<p>This thesis compares different methods for risk assessment of a creosote contaminated site in Vansbro, Dalarna. In a complementary study the importance of using representative data for calibration and validation of stationary groundwater models is discussed. The time dependency between surface water levels and groundwater levels on the site in Vansbro is evaluated by step response analysis. The results show that the groundwater levels reflect only long-term variation in the surface water levels. Hence the use of such long-term means for calibration and validation of the stationary groundwater models is the only theoretically defendable alternative.</p><p>As a first step in the comparison of risk assessment methods the degree of contamination is evaluated on the basis of generic guideline values for contaminated soils, developed by the Swedish Environmental Protection Agency. The guidelines specifically developed for contaminated petrol stations are also taken into consideration. Secondly, a site-specific evaluation is carried out. The transport of contaminants from the soil to the on-site groundwater and nearby surface water is calculated using the mathematical models behind the aforementioned guideline values. The calculated groundwater concentrations show a poor agreement with observed data and the thesis points out several possible explanations of this deviation. A sensitivity analysis is carried out and the influence of biodegradation during the transport in the aquifer is evaluated. The results indicate that the deviation between observed and calculated groundwater concentrations cannot be explained by the absence of biodegradation in the mathematical models, but rather by other simplifications and uncertainties in estimated model parameters.</p><p>Finally, a risk assessment is made on the basis of observed groundwater concentrations instead of observed soil concentrations as in the assessments above. Observed groundwater concentrations are compared with guideline values for groundwater on contaminated sites. The risk of negative environmental effects in the surface water is evaluated based on the estimated inflow of contaminated groundwater and its concentration of contaminants. The inflow is estimated from the interpolation of observed groundwater levels as well as with two numerical groundwater models of varying hydrogeological complexity: a three-dimensional flow model developed in Visual MODFLOW and a two-dimensional flow model developed in TWODAN. The models are compared with respect to the calculated inflows of contaminated groundwater into the surface water body as well as their ability to reproduce observed groundwater levels. The results indicate that the differences between the models, with respect to the calculated inflows, are of lesser importance to the risk assessment in comparison with the uncertainties associated with other parameters. The choice to base the assessment on observed contaminant concentrations in either the soil or the groundwater is shown to be of crucial importance.</p> / <p>I detta examensarbete jämförs olika metoder att bedöma de hälsomässiga och miljömässiga risker som föreligger med ett kreosotförorenat markområde i Vansbro, Dalarna. I en kompletterande undersökning belyses vikten av att stationära grundvattenmodeller kalibreras och valideras mot tidskompatibla indata. Tidsberoendet mellan yt- och grundvattennivåer på området i Vansbro studeras genom stegsvarsanalys. Resultaten visar att grundvattennivåerna på området anpassar sig mycket långsamt efter rådande ytvattennivåer. Grundvattennivåerna återspeglar således medelvärden av ytvattennivåerna över en mycket lång tidsperiod. Därför är användandet av sådana medelvärden för kalibrering och validering av modellerna det enda teoretiskt försvarbara alternativet.</p><p>Som ett första steg i jämförelsen mellan olika riskbedömningsmetoder utvärderas föroreningssituationen baserat på uppmätta föroreningskoncentrationer i jorden och med hjälp av Naturvårdsverkets generella samt branschspecifika riktvärden för förorenad mark. Därefter genomförs en platsspecifik riskbedömning. Föroreningstransporten från markområdet till grundvattnet samt till ett närbeläget ytvatten beräknas med de matematiska modeller som användes av Naturvårdsverket vid framtagandet av ovannämnda riktvärden. Beräknade grundvattenkoncentrationer jämförs med uppmätta koncentrationer och resultaten visar på stora avvikelser. En känslighetsanalys utförs och inverkan av biologisk nedbrytning i akviferen utvärderas. Resultaten tyder på att avvikelsen mellan uppmätta och beräknade grundvattenkoncentrationer ej förklaras av att biologisk nedbrytning inte beaktas i modellerna utan att avvikelsen härrör från andra förenklingar och från osäkerheter i indata.</p><p>Slutligen genomförs en platsspecifik riskbedömning, motsvarande den ovan, men denna gång utifrån uppmätta föroreningskoncentrationer i grundvattnet. De uppmätta grundvattenkoncentrationerna jämförs direkt mot Naturvårdsverkets riktvärden för grundvatten på förorenade områden. Risken för negativa ekologiska effekter i ytvattnet utvärderas utifrån det beräknade inflödet av förorenat grundvatten samt dess koncentration. Inflödet beräknas överslagsmässigt utifrån interpolerade grundvattennivåer samt med två numeriska grundvattenmodeller av olika hydrogeologisk komplexitet: en tredimensionell flödesmodell uppbyggd i Visual MODFLOW och en tvådimensionell modell uppbyggd i TWODAN. Grundvattenmodellerna jämförs med avseende på det beräknade inflödet och med avseende på deras förmåga att beskriva observerade grundvattenförhållanden.Resultaten tyder på att skillnaden i det, med de olika metoderna, beräknade inflödet är av liten betydelse för riskbedömningen i förhållande till osäkerheter förknippade med övriga parametrar. Störst betydelse för riskbedömningen får valet att utgå från uppmätta föroreningskoncentrationer i antingen jorden eller grundvattnet.</p>

