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Different Geographical Regions (different + geographical_regions)
Selected AbstractsField theory for biogeography: a spatially explicit model for predicting patterns of biodiversityECOLOGY LETTERS, Issue 1 2010James P. O'Dwyer Abstract Predicting the variation of biodiversity across the surface of the Earth is a fundamental issue in ecology, and in this article we focus on one of the most widely studied spatial biodiversity patterns: the species,area relationship (SAR). The SAR is a central tool in conservation, being used to predict species loss following global climate change, and is striking in its universality throughout different geographical regions and across the tree of life. In this article we draw upon the methods of quantum field theory and the foundation of neutral community ecology to derive the first spatially explicit neutral prediction for the SAR. We find that the SAR has three phases, with a power law increase at intermediate scales, consistent with decades of documented empirical patterns. Our model also provides a building block for incorporating non-neutral biological variation, with the potential to bridge the gap between neutral and niche-based approaches to community assembly. Ecology Letters (2010) 13: 87,95 [source] Phenotypic and genotypic characterization of encapsulated Escherichia coli isolated from blooms in two Australian lakesENVIRONMENTAL MICROBIOLOGY, Issue 5 2005Michelle L. Power Summary Escherichia coli has long been used as an indicator organism for water quality assessment. Recently there has been an accumulation of evidence that suggests some strains of this organism are able to proliferate in the environment, a characteristic that would detract from its utility as an indicator of faecal pollution. Phenotypic and genotypic characterization of E. coli isolated from blooms in two Australian lakes, separated by a distance of approximately 200 km, identified that the blooms were dominated by three E. coli strains. A major phenotypic similarity among the three bloom strains was the presence of a group 1 capsule. Genetic characterization of a conserved region of the cps gene cluster, which encodes group 1 capsules, identified a high degree of genetic variation within the bloom isolates. This differs from previously described encapsulated E. coli strains which are highly conserved at the cps locus. The phenotypic or genotypic profiles of the bloom strains were not identified in 435 E. coli strains isolated from vertebrates. The occurrence of these encapsulated strains suggests that some E. coli have evolved a free-living lifestyle and do not require a host in order to proliferate. The presence of the same three strains in bloom events in different geographical regions of a temperate climate, and at different times, indicates that free-living E. coli strains are able to persist in these water reservoirs. This study provides further evidence of circumstances where caution is required in using E. coli as an indicator organism for water quality. [source] Survey ranking of job competencies by perceived employee importance: Comparing China's three regionsHUMAN RESOURCE DEVELOPMENT QUARTERLY, Issue 4 2006Jin Xiao The acquisition of skills that match job requirements has become an issue in human resource development. A uniform but vague list of desirable skills often provided by policymakers or advocated by scholars is used as a guide in education and training programs in China. Using survey data, this study analyzes the core skills that workforces in China consider to be important in carrying out job routines in different jobs, different industries, and different geographical regions. This study surveyed 25,933 employees from 397 randomly sampled firms of four counties in each of the East, Central, and West regions of China. Twenty kinds of job skills were deduced from interviews conducted in the field. Five categories of skills were identified by the employees: dispositional characteristics, technical know-how skills, job basics, problem solving, and communication. Using a hierarchical model, the analysis is focused on whether employees in different occupations ( for example, managerial, professional, salesperson, frontline workers) had different perceptions of required job skills. The results show both differences related to occupation and work experience and similarities in perceived job competencies among industries and across three regions. [source] Organizational culture in nursing schools in Turkey: faculty members' perspectivesINTERNATIONAL NURSING REVIEW, Issue 3 2009F. Kantek rn Background:, Among the benefits of examining an organization's culture are the opportunity to understand the basic mechanisms of the institutional and structural procedures, to determine the need for change and to ensure the development and satisfaction of the faculty members. Aim:, To determine the