955 resultados para Differentiated socialization


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During differentiation in vitro, embryonic stem (ES) cells generate progenitors for most hemato-lymphoid lineages. We studied the developmental potential of two ES cell subpopulations that share the fetal stem cell antigen AA4.1 but differ in expression of the lymphoid marker B220 (CD45R). Upon transfer into lymphoid deficient mice, the B220+ population generated a single transient wave of IgM+ IgD+ B cells but failed to generate T cells. In contrast, transfer of the B220− fraction achieved long-term repopulation of both T and B lymphoid compartments and restored humoral and cell-mediated immune reactions in the recipients. To assess the hemato-lymphopoietic potential of ES cell subsets in comparison to their physiological counterparts, cotransplantation experiments with phenotypically homologous subsets of fetal liver cells were performed, revealing a more potent developmental capacity of the latter. The results suggest that multipotential and lineage-committed lymphoid precursors are generated during in vitro differentiation of ES cells and that both subsets can undergo complete final maturation in vivo.

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We have developed a universally applicable system for conditional gene expression in embryonic stem (ES) cells that relies on tamoxifen-dependent Cre recombinase-loxP site-mediated recombination and bicistronic gene-trap expression vectors that allow transgene expression from endogenous cellular promoters. Two vectors were introduced into the genome of recipient ES cells, successively: (i) a bicistronic gene-trap vector encoding the β-galactosidase/neoR fusion protein and the Cre-ERT2 (Cre recombinase fused to a mutated ligand-binding domain of the human estrogen receptor) and (ii) a bicistronic gene-trap vector encoding the hygroR protein and the human alkaline phosphatase (hAP), the expression of which is prevented by tandemly repeated stop-of-transcription sequences flanked by loxP sites. In selected clones, hAP expression was shown to be regulated accurately by 4′hydroxy-tamoxifen. Strict hormone-dependent expression of hAP was achieved (i) in vitro in undifferentiated ES cells and embryoid bodies, (ii) in vivo in virtually all the tissues of the 10-day-old chimeric fetus (after injection of 4′hydroxy-tamoxifen to foster mothers), and (iii) ex vivo in primary embryonic fibroblasts isolated from chimeric fetuses. Therefore, this approach can be applied to drive conditional expression of virtually any transgene in a large variety of cell types, both in vitro and in vivo.

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Neuroblastoma (NB), a tumor arising from the sympathetic nervous system, is one of the most common malignancies in childhood. Several recent reports on the p53 genotype found virtually exclusive wild-type status in primary tumors, and it was postulated that p53 plays no role in the development of NB. Here, however, we report that the vast majority of undifferentiated NBs exhibit abnormal cytoplasmic sequestration of wild-type p53. This inability of p53 to translocate to the nucleus presumably prevents the protein from functioning as a suppressor. Thirty of 31 cases (96%) of undifferentiated NB showed elevated levels of wild-type p53 in the cytoplasm of all tumor cells concomittant with a lack of nuclear staining. p53 immunoprecipitation from tumor tissues showed a 4.5- to 8-fold increase over normal protein levels. All of 10 tumors analyzed harbored wild-type p53 by direct sequencing of full-length cDNA and Southern blot. In addition, no MDM-2 gene amplification was seen in all 11 tumors analyzed. In contrast, no p53 abnormality was detected in 14 differentiated ganglioneuroblastomas and 1 benign ganglioneuroma. We conclude that loss of p53 function seems to play a major role in the tumorigenesis of undifferentiated NB. This tumor might abrogate the transactivating function of p53 by inhibiting its access to the nucleus, rather than by gene mutation. Importantly, our results suggest that (i) this could be a general mechanism for p53 inactivation not limited to breast cancer (where we first described it) and that (ii) it is found in a tumor previously not thought to be affected by p53 alteration.

