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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.
491

Swimming performance and energy homeostatic effects of uranium mill effluent exposure in small-bodied fish

Goertzen, Meghan Minetta 30 May 2011
Previous studies at the Key Lake uranium mill (Saskatchewan, Canada) suggested the complex effluent discharged alters energetic stores of resident fish species. A second study at the same site demonstrated certain fish from lakes downstream of the mill produce larvae with elevated incidence of developmental deformities. The mechanisms by which energy homeostasis is affected in fish downstream of the Key Lake uranium mill are unknown, and the effects of deformities and altered metabolism on swimming ability have not been explored. Therefore, the overall objective of this thesis was to investigate whether effluent exposed fish exhibited differences in swimming performance and energy homeostasis. To achieve this objective two experiments were conducted. In the first experiment juvenile spottail shiner (Notropis hudsonius) were collected from a lake downstream of the Key Lake uranium mill, and compared to fish collected from a nearby reference lake. In the second experiment larvae were collected from laboratory raised fathead minnow (Pimephales promelas) exposed to 5% diluted uranium mill effluent or control (dechlorinated municipal) water, and reared in the same treatments to 60 days post hatch (dph). No gross deformities were observed in any fish, and only shiner collected from the exposure lake in the field experiment had enlarged heart ventricles relative to body size compared to fish from the reference lake. Swimming performance was similar between shiner from the exposure and reference lakes in the field study, but effluent exposure impaired swimming ability in 60 dph fathead minnow in the laboratory experiment compared to fish from the control water treatment. After swimming performance tests fish were considered fatigued and metabolic endpoints were compared to non-fatigued fish. In both non-fatigued and fatigued shiner, liver glycogen was significantly greater in fish collected from the exposure lake compared to the reference lake. There was no difference in liver triglycerides in non-fatigued shiner between lakes, but liver triglycerides decreased after swimming in the field study reference fish. Muscle energy stores were unaffected by site or swimming in the field experiment. Conversely, whole body triglycerides and glycogen were similar between treatments in non-fatigued fathead minnow in the laboratory experiment. Swimming significantly decreased whole body triglycerides in fathead minnow from both treatments, but whole body glycogen was unaffected. In the field experiment blood endpoints (hematocrit, plasma glucose, lactate) in fatigued and non-fatigued shiner from both lakes further supported the possibility of altered intermediary metabolism or blunted stress response in fish downstream of the Key Lake uranium mill. In the field study, shiner muscle citrate synthase activity (an indicator of tissue aerobic capacity) was similar between lakes, but muscle âhydroxyacyl coenzyme A dehydrogenase activity (an indicator of tissue lipolytic capacity) was elevated. In contrast, laboratory fathead minnow whole body âhydroxyacyl coenzyme A dehydrogenase activity was similar between treatments, but citrate synthase activity was significantly lower in fathead minnow from the 5% effluent treatment. In summary, shiner from the exposure lake in the field experiment had similar swimming endurance and greater energy stores compared to fish from the reference lake, despite metabolic alterations. Fathead minnow from the 5% effluent treatment in the laboratory experiment had reduced swimming endurance that was matched by reduced whole body citrate synthase activity, but no other metabolic alterations were observed. Therefore, effluent exposure caused metabolic alterations in both fathead minnow and shiner, but specific effects between experiments were inconsistent. Overall, the physiological significance of the metabolic and swimming effects of effluent exposure is unclear, but suggests discharged effluent has the potential to negatively affect wild fish survivability.
492

Seguretat i higiene per les persones usuàries de les piscines cobertes i climatitzades de Catalunya

