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Strenght training and anabolic steroids : a comparative study of the trapezius, a shoulder muscle and the vastus lateralis, a thigh muscle, of strength trained athletesEriksson, Anders January 2006 (has links)
Strength training is widely used to increase performance in sports with high physical demands. The use of drugs such as anabolic steroids among athletes is a wellknown phenomenon, and the effects of these drugs on physical performance documented. The studies presented in this thesis focused on the mechanisms of muscle fiber hypertrophy in the vastus lateralis and the trapezius muscles of strength trained elite athletes. The main hypothesis was that the muscle adaptations to strength training and anabolic steroids are muscle specific. Biopsies were obtained from the trapezius and the vastus lateralis from three groups of elite power lifters. Nine used drugs, ten did not and seven had previously used drugs. Six sedentary males served as controls. The biopsies were frozen and cut in serial cross sections. Histological and immunohistochemical staining techniques were used to analyze muscle fiber morphology and pathology. Fiber type distribution, fiber area, myonuclei number and distribution, satellite cell number and proportion of split fibers were counted and compared for the two muscles within and between the groups. The main findings were that: a) Muscle fiber hypertrophy by strength training is further increased by anabolic steroids. b) The number of nuclei per muscle fiber is higher in power lifters using anabolic steroids compared to non-steroids using lifters. c) Among power lifters who have withdrawn from anabolic steroid usage and training for several years, the number of myonuclei, both subsarcolemmal and internal, remains high. d) In active power lifters, anabolic steroids have no further effect on the number of satellite cells per fiber. e) Power lifters have a high proportion of split fibers. High intensity resistance training increases muscle strength and banned substances such as testosterone and anabolic steroids can enhance the training effects. The studies on muscle cell morphology presented in this thesis reveals that anabolic steroids and testosterone increases muscle fiber size and adds more nuclei to the muscle cell. Based on the morphological appearance of muscle sections from doped and nondoped power lifters, we conclude that testosterone and anabolic steroids enhances the hypertrophic effects of training without adding new features. The addition of myonuclei by training and doping appears to be longer lasting in some muscles than in others. The high proportion of split fibers in power lifter is probably due to high mechanical stress. The findings and conclusions in this thesis raise questions regarding relevant suspension times for athletes caught with banned substances in the body.
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Skeletal muscle health and function in lifelong endurance trained octogenariansHayes, Erik S. 09 June 2011 (has links)
Access to abstract permanently restricted to Ball State community only / Access to thesis permanently restricted to Ball State community only / School of Physical Education, Sport, and Exercise Science
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Developing techniques for evaluating the susceptibility of root-disease resistant Port-Orford-Cedar to foliar and stem canker diseases /Martin, Danielle K. H. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 128-132). Also available on the World Wide Web.
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Respostas ecofisiológicas de Andropogon lateralis Nees subsp. lateralis (capim-caninha) : variação ecotípica ou plasticidade fenotípica? / Ecophysiological responses of andropogon lateralis nees Subsp. Lateralis (caninha grass) : ecotypic variation or Phenotypicplasticity?Porto, Claudia Beltrame January 2004 (has links)
Plasticidade fenotípica é a capacidade de um organismo alterar sua fisiologia e/ou morfologia em decorrência de suas interações com o meio, podendo resultar em uma maior tolerância às modificações ambientais. Tendo em vista que a seleção natural age sobre o fenótipo, a plasticidade fenotípica se caracteriza como um importante mecanismo gerador de variabilidade populacional. Em populações com grande potencial plástico pode ocorrer a formação de ecótipos, gerando populações geneticamente adaptadas às condições do seu local de origem. Este estudo teve como objetivo principal verificar a ocorrência de variações fenotípicas e a formação de ecótipos em duas populações de Andropogon lateralis subsp. lateralis do Rio Grande do Sul, provenientes de duas regiões fisiográficas, Depressão Central e Campos de Cima da Serra. As plantas foram cultivadas em casa de vegetação e avaliadas quanto a seus padrões de respostas fisiológicas, morfológicas e fenológicas a três níveis de adubação nitrogenada e a dois regimes hídricos. As populações apresentaram o mesmo padrão de resposta fotossintética, mas mostraram diferentes respostas quanto a atributos morfológicos, demonstrando diferenças em sua habilidade de responder às influências ambientais. Observou-se também uma assincronia temporal na floração das populações das duas regiões. Os resultados obtidos indicam a formação de ecótipos morfológicos para a espécie e a importância da variabilidade genética nos processos adaptativos e evolutivos nas regiões fisiográficas do Rio Grande do Sul. / Phenotypic plasticity is the capacity of an organism to modify its physiology andJor morphology as the result of interaction with the environment, which may result in an enhanced tolerance to environmental variation. Phenotypic plasticity generates populational variability, since natural selection acts on the phenotype. Ecotypes may appear among populations with significant plastic potential, which will then generate populations genetically adapted to the conditions of their habitats. The main aim of the present study was to verify the occurrence of phenotypic variations and the formation of ecotypes in two populations of Andropogon lateralis subsp. lateralis in Rio Grande do Sul, originating from two physiographic regions - the Depressão Central and Campos de Cima da Serra. The plants were grown in greenhouses and evaluated from the point of view of their physiological, morphological and phenological responses, first at three levels of nitrogen availability and second, under two sets of water availability conditions. The populations presented the same standard of photosynthetic response, but gave different responses regarding morphological attributes, thereby demonstrating differences in their ability to respond to environmental influences. Asynchronism of the flowering period was also noted in the populations from the two regions. The results obtained indicate the formation of morphological ecotypes with regard to the species and underline the importance of phenotypic plasticity in the adaptive and evolutive processes in the physiographic regions of Rio Grande do Sul.
