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251.
Juliano Gonçalves Pereira Vanessa Mendonça Soares Fernanda Gil de Souza Leonardo Ereno Tadielo Emanoelli Aparecida Rodrigues dos Santos Mário Celso Sperotto Brum Andreia Henzel Eduarda Hallal Duval Fernando Rosado Spilki Wladimir Padilha da Silva 《Food and environmental virology》2018,10(4):365-372
The aim of this study was to investigate hepatitis A virus (HAV), hepatitis E (HEV), and rotavirus (RV) in fresh and processed meat traded on the border of Brazil with Argentina and Uruguay. In total, 159 samples of raw and processed foods of animal origin were collected in Paso de los Libres, Argentina (n?=?53 raw meat, n?=?24 processed meat) and Rivera, Uruguay (n?=?55 raw meat, n?=?18 processed meat), or were seized by the Brazilian International Agricultural Surveillance System—VIGIAGRO (Brazil–Argentina border) (n?=?8 raw meat, n?=?1 bush meat). All samples were tested for the presence of HAV, HEV, and RV genomes. HAV genes were detected in 18.23% of samples and RV genes in 23.89%. No HEV-positive samples were detected. HAV was also detected in two of the VIGIAGRO samples. Processed meats from Argentina and Uruguay had a higher rate of HAV and RV than raw meat (P?>?0.05). The median HAV in the Argentinian and Uruguayan samples was 6.9?×?104 and 3.5?×?103 copies/g, respectively. The presence of RV viral genes in raw meats from Argentina was significant, and this was not observed in processed meats. The presence of HAV and RV genes in a significant portion of products from Argentina and Uruguay is a potential source of human infection. This also indicates precarious conditions of acquisition, processing, and manipulation, which could be improved by improved regulation of food across borders. 相似文献
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253.
Martin Nyffeler Çağan H. Şekercioğlu Christopher J. Whelan 《Die Naturwissenschaften》2018,105(7-8):47
In this paper, we present an estimate of the predation impact of the global population of insectivorous birds based on 103 (for the most part) published studies of prey consumption (kg ha?1 season?1) of insectivorous birds in seven biome types. By extrapolation—taking into account the global land cover of the various biomes—an estimate of the annual prey consumption of the world’s insectivorous birds was obtained. We estimate the prey biomass consumed by the world’s insectivorous birds to be somewhere between 400 and 500 million metric tons year?1, but most likely at the lower end of this range (corresponding to an energy consumption of ≈?2.7?×?1018 J year?1 or ≈?0.15% of the global terrestrial net primary production). Birds in forests account for >?70% of the global annual prey consumption of insectivorous birds (≥?300 million tons year?1), whereas birds in other biomes (savannas and grasslands, croplands, deserts, and Arctic tundra) are less significant contributors (≥?100 million tons year?1). Especially during the breeding season, when adult birds feed their nestlings protein-rich prey, large numbers of herbivorous insects (i.e., primarily in the orders Coleoptera, Diptera, Hemiptera, Hymenoptera, Lepidoptera, and Orthoptera) supplemented by spiders are captured. The estimates presented in this paper emphasize the ecological and economic importance of insectivorous birds in suppressing potentially harmful insect pests on a global scale—especially in forested areas. 相似文献
254.
Takayuki Miura Sébastien Lhomme Jean-Claude Le Saux Philippe Le Mehaute Yvonnick Guillois Elizabeth Couturier Jacques Izopet Florence Abranavel Françoise S. Le Guyader 《Food and environmental virology》2016,8(3):194-199
A hepatitis E outbreak, which occurred on a small isolated island, provided an opportunity to evaluate the association between the number of hepatitis E cases in the community and the concentration of virus detected in sewage. Samples were collected from the different sewage treatment plants from the island and analyzed for the presence of hepatitis E (HEV) virus using real-time RT-PCR. We demonstrated that if 1–4 % of inhabitants connected to a WWTP were infected with HEV, raw sewage contained HEV at detectable levels. The finding that such a small number of infected people can contaminate municipal sewage works raises the potential of the further distribution of the virus. Indeed, investigating the routes of transmission of HEV, including the potential for sewage effluent to contain infectious HEV, may help us to better understand the epidemiology of this pathogen, which is considered to be an emerging concern in Europe. 相似文献
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256.