perceptions of faculty members of organizational culture at nursing schools in Turkey and to examine different perceptions in relation to demographic variables. Method:, The study was conducted with 180 faculty members from seven nursing schools in state universities located in different geographical regions of Turkey that granted permission for the study. All faculty members in these schools with at least 1 year of institutional experience were included in the research. No sampling was required. A demographic information form and an organizational culture scale were used as data collection materials. The organizational culture scale contains 30 items and resolves the organizational culture in three dimensions. The minimum score obtained was 1 and the maximum was 5. Findings:, The mean score for faculty members' in total scale was 3.40 (SD = 0.68), while it was 3.26 (SD = 0.77) for the management style dimension, 3.39 (SD = 0.73) for the organizational commitment/relations dimension and 3.68 (SD = 0.73) for the student-oriented dimension. There was no statistical difference between the perception of organizational culture and work experience at the institution, marital status or educational status, but there were differences in age, number of years in the profession and academic titles. Conclusion:, It was found that strong perceptions have been established in nursing schools in regard to student-oriented practices, and that groups consisting of senior academic personnel and experienced academicians are considered to be better at perceiving the importance of the organizational culture. The administrators are recommended to promote policies to enhance the participation in decision-making processes and regularly monitor the cultural changes in the organization. [source] The regulation of ecosystem functions by ecotypic variation in the dominant plant: a Spartina alterniflora salt-marsh case studyJOURNAL OF ECOLOGY, Issue 1 2002Denise M. Seliskar Summary 1Genetic differences among populations of a keystone species may affect ecosystem functional properties. We tested this by planting Spartina alterniflora from different geographical regions in a newly created salt marsh in Delaware, USA. 2Spartina alterniflora plants from morphologically distinct short-form (back marsh) populations were originally collected from Massachusetts (41°34, N), Delaware (38°47, N), and Georgia (31°25, N) in the USA and vegetatively propagated for 6 years in a salt water-irrigated common garden in Delaware before transfer to a newly created salt marsh. 3The magnitude of the expression of marsh functions in the created marsh, measured over 5 years, remained distinct in patches of each ecotype. End of season aerial biomass, below-ground biomass, root and rhizome distribution, canopy height, stem density, and carbohydrate reserves were closer to values reported for the plants' native sites than to those typical of Delaware. Thus, many of the plant features characteristic of particular latitudes appear to be under genetic control. Such ecotypic differentiation influences ecosystem function through keystone resource and keystone modifier activities. 4Respiration of the microbial community associated with either dead shoots or the soil varied with plant ecotype in the created wetland and the patterns reflected those reported for their native sites. High edaphic respiration under the Massachusetts ecotype was correlated with the high percentage of sugar in the rhizomes. Edaphic chlorophyll was greater under the canopies of the Massachusetts and Delaware ecotypes than under the Georgia canopy and exhibited a relationship similar to that of algal production rates reported for the native sites. Larval fish were most abundant in pit traps in the Massachusetts ecotype. [source] Comparative Sequence Analysis of Coat Protein Gene of Iranian Citrus tristeza virus IsolatesJOURNAL OF PHYTOPATHOLOGY, Issue 7-8 2005A. Barzegar Abstract Twenty-two isolates of Citrus tristeza virus (CTV) collected from two different geographical regions of Iran were characterized based on coat protein (CP) gene sequences. Thirteen virus isolates were collected from northern parts of Iran with high distribution of CTV infection and nine isolates were obtained from southern regions where the presence and aphid transmission of CTV was previously reported. All isolates were recovered from field trees showing varied CTV symptoms such as decline in most citrus varieties on sour orange rootstock, inverse pitting on some sour orange rootstocks below bud union, mild-to-moderate stem pitting on the trunk of some sweet orange. Isolates F, G, MB1, MB7, MB2, MB8, MB9, MB11 and MB17 were recovered from healthy looking Miyagawa Satsuma on trifoliate rootstock originally infected with CTV imported from Japan in late-1960s. The presence of virus in citrus samples was confirmed using polyclonal as well as monoclonal antibody. The CTV CP gene