987 resultados para HUMAN COOPERATION


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Editorial remarks.-- Open discussion: Tariff policies for the achievement of MDGs ; Natural resources within UNASUR ; The human right to water and sanitation.-- Meetings: Tariff and Regulatory Policies ; Transboundary Water Cooperation ; Latinosan III.-- News of the Network: National Water Resources Strategy ; Hydroelectric Development in Chile.-- Internet and WWW News

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Cooperation between individuals is an important requisite for the maintenance of social relationships. The purpose of this study was to investigate cooperation in children in the school environment, where individuals could cooperate or not with their classmates in a public goods game. We investigated which of the following variables influenced cooperation in children: sex, group size, and information on the number of sessions. Group size was the only factor to significantly affect cooperation, with small-group children cooperating significantly more than those in large groups. Both sex and information had no effect on cooperation. We suggest that these results reflect the fact that, in small groups, individuals were more efficient in controlling and retaliating theirs peers than in large groups. (C) 2008 Elsevier Inc. All rights reserved.

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The DOK1 gene is a putative tumour suppressor gene located on the human chromosome 2p13 which is frequently rearranged in leukaemia and other human tumours. We previously reported that the DOK1 gene can be mutated and its expression down-regulated in human malignancies. However, the mechanism underlying DOK1 silencing remains largely unknown. We show here that unscheduled silencing of DOK1 expression through aberrant hypermethylation is a frequent event in a variety of human malignancies. DOK1 was found to be silenced in nine head and neck cancer (HNC) cell lines studied and DOK1 CpG hypermethylation correlated with loss of gene expression in these cells. DOK1 expression could be restored via demethylating treatment using 5-aza-2'deoxycytidine. In addition, transduction of cancer cell lines with DOK1 impaired their proliferation, consistent with the critical role of epigenetic silencing of DOK1 in the development and maintenance of malignant cells. We further observed that DOK1 hypermethylation occurs frequently in a variety of primary human neoplasm including solid tumours (93% in HNC, 81% in lung cancer) and haematopoietic malignancy (64% in Burkitt's lymphoma). Control blood samples and exfoliated mouth epithelial cells from healthy individuals showed a low level of DOK1 methylation, suggesting that DOK1 hypermethylation is a tumour specific event. Finally, an inverse correlation was observed between the level of DOK1 gene methylation and its expression in tumour and adjacent non tumour tissues. Thus, hypermethylation of DOK1 is a potentially critical event in human carcinogenesis, and may be a potential cancer biomarker and an attractive target for epigenetic-based therapy.

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Trade in non-timber forest products (NTFPs) has been touted as promoting forest conservation and enhancing the well-being of local residents through increased cash income, which is considered a positive outcome. However, research on cooperation has demonstrated that increased market access and income may strengthen or weaken cooperation. Because cooperation is essential for community resilience in small-scale societies, negative effects on people's well-being can be expected if increased NTFP trade reduces cooperation. To evaluate whether NTFP trade affected cooperation, we used household data (survey and systematic observations) to compare the frequency of cooperation in two communities of Brazilian Amazon Caboclos, one of which engaged in NTFP trade, while the other did not. Cooperation was less frequent in the community trading NTFPs, but neither household cash income nor household participation in NTFP exploitation was associated with cooperative behavior. Decreased frequency most likely derived from indirect effects of NTFP trade, such as less time to fish or socialize, or other outcomes observable only at the community level, such as income inequality, the influx of new residents and consequent population growth. Our results indicate that conservation and development projects based on NTFP trade may negatively impact social and economic well-being of local communities.

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The femicide in Ciudad Juárez is a story made of extreme violence against women for different reasons, by different actors, under different circumstances, and following different behavioural patterns. All within a gender discrimination frame based on the idea that women are inferior, interchangeable and disposable according to the patriarchal hierarchy still present in Mexico, but strongly reinforced by a sort of conspiracy of silence provoked either by the high impunity rate, the governmental incompetence to solve the crimes, or the general indifference of the population. It is the story of hundreds of kidnapped, raped, in many cases tortured, and murdered young women in the border between Mexico and the United States. The murders first came into light in 1993 and up to now young women continue to “disappear” without any hope of bringing the perpetrators to justice, stopping impunity, convicting the assassins, and bringing justice to the families of the deceased girls and women. The main questions about femicide in Ciudad Juárez seem to be: why were they brutally assassinated?, why most of the crimes have not been solved yet?, why and how is Ciudad Juárez different from other border cities with the same characteristics?, which powers are behind those crimes in a city that implies mainly women as its labor force, and which has the lowest unemployment rate in the whole country? But there are also many other questions dealing more with the context, the Juarences’ lifestyles, the eventual hidden powers behind the crimes, the possible murderers’ reasons, the response of the local civil society, or the international community actions to fight against femicide there, among many other things, that are still waiting for an answer and that this paper will ‘narrate’ in order to provide a holistic panorama for the readers. But above all there is the need to remember that every single woman or girl assassinated there had a name, an identity, a family, a story to be told time after time and as many times as necessary, in order to avoid accepting these crimes just as statistics, as cold numbers that might make us forget the human tragedy that has been flagellating the city since 1993. We must remember as well that their deaths express gender oppression, the inequality of the relations between what is male and what is female, a manifestation of domination, terror, social extermination, patriarchal hegemony, social class and impunity. The city is the perfect mirror where all the contradictions of globalization get reflected. It is there where all the globalization evils are present and survive by sucking their women’s blood. It is a city where some concepts such as gender, migration and power are closely related with a negative connotation.

