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GRAHAM THORNICROFT ATALAY ALEM RENATO ANTUNES DOS SANTOS ELIZABETH BARLEY ROBERT E. DRAKE GUILHERME GREGORIO CHARLOTTE HANLON HIROTO ITO ERIC LATIMER ANN LAW JAIR MARI PETER McGEORGE RAMACHANDRAN PADMAVATI DENISE RAZZOUK MAYA SEMRAU YUTARO SETOYA RANGASWAMY THARA DAWIT WONDIMAGEGN 《World psychiatry》2010,9(2):67-77
This paper provides guidance on the steps, obstacles and mistakes to avoid
in the implementation of community mental health care. The document is intended
to be of practical use and interest to psychiatrists worldwide regarding the
development of community mental health care for adults with mental illness.
The main recommendations are presented in relation to: the need for coordinated
policies, plans and programmes, the requirement to scale up services for whole
populations, the importance of promoting community awareness about mental
illness to increase levels of help-seeking, the need to establish effective
financial and budgetary provisions to directly support services provided in
the community. The paper concludes by setting out a series of lessons learned
from the accumulated practice of community mental health care to date worldwide,
with a particular focus on the social and governmental measures that are required
at the national level, the key steps to take in the organization of the local
mental health system, lessons learned by professionals and practitioners,
and how to most effectively harness the experience of users, families, and
other advocates. 相似文献
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1. The bivalve Dreissena polymorpha has invaded many freshwater ecosystems worldwide in recent decades. Because of their high fecundity and ability to settle on almost any solid substratum, zebra mussels usually outcompete the resident species and cause severe damage to waterworks. Time series of D. polymorpha densities display a variety of dynamical patterns, including very irregular behaviours. Unfortunately, there is a lack of mathematical modelling that could explain these patterns. 2. Here, we propose a very simple discrete‐time population model with age structure and density dependence that can generate realistic dynamics. Most of the model parameters can be derived from existing data on D. polymorpha. Some of them are quite variable: with respect to these we perform a sensitivity analysis of the model behaviour and verify that non‐equilibrial regimes (either periodic or chaotic) are the rule rather than the exception. 3. Even in circumstances where the model dynamics are aperiodic it is possible to predict total density peaks from previous peaks. This turns out to be true also in the presence of environmental stochasticity. 4. Using the stochastic model we explore the effects of age‐selective predation. Quite surprisingly, larger removal rates of adults do not always result in smaller population densities and mussel biomasses. Moreover, non‐selective predation can result in skewed size‐frequency distributions which, therefore, are not necessarily the footprint of predators’ preference for larger or smaller zebra mussels. 相似文献
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JAANA HIETALA CAMILLA LAURÉN-MÄÄTTÄ & MARI WALLS 《The Plant journal : for cell and molecular biology》2004,37(2):299-306
1. We studied the effects of both acute and chronic exposure of Daphnia pulex to toxic Microcystis aeruginosa . We focused on the effects of Daphnia genotype and temperature (19 and 24 °C).
2. The study revealed variation among ten Daphnia pulex clones in survivorship under acute Microcystis exposure, measured as EC50 . An increase in temperature caused a clear decrease in EC50 , although the ranking of clones according to sensitivity remained the same at both temperatures.
3. In the chronic exposure of two of the clones, toxic Microcystis reduced survival and reproduction. The two clones differed in their responses, indicating different means of coping with toxic cyanobacteria. Toxic cyanobacteria reduced slightly more at 24 °C than 19 °C.
4. The clonal difference in sensitivity to toxic cyanobacteria at acute exposure was reversed at chronic exposure. This indicates that the results from short-term toxicity cannot be used to predict life history responses under sublethal exposure. 相似文献
2. The study revealed variation among ten Daphnia pulex clones in survivorship under acute Microcystis exposure, measured as EC
3. In the chronic exposure of two of the clones, toxic Microcystis reduced survival and reproduction. The two clones differed in their responses, indicating different means of coping with toxic cyanobacteria. Toxic cyanobacteria reduced slightly more at 24 °C than 19 °C.
