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Theoretical Link (theoretical + link)
Selected AbstractsTHEORETICAL LINKS BETWEEN KANT AND CONFUCIANISM: PRELIMINARY REMARKSJOURNAL OF CHINESE PHILOSOPHY, Issue 1 2006Article first published online: 21 FEB 200, CHUNG-YING CHENG [source] Helicobacter pylori CagA: Analysis of Sequence Diversity in Relation to Phosphorylation Motifs and Implications for the Role of CagA as a Virulence FactorHELICOBACTER, Issue 3 2001Doyle J. Evans Jr Abstract CagA is transported into host target cells and subsequently phosphorylated. Clearly this is a mechanism by which Helicobacter pylori could take control of one or more host cell signal transduction pathways. Presumably the end result of this interaction favors survival of H. pylori, irrespective of eventual damage to the host cell. CagA is noted for its amino acid (AA) sequence diversity, both within and outside the variable region of the molecule. The primary purpose of this review is to examine how variation in the type and number of CagA phosphorylation sites might determine the outcome of infection by different strains of H. pylori. The answer to this question could help to explain the widely disparate results obtained when H. pylori CagA status has been compared to type and severity of disease outcome in different populations, that is in different countries. Analysis of all available CagA sequences revealed that CagA contains both tyrosine phosphorylation motifs (TPMs) and cyclic-AMP-dependent phosphorylation motifs (CPMs). There are two potential CPMs near the N-terminus of CagA and at least two in the repeat region; these are not all equally well conserved. We also defined a 48-residue AA sequence, which includes the N-terminal TPM at tyrosine (Y)-122, which distinguishes between Eastern (Hong Kong-Taiwan-Japan-Thailand) H. pylori isolates and those from the West (Europe-Africa-the Americas-Australia). All 28 of the Eastern type CagA proteins have a functional N-terminal TPM whereas 11 of 47 (23.4%) of the Western type contain an inactive motif, with threonine (T) replacing the critical aspartic acid (D) residue. Only 13 of 24 (54%) known CagA sequences have an active TPM in the repeat region and only one has two TPMs in this region. The potential TPM near the C-terminus of CagA is not likely to be important since only 3 of 24 (12.5%) sequences were found to be intact. Protein database searches revealed that the AA sequence immediately following the TPM at Y-122 in CagA is homologous with a pair of PDZ domains which are common in signal transducing proteins, particularly tyrosine phosphatases. This provides a theoretical link between CagA and many of the observed responses of host cells to H. pylori. In summary, not all CagA proteins are equal in their potential for initiating host cell responses via signal transduction pathways. The degree of functional diversity of this protein depends upon which phosphorylation motifs are critical to the biological activity of CagA. [source] Mating preferences, sexual selection and patterns of cladogenesis in ray-finned fishesJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 2 2007J. E. MANK Abstract Evolutionary theory predicts that sexual selection may increase taxonomic diversity when emergent mating preferences result in reproductive isolation and therefore speciation. This theory has been invoked to explain patterns of diversity in ray-finned fishes (most notably in the cichlids), but the theory has not been tested comparatively in fish. Additionally, several other unrelated factors have been identified as promoters of cladogenesis, so it is unclear how important sexual selection might be in diversification. Using sister-clade analysis, I tested the relationship between the presence of sexually selected traits and taxonomic diversification in actinopterygiian fishes, a large clade that shows substantial diversity in mating preferences and related sexually selected traits. In all identified sister-families that differed with regard to the proportion of species manifesting sexually selected traits, sexual selection was correlated with increased diversification, and this association was significant across all sister clades (P = 0.02). This suggests that sexual selection, when present, is a substantial driver of diversification in the ray-finned fishes, and lends further empirical support to the theoretical link between mating preferences and accelerated cladogenesis. [source] Nurse Home Visits to Maternal,Child Clients: A Review of Intervention ResearchPUBLIC HEALTH NURSING, Issue 3 2004Diane B. McNaughton Ph.D. Abstract Home visiting has been considered a promising strategy for addressing the multiple needs of families at risk. Research reviews are a valuable resource for researchers, policymakers, and practitioners who develop and support new home-visiting interventions. This review examines 13 research studies published between the years of 1980 and 2000 that test the effectiveness of home-visiting interventions using professional nurses as home visitors. Findings indicate that a wide range of client problems are addressed during home visits using a variety of nursing interventions. Missing from most of the reports is a clear theoretical link between the client problem addressed, the nursing intervention, and target outcomes. About half of