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At least 19 recordsLinked to original sources

PubMed2002

Regulation, consultation and divergent community views: the case of access to ART by lesbian and single women.

In the many countries which have some form of regulation of ART, a public consultation of some sort is a frequent feature of either the process leading up to regulation or of the regulatory mechanism itself. Not surprisingly, widely divergent views on the moral and political acceptability of ART are expressed during such consultations. And while such diversity of opinion is to be expected, and some even argue welcomed, in pluralist liberal democratic societies, it is often unclear how these divergent community views are and ought to be fed into the opinion-forming and decision-making processes of governments or the bodies that advise them. This article discusses first why regulation of ART may be justified, even when there is radical moral disagreement in the community, and why public consultations should play a central role in the work that advisory bodies undertake in making regulatory recommendations to government. Then, it both proposes and justifies a method for dealing with the contradictory moral views expressed by interested parties during the consultation process. To illustrate this method, the example of the attempt by single and lesbian women to access donor insemination services and ART is used.

Attitude to Health↗

PubMed2005

Phylogenetic analysis of ecomorphological divergence, community structure, and diversification rates in dusky salamanders (Plethodontidae: Desmognathus).

An important dimension of adaptive radiation is the degree to which diversification rates fluctuate or remain constant through time. Focusing on plethodontid salamanders of the genus Desmognathus, we present a novel synthetic analysis of phylogeographic history, rates of ecomorphological evolution and species accumulation, and community assembly in an adaptive radiation. Dusky salamanders are highly variable in life history, body size, and ecology, with many endemic lineages in the southern Appalachian Highlands of eastern North America. Our results show that life-history evolution had important consequences for the buildup of plethodontid-salamander species richness and phenotypic disparity in eastern North America, a global hot spot of salamander biodiversity. The origin of Desmognathus species with aquatic larvae was followed by a high rate of lineage accumulation, which then gradually decreased toward the present time. The peak period of lineage accumulation in the group coincides with evolutionary partitioning of lineages with aquatic larvae into seepage, stream-edge, and stream microhabitats. Phylogenetic simulations demonstrate a strong correlation between morphology and microhabitat ecology independent of phylogenetic effects and suggest that ecomorphological changes are concentrated early in the radiation of Desmognathus. Deep phylogeographic fragmentation within many codistributed ecomorph clades suggests long-term persistence of ecomorphological features and stability of endemic lineages and communities through multiple climatic cycles. Phylogenetic analyses of community structure show that ecomorphological divergence promotes the coexistence of lineages and that repeated, independent evolution of microhabitat-associated ecomorphs has a limited role in the evolutionary assembly of Desmognathus communities. Comparing and contrasting our results to other adaptive radiations having different biogeographic histories, our results suggest that rates of diversification during adaptive radiation are intimately linked to the degree to which community structure persists over evolutionary time.

Adaptation, Biological↗

PubMed2004

Comparison of two-stage thermophilic (68 degrees C/55 degrees C) anaerobic digestion with one-stage thermophilic (55 degrees C) digestion of cattle manure.

A two-stage 68 degrees C/55 degrees C anaerobic degradation process for treatment of cattle manure was studied. In batch experiments, an increase of the specific methane yield, ranging from 24% to 56%, was obtained when cattle manure and its fractions (fibers and liquid) were pretreated at 68 degrees C for periods of 36, 108, and 168 h, and subsequently digested at 55 degrees C. In a lab-scale experiment, the performance of a two-stage reactor system, consisting of a digester operating at 68 degrees C with a hydraulic retention time (HRT) of 3 days, connected to a 55 degrees C reactor with 12-day HRT, was compared with a conventional single-stage reactor running at 55 degrees C with 15-days HRT. When an organic loading of 3 g volatile solids (VS) per liter per day was applied, the two-stage setup had a 6% to 8% higher specific methane yield and a 9% more effective VS-removal than the conventional single-stage reactor. The 68 degrees C reactor generated 7% to 9% of the total amount of methane of the two-stage system and maintained a volatile fatty acids (VFA) concentration of 4.0 to 4.4 g acetate per liter. Population size and activity of aceticlastic methanogens, syntrophic bacteria, and hydrolytic/fermentative bacteria were significantly lower in the 68 degrees C reactor than in the 55 degrees C reactors. The density levels of methanogens utilizing H2/CO2 or formate were, however, in the same range for all reactors, although the degradation of these substrates was significantly lower in the 68 degrees C reactor than in the 55 degrees C reactors. Temporal temperature gradient electrophoresis profiles (TTGE) of the 68 degrees C reactor demonstrated a stable bacterial community along with a less divergent community of archaeal species.

