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Qualitative exploration of gambling harm among UK veterans : normalisation, stigma and postservice escalation
(2026-03) Dekel, Dana; Ekenna, Adanma; Engward, Hillary; Godier-McBard, Lauren R.; Kay, Chris; Kersey, Thomas; Fossey, Matt; Dymond, Simon; Department of Psychology
ObjectiveThis study explored the lived experiences of UK Armed Forces veterans affected by gambling-related harm. It examined how military culture, institutional practices and life transitions shaped gambling behaviours, barriers to help-seeking and the long-term impact on well-being. While quantitative research has documented elevated gambling-related harm among veterans, little qualitative work has examined how veterans themselves understand, experience and navigate gambling harm across military and post-military contexts.DesignReflexive thematic analysis of one-to-one semistructured interviews, covering topics such as the nature of participants’ gambling activities, the impact on their lives, pathways to gambling behaviours and help-seeking.ParticipantsParticipants were UK veterans (n=14), aged 31–60, including one female, from three service branches, all of whom self-identified as having experienced gambling-related harm.ResultsFour interrelated themes were generated: (1) Gambling as normalised in both civilian and military contexts, reinforced by institutional routines and downtime activities; (2) Gambling as an emotional coping mechanism, shaped by institutional norms of stoicism and emotional control; (3) Stigma, silence and structural barriers to help-seeking, including fears of professional repercussions and (4) Escalation postdischarge, driven by isolation, unstructured time, digital gambling access and difficulties adjusting to civilian life. Participants reported concealment, debt and relational breakdowns, with some disclosing suicidal ideation linked to gambling harm.ConclusionsGambling harm among UK veterans is shaped by a complex interplay of cultural, emotional and institutional factors. While gambling opportunities are embedded in military life, systems of support remain inconsistent and often punitive. Gambling remains under-recognised as a serious mental health issue within military and veteran care pathways. Findings highlight the need for stigma-free, culturally informed interventions across the military life cycle, including routine screening, gambling harm education and trauma-informed care.
Self-compassion, depressive symptoms, and well-being : A cross-sectional exploration across athlete status and gender
(2026-02) Einarsdóttir, Fríða Rún; Arnardóttir, Nanna Ýr; Kristjánsdóttir, Hafrún; Belz, Johanna; Kenttä, Göran; Andersson, Mitchell; Tahtinen, Richard E.; Department of Sport Science
Self-compassion is associated with positive mental health outcomes and may buffer against negative self-evaluations and emotional difficulties. Nevertheless, studies among athletes often explore self-compassion in specific groups in isolation (e.g., women athletes) (Röthlin et al., 2019). The aims of this study were to 1) explore whether the relationship between gender and composite scores and specific dimensions of self-compassion (e.g., self-judgement) was moderated by athlete status; and 2) to explore the relationship between different dimensions of self-compassion and self-reported depressive symptoms and well-being among team sport athletes (n = 84, Mage= 22.9 ± 5.0; 57.1 %men) and non-athletes (n = 189, Mage= 35.5 ± 5.9; 32.8 %men). For our first aim, the relationship between gender and self-compassion (including specific dimensions) was not moderated by athlete status. However, regardless of gender, athletes reported significantly higher total self-compassion scores and significantly lower scores on specific dimensions of self-compassion, isolation, and over-identification, than non-athletes. For our second aim, self-judgement was positively associated with depressive symptoms in both athletes and non-athletes. Self-judgment was, however, negatively associated with well-being only among athletes, and isolation was negatively correlated with well-being only among non-athletes.
