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61.
Protected areas are a cornerstone for forest protection, but they are not always effective during times of socioeconomic and institutional crises. The Carpathian Mountains in Eastern Europe are an ecologically outstanding region, with widespread seminatural and old‐growth forest. Since 1990, Carpathian countries (Czech Republic, Hungary, Poland, Romania, Slovakia, and Ukraine) have experienced economic hardship and institutional changes, including the breakdown of socialism, European Union accession, and a rapid expansion of protected areas. The question is how protected‐area effectiveness has varied during these times across the Carpathians given these changes. We analyzed a satellite‐based data set of forest disturbance (i.e., forest loss due to harvesting or natural disturbances) from 1985 to 2010 and used matching statistics and a fixed‐effects estimator to quantify the effect of protection on forest disturbance. Protected areas in the Czech Republic, Slovakia, and the Ukraine had significantly less deforestation inside protected areas than outside in some periods; the likelihood of disturbance was reduced by 1–5%. The effectiveness of protection increased over time in these countries, whereas the opposite was true in Romania. Older protected areas were most effective in Romania and Hungary, but newer protected areas were more effective in Czech Republic, and Poland. Strict protection (International Union for Conservation of Nature [IUCN] protection category Ia‐II) was not more effective than landscape‐level protection (IUCN III‐VI). We suggest that the strength of institutions, the differences in forest privatization, forest management, prior distribution of protected areas, and when countries joined the European Union may provide explanations for the strikingly heterogeneous effectiveness patterns among countries. Our results highlight how different the effects of protected areas can be at broad scales, indicating that the effectiveness of protected areas is transitory over time and space and suggesting that generalizations about the effectiveness of protected areas can be misleading.  相似文献   
62.

Bacillus sp. CL18 was investigated to propose a bioprocess for protease production using feathers as organic substrate. In feather broth (FB), containing feathers as sole organic substrate (1–100 g l?1), maximal protease production was observed at 30 g l?1 (FB30) after 6 days of cultivation, whereas increased feather concentrations negatively affected protease production and feather degradation. Protease production peaks were always observed earlier during cultivations than maximal feather degradation. In FB30, 80% of initial feathers mass were degraded after 7 days. Addition of glucose, sucrose, starch, yeast extract (2 g l?1), CaCl2, or MgCl2 (10 mmol l?1) to FB30 decreased protease production and feather degradation. FB30 supplementation with NH4Cl (1 g l?1) resulted in less apparent negative effects on protease production, whereas peptone (2 g l?1) increased protease yields earlier during cultivations (3 days). Through a central composite design employed to investigate the effects of peptone and NH4Cl (0.5–4.5 g l?1) on protease production and feather degradation, FB30 supplementation with peptone and NH4Cl (0.5–1.1 g l?1) increased protease production within a shorter cultivation time (5 days) and hastened complete feather degradation (6 days). Feather bioconversion concurs with sustainable production of value-added products.

  相似文献   
63.
Roelke, Daniel L., Leslie Schwierzke, Bryan W. Brooks, James P. Grover, Reagan M. Errera, Theodore W. Valenti, Jr., and James L. Pinckney, 2010. Factors Influencing Prymnesium parvum Population Dynamics During Bloom Initiation: Results from In-Lake Mesocosm Experiments. Journal of the American Water Resources Association (JAWRA) 46(1):76-91. DOI: 10.1111/j.1752-1688.2009.00392.x Abstract: The alga Prymnesium parvum forms large fish-killing blooms in many Texas lakes. In some of these lakes, however, P. parvum occurs but does not develop blooms. In this study, we investigated factors that may influence bloom initiation by conducting a series of in-lake experiments involving mixing of waters from Lake Whitney, which has a history of P. parvum blooms, with waters from Lake Waco where no blooms have occurred. In all experiments, the addition of Lake Waco waters resulted in a poorer performance of P. parvum. Various experimental treatments and field data show that differences in grazing, pathogens, nutrients, and salts between the two lakes were not likely factors that contributed to this observation. Industrial and agricultural contaminants, allelochemicals and algicidal chemicals were not measured as a part of this research. However, anthropogenic contaminants other than nutrients were not observed at levels exceeding water quality standards in Lake Waco in recent years. On the other hand, nuisance cyanobacteria are common in Lake Waco, where Microcystis sp. and Anabaena sp. were abundant during the initiation of our experiments, both taxa are known to produce chemicals with allelopathic properties. In addition, the emergent field of algal-heterotrophic bacteria interactions suggests that chemicals produced by heterotrophic bacteria should not be overlooked. Further research focusing on the chemical interactions between cyanobacteria and P. parvum, as well as the potential role of algicidal bacteria, in the initiation of P. parvum blooms is necessary, as it may be important to the management of these blooms.  相似文献   
64.
