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41.
Wild polioviruses still remain endemic in three countries (Afghanistan, Pakistan, and Nigeria) and re-emergency of wild polio has been reported in previously polio-free countries. Environmental surveillance has been used as a supplementary tool in monitoring the circulation of wild poliovirus (PVs) and/or vaccine-derived PVs even in the absence of acute flaccid paralysis cases. This study aimed to monitor the presence of polioviruses in wastewater samples collected at one wastewater treatment plant located in the municipality of Rio de Janeiro, Brazil. From December 2011 to June 2012 and from September to December 2012, 31 samples were collected and processed. RD and L20B cell cultures were able to isolate PVs and non-polio enteroviruses in 27/31 samples. Polioviruses were isolated in eight samples (type 1 Sabin = 1, type 2 Sabin = 5, and type 3 Sabin = 2). Vaccine-derived polioviruses were not detected nor evidence of recombination with other PVs or non-polio enterovirus serotypes were observed among the isolates. The Sabin-related serotypes 2 and 3 presented nucleotide substitutions in positions associated with the neurovirulent phenotype at the 5′-UTR. Changes in important Amino acid residues at VP1 were also observed in the serotypes 2 and 3. Environmental surveillance has been used successfully in monitoring the circulation of PVs and non-polio enteroviruses and it is of crucial importance in the final stages of the WHO global polio eradication initiative. Our results show the continuous circulation of Sabin-like PVs and non-polio enteroviruses in the analyzed area during the study period.  相似文献   
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Mutagenic and recombinagenic activity of surface waters in the Guaíba Hydrographic Region (RS, Brazil) was investigated using the SMART in Drosophila melanogaster. Two positive results in Caí River (September 2000 and August 2001) and in Taquari River (August 2001 and February 2002)--linked to direct recombinagenic toxicants were observed. In Jacuí samples, an indirect mutagenic and recombinagenic action was detected in a September 2000 collection and a direct recombinational activity was observed in February 2002. Also in February 2002--samples from Dilúvio Brook and Guaíba Lake (GPC) were able to induce wing spots by mitotic recombinagenesis. The former sampling site showed toxicants to have a direct action, and the latter an increment in mitotic recombination that depended on metabolic action. The SMART wing test shows that all positive responses were mainly related to homologous mitotic recombination.  相似文献   
44.

Adaptation research has changed significantly in recent years as funders and researchers seek to encourage greater impact, ensure value for money and promote interdisciplinarity across the natural and social sciences. While these developments are inherently positive, they also bring fresh challenges. With this in mind, this paper presents an agenda for the next generation of climate adaptation research for development. The agenda is based on insights from a dialogue session held at the 2016 Adaptation Futures conference as well as drawing on the collective experience of the authors. We propose five key areas that need to be changed in order to meet the needs of future adaptation research, namely: increasing transparency and consultation in research design; encouraging innovation in the design and delivery of adaptation research programmes; demonstrating impact on the ground; addressing incentive structures; and promoting more effective brokering, knowledge management and learning. As new international funding initiatives start to take shape, we underscore the importance of learning from past experiences and scaling-up of successful innovations in research funding models.

  相似文献   
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Environmental Science and Pollution Research - Laccases produced by Leucoagaricus gongylophorus act in lignocellulose degradation and detoxification processes. Therefore, the use of L....  相似文献   
46.
