Showing papers by "Queen's University published in 2006"

Lost in knowledge translation: time for a map?

Abstract: There is confusion and misunderstanding about the concepts of knowledge translation, knowledge transfer, knowledge exchange, research utilization, implementation, diffusion, and dissemination. We review the terms and definitions used to describe the concept of moving knowledge into action. We also offer a conceptual framework for thinking about the process and integrate the roles of knowledge creation and knowledge application. The implications of knowledge translation for continuing education in the health professions include the need to base continuing education on the best available knowledge, the use of educational and other transfer strategies that are known to be effective, and the value of learning about plannedaction theories to be better able to understand and influence change in practice settings.

Modeling the Antecedents of Proactive Behavior at Work

Abstract: Using a sample of U.K. wire makers (N = 282), the authors tested a model in which personality and work environment antecedents affect proactive work behavior via cognitive-motivational mechanisms. Self-reported proactive work behaviors (proactive idea implementation and proactive problem solving) were validated against rater assessments for a subsample (n = 60) of wire makers. With the exception of supportive supervision, each antecedent was important, albeit through different processes. Proactive personality was significantly associated with proactive work behavior via role breadth self-efficacy and flexible role orientation, job autonomy was also linked to proactive behavior via these processes, as well as directly; and coworker trust was associated with proactive behavior via flexible role orientation. In further support of the model, the cognitive-motivational processes for proactive work behavior differed from those for the more passive outcome of generalized compliance.

Immigrant Youth: Acculturation, Identity, and Adaptation

Abstract: Cet article presente plusieurs des principaux resultats d’une grande etude internationale sur l’acculturation et l’adaptation de jeunes immigres (âges de 13 a 18 ans) qui se sont implantes dans treize pays (N = 5,366); il y est adjoint un echantillon de jeunes nationaux (N = 2,631). La recherche s’appuyait sur trois questions centrales: comment les jeunes migrants gerent-ils le processus d’acculturation? Comment parviennent-ils a s’adapter? Et y a-t-il un lien manifeste entre la forme d’acculturation et le succes de l’adaptation? L’analyse en clusters deboucha sur quatre profils d’acculturation: integrateur, ethnique, national et diffus. L’analyse factorielle de cinq variables d’adaptation mit en evidence deux types d’adaptation: psychologique et socioculturel. Il existe une forte relation entre la facon dont les jeunes s’acculturent et leur adaptation: ceux qui presentent un profil integrateur beneficient des meilleurs indicateurs d’adaptations psychologique et socioculturelle alors que ceux souffrant d’un profil diffus ont les pires. Entre les deux, le profil ethnique presente une adaptation psychologique relativement bonne et une adaptation socioculturelle plutot pauvre, tandis que le profil national a une adaptation psychologique relativement pauvre et une adaptation socioculturelle legerement negative. Cette configuration de resultats fut en grande partie retrouvee a travers une modelisation en equation structurelle. Les consequences pour l’implantation des jeunes immigres sont claires: ils devraient etre encourages a preserver l’appartenance a leur culture d’origine tout en etablissant des liens etroits avec la societe d’accueil. This paper reports some of the main findings from a large international study of the acculturation and adaptation of immigrant youth (aged 13 to 18 years) who are settled in 13 societies (N= 5,366), as well as a sample of national youth (N= 2,631). The study was guided by three core questions: How do immigrant youth deal with the process of acculturation? How well do they adapt? Are there important relationships between how they acculturate and how well they adapt? Cluster analysis produced four distinct acculturation profiles: integration, ethnic, national, and diffuse. Factor analysis of five adaptation variables revealed two distinct forms of adaptation: psychological and sociocultural. There were substantial relationships between how youth acculturate and how well they adapt: those with an integration profile had the best psychological and sociocultural adaptation outcomes, while those with a diffuse profile had the worst; in between, those with an ethnic profile had moderately good psychological adaptation but poorer sociocultural adaptation, while those with a national profile had moderately poor psychological adaptation, and slightly negative sociocultural adaptation. This pattern of results was largely replicated using structural equation modeling. Implications for the settlement of immigrant youth are clear: youth should be encouraged to retain both a sense of their own heritage cultural identity, while establishing close ties with the larger national society.