Ni–Fe-based alloy as oxygen evolving anode for sustainable aluminum production
(2026-03-10) Singh, Kamaljeet; Jamieson, Thomas Luke; Gunnarsson, Gudmundur; Haarberg, Geir Martin; Gallino, Isabella; Busch, Ralf; Magnusson, Jon Hjaltalin; Saevarsdottir, Gudrun; Department of Engineering
Achieving global net-zero carbon targets by 2050 requires the decarbonization of metal production. Molten salt electrolysis, combined with the rapidly expanding renewable energy sector, provides a transformative and sustainable alternative to conventional metallurgical processes and reduces greenhouse gas emissions. Today, aluminum is produced by electrolysis in molten fluoride melts, using consumable carbon anodes for their feasibility, low cost, good conductivity, and efficient reaction kinetics. However, achieving carbon-free aluminum production requires the development of a cost-effective, non-consumable, and efficient oxygen evolving anode (OEA)—a critical challenge that remains unsolved. Here, we demonstrate an earth-abundant and easily processable Ni–Fe-based anode, capable of forming a protective NiFe2O4 oxide, both ex-situ and in-situ, that enhances stability and catalytic activity for OEA. The principal approach to evaluating OEA alloy suitability combines analyzing oxide thermodynamics, investigating oxidation kinetics, and performing extended electrolysis in fluoride melts to elucidate the mechanism of protective oxide formation. By optimizing the Ni/Fe ratio in alloy, we demonstrate reduced alloy corrosion, high purity aluminum production, and efficient oxygen evolution. This method lays the framework for a durable and active Ni–Fe-based OEA, thereby advancing carbon-free sustainable aluminum production.
Nanopore sequencing identifies parent-of-origin specific age-associated methylation changes at imprinted loci in the human genome
(2026-12) Sigurpalsdottir, Brynja; Holley, Guillaume; Sverrisson, Sverrir; Magnusdottir, Droplaug N.; Olafsson, Pall I.; Gylfason, Arnaldur; Magnusson, Olafur; Masson, Gisli; Stefansson, Olafur A.; Halldorsson, Bjarni V.; Department of Engineering
Aging is accompanied by widespread DNA methylation changes, yet their full genomic scope and parent-of-origin dynamics remain poorly understood. Here, we apply nanopore long-read sequencing to 7,284 whole blood samples enabling methylation measurements of 17,959,684 high-quality CpG units. Over 20% of the measured high quality CpG units undergo age-associated changes, predominantly hypomethylation. From these data, we construct a methylation aging clock from 1,373 high-quality CpG units, with median absolute prediction error of 2.43 years. Importantly, phasing the methylation to parental haplotypes enables systematic analysis of age effects in parent-of-origin specific context, uncovering 702 high-quality CpG units with parent-of-origin specific age-association, most of which are located at imprinted genomic regions. At the DIRAS3 locus, we detect age-dependent hypermethylation on the active paternal allele, indicative of attenuation of parent-of-origin specific methylation with age. Together, these findings establish nanopore sequencing as a powerful tool for mapping both genome-wide and parent-of-origin specific signatures of methylation aging and provide evidence that methylation patterns at imprinted loci become progressively altered with age.
One Size Still Does Not Fit All : Configuration Pathways of Environmental, Social, and Governance and Board Diversities for Higher Firm Performances Across One- and Two-Tier Systems
(2026-02) Zhu, Baoying; Brozkova, Dominika; Ahmadov, Tarlan; Durst, Susanne; Prokop, Viktor; Department of Business and Economics
There is an ongoing, albeit uncertain, debate among stakeholders regarding the benefits of environmental, social, and governance (ESG) reporting, reflected in mixed empirical findings on its impact on firm performance. In addition to this reporting, diversity (gender and cultural) on boards, which is strongly promoted at the EU level, has gained increasing importance. However, prior research offers inconsistent results and leaves significant shortcomings regarding how the interaction of this diversity with the ESG pillars affects firm performance across governance structures. This study employs a fuzzy-set qualitative comparative analysis and Refinitiv Eikon data of 554 European Union companies from 2023 to examine configuration pathways that combine gender and cultural diversity with ESG pillars, thus influencing firm performance across different governance forms. Drawing on Upper Echelons and Contingency Theories—enhanced by insights from Resource Dependence and Social Identity Theory lenses—we show that configurations combining gender and cultural diversity with the social pillar of ESG are linked to higher performance within one-tier firms. In two-tier firms, this higher performance is driven by environmental and social ESG pillars combined with cultural diversity. Recognizing that there is no single governance structure in the ESG and diversity context, we offer practitioners guidance on aligning ESG and diversity strategies with their governance architectures, developing governance-sensitive policies, increasing transparency in diversity integration, promoting ESG competency training, and providing targeted incentives.
