Protective clothing ensembles are worn by workers as a barrier to chemical and physical hazards, but can restrict heat loss and increase worker heat stress. The question of whether a respirator adds to heat stress or strain burden is a continuing concern among occupational health professionals. The purpose of this study was to determine if there are differences in heat stress or strain among the current Toxicological Agent Protective (TAP) ensemble and two ensemble variations used in demilitarization of chemical weapons. Four acclimatized adult males wore five ensembles in a balanced design while walking in a climatic chamber at a metabolic rate of about 170 W m-2. Heat stress (critical wet bulb globe temperature-WBGTcrit, evaporative resistance-Re,T,a, Clothing Adjustment Factor [CAF]) and heat strain (physiological strain index [PSI]) were compared against work clothes (WC) without respirator (a baseline ensemble); the current TAP apron over cloth coveralls with respirator (TAP+CA); the current TAP apron over cloth coveralls with respirator plus Tychem F® chemical barrier pants (TAP+CA+P); and Tychem F® Coveralls over cloth coveralls with respirator (VB+CA). A no-respirator comparison with the Tychem F coveralls (VB+CA-noR) was added to evaluate the contribution of a full-face negative pressure air-purifying respirator to heat stress. A progressive heat stress protocol was used to determine WBGTcrit, Re,T,a, CAF, and PSI. The results (WBGTcrit [°C-WBGT], Re,T,a [kPa m2 W-1], and PSI) were WC (35.5, 0.0112, 2.0), TAP (31.6, 0.0175, 1.8), TAP+P (27.7, 0.0240, 1.9), VB+CA (25.9, 0.0287, 1.8), and VB+CA-noR (26.2, 0.0293, 1.8). Mixed effects ANOVA was used to assess ensemble effects. Tukey's test was used to determine where significant differences occurred. WBGTcrit was the WBGT at the upper limit of thermal balance. Re,T,a increased while WBGTcrit progressively decreased going from WC to TAP+CA to TAP+CA+P to VB+CA. WBGTcrit was different between Work Clothes and TAP+CA and between WC and TAP+CA and the other ensembles. Re,T,a was different among all ensembles, except no differences in WBGTcrit and Re,T,a were observed between the presence and absence of a respirator with VB+CA. There were no differences among all ensembles for rectal temperature, heart rate, and PSI. Based on both WBGTcrit and Re,T,a, there were significant increases in heat stress going from WC to TAP+CA to TAP+CA+P to VB+CA. No differences in WBGTcrit, Re,T,a, and PSI were found for the presence or absence of a respirator, indicating no additional heat stress or strain burden. CAF is the WC WBGTcrit minus the ensemble WBGTcrit.. The recommended clothing adjustment factors (CAFs) are 0°C-WBGT for WC, 4 °C-WBGT for TAP+CA, 8 °C-WBGT for TAP+CA+P and 10 °C-WBGT for VB+CA. As vapor-barrier ensembles are sensitive to humidity, adding 2 °C-WBGT to VA+CA for a CAF of 12 °C-WBGT is recommended. This implicates the type of protective clothing ensemble worn will play a much bigger role in workplace heat stress effects and risk than the wear of a respirator.

