solubility of calcium pyrophosphate dihydrate crystals : a crystal shedding hypothesis

Bennett, R. M. January 1978 (has links)
No description available.
5

Patología Quirúrgica del Aparato Locomotor Servicio de Ortopedia y Traumatología del Hospital Santa Rosa

Chinchayan Palma, Segundo Rodolfo January 2002 (has links)
El presente trabajo hace un estudio estadístico retrospectivo de la actividad quirúrgica del aparato locomotor efectuado en el servicio de Ortopedia y Traumatología del Hospital Santa Rosa desde noviembre 1990 a octubre de 1992, realizándose 126 intervenciones quirúrgicas en 108 pacientes (100%) El grupo etario más comprometido corresponde a los pacientes menores de 20 años de edad (48.5%) y son del sexo masculino. La etiología más frecuente son los ocasionados por accidente de tránsito. El diagnóstico corresponde a las fracturas y el segmento anatómico más dañado es el muslo 27.8%. Los pacientes en algunos casos presentan lesiones asociadas con otros segmentos anatómicos. El tratamiento de las fracturas se realizó mediante Osteosintesis AO, Enclavijamiento, Enclavamiento, Cerclajes, Fijación Externa, Artroplastia, limpieza quirúrgica, las fracturas consolidaron en el tiempo esperado, las complicaciones 2.8% por falla técnica infecciones 0,7%.
6

Relación entre flexibilidad de los miembros inferiores y compensaciones posturales al sostener la posición de “en dehors” en estudiantes de ballet de la UNMSM– 2013

Muñoz Ynca, Jerson José, Portocarrero Tafur, Robert January 2013 (has links)
Objetivo: Determinar la relación entre la flexibilidad de los miembros inferiores y las compensaciones posturales que se producen al sostener la posición de “en dehors” en los estudiantes de ballet de ballet de la Universidad Nacional Mayor de San Marcos, año 2013. Materiales y métodos: Corresponde a un estudio de tipo correlacional, transversal y prospectivo, de Los Estudiantes de Ballet que Pertenecen a la Escuela de Ballet de La Universidad Nacional Mayor de San Marcos, cuyas edades están comprendidas entre 15 y 20 años. Se evaluó mediante una ficha que comprende el test de Flexitest y una evaluación postural, la muestra estuvo compuesta por 70 estudiantes, cumpliendo los criterios de inclusión 64 de ellos. Resultados: en relación a la flexibilidad de los miembros inferiores y las compensaciones posturales que se producen al sostener la posición de “En Dehors”, se encontró que aquellos Estudiantes de Ballet que presentan un nivel de flexibilidad alta y media, presentaron un bajo nivel de compensaciones, que aquellos que tienen un nivel bajo de flexibilidad, donde predominó el nivel de compensación postural alta. Conclusiones: se demostró que, cuanto mayor es el nivel de flexibilidad en los miembros inferiores de los estudiantes de ballet, menor será el número de compensaciones posturales que se producen al sostener la posición de en dehors. Se puede concluir, entonces, que la flexibilidad de los miembros inferiores influye inversamente en las compensaciones posturales. Palabras clave: posición de “en dehors”, flexibilidad, compensación postural.
7

ANALYSIS OF BEHAVIORAL AND NEURONAL ACTIVATION FOLLOWING AMPA AND NMDA MICROINJECTIONS INTO THE PERIFORNICAL LATERAL HYPOTHALAMIC AREA IN RATS

Li, Frederick Wai-Tsin 28 January 2011 (has links)
Although the perifornical lateral hypothalamic area (PeFLH), which contains orexin/hypocretin (OX) neurons, plays an important role in arousal-related behaviors, its neuromodulatory inputs are incompletely understood. The present study examined the role of glutamatergic inputs to the PeFLH in various arousal-related behaviors. Adult male rats received a microinjection of the ionotropic glutamate receptor agonists AMPA (1 and 2 mM) or NMDA (1 and 10 mM), or vehicle into the PeFLH, and were placed in an open field; 90 min later, rats were perfused for immunohistochemistry for OX and c-Fos as a marker of neuronal activation. AMPA injections dose-dependently increased locomotion, rearing, and drinking. NMDA injections (at 10 mM) increased locomotion and feeding. All these behaviors (except feeding) were positively correlated with the number of c-Fos/OX-immunoreactive neurons. These results support the role of ionotropic glutamate receptors on OX (and other) neurons in the PeFLH in the regulation of locomotor and ingestive behaviors.
8

