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Varanleg URI fyrir þennan undirflokkhttps://hdl.handle.net/20.500.11815/5667

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Niðurstöður 1 - 20 af 532

The development, implementation and validation of an objective match scoring system for elite netball
(2025) Butterworth, Andrew; Hamblen, Andrew; O’Donoghue, Peter; Department of Sport Science
This study created and empirically validated an objective match scoring system for the dynamic and tactically rich sport of elite netball. Vast data was captured from all matches (488) played over five-seasons in the UK Netball Superleague. This was ordered into evenly weighted segments for each performance indicator, with each segment assigned a 0 to 10 value on a sliding scale, with the lowest segmented performances awarded a 0, and the highest a 10. Next, individual performance indicators for both teams in all 308 matches from seasons 2021, 2022 and 2023 were calculated an out of ten score, based on which segment they fell within. A resultant out of ten score for the overall match performance of each team was then computed, showing its objective strength. Use of this system was then implemented within elite coaches pre- and post-match analysis processes, with mixed methods utilised to ascertain the empirical validity in practice. Quantitative analysis concludes that the system accurately scores the outcome of matches with statistical significance, whilst qualitative data confirms the usefulness for elite coaching practice, specifically as an aid to previewing and reviewing performances. We conclude that the tool is an objective, trustworthy addition to the coaching process.
Pre-trained deep learning space mapping with intermittent model enhancement for fast multi-fidelity microwave design optimization
(2026-09-14) Koziel, Slawomir; Pietrenko-Dabrowska, Anna; Department of Engineering
Parameter tuning is essential in the development of microwave devices. In recent years, a growing interest in formal optimization methods has emerged, driven by their ability to simultaneously adjust multiple decision variables, even under constraints. Their disadvantage is their high computational cost, which is a serious obstacle to the optimization of electromagnetic (EM) models. This difficulty can be alleviated using multi-fidelity simulations. Problem-independent approaches rely on low-fidelity models constructed through coarse-discretization EM analysis (in contrast to problem-specific equivalent network representations), where a critical factor is the appropriate model correction strategy. This paper introduces a versatile deep-learning space mapping (DLSM) strategy that leverages a reusable pre-trained neural network surrogate. The non-parametric DLSM model implements multi-point response correction, applied independently to the real and imaginary components of relevant S-parameter responses. Furthermore, it is trained as a function of the problem's decision variables and response interrelations. It is embedded in a gradient-based optimization loop, where it is locally retrained using intermittent high-fidelity simulations and sample weighting to place greater emphasis on the neighborhood of the current solution. Comprehensive verification of the procedure involving three planar circuits underscores its competitive efficacy, with a mean running cost of 16 high-fidelity simulations and relative savings over the baseline algorithm up to 87%. Meanwhile, consistent results obtained for multiple scenarios targeting diverse performance specifications corroborate DLSM reusability and applicability across broad ranges of operating conditions.
What Static Connectivity Misses : Dynamic Alpha-Band Brain Network States in First-Episode Psychosis
(2026-09-11) Aubonnet, Romain; Hassan, Mahmoud; Gargiulo, Paolo; Seri, Stefano; Di Lorenzo, Giorgio; Department of Engineering
This study investigates resting-state EEG alpha-band connectivity in first-episode psychosis (FEP) using a novel dynamic connectivity pipeline and examines its relationship with cognitive functioning and psychopathological scores. Data from 78 individuals with FEP and 60 healthy controls (CTR) were analyzed. Source estimation was performed using eLORETA, and connectivity was quantified with the weighted phase-lag index. Static connectivity matrices were assessed using graph theory and edge-wise metrics. Dynamic connectivity matrices were clustered into five distinct brain network states (BNS) using a modified k-means algorithm, from which temporal and graph theory metrics were extracted. Static connectivity metrics revealed lower alpha connectivity in FEP than in controls. The dynamic approach identified reduced variability in the characteristic path length within the default mode network–associated BNS 1 in FEP, suggesting diminished adaptive modulation of functional integration. Subgroup analysis by medication status uncovered distinct BNS signatures for medicated and unmedicated FEP. BNS metrics were correlated with social cognition measures in CTR and with positive formal thought disorder in FEP, whereas static metrics showed no such associations. These findings suggest that relative to static connectivity metrics, dynamic connectivity provides non-redundant information and underscores the impact of medication on neural dynamics in psychosis.