This cumulative dissertation includes four peer-reviewed and published articles. It evaluates three open-access radar quantitative precipitation estimate (QPE) products from the German Weather Service (DWD) with different temporal resolutions. The improved length and quality of the DWD’s radar QPE products allows a detailed assessment of existing statistical precipitation characteristics and scaling laws, which are established on the basis of traditional point measurements only. The focus of the thesis is on heavy to extreme rainfall and scaling characteristics in time and space. The first publication is a comprehensive assessment of spatio-temporal heavy rainfall pattern in context of urban rainfall modification. The analysis identifies storm alteration by the city of Berlin using the RADOLAN-RW product, suitable for event analysis. Six storm categories were identified and newly introduced tools, such as the amplification factor helped to quantify the changes. The second and third publications focus on the re-evaluation of point-based findings from literature. The first compares depth-duration relationships based on 400,000+ grid cells within Germany for durations of 10 min to 3 days based on 16 years of RADKLIM-YW (5 min and 1 km spatio-temporal resolution) with a well-established global rainfall maxima curve. The German regional curve showed a 'three-phase-regime', governed by the temporal structure of very few extreme rainfall events. Three groups of curve characteristics for single grid cells were identified, based on the rainstorms that had occurred at the individual location. The third article shows the significance of using moving time interval maxima (M-Maxima) over fixed maxima (F-Maxima) and also helps to describe the probabilistic nature of the distribution of potential correction factors, in this case the Sampling Adjustment Factor (SAF), more accurately. It uses both RADKLIM products in order to compare different base resolutions and its effects on the results. Findings add new insights into the importance of identifying good correction factors and also consider the distribution of them instead of using average factors as usually done in practice. The fourth publication studies a new method to extrapolate extreme rainfall to sub-pixel scale via a simple scaling approach, based on 19 years of RADKLIM-RW (hourly and 1 km spatio-temporal resolution) and four regions within Germany of each 256 km x 256 km. Almost smooth power laws were observed when looking at the depth-area-relationships, depending on the considered data length and regions. Closer to the resolution of the radar data (1x1 km²), other influencing factors lead to a shift in rainfall characteristics and thus a bend of the relationship. The two rainfall classes of more convective and more advective characteristics generally had a strong influence on all results of the thesis and are highly dependent on the temporal resolution of the data. The gridded radar QPE data helped to reveal characteristics such as the correlation of small areas with high rain rates (connected to convective pattern) and larger areas with lower rain rates (connected to advective pattern). The analysed radar QPE products are suitable for analysing spatial and temporal rainfall pattern. However, for extreme values, uncertainty remains, since it is not clear if very extreme values are outliers or 'true' observations. / Diese kumulative Dissertation umfasst vier begutachtete und veröffentlichte Artikel. Sie wertet drei frei zugängliche Radarkomposite (QPE) des Deutschen Wetterdienstes (DWD) mit unterschiedlichen zeitlichen Auflösungen aus. Die verbesserte Länge und Qualität dieser Produkte ermöglicht eine detaillierte Bewertung vorhandener Niederschlagscharakteristika, die auf Punktmessungen beruhen. Der Schwerpunkt der Arbeit liegt dabei auf Stark- bis Extremniederschlägen und deren Skalierungseigenschaften. Die erste Veröffentlichung ist eine umfassende Bewertung der raum-zeitlichen Starkregenmuster im Kontext der städtischen Niederschlagsmodifikation. Die Analyse identifiziert den Einfluss der Stadt Berlins auf Starkregenereignisse unter Verwendung des RADOLAN-RW-Produkts. Sechs Kategorien von Niederschlagsmodifikationen wurden identifiziert und neu eingeführte Werkzeuge, wie der Verstärkungsfaktor, halfen bei der Quantifizierung der Veränderungen. Die zweite und dritte Publikationen konzentrieren sich auf die Neubewertung von punktbasierten Erkenntnissen aus der Literatur. Erstere vergleicht Niederschlags-Dauer-Beziehungen auf der Basis von mehr als 400.000 Rasterzellen innerhalb Deutschlands für Dauern von 10 min bis 3 Tagen auf der Grundlage von 16 Jahren RADKLIM-YW (5 min und 1 km räumlich-zeitliche Auflösung) mit einer bekannten globalen Niederschlagsmaximumkurve. Die regionale Kurve in Deutschland zeigte ein 'Drei-Phasen-Regime', das durch die zeitliche Struktur von sehr wenigen extremen Niederschlagsereignissen bestimmt wird. Es wurden drei Gruppen von Kurvencharakteristika für einzelne Gitterzellen identifiziert, die auf den am jeweiligen Standort aufgetretenen Regenfällen basieren. Zweitere zeigt die Bedeutung der Verwendung von gleitenden (M-Maxima) gegenüber festen Niederschlagsmaxima (F-Maxima) und hilft dabei, die probabilistische Natur der Verteilung potenzieller Korrekturfaktoren, in unserem Fall des 