Escolà i Solà, Francesc 26 February 2013 (has links)
Per una banda les característiques pròpies de l’equipament, com són les condicions ambientals determinades o els paràmetres fisicoquímics concrets de l’aigua dels vasos, i per un altre costat les característiques implícites en el mateix ús, fan que les piscines cobertes i climatitzades siguin les instal·lacions esportives més complexes de gestionar des del punt de vista de la seguretat i la higiene. En els darrers anys les diferents administracions han generat una sèrie de normatives per legislar els aspectes relacionats amb l’ús de les instal·lacions esportives. Des de normes genèriques per a tots els edificis fins a normes específiques per a les piscines. Aquesta legislació posa a l’abast dels gestors prou eines per garantir la seguretat i la higiene dels usuaris. L’objectiu del present estudi ha estat comprovar quin és el grau de compliment de la normativa vigent en les piscines cobertes i climatitzades de Catalunya, mitjançant una entrevista al responsable de manteniment de les instal·lacions. / Por un lado las características propias del equipamiento, como son las condiciones ambientales determinadas o los parámetros fisicoquímicos concretos del agua de los vasos, y por otro lado las características que van implícitas con el mismo uso, hacen que las piscinas cubiertas y climatizadas sean las instalaciones deportivas más complejas de gestionar desde el punto de vista de la seguridad y la higiene. En los últimos años las diferentes administraciones han generado una serie de normativas para legislar aspectos relacionados con el uso de las instalaciones deportivas. Desde normativas genéricas a todos los edificios hasta normativas específicas para las piscinas. Esta legislación proporciona a los gestores suficientes recursos para garantizar la seguridad y la higiene de los usuarios. El objetivo del presente estudio ha sido comprobar el grado de cumplimiento de la normativa vigente en las piscinas cubiertas y climatizadas de Cataluña, mediante una entrevista con el responsable del mantenimiento de las instalaciones. / On the one hand, concerning the characteristics of the equipment, as are the environmental conditions determined or the concrete physical-chemical parameters of the water vessels.On the other hand, concerning the implicit characteristics in its use, make swimming pools which are covered and heated, the most complex sports facilities to maintain from a safe and hygienic point of view. In recent years, different governments have generated a series of regulations to legislate the aspects in reference to the use of the sports facilities. From general regulations for all the buildings to specific regulations of the swimming pools. This legislation provides enough tools for the management to guarantee the safety and hygiene of the users, which. The objective of this study has been to prove, to which degree, the current regulations complement the swimming pools in Catalunya which are covered and heated, through an interview with the head of maintenance of the sports facility.
493

Swimming performance and energy homeostatic effects of uranium mill effluent exposure in small-bodied fish

Goertzen, Meghan Minetta 30 May 2011 (has links)
Previous studies at the Key Lake uranium mill (Saskatchewan, Canada) suggested the complex effluent discharged alters energetic stores of resident fish species. A second study at the same site demonstrated certain fish from lakes downstream of the mill produce larvae with elevated incidence of developmental deformities. The mechanisms by which energy homeostasis is affected in fish downstream of the Key Lake uranium mill are unknown, and the effects of deformities and altered metabolism on swimming ability have not been explored. Therefore, the overall objective of this thesis was to investigate whether effluent exposed fish exhibited differences in swimming performance and energy homeostasis. To achieve this objective two experiments were conducted. In the first experiment juvenile spottail shiner (Notropis hudsonius) were collected from a lake downstream of the Key Lake uranium mill, and compared to fish collected from a nearby reference lake. In the second experiment larvae were collected from laboratory raised fathead minnow (Pimephales promelas) exposed to 5% diluted uranium mill effluent or control (dechlorinated municipal) water, and reared in the same treatments to 60 days post hatch (dph). No gross deformities were observed in any fish, and only shiner collected from the exposure lake in the field experiment had enlarged heart ventricles relative to body size compared to fish from the reference lake. Swimming performance was similar between shiner from the exposure and reference lakes in the field study, but effluent exposure impaired swimming ability in 60 dph fathead minnow in the laboratory experiment compared to fish from the control water treatment. After swimming performance tests fish were considered fatigued and metabolic endpoints were compared to non-fatigued fish. In both non-fatigued and fatigued shiner, liver glycogen was significantly greater in fish collected from the exposure lake compared to the reference lake. There was no difference in liver triglycerides in non-fatigued shiner between lakes, but liver triglycerides decreased after swimming in the field study reference fish. Muscle energy stores were unaffected by site or swimming in the field experiment. Conversely, whole body triglycerides and glycogen were similar between treatments in non-fatigued fathead minnow in the laboratory experiment. Swimming significantly decreased whole body triglycerides in fathead minnow from both treatments, but whole body glycogen was unaffected. In the field experiment blood endpoints (hematocrit, plasma glucose, lactate) in fatigued and non-fatigued shiner from both lakes further supported the possibility of altered intermediary metabolism or blunted stress response in fish downstream of the Key Lake uranium mill. In the field study, shiner muscle citrate synthase activity (an indicator of tissue aerobic capacity) was similar between lakes, but muscle âhydroxyacyl coenzyme A dehydrogenase activity (an indicator of tissue lipolytic capacity) was elevated. In contrast, laboratory fathead minnow whole body âhydroxyacyl coenzyme A dehydrogenase activity was similar between treatments, but citrate synthase activity was significantly lower in fathead minnow from the 5% effluent treatment. In summary, shiner from the exposure lake in the field experiment had similar swimming endurance and greater energy stores compared to fish from the reference lake, despite metabolic alterations. Fathead minnow from the 5% effluent treatment in the laboratory experiment had reduced swimming endurance that was matched by reduced whole body citrate synthase activity, but no other metabolic alterations were observed. Therefore, effluent exposure caused metabolic alterations in both fathead minnow and shiner, but specific effects between experiments were inconsistent. Overall, the physiological significance of the metabolic and swimming effects of effluent exposure is unclear, but suggests discharged effluent has the potential to negatively affect wild fish survivability.
494

