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101.
Four antennae-specific proteins (AaegOBP1, AaegOBP2, AaegOBP3, and AaegASP1) were isolated from the yellow fever mosquito, Aedes aegypti and their full-length cDNAs were cloned. RT-PCR indicated that they are expressed in female and, to a lesser extent, in male antennae, but not in control tissues (legs). AaegOBP1 and AaegOBP3 showed significant similarity to previously identified mosquito odorant-binding proteins (OBPs) in cysteine spacing pattern and sequence. Two of the isolated proteins have a total of eight cysteine residues. The similarity of the spacing pattern of the cysteine residues and amino acid sequence to those of previously identified olfactory proteins suggests that one of the cysteine-rich proteins (AaegOBP2) is an OBP. The other (AaegASP1) did not belong to any group of known OBPs. Structural analyses indicate that six of the cysteine residues in AaegOBP2 are linked in a similar pattern to the previously known cysteine pairing in OBPs, i.e., Cys-24–Cys-55, Cys-51–Cys-104, Cys-95–Cys-113. The additional disulfide bridge, Cys-38–Cys-125, knits the extended C-terminal segment of the protein to a predicted 2-helix. As indicated by circular dichroism (CD) spectra, the extra rigidity seems to prevent the predicted formation of a C-terminal -helix at low pH.Electronic Supplementary Material  Supplementary material is available for this article if you access the article at . A link in the frame on the left on that page takes you directly to the supplementary material.  相似文献   
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103.
One of the key determinants of success in biodiversity conservation is how well conservation planning decisions account for the social system in which actions are to be implemented. Understanding elements of how the social and ecological systems interact can help identify opportunities for implementation. Utilizing data from a large‐scale conservation initiative in southwestern of Australia, we explored how a social–ecological system framework can be applied to identify how social and ecological factors interact to influence the opportunities for conservation. Using data from semistructured interviews, an online survey, and publicly available data, we developed a conceptual model of the social–ecological system associated with the conservation of the Fitz‐Stirling region. We used this model to identify the relevant variables (remnants of vegetation, stakeholder presence, collaboration between stakeholders, and their scale of management) that affect the implementation of conservation actions in the region. We combined measures for these variables to ascertain how areas associated with different levels of ecological importance coincided with areas associated with different levels of stakeholder presence, stakeholder collaboration, and scales of management. We identified areas that could benefit from different implementation strategies, from those suitable for immediate conservation action to areas requiring implementation over the long term to increase on‐the‐ground capacity and identify mechanisms to incentivize implementation. The application of a social–ecological framework can help conservation planners and practitioners facilitate the integration of ecological and social data to inform the translation of priorities for action into implementation strategies that account for the complexities of conservation problems in a focused way.  相似文献   
104.
Epidemiological studies typically use monitored air pollution data from a single station or as averaged data from several stations to estimate population exposure. In industrialized urban areas, this approach may present critical issues due to the spatial complexities of air pollutants which are emitted by different sources. This study focused on the city of Taranto, which is one of the most highly industrialized cities in southern Italy. Epidemiological studies have revealed several critical situations in this area, in terms of mortality excess and short-term health effects of air pollution. The aims of this paper are to study the variability of air pollutants in the city of Taranto and to interpret the results in relation to the applicability of the data in assessing population exposure. Meteorological and pollution data (SO2, NO2, PM10), measured simultaneously and continuously during the period 2006–2010 in five air quality stations, were analyzed. Relative and absolute spatial concentration variations were investigated by means of statistical indexes. Results show significant differences among stations. The highest correlation between stations was observed for PM10 concentrations, while critical values were found for NO2. The worst values were observed for the SO2 series. The high values of 90th percentile of differences between pairs of monitoring sites for the three pollutants index suggest that mean concentrations differ by large amounts from site to site. The overall analysis supports the hypothesis that various parts of the city are differently affected by the different emission sources, depending on meteorological conditions. In particular, analysis revealed that the influence of the industrial site may be primarily identified with the series of SO2 data which exhibit higher mean concentration values and positive correlations with wind intensity when the monitoring station is downwind from the industrial site. Results suggest evaluating the population exposure to air pollutants in industrialized cities by taking into account the possible zones of influence of different emission sources. More research is needed to identify an indicator, which ought to be a synthesis of several pollutants, and take into account the meteorological variables.  相似文献   
105.
Mangrove forests provide important ecosystem services, but are under constant pressure from natural, anthropogenic, and climate change related disturbances. Environmental drivers on mangrove change at large spatial scales, other than sea level rise, are not well understood. In here, we use spatially explicit methods to identify the main environmental drivers of mangrove coverage change over a decade in the landscape of the North coast of the Yucatan peninsula, Mexico. A post-supervised classification approach on seven SPOT 5 multispectral satellite images was used to construct thematic maps of mangrove coverage between 2004 and 2014. A linear regression model between the thematic maps was performed to estimate the mangrove coverage change rate per pixel. Climate surfaces for annual maximum, minimum and mean temperature, and annual mean and cumulative precipitation for the region were calculated for the period 1980–2009 using data obtained from the National Meteorological Service. The effect of environmental variables on mangrove coverage change rates was assessed with a boosted generalized additive model (boosted GAM). The lowest and highest overall accuracy obtained for the time series thematic maps were 87.14% (Kappa?=?0.78), and 97.5% (Kappa?=?0.95), respectively. The most influential environmental variables on mangrove coverage change were annual cumulative precipitation (21%), and annual maximum temperature (9%). Current climate change scenarios for the region predict an increase in temperature and a decrease in precipitation, intensifying environmental stress on this ecosystem. Therefore, adequate management strategies are fundamental to help maintain the mangrove forest under changing environmental conditions.  相似文献   
106.