The structural and functional specialisation of locomotion in the cheetah (Acinonyx Jubatus)

Hudson, Penny Elena January 2011 (has links)
No description available.
9

Lesões músculo-esqueléticas em praticantes de corrida de médias e longas distâncias

Marmeleira, José Francisco Filipe January 2003 (has links)
No description available.
10

Dinâmica do aparelho locomotor em sujeitos amputados e não-amputados do membro inferior

Monteiro, Rita de Cássia Rigotti Vilela [UNESP] 26 May 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:34:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-05-26Bitstream added on 2014-06-13T20:45:41Z : No. of bitstreams: 1 monteiro_rcrv_dr_guara.pdf: 1568003 bytes, checksum: 1added36a6b4036e50ed7b781eb15d26 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / No corpo humano o sistema ósteo-articular dá a sustentação ao corpo humano e sobre ele o sistema muscular e outros tecidos que compõem o aparelho locomotor. Apesar da flexibilidade existente nos músculos, o estudo clássico da biomecânica considera os membros do aparelho locomotor humano como sendo corpos rígidos. Para analisar e estudar tais sistemas, os vários componentes devem ser identificados e suas propriedades físicas determinadas, a fim de se obter as equações que regem o seu movimento. Tal procedimento pode ser feito utilizando-se o modelo multicorpo, para o qual, neste trabalho, foi empregado o método de Kane. Os dados de entrada, como forças no pé durante a marcha, foram coletados por meio de uma plataforma de força, acoplada a uma esteira ergométrica que utilizou extensômetros, e, simultaneamente, com o auxílio de LEDS, foi possível obter dados da filmagem. Para este modelo físico foram utilizados programas, tais como AutoLev, Excel, AutoCad e Fortran. De posse do modelo, foram feitas as análises comparativas dos torques e forças verticais e horizontais no quadril e joelho de amputados e não-amputados, bem como a análise estatística não-paramétrica nos dois grupos, utilizando-se o método de Mann Whitney, com significância de 10≤α%, na qual foi constatado que os torques no quadril dos amputados são estatisticamente diferentes dos torques dos não-amputados; já no joelho esta diferença ocorre em 50% do passo. Não foram encontradas diferenças significativas nas forças entre os dois grupos, exceto em alguns instantes do ciclo da marcha na força cortante. / The osteo-articulate system is what gives the sustenance to the body and to the muscular and other tissue system that compose the locomotor apparel. In spite of the existent flexibility in the muscles, the classic study of the biomechanics considers the members of the human locomotor apparel as being rigid bodies. To analyze and to study such systems, the various components should be identified and their physical properties determined, in order to obtain the equations that govern their movement. Such procedure can be made using the multi-body model, for which, in this work, the method of Kane was used. The entrance data, as forces under the foot during the march, were collected using a platform of force, which is a treadmill with extensometers, and, simultaneously, with the aid of LEDS, it was possible to obtain data of the filming. For this physical model programs were used, such as: AutoLev, Excel, AutoCad and Fortran. By utilizing the model, it was possible to make the comparative analyses of the torques and vertical and horizontal forces in the hip and knee of amputee and no amputee, and also the nonparametric statistical analysis using Mann Whitney's method, with value of 10≤α%, in which was verified that the torques in the hip of those amputees are different to the no amputee; in the knee this difference happens in between 50% of the steps. There were not found significant differences of forces among the two groups, there were exceptions in some moments of the gait cycle at the shear force.

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