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The effect of exposure time on the percentage of people dissatisfied with draft was studied by exposing subjects to the airflow for 1 h. The results showed that the percentage of subjects dissatisfied with draft increased dramatically in the first 20 min of the exposure, then changed slowly in the last 40 min of the exposure. Based on the experimental results, a model was established to correlate the percentage of dissatisfied due to draft with exposure time as well as airflow velocity, temperature and turbulence intensity. The model is useful to design the air conditioning systems and the layouts of the interior spaces of buildings.

Tobacco-associated carcinogens are catalyzed by microsomal epoxide hydrolase (mEH). Combinations of the Y113H and H139R polymorphic EPHX1 variants have been assumed to alter the enzyme activity and thus the risk of squamous cell head and neck cancer (SCCHN). Based on in vitro data, a putative low, medium and high mEH activity has been associated with combinations of these genotypes, and the respective activity categories have been frequently used in the estimation of risks for smoking-related cancers. We investigated the SCCHN risk for EPHX1 genotypes among 280 cases and 289 controls. We could not detect main effects of the EPHX1 genotypes, but a smaller risk of the 139HR genotype in smokers (odds ratio, OR, 0.57; 95% confidence interval, CI, 0.34-0.95). We could not confirm an increase of the SCCHN risk for genotype combinations according to a putative medium and high enzyme activity (OR 1.28, 95% CI 0.84-1.96; OR 0.98, 95% CI 0.58-1.64, respectively), but a significant heterogeneity of the estimated risks for the singular genotypes within these categories among smokers ( P=0.02). Further, p53 mutations among smoking cases were less frequent in the group with a putative high enzyme activity, although insignificant due to small numbers (OR 0.54, 95% CI 0.13-2.17). This supports uncertainties in categorizing genotypes with respect to limited enzyme activity data, especially when taken from in vitro experiments.

The purpose of this study was to investigate the effect of moisture on the heat transfer through clothing in relation to the water vapour resistance, type of underwear, location of the moisture and climate. This forms part of the work performed for work package 2 of the European Union THERMPROTECT project. Thermal manikin results of dry and wet heat loss are presented from different laboratories for a range of 2-layer clothing with similar dry insulations but different water vapour permeabilities and absorptive properties. The results obtained from the different manikins are generally consistent with one another. For each climate, total wet heat loss is predominately dependent on the permeability of the outer layer. At 10 °C, the apparent evaporative heat loss is markedly higher than expected from evaporation alone (measured at 34 °C), which is attributed to condensation within the clothing and to increased conductivity of the wet clothing layers.Chemicals / CAS: water, 7732-18-5; Water, 7732-18-5

Allelic variations in CYP1B1 are reported to modulate the incidence of several types of cancer. To provide a mechanistic basis for this association, we investigated the impact of nonsilent allelic changes on the intracellular levels and post-translational regulation of CYP1B1 protein. When transiently expressed in COS-1 cells, either in the presence or absence of recombinant cytochrome P450 reductase, the cellular level of the CYP1B1.4 allelic variant (containing a Ser at the amino acid position 453; Ser453) was 2-fold lower compared with the other four allelic CYP1B1 proteins (containing Asn453), as analyzed by both immunoblotting and ethoxyresorufin O-deethylase activity. This difference was caused by post-translational regulation; as in the presence of cycloheximide, the rate of degradation of immunodetectable and enzymatically active CYP1B1.4 was distinctly faster than that of CYP1B1.1. Pulse-chase analysis revealed that the half-life of CYP1B1.4 was a mere 1.6 h compared with 4.8 h for CYP1B1.1. The presence of the proteasome inhibitor MG132 [N-benzoyloxycarbonyl (Z)-Leu-Leuleucinal] increased the stability not only of immunodetectable CYP1B1, but also--unexpectedly given the size of the proteasome access channel--increased the stability of enzymatically active CYP1B1. The data presented herein also demonstrate that CYP1B1 is targeted for its polymorphism-dependent degradation by polyubiquitination but not phosphorylation. Our results importantly provide a mechanism to explain the recently reported lower incidence of endometrial cancer in individuals carrying the CYP1B1*4 compared with the CYP1B1*1 haplo-type. In addition, the mechanistic paradigms revealed herein may explain the strong overexpression of CYP1B1 in tumors compared with nondiseased tissues.

In the context of medical or biological studies, very often parameters of interest are measured repeatedly over time under a given set of conditions. This results in a set of (often similarly shaped) time series. Then, the objective is the determination of the functional relationship between the parameter of interest and time on the one hand, and the analysis of the variation of this functional relationship between experiments, on the other hand. This may be done by means of a two-stage model. The present work describes the theory of the two-stage model and its application to the increase of human core temperature for a set of 678 experiments where the subjects were exposed to warm and hot environments. The data originating from 6 European research institutes, have been pooled into one database for the Heat Stress Project within the scope of the BIOMED 2 programme of the European Union. A nonlinear two-stage model was applied, with a logistic function modelling the nonlinear time course of the core temperature, and with its parameters depending on air temperature, mean radiant temperature, air velocity, partial vapour pressure, clothing insulation, metabolic rate, gender, acclimatisation status and body surface area. We conclude that acclimatisation, clothing insulation, body surface area, air temperature, air velocity, partial vapour pressure, metabolic rate, and the difference between mean radiant temperature and air temperature play an important role for work in warm and hot environments. We show how our results can be used for the estimation of allowable exposure times for work in hot environments.

During the last century about 100 indices were developed to assess influences of the atmosphere on human being. However, most of them have not close relationships with physiological reactions in man. In 1999 International Society of Biometeorology established special study group do develop new Universal Thermal Climate Index (UTCI). Since 2005 these efforts have been reinforced by the COST Action 730 (Cooperation in Science and Technical Development). In February 2009 the Action was terminated and UTCI was developed. The new UTCI index represents air temperature of the reference condition with the same physiological response as the actual condition. The index base on Fiala model that is one of the most advanced multi-node thermophysiological models and include the capability to predict both whole body thermal effects (hypothermia and hyperthermia; heat and cold discomfort), and local effects (facial, hands and feet cooling and frostbite). The model consists of two interacting systems: the controlling active system; and the controlled passive system. The assessment scale of UTCI bases on the intensity of objective physiological reactions to environmental heat stress in wide range of weather and climates. The index can be applicable in various research, for example in weather forecasts, bioclimatological assessments, bioclimatic mapping in all scales (from micro to macro), urban design, engineering of outdoor spaces, consultancy for where to live, outdoor recreation and climatotherapy, epidemiology and climate impact research. The paper presents thermophysiological principles of UTCI as well as some examples of its application to assess bioclimatic differentiation of Europe.