'Sampling Adjustment Factor' (SAF), genauer zu beschreiben. Es wurden beide RADKLIM-Produkte verwendet, um verschiedene Basisauflösungen und ihre Auswirkungen auf die Ergebnisse zu vergleichen. Die Ergebnisse liefern neue Erkenntnisse darüber, wie wichtig es ist, gute Korrekturfaktoren zu ermitteln und auch deren Verteilung zu berücksichtigen, anstatt wie in der Praxis üblich Durchschnittsfaktoren zu verwenden. Die vierte Veröffentlichung untersucht eine neue Methode zur Extrapolation extremer Niederschläge mittels eines einfachen Skalierungsansatzes, basierend auf 19 Jahren RADKLIM-RW (stündliche und 1 km räumlich-zeitliche Auflösung) und vier Regionen in Deutschland mit jeweils 256 km x 256 km. Es wurden nahezu perfekte Potenzgesetze in der Beziehung von Niederschlag und Fläche beobachtet, abhängig von der betrachteten Datenlänge und den Regionen. Nahe an der Auflösung des Radars (1x1 km²) knicken die Beziehungen ab, was auf eine Veränderung der Niederschlagscharakteristika hinweist. Die beiden Niederschlagsklassen mit eher konvektiven und eher advektiven Eigenschaften hatten generell einen starken Einfluss auf alle Ergebnisse der Arbeit und sind stark von der zeitlichen Auflösung der Daten abhängig. Die Radarkomposite halfen dabei, Merkmale wie die Korrelation von kleinen Gebieten mit hohen Niederschlagsmengen (verbunden mit konvektiven Mustern) und größeren Gebieten mit niedrigeren Niederschlagsmengen (verbunden mit advektiven Mustern) aufzuzeigen. Die analysierten Radarkomposite sind für die Analyse räumlicher und zeitlicher Niederschlagsmuster geeignet. Bei Extremwerten bleibt jedoch eine gewisse Unsicherheit, da nicht klar ist, ob es sich bei sehr extremen Werten um Ausreißer oder 'echte' Beobachtungen handelt.

The primary objective of this study is to evaluate the operational effects of U-turn movement at signalized intersections. More specifically, the research objectives include the following parts: To identify the factors affecting the operational performance of U-turning vehicles. In this case, we are particularly interested in the U-turn speeds of U-turning vehicles. To evaluate the impacts of U-turns on capacity of signalized intersections, and To simulate U-turn movement at signalized intersections using Synchro and validate the simulation results. To achieve the research objectives, extensive field data collection work was conducted at sixteen selected sites at Tampa Bay area of Florida. The data collected in the field include: U-turning speed Left turning speed Turning radius Queue discharge time Control delay Hourly traffic volume, and Percentage of U- turning vehicles in left turn lane. Based on the collected field data, a linear regression model was developed to identify the factors affecting the turning speeds of U-turning vehicles at signalized intersections. The model shows the turning speed is significantly impacted by the turning radius and the speed of U-turning vehicles increases with the increase of turning radius. On the basis of field data field data collection, a regression model was developed to estimate the relationship between the average queue discharge time for each turning vehicle and the various percentages of U-turning vehicles in the left turn traffic stream. Adjustment factors for various percentages of U-turning vehicles were also developed by using the regression model. The adjustment factors developed in this study can be directly used to estimate the capacity reduction due to the presence of various percentages of U-turning vehicles at a signalized intersection. The developed adjustment factors were used to improve the simulation of U-turn movement at signalized intersection by using Synchro. The simulation model was calibrated and validated by field data. It was found that using the developed adjustment factors will greatly improve the accuracy of the simulation results for U-turn movement.

Clothing can influence heat stress depending on the design and its ability to act as a barrier. The progressive heat stress protocol permitted the collection of data to empirically estimate the apparent total evaporative resistance (Re,T,a). Five different clothing ensembles were evaluated, which included work clothes, cotton coveralls, and three limited-use protective clothing ensembles including a pthesis-barrier ensemble, (Tyvek® 1424), water-barrier, vapor-permeable ensemble (NexGen® LS 417), and a vapor-barrier ensemble (Tychem QC®). The study design called for three metabolic level's: low, moderate, and high (L, M, & H) and three heat stages: compensable, transitional, uncompensable (C, T, U). The purpose of this study was to determine if Re,T,a values remained constant over a range of metabolic and heat stage levels. Calculated Re,T,a values were compared using a four-way mixed model analysis of variance. Significant differences for Re,T,a were found among ensembles, metabolic levels, heat stress stages, as well as interactions among ensembles and metabolic levels along with ensembles and heat stress stages (p < 0.0001). A Tukey's Honestly Significant Difference multiple comparison test identified where significant differences occurred (p < 0.05). Results show Re,T,a values differ over a range of metabolic levels and stages of heat stress. Additionally, convection is more supportive of evaporative cooling than diffusion.