Animals↗

PubMed2005

Biogeography of bacteria associated with the marine sponge Cymbastela concentrica.

Recent debate regarding microbial biogeography has focused largely on free-living microbes, yet those microbes associated with host organisms are also of interest from a biogeographical perspective. Marine eukaryotes and associated bacteria should provide ideal systems in which to consider microbial biogeography, as (i) bacteria in seawater should be able to disperse among individuals of the same host species, yet (ii) potential for adaptation to particular hosts (and thus speciation) also exists. We used 16S rDNA-DGGE (denaturing gradient gel electrophoresis) to examine geographic variability in bacterial community composition in the marine sponge Cymbastela concentrica. Denaturing gradient gel electrophoresis banding patterns (and phylogenetic analysis of excised DGGE bands) indicated different communities in Cymbastela concentrica from tropical versus temperate Australia. In contrast, communities were very similar over a 500-km portion of the sponge's temperate range. Variation in bacterial community composition was also considered with respect to ocean current patterns. We speculate that the divergent communities in different parts of the sponge's range provide evidence of endemism attributed to host association, although variation in environmental factors such as light and temperature could also explain the observed results. Interestingly, bacterial communities in seawater varied much less between tropical and temperate locations than did those in C. concentrica, supporting the concept of widespread dispersal among these free-living microbes.

Animals↗

PubMedDate not supplied

Changes in family formation among Turkish and Moroccan women in Belgium.

"This paper addresses the extent to which the behaviour of migrants...diverges from the pattern observed in the country of origin and converges on that of the country of destination.... In the first part of the analysis we compare the family formation patterns of Turks and Moroccans living in Flanders and Brussels with the patterns of Belgians living in the same regions on the one hand and with the populations of Turkey and Morocco on the other hand. In the second part we look in more detail at the behaviour of Turks and Moroccans in Belgium, distinguishing between the first and the second generation. To what extent, if any, do the immigrant communities diverge from the countries of origin on various aspects of family formation behaviour, and to what extent is there convergence with the patterns observed for Belgians?" (SUMMARY IN ITA AND FRE)

Africa↗

PubMed2007

Contribution of divergent thinking to community functioning in schizophrenia.

Fluency deficits have been associated with poor community functioning in patients with schizophrenia. In our previous study we demonstrated that the ability to generate higher-quality responses on tasks of divergent thinking as measured by several fluency tests was impaired in patients with schizophrenia. The purpose of the present study was to investigate the contribution of the deficits in divergent thinking to community dysfunction in schizophrenia. Forty Japanese outpatients with schizophrenia and 32 healthy control subjects were recruited for this study and assessed over a broad spectrum of the neurocognitive domain. Their capacity for divergent thinking was assessed by idea, design, and word fluency tests. Community functioning was assessed by using the Global Assessment of Functioning (GAF), the Life Assessment Scale for the Mentally Ill (LASMI), and the Social Functioning Scale (SFS). The results confirmed the qualitative deficits of divergent thinking in schizophrenia. Stepwise multiple regressions using neurocognitive and demographic/clinical variables as predictors revealed that the higher-quality response scores on the tasks of divergent thinking significantly contributed to community functioning. Moreover, the deficit on the verbal task of divergent thinking significantly contributed to impairment in the area of daily living, and the deficit on the nonverbal task of divergent thinking significantly contributed to impairment in the area of interpersonal relations. The results of this study reveal the importance and the possibility of cognitive remediation and cognitive training with strategies that target capacity for divergent thinking to improve community functioning in patients with schizophrenia.

Adult↗

PubMed2005

Insights in the pathogenic potential of Propionibacterium acnes from its complete genome.

One of the long-lasting open questions in understanding acne is the role of the skin bacterium Propionibacterium acnes. Opinions within the scientific community diverge regarding the importance of this Gram-positive bacterium not only in acne but also in other P. acnes-associated diseases. The recently decoded genome gives us some clues with respect to its pathogenic potential and its strategies to survive in the harsh environment of human skin. This review focuses on the major findings of the genome sequence. Special attention has been drawn to the cell surface composition of P. acnes, its antigenic potential, and to enzymes that are potentially involved in degrading skin-derived substances.

Acne Vulgaris↗

PubMed2006

Effects of reproduction norms on contraception practice among Muslim women in Amman, Jordan.

