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Important Research Area (important + research_area)
Selected AbstractsVariation in leaf functional trait values within and across individuals and species: an example from a Costa Rican dry forestFUNCTIONAL ECOLOGY, Issue 1 2010Catherine M. Hulshof Summary 1.,Patterns of species co-existence and species diversity in plant communities remain an important research area despite over a century of intensive scrutiny. To provide mechanistic insight into the rules governing plant species co-existence and diversity, plant community ecologists are increasingly quantifying functional trait values for the species found in a wide range of communities. 2.,Despite the promise of a quantitative functional trait approach to plant community ecology, we suggest that, along with examining trait variation across species, an assessment of trait variation within species should also be a key component of a trait-based approach to community ecology. Variability within and between individuals and populations is likely widespread due to plastic responses to highly localized abiotic and biotic interactions. 3.,In this study, we quantify leaf trait variation within and across ten co-existing tree species in a dry tropical forest in Costa Rica to ask: (i) whether the majority of trait variation is located between species, within species, within individuals or within the leaves themselves; (ii) whether trait values collected using standardized methods correlate with those collected using unstandardized methods; and (iii) to what extent can we differentiate plant species on the basis of their traits? 4.,We find that the majority of variation in traits was often explained by between species differences; however, between leaflet trait variation was very high for compound-leaved species. We also show that many species are difficult to reliably differentiate on the basis of functional traits even when sampling many individuals. 5.,We suggest an ideal sample size of at least 10, and ideally 20, individuals be used when calculating mean trait values for individual species for entire communities, though even at large sample sizes, it remains unclear if community level trait values will allow comparisons on a larger geographic scale or if species traits are generally similar across scales. It will thus be critical to account for intraspecific variation by comparing species mean trait values across space in multiple microclimatic environments within local communities and along environmental gradients. Further, quantifying trait variability due to plasticity and inheritance will provide a better understanding of the underlying patterns and drivers of trait variation as well as the application of functional traits in outlining mechanisms of species co-existence. [source] An examination of the intentional and unintentional aspects of medication non-adherence in patients diagnosed with hypertensionJOURNAL OF CLINICAL NURSING, Issue 4 2007Elaine Lehane MSc Aims., The primary aim of this study was to describe the unintentional and intentional aspects of non-adherence in patients diagnosed with hypertension. A secondary aim was to examine the relationships between medication adherence and purposeful actions (intentional non-adherence), patterned behaviours (unintentional non-adherence) and demographic questionnaire variables. Background., Non-adherence to medications continues to be a significant health-care issue, the extent and consequences of which have been well documented. Despite considerable research over the past five decades, little progress has been made in solving this healthcare problem. Recent literature indicates that this lack of progress can be attributed to the fact that past research has concentrated solely upon either the unintentional or the intentional aspects of non-adherence, instead of addressing both facets simultaneously. Methods., A quantitative, descriptive, correlation research design was employed using Johnson's (2002) Medication Adherence Model as a theoretical framework. A convenience sample of 73 participants with hypertension, attending the outpatients' clinics of two university hospitals was recruited. Data were collected by means of a researcher administered questionnaire and analysed using the Statistical Package for Social Sciences. Results., High levels of medication adherence with a mean adherence score of 4·75 (maximum 5) were reported. Low and medium levels of purposeful actions and medium and high levels of patterned behaviours towards medication taking were found. Correlational analyses did not demonstrate statistically significant associations. Conclusions., Both the intentional and unintentional dimensions of medication-taking are simultaneously considered by patients to varying levels when adhering to therapeutic regimens. This is an important research area for nurses as it facilitates an increased understanding of non-adherence and, in so doing, aids the uncovering of more effective interventions aimed at sustaining lifelong pharmacotherapy. Relevance to clinical practice., By acknowledging a broader approach to patient medication-taking, nurses will be able more effectively to assess and intervene in non-adherent behaviours and actions. [source] Inter-Organizational Knowledge Transfer: Current Themes and Future ProspectsJOURNAL OF MANAGEMENT STUDIES, Issue 4 2008Mark Easterby-Smith abstract Many papers have been published recently in the fields of strategy and international business research incorporating the role of organizational knowledge as a basis of firm competitive advantage. While such knowledge is normally developed within the firm, it is important that firms possess the ability to learn from others in order to meet the increasing pace of competition. Knowledge transfer, defined here as an event through which one organization learns from the experience of another, has thus become an important research area within the broader domain of organizational learning and knowledge management. This paper presents a theoretical framework, identifies key themes covered by the six articles included in the Special Issue on Inter-Organizational Knowledge Transfer, and then discusses priorities for future research. [source] GENETIC STUDY: Heritability and a genome-wide linkage analysis of a Type II/B cluster construct for cannabis dependence in an American Indian communityADDICTION BIOLOGY, Issue 3 2009Cindy L. Ehlers ABSTRACT Subtyping of substance dependence disorders holds promise for a number of important research areas including phenotyping for genetic studies, characterizing clinical course, and matching treatment and prevention strategies. This study sought to investigate whether a dichotomous construct similar to Babor's Types A/B and Cloninger's Types I/II for alcohol dependence can be identified for cannabis dependence in a Native American sample. In addition, heritability of this construct and its behavior in a genetic linkage analyses were evaluated. Information on cannabis use and dependence symptoms and other psychiatric disorders was obtained using the Semi-Structured Assessment for the Genetics of Alcoholism from a community sample of 606 American Indians. Hierarchical average linkage and K means cluster analysis was used, and a three-cluster solution was found to generate the best separation of variables. Ninety-one per cent of cannabis-dependent participants fell into one of the two subtypes: Type A/I cluster (n = 114, 56%) and Type B/II cluster (n = 70, 35%). Heritability (estimated using Sequential Oligogenic Linkage Analysis Routines) was only significant for the Type B/II cluster (h2 = 0.44, SE = 0.18, P < 0.01). Evidence for linkage was found for the Type B/II cluster (versus no diagnosis) on chromosome 16 [at 139 centimorgans (cM), Log of the Odds (LOD) score = 4.4], and on chromosome 19 (at 74 cM, LOD score = 6.4). Regions of interest for this phenotype (LOD > 1.5) were also located on chromosomes 14, 21, 22. These findings suggest that a Type B/II cannabis dependence phenotype can be identified in this population and that it is in part heritable and linked to areas of the genome identified previously for drug dependence phenotypes in this population as well as in other studies. [source] The measurement and importance of red cell survivalAMERICAN JOURNAL OF HEMATOLOGY, Issue 2 2009Robert S. Franco The measurement of red blood cell survival in the circulation has progressed from the original differential agglutination technique of Ashby to current isotopic and flow cytometric methods. While occasionally useful in the clinic, these methods find widespread use in a number of important research areas, including the evaluation of new red cell storage media in transfusion medicine and studies of the pathophysiology of sickle cell disease and diabetes. In this review, measurement techniques are placed in historical perspective and examined for relative merits and suitable application. Am. J. Hematol., 2009. © 2008 Wiley-Liss, Inc. [source] | |||||||||||||