546 research outputs found
Dealing with social desirability bias: An application to charitable giving
Purpose: This paper aims to address the issue of survey distortion caused by one of the most common and pervasive sources of bias, namely social desirability bias (SDB). Despite 50 years of research, there are still many unanswered questions about its conceptualisation and operationalisation. The authors argue that traditional measures of SDB are inadequate and that the context in which the research is being conducted should be reflected in the measures employed. Hence, the authors develop and validate a multi-dimensional scale that may be used to measure the degree of SDB present in responses to giving surveys. Design/methodology/approach: Following initial scale development procedures a convenience sample of 820 donors to a national charity was employed to refine the resultant scale items. Exploratory factor analysis and reliability tests were conducted to establish the dimensionality of the new scale and its reliability. Using a separate sample of 1,500 active donors, the scale was then subject to confirmatory procedures to test its predictive validity. Findings: The findings support the assertion that SDB is a multi-dimensional construct consisting of six dimensions. However, in the context of postal surveys it is found that self-deception and the degree of intrinsic benefit accruing to a donor are the primary determinants of the level of SDB an individual will exhibit. The authors also highlight the significance of the SDB issue since in the survey reported here, 65 per cent of respondents were found to over-report their giving. Originality/value: This is one of the first published studies that has been able to explore the predictive validity of a SDB scale. The work has expanded our understanding of the determinants of SDB and provided an instrument that may now be employed to reduce a significant proportion of this error in giving surveys. © Emerald Group Publishing Limited
The Possibility of Inflation in Asymptotically Safe Gravity
We examine the inflationary modes in the cubic curvature theories in the
context of asymptotically safe gravity. On the phase space of the Hubble
parameter, there exists a critical point which corresponds to the slow-roll
inflation in Einstein frame. Most of the e-foldings are attained around the
critical point for each inflationary trajectories. If the coupling constants
have the parametric relations generated as the power of the relative
energy scale of inflation to the ultraviolet cutoff , a
successful inflation with more than 60 e-foldings occurs near the critical
point.Comment: 14 pages, 4 figure
Giraffe translocation population viability analysis
Most populations of giraffes have declined in recent decades, leading to the recent IUCN decision to upgrade the species to Vulnerable status, and some subspecies to Endangered. Translocations have been used as a conservation tool to re-introduce giraffes to previously occupied areas or establish new populations, but guidelines for founding populations are lacking. To provide general guidelines for translocation projects regarding feasibility, we simulated various scenarios of translocated giraffe populations to identify viable age and sex distributions of founding populations using population viability analysis (PVA) implemented in Vortex software. We explored the parameter space for demography and the genetic load, examining how variation in founding numbers and sex ratios affected 100 yr probability of population extinction and genetic diversity. We found that even very small numbers of founders (N †10 females) can appear to be successful in the first decades due to transient positive population growth, but with moderate population growth rate and moderate genetic load, long-term population viability (probability of extinction 95% genetic diversity of the source population in an isolated population, 50 females and 5 males are recommended to compose the founding population. Sensitivity analyses revealed first-year survival and reproductive rate were the simulation parameters with the greatest proportional influence on probability of extinction and genetic diversity. These simulations highlight important considerations for translocation success and data gaps including true genetic load in wild giraffe populations
Genetic identification of a novel NeuroD1 function in the early differentiation of islet α, PP and Δ cells
AbstractNkx2.2 and NeuroD1 are vital for proper differentiation of pancreatic islet cell types. Nkx2.2-null mice fail to form ÎČ cells, have reduced numbers of α and PP cells and display an increase in ghrelin-producing Δ cells. NeuroD1-null mice display a reduction of α and ÎČ cells after embryonic day (e) 17.5. To begin to determine the relative contributions of Nkx2.2 and NeuroD1 in islet development, we generated Nkx2.2â/â;NeuroD1â/â double knockout (DKO) mice. As expected, the DKO mice fail to form ÎČ cells, similar to the Nkx2.2-null mice, suggesting that the Nkx2.2 phenotype may be dominant over the NeuroD1 phenotype in the ÎČ cells. Surprisingly, however, the α, PP and Δ phenotypes of the Nkx2.2-null mice are partially rescued by the simultaneous elimination of NeuroD1, even at early developmental time points when NeuroD1 null mice alone do not display a phenotype. Our results indicate that Nkx2.2 and NeuroD1 interact to regulate pancreatic islet cell fates, and this epistatic relationship is cell-type dependent. Furthermore, this study reveals a previously unappreciated early function of NeuroD1 in regulating the specification of α, PP and Δ cells