To determine whether extreme endurance exercise induces lipid peroxidation, we studied 14 athletes (5 females: 9 males) during a 50 km ultramarathon (trial 1) and during a sedentary protocol (trial 2) one month later. At dinner the evening before the race (or sedentary trial), subjects consumed vitamin E labeled with stable isotopes (75 mg each d₃-RRR and d₆-all rac-α-tocopheryl acetates). Blood samples were taken at baseline, 30 minutes pre-race, mid-race, post-race, 1 h post-race, 24 h post-race, and at corresponding times for each individual during trial 2. During the sedentary day of trial 2, subjects consumed the same amounts of race day foods, including ergogenic aids, that they had consumed in trial 1; vitamin E intakes were 77 ± 40 mg, and vitamin C 406 ± 169 mg. All 14 subjects completed the race; average time to completion was 390 ± 67 minutes. Plasma F₂-isoprostanes (F₂-I), labeled and unlabeled α-tocopherol, and ascorbic acid (AA) were measured. F₂-I increased from 76 ± 24 pg/ml pg/ml at pre-race to 117.4 ± 38.0 pg/ml (p<0.0008) at mid-race to 130 ± 54 pg/ml (p<0.0001) at post-race, then returned to baseline at 24 hours post-race; F₂-I were unchanged during trial 2. Deuterated d₃ α-tocopheryl (d₃ α-Toc) disappearance rates were faster (2.8x10⁻⁴ ± 0.5x10⁻⁴) during the race compared to the sedentary trial (2.3x10⁻⁴ ± 0.6x10⁻⁴; p < 0.03). Plasma AA increased from 75.2 ± 11.2 μM at pre-race to 157.7 ± 36.2 μM at race end (p<0.0001) and decreased to below baseline concentrations at 24 h post-race (40.4 ± 5.2 μM p<0.0001). AA levels also increased during trial 2. Despite increased plasma AA, F2-I increased during exercise, but not during the sedentary period. Additionally, vitamin E disappeared faster during the run compared to the sedentary protocol. Thus, extreme endurance exercise results in the generation of lipid peroxidation and increased vitamin E utilization. / Graduation date: 2001

