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181.
Foodborne transmission gastroenteritis (AGE) outbreak occurred during a celebration lunch in July, 2016, Brazil. All stool samples tested were positive for noroviruses (NoV) and phylogenetic analysis revealed that strains were genetically close to GII.17 Kawasaki_2014. These findings indicated circulation of NoV GII.17 Kawasaki_2014 in the Brazilian population, associated with AGE outbreak.  相似文献   
182.
Optimal foraging theory predicts that individuals should become more opportunistic when intraspecific competition is high and preferred resources are scarce. This density-dependent diet shift should result in increased diet breadth for individuals as they add previously unused prey to their repertoire. As a result, the niche breadth of the population as a whole should increase. In a recent study, R. Svanb?ck and D. I. Bolnick confirmed that intraspecific competition led to increased population diet breadth in threespine stickleback (Gasterosteus aculeatus). However, individual diet breadth did not expand as resource levels declined. Here, we present a new method based on complex network theory that moves beyond a simple measure of diet breadth, and we use the method to reexamine the stickleback experiment. This method reveals that the population as a whole added new types of prey as stickleback density was increased. However, whereas foraging theory predicts that niche expansion is achieved by individuals accepting new prey in addition to previously preferred prey, we found that a subset of individuals ceased to use their previously preferred prey, even though other members of their population continued to specialize on the original prey types. As a result, populations were subdivided into groups of ecologically similar individuals, with diet variation among groups reflecting phenotype-dependent changes in foraging behavior as prey density declined. These results are consistent with foraging theory if we assume that quantitative trait variation among consumers affects prey preferences, and if cognitive constraints prevent individuals from continuing to use their formerly preferred prey while adding new prey.  相似文献   
183.
As climate is an important driver of vegetation distribution, climate change represents an important challenge to forestry. We (1) identify prevailing bioclimatic conditions for 49 relevant forest species in Portugal and (2) assess future shifts under climate change scenarios. We compute two bioclimatic indices (aridity and thermicity) and a new composite index, at ~1 km spatial resolution, and overlap with the species’ current ranges. Locations are based on a digital inventory, while climate parameters for both recent-past (1950–2000) and future climates (2041–2060), under RCP4.5 and RCP8.5, are provided by a multi-model ensemble of climate simulations. Results for future scenarios highlight an overall warming and drying trend. Supramediterranean and mesomediterranean climates will be significantly reduced, while thermomediterranean climates will dramatically increase, from their almost absence in current conditions to an area coverage of ~54 % in 2041–2060 for RCP8.5. There is also a clear shift from hyper-humid and humid to sub-humid and from the latter to semi-arid climates (area coverage of ~13 % in 2041–2060 for RCP8.5). Lower thermomediterranean sub-humid to semi-arid zones will cover the southern half of Portugal. These projections identify the most vulnerable (e.g. Betula pubescens, Quercus pyrenaica and Castanea sativa) and the most adapted (e.g. Quercus suber, Q. rotundifolia, Ceratonia siliqua, Pinus pinea, Quercus coccifera) species in future climates. Current bioclimatic zones associated with Eucalyptus globulus and Pinus pinaster, economically relevant species, will be moderately reduced and relocated. Possible adaptation measures are discussed to improve forest resilience to climate change, while maintaining its economic and environmental benefits.  相似文献   
184.

One of the most serious externalities of agricultural activity relates to greenhouse gas emissions. This work tests this relationship for the Portuguese case by examining data compiled since 1961. Employing cointegration techniques and vector error correction models (VECMs), we conclude that the evolution of the most representative vegetables and fruits in Portuguese production are associated with higher controls on the evolution of greenhouse gas emissions. Reversely, the evolution of the output levels of livestock and the most representative animal production have significantly increased the level of CO2 (carbon dioxide) reported in Portugal. We also analyze the cycle length of the long-term relationship between agricultural activity and greenhouse gas emissions. In particular, we highlight the case of synthetic fertilizers, whose values of CO2 have quickly risen due to changes in Portuguese vegetables, fruit, and animal production levels.

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185.