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This dissertation engages the question of why German political elites accepted the use of force during the 1990s and started to commit the country's armed forces to multilateral peacekeeping missions. Previous governments of the Federal Republic had opposed foreign deployment of the military and Germany was characterized by a unique strategic culture in which the efficacy of military force was widely regarded as negative. The rediscovery of the use of force constituted a significant reorientation of German security policy with potentially profound implications for international relations. I use social role theory to explain Germany's security policy reorientation. I argue that political elites shared a national role conception of their country as a dependable and reliable ally. Role expectations of the international security environment changed as a result of a general shift to multilateral intervention as means to address emerging security problems after the Cold War. Germany's resistance to the use of force was viewed as inappropriate conduct for a power possessing the economic and military wherewithal of the Federal Republic. Elites from allied countries exerted social pressure to have Germany contribute commensurate with capabilities. German political elites adapted role behavior in response to external expectations in an effort to preserve the national role conception of a dependable and reliable ally. Security policy reorientation to maintain Germany's national role conception was pursued by conservative elites who acted as 'role entrepreneurs'. CDU/CSU politicians initiated a process of role adaptation to include the use of force for non-defensive missions. They persuaded Social Democrats and Alliance 90/Green party politicians that the maintenance of the country's role conception necessitated a reorientation in security policy to accommodate the changes in the security environment.

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Use of evidence-based practice is becoming more expected and necessary for mental health practitioners. This allows for proof, accountability, and rigorous standards to be upheld, facilitates healthcare reimbursement, and provides a wider range of services to more clients. Appropriate monitoring and outcome measurement is essential to determine the effectiveness of a given intervention. An organization providing group social skills interventions for children 7-18 years was analyzed to facilitate the best plan for evaluating treatment effectiveness. Measurable goals and objectives consistent with the organizations mission and values were developed. Appropriate social skills measurement tools were identified. Strengths and weaknesses of each measure were compared, and existing literature was reviewed to ensure cohesion between this evaluation and current standards in literature. Parent report, self report, and teacher report on Piers-Harris II, BASC-2, and Skills Improvement System Rating Scales were determined to be the most relevant measures of social skills development. A timeline for administration and plan for how to implement measurement and use data was suggested as well as considerations for future research.

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Purpose – This article aims to investigate whether intermediaries reduce loss aversion in the context of a high-involvement non-frequently purchased hedonic product (tourism packages). Design/methodology/approach – The study incorporates the reference-dependent model into a multinomial logit model with random parameters, which controls for heterogeneity and allows representation of different correlation patterns between non-independent alternatives. Findings – Differentiated loss aversion is found: consumers buying high-involvement non-frequently purchased hedonic products are less loss averse when using an intermediary than when dealing with each provider separately and booking their services independently. This result can be taken as identifying consumer-based added value provided by the intermediaries. Practical implications – Knowing the effect of an increase in their prices is crucial for tourism collective brands (e.g. “sun and sea”, “inland”, “green destinations”, “World Heritage destinations”). This is especially applicable nowadays on account of the fact that many destinations have lowered prices to attract tourists (although, in the future, they will have to put prices back up to their normal levels). The negative effect of raising prices can be absorbed more easily via indirect channels when compared to individual providers, as the influence of loss aversion is lower for the former than the latter. The key implication is that intermediaries can – and should – add value in competition with direct e-tailing. Originality/value – Research on loss aversion in retailing has been prolific, exclusively focused on low-involvement and frequently purchased products without distinguishing the direct or indirect character of the distribution channel. However, less is known about other types of products such as high-involvement non-frequently purchased hedonic products. This article focuses on the latter and analyzes different patterns of loss aversion in direct and indirect channels.