While there is growing public concern over the safety of the food supply, few studies have contrasted varying perceptions of pesticide risk. This study assessed and contrasted perceptions of three groups of Oregon State University Extension Service clientele (home food preservers, Master Gardener volunteers, commercial growers) and factors influencing these perceptions. The impact of the pesticide risk perceptions on purchasing decisions and pesticide application practices was assessed. Two questionnaires were developed: one for home food preservers/Master Gardener volunteers and one for commercial growers. One hundred twenty-seven questionnaires were completed by a convenience sample of home food preservers (85% adjusted return rate) and 155 questionnaires were completed by randomly selected Oregon State University Master Gardener volunteers (81% adjusted return rate). A shortened version of the questionnaire was completed by 124 participants at the annual meeting of Willamette Valley Processed Vegetable Growers. Home preservers were 84% female (mean age=49 ± 14 years), volunteers were 50% female/50% male (mean age=56 ±14 years), and commercial growers were 95% male (mean age=42 ± 11 years). Three different measures of pesticide risk perceptions were used to test six hypotheses: Respondents rated 1) "eating foods produced using pesticides" as high, low, or no risk, and agreed/disagreed (on Likert scales) whether 2) "chemical residues remaining on produce are a major health concern," and 3) "children are at a greater risk for illness from pesticides than adults." Produce selection decisions, pesticide application practices, life stages, gender, media awareness, and knowledge of agricultural production techniques and practices were also assessed to determine their relationship with risk perceptions. Perceptions of risk varied among the three groups. Fifty-five percent of preservers rated "eating foods produced using pesticides" as a "high" risk compared to 34% of volunteers and 2% of growers. Thirty-four percent of preservers strongly agreed that "chemical residues remaining on produce are a major health concern" compared to 25% of volunteers and 7% of growers. Forty-six percent of preservers strongly agreed that "children are at a greater risk of illness from pesticides than adults" compared to 42% of volunteers. Fifty-two percent of growers strongly/ somewhat agreed that children are at no greater risk. Gender was significantly associated with respondents' perceptions. Eighty-nine percent of preservers rating the risk of "eating food produced using pesticides" as "high" were female as were 65% of volunteers. Female volunteers moderately agreed that "chemical residues remaining on produce are a major health concern" compared to males who tended to neither agree nor disagree. The presence of children living in the home was significantly related to the volunteers' perceptions that chemicals are a major health concern and that children are at greater risk. Preservers and growers' results indicated there were no significant differences. Awareness of pesticide reports in the media was measured by recall of four media events. Media awareness was significantly associated with preservers' perceptions that eating foods produced with pesticides was "high" risk and that children are at a greater risk for illness because of pesticide residues. There was no media association for either volunteers or growers. Influence of risk perceptions on produce purchase decisions was measured with a series of questions about past, present, and future purchases. Results indicated that volunteers' pesticide risk perceptions were significantly related to more produce selection decisions than were home food preservers. The risk perception measure that "chemical residues remaining on produce are a major health concern" was most significantly associated with purchase decisions for both preservers and volunteers. For preservers and volunteers there were significant relationships between all three measures of pesticide risk perceptions and three of the twelve purchase decisions tested. Those who perceived a higher risk were 1) more willing to pay a higher price for certified residue free produce, 2) more concerned about pesticide residues when buying imported produce, and 3) intended to purchase produce grown without synthetic pesticides even if it costs more. Knowledge of agricultural practices was measured by a set of five questions. Mean scores ranged from 0.9 ± 0.9 for preservers to 1.6 ± 1.0 for volunteers out of a possible 5.0. Volunteers' with higher scores were significantly more likely to agree that chemicals are a major health concern and that children are at a greater risk of illness from pesticide residues. No significant associations were seen for preservers. Pesticide application practices were significantly related to pesticide risk perceptions. Preservers and volunteers who generally perceived the risks as "high" reported not using pesticides. Preservers reporting changes in application practices moderately agreed chemical residues are a major health concern while volunteers' reporting changes in application practices strongly agreed that children are at higher risk than adults. Growers tended to disagree that pesticides are a major health concern and they were less concerned that children are at a greater risk from pesticides. The study concluded that the home food preservers and Master Gardener volunteers perceived the risks associated with pesticides and produce as much higher than commercial vegetable growers. This difference in perceptions is reflected in some of their produce selection decisions and pesticide application practices. Children living at home, gender, media awareness, and knowledge of agricultural practices were associated with the pesticide risk perceptions of these Extension clientele. Results suggest that educational programming to increase knowledge about pesticide usage in agricultural production is warranted. There is also a need to foster better communications among groups with differing points of views about pesticide residue risks. / Graduation date: 1994