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The times following international or civil conflicts but also violent revolutions often come with unequal share of the peace dividend for men and women. Delusions for women who gained freedom of movement and of roles during conflict but had to step back during reconstruction and peace have been recorded in all regions of the world. The emergence of peacebuilding as a modality for the international community to ensure peace and security has slowly incorporated gender sensitivity at the level of legal and policy instruments. Focusing on Rwanda, a country that has obtained significant gender advancement in the years after the genocide while also obtaining to not relapse into conflict, this research explores to what extent the international community has contributed to this transformation. From a review of evaluations, findings are that many of the interventions did not purse gender equality, and overall the majority understood gender and designed actions is a quite superficial way which would hardly account for the significative advancement in combating gender discrimination that the Government, for its inner political will, is conducting. Then, after a critique from a feminist standpoint to the concept of human security, departing from the assumption (sustained by the Governemnt of Rwanda as well) that domestic violence is a variable influencing level of security relevant at the national level, a review of available secondary data on GBV is conducted an trends over the years analysed. The emerging trends signal a steep increase in prevalence of GBV and in domestic violence in particular. Although no conclusive interpretation can be formulated on these data, there are elements suggesting the increase might be due to augmented reporting. The research concludes outlining possible further research pathways to better understand the link in Rwanda between the changing gender norms and the GBV.

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Background Although evolutionary models of cooperation build on the intuition that costs of the donor and benefits to the receiver are the most general fundamental parameters, it is largely unknown how they affect the decision of animals to cooperate with an unrelated social partner. Here we test experimentally whether costs to the donor and need of the receiver decide about the amount of help provided by unrelated rats in an iterated prisoner's dilemma game. Results Fourteen unrelated Norway rats were alternately presented to a cooperative or defective partner for whom they could provide food via a mechanical apparatus. Direct costs for this task and the need of the receiver were manipulated in two separate experiments. Rats provided more food to cooperative partners than to defectors (direct reciprocity). The propensity to discriminate between helpful and non-helpful social partners was contingent on costs: An experimentally increased resistance in one Newton steps to pull food for the social partner reduced the help provided to defectors more strongly than the help returned to cooperators. Furthermore, test rats provided more help to hungry receivers that were light or in poor condition, which might suggest empathy, whereas this relationship was inverse when experimental partners were satiated. Conclusions In a prisoner's dilemma situation rats seem to take effect of own costs and potential benefits to a receiver when deciding about helping a social partner, which confirms the predictions of reciprocal cooperation. Thus, factors that had been believed to be largely confined to human social behaviour apparently influence the behaviour of other social animals as well, despite widespread scepticism. Therefore our results shed new light on the biological basis of reciprocity.