Public perceptions of gambling in the UK Armed Forces : understanding stigma via qualitative inquiry
(2026-09-09) Smith, Jessica; Treacy, Samantha; Dymond, Simon; Torrance, Jamie; Department of Psychology
Background: Existing research has identified elevated public stigma toward Armed Forces personnel experiencing gambling-related harm. However, the reasoning underlying these perceptions remains poorly understood. Qualitative research can explore the drivers of such stigma and inform potential approaches to reduce it. Methods: A qualitative online survey was conducted with UK-based civilian respondents (N = 52) recruited via Prolific. Participants were screened to ensure they could meaningfully discuss gambling and military life. Open-ended questions invited participants to reflect on perceived risks and discuss attitudes toward gambling in both military and civilian contexts. Responses were analyzed using thematic analysis. Results: Four overarching themes with eleven sub-themes were identified: (1) Constructing the Unknown, (2) Perceived Drivers of Gambling within Military Culture, (3) Locating Responsibility and (4) Responding to Military Gambling. Conclusion: Findings suggest that public interpretations of military gambling-related harm were shaped by tensions between gambling and an idealized military identity, alongside negotiated understandings of responsibility across individual, institutional, and societal levels.
Motivators of Sexual Violence Disclosures and Mental Health : A Mixed Methods Investigation
(2026-09-04) Sigurvinsdottir, Rannveig; Thorvaldsdóttir, Karen Birna; Jónsdóttir, Erla Katrín; Ásgeirsdóttir, Bryndís Björk; Department of Psychology
The aim of this mixed methods study was to examine motivators and characteristics of sexual violence disclosures and relationships with mental health. A representative national sample of male and female Icelandic adult survivors (N = 473) took part in a survey. Disclosure was common, especially among women, and psychological symptoms were greatest among late disclosers. Motivators of disclosure included violence itself, trauma and recovery, and social context and movements. Social context and movements disclosures related to lower psychological symptoms. Further research is needed to understand how disclosing related to social movements, such as #MeToo, could potentially confer mental health benefits.
Temporal dynamics of EEG microstates during postural control in Parkinson's disease
(2026-09-01) Gelormini, Carmine; Guerrini, Lorena; Pescaglia, Federica; Maruotto, Ida; Aubonnet, Romain; Jónsson, Halldór; Petersen, Hannes; þormar, Gylfi Örn; Di Lorenzo, Giorgio; Hassan, Mahmoud; Gargiulo, Paolo; Department of Engineering
Parkinson's disease (PD) is a progressive neurodegenerative disorder characterised by motor impairments extending to balance and postural regulation. Although EEG abnormalities in oscillatory activity and functional connectivity are well documented in PD, large-scale brain dynamics during tasks directly engaging postural control remain poorly understood. To address this gap, we examined EEG microstate organisation during the BioVRSea virtual-reality postural-control task in early-stage PD patients (n = 30) and matched healthy controls (HC; n = 26). EEG microstates, brief quasi-stable scalp topographies representing global neural states, provide a robust framework for characterising the rapid temporal structure of whole-brain activity. Although task-based microstate approaches exist, applications to PD remain limited and largely confined to resting-state research. Topographical analyses revealed pronounced between-group differences in microstates D and E, whose group-averaged maps in PD diverged markedly from canonical configurations. Because these maps were not topographically equivalent between groups, comparisons of temporal parameters were restricted to the comparable microstates A–C. Across all task phases, PD patients showed increased duration and coverage of microstates A and B. Transition-probability analysis, likewise restricted to A–C, indicated different trajectories across phases in PD and HC. A single significant Group × Phase interaction emerged for A→C: the largest between-group difference occurred during the POST-movement phase, when PD showed a higher probability than HC. For the remaining transitions, no phase-dependent differences emerged within PD. Because patients were assessed ON medication and clinical or behavioural correlates were unavailable, these findings represent candidate task-state EEG microstate alterations requiring validation, rather than established disease-specific markers.