The switch from hunting wild meat for home consumption to supplying more lucrative city markets in Amazonia can adversely affect some game species. Despite this, information on the amounts of wild meat eaten in Amazonian cities is still limited. We estimated wild meat consumption rates in 5 cities in the State of Amazonas in Brazil through 1046 door-to-door household interviews conducted from 2004 to 2012. With these data, we modeled the relationship between wild meat use and a selection of socioeconomic indices. We then scaled up our model to determine the amounts of wild meat likely to be consumed annually in the 62 urban centers in central Amazonia. A total of 80.3% of all interviewees reported consuming wild meat during an average of 29.3 (CI 11.6) days per year. Most wild meat was reported as bought in local markets (80.1%) or hunted by a family member (14.9%). Twenty-one taxa were cited as consumed, mostly mammals (71.6%), followed by reptiles (23.2%) and then birds (5.2%). The declared frequency of wild meat consumption was positively correlated with the proportion of rural population as well as with the per capita gross domestic product of the municipality (administrative divisions) where the cities were seated. We estimated that as much as 10,691 t of wild meat might be consumed annually in the 62 urban centers within central Amazonia, the equivalent of 6.49 kg per person per year. In monetary terms, this amounts to US$21.72 per person per year or US$35.1 million overall, the latter figure is comparable to fish and timber production in the region. Given this magnitude of wild meat trade in central Amazonia, it is fundamental to integrate this activity into the formal economy and actively develop policies that allow the trade of more resilient taxa and restrict trade in species sensitive to hunting.  相似文献   
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The effects of two paralytic shellfish toxin (PST) producing dinoflagellates, Alexandrium minutum Halim (high and low toxin strains) and Gymnodinium catenatum Graham, on the pelagic harpacticoid copepod Euterpina acutifrons Dana were tested in a series of experiments run from October 1994 to May 1995. In small volumes (350 ml), both strains of A. minutum (300 to 350 cells ml-1), and G. catenatum (175 cells ml-1), strongly reduced naupliar activity (about 30 and 17% were inactive after 24 h, respectively). Activity is here defined as movement. In medium volumes (6 litre), 40% of nauplii incubated with the high toxin strain of A. minutum (1000 cells ml-1) and 8% of nauplii incubated with cell-free filtrate of the same culture were inactive after 24 h; these values increased to 50 and 30% respectively after 3 d. In large volumes (20 litre), adult copepods incubated with A. minutum (1000 and 10000 cells ml-1) for 5 d revealed only trace levels of PSP-toxins (paralytic shellfish poisoning) in the extracts analysed by HPLC. With both strains of A. minutum (1000 and 10000 cells ml-1), 10 to 15% of the copepods were inactive after 1 to 2 d. It is suggested that E. acutifrons avoids feeding on the dinoflagellates after tasting a few cells, but that the dinoflagellates may exude toxins or other substances that affect the copepods. The inactivating effect of the toxic dinoflagellates on the nauplii was more rapid and stronger than on adult copepods, although strong inactivation and death were also observed in adults with time (up to 80% were inactive after 5 d of incubation with A. minutum). Still, in our experiments a considerable proportion of adult females incubated with the toxic dinoflagellates remained active and were able to produce viable eggs for several days.  相似文献   
49.
The major pigment of a marine micro-organism was identified as prodigiosin on the basis of analytical and spectral data. Two minor pigments were tentatively assigned structures, from thin-layer chromatography (TLC) and mass spectral data, as prodigiosin homologs with 3-n-hexyl and 3-n-heptyl side-chains. The micro-organism was classified as a new Pseudomonas species on the basis of its morphological and biochemical characteristics. It was named Pseudomonas magnesiorubra (ATCC No. 21856).  相似文献   
50.
This study analyzes the options for meeting power demand in the Brazilianpower sector through the year 2015. Three policy cases are constructedto test economic and environmental policy measures against a baseline:advanced technologies scenario, environmental control scenario and carbon(C) elimination scenario. Least-cost modeling simulated these scenarios throughchanges in emissions fees and caps, costs for advanced technologies,demand side efficiency, and clean energy supplies. Results show that, in theabsence of alternative policies, new additions to Brazil's electric powersector will shift rapidly from hydroelectricity to combined-cycle natural gasplants. When the cost of environmental impacts are incorporated in theprice of power, the least-cost mix of electric power generation technologycould change in other ways. In all scenarios, energy efficiency andcogeneration play an important role in the least-cost power solution. Savingelectricity through increased efficiency offsets the needs for new supply andhas enormous potential in Brazil's industrial sector. Efficiency also reducesthe environmental burden associated with electricity production andtransmission, without compromising the quality of the services demandedby end users. Interesting enough, carbon dioxide (CO2) emissions will remainrelatively low under almost every conceivable scenario.  相似文献   
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