Diss. (sammanfattning) Linköping : Univ., 2001. / Härtill 5 uppsatser.

Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 5 uppsatser.

Twenty-one male subjects volunteered to participate in this study of the effects of an u1tramarathon run under competitive conditions. Selected anthropometric measurements were made before and after the race. Blood samples were taken before, and within 10 min. of completing the race. Haematocrit and cortisol concentrations were analysed from each sample. Three ratings of perceived exertion (RPE) - local, central and overall, were obtained at two-hourly intervals throughout the race. The shortened form of the Eysenck Personality Inventory (EPI) was administered before the race. The Profile of Mood States (POMS) test was completed both before and immediately after the race. The average running intensity was estimated to be about 32% VO₂max which would not have caused major lactate accumulation. Repetitive compressive forces as a result of heel-strike resulted in intervertebral disc fluid loss. This resulted in a significant (p<0.05) decrease in stature after the race. Mobilization of glycogen, trig1ycerides and protein for metabolism as well as fluid loss via sweat resulted in significantly decreased body mass after the race. Plasma volume and serum cortisol concentrations were significantly increased after the race compared to pre-race baseline levels. Local RPE responses were dominant throughout the entire race, followed by overall RPE. Running 160 km had an effect on mood state. "Depression", "fatigue" and "confusion" (profile of Mood states) were all significantly increased compared to pre-race scores. Sleep deprivation as a result of running through the night was probably an important contributing factor. The anthropometric profile of the ultramarathon runners in this sample was more like that of the general population than elite marathon runners from the literature. The ultramarathon runners were more extroverted than elite marathon runners, but exhibited a similar Profile of Mood state before the race. The stressor - running 160 km - resulted in a 'strain response'. This was evident in the decreased stature and mass, and increased serum cortisol, "depression", "confusion" and above all "fatigue".

M.Sc. / There has been an increasing concern worldwide regarding the possible adverse effects of pharmaceutical supplements present in our aquatic ecosystems and whether or not they modify or alter physiological functioning in humans and wildlife. Trenbolone acetate (TBA) for example, is a commonly used androgenic anabolic steroid used in the production of cattle. TBA is metabolized into trenbolone-β and excreted as both trenbolone-α and -β. In liquid manure trenbolone-β has a half-life of over 270 days. Therefore if released into the surrounding environment there could be severe ecological impacts. The aim of this study was to determine the physiological effects of hormones used as growth stimulants in cattle production on the Sharptooth Catfish - Clarias gariepinus. The growth stimulants assessed in this study included; Trenbolone acetate, Methyltestosterone, Diethylstilbestrol and Zeranol. The aim was pursued with the use of three biomarker assays - Glutathione-S-transferase (GST), Uridine-Diphosphate Glucuronosyltransferase (UDPGT) and Cellular Energy Allocation (CEA). Fish were exposed under controlled conditions for a period of 5, ten and 15 days respectively using a flow-through system. Testes were removed and standard histological techniques were employed. Selected target organs were removed and immediately frozen in liquid nitrogen and stored at -80°C until needed for biomarker analysis.The results obtained from the gonado-somatic Index (GSI) showed that there were no significant differences (p<0.05). The hepato-somatic index (HSI) increased throughout all the different exposure groups. The histological assessment showed no significant alterations in the cell structure of the testes. With regards to the biomarkers used, CEA reflected changes in both the energy available and the energy consumed by the test organisms during the exposures. A common trend was observed throughout the different exposures. A change would occur after the ten day exposure period however a recovery would be made after 15 days of exposure. Both GST and UDPGT reflected increased activity in the liver with GST reflecting a significant difference (p<0.05) between the control and the exposure groups, however GST activity in the kidneys were not affected. To conclude, further studies will be needed to determine whether or not these growth stimulants will have a significant effect at higher concentrations and over longer exposure periods.

The aims of the research were to establish whether diphenylhydantoin and phenobarbitone are teratogenic in mice both in vivo and in an in vitro whole embryo culture system, to investigate possible mechanisms of teratogenicity and to examine whether the methods used in this study, may form a basis for developing systems of more extensive drug teratogenicity screening.

No description available.

Traffic noise has been shown to have negative effects on exposed persons in the communities along highways. Noise from transportation systems is considered a nuisance in the U.S. and the government agencies require a determination of noise impacts for federally funded projects. There are several models available for assessing noise levels impacts. These models vary from simple charts to computer design models. Some computer models, i.e. Standard Method In Noise Analysis (STAMINA), the Traffic Noise Model (TNM) and the UCF Community Noise Model (CNM), have been used to predict geometric spreading, atmospheric absorption, diffraction, and ground impedance. However, they have largely neglected the atmospheric effects on noise propagation in their algorithms. The purpose of this research was to better understand and predict the meteorological effects on traffic noise propagation though measurements and comparison to acoustic theory. It should be noted that this represents an approach to incorporate refraction algorithms affecting outdoor noise propagation that must also work with algorithms for geometric spreading, ground effects, diffraction, and turbulence. The new empirical model for predicting atmospheric refraction shows that wind direction is a significant parameter and should be included in future modeling for atmospheric refraction. To accomplish this, the model includes a "wind shear" and "lapse rate" terms instead of wind speed and temperature as previously needed for input of the most used models. The model is an attempt to explain atmospheric refraction by including the parameters of wind direction, wind shear, and lapse rate that directly affect atmospheric refraction.

