homogenization
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- MeSH
- cestování MeSH
- dítě MeSH
- dospělí MeSH
- fagotypizace MeSH
- fágy salmonel * MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- pulzní gelová elektroforéza MeSH
- Salmonella enteritidis virologie MeSH
- salmonelóza epidemiologie mikrobiologie MeSH
- senioři MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
- Jamajka MeSH
- Kanada MeSH
- New Brunswick MeSH
- Nové Skotsko MeSH
- ostrov prince Edwarda MeSH
Island species and habitats are particularly vulnerable to human disturbances, and anthropogenic changes are increasingly overwriting natural island biogeographic patterns. However, quantitative comparisons of how native and alien assemblages respond to human disturbances are scarce. Using data from 6,242 species of vertebrates, invertebrates and plants, from 7,718 sites on 81 islands, we model how land-use change, human population density and distance to the nearest road affect local assemblages of alien and native species on islands. We found that land-use change reduces both richness and abundance of native species, whereas the number and abundance of alien species are high in plantation forests and agricultural or urban sites. In contrast to the long-established pattern for native species (i.e., decline in species number with island isolation), more isolated islands have more alien species across most land uses than do less isolated islands. We show that alien species play a major role in the turnover of island assemblages: our models show that aliens outnumber natives among the species present at disturbed sites but absent from minimally-disturbed primary vegetation. Finally, we found a homogenization pattern for both native and alien assemblages across sites within most land uses. The declines of native species on islands in the face of human pressures, and the particular proneness to invasions of the more remote islands, highlight the need to reduce the intensity of human pressures on islands and to prevent the introduction and establishment of alien species.
- MeSH
- bezobratlí růst a vývoj MeSH
- biodiverzita * MeSH
- ekosystém MeSH
- lesy MeSH
- lidé MeSH
- ostrovy * MeSH
- rostliny MeSH
- zavlečené druhy * MeSH
- zemědělství MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- ostrovy * MeSH
We provide an explorative and international comparison of the governance models of academic medical centres (AMCs). These centres face significant challenges, including disruptive external pressures and enduring financial conflicts pertaining to patient treatment, research and education. Therefore, we covered 10 European countries (Cyprus, Czechia, Denmark, Germany, Italy, Latvia, the Netherlands, Norway, Poland and Spain) and one associated state (Israel) in our analysis. In addition, we developed an expert questionnaire to collect data on the governance of AMCs in these 11 countries. Our results revealed no standardised definition of AMCs, with countries combining patient care, education/teaching and research differently. However, the ownership of such institutions is significantly homogeneous and is limited to public or private, nonprofit ownership. Furthermore, significant differences are associated with the (functional) integration level between the hospital and medical school. Therefore, most experts believe that the governance of AMCs will evolve into a more functionally integrated model of patient care, research and education.
The purpose of this research is to quantitatively compare everyday situational experience around the world. Local collaborators recruited 5,447 members of college communities in 20 countries, who provided data via a Web site in 14 languages. Using the 89 items of the Riverside Situational Q-sort (RSQ), participants described the situation they experienced the previous evening at 7:00 p.m. Correlations among the average situational profiles of each country ranged from r = .73 to r = .95; the typical situation was described as largely pleasant. Most similar were the United States/Canada; least similar were South Korea/Denmark. Japan had the most homogenous situational experience; South Korea, the least. The 15 RSQ items varying the most across countries described relatively negative aspects of situational experience; the 15 least varying items were more positive. Further analyses correlated RSQ items with national scores on six value dimensions, the Big Five traits, economic output, and population. Individualism, Neuroticism, Openness, and Gross Domestic Product yielded more significant correlations than expected by chance. Psychological research traditionally has paid more attention to the assessment of persons than of situations, a discrepancy that extends to cross-cultural psychology. The present study demonstrates how cultures vary in situational experience in psychologically meaningful ways.
- MeSH
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- osobnost * MeSH
- psychometrie statistika a číselné údaje MeSH
- Q-třídění statistika a číselné údaje MeSH
- sociální chování * MeSH
- srovnání kultur * MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Austrálie etnologie MeSH
- Čína etnologie MeSH
- Evropa etnologie MeSH
- Japonsko etnologie MeSH
- Jihoafrická republika etnologie MeSH
- Kanada etnologie MeSH
- Korejská republika etnologie MeSH
- Spojené státy americké etnologie MeSH
Here, we present a study of the population genetic architecture and microevolution of the Egyptian fruit bat (Rousettus aegyptiacus) at the environmental margins in the Middle East using mitochondrial sequences and nuclear microsatellites. In contrast to the rather homogenous population structure typical of cave-dwelling bats in climax tropical ecosystems, a relatively pronounced isolation by distance and population diversification was observed. The evolution of this pattern could be ascribed to the complicated demographic history at higher latitudes related to the range margin fragmentation and complex geomorphology of the studied area. Lineages from East Africa and Arabia show divergent positions. Within the northwestern unit, the most marked pattern of the microsatellite data set is connected with insularity, as demonstrated by the separate status of populations from Saharan oases and Cyprus. These demes also exhibit a reduction in genetic variability, which is presumably connected with founder effects, drift and other potential factors related to island evolution as site-specific selection. Genetic clustering indicates a semipermeability of the desert barriers in the Sahara and Arabian Peninsula and a corridor role of the Nile Valley. The results emphasize the role of the island environment in restricting the gene flow in megabats, which is also corroborated by biogeographic patterns within the family, and suggests the possibility of nascent island speciation on Cyprus. Demographic analyses suggest that the colonization of the region was connected to the spread of agricultural plants; therefore, the peripatric processes described above might be because of or strengthened by anthropogenic changes in the environment.