Bulk atmospheric deposition measurements for selected persistent toxic substances (PTS) were performed along environment gradients (urban–suburban–rural–background sites) in Brazil. The aim with this work is to investigate the fate of PTS and their emissions in South America, particularly along environment transects. Bulk sampler systems (polyurethane foams, 1?×?1 m2) were fixed along environment gradients (urban–suburban–rural–background) over summer and winter periods (2005–2007) at sites of different climate zones of Brazil. Organochlorine pesticides (OCs) and polychlorinated biphenyls (PCBs) were analyzed by gas chromatography coupled to electron capture detector (Shimadzu 2010, 20i GC-ECD). Urban sites reported the highest deposition rates for all PTS, ranging from tens to thousands of pictograms per square meter per day. Basically, there were no obvious seasonal differences in deposition rate concentrations for PTS along the urban–suburban–rural–background gradient. Dichlorodiphenyltrichloroethane (DDT) and its metabolites were the OCs most frequently detected at relatively high deposition rate levels (>1,000 pg m?2 day?1). Other legacy and current-use pesticides such as hexachlorocyclohexanes, endosulfans, hexachlorcyclobenzine, dieldrin, aldrin, metoxichlor, and chlodanes were also detected at lower deposition rate levels (10–100 pg m?2 day?1). PCBs were detected at extremely high deposition rate levels (1,000–10,000 pg m?2 day?1) with highest contributions from the tetra-PCBs (PCB-52, PCB-44, PCB-66, PCB-81, and PCB-77) and penta-PCB congeners (PCB-101, PCB-105, PCB-114, PCB-118, and PCB-126). The greatest deposition rate concentrations for total PCBs were mainly detected at urban sites in connection with high population densities. The observed high deposition rate concentrations for PCBs and DDTs at urban sites are probably associated with old PTS stocks emissions. For PCBs in particular, the high levels are strongly associated with local population densities, highlighting the effect of local/regional urban sources on these target PTS. These results are important to show that even though the use of PTS is regulated, the deposition of selected PTS is still impacted by local and regional emissions in Brazil and may be related to the historical and continued emissions from old PTS stocks.  相似文献   
186.
We report seasonal variation in CH(4) and N(2)O emission rate from solid storage of bovine manure in Delhi as well as emission factors and emission inventory from manure management systems in India. Emission flux observed in the year 2002-2003 was 4.29+/-1, 4.84+/-2.44 and 12.92+/-4.25 mg CH(4)kg(-1)dung day(-1), as well as 31.29+/-4.93, 72.11+/-16.22 and 6.39+/-1.76 microgN(2)O kg(-1)dung day(-1) in winter, summer and rainy seasons, respectively. CH(4) emission factors varied from 0.8 to 3.3 kg hd(-1)year(-1) for bovines and were lower than IPCC-1996 default values. N(2)O emission factors varied from 3 to 11.7 mg hd(-1)year(-1) from solid storage of manure. Inventory estimates were found to about 698+/-27 Gg CH(4) from all manure management systems and 2.3+/-0.46 tons of N(2)O from solid storage of manure for the year 2000.  相似文献   
187.
Although pesticides have been useful in agriculture pest control, there is a considerable risk for human health and damage to ecosystems. Carbaryl is a carbamate often taken as a safe insecticide, although data on metabolic activities is still scarce, viz. mitochondrial toxicity. Therefore, it is the goal of this work to assay the compound on isolated mitochondria, a biochemical model already used with other pesticides. Mitochondria isolated from the livers of Wistar rats were assayed for bioenergetic parameters, namely mitochondrial respiration, membrane potential, membrane integrity and enzyme activities. For higher concentrations, it was observed that carbaryl has a depressive effect on mitochondrial respiration and on the generation of mitochondrial membrane potential, but with preservation of membrane integrity. A locus between Complex II and III appears particularly affected and the mitochondrial phosphorylation system relatively insensitive. Therefore, carbaryl inhibits mitochondrial respiration without affecting the phosphorylation complex. Carbaryl is toxic for mitochondria, although at concentrations higher as compared with other insecticide compounds. Mitochondrial toxicity should be excluded as one of the primary causes for carbaryl immediate toxicity, as concluded from the range of concentrations where carbaryl shows effective mitochondrial toxicity.  相似文献   
188.
The short term (eco)toxicity potential of fresh and stabilized textile sludges, as well as the short term (eco)toxicity of leachates obtained from both fresh and stabilized textile sludges, was evaluated by a battery of toxicity tests carried out with bacteria, algae, daphnids, fish, earthworms, and higher plants. The (eco)toxicological results showed that, after 120 d of stabilization, the experimental loading ratio of 25% sludge:75% soil (v/v) (equivalent to 64.4 ton/ha) did not significantly increase toxicity effects and increased significantly the biomass yield for earthworms and higher plants. The rank of biological sensitivity endpoints was: Algae approximately Plant biomass > Plant germination approximately Daphnids > Bacteria approximately Fish > Annelids. The lack of short term toxicity effects and the stimulant effect observed with higher plants and earthworms are good indications of the fertilizer/conditioner potential of this industrial waste, which after stabilization can be used in the restoration of a non-productive forest soil.  相似文献   
189.
Environmental Science and Pollution Research - This study investigated the influence of the sewage sludge (SS) soil amendment on the chronic toxicity of imidacloprid (through the seed dressing...  相似文献   
190.
Journal of Material Cycles and Waste Management - Sewage sludge (SS) is a residue resulting from wastewater treatment, which is widely increasing due to population growth and economic development....  相似文献   
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