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Purpose – The purpose of this study is to attempt to explain why the impact of Corporate Social Responsibility (CSR) initiatives may be different and/or more important in service firms compared to manufacturing firms. CSR is becoming a common strategy, hence its extensive research. Central to it is the analysis of the effect of CSR on a firm’s performance, whose outcome depends on firm-specific and industry-related factors. Design/methodology/approach – The event study methodology is applied to all the 248 companies that have ever traded on the Spanish Stock Market between 1990 and 2007. A regression analysis examines potential different effects of CSR on service and goods firms. Findings – The results show that CSR activities have a positive impact on firm performance that is higher for service firms than for manufacturing firms. Actions related to the environment, responsible labor relationships and good corporate governance are especially important in the service context. Research limitations/implications – This research is focused on shareholders’ performance, but it does not consider other stakeholders, such as real consumer behavior or employees’ commitment and productivity. Practical implications – Service firms are likely to gain from focusing on some CSR activities (environment, employees and good corporate governance) and should use their responsible behavior as a valuable tool for public relations and differentiation in the market. Originality/value – This article is the first attempt to empirically test and explain why the relationship between CSR and firm performance may be different (more positive) for service vs manufacturing firms.

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In a context of intense competition, cooperative advertising between firms is critical. Accordingly, the objective of this article is to analyze the potential differentiated effect of advertising on two basic consumption patterns: individual products (i.e. hotel, restaurant) vs. bundle (i.e. hotel + restaurant). This research adds to the extant literature in that, for the first time, this potential differentiated effect is examined through a hierarchical modelling framework that reflects the way people make their decisions: first, they decide whether to visit or not a region; second, whether to purchase an advertised product in that region; and third, whether to buy products together or separately at the region. The empirical analysis, applied to a sample of 11,288 individuals, shows that the influence of advertising is positive for the decisions to visit and to purchase; however, when it comes to the joint or separate consumption, advertising has a differentiated effect: its impact is much greater on the joint alternative (“hotel + restaurant”) than the separate options (“hotel” and “restaurant”). Also, the variable distance moderates the advertising effect.

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Flexibility might be convenient when it comes to accommodating member states’ differing socio-economic and political interests in an expanding EU. Yet, opt-outs, enhanced cooperation and cooperation between member states outside the EU’s legal framework are calling into question the boundaries of this constitutional, institutional and legal differentiation in an EU that is founded on common principles, with a specific legal order and common institutions.

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Differentiated Europe can be analysed in terms of the three meta-challenges outlined in this publication – stagnation, fragmentation and legitimacy. My argument is simple: stagnation or the prospect of it has been a catalyst for differentiation, fragmentation poses a risk of differentiation gone too far and legitimacy of differentiation is embedded on institutional cohesion and good results.

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This paper conceptualizes the European Union (EU) as a system of differentiated integration characterized by both variation in levels of centralization (vertical differentiation) and variation in territorial extension (horizontal differentiation) across policy areas. Differentiation has been a concomitant of deepening and widening and has increased and consolidated as the EU’s powers, policy scope, and membership have grown. Turning to explanation, the paper attributes the pattern of differentiated integration in the EU to the interaction of interdependence and politicization. Differentiation among the member states (internal differentiation) results from supranational integration under conditions of high interdependence and politicization. By contrast, external differentiation (the selective policy integration of non-member states) occurs in highly interdependent but weakly politicized policy areas. These constellations are illustrated in case studies of differentiation in the internal market, monetary union, and defence.

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The August war in 2008 between Russia and Georgia caught the world by surprise but nevertheless brought the European Union (EU) to the forefront of the international efforts to end the hostilities, and the EU became the leading international actor involved with the conflict resolution process. However, in the years following the armed conflict, the conflict resolution process lost pace, and the impact of the EU beyond the immediate aftermath of the August 2008 war has been put into question. By undertaking a qualitative case study, this paper aims to explore to what extent the EU has impacted on the conflict resolution process of Georgia’s secessionist conflicts in 2008-2015. It will argue that the EU’s policies have only to a limited extent impacted on this conflict resolution process, which can be related to the objectives, priorities and time perspectives of the EU’s conflict resolution policies. The EU’s efforts have significantly contributed to the objective of conflict prevention, but the profile of the EU in the field of international conflict management weakened its position in the area of conflict transformation, where the lack of progress in turn limited the EU’s impact in the areas of international conflict management and conflict settlement. The main conclusion put forward is that in order to have a true impact, the EU needs to undertake a differentiated, balanced and patient approach to conflict resolution.