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81.
MARC DE HERT DAN COHEN JULIO BOBES MARCELO CETKOVICH‐BAKMAS STEFAN LEUCHT DAVID M. NDETEI JOHN W. NEWCOMER RICHARD UWAKWE ITSUO ASAI HANS‐JURGEN MÖLLER SHIV GAUTAM JOHAN DETRAUX CHRISTOPH U. CORRELL 《World psychiatry》2011,10(2):138-151
Physical disorders are, compared to the general population, more prevalent
in people with severe mental illness (SMI). Although this excess morbidity
and mortality is largely due to modifiable lifestyle risk factors, the screening
and assessment of physical health aspects remains poor, even in developed
countries. Moreover, specific patient, provider, treatment and system factors
act as barriers to the recognition and to the management of physical diseases
in people with SMI. Psychiatrists can play a pivotal role in the improvement
of the physical health of these patients by expanding their task from clinical
psychiatric care to the monitoring and treatment of crucial physical parameters.
At a system level, actions are not easy to realize, especially for developing
countries. However, at an individual level, even simple and very basic monitoring
and treatment actions, undertaken by the treating clinician, can already improve
the problem of suboptimal medical care in this population. Adhering to monitoring
and treatment guidelines will result in a substantial enhancement of physical
health outcomes. Furthermore, psychiatrists can help educate and motivate
people with SMI to address their suboptimal lifestyle, including smoking,
unhealthy diet and lack of exercise. The adoption of the recommendations presented
in this paper across health care systems throughout the world will contribute
to a significant improvement in the medical and related psychiatric health
outcomes of patients with SMI. 相似文献
82.
83.
Costs of plant defences to herbivores have been extensively studied, but costs of chemical defences to carnivores are less well understood. We examine the costs to Australian keelback snakes (Tropidonophis mairii, Gray 1841) of consuming cane toads (Bufo[Rhinella]marinus Linnaeus 1758). Cane toads (an invasive species in Australia) are highly toxic. Although keelbacks can consume toads without dying (unlike most Australian snakes), we show that cane toads are poor quality prey for keelbacks. Toads are of low net nutritional value, take longer to consume than do native frogs and reduce the snake's locomotor performance for up to 6 h after ingestion of a meal. These latter effects may increase a snake's vulnerability to predation. Nutritional content of vertebrate prey is not the only factor driving the evolution of foraging behaviour; other more subtle costs, such as risk of predation, may be widespread. 相似文献
84.
PATRIZIA FERRANTE CHRISTOPHER R. CLARKE KERI A. CAVANAUGH RICHARD W. MICHELMORE ROBERTO BUONAURIO BORIS A. VINATZER 《Molecular Plant Pathology》2009,10(6):837-842
To study the role of type III-secreted effectors in the host adaptation of the tobacco ( Nicotiana sp.) pathogen Pseudomonas syringae pv. tabaci , a selection of seven strains was first characterized by multilocus sequence typing (MLST) to determine their phylogenetic affinity. MLST revealed that all strains represented a tight phylogenetic group and that the most closely related strain with a completely sequenced genome was the bean ( Phaseolus vulgaris ) pathogen P. syringae pv. phaseolicola 1448A. Using primers designed to 21 P. syringae pv. phaseolicola 1448A effector genes, it was determined that P. syringae pv. phaseolicola 1448A shared at least 10 effectors with all tested P. syringae pv. tabaci strains. Six of the 11 effectors that failed to amplify from P. syringae pv. tabaci strains were individually expressed in one P. syringae pv. tabaci strain. Although five effectors had no effect on phenotype, growth in planta and disease severity of the transgenic P. syringae pv. tabaci expressing hopQ1-1 Pph1448A were significantly increased in bean, but reduced in tobacco. We conclude that hopQ1-1 has been retained in P. syringae pv. phaseolicola 1448A, as this effector suppresses immunity in bean, whereas hopQ1-1 is missing from P. syringae pv. tabaci strains because it triggers defences in Nicotiana spp. This provides evidence that fine-tuning effector repertoires during host adaptation lead to a concomitant reduction in virulence in non-host species. 相似文献
85.