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The alpha4beta1 integrin is an essential adhesion molecule for recruitment of circulating lymphocytes into lymphoid organs and peripheral sites of inflammation. Chemokines stimulate alpha4beta1 adhesive activity allowing lymphocyte arrest on endothelium and subsequent diapedesis. Activation of the GTPase Rac by the guanine-nucleotide exchange factor Vav1 promoted by CXCL12 controls T lymphocyte adhesion mediated by alpha4beta1. In this study, we investigated the role of DOCK2, a lymphocyte guanine-nucleotide exchange factor also involved in Rac activation, in CXCL12-stimulated human T lymphocyte adhesion mediated by alpha4beta1. Using T cells transfected with DOCK2 mutant forms defective in Rac activation or with DOCK2 small interfering RNA, we demonstrate that DOCK2 is needed for efficient chemokine-stimulated lymphocyte attachment to VCAM-1 under shear stress. Flow chamber, soluble binding, and cell spreading assays identified the strengthening of alpha4beta1-VCAM-1 interaction, involving high affinity alpha4beta1 conformations, as the adhesion step mainly controlled by DOCK2 activity. The comparison of DOCK2 and Vav1 involvement in CXCL12-promoted Rac activation and alpha4beta1-dependent human T cell adhesion indicated a more prominent role of Vav1 than DOCK2. These results suggest that DOCK2-mediated signaling regulates chemokine-stimulated human T lymphocyte alpha4beta1 adhesive activity, and that cooperation with Vav1 might be required to induce sufficient Rac activation for efficient adhesion. In contrast, flow chamber experiments using lymph node and spleen T cells from DOCK2(-/-) mice revealed no significant alterations in CXCL12-promoted adhesion mediated by alpha4beta1, indicating that DOCK2 activity is dispensable for triggering of this adhesion in mouse T cells, and suggesting that Rac activation plays minor roles in this process.

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Reduced activity of 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) plays a role in essential hypertension and the sensitivity of blood pressure to dietary salt. Nonconservative mutations in the coding region are extremely rare and do not explain the variable 11beta-HSD2 activity. We focused therefore on the 5'-regulatory region and identified and characterized the first promoter polymorphisms. Transfections of variants G-209A and G-126A into SW620 cells reduced promoter activity and affinity for activators nuclear factor 1 (NF1) and Sp1. Chromatin immunoprecipitation revealed Sp1, NF1, and glucocorticoid receptor (GR) binding to the HSD11B2 promoter. Dexamethasone induced expression of mRNA and activity of HSD11B2. GR and/or NF1 overexpression increased endogenous HSD11B2 mRNA and activity. GR complexes cooperated with NF1 to activate HSD11B2, an effect diminished in the presence of the G-209A variant. When compared to salt-resistant subjects (96), salt-sensitive volunteers (54) more frequently had the G-209A variant, higher occurrence of alleles A4/A7 of polymorphic microsatellite marker, and higher urinary ratios of cortisol to cortisone metabolites. First, we conclude that the mechanism of glucocorticoid-induced HSD11B2 expression is mainly mediated by cooperation between GR and NF1 on the HSD11B2 promoter and, second, that the newly identified promoter variants reduce activity and cooperation of cognate transcription factors, resulting in diminished HSD11B2 transcription, an effect favoring salt sensitivity.

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Funded by the US-EU Atlantis Program, the International Cooperation in Ambient Computing Education Project is establishing an international knowledge-building community for developing a broader computer science curriculum aimed at preparing students for real-world problems in a multidisciplinary, global world. The project is collaboration among Troy University (USA), University of Sunderland (UK), FernUniversität in Hagen (Germany), Universidade do Algarve (Portugal), University of Arkansas at Little Rock (USA) and San Diego State University (USA). The curriculum will include aspects of social science, cognitive science, human-computer interaction, organizational studies, global studies, and particular application areas as well as core computer science subjects. Programs offered at partner institutions will form trajectories through the curriculum. A degree will be defined in terms of combinations of trajectories which will satisfy degree requirements set by accreditation organizations. This is expected to lead to joint- or dual-degree programs among the partner institutions in the future. This paper describes the goals and activities of the project and discusses implementation issues.

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Blood supply is a critical issue in most tissue engineering approaches for large defect healing. As vessel ingrowth from surrounding tissues is proven to be insufficient, current strategies are focusing on the neo-vascularisation process. In the present study, we developed an in vitro pre-vascularised construct using 3D polyurethane (PU) scaffolds, based on the association of human Endothelial Progenitor Cells (EPC, CD34+ and CD133+) with human Mesenchymal Stem Cells (MSC). We showed the formation of luminal tubular structures in the co-seeded scaffolds as early as day 7 in culture. These tubular structures were proven positive for endothelial markers von Willebrand Factor and PECAM-1. Of special significance in our constructs is the presence of CD146-positive cells, as a part of the neovasculature scaffolding. These cells, coming from the mesenchymal stem cells population (MSC or EPC-depleted MSC), also expressed other markers of pericyte cells (NG2 and αSMA) that are known to play a pivotal function in the stabilisation of newly formed pre-vascular networks. In parallel, in co-cultures, osteogenic differentiation of MSCs occurred earlier when compared to MSCs monocultures, suggesting the close cooperation between the two cell populations. The presence of angiogenic factors (from autologous platelet lysates) in association with osteogenic factors seems to be crucial for both cell populations' cooperation. These results are promising for future clinical applications, as all components (cells, growth factors) can be prepared in an autologous way.