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1.
Community indicators have been a frequent focus of the scholarly literature. There has been little exploration, however, in relation to rural communities, especially in developing countries. This reflects the special challenges associated with the complexity of rural systems, and the difficulties involved in developing appropriate and systemic indicators for rural communities. Identifying indicators that help the community to monitor progress towards sustainable outcomes requires a framework that is both practical and holistic. This paper introduces a participatory systemic framework for identifying community indicators, which respects the principles of complexity and honours the sense of ownership present in the communities. This framework is an iterative, sharing, co-learning engagement process that extends from creating a shared vision and extracting its core messages, to identifying indicators of progress and determining what actions to try. Importantly, this framework enables us to rank the indicators identified by communities with reference to ‘leverage points’, the best places to intervene in the social-environmental system for transformational change. This framework provides a potential pathway for sustainable rural development and perhaps also for organisations and urban communities.  相似文献   
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The mosquito-borne malaria parasite Plasmodium falciparum kills an estimated 0.7-2.7 million people every year, primarily children in sub-Saharan Africa. Without effective interventions, a variety of factors-including the spread of parasites resistant to antimalarial drugs and the increasing insecticide resistance of mosquitoes-may cause the number of malaria cases to double over the next two decades. To stimulate basic research and facilitate the development of new drugs and vaccines, the genome of Plasmodium falciparum clone 3D7 has been sequenced using a chromosome-by-chromosome shotgun strategy. We report here the nucleotide sequences of chromosomes 10, 11 and 14, and a re-analysis of the chromosome 2 sequence. These chromosomes represent about 35% of the 23-megabase P. falciparum genome.  相似文献   
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Disease proteomics   总被引:56,自引:0,他引:56  
Hanash S 《Nature》2003,422(6928):226-232
The sequencing of the human genome and that of numerous pathogens has opened the door for proteomics by providing a sequence-based framework for mining proteomes. As a result, there is intense interest in applying proteomics to foster a better understanding of disease processes, develop new biomarkers for diagnosis and early detection of disease, and accelerate drug development. This interest creates numerous opportunities as well as challenges to meet the needs for high sensitivity and high throughput required for disease-related investigations.  相似文献   
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Summary The action potential in amphibian sciatic nerve in vitro has been reported to be abolished by the topical application ofLathyrus sativus seed extract. We have confirmed this effect, but find that it is probably caused by the high K+ content of such seed extracts and that organic neurotoxins are not implicated.Acknowledgments. We thank the Wellcome Trust for financial support, Professor M.W. Bradbury for help with the ion determinations and Miss M.B. Burbridge of the Tropical Products Institute, London, for obtaining seed from Bombay, India.  相似文献   
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Reversible effect of an inhalational anaesthetic on lymphocyte motility   总被引:2,自引:0,他引:2  
J F Nunn  J A Sharp  K L Kimball 《Nature》1970,226(5240):85-86
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When people move around in their environment, spatial updating, which is an automatic cognitive process, is essential to ensuring people can keep track of their relations between them and the surrounding objects, and to "recalculating" the relative position and orientation of those objects with regard to the current position of the persons. Despite the facilitating effect of spatial updating to people’s mental representation in most circumstances as demonstrated in most of the existing literature, the effect sometimes can be adversarial. For instance, some research suggested that even though people were asked to ignore their locomotion, it is difficult to suppress updating of the spatial representation during movement. The current two studies were conducted to systematically investigate the dual effects of spatial updating in both real and virtual environments. We used a typical spatial updating paradigm to explore the effects of scene familiarity (familiar vs. novel) and person’s locomotion (stationary vs. moving) on change detection accuracy (target object moved or not). The results indicated a facilitating effect of spatial updating in the novel scene condition, but an adversarial effect in the familiar scene condition-the dual effects, in both real and virtual environments.  相似文献   
10.
Qi HH  Ongusaha PP  Myllyharju J  Cheng D  Pakkanen O  Shi Y  Lee SW  Peng J  Shi Y 《Nature》2008,455(7211):421-424
Human Argonaute (Ago) proteins are essential components of the RNA-induced silencing complexes (RISCs). Argonaute 2 (Ago2) has a P-element-induced wimpy testis (PIWI) domain, which folds like RNase H and is responsible for target RNA cleavage in RNA interference. Proteins such as Dicer, TRBP, MOV10, RHA, RCK/p54 and KIAA1093 associate with Ago proteins and participate in small RNA processing, RISC loading and localization of Ago proteins in the cytoplasmic messenger RNA processing bodies. However, mechanisms that regulate RNA interference remain obscure. Here we report physical interactions between Ago2 and the alpha-(P4H-alpha(I)) and beta-(P4H-beta) subunits of the type I collagen prolyl-4-hydroxylase (C-P4H(I)). Mass spectrometric analysis identified hydroxylation of the endogenous Ago2 at proline 700. In vitro, both Ago2 and Ago4 seem to be more efficiently hydroxylated than Ago1 and Ago3 by recombinant human C-P4H(I). Importantly, human cells depleted of P4H-alpha(I) or P4H-beta by short hairpin RNA and P4H-alpha(I) null mouse embryonic fibroblast cells showed reduced stability of Ago2 and impaired short interfering RNA programmed RISC activity. Furthermore, mutation of proline 700 to alanine also resulted in destabilization of Ago2, thus linking Ago2 P700 and hydroxylation at this residue to its stability regulation. These findings identify hydroxylation as a post-translational modification important for Ago2 stability and effective RNA interference.  相似文献   
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