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81.
Mussels of the genus Mytilus are widespread in both northern and southern hemispheres. Mytilus taxa are very important components of marine coastal ecosystems, but are difficult to differentiate morphologically. Sequencing and Sequenom MassARRAY iPLEX genotyping technology was used to identify and verify novel SNP markers in three European taxa of Mytilus: M. edulis, M. galloprovincialis, and M. trossulus. SNPs were localized in coding and non-coding sequences of some functionally important genes. Eight SNPs located in genes of the histone family, hsp70 and p53, were discovered and applied as novel markers for Mytilus taxa on a large European scale. Five of these differentiated the M. trossulus genome, two M. galloprovincialis, and one M. edulis. Other SNPs differentiated populations within taxa. The new SNPs will be a valuable tool for population studies of European Mytilus mussels. The percentage of polymorphic SNPs ranged from 19 to 100 % in 24 samples of mussels studied. Populations from Scotland, Mecklenburg Bight, and Norway had over 90 % polymorphic loci. Most loci were in Hardy–Weinberg equilibrium in all samples except for the one from Scotland. The highest percentages of heterozygotes were observed in the Atlantic (Banyuls and Vigo) and North Sea (Tjarno and Westerschelde) populations. An excess of homozygotes was observed in samples from Scotland, Norway, and the Barents Sea. Correspondence and Structure analysis also demonstrated the great heterogeneity of these three samples.  相似文献   
82.
The purpose of the presented research is to identify local community opinions toward ecological problems in one of the mountainous region of Georgia (Upper Svaneti), to analyze how population ‘perceive, experience, and interpret’ the social, and ecological issues.

The paper is based on the results of Upper Svanet ipopulation’s survey which was carried out by the authors of presented paper during the August of 2015 and 2016.The questionnaire was elaborated taking into account the peculiarities of the region. Stratified-cluster selection method was used for selection of respondents and database compilation. For statistical analysis of polling data the SPSS package was used.

Based on the statistical analysis of survey results, the following issues have been studied: the most important ecological problems, environmental problems with respect to socio-economic ones, information sources on ecological problems, people’s trust in environmental issues, awareness level of the population on environmental policy, their personal contribution in environmental protection, ways to solve ecological problems, implemented environmental measures.

The obtained results are important to foster mountain population’s active participation in processes that contribute to decision-making processes, planning and implementing programs for sustainable development.  相似文献   

83.

Background

This paper aims to investigate the correlations between the concentrations of nine heavy metals in moss and atmospheric deposition within ecological land classes covering Europe. Additionally, it is examined to what extent the statistical relations are affected by the land use around the moss sampling sites. Based on moss data collected in 2010/2011 throughout Europe and data on total atmospheric deposition modelled by two chemical transport models (EMEP MSC-E, LOTOS-EUROS), correlation coefficients between concentrations of heavy metals in moss and in modelled atmospheric deposition were specified for spatial subsamples defined by ecological land classes of Europe (ELCE) as a spatial reference system. Linear discriminant analysis (LDA) and logistic regression (LR) were then used to separate moss sampling sites regarding their contribution to the strength of correlation considering the areal percentage of urban, agricultural and forestry land use around the sampling location. After verification LDA models by LR, LDA models were used to transform spatial information on the land use to maps of potential correlation levels, applicable for future network planning in the European Moss Survey.

Results

Correlations between concentrations of heavy metals in moss and in modelled atmospheric deposition were found to be specific for elements and ELCE units. Land use around the sampling sites mainly influences the correlation level. Small radiuses around the sampling sites examined (5 km) are more relevant for Cd, Cu, Ni, and Zn, while the areal percentage of urban and agricultural land use within large radiuses (75–100 km) is more relevant for As, Cr, Hg, Pb, and V. Most valid LDA models pattern with error rates of <?40% were found for As, Cr, Cu, Hg, Pb, and V. Land use-dependent predictions of spatial patterns split up Europe into investigation areas revealing potentially high (=?above-average) or low (=?below-average) correlation coefficients.