Based on the authors' interview survey for 275 Muslim women of an ethnically divergent community in Amman, Jordan, this study examined the psychosocial effects of reproduction norms on contraception practice, using the normative interpretations of legal provisions in Islam (hukm). The categorical principal component analysis (CATPCA) reduced the eight items regarding family planning and contraception use to two factors, i.e. the pressures of childbearing and acceptability of contraception use, accounting for 55% of the total variance. Even though the majority of the female subjects were conservative rather than innovative in terms of reproduction norms and significant interrelations were observed between their reproduction norms and contraception practice, approximately 70% of the female subjects who were closely in consonance with the normative interpretations of their religious leader had used contraception. It is thus indicated that religious leaders may play significant roles in increase of contraception practice among Muslim women.

Adolescent↗

PubMed2004

The influence of settling time on the formation of aerobic granules.

Aerobic granular sludge, without the addition of carrier material, has only been reported in one suspended growth system, the Sequencing Batch Reactor (SBR) operated with short fill and settling periods. Recent studies have demonstrated that extracellular polysaccharides increased with the formation of aerobic granules, and that the shear force may stimulate production of these polysaccharides. In the study described herein, two SBRs were operated with the same shear force (air flow rate 275 L h(-1)) and two different settling times (2 and 10 min). Only the reactor with 2 min settling formed completely granular sludge, although granules were present in both reactors. Community analysis using 16S rRNA PCR products and DGGE showed that the communities diverged quickly after reactor start-up. For samples taken at steady-state, the granular population was more stable and less diverse than the flocculent reactor. EPS extraction of samples using cation exchange resin yielded similar values for aerobic granular sludge and previously reported anaerobic granules. While differences in the protein and TOC content between the flocculent and granular reactors increased appreciably as the sludge became more granular, the protein to polysaccharide ratio was relatively constant. The experiment confirmed previous theories that short settling times in SBRs select for granular sludge. The settling time results in granular sludge having a higher EPS protein content and a less diverse but more stable population.

Bacteria, Aerobic↗

PubMed1993

Health in the central and eastern countries of the WHO European Region: an overview.

The enormous social, political and economic changes that began in the CCEE/NIS in the late 1980s included the revelation and public discussion of a widening health gap between these countries and the other Member States of the European Region. The continuing economic problems and their effects on health increase the urgency of the need for assistance from the international community. Diverging trends in life expectancy became evident in the mid-1970s, and the gap continued to widen in the 1980s for all major causes of death, particularly cardiovascular diseases. The situation is worse in the NIS than in the CCEE, and worst in the central Asian countries. In 1990, the worst infant mortality rate in these countries was eight times the best rate elsewhere in the Region. Non-mortality data, while patchy, confirm the indications given by mortality data. There is no single reason for the health gap, but contributory factors include the increasing prevalence of major risk factors in lifestyles and the environment, and the low efficiency and effectiveness of health care systems. The current situation and short-term prospects are mixed, but the negative trends in mortality and morbidity patterns are likely to continue for some time. While the worst health problems of the transition period in the CCEE/NIS could largely have been avoided, there is no doubt that economizing on health today will exact large costs tomorrow.

Europe↗

PubMed2005

Effects of long-term benzene pollution on bacterial diversity and community structure in groundwater.

In this study we analysed the relationship between bacterial community structures and geochemistry of groundwater in a sandstone aquifer (SIReN site) impacted mainly by BTEX hydrocarbons (benzene, toluene, ethylbenzene and xylenes), of which benzene is most abundant. The long-term presence of benzene reduced bacterial diversity: in groundwaters contaminated with more than 1.8 x 10(4) microg l(-1) of benzene, bacterial diversity was half of that in clean groundwaters. Terminal restriction fragment length polymorphism (T-RFLP) analysis of 16S rDNA revealed that the community structures were very similar in uncontaminated groundwaters, whereas communities subjected to long-term benzene contamination were different, not only from uncontaminated groundwater communities, but also from each other. Canonical correspondence analysis of the community profiles and the geochemical data showed that this divergence in community structure was not primarily caused by the direct toxic or stressful effects of benzene, but by the environmental changes brought about by benzene metabolism, in particular a decrease in redox potential.