No description available.

In Florida, the increased installation of non-traversable medians and directional median opening has produced an increased number of U-turns on multilane highways. Arguments have been advanced by some opponents of median modification projects that the increased numbers of U-turns may result in safety and operational problems on multilane highways. The primary objective of this study is to evaluate the operational effects of U-turn movement on multilane roadways. To achieve this research objective, extensive data were collected. Field measurements were conducted at 40 sites in the Tampa Bay area of Florida to collect traffic operations data. Besides, the crash histories of 179 selected roadway segments in central Florida were investigated. Statistical analysis was conducted based on the collected traffic operations data and crash data to quantitatively evaluate the operational performance of U-turn movement. Delay and travel time were compared for different driveway left- turn alternatives that are widely used in Florida and nationally. Crash rate models were developed to evaluate how the separation distance between a driveway exit and the downstream U-turn bay impacts the safety performance of vehicles making right-turns followed by U-turns (RTUT). With the crash data analysis results, the minimum separation distances under different roadway conditions were determined to facilitate driver use of RTUTs. The capacity of U-turn movement was analyzed under two different situations: (1) U-turns are provided at a signalized intersection; and (2) U-turns are provided at an unsignalized intersection. Adjustment factors were developed to quantify the impacts of the presence of U-turning vehicles on the capacity of a signalized intersection. The critical gaps and follow-up time for U-turn movement at unsignalized intersections were estimated. With the estimated critical gaps and follow-up time, the Harders model was used to determine the capacity of U-turn movem ent at an unsignalized intersection. This study also looks extensively at the minimum roadway width and median width required by vehicles to perform U-turn maneuvers on 4-lane divided roadways. It was found that a roadway width of 46 ft is generally sufficient for most types of design vehicles (except heavy vehicles) to perform a continuous U-turn maneuver without impedance.

Made available in DSpace on 2014-12-17T14:23:30Z (GMT). No. of bitstreams: 1 JosivanRJ_DISSERT.pdf: 3858170 bytes, checksum: cf220eba177815a3f2e7efdc0fc51b69 (MD5) Previous issue date: 2013-08-15 / One of the greatest challenges of demography, nowadays, is to obtain estimates of mortality, in a consistent manner, mainly in small areas. The lack of this information, hinders public health actions and leads to impairment of quality of classification of deaths, generating concern on the part of demographers and epidemiologists in obtaining reliable statistics of mortality in the country. In this context, the objective of this work is to obtain estimates of deaths adjustment factors for correction of adult mortality, by States, meso-regions and age groups in the northeastern region, in 2010. The proposal is based on two lines of observation: a demographic one and a statistical one, considering also two areas of coverage in the States of the Northeast region, the meso-regions, as larger areas and counties, as small areas. The methodological principle is to use the General Equation and Balancing demographic method or General Growth Balance to correct the observed deaths, in larger areas (meso-regions) of the states, since they are less prone to breakage of methodological assumptions. In the sequence, it will be applied the statistical empirical Bayesian estimator method, considering as sum of deaths in the meso-regions, the death value corrected by the demographic method, and as reference of observation of smaller area, the observed deaths in small areas (counties). As results of this combination, a smoothing effect on the degree of coverage of deaths is obtained, due to the association with the empirical Bayesian Estimator, and the possibility of evaluating the degree of coverage of deaths by age groups at counties, meso-regions and states levels, with the advantage of estimete adjustment factors, according to the desired level of aggregation. The results grouped by State, point to a significant improvement of the degree of coverage of deaths, according to the combination of the methods with values above 80%. Alagoas (0.88), Bahia (0.90), Cear? (0.90), Maranh?o (0.84), Para?ba (0.88), Pernambuco (0.93), Piau? (0.85), Rio Grande do Norte (0.89) and Sergipe (0.92). Advances in the control of the registry information in the health system, linked to improvements in socioeconomic conditions and urbanization of the counties, in the last decade, provided a better quality of information registry of deaths in small areas / Um dos grandes