Ecosystem feedbacks and cascade processes: understanding their role in the responses of Arctic and alpine ecosystems to environmental change 总被引:3,自引:0,他引:3
PHILIP A. WOOKEY RIEN AERTS† RICHARD D. BARDGETT‡ FLORENCE BAPTIST§ KARI ANNE BRÅTHEN¶ JOHANNES H. C. CORNELISSEN† LAURA GOUGH IAIN P. HARTLEY DAVID W. HOPKINS SANDRA LAVOREL§ GAIUS R. SHAVER†† 《Global Change Biology》2009,15(5):1153-1172
Global environmental change, related to climate change and the deposition of airborne N‐containing contaminants, has already resulted in shifts in plant community composition among plant functional types in Arctic and temperate alpine regions. In this paper, we review how key ecosystem processes will be altered by these transformations, the complex biological cascades and feedbacks that might result, and some of the potential broader consequences for the earth system. Firstly, we consider how patterns of growth and allocation, and nutrient uptake, will be altered by the shifts in plant dominance. The ways in which these changes may disproportionately affect the consumer communities, and rates of decomposition, are then discussed. We show that the occurrence of a broad spectrum of plant growth forms in these regions (from cryptogams to deciduous and evergreen dwarf shrubs, graminoids and forbs), together with hypothesized low functional redundancy, will mean that shifts in plant dominance result in a complex series of biotic cascades, couplings and feedbacks which are supplemental to the direct responses of ecosystem components to the primary global change drivers. The nature of these complex interactions is highlighted using the example of the climate‐driven increase in shrub cover in low‐Arctic tundra, and the contrasting transformations in plant functional composition in mid‐latitude alpine systems. Finally, the potential effects of the transformations on ecosystem properties and processes that link with the earth system are reviewed. We conclude that the effects of global change on these ecosystems, and potential climate‐change feedbacks, cannot be predicted from simple empirical relationships between processes and driving variables. Rather, the effects of changes in species distributions and dominances on key ecosystem processes and properties must also be considered, based upon best estimates of the trajectories of key transformations, their magnitude and rates of change. 相似文献
86.
Sources of plant-derived carbon and stability of organic matter in soil: implications for global change 总被引:2,自引:0,他引:2
SUSAN E. CROW KATE LAJTHA TIMOTHY R. FILLEY† CHRISTOPHER W. SWANSTON‡ RICHARD D. BOWDEN§ BRUCE A. CALDWELL 《Global Change Biology》2009,15(8):2003-2019
Alterations in forest productivity and changes in the relative proportion of above‐ and belowground biomass may have nonlinear effects on soil organic matter (SOM) storage. To study the influence of plant litter inputs on SOM accumulation, the Detritus Input Removal and Transfer (DIRT) Experiment continuously alters above‐ and belowground plant inputs to soil by a combination of trenching, screening, and litter addition. Here, we used biogeochemical indicators [i.e., cupric oxide extractable lignin‐derived phenols and suberin/cutin‐derived substituted fatty acids (SFA)] to identify the dominant sources of plant biopolymers in SOM and various measures [i.e., soil density fractionation, laboratory incubation, and radiocarbon‐based mean residence time (MRT)] to assess the stability of SOM in two contrasting forests within the DIRT Experiment: an aggrading deciduous forest and an old‐growth coniferous forest. In the deciduous forest, removal of both above‐ and belowground inputs increased the total amount of SFA over threefold compared with the control, and shifted the SFA signature towards a root‐dominated source. Concurrently, light fraction MRT increased by 101 years and C mineralization during incubation decreased compared with the control. Together, these data suggest that root‐derived aliphatic compounds are a source of SOM with greater relative stability than leaf inputs at this site. In the coniferous forest, roots were an important source of soil lignin‐derived phenols but needle‐derived, rather than root‐derived, aliphatic compounds were preferentially preserved in soil. Fresh wood additions elevated the amount of soil C recovered as light fraction material but also elevated mineralization during incubation compared with other DIRT treatments, suggesting that not all of the added soil C is directly stabilized. Aboveground needle litter additions, which are more N‐rich than wood debris, resulted in accelerated mineralization of previously stored soil carbon. In summary, our work demonstrates that the dominant plant sources of SOM differed substantially between forest types. Furthermore, inputs to and losses from soil C pools likely will not be altered uniformly by changes in litter input rates. 相似文献
87.
HERVE MULARD † THIERRY AUBIN JOËL F. WHITE ‡ RICHARD H. WAGNER ÉTIENNE DANCHIN 《Biological journal of the Linnean Society. Linnean Society of London》2009,97(2):289-297
Acoustic features are important for individual and species recognition. However, while dialectal variations in song characteristics have been described in many songbirds, geographical divergence in vocal features across populations has seldom been studied in birds that are not thought to have song-learning abilities. Here, we document marked differences in the vocal structure of calls of two populations of black-legged kittiwakes ( Rissa tridactyla ), a seabird whose call is considered as not being learned from other individuals. We found that calls vary both within and between populations. Within-population variation may convey individual identity, whereas the marked differences in frequency and temporal parameters observed between the two populations may reveal ongoing divergence among kittiwake populations. Moreover, we were unable to detect any sex signature in adult calls in a Pacific population (Middleton, Alaska), while these were detected in an Atlantic population (Hornøya, Norway), potentially affecting sexual behaviours. Despite the fact that these calls seemed to change over the reproductive season and across years, the individual signature remained fairly stable. Such vocal differences suggest that Pacific and Atlantic populations may be undergoing behavioural divergences that may reveal early stages of speciation, as is suggested by molecular data. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 289–297. 相似文献
88.