Process evaluation of a sport-for-health intervention to prevent smoking amongst primary school children: SmokeFree Sports
Background: SmokeFree Sports (SFS) was a multi-component sport-for-health intervention aiming at preventing smoking among nine to ten year old primary school children from North West England. The purpose of this study was to evaluate the process and implementation of SFS, examining intervention reach, dose, fidelity, acceptability and sustainability, in order to understand the feasibility and challenges of delivering such interventions and inform interpretations of intervention effectiveness. Methods: Process measures included: booking logs, 18 focus groups with children (n=95), semi-structured interviews with teachers (n=20) and SFS coaches (n=7), intervention evaluation questionnaires (completed by children, n=1097; teachers, n=50), as well direct observations (by researchers, n=50 observations) and self-evaluations (completed by teachers, n=125) of intervention delivery (e.g. length of sessions, implementation of activities as intended, children's engagement and barriers). Descriptive statistics and thematic analysis were applied to quantitative and qualitative data, respectively. Results: Overall, SFS reached 30.8% of eligible schools, with 1073 children participating in the intervention (across 32 schools). Thirty-one schools completed the intervention in full. Thirty-three teachers (55% female) and 11 SFS coaches (82% male) attended a bespoke SFS training workshop. Disparities in intervention duration (range=126 to 201 days), uptake (only 25% of classes received optional intervention components in full), and the extent to which core (mean fidelity score of coaching sessions=58%) and optional components (no adaptions made=51% of sessions) were delivered as intended, were apparent. Barriers to intervention delivery included the school setting and children's behaviour and knowledge. SFS was viewed positively (85% and 82% of children and teachers, respectively, rated SFS five out of five) and recommendations to increase school engagement were provided. Conclusion: SFS was considered acceptable to children, teachers and coaches. Nevertheless, efforts to enhance intervention reach (at the school level), teachers' engagement and sustainability must be considered. Variations in dose and fidelity likely reflect challenges associated with complex intervention delivery within school settings and thus a flexible design may be necessary. This study adds to the limited scientific evidence base surrounding sport-for-health interventions and their implementation, and suggests that such interventions offer a promising tool for engaging children in activities which promote their health
Impact of Surface Ligand on the Biocompatibility of InP/ZnS Quantum Dots with Platelets
InP/ZnS quantum dots (QDs) have received a large focus in recent years as a safer alternative to heavy metal-based QDs. Given their intrinsic fluorescent imaging capabilities, these QDs can be potentially relevant for in vivo platelet imaging. The InP/ZnS QDs are synthesized and their biocompatibility investigated through the use of different phase transfer agents. Analysis of platelet function indicates that platelet-QD interaction can occur at all concentrations and for all QD permutations tested. However, as the QD concentration increases, platelet aggregation is induced by QDs alone independent of natural platelet agonists. This study helps to define a range of concentrations and coatings (thioglycolic acid and penicillamine) that are biocompatible with platelet function. With this information, the platelet-QD interaction can be identified using multiple methods. Fluorescent lifetime imaging microscopy (FLIM) and confocal studies have shown QDs localize on the surface of the platelet toward the center while showing evidence of energy transfer within the QD population. It is believed that these findings are an important stepping point for the development of fluorescent probes for platelet imaging
A multicenter study of acute testicular torsion in the time of COVID-19
Background: Testicular torsion is a surgical emergency, and time to detorsion is imperative for testicular salvage. During the COVID-19 pandemic, patients may delay emergency care due to stay-at-home orders and concern of COVID-19 exposure. Objective: To assess whether emergency presentation for testicular torsion was delayed during the COVID-19 pandemic, and whether the rate of orchiectomy increased compared to a retrospective period. Study design: Patients were prospectively enrolled in a multicenter study from seven institutions in the United States and Canada. Inclusion criteria were patients two months to 18 years of age with acute testicular torsion from March through July 2020. The retrospective group included patients from January 2019 through February 2020. Statistical analysis was performed using KruskalâWallis tests, Chi-square tests, and logistic regression. Results: A total of 221 patients were included: 84 patients in the COVID-19 cohort and 137 in the retrospective cohort. Median times from symptom onset to emergency department presentation