The Effect Of Different Impact Exercise Training On Deformational Behavior And Functional Adaptation Of Articular Cartilage

Celik, Ozgur 01 January 2010 (has links) (PDF)
The objective of the present study was to investigate deformational behavior and functional adaptation of articular cartilage by comparing the changes of biochemical osteoarthritis markers&rsquo / concentrations due to 30-min exercise after 12-weeks of regular high impact, impact or non-impact exercise. Blood samples were drawn from 44 healthy sedentary males immediately before, immediately after and 0.5 h after a 30-min moderate walking exercise. Osteoarthritis biomarkers&rsquo / (Serum COMP and CTX-I) concentrations were determined with enzyme-linked immunosorbent assay. After the first measurements, participants were randomly assigned to running, cycling, swimming, and control groups. All groups except for control group trained for 12 weeks. After 12-weeks, post tests were applied. Multivariate tests indicated a significant fatigue and resting effect on serum COMP concentration in all groups at pre- and post-tests. Therefore, pair wise comparisons were conducted in order to assess the differences across all groups and conditions. Results indicated significant differences in post-test measurements among phases of groups except for running group. However, fatigue or resting did not change the concentration of serum CTX-I in any groups during the tests. According to results, moderate walking activity has an influence on the increase of serum COMP concentrations of young sedentary men. However, 12 weeks regular weight-bearing high impact physical exercise decreases the deformational effect of walking activity by functional adaptation of articular cartilage to specific environmental requirements.
495

Biological, simulation, and robotic studies to discover principles of swimming within granular media

Maladen, Ryan Dominic 08 November 2010 (has links)
The locomotion of organisms whether by running, flying, or swimming is the result of multiple degree-of-freedom nervous and musculoskeletal systems interacting with an environment that often flows and deforms in response to movement. A major challenge in biology is to understand the locomotion of organisms that crawl or burrow within terrestrial substrates like sand, soil, and muddy sediments that display both solid and fluid-like behavior. In such materials, validated theories such as the Navier-Stokes equations for fluids do not exist, and visualization techniques (such as particle image velocimetry in fluids) are nearly nonexistent. In this dissertation we integrated biological experiment, numerical simulation, and a physical robot model to reveal principles of undulatory locomotion in granular media. First, we used high speed x-ray imaging techniques to reveal how a desert dwelling lizard, the sandfish, swims within dry granular media without limb use by propagating a single period sinusoidal traveling wave along its body, resulting in a wave efficiency, the ratio of its average forward speed to wave speed, of approximately 0.5. The wave efficiency was independent of the media preparation (loosely and tightly packed). We compared this observation against two complementary modeling approaches: a numerical model of the sandfish coupled to a discrete particle simulation of the granular medium, and an undulatory robot which was designed to swim within granular media. We used these mechanical models to vary the ratio of undulation amplitude (A) to wavelength (λ) and demonstrated that an optimal condition for sand-swimming exists which results from competition between A and λ. The animal simulation and robot model, predicted that for a single period sinusoidal wave, maximal speed occurs for A/ λ = 0.2, the same kinematics used by the sandfish. Inspired by the tapered head shape of the sandfish lizard, we showed that the lift forces and hence vertical position of the robot as it moves forward within granular media can be varied by designing an appropriate head shape and controlling its angle of attack, in a similar way to flaps or wings moving in fluids. These results support the biological hypotheses which propose that morphological adaptations of desert dwelling organisms aid in their subsurface locomotion. This work also demonstrates that the discovery of biological principles of high performance locomotion within sand can help create the next generation of biophysically inspired robots that could explore potentially hazardous complex flowing environments.
496

