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431.
Susana García Herrero Miguel Ángel Mariscal Saldaña Javier García Rodriguez Dale O. Ritzel 《Journal of Safety Research》2012,43(5-6):365-374
IntroductionOccupational stress is a common phenomenon in our society, and generates problems for both workers' health and the functioning of organizations. Over past decades numerous studies have examined occupational stress from the perspective of gender, offering somewhat contradictory results. Some of them found no differences and others indicated that either men or women suffer from greater amounts of occupational stress.MethodThe purpose of this study was to analyze gender differences in stress in situations that involve certain occupational demands. The data used were taken from a random sample population of 11,054 (5,917 men and 5,137 women) from the VI National Survey on Working Conditions (NSWC) which was conducted in Spain in 2007. To carry out this study, a probabilistic model was constructed using Bayesian networks, with the following variables related to task demands: working with tight deadlines, quick work, intellectually demanding work, complicated tasks, repetitive tasks, excessive work, and work demanding high attention levels.ResultsThe results of this study reveal that: the indicators studied significantly increased stress levels; women initially had higher stress levels than men; and when exposed to determined task demands, stress differences between genders tended to increase.Impact on IndustryCompanies need to consider the gender of their workers when assigning tasks in high demand/stress jobs. 相似文献
432.
Tracking the evolution of research in waste recycling science (WRS) can be valuable for environmental agencies, as well as for recycling businesses. Maps of science are visual, easily readable representations of the cognitive structure of a branch of science, a particular area of research or the global spectrum of scientific production. They are generally built upon evidence collected from reliable sources of information, such as patent and scientific publication databases. This study uses the methodology developed by Rafols et al. (2010) to make a "double overlay map" of WRS upon a basemap reflecting the cognitive structure of all journal-published science, for the years 2005 and 2010. The analysis has taken into account the cognitive areas where WRS articles are published and the areas from where it takes its intellectual nourishing, paying special attention to the growing trends of the key areas. Interpretation of results lead to the conclusion that extraction of energy from waste will probably be an important research topic in the future, along with developments in general chemistry and chemical engineering oriented to the recovery of valuable materials from waste. Agricultural and material sciences, together with the combined economics, politics and geography field, are areas with which WRS shows a relevant and ever increasing cognitive relationship. 相似文献
433.
Influence of nutrients in the feeding ecology of seagrass (Posidonia oceanica L.) consumers: a stable isotopes approach 总被引:1,自引:1,他引:0
Nitrogen inputs to coastal environments can considerably alter the abundance of primary producers. However, how herbivores
modify their trophic signatures and adjust to changes in food resource conditions remains controversial. Here, we assess the
effect of nutrient availability on the diet shifts of the two main Mediterranean herbivores, the Sparid fish Sarpa salpa L. and the sea urchin Paracentrotus lividus (Lmk.) that feed mostly on the seagrass Posidonia oceanica L. (Delile), epiphytes and benthic macroalgae. To do this, we (1) investigate the patterns of isotopic composition (δ13C and δ15N signatures) of the two herbivores and their potential food sources in three areas of contrasting nutrient conditions and,
(2) we assess the diet shift along this nutrient gradient by estimating the isotopic nutrient enrichment (i.e., the contribution
of δ13C and δ15N signatures in consumers’ tissues relative to potential food sources). Food web signatures of δ13C were similar among the three study sites, and no patterns of δ13C shift were observed in their diets. In contrast, there was a consistent increase in N contents and δ15N along the nutrient gradient for all primary producers and their consumers. The rate of δ15N enrichment was also clearly distinctive between the two herbivores: in P. lividus it increased by 61% along the nutrient gradient, while in S. salpa it remained constant. Our results suggest that sea urchins behave as facultative omnivores and feed on vegetable or mixed
diets depending on the trophic status of the system. It is unclear, however, if this modification is behavioral or the consequence
of mere changes in the availability of food items, as animal epiphytes (e.g., hydrozoans, bryozoans and ascidians) can also
became more abundant on seagrass leaves under increased nutrient conditions. In contrast, adult fish appear to feed on vegetal
material independent of nutrient availability in the ecosystem. 相似文献
434.