Knowledge management in the age of generative artificial intelligence – from SECI to GRAI
(2026-02-03) Böhm, Karsten; Durst, Susanne; Department of Business and Economics
Purpose – Generative Artificial Intelligence (GenAI) models are now able not only to recognize complex patterns from large amounts of input data but also to display them in context. This fact invites a critical analysis of the SECI model and its further applicability as an analytical framework for knowledge generation and transfer in organizations. This conceptual paper aims to take the SECI model with the individual SECI phases and analyze how GenAI changes the assumptions and descriptions of the original SECI framework. More specifically, the aim is to propose a revised SECI framework. Design/methodology/approach – This paper aims to contribute to theory development of theories present in the literature. More specifically, it seeks to make a conceptual contribution that draws on one of the four types of conceptual contributions proposed by Deborah J. MacInnis, namely, envisioning, and is based on previous literature and the authors’ thoughts and experiences to propose a revised SECI framework called GRAI, which stands for Generative Receptive Artificial Intelligence. Findings – A better understanding of the further applicability of the SECI framework that arises with the introduction and application of GenAI models is not only relevant to the existing knowledge management (KM) theory but also to organizations. The proposed revised perspective of the SECI model, summarized in the GRAI framework, reflects the use of GenAI technologies in the corporate environment and thus allows the necessary stimulation of a discussion on how KM in general, and knowledge generation, in particular, will be affected and augmented by AI. Originality/value – To the authors’ knowledge, this paper is the first to systematically and comprehensively examine the established SECI framework and its wider applicability in terms of the potential impact of GenAI models on KM practices in organizations. The proposed GRAI framework is seen as a relevant contribution to the further development of KM theory.
It’s Not Easy : Applying Supervised Machine Learning to Detect Malicious Extensions in the Chrome Web Store
(2026-02) Rosenzweig, Ben; Dalla Valle, Valentino; Apruzzese, Giovanni; Fass, Aurore; Department of Computer Science
Google Chrome is the most popular Web browser. Users can customize it with extensions that enhance their browsing experience. The most well-known marketplace of such extensions is the Chrome Web Store (CWS). Developers can upload their extensions on the CWS, but such extensions are made available to users only after a vetting process carried out by Google itself. Unfortunately, some malicious extensions bypass such checks, putting the security and privacy of downstream browser extension users at risk. In this article, we carry out a comprehensive real-world security analysis of malicious extensions in the CWS. Specifically, we scrutinize the extent to which automated mechanisms reliant on supervised machine learning (ML) can be used to detect malicious extensions on the CWS. To this end, we first collect 7,140 malicious extensions published in 2017–2023 and which have been flagged as malicious by Google. We combine this dataset with 63,598 benign extensions published or updated on the CWS before 2023, and we develop three supervised-ML-based classifiers—leveraging both original features as well as techniques inspired by prior work. We show that, in a “lab setting”, our classifiers work well (e.g., 98% accuracy). Then, we collect a new, and more recent, set of 35,462 extensions from the CWS, published or last updated in 2023, with unknown ground truth. We were eventually able to identify 68 malicious extensions that bypassed the vetting process of the CWS. However, our classifiers also reported over 1k likely malicious extensions which may overestimate their true number. Based on this finding (further supported with other experiments and realistic analyses), we elucidate, for the first time, a strong concept drift effect on browser extensions. We also provide factual evidence that commercial detectors (e.g., VirusTotal) work poorly to detect known malicious extensions. Altogether, our results highlight the fact that detecting malicious browser extensions is a fundamentally hard problem which has not (yet) received an adequate degree of attention. This requires additional work both by the research community and by Google itself—potentially by revising their approaches. In the meantime, we informed Google of our discoveries, and we released our artifacts.