A simple effective potential for exchange.

Abstract: The optimized effective potential (OEP) for exchange was introduced some time ago by Sharp and Horton [Phys. Rev. 90, 317 (1953)] and by Talman and Shadwick [Phys. Rev. A 14, 36 (1976)]. The integral equation for the OEP is difficult to solve, however, and a variety of approximations have therefore been proposed. These are explicitly orbital dependent and require the same two-electron integrals as Hartree-Fock theory. We have found a remarkably simple approximate effective potential that closely resembles the Talman-Shadwick potential in atoms. It depends only on total densities and requires no two-electron integrals.

Evidence supporting paracrine hypothesis for Akt-modified mesenchymal stem cell-mediated cardiac protection and functional improvement

Abstract: We previously reported that intramyocardial injection of bone marrow-derived mesenchymal stem cells overexpressing Akt (Akt-MSCs) inhibits ventricular remodeling and restores cardiac function measured 2 wk after myocardial infarction. Here, we report that the functional improvement occurs in < 72 h. This early remarkable effect cannot be readily attributed to myocardial regeneration from the donor cells. Thus, we hypothesized that paracrine actions exerted by the cells through the release of soluble factors might be important mechanisms of tissue repair and functional improvement after injection of the Akt-MSCs. Indeed, in the current study we demonstrate that conditioned medium from hypoxic Akt-MSCs markedly inhibits hypoxia-induced apoptosis and triggers vigorous spontaneous contraction of adult rat cardiomyocytes in vitro. When injected into infarcted hearts, the Akt-MSC conditioned medium significantly limits infarct size and improves ventricular function relative to controls. Support to the paracrine...

Lectures on the Combinatorics of Free Probability

Abstract: Part I. Basic Concepts: 1. Non-commutative probability spaces and distributions 2. A case study of non-normal distribution 3. C*-probability spaces 4. Non-commutative joint distributions 5. Definition and basic properties of free independence 6. Free product of *-probability spaces 7. Free product of C*-probability spaces Part II. Cumulants: 8. Motivation: free central limit theorem 9. Basic combinatorics I: non-crossing partitions 10. Basic Combinatorics II: Mobius inversion 11. Free cumulants: definition and basic properties 12. Sums of free random variables 13. More about limit theorems and infinitely divisible distributions 14. Products of free random variables 15. R-diagonal elements Part III. Transforms and Models: 16. The R-transform 17. The operation of boxed convolution 18. More on the 1-dimensional boxed convolution 19. The free commutator 20. R-cyclic matrices 21. The full Fock space model for the R-transform 22. Gaussian Random Matrices 23. Unitary Random Matrices Notes and Comments Bibliography Index.

Social evolution theory for microorganisms

Abstract: Microorganisms communicate and cooperate to perform a wide range of multicellular behaviours, such as dispersal, nutrient acquisition, biofilm formation and quorum sensing. Microbiologists are rapidly gaining a greater understanding of the molecular mechanisms involved in these behaviours, and the underlying genetic regulation. Such behaviours are also interesting from the perspective of social evolution - why do microorganisms engage in these behaviours given that cooperative individuals can be exploited by selfish cheaters, who gain the benefit of cooperation without paying their share of the cost? There is great potential for interdisciplinary research in this fledgling field of sociomicrobiology, but a limiting factor is the lack of effective communication of social evolution theory to microbiologists. Here, we provide a conceptual overview of the different mechanisms through which cooperative behaviours can be stabilized, emphasizing the aspects most relevant to microorganisms, the novel problems that microorganisms pose and the new insights that can be gained from applying evolutionary theory to microorganisms.

Paleontological Evidence to Date the Tree of Life

Abstract: The role of fossils in dating the tree of life has been misunderstood. Fossils can provide good "minimum" age estimates for branches in the tree, but "maximum" constraints on those ages are poorer. Current debates about which are the "best" fossil dates for calibration move to consideration of the most appropriate constraints on the ages of tree nodes. Because fossil-based dates are constraints, and because molecular evolution is not perfectly clock-like, analysts should use more rather than fewer dates, but there has to be a balance between many genes and few dates versus many dates and few genes. We provide "hard" minimum and "soft" maximum age constraints for 30 divergences among key genome model organisms; these should contribute to better understanding of the dating of the animal tree of life.