igraph 1.0 enables fast and robust network analysis across programming languages
(2026-08-04) Antonov, Michael; Csárdi, Gábor; Horvát, Szabolcs; Müller, Kirill; Nepusz, Tamás; Noom, Daniel; Salmon, Maëlle; Traag, Vincent; Welles, Brooke Foucault; Zanini, Fabio; Department of Computer Science
Networks or graphs are widely used across the sciences to represent relationships of many kinds. The igraph (https://igraph.org) software library supports graph construction, analysis, and visualisation, combining fast and robust performance with a low entry barrier. igraph pairs a fast core written in C with beginner-friendly interfaces in Python, R, and Mathematica. After twenty years of development, igraph 1.0 has been released, enabling public access to a robust and stable network analysis with over a million monthly downloads. Thanks to its cross-language design, igraph delivers both speed and flexibility: it can handle billions of edges, supports interactive plotting, integrates with notebooks, facilitates conversions to and from other network libraries, includes a rich library of graph layout and community detection algorithms, and has a detailed documentation including non-English translations. Modern testing features such as continuous integration, address sanitizers, stricter typing, and memory-managed vectors have also increased robustness. Hundreds of bug reports have been fixed and a community forum has been opened to connect users and developers. Specific effort has been made to broaden use and community participation by women, non-binary people, and other demographic groups typically underrepresented in open source software.
When war moves oil : Energy dependence and global equity responses to the 2026 Iran conflict
(2026-07-27) Kaczmarek, Tomasz; Demir, Ender; Rouatbi, Wael; Zaremba, Adam; Department of Business and Economics
We provide, to the best of our knowledge, the first systematic cross-country analysis of global equity market reactions to the U.S.-Israeli military operation against Iran on February 28, 2026, using daily returns from 67 countries. Stock prices declined materially, signaling a repricing of geopolitical risk. Cross-country heterogeneity reflects energy exposure: fuel exporters experienced smaller losses, while importers suffered larger declines. Nuclear capacity was associated with smaller losses, consistent with diversification benefits. Standard macroeconomic and geopolitical variables have limited explanatory power. Overall, the results suggest that energy markets are a central transmission channel for geopolitical shocks and point to the role of energy independence in financial resilience.
Evaluating the quality of systematic reviews and meta-analyses published in behaviour analysis journals : An umbrella review
(2026-06-26) May, Richard; Campbell, Olivia; Apanasionok, Magda; Molina, Josh; Seel, Christopher; Totsika, Vaso; McTiernan, Aoife; Tennyson, Alan; Grindle, Corinna; Dymond, Simon; Department of Psychology
High-quality systematic reviews and meta-analyses are essential for translating evidence into practice. We conducted an umbrella review to evaluate the methodological quality of systematic reviews and meta-analyses published in the field of behaviour analysis up to and including 2023. Eligible studies were identified through targeted searches of seven behaviour analysis journals using APA PsycINFO. Quality was assessed using the Assessing the Methodological Quality of Systematic Reviews (AMSTAR 2) and Revised AMSTAR (R-AMSTAR) instruments. Temporal trends were analysed using Bayesian multilevel regression. The protocol was preregistered on the Open Science Framework (doi.org/10.17605/OSF.IO/U38Z4). We identified 64 reviews (16 of which included a meta-analysis), all of which were rated as ‘critically low’ quality using the AMSTAR 2 criteria. Methodological shortcomings included absent protocol registration, inadequate risk of bias assessment, and failure to assess publication bias. Mean R-AMSTAR adherence was 43.8% (range 11–66%) and increased by 1.08% per year (population-level average marginal effect from the multilevel logistic model (95% CI [0.59, 1.58]), indicating robust methodological improvement over time. Currently, many systematic reviews and meta-analyses in behaviour analysis do not yet meet contemporary standards of methodological rigour. Enhancing the quality, transparency, and consistency of evidence synthesis is vital if systematic reviews are to meaningfully inform practice.