High Energy Proximal Tibial Fractures at Landspítali University Hospital 2003-2021 : Háorku nærendabrot á sköflungsbeini á Landspítala 2003-2021
(2026-09-01) Hardarson, Hlynur Breki; Sigurdarson, Hjorturo Vidar; Sigbergsdottir, Audur; Jonsson, Halldor; Ingvarsson, Thorvaldur; Snaebjornsson, Thorkell Snaebjornsso; Department of Engineering
OBJECTIVE: The aim of this study was to investigate the epidemiology of proximal tibial fractures treated at Landspítali National University Hospital following high energy trauma. MATERIALS AND METHODS: This study reviewed patient records of individuals who sustained proximal tibial fractures and were treated at Landspítali between 2003 and 2021. Data on age, sex, mechanism of injury, treatment plan, hospital stay, and outcomes were recorded. Fracture classification was based on evaluation and imaging reviewed in the Agfa system and categorized using the Schatzker classification system. RESULTS: A total of 195 high energy proximal tibial fractures were identified during the study period. The mean age of patients was 42 years, and 62,1% were male. Traffic accidents were the most common mechanism of injury, followed by horse-related accidents and recreational injuries. Most fractures occured in June, and incidence was higher during the summer months. The most common fracture type was Schatzker type II (32,8%), with type I and VI also frequently observed. Surgical treatment was perfomed in 56,9% of cases, most commonly involving internal fixation with plates and screws (used in 74,8% of surgeries). Among those undergoing surgery, Schatzker type VI was the most common. Associated injuries were found in 31,2% of cases, most frequently in patients with complex Schatzker type VI fractures. Only one death occured in relation to the fractures (0,5%). Other complications, such as infections or thromboembolism, were rare. Twelve cases had undergone total knee arthroplasty by the end of the study period. CONCLUSIONS: The incidence of proximal tibial fractures in Iceland (2003-2021) has increased and is comparable to reports from neighboring countries. These injuries are most common in middle-aged men and often result from high energy trauma. Traffic accidents were the leading cause, followed by horse-related and recreational injuries. Most patients who sustained high energy proximal fractures underwent surgery.
Exploring Dynamic Alpha Band Connectivity in Parkinson’s Disease : A Novel Approach to Postural Control Assessment Using the BioVRSea Paradigm
(2026-03) Pescaglia, Federica; Guerrini, Lorena; Gelormini, Carmine; Aubonnet, Romain; Thormar, Gylfi Örn; Di Lorenzo, Giorgio; Jónsson, Halldór; Hassan, Mahmoud; Petersen, Hannes; Minutolo, Vincenzo; Gargiulo, Paolo; Department of Engineering
Parkinson’s Disease (PD) is a neurological disorder characterized by impaired postural control (PC) and balance issues. To date, few studies have explored the relationship between brain activity and responses during specific tasks designed to challenge balance in individuals with PD. Our exploratory research employs an innovative paradigm to assess PC by integrating virtual reality (VR) and electroencephalography (EEG). In the study, 20 individuals diagnosed with PD who self-reported postural instability participated in the BioVRSea paradigm. This paradigm tested their PC using visuomotor stimuli and collected EEG signals to assess brain responses throughout the experiment. The results of the Parkinson’s group were compared with those of 22 age-matched healthy controls (CTR). From the functional connectivity between brain regions, we extracted brain network states (BNSs) using the k-means++ clustering algorithm. These BNSs capture the dynamic organization of brain activity and were compared with canonical resting-state networks (RSNs) to investigate neural alterations in individuals with PD. Six distinct BNSs were identified, with the dorsal attention network (DAN) dominant in five states. A significant reduction in the coverage of BNS2 was observed in PD patients during both the PRE (adjusted p-value = 0.019) and MOV (adjusted p-value = 0.036) phases compared to CTR. This reduced BNS2 coverage suggests impaired visuomotor integration in PD patients during PC tasks. DAN dominance highlights its crucial role in maintaining attentional control during the task. The findings of this study highlight the potential of using brain dynamics as a biomarker of neural dysfunction in PD, especially during specific PC tasks. Altered BNSs, particularly in networks associated with attention and sensorimotor integration, reveal key neural deficits related to PD.
Expedited microwave optimization using variable-fidelity EM analysis and convergence/quality-driven model adjustment
(2026-01-01) Koziel, Slawomir; Pietrenko-Dabrowska, Anna; Department of Engineering
Electromagnetic (EM)-based optimization is imperative for most microwave circuits. This is because designs produced by circuit theory methods require further adjustments to ensure satisfactory performance. Unfortunately, repetitive EM simulations incurred by optimization procedures are associated with considerable expenses. Expediting the process is essential to reduce the time span of design cycles and time-to-market in the case of industrial products. One possibility is utilization of variable-resolution EM simulations; however, available frameworks typically employ two discrete levels of fidelity (coarse/fine) combined with often sophisticated model correction methods. This paper proposes an alternative approach to accelerated microwave component tuning. Our methodology involves a continuous spectrum of EM simulation resolutions, which are controlled using the convergence and design quality indicators of the underlying optimization routine. A management scheme adjusting the model resolution is developed to utilize the lowest usable resolution at the search process onset, which is continuously increased as the algorithm approaches convergence and the objective function reaches satisfactory levels. The final stages are carried out with high-fidelity resolution to ensure accuracy. Verification experiments conducted using three microstrip circuits demonstrate over sixty percent of average savings over the reference (single-resolution) gradient-based routine, and noticeable and consistent acceleration regarding several state-of-the-art expedited versions. Selected designs are experimentally validated.