the studies were successful in achieving desired outcomes. Future research should be directed by middle-range practice theory, clearly explicate the nursing intervention being tested, use power analysis to determine sample size, and report reliability and validity of dependent variable measures with culturally diverse samples. [source] Contemporary issues and future directions for research into pathological gamblingADDICTION, Issue 8 2000Article first published online: 2 SEP 200 The recent healthy increase in research into all aspects of gambling is noted. The dominant theme accounting for most of this research is the mental disorder model of pathological gambling and measures that have been derived from this conceptualization. It is suggested that an alternative approach focusing on the construct of choice or subjective control over gambling may be a research direction that will ensure that progress is maintained. In this paper a context for the discussion is provided by first identifying briefly fundamental conceptual and methodological issues associated with the mental disorder model. In particular it is argued that the heterogeneity of the diagnosis of pathological gambling makes the research task of assessing truly independent variables extremely difficult. Subsequently an illustrative schema is presented that demonstrates both the potential advantages and some of the complexities associated with the dependent variable of self-control over gambling behaviour. The main advantages are argued to be (a) the focus of research is narrowed to one potential cause of harmful impacts rather than the great diversity of impacts themselves, (b) prospective studies of regular gamblers in real gambling venues may be a key source of insight into the development of pathological gambling and (c) it promotes the development of theoretical links with the mainstream of the discipline of psychology. Despite the conceptual difficulties that may be associated with the variable of self-control, it is suggested that these may be overcome because contemporary research into the addictive behaviours has demonstrated considerable success in the definition and measurement of control and related themes such as craving, restraint and temptation. [source] Motility: mobility as capitalINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 4 2004Vincent Kaufmann Social and territorial structures form intricate relations that transcend a social stratification or spatial focus. Territorial features and geographic displacements are structuring principles for society, as societal features and social change effect the structure and use of territory. Based on our examination of the conceptual and theoretical links between spatial and social mobility, we propose a concept that represents a new form of inequality. Termed ,motility', this construct describes the potential and actual capacity of goods, information or people to be mobile both geographically and socially. Three major features of motility , access, competence and appropriation , are introduced. In this article, we focus on conceptual and theoretical contributions of motility. In addition, we suggest a number of possible empirical investigations. Motility presents us with an innovative perspective on societal changes without prematurely committing researchers to work within structuralist or postmodern perspectives. More generally, we propose to revisit the fluidification debate in the social sciences with a battery of questions that do not begin and end with whether or not society is in flux. Instead, we introduce a field of research that takes advantage of the insights from competing paradigms in order to reveal the social dynamics and consequences of displacements in geographic and social space. Les structures sociales et territoriales forment des relations complexes qui dépassent toute stratification sociale ou convergence spatiale. Les caractéristiques territoriales et déplacements géographiques sont, pour la société, des principes structurants, tout comme les caractéristiques sociétales et le changement social font naître la structure et l'usage d'un territoire. A partir d'un examen des liens conceptuels et théoriques entre les mobilités spatiale et sociale, cet article propose un concept traduisant une nouvelle forme d'inégalité: appelé,motilité', il décrit le potentiel et l'aptitude réelle des marchandises, informations ou individus àêtre mobiles sur un plan tant géographique que social. Trois traits essentiels de la motilité, accès, compétence et appropriation , sont présentés. Si l'article s'attache aux contributions conceptuelles et théoriques de la motilité, il suggère aussi plusieurs axes possibles d'études empiriques. La motilité offre une perspective novatrice sur les changements sociétaux, sans engager prématurément les travaux de recherches sur des rails structuralistes ou post-modernes. Plus généralement, il s'agit de revisiter le débat sur la fluidification en sciences sociales à l'aide d'une batterie de questions qui, ni au début ni à la fin, ne demande si la société est fluctuante ou non. En revanche, l'article propose un domaine de recherches qui exploite les réflexions tirées de paradigmes concurrents afin de révéler la dynamique sociale et les conséquences des déplacements dans l'espace géographique et social. [source] | |||||||||||||