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Respostas ecofisiológicas de Andropogon lateralis Nees subsp. lateralis (capim-caninha) : variação ecotípica ou plasticidade fenotípica? / Ecophysiological responses of andropogon lateralis nees Subsp. Lateralis (caninha grass) : ecotypic variation or Phenotypicplasticity?Porto, Claudia Beltrame January 2004 (has links)
Plasticidade fenotípica é a capacidade de um organismo alterar sua fisiologia e/ou morfologia em decorrência de suas interações com o meio, podendo resultar em uma maior tolerância às modificações ambientais. Tendo em vista que a seleção natural age sobre o fenótipo, a plasticidade fenotípica se caracteriza como um importante mecanismo gerador de variabilidade populacional. Em populações com grande potencial plástico pode ocorrer a formação de ecótipos, gerando populações geneticamente adaptadas às condições do seu local de origem. Este estudo teve como objetivo principal verificar a ocorrência de variações fenotípicas e a formação de ecótipos em duas populações de Andropogon lateralis subsp. lateralis do Rio Grande do Sul, provenientes de duas regiões fisiográficas, Depressão Central e Campos de Cima da Serra. As plantas foram cultivadas em casa de vegetação e avaliadas quanto a seus padrões de respostas fisiológicas, morfológicas e fenológicas a três níveis de adubação nitrogenada e a dois regimes hídricos. As populações apresentaram o mesmo padrão de resposta fotossintética, mas mostraram diferentes respostas quanto a atributos morfológicos, demonstrando diferenças em sua habilidade de responder às influências ambientais. Observou-se também uma assincronia temporal na floração das populações das duas regiões. Os resultados obtidos indicam a formação de ecótipos morfológicos para a espécie e a importância da variabilidade genética nos processos adaptativos e evolutivos nas regiões fisiográficas do Rio Grande do Sul. / Phenotypic plasticity is the capacity of an organism to modify its physiology andJor morphology as the result of interaction with the environment, which may result in an enhanced tolerance to environmental variation. Phenotypic plasticity generates populational variability, since natural selection acts on the phenotype. Ecotypes may appear among populations with significant plastic potential, which will then generate populations genetically adapted to the conditions of their habitats. The main aim of the present study was to verify the occurrence of phenotypic variations and the formation of ecotypes in two populations of Andropogon lateralis subsp. lateralis in Rio Grande do Sul, originating from two physiographic regions - the Depressão Central and Campos de Cima da Serra. The plants were grown in greenhouses and evaluated from the point of view of their physiological, morphological and phenological responses, first at three levels of nitrogen availability and second, under two sets of water availability conditions. The populations presented the same standard of photosynthetic response, but gave different responses regarding morphological attributes, thereby demonstrating differences in their ability to respond to environmental influences. Asynchronism of the flowering period was also noted in the populations from the two regions. The results obtained indicate the formation of morphological ecotypes with regard to the species and underline the importance of phenotypic plasticity in the adaptive and evolutive processes in the physiographic regions of Rio Grande do Sul.