Evaluating the Reliability and Validity of Predictive Anthropometric Equations for Estimating Fat Mass, Lean Mass and the Role of Maturity Offset in Lean Mass Prediction Within Professional, Academy Soccer Players from the United Kingdom
(2026-03) Efstathiou, Elena; Wilson, Laura J.; Dickinson, Brent; Curtis, Christopher; Department of Sport Science
The reliability and validity of anthropometric equations remain uncertain in young athletes experiencing biological maturation. This study assessed the reliability and validity of anthropometric equations against dual-energy X-ray absorptiometry (DXA)-derived fat mass (FM) and lean mass (LM) values and examined the influence of maturity offset within academy soccer players. Twenty-five male academy soccer players (age: 18.6 ± 0.8 years, height: 182.7 cm ± 5.9 cm, BM: 79.3 kg ± 7.6 kg) completed skinfold and DXA assessments. FM and LM were estimated using commonly adopted anthropometric equations. Reliability and validity were assessed. Linear regression examined the influence of maturity offset. Acceptable agreement for the equations of Wilmore & Behnke and Oliver et al. for LM and FM was observed (FM; ICC: 0.858–0.891, CV%: 8.1–8.8 ± 4.6–6.4, LoA: 2.62–3.06 to −1.33–−1.62, ES: 0.27–0.47, Z = −2.257–−3.150; LM: ICC: 0.886–0.905, CV%: 2.9–3.3 ± 1.3, LoA: 5.17–5.62 to 0.54–0.78, ES: 0.42–0.48, both p < 0.001). Bland–Altman inspection showed mean bias and wide LoA for all equations. Maturity offset modestly predicted LM for all equations. Observed anthropometric equations have limited validity vs. DXA-derived FM and LM in academy soccer players. Maturity offset warrants consideration for maturity-sensitive, population-specific equations to avoid systematic errors.
Evaluating the Efficacy of Electronic Screening, Brief Intervention, and Referral to Treatment (e-SBIRT) for Gambling : An Online Pilot Randomised Trial
(2026-10) Wright, Simon; Quigley, Martyn; Dymond, Simon; Department of Psychology
Objectives: To investigate the efficacy of electronic screening, brief intervention, and referral to treatment (e-SBIRT) at improving gambling outcomes and increasing help-seeking. Methods: We conducted a two-arm, randomised online pilot trial (n = 83) comparing an e-SBIRT intervention with an active control over 12 weeks. The brief intervention was informed by motivational interviewing and incorporated personalised normative feedback, information provision, and relapse-prevention components. Eligible participants were aged 18 or older, resided in the UK and had scores indicating at least moderate severity gambling. Results: Participants (54 [65.1%] male; mean [SD] age = 40.58 [12.75] years, mean [SD] PGSI = 7.16 [5.58]) in the e-SBIRT and control conditions showed improvements in gambling harms (p = 0.033) and perceived ability to control gambling (p = 0.029). No significant effects of condition assignment or condition x time interactions were observed. However, exploratory analyses of individual model coefficients suggested greater improvement in perceived ability to control gambling among participants receiving e-SBIRT at 12 weeks (p = 0.043). Exploratory analyses also suggested higher rates of help-seeking at 12-week follow-up among participants receiving e-SBIRT. Conclusion: Overall, e-SBIRT did not demonstrate clear advantages over assessment and information provision alone. Further research should prioritise refining intervention components and evaluating SBIRT approaches in settings that better reflect its opportunistic delivery model.