during COVID-19 compared to the retrospective period were 17.9 h (IQR 5.5â48.0) and 7.5 h (IQR 4.0â28.0) respectively (p = 0.04). In the COVID-19 cohort, 42% of patients underwent orchiectomy compared to 29% of pre-pandemic controls (p = 0.06). During COVID-19, 46% of patients endorsed delay in presentation compared to 33% in the retrospective group (p = 0.04). Discussion: We found a significantly longer time from testicular torsion symptom onset to presentation during the pandemic and a higher proportion of patients reported delaying care. Strengths of the study include the number of included patients and the multicenter prospective design during the pandemic. Limitations include a retrospective pre-pandemic comparison group. Conclusions: In a large multicenter study we found a significantly longer time from testicular torsion symptom onset to presentation during the pandemic and a significantly higher proportion of patients reported delaying care. Based on the findings of this study, more patient education is needed on the management of testicular torsion during a pandemic
Reading the biomineralized book of life: expanding otolith biogeochemical research and applications for fisheries and ecosystem-based management
Chemical analysis of calcified structures continues to flourish, as analytical and technological advances enable researchers to tap into trace elements and isotopes taken up in otoliths and other archival tissues at ever greater resolution. Increasingly, these tracers are applied to refine age estimation and interpretation, and to chronicle responses to environmental stressors, linking these to ecological, physiological, and life-history processes. Here, we review emerging approaches and innovative research directions in otolith chemistry, as well as in the chemistry of other archival tissues, outlining their value for fisheries and ecosystem-based management, turning the spotlight on areas where such biomarkers can support decision making. We summarise recent milestones and the challenges that lie ahead to using otoliths and archival tissues as biomarkers, grouped into seven, rapidly expanding and application-oriented research areas that apply chemical analysis in a variety of contexts, namely: (1) supporting fish age estimation; (2) evaluating environmental stress, ecophysiology and individual performance; (3) confirming seafood provenance; (4) resolving connectivity and movement pathways; (5) characterising food webs and trophic interactions; (6) reconstructing reproductive life histories; and (7) tracing stock enhancement efforts. Emerging research directions that apply hard part chemistry to combat seafood fraud, quantify past food webs, as well as to reconcile growth, movement, thermal, metabolic, stress and reproductive life-histories provide opportunities to examine how harvesting and global change impact fish health and fisheries productivity. Ultimately, improved appreciation of the many practical benefits of archival tissue chemistry to fisheries and ecosystem-based management will support their increased implementation into routine monitoring.[GRAPHICS]
A multicenter study of acute testicular torsion in the time of COVID-19
Background: Testicular torsion is a surgical emergency, and time to detorsion is imperative for testicular salvage. During the COVID-19 pandemic, patients may delay emergency care due to stay-at-home orders and concern of COVID-19 exposure. Objective: To assess whether emergency presentation for testicular torsion was delayed during the COVID-19 pandemic, and whether the rate of orchiectomy increased compared to a retrospective period. Study design: Patients were prospectively enrolled in a multicenter study from seven institutions in the United States and Canada. Inclusion criteria were patients two months to 18 years of age with acute testicular torsion from March through July 2020. The retrospective group included patients from January 2019 through February 2020. Statistical analysis was performed using KruskalâWallis tests, Chi-square tests, and logistic regression. Results: A total of 221 patients were included: 84 patients in the COVID-19 cohort and 137 in the retrospective cohort. Median times from symptom onset to emergency department presentation during COVID-19 compared to the retrospective period were 17.9 h (IQR 5.5â48.0) and 7.5 h (IQR 4.0â28.0) respectively (p = 0.04). In the COVID-19 cohort, 42% of patients underwent orchiectomy compared to 29% of pre-pandemic controls (p = 0.06). During COVID-19, 46% of patients endorsed delay in presentation compared to 33% in the retrospective group (p = 0.04). Discussion: We found a significantly longer time from testicular torsion symptom onset to presentation during the pandemic and a higher proportion of patients reported delaying care. Strengths of the study include the number of included patients and the multicenter prospective design during the pandemic. Limitations include a retrospective pre-pandemic comparison group. Conclusions: In a large multicenter study we found a significantly longer time from testicular torsion symptom onset to presentation during the pandemic and a significantly higher proportion of patients reported delaying care. Based on the findings of this study, more patient education is needed on the management of testicular torsion during a pandemic
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