Research on the factors underlying sex offender recidivism has not considered the importance of the reintegration process through which the offender rejoins the community after prison. This thesis reports findings from 3 empirical studies designed to explore whether poor release planning might contribute to sex offender recidivism. In Study 1, a coding protocol was developed to measure the comprehensiveness of release planning for child molesters, which included items relating to accommodation, employment, pro-social support, community-based treatment, and Good Lives Model (T. Ward & C.A. Stewart, 2003) secondary goods. The protocol was retrospectively applied to groups of recidivist and nonrecidivist graduates of a prison-based treatment programme, who were matched on static risk level and time since release. As predicted, overall release planning was significantly poorer for recidivists compared to nonrecidivists. Study 2 was a validation and extension of Study 1. The original coding protocol, and some revised items, were applied to matched groups of recidivists and nonrecidivists from a different treatment programme. Consistent with Study 1 findings, overall release planning was significantly poorer for recidivists. Data from Studies 1 and 2 were pooled (total N = 141) and Cox regressions showed that accommodation, employment, and social support planning combined to best predict recidivism, with predictive accuracy comparable to that obtained using static risk models. Study 3 investigated whether release planning was associated with actual reintegration experiences, and additionally explored released child molesters’ good lives plans. Release plans were rated for 16 child molesters, who were interviewed post-release about their reintegration experiences and good lives plans. As predicted, significant positive correlations were found between release planning and reintegration experiences 1 and 3 months following prison release, and results suggested that effective reintegration might help facilitate living a good life. Overall, results from the 3 studies suggest that poor release planning and subsequent reintegration experiences contribute to sex offender recidivism. Implications for researchers, clinicians, policy makers, and community members are discussed.

Most of the main determinants of water quality either consist of, or are controlled by, particles. Previous water quality research has focused on particular particles in isolation or in binary combinations. In this project, we are taking a holistic approach to the characterization of the particle load in water, focusing on the collective properties of the particles rather than individual components. Because the characterization of particles is often time-consuming, applying an informatics-based approach could speed up the evaluation of water quality and the assessment of treatment effectiveness. Further, the breadth of potential changes that could be detected using this multiplex approach may far surpass the abilities of current approaches to monitor threats to water quality. Among the instruments capable of rapidly detecting and manipulating cells is imaging flow cytometry, which distinguishes cell shape and unique fluorescence properties associated with cell types. Sets of images and corresponding data from a 1.5-year time series of samples from the Columbia River were studied and the different particle properties analyzed. Principal Component Analysis (Empirical Orthogonal Function analysis) was applied in order to reduce the number of variables and identify patterns in particle characteristics when compared to environmental data collected from the observation station. The first three principal components were extracted and the dominant characteristics identified: the most prominent variables are particle size, particle color, and fluorescent qualities (transparency and phytoplankton pigments). Further work will relate these top principal components to specific environmental factors that determine water quality.

The Purpose of this research was to describe relationships between Murdaugh and Verran's (1987) Preventive Behavior Model Concepts in military-affiliated individuals at risk for coronary artery disease. One hundred forty-three subjects were recruited by their primary care physician and were requested to voluntarily complete questionnaires measuring health beliefs, health locus of control, value orientations, and health care activities. Laboratory values and blood pressure were also evaluated. There were significant positive correlations between health beliefs, health locus of control, and value orientations. However, these PBM concepts explained only 13% of the variance in dietary habits, 9% of smoking behaviors, 16% of habitual physical activity, 4% of cholesterol levels, 2% of diastolic blood pressure, 7% of body mass index, and 21 percent of glucose levels. PBM concepts explained a relatively small amount of the variance in the dependent variables within this sample and the results were not clinically significant.

No description available.

<p>Physical inactivity is one of the leading risk factors for major non-communicable diseases, which contribute substantially to the global burden of chronic diseases, disability and death. The burden of disability, morbidity and mortality, attributable to non-communicable diseases, is currently enormous in the developed countries and is increasingly growing in the developing countries. The purpose of this study was to investigate the relationship between participation in physical activity and health risk behaviours among high school students in the Mtwara region, Tanzania. The objectives of this study were to identify the physical activity levels among high school students in Mtwara region, Tanzania, to identify health risk behaviours among the above mentioned high school students, to identify the factors that influenced them to engage in health risk behaviours and to establish the relationship between physical activity and health risk behaviours.</p>