- MeSH
- Bayesova věta MeSH
- Chiroptera genetika MeSH
- genetická variace MeSH
- genotyp MeSH
- mikrosatelitní repetice MeSH
- mitochondriální DNA genetika MeSH
- molekulární evoluce * MeSH
- molekulární sekvence - údaje MeSH
- ostrovy MeSH
- populační genetika * MeSH
- sekvenční analýza DNA MeSH
- shluková analýza MeSH
- tok genů MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- ostrovy MeSH
- Střední východ MeSH
- východní Afrika MeSH
Chronic myeloid leukemia (CML) invites biologically based radiation risk modeling because CML is simultaneously well-understood, homogeneous and prevalent. CML is known to be caused by a translocation involving the ABL and BCR genes, almost all CML patients have the BCR-ABL translocation, and CML is prevalent enough that its induction is unequivocally detected among Hiroshima A-bomb survivors. In a previous paper, a linear-quadratic-exponential (LQE) dose-response model was used to estimate the lifetime excess risk of CML in the limit of low doses of gamma-rays, R gamma. This estimate assumed that BCR-ABL translocation dose-response curves in stem cells for both neutrons and gamma-rays, differ only by a common proportionality constant from dicentric aberration dose-response curves in lymphocytes. In the present paper we challenge this assumption by predicting the BCR-ABL dose response. The predictions are based on the biophysical theory of dual radiation action (TDRA) as it applies to recent BCR-to-ABL distance data in G0 human lymphocytes; this data shows BCR and ABL geometric distributions that are not uniform and not independent, with close association of the two genes in some cells. The analysis speaks against the previous proportionality assumption. We compute 11 plausible LQE estimates of R gamma, 2 based on the proportionality assumption and 9 based on TDRA predictions. For each estimate of R gamma we also compute an associated estimate of the number of CML target cells, N; the biological basis of the LQE model allows us to form such estimates. Consistency between N and hematological considerations provides a plausibility check of the risk estimates. Within the group of estimates investigated, the most plausible lifetime excess risk estimates tend to lie near R gamma = 0.01 Gy-1, substantially higher than risk estimates based on the proportionality assumption.
- MeSH
- bcr-abl fúzní proteiny * genetika MeSH
- chronická myeloidní leukemie * epidemiologie genetika MeSH
- geny abl MeSH
- hodnocení rizik MeSH
- lidé MeSH
- nukleární válka MeSH
- onkogenní proteiny genetika MeSH
- onkogeny * MeSH
- protoonkogenní proteiny c-bcr MeSH
- protoonkogenní proteiny * MeSH
- radiační leukemie * epidemiologie genetika MeSH
- rizikové faktory MeSH
- statistické modely * MeSH
- translokace genetická MeSH
- tyrosinkinasy * MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
- Research Support, U.S. Gov't, P.H.S. MeSH
- Geografické názvy
- Japonsko MeSH
- Spojené státy americké MeSH
BACKGROUND: The digenean species of Echinostoma (Echinostomatidae) with 37 collar spines that comprise the so-called 'revolutum' species complex, qualify as cryptic due to the interspecific homogeneity of characters used to differentiate species. Only five species were considered valid in the most recent revision of the group but recent molecular studies have demonstrated a higher diversity within the group. In a study of the digeneans parasitising molluscs in central and northern Europe we found that Radix auricularia, R. peregra and Stagnicola palustris were infected with larval stages of two cryptic species of the 'revolutum' complex, one resembling E. revolutum and one undescribed species, Echinostoma sp. IG. This paper provides morphological and molecular evidence for their delimitation. METHODS: Totals of 2,030 R. auricularia, 357 R. peregra and 577 S. palustris were collected in seven reservoirs of the River Ruhr catchment area in Germany and a total of 573 R. peregra was collected in five lakes in Iceland. Cercariae were examined and identified live and fixed in molecular grade ethanol for DNA isolation and in hot/cold 4% formaldehyde solution for obtaining measurements from fixed materials. Partial fragments of the mitochondrial gene nicotinamide adenine dinucleotide dehydrogenase subunit 1 (nad1) were amplified for 14 isolates. RESULTS: Detailed examination of cercarial morphology allowed us to differentiate the cercariae of the two Echinostoma spp. of the 'revolutum' species complex. A total of 14 partial nad1 sequences was generated and aligned with selected published sequences for eight species of the 'revolutum' species complex. Both NJ and BI analyses resulted in consensus trees with similar topologies in which the isolates from Europe formed strongly supported reciprocally monophyletic lineages. The analyses also provided evidence that North American isolates identified as E. revolutum represent another cryptic species of the 'revolutum' species complex. CONCLUSION: Our findings highlight the need for further analyses of patterns of interspecific variation based on molecular and morphological evidence to enhance the re-evaluation of the species and advance our understanding of the relationships within the 'revolutum' group of Echinostoma.
- MeSH
- Echinostoma anatomie a histologie klasifikace genetika izolace a purifikace MeSH
- fylogeneze MeSH
- hlemýždi parazitologie MeSH
- jezera parazitologie MeSH
- molekulární sekvence - údaje MeSH
- řeky parazitologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Island MeSH
- Německo MeSH