Identity, Intended Image, Construed Image, and Reputation: An Interdisciplinary Framework and Suggested Terminology

Abstract: Many scholars across various academic disciplines are investigating the following questions: What do individuals know or believe about an organization? How does a focal organization (and/or other interested entity) develop, use, and/or change this information? and How do individuals respond to what they know or believe about an organization? Cross-disciplinary research that centers on these questions is desirable and could be enhanced if researchers identify and develop consistent terminology for framing these questions. The authors work toward that end by identifying four central ‘viewpoints’ of an organization and proposing labels to represent each of these viewpoints:identity, intended image, construed image, andreputation.

A post-Hartree-Fock model of intermolecular interactions: inclusion of higher-order corrections.

Abstract: We have previously demonstrated that the dipole moment of the exchange hole can be used to derive intermolecular C6 dispersion coefficients [J. Chem. Phys. 122, 154104 (2005)]. This was subsequently the basis for a novel post-Hartree-Fock model of intermolecular interactions [J. Chem. Phys. 123, 024101 (2005)]. In the present work, the model is extended to include higher-order dispersion coefficients C8 and C10. The extended model performs very well for prediction of intermonomer separations and binding energies of 45 van der Waals complexes. In particular, it performs twice as well as basis-set extrapolated MP2 theory for dispersion-bound complexes, with minimal computational cost.

Human Brands: Investigating Antecedents to Consumers' Strong Attachments to Celebrities

Abstract: This article explores recent advances in self-determination research to address why consumers develop strong attachments to “human brands,” a term that refers to any well-known persona who is the subject of marketing communications efforts. Study 1 uses a survey that is analyzed with structural equation modeling. Study 2 is qualitative and offers corroborating evidence for the proposed theoretical model. Study 3 extends the model with a more naturalistic sample and tests several alternative hypotheses using hierarchical regression. The results suggest that when a human brand enhances a person's feelings of autonomy and relatedness and does not suppress feelings of competence, the person is likely to become more strongly attached to it. This article documents that strong attachments are predictive of satisfied, trusting, and committed relationships and proposes that attachment strength may be a parsimonious proxy for consumer–brand relationship strength. The results imply that benefits would accru...

The family affluence scale as a measure of national wealth: validation of an adolescent self-report measure

Abstract: One explanation for a lack of consistency in SES-health associations in youth is that parent-based income and occupation measures are inadequate. The Family Affluence Scale (FAS), a four-item measure of family wealth, has been developed in the WHO Health Behaviour in School-aged Children Study as an alternative measure. The aim of this paper is to examine the criterion and construct validity of the FAS as a measure of national absolute wealth in 35 countries. A general measure of national wealth, Gross Domestic Product (GDP) for the year 2001, corrected for Purchasing Power Parity, was used as a gold standard. For the composite FAS index, there was a similar strength in country rank order correlation (0.87) as with GDP, and a Kappa agreement coefficient of 0.57, indicating good criterion validity. FAS index associations with national health indicators were systematically higher than the values obtained with GDP. These features suggest that FAS can be used with confidence in aggregate analyses of HBSC data that focus on relationships between SES and adolescent health.

On the nature and importance of cultural tightness-looseness.

Abstract: Cross-cultural research is dominated by the use of values despite their mixed empirical support and their limited theoretical scope. This article expands the dominant paradigm in cross-cultural research by developing a theory of cultural tightness-looseness (the strength of social norms and the degree of sanctioning within societies) and by advancing a multilevel research agenda for future research. Through an exploration of the top-down, bottom-up, and moderating impact that cultural tightness-looseness has on individuals and organizations, as well as on variance at multiple levels of analysis, the theory provides a new and complementary perspective to the values approach.