Dermal absorption of a dilute aqueous solution of malathion [electronic resource] / by John E Scharf.

Scharf, John E. January 2003 (has links)
Document formatted into pages; contains 78 pages. / Title from PDF of title page. / Thesis (M.S.P.H.)--University of South Florida, 2003. / Includes bibliographical references. / Text (Electronic thesis) in PDF format. / ABSTRACT: Malathion is a commonly used organophosphate pesticide on field crops, fruits, nut trees, vegetables, livestock, agricultural premises, and land. The approved uses also include mosquito and medfly control. These uses can result in human skin contact. The purpose of this study is to evaluate the human skin absorption of malathion for the purpose of assessing the risks associated with aqueous solution exposures following applications. Aerial applications can result in solubilized malathion in swimming pools and other waters that may be contacted. Human volunteers were selected and exposed to aqueous solutions of malathion at various concentrations. Participants submerged their arms and hands in twenty liters of dilute malathion solution in either a stagnant or stirred environment. The "disappearance method" was applied by measuring malathion concentrations in the water before and after human subject exposure to the water for various periods of time. Malathion was measured using Gas Chromatography. No measurable skin absorption was detected in 42% of the participants. Measurable skin absorption among the remaining 58% of participants resulted in doses that were more than an order of magnitude less than the minimal dose necessary to cause a measurable change in red blood cell acetylcholinesterase (RBC-AChE). Extrapolation of these results to a mathematical model for recreational swimmers and bathers exposed to contaminated swimming pools and surface waters typically detected after bait application again are an order of magnitude below the doses needed to cause a detectable change in RBC-AChE. These data indicate that exposure to aqueous malathion following usual aerial bait applications is not appreciably absorbed, and therefore, it is not a public health hazard. / System requirements: World Wide Web browser and PDF reader. / Mode of access: World Wide Web.
497

Making a Splash: Eliminating Water Phobia and Increasing Confident Water Skills

Chan, Paula Elizabeth 01 January 2011 (has links)
The purpose of this study was to utilize a multi-component intervention to increase confident water skills for three typically developing children, and to evaluate whether fearful behaviors decreased as the intervention progressed. The intervention, comprised of goal setting, self-monitoring, behavioral skills training and positive reinforcement, was used in community pools to teach basic water skills. Results suggest the intervention was successful in increasing confident water skills, while intervals with positive affect and fearful behaviors demonstrated variability.
498

Επίδραση της θερμοκρασίας στην κολυμβητική ικανότητα, αύξηση και επιβίωση του σαργού [Diplodus sargus sargus (Linnaeus 1758)] και του μελανουριού [Oblada melanura (Linnaeus 1758)] κατά τη φάση της μεταμόρφωσης και "εγκατάστασης"

Αγγελοπούλου, Αγγελική 29 July 2008 (has links)
Στην παρούσα εργασία μελετήθηκε α) η επίδραση της θερμοκρασίας άσκησης στην κολυμβητική ικανότητα των μεταμορφούμενων ατόμων σαργού (Diplodus sargus) και μελανουριού (Oblada melanura), β) η συμβολή των μυών και του σχήματος του σώματος στην κολυμβητική ικανότητα κάθε είδους, και γ) η επίδραση της θερμοκρασία διαβίωσης στο ρυθμό αύξησης και επιβίωσης κάθε είδους. Τα αποτελέσματα της παρούσας εργασίας συζητούνται ως προς τη σημασία της κολυμβητικής ικανότητας κατά τη φάση της μεταμόρφωσης, καθώς και συγκριτικά με τα αποτελέσματα άλλων εργασιών για την επίδραση της θερμοκρασίας στην ταχύτητα κολύμβησης, στο ρυθμό αύξησης και επιβίωσης των ψαριών. / The present study examined a) the effect of exercise temperature on swimming performance of white seabream (Diplodus sargus sargus) and saddled seabream (Oblada melanura) juveniles, b) the contribution of muscles and body shape on swimming performance of each species and c) the effect of temperature on growth rate and survival of each species. The results of the present study are discussed with respect to the importance of swimming performance during the metamorphosis stage and are compared to the results of other studies concerning the effect of temperature on swimming speed, growth rate and survival of fish.
499

