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211.
Environmental issues have been at the center of society's concerns for a long time. Recently, this kind of concern is growing even more due to the damage caused to the environment by electrical and electronic product waste. Based on this same concern, this work aimed to analyze, through a literature review, the production and treatment of electronic waste in today's world, with an emphasis on Brazil and China. The articles reviewed point to an increase in the production of this type of waste, in both Brazil and China, and reveal that the current processes of treatment of electronic waste mostly aim to obtain profit through the recovery of precious metals such as copper. This paper concluded that although Brazil is one of the major producers of e‐waste, more than 90% of its e‐waste has not had a proper final destination. This deficiency in e‐waste treatment in Brazil is mainly due to financial factors and the lack of a robust educational policy focused on the environment. Thus, this work suggests the implementation of an effective educational policy aimed at environmental conservation, as well as investments in research on recycling methods in Brazil, especially on the use of e‐waste as an aggregate in the manufacture of concrete.  相似文献   
212.
Environmental Management - Water level variation has an important role in the biology of fish species, driving behavior, feeding, and reproduction both in natural and modified environments. In...  相似文献   
213.
We present a decision support framework for science-based assessment and multi-stakeholder deliberation. The framework consists of two parts: a DPSIR (Drivers–Pressures–States–Impacts–Responses) analysis to identify the important causal relationships among anthropogenic environmental stressors, processes, and outcomes; and a Decision Landscape analysis to depict the legal, social, and institutional dimensions of environmental decisions. The Decision Landscape incorporates interactions among government agencies, regulated businesses, non-government organizations, and other stakeholders. It also identifies where scientific information regarding environmental processes is collected and transmitted to improve knowledge about elements of the DPSIR and to improve the scientific basis for decisions. Our application of the decision support framework to coral reef protection and restoration in the Florida Keys focusing on anthropogenic stressors, such as wastewater, proved to be successful and offered several insights. Using information from a management plan, it was possible to capture the current state of the science with a DPSIR analysis as well as important decision options, decision makers and applicable laws with a the Decision Landscape analysis. A structured elicitation of values and beliefs conducted at a coral reef management workshop held in Key West, Florida provided a diversity of opinion and also indicated a prioritization of several environmental stressors affecting coral reef health. The integrated DPSIR/Decision landscape framework for the Florida Keys developed based on the elicited opinion and the DPSIR analysis can be used to inform management decisions, to reveal the role that further scientific information and research might play to populate the framework, and to facilitate better-informed agreement among participants.  相似文献   
214.
Forest fires represent a serious threat to public security in Europe due to the large burned area. Moreover, smoke pollution due to forest fire events is an important public health issue for the communities directly affected, and particularly for the personnel involved in firefighting operations. Aiming to contribute to the scientific knowledge concerning firefighters exposure to forest fires smoke, data of individual exposure to carbon monoxide, nitrogen dioxide, volatile organic compounds, and particulate matter were obtained during experimental field fires for a group of 10 firefighters equipped with portable “in continuum” measuring devices. Measured values are very high exceeding the Occupational Exposure Standard limits, in particular for peak limit thresholds. These are the first measurements and analysis of firefighter's individual exposure to toxic gases and particles in fire smoke experiments in Europe. However, they already indicate that urgent measures to avoid these levels of exposure are needed.  相似文献   
215.
Collection of municipal solid waste (MSW) may account for more than 70% of the total waste management budget, most of which is for fuel costs. It is therefore crucial to optimise the routing network used for waste collection and transportation. This paper proposes the use of geographical information systems (GIS) 3D route modelling software for waste collection and transportation, which adds one more degree of freedom to the system and allows driving routes to be optimised for minimum fuel consumption. The model takes into account the effects of road inclination and vehicle weight. It is applied to two different cases: routing waste collection vehicles in the city of Praia, the capital of Cape Verde, and routing the transport of waste from different municipalities of Santiago Island to an incineration plant. For the Praia city region, the 3D model that minimised fuel consumption yielded cost savings of 8% as compared with an approach that simply calculated the shortest 3D route. Remarkably, this was true despite the fact that the GIS-recommended fuel reduction route was actually 1.8% longer than the shortest possible travel distance. For the Santiago Island case, the difference was even more significant: a 12% fuel reduction for a similar total travel distance. These figures indicate the importance of considering both the relief of the terrain and fuel consumption in selecting a suitable cost function to optimise vehicle routing.  相似文献   
216.
Because agonistic behaviour can increase an individual's risk of predation, natural selection should favour individuals that modify their behaviour in the face of predation hazard in ways that maximise fitness. We investigated experimentally the effects of an increase in the apparent risk of predation on male-male competition within mixed-sex shoals of the Trinidadian guppy (Poecilia reticulata). We show that males engaged in significantly fewer aggressive interactions with conspecific males in the presence of a fish predator. However, they continued to court and attempt copulations with females at the same rate irrespective of the level of predation risk. In comparison, under predation hazard, female guppies were less responsive sexually and avoided fewer male copulation attempts. Such predator-mediated changes in male-male agonistic interactions and female sexual responsiveness towards males have important implications for the mode and intensity of sexual selection within populations.  相似文献   
217.