Consumer-Based Retailer Brand Equity Across Different Shopping Needs : Experimentally Analysing Sub-Brands
(2026-02) Sigurdsson, Valdimar; Larsen, Nils Magne; Folwarczny, Michał; Maulana, Huda K.; Fagerstrøm, Asle; Menon, R. G.Vishnu; Department of Business and Economics
The current research extends the consumer-based retailer brand equity literature by examining consumers' willingness-to-shop at various sub-brands during different types of shopping trips. We experimentally tested the predictive validity of a modified scale using sub-brands from two major retailer brands. Study 1 focused on United Kingdom consumers and examined sub-brands of Tesco. The findings revealed a strong correlation between the scale's index and consumers' willingness-to-shop for both major and minor shopping trip types, as well as at Tesco Express and Extra sub-brands. The scale's eight facets were nearly always significant across these conditions. Study 2 was conducted on consumers from the United States, and used Walmart's sub-brands: Neighborhood Markets and Supercenters. The findings replicated those of Study 1. However, in Study 2 all eight facets of the scale were significant across all conditions. The experimental data confirms the academic relevance of the scale as a single-factor measure across different consumer shopping goals, supporting its practical application as a standalone measurement for assessing retailer brand portfolio equity. Furthermore, all facets are essential and can provide meaningful insights for managers. The data also show that consumer-based retailer brand equity can mediate the effects of different shopping trip types when there is a large difference in willingness-to-shop at the retailer sub-brand level.
Does the Intent Match the Output : Aligning Development Goals With Training Load in Youth Basketball
(2026-03) Lever, Jonathon R.; Duffield, Rob; Murray, Andrew; Bill, Holland A.; Bartlett, Jonathan D.; Fullagar, Hugh H.K.; Department of Sport Science
This study investigated the alignment between external training load metrics and coach-prescribed development goals in an elite youth basketball setting. External training load data from training drills were collected over two years from 25 elite male youth basketball players in a full-time residential academy. At the start of each term, coaches developed and assigned individual developmental goals (IDGs) for each player. Using inductive thematic analysis, these IDGs were retrospectively grouped into four overarching development goal categories (defensive, offensive, skill, and physical) and 16 specific goal types (e.g., cutting, shooting, and load tolerance). Separately, external load metrics were recorded during all on-court training sessions using Catapult Vector S7 devices. To align IDGs with external load metrics, two multinomial logistic regression models were developed to classify (1) development goal category and (2) specific goal type (SGT) using per-minute external load metrics. Both models achieved 66% classification accuracy (Kappa = 0.60). Key predictors, such as high-intensity deceleration counts, vertical PlayerLoad, and high-speed running distances, were retained in both models following stepwise selection. Model performance was strong, with large reductions in AIC (ΔAIC = 1224.1 and 2540.7, respectively), demonstrating that coach-assigned IDGs were associated with distinct external load profiles. Additionally, accumulated training time differed significantly across specific goal types, reflecting systematic variation in emphasis across the season. These findings demonstrate that external training load metrics reflect the structure of coach-assigned development goals, offering a data-driven framework to evaluate alignment between training design and physical demands in youth basketball.
Determining Cluster-Specific Differences in the Number of Days Required to Reliably Predict Habitual Physical Activity : Intraclass Correlation Resampling Analysis
(2026) Murphy, Conor Jordan; Jouan, Gabriel M.; Friðgeirsdóttir, Katrin Y.; Islind, Anna Sigridur; Saavedra, Jose M.; Óskarsdóttir, María; Arnardóttir, Erna Sif; Department of Engineering; Department of Sport Science; Department of Computer Science
Background: Previous research has attempted to determine the minimum number of days of accelerometry required to reliably reflect an individual’s physical activity. However, human behaviors on a day-to-day basis can be highly variable. As a consequence, the number of days required to reliably predict habitual physical activity is dependent on the variability that exists within an individual. There is a concern that adopting generic recommendations from previous research could provide unreliable estimates by failing to represent individuals with specific physical activity patterns. Objective: The main aim of this study was to identify clusters of individuals with distinct physical activity patterns and to determine if the number of days of accelerometry data required to reliably estimate short- (7 days) and medium-term (28 days) physical activity differed between each unique cluster. Methods: Accelerometry data were retrieved from 2 independent research studies. Participants during each study had their physical activity recorded using a Withings Scanwatch (Withings Health Solutions). Following a data eligibility process, agglomerative hierarchical clustering was used to identify clusters of individuals based on their physical activity. The clusters were determined using 4 dimensions; mean, SD, skewness, and kurtosis of the step count data. Intraclass correlation coefficients (ICCs) of step count were then calculated within each physical activity cluster. A series of ICCs were computed by separately comparing the average step count across the full periods (7 and 28, for the short- and medium-term analysis, respectively) to a series of averaged subsamples (ranging from 1-6 days and 1-27 days, for the short- and medium-term analysis, respectively). For each subsample, 500 random combinations were generated and compared, providing a distribution of ICCs for each subsample. An ICC of ≥0.80 identified when the subsample of days was sufficient to achieve appropriate reliability. Results: Of 258 participant datasets, 149 were eligible for the short-term analysis and 64 were eligible for the medium-term analysis. Following agglomerative hierarchical clustering, 4 and 3 clusters of sufficient size (n≥12) were identified in the short-term and medium-term analyses, respectively. When considering the short-term analysis, to achieve a mean ICC score greater than or equal to 0.80, using all randomized combinations, the number of days ranged from 2 to 6 days depending on the physical activity cluster. For the medium-term analysis, the number of days required to achieve a mean ICC score greater than or equal to 0.80 ranged from 6 to 11 days. The short-term analysis clusters displayed more diversity in physical activity patterns than the medium-term analysis. Conclusions: Physical activity patterns influence the number of days required to estimate habitual physical activity. Thus, to avoid unreliable estimates of physical activity, which could significantly impact the interpretation of results, researchers should be mindful of the physical activity patterns of their sample before adopting generic recommendations.
