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991.
Aichivirus 1 (AiV-1) is an enteric virus with 30 nm in diameter, belonging to the genus Kobuvirus in the Picornaviridae family being a causative agent of gastroenteritis in humans. The transmission is via the fecal-oral route, through person to person contact, recreation in contaminated waters, or through the consumption of contaminated food or water. The aim of this study was to determine the frequency and the molecular characterization of AiV-1 in wastewater from Uruguay. Biweekly collections from March 2011 to February 2012 were performed in the cities of Bella Unión, Salto, Paysandú, and Fray Bentos, northwestern region of Uruguay. A total of 96 samples were collected; viruses were concentrated by ultracentrifugation, and AiV-1 was detected by using a nested PCR with primers directed to a conserved region (3CD junction) of the viral genome. A high frequency of AiV-1 (n = 54) was observed at all the cities analyzed mainly in the colder months of the year. AiV-1 was not evidenced as an appropriate viral fecal indicator since when compared with other previously detected enteric viruses, no correlation was observed. All 13 characterized AiV-1 belonged to the genotype B after the phylogenetic analysis performed with the sequences obtained from the first round PCR amplicon. This study demonstrates that AiV-1 is a frequently detected enteric viruses present in wastewater and excreted by infected persons in the northwestern region of Uruguay.  相似文献   
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994.
Understanding of spatio-temporal patterns of sensitive fish species such as skates (Rajidae) is essential for implementation of conservation measures. With insufficient survey data available for these species in Portuguese Continental waters, this study shows that fishery-dependent data associated with fishers’ knowledge can be used to identify potential Essential Fish Habitats (EFH) for seven skate species. Sites with similar geomorphology were associated with the occurrence of juveniles and/or adults of the same group of species. For example, sites deeper than 100 m with soft sediment include predominantly adults of Raja clavata, and are the habitat for egg deposition of this species. Raja undulata and R. microocellata are the more coastal species, preferring sand or gravel habitats, while coastal areas with rocks and sand seabed are potential nursery areas for R. brachyura, R. montagui and R. clavata. The main output of this study is the identification of preferential fishing sites enclosing potential EFH for some species, associated with egg-laying and nursery grounds. The location of these areas will be considered for future seasonal closures, and studies will be conducted to evaluate the biological and socio-economic impacts of such measures. As in the past, fishermen will collaborate in the process of evaluating those impacts, since they have practical and applied knowledge that is extremely valuable for evaluating the advantages and disadvantages of such closures. In conclusion, this study is a first contribution to the understanding and identification of EFH for skate species, associated with nursery and egg deposition sites, with direct application to management.  相似文献   
995.
Summary

Adsorption of chlorfenvinphos and methidathion from dissolutions on H+, Ca++, Na+ and K+ are studied. In all cases the saturating cation distinctly influenced the Freundlich‐type adsorption, with adsorption decreasing in the following sequence: H+> Ca++> Na+ > K+. Chlorfenvinphos adsorption was slightly greater than methidathion in two clays, and the adsorption extent for them in kaolinite is slower that bentonite.  相似文献   
996.
R Tandlich  B Brezná  K Dercová 《Chemosphere》2001,44(7):1547-1555
The effect of two terpenes, carvone and limonene, on the biodegradation of DELOR 103, a commercial mixture of polychlorinated biphenyls (PCBs), by Pseudomonas stutzeri, an isolate from long-term PCB-contaminated soil, was studied in detail. The addition of both carvone and limonene as potential inducers of the dioxygenase metabolic pathway exerted an enhancing effect on PCB biodegradation when glycerol and xylose were used as carbon sources, whereas no such effect could be determined with biphenyl and glucose as substrates. Promising biodegradation values were determined with xylose as carbon source and carvone as terpene inducer. In this system, 30-70% of the congeners were degraded in the presence of 10 mg l(-1) and 20 mg l(-1) carvone, respectively, irrespective of the used concentration, whereas only 7-37% of individual PCB congeners were eliminated from the system without terpene addition.  相似文献   
997.
In Portuguese waters, thornback ray Raja clavata spawns mainly between May and January, although females and males in spawning condition are found throughout the year. The maturation process can be divided into three main phases by using information on gonad weight, oviducal gland and uterus width in females and on gonad weight, clasper length and sperm duct width in males. Females attain length-at-first-maturity at 784 mm and males at 676 mm, at ages of 7.5 and 5.8 years, respectively. In females larger than length-at-first-maturity, a resting stage was identified characterized by low gonadosomatic index and well-developed oviducal glands and uteri. These results along with the low proportion of adult females that are effectively reproducing per month demonstrated that the thornback ray cannot be considered a continuous spawner as described in other studies. Fecundity was determinate with about 35 eggs released per batch. During the spawning season, a total of four batch episodes occur indicating that the total fecundity was approximately 136 eggs per female. Regional differences may exist in the reproductive strategy of the species, namely on the duration of the spawning season, length-at-first-maturity, and fecundity, which can be related to a more intense fishing pressure in northern European waters.  相似文献   
998.
There are no observations for methane emissions from landfill waste in Ireland. Methane emissions are imputed from waste data. There are intermittent data on waste sent to landfill. We compare two alternative ways to impute the missing waste “data” and evaluate the impact on methane emissions. We estimate Irish historical landfill quantities from 1960–2008 and Irish methane emissions from 1968–2006. A model is constructed in which waste generation is a function of income, price of waste disposal and, household economies of scale. A transformation ratio of waste to methane is also included in the methane emissions model. Our results contrast significantly with the Irish Environmental Protection Agency’s (EPA) figures due to the differences in the underlying assumptions. The EPA’s waste generation and methane emission figures are larger than our estimates from the early 1990s onwards. Projections of the distance to target show that the EPA overestimates the required policy effort.  相似文献   
999.
Environmental Chemistry Letters - Steroids are abundant in living organisms and are responsible for various biological functions. They are good candidates for inclusion complexes formation with...  相似文献   
1000.
Assessing biodiversity vulnerability to future climate change is essential for developing robust adaptation strategies. A number of vulnerability assessment methodologies have been developed, from bioclimatic envelop models to more complex approaches that also consider biological traits and population status. However, the lack of comparative studies leaves the user to choose among the different methodologies without much guidance. This study applied three vulnerability assessment approaches to the Portuguese herpetofauna: (I) impact assessment approach based on bioclimatic models; (II) integrated vulnerability assessment approach, adding the evaluation of adaptive capacity to approach I; and (III) integrated vulnerability assessment and validation based on expert consultation. Results showed disagreement between the different approaches for 19 % of the species studied. Most differences were found between approach III and the two other approaches. All approaches showed advantages and limitations, the choice of a methodology being ultimately dependent on the study goals. Approach I has proven efficient to capture general vulnerability patterns. Approach II, although presenting results similar to approach I, allows for the identification of key factors affecting the species adaptive capacity and may be useful in tailoring adaptation measures. Approach III further allows us to identify knowledge gaps and to evaluate vulnerability when data availability or quality is reduced. Further, because this approach is based on an expert workshop, it has proven a perfect means to build on the vulnerability assessment results to identify indicator species and prioritize specific adaptation options.  相似文献   
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