of all isolates was amplified by reverse transcriptase polymerase chain reaction (RT,PCR) using CP gene-specific primers yielding 672 bp amplicon. The restriction fragment length polymorphism (RFLP) profile, nucleotide and deduced amino acid sequences were analysed and compared with each other and also with some other exotic CP gene sequences of CTV isolates available in GenBank. Analysis of our data revealed that Iranian isolates have high similarity to California SY568 severe stem pitting and Japanese NUagA seedling yellows strains (up to 97%). The dendrogram generated from the deduced amino acid sequence could separate MB1, MB2, MB8, MB9, MB11 and MB17 isolates from others. However, no major dissociation between the isolates from northern and southern region could be obtained. [source] Isozyme Analysis and Soluble Mycelial Protein Pattern in Iranian Isolates of Several formae speciales of Fusarium oxysporumJOURNAL OF PHYTOPATHOLOGY, Issue 5 2004M. Mohammadi Abstract A total of 13 representative isolates of Fusarium oxysporum f. sp. melonis (FOM) from Iran, USA and France, eight isolates of seven formae speciales from Iran and one isolate of F. oxysporum f. sp. niveum from the USA were compared based on isozyme analysis and soluble mycelial protein pattern. Isozyme analyses of alkaline phosphatase (ALP), catalase (CAT), esterase (EST), malate dehydrogenase (MDH), superoxide dismutase (SOD) and xanthine dehydrogenase (XDH) revealed polymorphism among the F. oxysporum isolates in which 22 electrophoretic phenotypes (EP) were determined. At least 10 putative loci for these six enzymes were detected and they were all polymorphic. Maximum genetic diversity was observed in CAT, EST and XDH loci. Using UPGMA, the 22 isolates were separated into three main groups with one of the groups divided into two subgroups. Group I included isolates belonging to five formae speciales from Iran, whereas group II that included FOM isolates from both Iran and the USA was divided into two subgroups each containing the vast majority of the respective isolates from either country. Group III constituted FOM isolates from France and one pathogenic isolate on pepper from Iran. FOM isolates representing five different geographical regions from Iran belonged to two different races of 1 and 1,2Y and one vegetative compatibility group (VCG)0134 and thus were genetically homologous. Isozyme polymorphism in these isolates was highly correlated with VCG and geographical origins and to a lesser extent with races. Variations in soluble protein profile in FOM isolates were correlated with genetic distances determined in isozyme analysis. This study suggests that isozyme analysis could be a useful tool for identifying genetic diversity not only in FOM but also several formae speciales of F. oxysporum. [source] Germination ecology of the clonal herb Knautia arvensis: Regeneration strategy and geographic variationJOURNAL OF VEGETATION SCIENCE, Issue 4 2003Vigdis Vandvik Lid & Lid (1994) Abstract. We investigated germination responses and seed recruitment in the clonal grassland herb Knautia arvensis (Dipsacaceae) throughout its distributional range in Norway. Four predicted relationships between germination responses and field regeneration behaviour were tested using phytotron experiments and experimental and observational field studies. Seedlings appeared in all experimental microsites in the field, corroborating phytotron predictions that gap- or depth-sensing strategies should be absent in the species. Seasonal timing patterns were predicted from a cold stratification response in the phytotron, but these were not supported in the field. The relationship between dormancy, germinability during storage, and seed carry-over in the field largely conformed to expectations. Seeds from four different geographical regions responded differently to temperature and cold stratification and storage. Dormancy and seed carry-over was higher in seeds from a coastal population, where winters are relatively mild and the probability of repeated freeze-thaw events is high, than in populations from mountain and inland areas, where winters are colder. This is discussed against two alternative hypotheses about the relationship between climate and dormancy in seasonal climates. [source] A multicentre study on eradication of Helicobacter pylori using four 1-week triple therapies in ChinaALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 1 2001CHINESE NATIONAL COOPERATIVE STUDY GROUP FOR HELICOBACTER PYLORI Background: Short-term proton pump inhibitor-based triple therapies for the eradication of Helicobacter pylori are used widely. The eradication rates vary greatly from country to country and from region to region. Aim: To assess the efficacy at eradicating H. pylori of 1-week regimens containing three medications: omeprazole (O) or colloidal bismuth subcitrate (B), furazolidone (F) or metronidazole (M), and