Leonardo A. Venerus Javier E. Ciancio Carla Riva-Rossi Elizabeth A. Gilbert-Horvath Atila E. Gosztonyi John Carlos Garza 《Die Naturwissenschaften》2013,100(7):645-658
Rockfishes of the genus Sebastes are extensively distributed in the Pacific and Atlantic oceans. Although the occurrence of two morphologically similar species in the Southern Hemisphere, Sebastes oculatus and Sebastes capensis, is now clearly established, the taxonomic status and phylogeographic patterns for the genus in the region have not yet been completely resolved. In this study, we provide new insights into the taxonomy and evolutionary relationships of rockfishes inhabiting the Southwestern Atlantic Ocean, off the coast of mainland Argentina, by combining mitochondrial DNA (mtDNA) control region sequences, microsatellite data, and color pattern analyses. Differences in coloration (“dark” and “light” fish) together with bathymetric segregation between color morphotypes were evident from fish collection and literature review. In addition, the mtDNA phylogenetic analysis and Bayesian clustering analysis using microsatellite data separated the fish into two distinct groups (F ST?=?0.041), most likely representing incipient species. Our results suggest that speciation-by-depth in the absence of physical barriers could be a widespread mechanism of speciation in Sebastes from both the Northern and Southern Hemispheres. Nevertheless, the degree of genetic differentiation found, added to the large number of individuals displaying high levels of admixture, points to the occurrence of incomplete reproductive barriers between color morphotypes. Beyond the taxonomic and phylogeographic implications of our findings, the occurrence of distinct groups of Sebastes off the coast of Argentina being targeted by different fisheries (angling and trawling) has consequences for the design and implementation of appropriate fishery regulations to avoid overharvest of either group. 相似文献
435.
Carotenoid pigments cannot be synthesized by vertebrates but must be ingested through the diet. As they seem to be a limited
resource, carotenoid-based ornaments are particularly interesting as possible honest signals of individual quality, in particular
of foraging efficiency and nutritional status. Some studies have demonstrated the condition dependence of carotenoid-based
plumage in birds. However, many other carotenoid-pigmented bare parts (i.e. skin, caruncles, bills, cere, and tarsi) are present
in birds but, in comparison with plumage, little is known about these traits as indicators of individual quality. Here, we
show that the eye ring pigmentation and bill redness of the red-legged partridge (Alectoris rufa) are positively associated to body condition and recent changes in body mass. Also, we found a negative relationship between
these two traits and heterophil-to-lymphocyte ratio, an indicator of physiological stress (the relationship with bill redness
being significant only for males). In an experiment, we found that after a period of reduction in food intake (with the consequent
loss of body mass), food-restricted birds showed lower eye ring pigmentation than ad-libitum-fed birds. Therefore, different
ornaments seem to reflect changes in body condition but at different speeds or intensities (eye ring, a fleshy ornament, appears
to respond more rapidly to changes in the nutritional status than a keratinized structure as the bill). These results indicate
that carotenoid-based ornaments are condition-dependent traits in the red-legged partridge, being therefore susceptible to
be employed as honest signals of quality in sexual selection. 相似文献
436.
RÔMULO ROMEU DA NÓBREGA ALVES GENTIL ALVES PEREIRA FILHO YURI CLÁUDIO CORDEIRO DE LIMA 《Environment, Development and Sustainability》2007,9(4):455-464
This paper documents zootherapeutic practices in Northeast Brazil. It is primarily based on field surveys carried out in fishing villages located in the States of Maranhão and Paraíba, where dwellers provided information on snake species used as medicine, body parts used to prepare the remedies, and the illnesses to which the remedies were prescribed. The species used as medicinal drug and their respective families were: Crotalus durissus (rattlesnake), Bothrops leucurus (‘lance head’, a venomous snake), and Lachesis muta (bushmaster) of the family Crotalidae; and Boa constrictor (boa constrictor), Epicrates cenchria (‘salamanta’), and Eunectes murinus (anaconda) of the family (Boidae). These zootherapeutical resources were used for the cure of 14 illnesses. The most commonly cited species were Crotalus durissus (n=26) e Boa constrictor (n=6), Apparently, the medicinal use of snakes does not pose a threat for their population in the studied sites. 相似文献
437.
438.
439.
del Real Álvaro Expósito Andrea Ruiz-Azcona Laura Santibáñez Miguel Fernández-Olmo Ignacio 《Environmental science and pollution research international》2022,29(42):62973-62983
Environmental Science and Pollution Research - We aimed to determine the presence of SARS-CoV-2 RNA in indoor and outdoor size-segregated aerosol samples (PM10-2.5, PM2.5). Five outdoor daily... 相似文献
440.
Fassiano Anabella Victoria March Hugo Santos Marina Juárez Ángela Beatriz Ríos de Molina María del Carmen 《Environmental science and pollution research international》2022,29(21):31384-31399
Environmental Science and Pollution Research - Imazethapyr, a selective systemic herbicide, is widely used in agriculture and it is frequently detected in water bodies close to application areas.... 相似文献