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The effect of an oblique flow entry on the pressure losses in square channels
Get PDFFlows in square channels are common in applications, such as automotive after-treatment systems and heat exchangers. Flows with axial flow entry are well understood, but for oblique flow entry, there is no clarity on the additional pressure loss magnitude or the flow regime. Laminar flow is often assumed, even though flow separation at the channel entrance can cause a transition to turbulence. Here, the impact of oblique flow entry on the flow is investigated using LES (large eddy simulation) and RANS (Reynolds averaged Navier–Stokes) models, and their advantages and limitations are identified. The LES simulations show that the shear layer at the channel entrance produces continuous shedding of eddies that persist downstream even at moderate channel Reynolds numbers (≈ 2000). The LES predicted pressure losses mostly agree with experimental data, and the differences observed are attributed to the difficulty of accurately replicating the experimental geometry. It is shown that both LES and RANS results are sensitive to the rounding of the leading edge (present in experiments). Including edge rounding improves the pressure predictions. RANS simulations mostly agree with experimens, but unlike LES did not predict transitional flow phenomena for sharp leading edge. This study provides insight into the flow structure and sources of pressure losses in square channels, highlights the importance of understanding key flow and geometric features when using LES to predict complex flows involving flow separation and shear layers, and indicates the need to further investigate the complex instability arising from interactions between secondary flow and shear-layer roll-up.</p
Non-accidental violence toward sport officials:A scoping review
No full textThere is yet to be a focused review and synthesis on non-accidental violence toward sport officials despite a surge in academic inquiry into the topic over the last 25 years. As such, the aim of this review is to synthesize what is known about non-accidental violence toward sport officials. Articles were selected in March 2025. 32 articles were included in this scoping review with 13 countries and 7 sports represented. 43.7% of studies used qualitative methods, and only 4.1% of the total sample were women officials. Sport officials frequently experienced non-accidental violence, in particular verbal abuse from athletes, coaches, and spectators; organizations were identified as key contributors to the continuation of the problem. Non-accidental violence had serious consequences for sport officials including depression and attrition, particularly for those with limited organizational and/or social support. We recommend future researchers prioritize vulnerable and marginalized sport officiating groups and diversify methodological choices through employing in-depth qualitative methods, using robust demographic questionnaires, and expanding research questions
How can universities support students’ interfaith learning?:Findings from a longitudinal survey of students in the UK
No full textAcross the globe, on-campus religious diversity generates opportunities for learning and growth. But how can universities prepare students to learn about and engage positively with people with different religions and beliefs from their own? Put another way, how can universities best support students’ interfaith learning? This article explores how the university environment, or ‘campus climate’, influences one measure of interfaith learning, students’ positive engagement with religion and worldview difference (what we call ‘pluralism’). The data are drawn from a longitudinal survey of 1,000 university students in the United Kingdom (UK), surveyed twice during their studies, in 2021 and 2022. Statistical analysis reveals that increases in pluralism are shaped by the perception of a religiously diverse campus, safe spaces for spiritual expression, and provocative encounters which challenge students’ assumptions about their own, and others’, worldviews. Meanwhile, the analysis found that students who experience religion or worldview-related insensitivity or coercion at university are more likely to decline in their pluralism. Implications for higher education institutions are discussed
Integrative leadership in complex adaptive systems:a multi-modal analysis of strategic decision-making processes