Prior research has established trickle-down effects (including trickle-out effects) in organizations, that is, perceptions, attitudes, and behavior may flow downward from an individual at a higher level of the organizational hierarchy (e.g., a supervisor) to another individual at a lower hierarchical level (e.g., a frontline employee), or from a frontline employee to an external member (e.g., a customer). Complementing the extant literature, this dissertation examines trickle-in effects, specifically, I examine whether customers' interpersonal and organizational deviance behavior will trickle-in through organizational boundary to influence a frontline employee's interpersonal and organizational deviance behavior. Specifically, I propose customers' interpersonal and organizational deviance behavior will trickle-in through organizational boundaries to affect employees' interpersonal and organizational deviance behavior. In addition, I develop a multiple-mediator model to test the different possible mechanisms underlying trickle-in effects: social exchange, social learning, displaced aggression, self-regulation, and social interactionist model. Two studies were conducted to test my propositions. In retail settings, Study 1 finds customers' interpersonal deviance behavior trickled-in through organizational walls to influence employees' interpersonal and organizational deviance behavior through displaced aggression mechanism. Study 2, collecting data from call centers, demonstrates customers' organizational deviance behavior trickled-in to influence employees' organizational deviance behavior through social learning processes.

Nowadays, asphalt mixtures can be complex and have many ingredients to meet economic, performance, and/or environmental requirements. Economic and environmental factors have been driving performance in the positive direction for rutting, but the negative direction for brittleness, cracking, and overall durability. Recent research has also shown that two of the national standards to assess aging or effects of environmental factors (AASHTO T283 and R30) do not always simulate the amount of aging or behaviors mentioned in the documents. Also, these methods generally view one environmental effect at a time, and do not consider simultaneous environmental effects on aging (e.g. oxidation, moisture, freeze-thaw effects). However, pavements are exposed to combined environmental effects. As such, there is a lack of understanding of the combined environmental effects on asphalt pavement, and improve methods are needed for laboratory settings, resulting in less than optimal design and materials selection protocols. This dissertation focuses on investigating combined environmental effects of oxidation, moisture, and freeze-thaw. The dissertation includes four years of field aging of plant mixed asphalt mixtures containing no recycled materials and three different warm mix technologies that were also exposed to eight laboratory conditioning protocols including individual and combined environmental effects of oxidation, moisture and freeze-thaw to investigate mixture properties measured at high, intermediate, and low temperatures with several mixture tests that were complimented with tests on recovered binder. Major findings are summarized below: • Cantabro mass loss captured individual and combined effects damage in laboratory and field conditions better than other mixture testing utilized herein and was recommended for mixture assessment. • Laboratory conditioning protocols with combined effects were the only ones able to consistently represent four or more years of field aging in the Mississippi climate. • Field aging of laboratory compacted specimens in PVC sleeves did not fully represent field aging of field placed pavement. Temperature and moisture conditions varied between the two cases. • Use of Cantabro mass loss and laboratory conditioning consisting of hot air, hot water, and freeze-thaw conditions was shown to provide combined effects improvements relative to at least some typical practices. Guidance was provided on how to use these tools to assess combined effects.

The tobacco cyst nematode [Globodera tabacum solanacearum (Miller & Gray, 1972) Behrens, 1975] is an important pathogen affecting flue-cured tobacco (Nicotiana tabacum L.) in Virginia, North Carolina, and Maryland. The resistant cultivars Coker 371 Gold and Kutsaga 110 were evaluated during 1999 and 2000 in the greenhouse to determine the mode of inheritance of resistance to the tobacco cyst nematode (TCN). Each cultivar was crossed to the susceptible cultivar K 326 and F1 progeny were backcrossed to each parent. Plants from each parent and F1, F2, BC1Ps, and BC1Pr progeny were evaluated for TCN resistance. Six-week-old transplants were inoculated with 6000 TCN eggs from crushed cysts. Eight weeks after inoculation, a 1-g sample of fibrous root was stained and vermiform, swollen, pyriform, and adult nematodes were counted. The number of cysts and eggs per 400 cm3 of soil were counted from each transplant. Generation means analyses were performed. Additive and dominance gene action play an important role in resistance to TCN in Coker 371 Gold and Kutsaga 110. F2 generation data from the Coker 371 Gold cross fit a 3:1 (resistant:susceptible) segregation ratio and BC1Ps generation data fit a 1:1 segregation ratio, indicating that resistance to TCN is conferred by a single dominant gene. A continuous range of variation was observed among the F2 progeny for the K 326 X Kutsaga 110 cross, indicating resistance in Kutsaga 110 is quantitative. TCN resistance in Coker 371 Gold and Kutsaga 110 may be derived from different sources. / Master of Science