amoxicillin (A) or clarithromycin (C). Methods: A multicentre study involving 20 hospitals in different regions of China. A total of 892 patients with H. pylori- positive non-ulcer dyspepsia or healed duodenal ulcer confirmed by endoscopy were recruited to receive, randomly, one of four regimens: OMC, OFC, OFA, and BFC, b.d. for 7 days. 13C-urea breath test was performed 4,8 weeks after completion of treatment. Results: The eradication rates with per protocol/intention-to-treat analyses were: OMC (n=217/219) 66%/65%; OFC (n=227/229) 69%/69%; OFA (n=223/225) 87%/86%; and BFC (n=214/219) 80%/78%. The eradication rate (per protocol analysis) in duodenal ulcer (79%) was higher than that in non-ulcer dyspepsia (73%, P=0.033). Patient compliance was good. The adverse events of the four regimens were mild, and mainly gastrointestinal. Conclusions: The omeprazole, furazolidine and amoxicillin regimen achieves a high H. pylori eradication rate in different geographical regions of China. [source] Geographical variation of genetic and phenotypic traits in the Mexican sailfin mollies, Poecilia velifera and P. petenensisMOLECULAR ECOLOGY, Issue 9 2008S. J. HANKISON Abstract Comparing the patterns of population divergence using both neutral genetic and phenotypic traits provides an opportunity to examine the relative importance of evolutionary mechanisms in shaping population differences. We used microsatellite markers to examine population genetic structure in the Mexican sailfin mollies Poecilia velifera and P. petenensis. We compared patterns of genetic structure and divergence to that in two types of phenotypic traits: morphological characters and mating behaviours. Populations within each species were genetically distinct, and conformed to a model of isolation by distance, with populations within different geographical regions being more genetically similar to one another than were populations from different regions. Bayesian clustering and barrier analyses provided additional support for population separation, especially between geographical regions. In contrast, none of the phenotypic traits showed any type of geographical pattern, and population divergence in these traits was uncorrelated with that found in neutral markers. There was also a weaker pattern of regional differences among geographical regions compared to neutral genetic divergence. These results suggest that while divergence in neutral traits is likely a product of population history and genetic drift, phenotypic divergence is governed by different mechanisms, such as natural and sexual selection, and arises at spatial scales independent from those of neutral markers. [source] Truth and Fiction: A Study of the Gender Gap in the US National LegislaturePOLITICS, Issue 3 2001Stephanie L. Hallett In the United States, women are generally perceived to vote more liberally than men. Analysing voting patterns from 12 US Congresses (the 94th to 105th Congress) on a range of political issues, I conduct an estimation explaining voting behaviour by gender, differences in party identification and affiliation with different geographical regions in the United States. My results indicate that women do generally vote more liberally than men, but this difference can be attributed to differences in party identification and regional representation more than to gender differences. [source] Conservation education in Madagascar: three case studies in the biologically diverse island-continent,AMERICAN JOURNAL OF PRIMATOLOGY, Issue 5 2010Francine L. Dolins Abstract Few Malagasy children and adults are aware of the rare and unique fauna and flora indigenous to their island-continent, including flagship lemur species. Even the Malagasy ancestral proverbs never mentioned lemurs, but these same proverbs talked about the now extinct hippopotamus. Madagascar's geography, history, and economic constraints contribute to severe biodiversity loss. Deforestation on Madagascar is reported to be over 100,000 ha/year, with only 10,15% of the island retaining natural forest [Green & Sussman, 1990]. Educating children, teacher-training, and community projects about environmental and conservation efforts to protect the remaining natural habitats of endangered lemur species provide a basis for long-term changes in attitudes and practices. Case studies of three conservation education projects located in different geographical regions of Madagascar, Centre ValBio, Madagacar Wildlife Conservation Alaotra Comic Book Project, and The Ako Book Project, are presented together with their ongoing stages of development, assessment, and outcomes. We argue that while nongovernmental organizational efforts are and will be very important, the Ministry of Education urgently needs to incorporate biodiversity education in the curriculum at all levels, from primary school to university. Am. J. Primatol. 72:391,406, 2010. © 2009 Wiley-Liss, Inc. [source] | |||||||||||||