Impacts of urbanization on aquatic ecosystems are intensifying as urban sprawl spreads across the global land base. The urban stream syndrome (USS) identifies “symptoms” associated with urban development including changes in biotic communities, hydrology, water chemistry, and channel morphology. Direct relationships between road density (as surrogate of urbanization) and indicators of the USS were identified for streams in the Toronto region. Significant negative relationships were revealed between road density and biological (fish and benthic macroinvertebrate) richness, diversity, and fish Index of Biotic Integrity scores. Significant positive relationships were found between road density and tolerant fish/benthic macroinvertbrates, benthos Family Biotic Index scores, mean summer stream temperature, stream flashiness, and several water quality variables. Analysis of biological data showed that only four fish species and a reduced number of benthic macroinvertebrate families remained at the most urbanized sites. Road density was found to be a major determinant in both the fish and benthic macroinvertebrate community structure.  相似文献   
107.
We report a female infant noted prenatally to have an umbilical cord mass. At birth, a labial strawberry haemangioma was noted. She subsequently developed an abdominal mass which was discovered to be a proliferating haemangioma, continuous with both the labial and the umbilical stump lesions.  相似文献   
108.
Mediterranean temporary ponds (MTPs) comprise an endangered habitat with several endemic species that can be found in many countries, mainly in the Mediterranean region but are disappearing at a high rate. For designing optimal conservation and management strategies for the particular ecosystems, appropriate characterization and classification of these ponds is necessary based on the different type of habitats and on their varying environmental conditions. This paper presents the current ecological status and the threats of Mediterranean temporary ponds and summarizes some management and conservation issues based on the existing experience on a regional level. Emphasis is given in the Greek MTPs with respect to their characteristics and the pressures received mainly from human activities such as agriculture and water overexploitation. Restoration practices should be commenced immediately aiming at the reestablishment of the ponds' hydroperiod and water quality at the natural levels.  相似文献   
109.
Antarctic krill, Euphausia superba, hatched from eggs and maintained for four years, were sampled periodically for age-pigment analysis. Extractable pigments from the eye and eyestalk ganglia were quantified using fluorescence intensity and standardised against protein. Three peak fluorescence intensities were detected at wavelengths of excitation 280 nm, emission 625 nm (pigment 1); excitation 355 nm, emission 510 nm (pigment 2); and excitation 463 nm, emission 620 nm (pigment 3). There was a positive correlation between the quantity of pigments 1 and 3 and the age of Antarctic krill. A model was developed to predict age from pigment 3 and to compare it with other age proxies (carapace length and eyeball diameter). The quantity of pigment 3 was the best predictor of age. The pigment method can discriminate between similar sized krill aged 12 and 36 months. Age pigments provide an improved tool for age estimation in Antarctic krill, particularly if used in conjunction with other demographic information.  相似文献   
110.
Soil microbes in temperate forest ecosystems are able to cycle several hundreds of kilograms of N per hectare per year and are therefore of paramount importance for N retention. Belowground C allocation by trees is an important driver of seasonal microbial dynamics and may thus directly affect N transformation processes over the course of the year. Our study aimed at unraveling plant controls on soil N cycling in a temperate beech forest at a high temporal resolution over a time period of two years, by investigating the effects of tree girdling on microbial N turnover. In both years of the experiment, we discovered (1) a summer N mineralization phase (between July and August) and (2) a winter N immobilization phase (November-February). The summer mineralization phase was characterized by a high N mineralization activity, low microbial N uptake, and a subsequent high N availability in the soil. During the autumn/winter N immobilization phase, gross N mineralization rates were low, and microbial N uptake exceeded microbial N mineralization, which led to high levels of N in the microbial biomass and low N availability in the soil. The observed immobilization phase during the winter may play a crucial role for ecosystem functioning, since it could protect dissolved N that is produced by autumn litter degradation from being lost from the ecosystem during the phase when plants are mostly inactive. The difference between microbial biomass N levels in winter and spring equals 38 kg N/ha and may thus account for almost one-third of the annual plant N demand. Tree girdling strongly affected annual N cycling: the winter N immobilization phase disappeared in girdled plots (microbial N uptake and microbial biomass N were significantly reduced, while the amount of available N in the soil solution was enhanced). This was correlated to a reduced fungal abundance in autumn in girdled plots. By releasing recently fixed photosynthates to the soil, plants may thus actively control the annual microbial N cycle. Tree belowground C allocation increases N accumulation in microorganisms during the winter which may ultimately feed back on plant N availability in the following growing season.  相似文献   
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