Age, gender, and the underutilization of mental health services: The influence of help-seeking attitudes

Abstract: The objectives of this study were to explore age and gender differences in attitudes toward seeking professional psychological help, and to examine whether attitudes negatively influence intentions to seek help among older adults and men, whose mental health needs are underserved. To achieve these objectives 206 community-dwelling adults completed questionnaires measuring help-seeking attitudes, psychiatric symptomatology, prior help-seeking, and intentions to seek help. Older age and female gender were associated with more positive help-seeking attitudes in this sample, although age and gender interacted with marital status and education, and had varying influences on different attitude components. Age and gender also influenced intentions to seek professional psychological help. Women exhibited more favourable intentions to seek help from mental health professionals than men, likely due to their positive attitudes concerning psychological openness. Older adults exhibited more favourable intentions to seek help from primary care physicians than younger adults, a finding that was not explained by age differences in attitudes. Results from this study suggest that negative attitudes related to psychological openness might contribute to men's underutilization of mental health services. Help-seeking attitudes do not appear to be a barrier to seeking professional help among older adults, although their intentions to visit primary care physicians might be. These findings suggest the need for education to improve men's help-seeking attitudes and to enhance older adults' willingness to seek specialty mental health services.

Transmembrane transport of endo- and xenobiotics by mammalian ATP-binding cassette multidrug resistance proteins

Abstract: Multidrug Resistance Proteins (MRPs), together with the cystic fibrosis conductance regulator (CFTR/ABCC7) and the sulfonylurea receptors (SUR1/ABCC8 and SUR2/ABCC9) comprise the 13 members of the ...

The Development of Executive Functioning and Theory of Mind A Comparison of Chinese and U.S. Preschoolers

Abstract: Preschoolers' theory-of-mind development follows a similar age trajectory across many cultures. To determine whether these similarities are related to similar underlying ontogenetic processes, we examined whether the relation between theory of mind and executive function commonly found among U.S. preschoolers is also present among Chinese preschoolers. Preschoolers from Beijing, China (N= 109), were administered theory-of-mind and executive-functioning tasks, and their performance was compared with that of a previously studied sample of U.S. preschoolers (N= 107). The Chinese preschoolers outperformed their U.S. counterparts on all measures of executive functioning, but were not similarly advanced in theory-of-mind reasoning. Nonetheless, individual differences in executive functioning predicted theory of mind for children in both cultures. Thus, the relation between executive functioning and theory of mind is robust across two disparate cultures. These findings shed light on why executive functioning is important for theory-of-mind development.

Sensitivity of secondary structure propensities to sequence differences between α‐ and γ‐synuclein: Implications for fibrillation

Abstract: The synucleins are a family of intrinsically disordered proteins involved in various human diseases. α-Synuclein has been extensively characterized due to its role in Parkinson's disease where it forms intracellular aggregates, while γ-synuclein is overexpressed in a majority of late-stage breast cancers. Despite fairly strong sequence similarity between the amyloid-forming regions of α- and γ-synuclein, γ-synuclein has only a weak propensity to form amyloid fibrils. We hypothesize that the different fibrillation tendencies of α- and γ-synuclein may be related to differences in structural propensities. Here we have measured chemical shifts for γ-synuclein and compared them to previously published shifts for α-synuclein. In order to facilitate direct comparison, we have implemented a simple new technique for re-referencing chemical shifts that we have found to be highly effective for both disordered and folded proteins. In addition, we have developed a new method that combines different chemical shifts into a single residue-specific secondary structure propensity (SSP) score. We observe significant differences between α- and γ-synuclein secondary structure propensities. Most interestingly, γ-synuclein has an increased α-helical propensity in the amyloid-forming region that is critical for α-synuclein fibrillation, suggesting that increased structural stability in this region may protect against γ-synuclein aggregation. This comparison of residue-specific secondary structure propensities between intrinsically disordered homologs highlights the sensitivity of transient structure to sequence changes, which we suggest may have been exploited as an evolutionary mechanism for fast modulation of protein structure and, hence, function.

Putative contributors to the secular increase in obesity: exploring the roads less traveled

Abstract: Putative contributors to the secular increase in obesity: exploring the roads less traveled

Visceral fat is an independent predictor of all-cause mortality in men.