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Respostas ecofisiológicas de Andropogon lateralis Nees subsp. lateralis (capim-caninha) : variação ecotípica ou plasticidade fenotípica? / Ecophysiological responses of andropogon lateralis nees Subsp. Lateralis (caninha grass) : ecotypic variation or Phenotypicplasticity?Porto, Claudia Beltrame January 2004 (has links)
Plasticidade fenotípica é a capacidade de um organismo alterar sua fisiologia e/ou morfologia em decorrência de suas interações com o meio, podendo resultar em uma maior tolerância às modificações ambientais. Tendo em vista que a seleção natural age sobre o fenótipo, a plasticidade fenotípica se caracteriza como um importante mecanismo gerador de variabilidade populacional. Em populações com grande potencial plástico pode ocorrer a formação de ecótipos, gerando populações geneticamente adaptadas às condições do seu local de origem. Este estudo teve como objetivo principal verificar a ocorrência de variações fenotípicas e a formação de ecótipos em duas populações de Andropogon lateralis subsp. lateralis do Rio Grande do Sul, provenientes de duas regiões fisiográficas, Depressão Central e Campos de Cima da Serra. As plantas foram cultivadas em casa de vegetação e avaliadas quanto a seus padrões de respostas fisiológicas, morfológicas e fenológicas a três níveis de adubação nitrogenada e a dois regimes hídricos. As populações apresentaram o mesmo padrão de resposta fotossintética, mas mostraram diferentes respostas quanto a atributos morfológicos, demonstrando diferenças em sua habilidade de responder às influências ambientais. Observou-se também uma assincronia temporal na floração das populações das duas regiões. Os resultados obtidos indicam a formação de ecótipos morfológicos para a espécie e a importância da variabilidade genética nos processos adaptativos e evolutivos nas regiões fisiográficas do Rio Grande do Sul. / Phenotypic plasticity is the capacity of an organism to modify its physiology andJor morphology as the result of interaction with the environment, which may result in an enhanced tolerance to environmental variation. Phenotypic plasticity generates populational variability, since natural selection acts on the phenotype. Ecotypes may appear among populations with significant plastic potential, which will then generate populations genetically adapted to the conditions of their habitats. The main aim of the present study was to verify the occurrence of phenotypic variations and the formation of ecotypes in two populations of Andropogon lateralis subsp. lateralis in Rio Grande do Sul, originating from two physiographic regions - the Depressão Central and Campos de Cima da Serra. The plants were grown in greenhouses and evaluated from the point of view of their physiological, morphological and phenological responses, first at three levels of nitrogen availability and second, under two sets of water availability conditions. The populations presented the same standard of photosynthetic response, but gave different responses regarding morphological attributes, thereby demonstrating differences in their ability to respond to environmental influences. Asynchronism of the flowering period was also noted in the populations from the two regions. The results obtained indicate the formation of morphological ecotypes with regard to the species and underline the importance of phenotypic plasticity in the adaptive and evolutive processes in the physiographic regions of Rio Grande do Sul.
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Biology and Energetics of Tropisternus Lateralis Nimbatus (SAY) (Coleoptera: Hydrophilidae) in a Playa on the Southern High Plains of Texas and Aquatic Coleoptera Diversity from Seven Playas on the Southern High Plains of TexasCook, Robert E. (Robert Edward), 1969- 12 1900 (has links)
A study of the biology of Tropisternus lateralis, a hydrophilid beetle, was conducted during the flood period of a single playa on the Southern High Plains of Texas from early June 1995 through early September 1995. Mechanism of colonization, tolerance/avoidance to drought, larval density, and secondary production were analyzed. T. lateralis colonized playas from surrounding aquatic habitats and avoided drought through aerial dispersion. Once in the playa, larval density increased over time. Secondary production was 1.31 g/m2/.25 yr. In addition, aquatic Coleoptera diversity was studied in seven playas on the Southern High Plains of Texas. A total of twenty three species were identified from the study region. Nine species not reported in playa literature were identified.
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A Domain That Assumes a Z-Conformation Includes a Specific Deletion in Some Cloned Variants of a Complex SatelliteFowler, Richard F., Stringfellow, Leslie A., Skinner, Dorothy M. 15 November 1988 (has links)
Sequence analyses show that deletions of 10 and 12 bp occur at homologous sites in a domain that is rich in alternating purines and pyrimidines (Pu/Py) in B42 and EXT, two cloned variants of a complex satellite DNA. A 3-bp deletion occurs 27 bp upstream from the site of the specific deletions in B42 and RU, a third cloned satellite variant that has not suffered the 10-bp deletion. Under torsional stress, the Pu/Py-rich domain adopts a Z-conformation as shown by (i) inhibition of cutting at a BssHII site that accounts for built2 5 of a 15-bp tract of pure Pu/Py in the domain; (ii) binding of polyclonal and monoclonal anti-Z-DNA antibodies to the domain; and (iii) antibody stabilization and subsequent relaxation of the Z-region.