The water reservoir of Vargem das Flores, Brazil, has been subject to eutrophication problems. The occurrence of cyanobacterial blooms in this water body has raised concerns regarding the presence of toxic metabolites. In order to understand the factors that promote the proliferation and distribution of cyanobacteria in the reservoir, physicochemical parameters, species composition, and toxicity of the reservoir water column were analyzed at monthly intervals over a 3-year period (2004-2007) using a range of analytical techniques. The results showed that cyanobacteria were absent in the dry period, returning after the onset of stratification. A succession pattern was observed within this group. The Aphanocapsa genus was dominant in the last rainy period of the study (October 2006 to March 2007). However toxicity was only detected when the genera Microcystis and Sphaerocavum were present (October 2005). The principal components analysis showed negative correlation between cyanobacteria and orthophosphate. The change of dominant cyanobacteria along the 3 years of study and the final prevalence of nontoxic genera in the reservoir is an evidence of water quality improvement in response to the management techniques implemented in the reservoir basin.  相似文献   
218.
Despite the classification as known or suspected human carcinogens, by the International Agency for Research on Cancer, the antineoplastic drugs are extensively used in cancer treatment due to their specificity and efficacy. As human carcinogens, these drugs represent a serious threat to the healthcare workers involved in their preparation and administration. This work aims to contribute to better characterize the occupational exposure of healthcare professionals to antineoplastic drugs, by assessing workplace surfaces contamination of pharmacy and administration units of two Portuguese hospitals. Surface contamination was assessed by the determination of cyclophosphamide, 5-fluorouracil, and paclitaxel. These three drugs were used as surrogate markers for surfaces contamination by cytotoxic drugs. Wipe samples were taken and analyzed by HPLC-DAD. From the total of 327 analyzed samples, in 121 (37 %) was possible to detect and quantify at least one drug. Additionally, 28 samples (8.6 %) indicate contamination by more than one antineoplastic drug, mainly in the administration unit, in both hospitals. Considering the findings in both hospitals, specific measures should be taken, particularly those related with the promotion of good practices and safety procedures and also routine monitoring of surfaces contamination in order to guarantee the appliance of safety measures.  相似文献   
219.
Gill anomalies in two fish species (Geophagus brasiliensis and Astyanax bimaculatus) were compared among three freshwater systems with different water quality: one eutrophic river, one eutrophic reservoir, and one oligotrophic reservoir. The raised hypotheses are that reservoirs with low water quality (eutrophic) have fish with more gills anomalies compared with reservoirs with high water quality (oligotrophic), and that the more stable environmental conditions of eutrophic rivers have fish with better healthy conditions than eutrophic reservoirs that have lesser stable environmental conditions. Gills of 36 adult individuals of G. brasiliensis and 23 of A. bimaculatus collected during the winter 2008 and winter 2009 were examined, and the proportions of occurrence of nine histological alterations were compared for the two species among the three systems using a binomial t test for independent samples. Histological changes in fish gills that are reversible and unspecific, such as epithelial lifting, interstitial edema, leukocyte infiltration, hyperplasia of the epithelial cells, lamellar fusion, and vasodilatation were common in both fish species in the three systems. However, lamellar aneurism, which is a more serious and often irreversible anomaly, and lamellar blood congestion occurred only in fish from the two reservoirs. Alternatively, necrosis occurred more in fish from the river. Fish gill anomalies in both species did not differ between the two reservoirs, despite having different water quality. We rejected the hypothesis that reservoirs with lower water quality have fish with more gill injuries compared with high water quality reservoirs. Moreover, the eutrophic river seems to affect differently the healthy condition of fish species, compared with the eutrophic reservoir.  相似文献   
220.
For many millennia humans and reptiles have interacted, but the attitude of humans towards these animals has depended on culture, environment, and personal experience. At least 719 reptile species are known to occur in Brazil and about 11% of this fauna has been exploited for many different purposes, including bushmeat, leather, ornamental and magic/religious uses, and as folk medicines. Brazil can therefore serve as an interesting case study for better understanding reptile use by human societies, and the present paper catalogues some of the reptile species being used in Brazil and discusses implications for their conservation. A literature review indicated that 81 reptile species are culturally important in this country, with 47 (58%) species having multiple uses, 54 being used for medicinal purposes, 38 as food, 28 for ornamental or decorative purposes, 20 used in magic/religious practices, 18 as pets, and 40 are commonly killed when they come into contact with humans. Regarding their conservation status, 30 (37.5%) are included on State's Red List, Brazilian Red List or the IUCN Red List. There are many forms of interaction between reptiles and humans in Brazil-although most of them are quite negative in terms of wildlife conservation-which reinforces the importance of understanding such uses and interactions in the context of protecting reptiles in Brazil. A better understanding of the cultural, social, and traditional roles of these reptiles is fundamental to establishing management plans for their sustainable use.  相似文献   
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