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991.
Objective: The objective of this study is to identify the role of working conditions as predictors of sleepiness while driving among truck drivers.

Methods: This was a cross-sectional study carried out among truck drivers who transported grains to Paranaguá Port, Paraná, Brazil. The truck drivers were interviewed and completed a self-administered questionnaire to collect data on sociodemographic and behavioral variables, working conditions, consumption of illicit psychoactive substances, and sleep patterns. Drivers were considered to be sleepy while driving if they reported a medium or high probability of napping while driving at night, during the daytime, or while stopped in traffic. The statistical analysis used logistic regression models progressively adjusted for age, behavioral variables, sleep duration, and other working conditions.

Results: In total, 670 male drivers, with a mean age of 41.9 (±11.1) years, were enrolled. The prevalence of sleepiness while driving was 31.5%. After model adjustments, the following working conditions were associated with sleepiness while driving: Distance from the last shipment of more than 1,000?km (odds ratio [OR]?=?1.54; 95% confidence interval [CI], 1.07–2.23) and a formal labor contract with a productivity-based salary (OR = 2.65; 95% CI, 1.86–3.78). Consumption of illicit psychoactive substances (OR = 1.99; 95% CI, 1.14–3.47) was also associated with sleepiness while driving.

Conclusions: Distance traveled and a formal labor contract with productivity-based earnings were the working conditions associated with sleepiness while driving, regardless of other working or behavioral characteristics, age, consumption of illicit psychoactive substances, and sleep duration.  相似文献   
992.
Employees working in the hospitality industry are constantly exposed to occupational stressors that may lead employees into experiencing burnout syndrome. Research addressing the interactive effects of control, community and value congruence to alleviate the impact of workplace demands on experiencing burnout is relatively limited. The present study examined relationships among control, community and value congruence, workplace demands and the three components of burnout. A sample of 418 employees working in a variety of hospitality associations including restaurants and hotels in Spain were recruited. Moderation analyses and linear regressions analyzed the predictive power of control, community and value congruence as moderating variables. Results indicate that control, community and value congruence were successful buffers in the relationships between workplace demands and the burnout dimensions. The present findings offer suggestions for future research on potential moderating variables, as well as implications for reducing burnout among hospitality employees.  相似文献   
993.
Ranking of workplaces with respect to working conditions is very significant for each company. It indicates the positions where employees are most exposed to adverse effects resulting from the working environment, which endangers their health. This article presents the results obtained for 12 different production workplaces in the copper mining and smelting complex RTB Bor – ‘Veliki Krivelj’ open pit, based on six parameters measured regularly which defined the following working environment conditions: air temperature, light, noise, dustiness, chemical hazards and vibrations. The ranking of workplaces has been performed by PROMETHEE/GAIA. Additional optimization of workplaces is done by PROMETHEE V with the given limits related to maximum permitted values for working environment parameters. The obtained results indicate that the most difficult workplace is on the excavation location (excavator operator). This method can be successfully used for solving similar kinds of problems, in order to improve working conditions.  相似文献   
994.
Aichivirus 1 (AiV-1) is an enteric virus with 30 nm in diameter, belonging to the genus Kobuvirus in the Picornaviridae family being a causative agent of gastroenteritis in humans. The transmission is via the fecal-oral route, through person to person contact, recreation in contaminated waters, or through the consumption of contaminated food or water. The aim of this study was to determine the frequency and the molecular characterization of AiV-1 in wastewater from Uruguay. Biweekly collections from March 2011 to February 2012 were performed in the cities of Bella Unión, Salto, Paysandú, and Fray Bentos, northwestern region of Uruguay. A total of 96 samples were collected; viruses were concentrated by ultracentrifugation, and AiV-1 was detected by using a nested PCR with primers directed to a conserved region (3CD junction) of the viral genome. A high frequency of AiV-1 (n = 54) was observed at all the cities analyzed mainly in the colder months of the year. AiV-1 was not evidenced as an appropriate viral fecal indicator since when compared with other previously detected enteric viruses, no correlation was observed. All 13 characterized AiV-1 belonged to the genotype B after the phylogenetic analysis performed with the sequences obtained from the first round PCR amplicon. This study demonstrates that AiV-1 is a frequently detected enteric viruses present in wastewater and excreted by infected persons in the northwestern region of Uruguay.  相似文献   
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996.
997.
Understanding of spatio-temporal patterns of sensitive fish species such as skates (Rajidae) is essential for implementation of conservation measures. With insufficient survey data available for these species in Portuguese Continental waters, this study shows that fishery-dependent data associated with fishers’ knowledge can be used to identify potential Essential Fish Habitats (EFH) for seven skate species. Sites with similar geomorphology were associated with the occurrence of juveniles and/or adults of the same group of species. For example, sites deeper than 100 m with soft sediment include predominantly adults of Raja clavata, and are the habitat for egg deposition of this species. Raja undulata and R. microocellata are the more coastal species, preferring sand or gravel habitats, while coastal areas with rocks and sand seabed are potential nursery areas for R. brachyura, R. montagui and R. clavata. The main output of this study is the identification of preferential fishing sites enclosing potential EFH for some species, associated with egg-laying and nursery grounds. The location of these areas will be considered for future seasonal closures, and studies will be conducted to evaluate the biological and socio-economic impacts of such measures. As in the past, fishermen will collaborate in the process of evaluating those impacts, since they have practical and applied knowledge that is extremely valuable for evaluating the advantages and disadvantages of such closures. In conclusion, this study is a first contribution to the understanding and identification of EFH for skate species, associated with nursery and egg deposition sites, with direct application to management.  相似文献   
998.
Summary