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M. vastus lateralis EMG amplitud vid bilateral maximal knäextension utifrån träningserfarenhet : En tvärsnittsstudie / M. vastus lateralis EMG amplitude during bilateral maximal knee extension based on training experience : A cross-sectional studyKarlsson, Laban, Herrlander, Hilding January 2024 (has links)
Bakgrund: Det har tidigare undersökts hur muskelaktivering skiljer sig åt vid en unilateral (UL) och bilateral (BL) knäextension och observerats ett så kallat “Bilateral limb deficit” (BLD). Forskning saknas däremot kring hur BLD skiljer sig beroende på styrketräningserfarenhet. Syfte: Undersöka om elektromyografisk amplitud (EMGa) skiljer sig i m. vastus lateralis (VL) vid isokinetisk maximal knäextension mellan träningsgrupp (TrG) och icke-träningsgrupp (i-TrG). Metod: 6 kvinnor och 6 män rekryterades till studien. Studiedeltagarna delades i två grupper där en grupp hade utövat styrketräning regelbundet och den andra inte. EMGa och kraft mättes på deltagarna under en maximal isokinetisk knäextension i dynamometer. 6 mätningar utfördes på såväl dominant ben (DB) som icke-dominant ben (i-DB) vid 6 UL och 3 BL knäextensioner. Variablerna analyserades och jämfördes mellan grupperna. Resultat: Den genomsnittliga procentuella skillnaden i TrG var på DB 0% (±12.9) och på i-DB 0.7% (±10.8). I i-TrG var den genomsnittliga procentuella skillnaden på DB 21.3 (±11.9) och på i-DB 18.8 (±14.7). Den procentuella skillnaden mellan grupperna vid BL jämfört med UL muskelaktivering var signifikant i både DB (p=0.014) och i-DB (p=0.035). Vid BL knäextension jämfört med total UL kraft uppmätte TrG 1.5 % mindre kraft och i-TrG 17.5 % mindre kraft vid BL knäextension jämfört med total UL kraft. Kraftmomentet och EMGa visade stor korrelation (r=0.831, p=0.001). Konklusion: Studiens primära fynd indikerar att styrketräning minskar BLD. Detta har troligen sin grund i neural adaption men bekräftande orsak är oklar.
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Port-Orford-cedar and Phytophthora lateralis : grafting and heritability of resistance in the host, and variation in the pathogenMcWilliams, Michael G. 06 June 2000 (has links)
Port-Orford-cedar (Chamaecyparis lawsoniana) is a forest tree native to
a small area of Oregon and California. A root disease caused by
Phytophthora lateralis causes widespread mortality of Port-Orford-cedar.
This dissertation examines three important elements of the Port-Orford-cedar
P. lateralis pathosystem related to breeding for disease resistance:
use of resistant rootstocks to maintain genotypes of Port-Orford-cedar for
breeding; the heritability and genetic basis of disease resistance; and
variability in virulence and DNA fingerprint among a sample of P. lateralis
isolates.
Port-Orford-cedar was reciprocally grafted to western redcedar (Thuja
plicata), incense cedar (Calocedrus decurrens), and Alaska yellow-cedar
(Chamaecyparis nootkatensis). Port-Orford-cedar scion graft success was
moderate with western redcedar and incense cedar, but extreme
overgrowth of the rootstock by the scion indicated incompatibility. Xylem
union was good, but phloem union was incomplete or lacking. Nearly all
Port-Orford-cedar rootstocks and seedlings exposed to P. lateralis died of
root disease. Four percent of the Alaska yellow-cedar exposed also died,
confirming this tree as a host for P. lateralis.
Resistance of Port-Orford-cedar to P. lateralis is rare. A small number
of trees have been identified exhibiting resistance. A number of families
were tested to determine the genetic basis for resistance. Estimates of
narrow-sense and family mean heritability of resistance, as exhibited by
restriction of lesion length after inoculation, were determined. Both narrow-sense
and family mean heritabilities were between 0.61 and 0.98 in most
tests. Between 21% and 32% of the variance was due to differences
among families.
Thirteen isolates of P. lateralis were collected from three hosts
throughout the geographic range of the fungus. Variation in growth rate on
artificial media at three temperatures, virulence when used to inoculate
Port-Orford-cedar, and DNA fingerprint were compared. There were
significant differences in growth rate among isolates at 24C, but fewer
differences at lower temperatures and on a rich medium. One isolate
produced significantly shorter lesions in three different inoculation tests.
Isolates differed at only two of 189 bands produced by Inter Simple
Sequence Repeat (ISSR) DNA primers, indicating very little genetic
variation among isolates. / Graduation date: 2001
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