desafios atuais da demografia ? obter estimativas de mortalidade, de maneira consistente, principalmente em pequenas ?reas. A car?ncia destas informa??es, dificulta a??es de sa?de p?blica e leva ao comprometimento da qualidade de classifica??o de ?bitos, gerando preocupa??o por parte dos dem?grafos e epidemiologistas na obten??o de estat?sticas confi?veis da mortalidade no Pa?s. Neste contexto, o objetivo deste trabalho ? obter estimativas de fatores de ajuste de ?bitos para corre??o da mortalidade adulta, por estados, mesorregi?es e grupos et?rios na regi?o nordeste, em 2010. A proposta est? pautada sobre duas linhas de observa??o: uma demogr?fica e outra estat?stica, considerando tamb?m duas ?reas de abrang?ncia nos estados da regi?o Nordeste, as mesorregi?es como ?reas maiores e os munic?pios como pequenas ?reas. O principio metodol?gico ? usar o m?todo demogr?fico Equa??o Geral e Balanceamento ou General Growth Balance, para corrigir os ?bitos observados, nas ?reas maiores (mesorregi?es) dos estados, por estas serem regi?es menos prop?cias a quebra dos pressupostos metodol?gicos. Em seguida, ser? aplicado o m?todo estat?stico estimador bayesiano emp?rico, considerando como soma dos ?bitos nas mesorregi?es, o valor de ?bito corrigido pelo m?todo demogr?fico e como refer?ncia de observa??o de ?rea menor os ?bitos observados nas pequenas ?reas (munic?pios). Como resultados desta combina??o, um efeito de suaviza??o do grau de cobertura dos ?bitos ? obtido, fruto da associa??o com o estimador bayesiano emp?rico e a possibilidade de avaliar o grau de cobertura de ?bitos por grupos et?rios em n?vel de munic?pios, mesorregi?es e estado, com a vantagem de estimar fatores de ajuste, conforme o n?vel de agrega??o desejado. Os resultados agrupados por estado, apontam para uma melhora significante do grau de cobertura de ?bitos, segundo a combina??o dos m?todos com valores acima de 80%. Alagoas (0,88), Bahia (0,90), Cear? (0,90), Maranh?o (0,84), Para?ba (0,88), Pernambuco (0,93), Piau? (0,85) , Rio Grande do Norte (0,89) e Sergipe (0,92). Os avan?os no controle do registro das informa??es no sistema de sa?de, associado ?s melhorias nas condi??es socioecon?micas e de urbaniza??o dos munic?pios, na ?ltima d?cada, proporcionaram uma melhor qualidade do registro das informa??es de ?bitos nas pequenas ?reas

Ebola, a type of filovirus that causes hemorrhagic fevers, dominated global headlines in 2014 when the largest Ebola epidemic in history took place in West Africa. Healthcare practitioners were at particular risk of contracting Ebola while taking care of patients with the disease because they were easily exposed to bodily fluids such as blood, urine, saliva, and feces, quite often in the intensive care unit (ICU). While personal protective equipment (PPE) protects the healthcare practitioner by providing an effective barrier against the virus, users were also at risk for heat stress because of the type of protective clothing. In this study, coveralls made of monolithic barriers, which prevent water vapor from escaping the suit, were compared to coveralls made of micro- porous material, which allows evaporated sweat to escape the suit. The Microgard® 2000 TS Plus, made of micro-porous barrier material and the monolithic barrier Microgard® 2300 Plus were compared against a control ensemble of work clothes consisting of a long-sleeve shirt and trouser. A progressive heat stress protocol was used to determine the critical environment at the upper limit of compensable heat stress. The critical condition was the point at which the heat gain caused by wearing the protective ensemble as well as dry heat exchange was balanced by the maximum heat loss due to evaporative cooling. Wet bulb globe temperature at the critical condition (WBGTcrit ) ,total evaporative resistance (Re,T,a), and clothing adjustable factor (CAF) were calculated for each ensemble based on data at the critical point. Also at the critical condition, participant rectal temperature vi (Tre) , heart rate (HR), skin temperature (Tsk), and physiological strain index (PSI) were noted and compared for each ensemble. A two-way ANOVA (ensemble x participant) for WBGTcrit and Re,T,a as dependent variables was used to determine whether or not there were differences among ensembles. Tukey’s honest significance test was used to determine where significant differences occurred. WBGTcrit was 33.8, 26.3, and 22.9 °C-WBGT for Work Clothes, M2000, and M2300 respectively. Re,T,a was 0.012, 0.031, and 0.054 kPa m2 W-1 for WC, M2000, and M2300 respectively. The higher the WBGTcrit for an ensemble, the more it can support evaporative cooling and hence the better it is at ameliorating heat stress. Based on this trial, the micro-porous ensemble Microgard® 2000 TS Plus has better heat stress performance than vapor-barrier Microgard® 2300 Plus. As expected, there were no differences for any of the physiological metrics at the critical conditions.