Environmental Science and Pollution Research - The most common mycotoxin found in European foodstuffs, especially unprocessed grains, is deoxynivalenol (DON), which inhibits proteosynthesis and...  相似文献   
65.
Environmental Science and Pollution Research - Dimethoate ([O,O-dimethyl S-(N-methylcarbamoylmethyl) phosphorodithioate]) is an organophosphate insecticide and acaricide widely used for...  相似文献   
66.
Environmental Science and Pollution Research - To minimize the awful situation confronting the entire globe, the global warming danger has raised the intensity of consciousness from all areas of...  相似文献   
67.
Environmental Science and Pollution Research - The Southeast Asian countries have experienced significant degrees of economic growth over the years but have not managed to safeguard their...  相似文献   
68.
Norovirus (NoV) is recognized as the most common cause of foodborne outbreaks. In 2014, an outbreak of acute gastroenteritis occurred on a cruise ship in Brazil, and NoV became the suspected etiology. Here we present the molecular identification of the NoV strains and the use of sequence analysis to determine modes of virus transmission. Food (cream cheese, tuna salad, grilled fish, orange mousse, and vegetables soup) and clinical samples were analyzed by ELISA, conventional RT-PCR, qRT-PCR, and sequencing. Genogroup GII NoV was identified by ELISA and conventional RT-PCR in fecal samples from 5 of 12 patients tested (41.7%), and in the orange mousse food sample by conventional RT-PCR and qRT-PCR. Two fecal GII NoV samples and the orange mousse GII NoV sample were successfully genotyped as GII.Pe (ORF 1), revealed 98.0–98.8% identities among them, and shared phylogenetically distinct cluster. Establishing the source of a NoV outbreak can be a challenging task. In this report, the molecular analysis of the partial RdRp NoV gene provided a powerful tool for genotyping (GII.Pe) and tracking of outbreak-related samples. In addition, the same fast and simple extraction methods applied to clinical samples could be successfully used for complex food matrices, and have the potential to be introduced in routine laboratories for screening foods for presence of NoV.  相似文献   
69.
Recruitment precision, i.e. the proportion of recruits that reach an advertised food source, is a crucial adaptation of social bees to their environment. Studies with honeybees showed that recruitment precision is not a fixed feature, but it may be enhanced by factors like experience and distance. However, little is known regarding the recruitment precision of stingless bees. Hence, in this study, we examined the effects of experience and spatial distance on the precision of the food communication system of the stingless bee Scaptotrigona mexicana. We conducted the experiments by training bees to a three-dimensional artificial patch at several distances from the colony. We recorded the choices of individual recruited foragers, either being newcomers (foragers without experience with the advertised food source) or experienced (foragers that had previously visited the feeder). We found that the average precision of newcomers (95.6 ± 2.61%) was significantly higher than that of experienced bees (80.2 ± 1.12%). While this might seem counter-intuitive on first sight, this “loss” of precision can be explained by the tendency of experienced recruits to explore nearby areas to find new rewarding food sources after they had initially learned the exact location of the food source. Increasing the distance from the colony had no significant effect on the precision of the foraging bees. Thus, our data show that experience, but not the distance of the food source, affected the patch precision of S. mexicana foragers.  相似文献   
70.
PROBLEM: A stated objective of driver education in North America is to produce safer drivers, typically defined as drivers less likely to crash. This paper examines the extent to which driver education has achieved this objective independently as well as the extent to which such programs can support the success of graduated licensing in reducing young driver crashes. In so doing, it discusses past experiences, recent developments, and the future direction of driver education and training in relation to graduated driver licensing. METHOD: Literature review and synthesis. RESULTS: Driver education programs have yet to demonstrate consistent attainment of their safety objectives. Moreover, they have not been found to enhance the safety effectiveness of graduated licensing programs--indeed, some practices, for example, "time discounts" for driver education have actually had a detrimental effect on teen safety. DISCUSSION: Despite its disappointing safety record to date, it is important not to abandon driver education. In particular, there are opportunities to improve driver education so that it achieves its safety objectives, and ensure that programs in the future complement graduated driver licensing and contribute to its overall safety benefits. Current and future efforts to improve driver education and better integrate it with graduated licensing programs, however, need to be rigorously evaluated to determine what does and does not work to reduce young driver crashes, and as importantly, to understand why this is the case. IMPACT ON INDUSTRY: Improved driver education integrated with graduated driver licensing has potential safety benefits.  相似文献   
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