No full textThis study examines the relationship between integrative leadership and strategic outcomes in complex adaptive systems. We aim to develop a theoretical framework that explains how leadership practices influence organizational adaptability in turbulent environments and provide practical guidance for organizational leaders.We employed a multi-modal methodology combining systematic meta-analysis of 87 empirical studies (2010-2025) with multi-level network analysis of six multinational organizations. This approach enabled triangulation across different data sources and analytical techniques to comprehensively map leadership-strategy dynamics across diverse organizational contexts.We identified six mechanisms through which leadership and strategy co-evolve: collective sensemaking, adaptive tension management, network reconfiguration, paradoxical integration, distributed cognition, and temporal synchronization. Network analysis revealed three distinct leadership-strategy configurations, with distributed-integrated networks demonstrating superior adaptive capacity. Organizations with moderate centralization, high cross-level connectivity, and dense middle management clusters exhibited 37% higher adaptive performance.Our sample focused on large multinational organizations, potentially limiting generalizability to smaller entities or different cultural contexts. Future research should examine leadership-strategy dynamics in diverse organizational types, entrepreneurial ventures, and ecosystem contexts.For practitioners, we provide actionable guidance for developing leadership systems that enhance strategic adaptability, including recommendations for leadership development, organizational design, and strategic decision-making processes that enable simultaneous exploration and exploitation in complex environments.In enhancing organizational adaptability, our framework contributes to organizational sustainability and resilience, potentially enabling more effective responses to societal challenges and promoting stable employment during periods of disruption and change.This study transcends traditional dichotomies between leadership and strategy by empirically mapping their co-evolution within complex adaptive systems, offering the novel concept of "network fluidity" as a critical capability for strategic adaptation in volatile environments.<br/
Between Session Reliability Of Traditional And Temporal Bilateral And Unilateral Dynamic Strength Index Calculations And Association With Sprint And Change Of Direction Performance
No full textTallis, J, Bolt, L, Morris, OR, Suchomel, TJ, and Eustace, SJ. Between session reliability of traditional and temporal bilateral and unilateral dynamic strength index calculations and association with sprint and change of direction performance. J Strength Cond Res XX(X): 000–000, 2025—The present study aimed to (a) evaluate the between session reliability of traditional and temporal based bilateral and unilateral dynamic strength index (DSI); (b) determine the association between DSI and sprint and change of direction performance in participants clustered by DSI root metrics. Thirty-eight recreationally active male participants (age: 23.4 ± 3.4 years) completed 20-m sprints, 5-0-5 change of direction test, bilateral and unilateral countermovement jumps (CMJ), and isometric midthigh pulls (IMTP) on 2 occasions. Vertical ground reaction force profiles were assessed to determine traditional DSI (DSIT), DSI based on mean force achieved after 100 milliseconds (DSI100), 150 milliseconds (DSI150), the entire CMJ propulsive phase (DSIP), and CMJ propulsive impulse (DSII). Bayesian interclass correlation coefficients and multiple linear regression after K-means clustering were used to analyze the data. Between session reliability of DSI was poor-moderate (interclass correlation coefficient [ICC] = 0.24–0.76) and highest for DSIT measures, albeit with some uncertainty (95% Higher Density Intervals [HDI]: 0.53–0.87). Bilateral temporal based DSI reliability was greater compared with unliteral equivalents, and temporal based DSI calculated for the nondominant limb, and those determined over a small-time epoch for the dominant limb were poor. There was limited association across DSI measures and straight-line 20-m sprint and 5-0-5 change of direction performance test. DSI100 for the dominant side had the strongest association with the performance outcomes (R2 = 0.33–0.36) and was improved in participants that expressed higher CMJ peak propulsive force. Dynamic strength index should be used with caution with respect to exercise prescription for the intention of improving tasks requiring rapid horizontal center of mass translation
First-nation Australian children’s interpretation of a pictorial questionnaire designed to assess physical literacy