Young children are particularly sensitive to environmental pollutants. They can directly ingest soil by putting dirty hands and objects in their mouths. The reliance on animal derived models for human health risk and exposure assessment has several limitations. In this investigation, a tool-kit was developed and optimised to facilitate more accurate, reliable and representative predictions of soil contaminants that might pose a significant hazard to young children. The tool-kit was developed and optimised using an in vitro human digestion bioassay. This procedure was followed by the optimisation of several mutagenicity bioassays to link to the bioaccessible fraction which quantified by the in vitro bioassay. The application of novel and sensitive environmental-based biosensors requires them to work in parallel with effective and proven extraction techniques. In this study, chemical analysis was used to quantify the bioaccessible (human assimilated portion) of pollutants in soils. Acute toxicity was measured using constitutively marked bioluminescent bacterial biosensors and these were indicative of the total contaminant burden. A range of mutagenic assays were applied and optimised. In the Ames assay, any compound exhibiting a greater than two-fold increase in the number of revertants colonies over the number of spontaneous revertants was considered as a mutagen. Mutagenic-responsive SOS-lux based microbial biosensors were compared to the Ames assay. Mutagenicity assessment of a broad range of environmental pollutants (i.e. B[a]P, DiB(a,h)A, B[a]A, Ni and Cu), was performed using four SOS-lux microbial biosensors; E. coli DPD1718, E. coli K12C600, S. aureus pAmiUmuC and S. aureus pAmiRecA. The results substantiated that the four biosensors were unable to be induced by these pollutants. Nevertheless, E. coli DPD1718 and E. coli K12C600 were successfully induced by Mitomycin C (MMC) in a dose response manner. The Ames assay was performed for the above pollutants in the absence and the presence of the metabolic activation S9 mix. The standard plate incorporation assay and a modification protocol for the Ames assay were applied. Results reported from the Ames assay confirmed mutagenicity responses of the tested pollutants except Cu and Ni. MMC was selected and introduced into soil samples as a case study to assess the performance of the developed tool-kit. Soils amended with MMC were extracted by the in vitro human digestion bioassay, and the mutagenicity of the bioaccessible fraction was measured using the Ames assay and the biosensors. A comparison was made between the permissible concentrations of MMC obtained from the developed tool-kit and RISC4 derived concentrations. The four microbial biosensors applied in this study were incapable to detect the mutagenicity of the tested pollutants. On the other hand, the Ames assay was more robust and sensitive to a broad range of environmental pollutants. The in vitro human digestion bioassay enabled the quantification of the human bioaccessible fraction of the tested pollutants. This fraction posed a concern due to its estimation of the doses that would reach the blood circulation and cause harm to human. While the permissible concentration of MMC measured by the developed tool-kit was less than 10 μg MMC/g, the RISC4 model calculated that it should be 40 μg MMC/g. This revealed that, in this situation, risk assessment model was less conservative than empirical study for human health risk assessment. This study enabled the assessment of the permissible concentrations of environmental pollutants that could remain in a soil and pose permissible harm to humans. This approach also enabled a comparison of modelled and empirical data to allow a measure of sensitivity to be judged. There is a need to develop bioassay techniques more able to assess the potency of hydrophobic compounds both in isolation and combination.

Stability Operations have become the most prevalent mission for U.S. forces in the current global security environment. This research explores new methods to assist in determining when it is acceptable to downsize a force in a stability operation. The methodology developed provides insight into this problem by quantifying force protection risk, mission failure risk, and time in the context of the operational threat environment. The Pythagoras Multi-Agent Simulation and Data Farming techniques are used to investigate force-level comparison in a theoretical threat continuum based on a peacekeeping scenario similar to the Bosnian operation. The data from the simulation is to construct simple tools for decision makers. These tools are used collectively to find the balance, according to a commander's priorities, between the conflicting issues of force protection, mission success, and time. Two areas are identified as significant in achieving success in stability operations. They are troop posturing and troop employment. The problem is that they are often overlooked or under emphasized. The result of this research demonstrates that posturing and employment should be considered as factors equal to force size in contributing to the goal of maximizing force presence. In addition, this research provides a vehicle to assist military planners with ways in which a stability force can maximize and maintain near continuous presence, while simultaneously minimizing the risk to the force and adhere to operational timelines. Overall, the important conclusion in the significance of troop posture on force size transitions. As a force is downsized, it is crucial to evaluate how to maintain presence with the smaller force. This is evident by the surprising success achieved by the smallest force in the simulation. It was able to project a greater presence by utilizing small dispersed units, much like the Combined Action Platoons in Vietnam.