Abstract: Objective: To examine the independent associations of abdominal fat (visceral and subcutaneous) and liver fat with all-cause mortality. Research Methods and Procedures: Participants included 291 men [97 decedents and 194 controls; mean age, 56.4 ± 12.0 (SD) years] who received a computed tomography (CT) examination at the preventive medicine clinic in Dallas, TX, between 1995 and 1999, with a mean mortality follow-up of 2.2 ± 1.3 years. Abdominal fat was determined using contiguous CT images from the L3-L4 to L4-L5 intervertebral space. Liver fat was assessed using the CT-determined liver attenuation value, which is inversely related to liver fat. Logistic regression was used to determine the independent association between the fat depots and all-cause mortality. Results: During the study, there were 97 deaths. Visceral fat [odds ratio (OR) per SD: 1.83; 95% CI: 1.23 to 2.73], abdominal subcutaneous fat (1.44; 1.02 to 2.03), liver fat (0.64; 0.46 to 0.87), and waist circumference (1.41; 1.01 to 1.98) were significant individual predictors of mortality after controlling for age and length of follow-up. In a model including all three fat measures (subcutaneous, visceral, and liver fat), age, and length of follow-up, only visceral fat (1.93; 1.15 to 3.23) was a significant predictor of mortality. Discussion: Visceral fat is a strong, independent predictor of all-cause mortality in men.

Dealing with missing data in a multi-question depression scale: a comparison of imputation methods

Abstract: Missing data present a challenge to many research projects. The problem is often pronounced in studies utilizing self-report scales, and literature addressing different strategies for dealing with missing data in such circumstances is scarce. The objective of this study was to compare six different imputation techniques for dealing with missing data in the Zung Self-reported Depression scale (SDS). 1580 participants from a surgical outcomes study completed the SDS. The SDS is a 20 question scale that respondents complete by circling a value of 1 to 4 for each question. The sum of the responses is calculated and respondents are classified as exhibiting depressive symptoms when their total score is over 40. Missing values were simulated by randomly selecting questions whose values were then deleted (a missing completely at random simulation). Additionally, a missing at random and missing not at random simulation were completed. Six imputation methods were then considered; 1) multiple imputation, 2) single regression, 3) individual mean, 4) overall mean, 5) participant's preceding response, and 6) random selection of a value from 1 to 4. For each method, the imputed mean SDS score and standard deviation were compared to the population statistics. The Spearman correlation coefficient, percent misclassified and the Kappa statistic were also calculated. When 10% of values are missing, all the imputation methods except random selection produce Kappa statistics greater than 0.80 indicating 'near perfect' agreement. MI produces the most valid imputed values with a high Kappa statistic (0.89), although both single regression and individual mean imputation also produced favorable results. As the percent of missing information increased to 30%, or when unbalanced missing data were introduced, MI maintained a high Kappa statistic. The individual mean and single regression method produced Kappas in the 'substantial agreement' range (0.76 and 0.74 respectively). Multiple imputation is the most accurate method for dealing with missing data in most of the missind data scenarios we assessed for the SDS. Imputing the individual's mean is also an appropriate and simple method for dealing with missing data that may be more interpretable to the majority of medical readers. Researchers should consider conducting methodological assessments such as this one when confronted with missing data. The optimal method should balance validity, ease of interpretability for readers, and analysis expertise of the research team.

National survey of doses from CT in the UK: 2003.

Abstract: A review of patient doses from CT examinations in the UK for 2003 has been conducted on the basis of data received from over a quarter of all UK scanners, of which 37% had multislice capability. Questionnaires were employed to collect scan details both for the standard protocols established at each scanner for 12 common types of CT examination on adults and children, and for samples of individual patients. This information was combined with published scanner-specific CT dose index (CTDI) coefficients to estimate values of the standard dose indices CTDIw and CTDIvol for each scan sequence. Knowledge of each scan length allowed assessment of the dose–length product (DLP) for each examination, from which effective doses were then estimated. When compared with a previous UK survey for 1991, wide variations were still apparent between CT centres in the doses for standard protocols. The mean UK doses for adult patients were in general lower by up to 50% than those for 1991, although doses were slightly higher f...

