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101.
The objective of this study was to identify Z. indianus in PEJC and PESCAN. Listed are the following methods: to isolate bacteria from the integument of the Z. indianus species collected and to check the resistance of microorganisms to antibiotics. Collections of Z. indianus were performed in four seasons of the two parks. The results obtained suggest that the low amount of Z. indianus collected can be justified by environmental factors such as high average temperature and low average humidity. It is noted that there is a predominance of bacteria of the Enterobacteriaceae family found in both the PEJC and the PESCAN. The antibiogram performed for the isolated PEJC bacteria shows statistical significance when comparing the edge and inside values of the park. Studies with fungi were also carried out, and it was evidenced that Trichophyton spp. was the genus that most inhabited the two environments studied. The ability of fluconazole and ketoconazole to inhibit fungal growth was also investigated, and considering the concentration tested may suggest that they have good action spectra. Plasmid profile data show that 60% of antibiotic-resistant bacteria have plasmids. The values found show that Z. indianus can act as vectors of microorganisms that affect the healthy animals and humans and that these organisms may be influenced by seasons.  相似文献   
102.
Surface water quality monitoring networks are usually deployed and rarely re-evaluated with regard to their effectiveness. In this sense, this work sought to evaluate and to guide optimization projects for the water quality monitoring network of the Velhas river basin, using multivariate statistical methods. The cluster, principal components, and factorial analyses, associated with non-parametric tests and the analysis of violation to the standards set recommended by legislation, identified the most relevant water quality parameters and monitoring sites, and evaluated the sampling frequency. Thermotolerant coliforms, total arsenic, and total phosphorus were considered the most relevant parameters for characterization of water quality in the river basin. The monitoring sites BV156, BV141, BV142, BV150, BV137, and BV153 were considered priorities for maintenance of the network. The multivariate statistical analysis showed the importance of a monthly sampling frequency, specifically the parameters considered most important.  相似文献   
103.
Production of rice husks in Rio Grande do Sul State, which is the major rice production state in Brazil, needs to be adequately managed to diminish environmental impacts. A Micro Thermal Power Plant (MTP), which is a compact and small-scale biomass thermal power plant technology, can be used in electricity generation in thermal power plants with a power capacity up to 800 kWel. This paper presents a feasibility analysis of a 300 kWel MTP that is fuelled by rice husks using two different scenarios: the autoproduction (Case 1) and the independent production (Case 2) of electricity. Both scenarios were found to be unfeasible. Therefore, a sensitivity analysis is performed to evaluate the variables that affect feasibility, such as the electricity commercialization price, the value of certified emission reductions and the financial interest rates. According to sensitivity analysis, small-scale thermal power plants could have feasibility if they received incentives through government programmes, such as through the exemption of equipment taxes and/or the reduction or elimination of the financial interest rate.  相似文献   
104.
Biological monitoring through animals exposed to pollutants using biomarkers provides a promising tool for the identification of pollutants that may cause damage to human health and/or to sustainability of ecosystems. The effects of pollutants in fish tissues are important tools to understand the impact of human activities in natural ecosystems. The aim of this work was to study the water quality of two estuarine lakes in Santa Catarina, Brazil (Camacho Lake and Santa Marta Lake). Geophagus brasiliensis is a species widely distributed in Brazil and was used in this work. Comet assays in peripheral red blood and kidney cells, micronucleus tests in peripheral red blood cells, measurements of acetylcholinesterase activity in axial muscle and histopathological analysis of liver were used as biomarkers. Three sampling campaigns were undertaken in November 2004, June 2005 and November 2005. Thirty adult animals were sampled from each of three different sites (P1—Santa Marta Lake, P2 and P3—Camacho Lake). A negative control was sampled in a non-polluted site at Costa Ecological Park, Paraná. The positive control for genotoxicity was obtained by treating animals with copper sulphate. The results showed that both studied lakes are impacted by potential genotoxic substances. Severe lesions in liver of G. brasiliensis were also observed. The inhibition of acetylcholinesterase activity suggests the presence of pesticides or metals in the studied sites. This work shows that the water quality of Santa Marta and Camacho Lakes have been compromised and further control source of pollutants into these ecosystems is required.  相似文献   
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106.
Nuclear power plants release 14C during routine operation mainly as airborne gaseous effluents. Because of the long half-life (5730 years) and biological importance of this radionuclide (it is incorporated in plant tissue by photosynthesis), several countries have monitoring programs in order to quantify and control these emissions. This paper compares the activity of 14C in soils taken within 1 km from a Brazilian nuclear power plant with soils taken within a reference area located 50 km away from the reactor site. Analyses of total carbon, δ13C and 137Cs were also performed in order to understand the local soil dynamics. Except for one of the profiles, the isotopic composition of soil organic carbon reflected the actual forest vegetation present in both areas. The 137Cs data show that the soils from the base of hills are probably allocthonous.  相似文献   
107.
Journal of Material Cycles and Waste Management - A discussion is currently under way in the literature on the sustainable benefits of recycling material, particularly paper, which has high global...  相似文献   
108.
109.
Objectives. The purpose of this study is to evaluate the influence of the work surface and task difficulty on the head, upper back and upper arm postures and activity of the descending trapezius during a simulated mouse task. Methods. Healthy female university students (N?=?15) were evaluated. The work surface was positioned at elbow height (EH) and above elbow height (AEH) and the task difficulty was set at low (LD) and high (HD) levels. The postures were recorded by inclinometers. Trapezius activity was normalized by the maximum voluntary isometric contraction (MVIC). Results. Significantly higher head flexion was found at EH compared to the AEH condition, with an average difference of 2°–5° at the same difficulty level. The HD task significantly increased head (3°–6°) and upper back flexion (6°–7°) at the same table height. For upper arm elevation and trapezius activation, the AEH condition presented higher upper arm elevation (about 6°–8°) and trapezius activity (0.8–1.4% of MVIC), regardless of the difficulty level of the task. Conclusions. Head posture was influenced by the table height and task difficulty; the upper back posture by high difficulty; and upper arm posture and trapezius activity were only influenced by table height.  相似文献   
110.
Ferreira PD  Castro Pde T 《Ambio》2005,34(3):212-217
The giant Amazon river turtle (Podocnemis expansa) nests on extensive sand bars on the margins and interior of the channel during the dry season. The high concentration of nests in specific points of certain beaches indicates that the selection of nest placement is not random but is related to some geological aspects, such as bar margin inclination and presence of a high, sandy platform. The presence of access channels to high platform points or ramp morphology are decisive factors in the choice of nesting areas. The eroded and escarped margins of the beaches hinder the Amazon river turtle arriving at the most suitable places for nesting. Through the years, changes in beach morphology can alter nest distribution.  相似文献   
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