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91.
Environmental Science and Pollution Research - Ciprofloxacin (Cipro) water contamination is a global concern, having reached disturbing concentrations and threatening the aquatic ecosystems. We...  相似文献   
92.
Environmental Science and Pollution Research - The application of sewage sludge (SS) in the soil can be a valuable way to increase its content of organic matter. However, the concentration of...  相似文献   
93.
Environment, Development and Sustainability - In state of Rio de Janeiro, the Southeast Region of Brazil, 97.91% of the reforested areas contain exclusively species of Pinus and Eucalyptus. Due to...  相似文献   
94.
Some health important enteric viruses are considered to be emerging waterborne pathogens and so the improvement of detection of these viruses in the aquatic environment is one of the most important steps in dealing with these pathogens. Since these viruses may be present in low numbers in water, it is necessary to concentrate water samples before viral detection. Although there are several methods to concentrate viruses in environmental waters, all present some drawbacks and consequently the method should be chosen that, despite its limitations, is adequate to achieve the aim of each study. As the effectiveness of the concentration methods is evaluated by determining the efficiency of viral recovery after concentration, it is important to use a simple and effective approach to evaluate their recovery efficiency. In this work ultracentrifugation, usually used as a secondary step for virus concentration, was evaluated as the main method to concentrate directly viruses in environmental water samples, using the microscopic enumeration of virus-like particles (VLP) as a new approach to estimate the efficiency of recovery. As the flocculation method is currently employed to concentrate viruses in environmental waters, it was also used in this study to assess the efficiency of the ultracentrifugation as the main viral concentration method in environmental waters. The results of this study indicate that ultracentrifugation is an adequate approach to concentrate viruses directly from environmental waters (recovery percentages between 66 and 72% in wastewaters and between 66 and 76% in recreational waters) and that the determination of VLP by epifluorescence microscopy is a simple, fast and cheap alternative approach to determine the recovery efficiency of the viral concentration methods.  相似文献   
95.
A majority of the native medicinal plants that are commercialized in Brazil are harvested from natural populations. In addition to this essentially unrestrained collecting, these plants have been heavily impacted by the cutting and the fragmentation of forest formations throughout the country. Considering the limited availability of natural resources, threats to species diversity, and the necessity of conservation efforts in light of the rapid exhaustion of natural ecosystems, it is becoming exceedingly important to establish conservation priorities. The present work sought to identify the native medicinal plants harvested for industrial purposes and to establish conservation priorities for the species of highest commercial value. To that end, a survey of Brazilian industrial products that use medicinal plants was undertaken in 54 shops in the city of Recife (Pernambuco, NE Brazil). The survey noted information concerning the commercial name of the product, its plant composition and pharmaceutical presentation, therapeutic indications, as well as the laboratory that produced it. Only native species were considered. A total of 74 different native species used to produce more than 300 types of products were encountered in the present survey. Twelve species demonstrated significant versatility (Species which had the highest numbers of different therapeutic indications and body systems), and 58.33% of these plants were trees. Destructive collecting predominates (58.11%), greatly affecting taxa collected exclusively from wild populations (86.49%). The intensive use of exclusively wild species and the destructive harvesting techniques employed in gathering them create serious problems that will threaten the availability of these resources to future generations.  相似文献   
96.
Environmental Monitoring and Assessment - Due to the concern with the quality of hydric resources, the monitoring is essential to evaluate and identify the anthropogenic and environmental...  相似文献   
97.
Ribeira Bay is located approximately 130 km south of the city of Rio de Janeiro and receives discharges of liquid effluent from the Angra dos Reis nuclear power plant (NPP) site, where two pressurized water reactors are located. To test whether the presence of anthropogenic radionuclides in sediments in Ribeira Bay could be correlated to the NPP operations, we sampled seven sediment cores and determined accumulation rates and chronologies. Only one sediment core did not exhibit a superficial mixing layer; this sample was used for dating purposes. Cesium-137 and 207Bi were observed in this sediment profile, but their presence was associated with atmospheric fall-out rather than the nearby NPP. The exponential decay of 210Pb concentration with sediment layer depth was verified below a superficial mixing layer for all other sediment cores. Calculated accumulation rates ranged from 1.2 mm y−1 in the inner bay to 6.2 mm y−1 close to its entrance.  相似文献   
98.
Atmospheric air samples were taken within 3 km from power plants encompassing five different distances and wind directions. Samples were taken between 2002 and 2005 aiming to evaluate the environmental 14C enrichment due to the operation of Brazilian nuclear power plants. The sampling system consisted of a pump connected to a trapping column filled with a 3 M NaOH solution. The trapped CO2 was analyzed for 14C by using a single stage accelerator mass spectrometry (SSAMS).  相似文献   
99.
In the 35 years since its inception, the Brazilian National Program for the Conservation of Marine Turtles (TAMAR) has had great success in protecting the five species of sea turtles that occur in Brazil. It has also contributed significantly to worldwide scientific data and knowledge about these species’ biology, such as life cycles and migration patterns. TAMAR’s conservation strategies have always relied on a variety of environmental education and social inclusion (EESI) activities highly adapted to the socio-environmental evolving contexts of its 25 locations distributed across nine states. Diversity and flexibility are critical to enable timely and effective local responses to existing or potential threats to sea turtles. The intuitive, locally adapted, decentralized, and independent way EESI activities have been carried out have generated positive results in the resolution of specific and evolving local problems through the course of the project. This article brings EESI under the same conceptual framework that underlies its conservation approach by adopting an adaptive threat management framework to organize and qualify its educational and social inclusion interventions according to the main categories of threat addressed by TAMAR.  相似文献   
100.
Abstract

This paper describes systematic work undertaken in the field of atmospheric emissions from Portuguese Kraft pulp mills. The study led to the determination of emission factors from stationary sources, which proved to be an important tool for assessing the need for investment in air pollution abatement equipment, specifically for malodorous gases.  相似文献   
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