Acetaminophen for osteoarthritis

Abstract: Background Osteoarthritis (OA) is the most common form of arthritis. Published guidelines and expert opinion are divided over the relative role of acetaminophen (also called paracetamol or Tylenol) and non-steroidal anti-inflammatory drugs (NSAIDs) as first-line pharmacologic therapy. The comparative safety of acetaminophen and NSAIDs is also important to consider. This update to the original 2003 review includes nine additional RCTs. Objectives To assess the efficacy and safety of acetaminophen versus placebo and versus NSAIDs (ibuprofen, diclofenac, arthrotec, celecoxib, naproxen, rofecoxib) for treating OA. Search methods We searched MEDLINE (up to July 2005), EMBASE (2002-July 2005), Cochrane Central Register of Controlled Trials (CENTRAL), ACP Journal Club, DARE, Cochrane Database of Systematic Reviews (all from 1994 to July 2005). Reference lists of identified RCTs and pertinent review articles were also hand searched. Selection criteria Published randomized controlled trials (RCTs) evaluating the efficacy and safety of acetaminophen alone in OA were considered for inclusion. Data collection and analysis Pain, physical function and global assessment outcomes were reported. Results for continuous outcome measures were expressed as standardized mean differences (SMD). Dichotomous outcome measures were pooled using relative risk (RR) and the number needed to treat (NNT) was calculated. Main results Fifteen RCTs involving 5986 participants were included in this review. Seven RCTs compared acetaminophen to placebo and ten RCTs compared acetaminophen to NSAIDs. In the placebo-controlled RCTs, acetaminophen was superior to placebo in five of the seven RCTs and had a similar safety profile. Compared to placebo, a pooled analysis of five trials of overall pain using multiple methods demonstrated a statistically significant reduction in pain (SMD -0.13, 95% CI -0.22 to -0.04), which is of questionable clinical significance. The relative percent improvement from baseline was 5% with an absolute change of 4 points on a 0 to 100 scale. The NNT to achieve an improvement in pain ranged from 4 to 16. In the comparator-controlled RCTs, acetaminophen was less effective overall than NSAIDs in terms of pain reduction, global assessments and in terms of improvements in functional status. No significant difference was found overall between the safety of acetaminophen and NSAIDs, although patients taking traditional NSAIDS were more likely to experience an adverse GI event (RR 1.47, (95% CI 1.08 to 2.00). 19% of patients in the traditional NSAID group versus 13% in the acetaminophen group experienced an adverse GI event. However, the median trial duration was only 6 weeks and it is difficult to assess adverse outcomes in a relatively short time period. Authors' conclusions The evidence to date suggests that NSAIDs are superior to acetaminophen for improving knee and hip pain in people with OA. The size of the treatment effect was modest, and the median trial duration was only six weeks, therefore, additional considerations need to be factored in when making the decision between using acetaminophen or NSAIDs. In OA subjects with moderate-to-severe levels of pain, NSAIDs appear to be more effective than acetaminophen.

Antecedents and outcomes of strategic IS alignment: an empirical investigation

Abstract: Prior research argues that alignment between business and information systems (IS) strategies enhances organizational performance. However, factors affecting alignment have received relatively little empirical attention. Moreover, IS strategic alignment is assumed to facilitate the performance of all organizations, regardless of type or business strategy. By using two studies of business firms and academic institutions, this paper: 1) develops and tests a model relating alignment, its antecedents, and its consequences and 2) examines differences in these relationships across organizational types and strategies. Findings indicate that alignment depends on shared domain knowledge and prior IS success, and also support the expected positive impact of alignment on organizational performance. Differences across Prospector, Analyzer, and Defender business strategies are examined. A key research contribution is the empirical demonstration that the importance of alignment, as well as the mechanisms used to attain alignment, vary by business strategy and industry. In past alignment studies, controlling for industry has not been uncommon. The findings suggest that future research studies should also control for business strategy. The article also empirically demonstrates that past implementation success influences alignment. In addition, it highlights the influence of a process variable, strategic planning, on the development of shared knowledge and, consequently, on alignment. This paper examines strategic issues related to the management of technology. Data from multiple surveys are used to test the extent to which strategic planning, shared business-IS knowledge, prior IS success, and other variables consistently enhance IS alignment. The study also provides empirical support for the popular argument that IS alignment improves organizational performance. It extends the current literature by examining the extent to which these findings hold across firm strategies and industries. The authors argue that not all firms are equally well served by allocating scarce resources to improve IS alignment.