Swimming in four goldfish (Carassius auratus) morphotypes: understanding functional design and performance through artificial selection

Li, Jason 05 1900 (has links)
Although artificially selected goldfish exhibit swimming performance decrements, with the most derived morphotypes more affected, they can be utilized to explore functional design and movement pattern principles in aquatic vertebrates. Drag, steady swimming kinematics (tailbeat frequency, amplitude, stride length), energetics (standard and active metabolic rate), fast-start performance (average and maximum velocity and acceleration), stability in yaw and roll and propulsive muscle ultrastructural characteristics (mitochondrial volume density and spacing, myofibril diameter and capillary to fibre ratio in red and white muscle) were measured for four morphotypes: common, comet, fantail and eggfish, of comparable length (≈ 5 cm). A performance “pairing” (common and comet; fantail and eggfish) was a recurrent theme for most performance parameters. Vertebral numbers (30), segment lengths (≈ 0.85 mm) and standard metabolic rates (≈ 140 mg O2 kg-1 hr-1) are exceptions where values are the same. Fantail and eggfish drag and drag coefficients (referenced to frontally projected area ≈ 0.6 - 0.9) were higher (requiring more thrust at any given velocity) than those for the more streamlined common and comet (≈ 0.3 - 0.6; P < 0.05). This is reflected in kinematics; tailbeat frequency and stride length at any given velocity for the common and comet are lower and higher respectively than that of the fantail and eggfish (P < 0.05). Common and comet fatigue times are not significantly different from that of their ancestor, Crucian carp (P > 0.05), and are lower than those of the fantail and eggfish (P < 0.05). The cost of transport of the common and comet (≈ 0.6 mg O2 kg-1 m-1) is accurately predicted from the mass scaling relationship for fish (P > 0.05), but values for the fantail and eggfish (≈ 1.3 mg O2 kg-1 m-1) are not (P < 0.05). Eggfish steady swimming (dorsal fin absent) was characterized by rolling and yawing motions associated with significant energy losses. Common and comet fast-start performance (average velocity ≈ 0.45 m s-1, maximum velocity ≈ 1.2 m s-1, average acceleration ≈ 7.5 m s-2, maximum acceleration ≈ 35 m s-2) was similar to that of other locomotor generalists (e.g. trout). Eggfish maximum acceleration (≈ 5 m s-2) is poor due to the absence of inertial and lifting contributions to thrust from the dorsal fin and energy wasting rolling motions. Artificially selected fish can bear upon fitness related adaptations associated with form and movement, providing insights into the “performance envelope” of natural systems subject to ecological speciation.
500

The effects of moderate swimming exercise on immune system function in C57 BL/6(B6) mice /

Hoyeck, Edward. January 2000 (has links)
The purpose of this study was to separate acute and chronic effects of moderate exercise on the immune system by analyzing three sets of experimental and control groups; (1) 72 hours, (2) 1 week, (3) 2 weeks post exercise. Mice swam 5 days per week for 3 weeks accumulating a total of 125, 225, and 225 minutes of exercise in weeks 1, 2, and 3, respectively. Moderate swimming exercise did not result in a significant increase in SDH levels (p > 0.05). There was no change in tissue cell responses as measured by mitogen responsiveness, nor in splenic and thymic cell counts in response to the training regimen at any time point (p &ge; 0.05). Total, CD4, CD8, and T cell counts in the lymph nodes were significantly suppressed at 72 hours and 2 weeks post exercise (p &le; 0.05). It appears that chronic exercise resulted in an increased trafficking of lymphatic cells, which could be interpreted as a sign of heightened immune reactivity.

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