Get PDFBackground: The Physical Literacy in Children Questionnaire (PL-C Quest) is a pictorial tool designed to measure children’s self-reported physical literacy. It measures 30 elements within the four domains (physical, psychological, cognitive, and social) of the Australian Physical Literacy Framework (APLF). The development study of the PL-C Quest only included children from non-Indigenous backgrounds living in a metropolitan city. Hence, little is known about how Indigenous children living in regional and rural areas understand and engage with the items. Purpose: The study aims to determine if Indigenous children living in regional and rural areas in Australia understand the items in the PL-C Quest (test content) and if they cognitively engaged with the items (response processes) as intended by the APLF definitions. Methods: The study followed a qualitative descriptive approach. The PL-C Quest includes an orange cartoon bunny carrying out 30 scenarios with accompanying statements. Each scenario has one bunny rabbit doing the activity well and the other bunny not so well. Cognitive interviews were conducted based on verbal probing using Tourangeau’s four-stage cognitive model (comprehension, retrieval, judgment, and response). In the regional town, nine Indigenous children were interviewed one on one in after-school sessions. In the rural town, 12 Indigenous children enrolled in the school programme of a sports provider were interviewed in pairs or small groups. All individual and group interviews were audio recorded and transcribed verbatim. All transcripts were coded using the NVivo12 software. Each cognitive action of Tourangeau’s model, comprehension, retrieval, judgment, and response, became a coding category. Responses coded into each category were further categorised into sub-categories. For instance, ‘Understood as intended’, ‘Partially understood’, and ‘Misunderstood’ were subcategories for comprehension; ‘skills’ and ‘past events and experiences’ were for retrieval; ‘confident and unconfident’ were for judgement; and ‘justify’ and ‘unable to justify’ were subcategories for response category. Once the first author completed the analysis of the children’s responses to items, the other two authors’ part of the data collection confirmed the accuracy of the coding. Findings: Overall, children in both sites understood most of the content of the items as intended. In addition, they could retrieve relevant information when responding to the items. For example, a few children reflected on their ability to play a ball-throwing Indigenous game and carry younger siblings when responding to the items, ‘Object Manipulation’ and ‘Strength’, respectively. Also, most children confidently selected the bunny that represented them more in all 30 items and were able to justify their responses. Conclusion: The study is the first to generate validity evidence for the PL-C Quest when used with Indigenous children in regional and rural Australia. The findings demonstrate that this pictorial scale may be a suitable tool to collect data about the physical literacy of Indigenous children living in regional and rural areas–subject to further testing with a larger population. Future research may provide evidence on other sources of validity. For instance, whether these domains uphold the measured construct, physical literacy (internal structure), with Indigenous children.</p
HLA-DR Matching in Kidney Transplantation:Ethnic Disparities in Clinical Benefit and Policy Implications From a UK Registry Analysis
Get PDFBackgroundThe UK Kidney Allocation Scheme (KAS) prioritizes organ allocation based on HLA mismatches, assigning the greatest weight to HLA-DR compatibility. However, the clinical relevance of this approach across different ethnicities in the era of modern immunosuppression remains uncertain.MethodsWe conducted a retrospective cohort study of 25 094 adult deceased donor kidney transplants in the United Kingdom between 2008 and 2020. Using competing risk Cox regression, we evaluated the impact of individual HLA locus mismatches and grouped mismatch levels (as defined by UK-KAS) on graft survival. Subgroup analyses by ethnicity were performed, and the relationship between HLA mismatches and acute rejection was assessed using logistic regression.ResultsA single HLA-DR mismatch was significantly associated with graft failure (SHR 1.119, 95% CI 1.035-1.211, p = 0.005), while mismatches at the A, B, and DQ loci were not. In subgroup analyses, HLA-DR mismatching was predictive of graft failure in Asian recipients but not in Black recipients. Black patients also exhibited higher rates of mismatching at all loci. DQ mismatches were associated with early acute rejection but did not predict long-term graft failure. Ten-year graft survival was 13% less with one HLA DR mismatch, and 17% less with 2 HLA DR mismatch, in comparison to zero DR mismatch. The four-level HLA mismatch grouping used by UK-KAS stratified risk incrementally, with levels 3 and 4 associated with 13% and 19% higher failure risk, respectively.ConclusionsHLA-DR matching improves graft survival overall but offers limited benefit in Black recipients, likely due to low-resolution typing inadequately capturing immunological compatibility across ethnic lines. The current UK-KAS scoring system may inadvertently disadvantage ethnic minorities by delaying transplantation for matches that confer minimal benefit. Our findings support incorporating ethnicity-specific considerations into kidney allocation policy to promote equity and optimize outcomes