Bacteria↗

PubMed1999

Ordination of zooplankton community data to detect pesticide effects in pond enclosures

Trends in community structure of crustacean zooplankton among 17 forest pond enclosures (5 m x 5 m x 1 m deep) were examined and analyzed to determine effects of two candidate forest pesticides. Eight enclosures were treated at two concentrations of an experimental insecticide, tebufenozide; five were treated at two concentrations of a biological herbicide, bialaphos; and four served as controls. Zooplankton community structure was characterized by ordination of species assemblages using principle components analysis (PCA) and correspondence analysis (CA). Two-dimensional plots of the first two axes from PCA and CA were constructed to explore temporal and treatment-related patterns in community structure. The first four axes of both ordination functions were used as multivariate descriptors of community structure and were examined for differences among treatments by ANOVA. Species ordination plots and sorted rotated factor loadings provided objective means of identifying the species important in determining divergence in community structure. These were considered indicator species and were examined for differences among treatments by ANOVA and specified contrasts. The ordination and subsequent analysis revealed trends in community structure and sample differences that indicated clear, concentration-dependent effects of bialaphos and equivocal effects of tebufenozide.

Journal Article↗

PubMed1997

Molecular phylogeny of Archaea from soil.

Cultivation methods have contributed to our present knowledge about the presence and diversity of microbes in naturally occurring communities. However, it is well established that only a small fraction of prokaryotes have been cultivated by standard methods and, therefore, the prokaryotes that are cultivated may not reflect the composition and diversity within those communities. Of the two prokaryotic phylogenetic domains, Bacteria and Archaea, members of the former have been shown to be ubiquitous in nature, with ample evidence of vast assemblages of uncultured organisms. There is also now increasingly compelling evidence that the Archaea, which were once thought to occupy a limited number of environments, are also globally widespread. Here we report the use of molecular phylogenetic techniques, which are independent of microbial cultivation, to conduct an assessment of Archaea in a soil microbial community. Small subunit ribosomal RNA genes of Archaea were amplified from soil and cloned. Phylogenetic and nucleotide signature analyses of these cloned small subunit ribosomal RNA gene sequences revealed a cluster of Archaea from a soil microbial community that diverge deeply from the crenarchaeotal line of descent and has the closest affiliation to the lineage of planktonic Archaea. The identification and phylogenetic classification of this archaeal lineage from soil contributes to our understanding of the ecological significance of Archaea as a component of microbial communities in non-extreme environments.

Archaea↗

PubMedDate not supplied

[Social participation in health. An experience in Simojovel, Chiapas].

One of the basic foundations for the operation of health programs is the social participation of the population in actions going from planning to evaluation, promotion and control of actions related with their own health. In the work, we present the results of a preliminary and partial evaluation of an ongoing autopromoting health project in the communities of Lázaro Cárdenas and Las Limas, in the Municipality of Simojovel, Chiapas, México. The basic goal of this work is to identify factors derived from the relations of localities with the State and, on the other hand, from socioeconomic conditions of the populations, which favor or hinder the development of social participation in their own health projects. This is a comparative study, type before and after, within and between localities, intended to measure the effect of a health program with community participation in two communities having divergent relations with the State. For this, we carried out a socioeconomic and prevalent morbidity survey before and after the implementation of social participation in health actions. We also characterized social participation in health actions and identified the type of State intervention in the localities through governmental programs and institutions. The results convey the notion that the health program contributes to enhance hygienic sanitary conditions of the population and decrease the frequency of such ailments as diarrhea and parasitic diseases; social participation is more active in Lázaro Cárdenas than in Las Limas. State interventions in the communities are given through social programs and institutions in a mandatory way, with no opportunity for community participation in decision-making. The conclusion is that the demographic organization of the community and autopromotion favor the participation in health actions, while the presence of the State through political repression and actions delivered through social programs promote dependence and paternalism, hindering the ample social participation in actions for health.

Adolescent↗

PubMed2026

Characteristics and assembly mechanisms of tobacco-associated bacteria in typical tobacco-planting regions across China.

INTRODUCTION: Plant-associated microbiota critically modulates host growth and environmental adaptation, yet assembly mechanisms, niche differentiation, and ecological strategies of bacterial communities inhabiting tobacco microhabitats remain poorly elucidated across geographical gradients. METHODS: Here, we systematically characterized bacterial microbiome assembly across five tobacco-associated niches (bulk soil, rhizosphere soil, root, stem, and leaf) from seven typical tobacco-planting regions using 16S rRNA amplicon sequencing, genome annotation, and niche breadth analysis. The independent and interactive effects of geographical location and host compartment on community structure, and further compared genomic traits, functional profiles, and life-history strategies between specialist and generalist bacterial populations were quantified. RESULTS: The results revealed a deterministic soil-plant continuum stratification of bacterial communities and diversity, with progressively simplified communities and decreasing alpha diversity from bulk soil to above-ground tissues, accompanied by progressive dominance of Proteobacteria. Geographical factors predominantly structured soil microbial communities via divergent edaphic properties, while host filtering acted as a universal dominant driver shaping endophytic microbiome assembly. Niche differentiation analysis demonstrated that niche-specialized bacterial ASVs overwhelmingly dominated all microhabitats and geographical sites, whereas generalist taxa only constituted auxiliary populations. Although specialist and generalist microbes exhibited highly conserved core genomic architectures and overall functional repertoires, they displayed distinct niche-specific functional divergence in metabolic pathways, stress resistance, and secondary metabolism across host compartments. Life-history strategy analysis further revealed that Y-strategist represented the core adaptive bacterial population, especially enriched in above-ground tobacco tissues. DISCUSSION: Our study establishes a hierarchical dual-filtering assembly model for tobacco microbiota, clarifies the ecological differentiation and functional adaptation of specialist and generalist bacteria, and provides fundamental insights into the assembly rules and adaptive mechanisms of crop-associated microbiomes for future microbial resource utilization and agricultural microbiome regulation.