Covenant Prices of U.S. Corporate Bonds
(2026-09) Handler, Lukas; Jankowitsch, Rainer; Weiss, Patrick; Department of Business and Economics
In this paper, we analyze the key drivers of bond covenant prices by employing a novel measurement approach based on secondary market data. We find that covenant prices vary significantly over time and are associated with market-wide credit risk, volatility, and macroeconomic variables. Apart from the time-series dynamics, there is also significant variation across bond and firm characteristics. In particular, covenant prices increase with the riskiness of bonds and are higher for firms that have more growth options, more tangible assets, and are smaller. Furthermore, we document a positive correlation between the prices of covenants and their subsequent inclusion rates.
Coping, Civilian Transition, and Gambling Harm Severity in UK Armed Forces Veterans
(2026-03) Ekenna, Adanma; Dekel, Dana; Engward, Hilary; Godier-MacBard, Lauren; Kay, Christopher; Kersey, Thomas; Fossey, Matt; Dymond, Simon; Department of Psychology
Veterans are prone to experiencing both mental health challenges and harm from gambling, yet little is known about the psychosocial factors that may increase risk. This study examined predictors of gambling harm severity in a sample of UK Armed Forces veterans with a focus on coping styles and reintegration into civilian employment. A cross-sectional survey was conducted among 414 former personnel using validated measures of gambling behavior, coping, and mental health symptoms including alcohol use. Of the 226 (54.6%) who had gambled in the past year, 3.1% had scores suggestive of problem gambling. Results showed that 46% of participants exhibited symptoms suggestive of posttraumatic stress disorder (PTSD), while 8.4% reported severe anxiety, 10.2% severe depression, and 11.1% high-risk alcohol use. Gambling harm severity was positively predicted by difficulties adapting to civilian employment and maladaptive coping strategies such as self-blame and substance use, while use of informational support was found to be protective. Given higher rates of primary care engagement among veterans, routine screening for gambling-related harm in such settings may improve early detection and intervention. The findings underscore the need for integrated mental health services that consider both psychological and social determinants of gambling harm severity in veterans during the military-to-civilian transition.
Constructing a corporate governance index for SMEs : How it mediates the access to finance-performance relationship
(2026-03) Bilyay-Erdoğan, Seda; Demir, Ender; Cevheroğlu Acar, Merve Gizem; Ozkan, Irem; Department of Business and Economics
SMEs play a vital role in employment, innovation, and competitiveness worldwide, yet their governance structures remain underexplored in academic research. Existing studies on corporate governance predominantly focus on large publicly traded firms, leaving a gap in our understanding of how governance mechanisms operate in SMEs. To fill this gap, the primary purpose of this study is to introduce a novel and comprehensive corporate governance index tailored specifically to SMEs. Using stratified sampling, we conducted a structured survey of 469 SMEs across diverse sectors and firm sizes in Türkiye. This index comprises six subdimensions: board structure, family involvement, female participation, digitalization, corporate accountability, and succession, and its internal validity is confirmed with Cronbach's alpha values above 0.70 for the overall index and most subindices. The second purpose of this study is to investigate the relationship between access to finance and SME performance, emphasizing the mediating role of corporate governance. Using cross-sectional regression analysis, our results show that access to finance significantly improves SME performance. We also find that corporate governance not only enhances performance directly but also mediates this positive association. To the best of our knowledge, this is the first study to demonstrate that access to finance influences SME performance through both direct and indirect channels. Overall, our findings highlight that effective governance structures are essential to maximize the benefits of access to finance. This finding underscores the role of institutional and managerial factors in enhancing firm-level competitiveness by enabling SMEs to leverage access to finance and governance practices to achieve sustainable growth.