Conclusions

LDA is an eligible method identifying and ranking boundary conditions of correlations between atmospheric deposition and respective concentrations of heavy metals in moss and related mapping considering the influence of the land use around moss sampling sites.
  相似文献   
84.
Synchronized spike activity is discussed as a possible representational code for object integration and as a neuronal basis of attention, perception and awareness. As a byproduct of experiments in which monkeys were trained to detect simple figures composed of single Gabor patches in a noisy background of similar elements, we found in special cases increased spike synchrony above chance level specifically related to figure detection. The long latency of this effect is difficult to interpret. It may be a sign of the cognitive state of an animal when it perceives the figure.  相似文献   
85.
Wetland protection regulations and guidelines often require the delineation of precise wetland boundaries on a case-by-case basis. In this study, conducted in the New Jersey Pinelands, an ecological characterization of vegetation composition, soil and hydrologic relationships along upland to wetland Pinus rigida - dominated transittions provided the basis for a multiparameter approach to wetland boundary delineation. The transitional data set was analyzed by direct gradient analysis, cluster analysis and ordination. It is concluded that vegetation composition can be a principal factor in delineating wetland boundaries along natural upland to wetland transitions. However, where distinct vegetation changes are not observed, a feature of our study sites, a multiparameter approach should be used.  相似文献   
86.
Roads, bridges, causeways, impoundments, and dikes in the coastal zone often restrict tidal flow to salt marsh ecosystems. A dike with tide control structures, located at the mouth of the Herring River salt marsh estuarine system (Wellfleet, Massachusetts) since 1908, has effectively restricted tidal exchange, causing changes in marsh vegetation composition, degraded water quality, and reduced abundance of fish and macroinvertebrate communities. Restoration of this estuary by reintroduction of tidal exchange is a feasible management alternative. However, restoration efforts must proceed with caution as residential dwellings and a golf course are located immediately adjacent to and in places within the tidal wetland. A numerical model was developed to predict tide height levels for numerous alternative openings through the Herring River dike. Given these model predictions and knowledge of elevations of flood-prone areas, it becomes possible to make responsible decisions regarding restoration. Moreover, tidal flooding elevations relative to the wetland surface must be known to predict optimum conditions for ecological recovery. The tide height model has a universal role, as demonstrated by successful application at a nearby salt marsh restoration site in Provincetown, Massachusetts. Salt marsh restoration is a valuable management tool toward maintaining and enhancing coastal zone habitat diversity. The tide height model presented in this paper will enable both scientists and resource professionals to assign a degree of predictability when designing salt marsh restoration programs.  相似文献   
87.
Chile is one of the most seismically active countries in the world. Earthquakes are periodic phenomena that test the quality of construction, as well as the capacity of the population to adapt to sharp changes in socio-environ-mental conditions.
Experience in this regard has demonstrated the desirability of being prepared, at the institutional level and at the level of the general population, to carry out investigations and to begin measures to cope with these catastrophes, in order to reduce damage and the interruption of normal life to a minimum.
In this paper some general aspects of the social and health impacts of the earthquake of 3rd March 1985 are examined. The shock affected the central area of Chile which contains 61% of the total population.
The earthquake occurred at 19:50 hours on Sunday, 3rd March, and was of magnitude 7.8. Recorded personal losses included 180 dead and 2,575 injured, and around 200,000 damaged or destroyed dwellings. The destruction also affected the infrastructure of the public services, such as energy, road, telecommunications and water supply, giving rise to an emergency in the provision of assistance.
Special reference is made to the effects, on the health care infrastructure, drinking water supply and, less important, on the behavior of some communicable intestinal diseases that are highly endemic in the area under study.  相似文献   
88.
The theory of relativity has been considered as one of the most abstract and most difficult theories at the turn of the century. Today relativity is taught at high schools. This process is explained here by the increased faith in this theory and by better verbal explanations of the twin paradox and other effects of relativity. The development of new audiovisual aides for the teaching of relativity and other fields of modern physics is seen here as one of the main didactical challenges for the future.  相似文献   
89.
It is generally accepted that the bioavailability of metals in sediments is influenced by the presence of acid volatile sulfides (AVS). The pore water hypothesis predicts that, if the molar concentration of simultaneously extracted metals (SEM) in a sediment is smaller than the molar concentration of AVS, the free metal ion activity in the pore water is very small and that consequently no metal toxicity in short-term toxicity tests is observed. In this study we examined (1) if this concept can be extended to predict the absence of chronic Ni toxicity to the oligochaete deposit-feeding worm Lumbriculus variegatus and (2) if the organic carbon normalized excess SEM; i.e. [SEM-AVS]/f(OC) predicts the magnitude of Ni toxicity to L. variegatus. A 28-day toxicity experiment was performed in which biomass production of L. variegatus was determined in two natural sediments with different [AVS] and f(OC), spiked at different Ni concentrations. The absence of toxicity is predicted correctly by the [SEM-AVS]<0 criterion when only the 0-1 cm surface layer of the sediment is considered, but not when the whole bulk sediment is considered (0-3 cm). In both sediments, the same [SEM-AVS]/f(OC) at the surface corresponds with a similar decrease in L. variegatus biomass. Thus, [SEM-AVS]/f(OC) in the surface layer accurately predicts the magnitude of toxicity. This measure is therefore a good estimator of toxicologically available Ni. On the other hand, the free Ni(2+) ion activity in the overlying water appeared to be an equally good predictor of the magnitude of toxicity. Consequently, it was not possible to determine the relative importance of the overlying water and pore water exposure route with the semi-static laboratory experiments.  相似文献   
90.
This study seeks to advance our understanding of the leadership consequences that may ensue when supervisors and their teams have similar versus differing orientations toward the past. Integrating a leader–team fit perspective with functional leadership theory, we cast incongruence between supervisor and team past temporal focus as a key antecedent of supervisors' active (i.e., task-oriented and relationship-oriented) and passive (i.e., laissez-faire) leadership behaviors toward the team. We tested our hypotheses in a team-level study that included a field sample of 84 supervisors and their teams using polynomial regression and response surface analyses. Results illustrated that supervisors demonstrated more task-oriented and relationship-oriented leadership when supervisors' and their team's past temporal focus were incongruent rather than aligned. Furthermore, in situations of supervisor–team congruence, supervisors engaged in less task-oriented and relationship-oriented leadership and more laissez-faire leadership with higher (rather than lower) levels of supervisor and team past temporal focus. In sum, these findings support a complex (mis)fit model such that supervisors' attention to the past may hinder their productive leadership behaviors in some team contexts but not in others. Hence, this research advances a novel, multiple-stakeholder perspective on the role of both supervisors' and their team's past temporal focus for important leadership behaviors.  相似文献   
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