Adsorption of chlorfenvinphos and methidathion from dissolutions on H+, Ca++, Na+ and K+ are studied. In all cases the saturating cation distinctly influenced the Freundlich‐type adsorption, with adsorption decreasing in the following sequence: H+> Ca++> Na+ > K+. Chlorfenvinphos adsorption was slightly greater than methidathion in two clays, and the adsorption extent for them in kaolinite is slower that bentonite.  相似文献   
999.
R Tandlich  B Brezná  K Dercová 《Chemosphere》2001,44(7):1547-1555
The effect of two terpenes, carvone and limonene, on the biodegradation of DELOR 103, a commercial mixture of polychlorinated biphenyls (PCBs), by Pseudomonas stutzeri, an isolate from long-term PCB-contaminated soil, was studied in detail. The addition of both carvone and limonene as potential inducers of the dioxygenase metabolic pathway exerted an enhancing effect on PCB biodegradation when glycerol and xylose were used as carbon sources, whereas no such effect could be determined with biphenyl and glucose as substrates. Promising biodegradation values were determined with xylose as carbon source and carvone as terpene inducer. In this system, 30-70% of the congeners were degraded in the presence of 10 mg l(-1) and 20 mg l(-1) carvone, respectively, irrespective of the used concentration, whereas only 7-37% of individual PCB congeners were eliminated from the system without terpene addition.  相似文献   
1000.
In Portuguese waters, thornback ray Raja clavata spawns mainly between May and January, although females and males in spawning condition are found throughout the year. The maturation process can be divided into three main phases by using information on gonad weight, oviducal gland and uterus width in females and on gonad weight, clasper length and sperm duct width in males. Females attain length-at-first-maturity at 784 mm and males at 676 mm, at ages of 7.5 and 5.8 years, respectively. In females larger than length-at-first-maturity, a resting stage was identified characterized by low gonadosomatic index and well-developed oviducal glands and uteri. These results along with the low proportion of adult females that are effectively reproducing per month demonstrated that the thornback ray cannot be considered a continuous spawner as described in other studies. Fecundity was determinate with about 35 eggs released per batch. During the spawning season, a total of four batch episodes occur indicating that the total fecundity was approximately 136 eggs per female. Regional differences may exist in the reproductive strategy of the species, namely on the duration of the spawning season, length-at-first-maturity, and fecundity, which can be related to a more intense fishing pressure in northern European waters.  相似文献   
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