4. The clonal difference in sensitivity to toxic cyanobacteria at acute exposure was reversed at chronic exposure. This indicates that the results from short-term toxicity cannot be used to predict life history responses under sublethal exposure. 相似文献
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R. VALADE M. KENIS† A. HERNANDEZ-LOPEZ S. AUGUSTIN N. MARI MENA E. MAGNOUX R. ROUGERIE‡ F. LAKATOS§ A. ROQUES C. LOPEZ-VAAMONDE 《Molecular ecology》2009,18(16):3458-3470
Biological invasions usually start with a small number of founder individuals. These founders are likely to represent a small fraction of the total genetic diversity found in the source population. Our study set out to trace genetically the geographical origin of the horse-chestnut leafminer, Cameraria ohridella , an invasive microlepidopteran whose area of origin is still unkown. Since its discovery in Macedonia 25 years ago, this insect has experienced an explosive westward range expansion, progressively colonizing all of Central and Western Europe. We used cytochrome oxidase I sequences (DNA barcode fragment) and a set of six polymorphic microsatellites to assess the genetic variability of C. ohridella populations, and to test the hypothesis that C. ohridella derives from the southern Balkans (Albania, Macedonia and Greece). Analysis of mtDNA of 486 individuals from 88 localities allowed us to identify 25 geographically structured haplotypes. In addition, 480 individuals from 16 populations from Europe and the southern Balkans were genotyped for 6 polymorphic microsatellite loci. High haplotype diversity and low measures of nucleotide diversities including a significantly negative Tajima's D indicate that C. ohridella has experienced rapid population expansion during its dispersal across Europe. Both mtDNA and microsatellites show a reduction in genetic diversity of C. ohridella populations sampled from artificial habitats (e.g. planted trees in public parks, gardens, along roads in urban or sub-urban areas) across Europe compared with C. ohridella sampled in natural stands of horse-chestnuts in the southern Balkans. These findings suggest that European populations of C. ohridella may indeed derive from the southern Balkans. 相似文献
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MARI METTE TOLLEFSRUD ROY KISSLING FELIX GUGERLI ØYSTEIN JOHNSEN TORE SKRØPPA RACHID CHEDDADI W. O. VAN DER KNAAP MAŁGORZATA LATAŁOWA RUTH TERHÜRNE‐BERSON THOMAS LITT THOMAS GEBUREK CHRISTIAN BROCHMANN CHRISTOPH SPERISEN 《Molecular ecology》2008,17(18):4134-4150
Norway spruce (Picea abies [L.] Karst.) is a broadly distributed European conifer tree whose history has been intensively studied by means of fossil records to infer the location of full‐glacial refugia and the main routes of postglacial colonization. Here we use recently compiled fossil pollen data as a template to examine how past demographic events have influenced the species’ modern genetic diversity. Variation was assessed in the mitochondrial nad1 gene containing two minisatellite regions. Among the 369 populations (4876 trees) assayed, 28 mitochondrial variants were identified. The patterns of population subdivision superimposed on interpolated fossil pollen distributions indicate that survival in separate refugia and postglacial colonization has led to significant structuring of genetic variation in the southern range of the species. The populations in the northern range, on the other hand, showed a shallow genetic structure consistent with the fossil pollen data, suggesting that the vast northern range was colonized from a single refugium. Although the genetic diversity decreased away from the putative refugia, there were large differences between different colonization routes. In the Alps, the diversity decreased over short distances, probably as a result of population bottlenecks caused by the presence of competing tree species. In northern Europe, the diversity was maintained across large areas, corroborating fossil pollen data in suggesting that colonization took place at high population densities. The genetic diversity increased north of the Carpathians, probably as a result of admixture of expanding populations from two separate refugia. 相似文献
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ARNE A. ANDERBERG MARI KÄLLERSJÖ 《Botanical journal of the Linnean Society. Linnean Society of London》1988,96(4):323-332
l position of Oedera L. (Compositae). The South African genus Oedera L. (Compositae-Anthemideae) is shown to be closely related to the South African genera Relhania and Leysera . A transfer of Oedera from the tribe Anthemideae to the tribe Inuleae is proposed. Several synapomorphies, like a two-layered sexine, concave leaves, pappus of connate scales, long and slender cypselas define the monophyletic group. The pollen-wall morphology of Oedera is described and the chromosome number 2 n = 14 is reported. 相似文献
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When the mosses Pleurozium schreberi (Brid.) Mitt, and Ceratodon purpureus (Hedw) Brid. were exposed for 4 week to either continuous or rhythmie light of 75 or 150 μE m?2 s?1, the photosynthetic rate, calculated on the basis of chlorophyll and of dry weight, was lower in the moss plants exposed to continuous light. RUBP-carboxylase activity was lower in these plants, too. On the other hand more starch was accumulated in the chloroplasts in continuous than in rhythmic light. Neither moss species showed any differences in the dark respiration rates. The chlorophyll content was lower in continuous light, especially at the higher intensity; but Chi a/Chl b ratio showed little change compared with that in rhythmic light. The reduction of chlorophyll did not affect the two chlorophyll protein complexes equally; the percentage of chlorophyll associated with CP I decreased, while that associated with CP II showed liltle change. The decrease in CP I chlorophyll appeared to be due to the partial destruction of stroma thylakoids: the size or the grana increased in continuous light. Many of the effects of continuous light in these mosses resembled those observed in higher plants in the early phases of senescence. 相似文献
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