NINA ROTHE ANDREW J. GOODAY TOMAS CEDHAGEN JOSÉ FAHRNI J. ALAN HUGHES ANTON PAGE RICHARD B. PEARCE JAN PAWLOWSKI 《Zoological Journal of the Linnean Society》2009,157(3):451-469
We describe three new species of the genus Gromia from bathyal and abyssal depths in the Weddell Sea. The new species are characterized by a combination of morphological and molecular criteria. All three species possess a distinct oral capsule and a layer of ‘honeycomb membranes’, which form the inner part of the organic test wall. Both these features are typical of gromiids. Their identification as gromiids is confirmed by analyses of partial small subunit ribosomal DNA (SSU rDNA) gene sequences. Gromia marmorea sp. nov. is a rounded species with a prominent oral capsule and a characteristically mottled appearance. In Gromia melinus sp. nov. , the test surface exhibits a polygonal pattern of ridges, with a layer of clay particles coating the surface between the ridges. Gromia winnetoui sp. nov. represents an elongate morphotype in which the organic test is enclosed within an agglutinated case, a feature previously unknown in gromiids. Phylogenetic analysis using the maximum‐likelihood method revealed that all three species form distinct clades, reflecting the morphological differences among Weddell Sea species, as well as between deep‐water Southern Ocean Gromia and previously described gromiids. © 2009 The Linnean Society of London, Zoological Journal of the Linnean Society, 2009, 157 , 451–469. 相似文献
89.
LAURA A. KAMMIN PATRICK D. HUBERT RICHARD E. WARNER PHILIP C. MANKIN 《The Journal of wildlife management》2009,73(6):973-979
ABSTRACT State wildlife agencies commonly offer private landowners cost-share and technical assistance to improve habitat, but the cost-effectiveness and long-term outcomes of these efforts are rarely evaluated. In 1998, we began a 3-part, statewide evaluation of the Illinois Department of Natural Resources’ (IDNR; USA) Private Land Wildlife Habitat Management Program (hereafter the program) as it functioned from 1986 to 1996. We sent a mail-back questionnaire to IDNR biologists to collect information on their perceptions of the program. We sent a separate mail-back questionnaire to private landholders who participated in the program to ascertain their demographic profile, motivations for participation, and attitudes regarding the program. We also conducted on-site evaluations of private properties that were managed under the guidance of the program. We conducted our study to 1) assess if the program effectively assisted participants in establishing and maintaining wildlife habitat, and 2) determine factors associated with optimal management of wildlife habitat on private lands to refine the program and improve effectiveness. We found significant differences between participants in their land use priorities and motivations for managing wildlife and in the resources available to participants to establish and maintain habitat. Our results indicate that although financial incentives may increase participation in private lands initiatives, improving technical and material assistance to landholders is essential for maintaining quality wildlife habitat over the long-term. 相似文献
90.
History and evolution of alpine plants endemic to the Qinghai-Tibetan Plateau: Aconitum gymnandrum (Ranunculaceae) 总被引:1,自引:0,他引:1
LIUYANG WANG† RICHARD J. ABBOTT‡ WEI ZHENG† PING CHEN† YUJIN WANG JIANQUAN LIU 《Molecular ecology》2009,18(4):709-721
How Quaternary climatic oscillations affected range distributions and intraspecific divergence of alpine plants on the Qinghai‐Tibetan Plateau (QTP) remains largely unknown. Here, we report a survey of chloroplast DNA (cpDNA) and nuclear ribosomal internal transcribed spacer (ITS) DNA variation aimed at exploring the phylogeographical history of the QTP alpine endemic Aconitum gymnandrum. We sequenced three cpDNA fragments (rpl20–rps12 intergenic spacer, the trnV intron and psbA‐trnH spacer) and also the nuclear (ITS) region in 245 individuals from 23 populations sampled throughout the species’ range. Two distinct lineages, with eastern and western geographical distributions respectively, were identified from a phylogenetic analysis of ITS sequence variation. Based on a fast substitution rate, these were estimated to have diverged from each other in the early Pleistocene approximately 1.45 Ma. The analysis of cpDNA variation identified nine chlorotypes that clustered into two major clades that were broadly congruent in geographical distribution with the two ITS lineages. The east–west split of cpDNA divergence was supported by an amova which partitioned approximately half of the total variance between these two groups of populations. Analysis of the spatial distribution of chlorotypes showed that each clade was subdivided into two groups of populations such that a total of four population groups existed in the species. It is suggested that these different groups derive from four independent glacial refugia that existed during the Last Glacial Maximum (LGM), and that three of these refugia were located at high altitude on the QTP platform itself at that time. Coalescent simulation of chlorotype genealogies supported both an early Pleistocene origin of the two main cpDNA clades and also the ‘four‐refugia’ hypothesis during the LGM. Two previous phylogeographical studies of QTP alpine plants indicated that such plants retreated to refugia at the eastern/south‐eastern plateau edge during the LGM and/or previous glacial maxima. However, the results for A. gymnandrum suggest that at least some of these cold‐tolerant species may have also survived centrally on the QTP platform throughout the Quaternary. 相似文献