A Rotation-Controlled Anisotropic Hourglass Metasurface for Multiband Reflective Linear-to-Circular and Cross- Polarization Conversion
(2026) Nasir, Muhammad; Koziel, Slawomir; Pietrenko-Dabrowska, Anna; Department of Engineering
This paper presents and experimentally validates a multifunctional anisotropic metasurface (MS) that exhibits linear-to-linear (LTL) reflective cross-polarization (RCP) and circular polarization conversion (CPC) responses across multiple frequency ranges. The proposed MS integrates a single-layer design consisting of 45° oriented truncated circular ring and an hourglass-like structure, providing four LTL-RCP conversion bands (2.41 - 2.48, 3.16 - 3.46, 5.80 - 6.59, and 11.64 - 13.75) GHz with polarization conversion ratio (PCR) exceeding 95%, and seven CPC bands (2.33 - 2.38, 2.55 - 2.99, 3.69 - 5.37, 7.13 - 10.92, 13.95 - 14.25, 14.93 - 15.17, and 15.31 - 15.56) GHz with the axial ratio (AR) less than 3 dB, covering the S-, C-, X-, and Ku-bands. By only adjusting the angle of the hourglass structure at 15° within the same structure, LTL-RCP with PCR greater than 95% is realized in the frequency bands from 13.71 to 14.64 GHz, along with ≤ 3 dB of AR is achieved at four additional CPC bands at (2.20 - 2.36, 2.95 - 8.41, 10.84 - 12.30, and 14.84 - 15.06) GHz. The polarization conversion mechanisms are explained through detailed surface-current distributions analysis and full-wave electromagnetic (EM) simulations. Furthermore, the proposed concept is validated through the measurements of the fabricated prototype consisting of 8× 13 -unit cells. The measurement results are in excellent agreement with the simulation predictions. The proposed MS design demonstrates a simple yet effective solution for achieving tunable multi-band polarization manipulation without structural modification, making it suitable for advanced EM communication applications.
A reconfigurable array and MIMO antenna for 18 GHz and 28/38 GHz applications
(2026-01-15) Paşalıoğlu, Halil; Wang, Lulu; Bakır, Mehmet; Paul, Liton Chandra; Tetik, Erkan; Karaaslan, Muharrem; Department of Engineering
This study introduces the development and experimental verification of a reconfigurable array and MIMO antenna system designed to operate at 18 GHz, 28 GHz, and 38 GHz—frequency bands that are critically important for next-generation wireless communication technologies, including 5G and beyond. The reconfigurability of both antenna types is achieved through the integration and dynamic control of PINs, allowing for the selective activation and deactivation of specific segments defined by designated geometric parameters. Simulation and experimental results of the proposed antennas, including scattering parameters and radiation patterns, are thoroughly investigated. Simulation results indicate that the array antenna achieves bandwidths of 0.80 GHz at 18 GHz, 2.62 GHz at 28 GHz, and 7.91 GHz at 38 GHz, respectively. This performance encompasses all FCC-designated millimeter-wave 5G bands. The MIMO antenna demonstrates a transmission coefficient below −25 dB for both PIN diode states, significantly exceeding the −10 dB isolation threshold. This result confirms the antenna's suitability for operation across the 18 GHz, 28 GHz, and 38 GHz frequency bands. Subsequently, the fabrication of both antennas was undertaken, and the measured parameters exhibited good agreement with the simulation results. The reconfigurable array antenna exhibits beam steering and pattern diversity capabilities essential for overcoming propagation challenges at millimeter-wave frequencies, while the MIMO antenna system leverages spatial multiplexing and diversity to enhance data rates and link reliability. The presented antenna designs offer versatility for future wireless systems and hold considerable promise for a multitude of advanced applications, including high-capacity data transmission and radar systems operating within the 5G bands.

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