<p dir="ltr"> Improving feed efficiency in beef cattle is essential to meet rising global beef demand while reducing costs and environmental impacts. Genetic selection plays a significant role in identifying and breeding more feed-efficient animals, with multi-population data integration enhancing prediction accuracy. To optimize animals for selection or breeding programs related to efficiency, it is crucial to understand the traits associated with mature cow size and the genetic relationships between them. Mature cow size, defined by mature cow weight (MWT), height (MHT), and body condition score (BCS), is pivotal to cow-calf profitability, maintenance efficiency, and reproductive performance.<br><br> The objectives of the first study were to: 1) estimate variance components and genetic parameters for MWT, MHT, and BCS in the United States (US) and Australia (AUS); 2) estimate genetic correlations between mature cow size traits and early growth and carcass traits; and 3) estimate the genetic correlations among these traits across the two countries. The datasets provided by the American Angus Association and Angus Australia included 434,746 and 206,003 records for MWT, 213,875 and 15,379 records for MHT, and 382,156 and 36,184 records for BCS, respectively. Single-trait repeatability models were used to estimate heritabilities and variance components. Multiple-trait models were used to estimate phenotypic and genetic correlations between traits and across countries. Heritability estimates for MWT (US: 0.45; AUS: 0.40), MHT (US: 0.57; AUS: 0.63), and BCS (US: 0.18; AUS: 0.18) highlighted moderate-to-high genetic control. Genetic correlations within the US and Australian datasets between MWT and MHT, and MWT and BCS were > 0.50, and < 0.20 between MHT and BCS. Genetic correlations between MWT, MHT and early growth traits were generally positive and moderate-to-high, ranging from 0.51(0.01) to 0.92(0.003) in the US and 0.41(0.03) to 0.79(0.05) in Australia. Genetic correlations between the traits in the two countries were high for MWT = 0.91 (0.02) and MHT = 0.98 (0.02); and moderate for BCS = 0.65 (0.08). The results suggested that optimizing selection for mature cow traits is feasible, and that a joint evaluation between the US and Australia could be beneficial. </p><p dir="ltr"><br></p><p dir="ltr"> The objective of the second study was to investigate the impact of different modeling approaches on the estimation of breeding values for MWT, with a focus on how BCS was treated across models. The dataset provided by American Angus Association comprised 382,156 MWT and BCS records from 209,491 cows. Four modeling approaches were evaluated: Model 1 did not consider BCS; Model 2 treated BCS as a categorical fixed effect; Model 3 used pre-adjusted records standardized for BCS and age; and Model 4 used a recursive model to assess MWT as a genetically independent trait from BCS. Spearman correlations between models ranged from 0.78 to 0.95, with model choice influencing sire rankings by 5–22% and top 10% concordance differing by up to 40%. Model selection can significantly affect rankings, highlighting the importance of carefully selecting the model that aligns best with the breeding goals. The recursive approach appears to effectively derive MWT that is genetically independent of BCS. </p><p dir="ltr"> This thesis analyzes genetic relationships among mature cow size traits; mature cow weight, height, and body condition score, providing insights for selection programs aimed at optimizing cow’s efficiency. Through variance analysis and genetic correlation studies across North American and Australian Angus populations, it highlights the potential of joint evaluations across countries. It also assesses how different modeling approaches for estimating breeding values for mature cow weight can affects sire rankings and selection decisions, underscoring the importance of model alignment with breeding objectives. Ultimately, this work contributes to the goal of a more sustainable beef industry, where mature cow size is optimized.</p>