Population viability analysis (PVA) is widely used to assess population‐level impacts of environmental changes on species. When combined with sensitivity analysis, PVA yields insights into the effects of parameter and model structure uncertainty. This helps researchers prioritize efforts for further data collection so that model improvements are efficient and helps managers prioritize conservation and management actions. Usually, sensitivity is analyzed by varying one input parameter at a time and observing the influence that variation has over model outcomes. This approach does not account for interactions among parameters. Global sensitivity analysis (GSA) overcomes this limitation by varying several model inputs simultaneously. Then, regression techniques allow measuring the importance of input‐parameter uncertainties. In many conservation applications, the goal of demographic modeling is to assess how different scenarios of impact or management cause changes in a population. This is challenging because the uncertainty of input‐parameter values can be confounded with the effect of impacts and management actions. We developed a GSA method that separates model outcome uncertainty resulting from parameter uncertainty from that resulting from projected ecological impacts or simulated management actions, effectively separating the 2 main questions that sensitivity analysis asks. We applied this method to assess the effects of predicted sea‐level rise on Snowy Plover (Charadrius nivosus). A relatively small number of replicate models (approximately 100) resulted in consistent measures of variable importance when not trying to separate the effects of ecological impacts from parameter uncertainty. However, many more replicate models (approximately 500) were required to separate these effects. These differences are important to consider when using demographic models to estimate ecological impacts of management actions. 相似文献
257.
Cristina Dutra Vieira Maria Auxiliadora Roque de Carvalho Noil Amorim de Menezes Cussiol Maria Eugênia Alvarez-Leite Simone Gonçalves dos Santos Renata Maria da Fonseca Gomes Marcos Xavier Silva Luiz de Macêdo Farias 《Waste management (New York, N.Y.)》2009,29(4):1388-1391
When developing proper waste management strategies, it is essential to characterize the volume and composition of solid waste. The aim of this work was to evaluate the composition of dental waste produced by three dental health services in Belo Horizonte, Minas Gerais State, Brazil. Two universities, one public and one private, and one public dental health service were selected. Waste collection took place from March to November 2007. During this period, three samples were collected from each dental health service. The total amount of dental waste produced in one day of dental work was manually separated into three categories: infectious and potentially infectious waste, accounting for 24.3% of the total waste; non-infectious waste, accounting for 48.1%; and domestic-type waste, accounting for 27.6% (percentages are for mean weights of solid waste). Our results showed that most of the waste considered as biomedical may be misclassified, consequently making the infectious waste amount appear much larger. In addition, our results suggest that the best waste minimization method is recycling, and they help to define an appropriate waste management system in all three of the dental health services involved in this study. 相似文献
258.
Rui Lourenço Vincenzo Penteriani Maria del Mar Delgado Michela Marchi-Bartolozzi João Eduardo Rabaça 《Behavioral ecology and sociobiology》2011,65(9):1709-1714
Intraguild predation (IGP) has been explained in terms of competitor-removal, food-stress and predator-removal hypotheses.
Only the first two hypotheses have been fairly well studied. To test the predator-removal hypothesis as a force determining
IGP in avian predators, we performed a field experiment to simulate the presence of an IG predator (eagle owl Bubo bubo dummy) in the surrounding of the nests of four potential IG prey (black kite Milvus migrans, red kite Milvus milvus, booted eagle Aquila pennata and common buzzard Buteo buteo). To discard the possibility that an aggressive reaction towards the eagle owl was not related to the presence of the IG
predator, we also presented a stuffed tawny owl Strix aluco, which is a potential competitor but cannot be considered an IG predator of the studied diurnal raptors considered in the
experiment. While almost always ignoring the tawny owl, raptors chiefly showed an interspecific aggressive behaviour towards
their IG predator. Our results seem to support the predator-removal hypothesis, as the IG prey may take advantage of the diurnal
inactivity of the IG predator to remove it from their territory. However, the recorded behaviour may be also considered as
a special variety of mobbing (i.e. a prey’s counter-strategy against its predator), where the mobber is sufficiently powerful
to escalate predator harassment into deliberate killing attempts. In their turn, eagle owls can respond with an IG predatory
behaviour aimed at removing IG prey species which are highly aggressive mobbers. 相似文献
259.
260.
Nicolae Scarlat Milan Martinov Jean-François Dallemand 《Waste management (New York, N.Y.)》2010,30(10):1889-1897
This paper provides a resource-based assessment of the available agricultural crop residues for bioenergy production in the European Union, at the level of the 27 Member States. The assessment provides the amount of the residues produced, collected, their present uses and the residues left available for bioenergy. This study considers the crop production and yields and multi-annual yield variation for each crop. The calculation was based on specific residues to product ratios, which were determined, depending on the crop type and crop yield. Sustainable removal rates were considered in order to protect soil fertility. The results show large spatial and temporal variations of available crop residues within EU27. The average amount of crop residues available for bioenergy in EU27 was estimated at 1530 PJ/year, with a variation between 1090 and 1900 PJ/year. The average value represents about 3.2% in final energy consumption in the EU27 while the variation 2.3–4%. This variation, which is even larger at the level of Member States, may result in shortages in biomass supply in some years, when crop residues are available in a lower amount than the average. 相似文献