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91.
This study presents information on the use of medicinal animals in a semiarid area of northeast Brazil, a region where animals have recognized importance in local popular medicine. The information on the use of animals for medicinal purposes was obtained through semi-structured questionnaires, complemented by free interviews and informal conversations. The results obtained showed that the residents of the area studied utilize a considerable richness of animal species (n = 42) for medicinal purposes, as occurs in other areas of Brazil’s semiarid region, demonstrating that zootherapy represents an alternative form of health care that is important to the inhabitants of the region. There is a need for new investigations on medicinal fauna, aimed at promoting the sustainable use of eventual medicinal species and preserving popular knowledge associated with the use of animal species.  相似文献   
92.
Mycotoxins occurrence in wheat grains impose risks to human and animal health. The southern Brazil has favorable weather conditions for Fusarium graminearum infections and consequently for mycotoxins accumulation on grains. The goal of this study was to evaluate the behavior of new wheat commercial genotypes to Fusarium Head Blight (FHB), to control performance of new fungicide formulations and their relationship with mycotoxins concentration in grains. The manly mycotoxin occurrence on wheat grains in southern Brazil was deoxynivalenol (DON). Two cultivars showed high DON concentration above the tolerance limits (>3000 μg kg?1). Many other mycotoxins monitored presented concentrations below method detection limit. Satisfactory levels of fungicide effectiveness were achieved against F. graminearum. Some fungicides promoted a satisfactory decrease on DON accumulation in grains. The best results were obtained when prothioconazole was present. SDHI (Succinate dehydrogenase inhibitors) + QoI (Quinone outside inhibitors) fungicides showed benefic effects at FHB control at field, but it did not promote satisfactory reduction on DON contamination. Fungicides can be used satisfactory for FHB control and reduce DON contamination in grains in southern Brazil. The presence of prothioconazole should be recommended. Some genotypes showed high DON concentration and it was not directly related with FHB severity at field.  相似文献   
93.
The objective of the present study is to evaluate, determine, and apply alternatives for improving the quality of the process and the product, with an emphasis on sustainable practices, using an integrated multi-criteria method. For this purpose, an analysis was conducted at a chain of bakeries, aiming to highlight bottlenecks in the production process and in the product. With the support of a literature review, four criteria and seven alternatives were defined to overcome these bottlenecks and, at the same time, contribute to the sustainability of the organization. For data analysis, six decision makers were interviewed and, following their evaluations, an integrated method based on fuzzy AHP and fuzzy TOPSIS was created. The fuzzy AHP was adopted to establish the importance of the criteria, while the fuzzy TOPSIS was used to evaluate and classify the alternatives developed to bypass the bottlenecks. The results revealed that of the criteria, Criterion “Cr1 – Quality” was prioritized. On the other hand, the alternative with the best performance was “A3 – Physical Layout Reorganization”. Applying this alternative, the study demonstrates the results achieved such as reduction of errors and accident risks, as well as greater fluidity in the productive space. the present study also makes theoretical and managerial contributions to the field, bringing the theory closer to the reality of companies that operate in the food sector.  相似文献   
94.
95.
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   
96.
This paper reports on the field testing of a tunable diode laser trace gas analyzer system for micrometeorological monitoring of ammonia fluxes. This system uses infrared absorption spectroscopy to measure atmospheric ammonia concentrations and the fluxgradient method to relate the measured concentration gradient to a flux of ammonia. For the field tests, we monitored ammonia fuxes over three plots receiving different manure applications. Each plot was sampled for 15 or 30 min of each hour, producing a high-temporal resolution data set. Analysis of the system response showed that ammonia adsorption to the tubing walls was greatly reduced by the system design and did not interfere with the flux measurement.  相似文献   
97.
Combustion of hydrocarbon fuels with pure oxygen results in a different flue gas composition as combustion with air. Standard CFD spectral gas radiation models for air blown combustion are out of their validity range. The series of three articles provides a common spectral basis for the validation of new developed models. Part B of the series presents spectral measurements in the spectral range of 2.4–5.4 μm of a 70 kW turbulent natural gas flame in air blown combustion and in wet and dry oxyfuel combustion. The experimentally measured intensity spectra were compared with simulated spectra based on measured gas atmospheres. The line-by-line database HITEMP2010 and the two statistical-narrow-band models EM2C and RADCAL were used for the numerical simulation. The measured spectra showed large fluctuations due to turbulence. The up to 75% increased averaged experimental intensity compared to the simulated intensity pointed out the importance of the effect of turbulence-radiation-interaction in combustion simulations.  相似文献   
98.
Iron (Fe) and other trace elements such as Zn, Mn, Ni and Cu are known as key-factors in marine biogeochemical cycles. It is believed that ocean primary productivity blooms in iron deficient regions can be triggered by iron in aeolian dust. Up to now, scarce aerosol elemental composition, based on measurements over sea at the Western South Atlantic (WSA), exist. An association between the Patagonian semi-desert dust/Fe and chlorophyll-a variability at the Argentinean continental shelf is essentially inferred from models. We present here experimental data of Fe enriched aerosols over the WSA between latitudes 22°S–62°S, during 4 oceanographic campaigns between 2002 and 2005. These data allowed inferring the atmospheric Fe flux onto different latitudinal bands which varied from 30.4 to 1688 nmolFe m?2 day?1 (October 29th–November 15th, 2003); 5.83–1586 nmolFe m?2 day?1 (February 15th–March 6th, 2004) and 4.73–586 nmolFe m?2 day?1(October 21st–November 5th, 2005).  相似文献   
99.
This work proposes a procedure for the determination of total selenium content in shellfish after digestion of samples in block using cold finger system and detection using atomic fluorescent spectrometry coupled hydride generation (HG AFS). The optimal conditions for HG such as effect and volume of prereduction KBr 10 % (m/v) (1.0 and 2.0 ml) and concentration of hydrochloric acid (3.0 and 6.0 mol L?1) were evaluated. The best results were obtained using 3 mL of HCl (6 mol L?1) and 1 mL of KBr 10 % (m/v), followed by 30 min of prereduction for the volume of 1 mL of the digested sample. The precision and accuracy were assessed by the analysis of the Certified Reference Material NIST 1566b. Under the optimized conditions, the detection and quantification limits were 6.06 and 21.21 μg kg?1, respectively. The developed method was applied to samples of shellfish (oysters, clams, and mussels) collected at Todos os Santos Bay, Bahia, Brazil. Selenium concentrations ranged from 0.23?±?0.02 to 3.70?±?0.27 mg kg?1 for Mytella guyanensis and Anomalocardia brasiliana, respectively. The developed method proved to be accurate, precise, cheap, fast, and could be used for monitoring Se in shellfish samples.  相似文献   
100.
Abamectin is used as an acaricide and insecticide for fruits, vegetables and ornamental plants, as well as a parasiticide for animals. One of the major problems of applying pesticides to crops is the likelihood of contaminating aquatic ecosystems by drift or runoff. Therefore, toxicity tests in the laboratory are important tools to predict the effects of chemical substances in aquatic ecosystems. The aim of this study was to assess the potential hazards of abamectin to the freshwater biota and consequently the possible losses of ecological services in contaminated water bodies. For this purpose, we identified the toxicity of abamectin on daphnids, insects and fish. Abamectin was highly toxic, with an EC50 48 h for Daphnia similis of 5.1 ng L−1, LC50 96 h for Chironomus xanthus of 2.67 μg L−1 and LC50 48 h for Danio rerio of 33 μg L−1.  相似文献   
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