biogeography↗

PubMed2004

Extended bioremediation of PAH/PCP contaminated soils from the POPILE wood treatment facility.

A study was conducted using two pilot-scale land-treatment units (LTUs) to evaluate the efficacy of different cultivation and maintenance schedules during bioremediation of contaminated soil from a wood treatment facility using landfarming technology. The soil contained high concentrations of polycyclic aromatic hydrocarbons (PAHs, approximately 13000 ppm) as well as of pentachlorophenol (PCP, approximately 1500 ppm). An initial 6-month intensive-treatment phase was followed by 24 months of less-intensive treatment. During the first phase, traditional landfarming practice of regular cultivation was compared with a gas-phase composition based cultivation strategy, and both the landfarming units were intensively monitored and maintained with respect to moisture control and delivery of nutrients. The two strategies resulted in similar contaminant concentration profiles with time during this phase, although different microbial populations developed in the two-landfarming units. The second (less-intensive) treatment phase involved no moisture control and nutrient delivery beyond the initial adjustments, and compared natural attenuation (no cultivation) with quarterly cultivation of soil. Both the strategies showed similar behavior again. GC/MS analysis of the soil samples showed PAH removal including four-ring homologues. Leachability tests at zero time and after 6 and 22 months of operation showed significant reductions in leaching of PCP and low molecular weight PAHs. Extended treatment resulted in some leaching of high molecular weight PAHs. Significant biological activity was demonstrated, even at the high contaminant concentrations. Phospholipid ester-linked fatty acid (PLFA) analysis showed an increase in biomass and a divergence in community composition in soils depending on the treatment conducted.

Biodegradation, Environmental↗

PubMed2004

Bioethics in pluralistic societies.

Contemporary liberal democracies contain multiple cultural, religious, and philosophical traditions. Within these societies, different interpretive communities provide divergent models for understanding health, illness, and moral obligations. Bioethicists commonly draw upon models of moral reasoning that presume the existence of shared moral intuitions. Principlist bioethics, case-based models of moral deliberation, intuitionist frameworks, and cost-benefit analyses all emphasise the uniformity of moral reasoning. However, religious and cultural differences challenge assumptions about common modes of moral deliberation. Too often, bioethicists minimize or ignore the existence of multiple traditions of moral inquiry. Careful consideration of the presence of multiple horizons for moral deliberation generates challenging questions about the capacity of bioethicists to effectively resolve complex cases and social policy disputes.

Bioethics↗

PubMed2025

The role of stochasticity in fungal community assembly: explaining apparent stochasticity with field experiments.

Stochasticity is a main process in community assembly. However, experimental studies rarely target stochasticity in natural communities, and hence experimental validation of stochasticity estimates in observational studies is lacking. Here, we combine experimental and observational data to unravel the role of stochasticity in the assembly of wood-inhabiting fungi. We carried out a replicated field experiment where the natural colonization of a focal fungal species was simulated through inoculation, and the local fungal communities were monitored through DNA metabarcoding before and after the inoculations. The amount of stochasticity in fungal colonization was less pronounced than expected from the amount of unpredictability in observational data, suggesting that stochasticity may play a smaller role in fungal occurrence than previously anticipated, or that it may be a stronger influence in the dispersal and establishment phases than in colonization per se. Stochasticity was more prominent in the initial phase of community succession, with the earliest successional stage involving a higher level of stochasticity than the later stage after 2 years. We conclude that experimentally measuring the role of stochasticity in community assembly is feasible for species-rich communities under natural conditions and highlight the importance of experimentally testing the accuracy of stochasticity estimates based on observational data.

Stochastic Processes↗