Unraveling physical performance over time in hospitalized older patients with walking limitation : the role of ultrasound-derived vastus lateralis muscle thickness
(2026-06-25) Phillip, Jeppe Grabov; Oddsson, Hjalti Rúnar; Ryg, Jesper; Suetta, Charlotte; Masud, Tahir; Minet, Lisbeth Rosenbek
Acute hospitalization is a critical stressor that often leads to functional decline in older patients, highlighting the need for simple markers to identify at-risk individuals. Ultrasound is a feasible bedside tool for muscle mass assessment and has been proposed as a marker of physical function, but its prognostic value remains unclear. This study aimed to explore the association between ultrasound-derived muscle thickness (US-MT) and physical performance over time—gait speed (GS) and 30-s sit-to-stand (30s STS)—and selected clinical outcomes. In this prospective cohort study conducted in a geriatric department, adults aged ≥ 65 years with admission-related walking limitations were assessed at admission, discharge, 1 month, and 3 months. US-MT of the vastus lateralis was assessed at admission using ultrasonography. Longitudinal associations between US-MT and GS and 30s STS were examined using mixed-effects models. Associations with length of hospital stay (LOS), 3-month falls incidence, and 3-month mortality were examined using regression models. Among 243 participants, GS and 30s STS increased from admission to follow-up. Greater admission US-MT was modestly associated with faster GS in women (0.037 m/s; 95% CI 0.022–0.051) and with better 30s STS performance across sexes (IRR 1.24; 95% CI 1.00–1.53) across all time points. US-MT was not associated with trajectories of physical performance or with LOS, falls, or mortality. These findings suggest that admission US-MT may provide complementary bedside information on physical performance level, rather than serving as a standalone marker of recovery or clinical prognosis. ClinicalTrials.gov:
The I of the Storm : Entrepreneurial Action as Practical Reason
(2026-06-15) Dimov, Dimo; Garmann Johnsen, Christian; Department of Business and Economics
In blurring the distinction between third- and first-person perspectives of entrepreneurial action, current theories fail to differentiate the knowledge domains of scholars and entrepreneurs. We develop a shift in theorizing entrepreneurial action, focusing on a self engaged in practical reasoning. In our framework, entrepreneurial action is what makes one an entrepreneur—there is no entrepreneur prior to it. We elucidate entrepreneurial action as implicating a complex intention, with the entrepreneurial self as the cause of action. Entrepreneurship thus entails time-extended, social agency: entrepreneurs act both in the present and for the future. By regaining the first-person footing of entrepreneurial action theory, we open new avenues for theoretical development.
When Disaster Hits, Governance Splits : Different Effects on Domestic and Inbound Tourism
(2026-06-09) Er, Selahattin Tolga; Demir, Ender; Department of Business and Economics
While natural disasters have the potential to disrupt tourism demand, evidence on their impacts is mixed. This study positions governance quality as a central factor in explaining these divergent outcomes, examining its moderating role in the relationship between natural disasters and inbound and domestic tourism. Using panel data from OECD countries, we show that governance quality reduces, and in many cases reverses, the negative effects of disasters on inbound tourism, with effects persisting into the following year. In contrast, domestic tourism increases upon disasters in countries with low-governance quality. This moderating effect for domestic tourism is evident only for geological disasters, suggesting that governance matters for sudden-onset events. Overall, our results indicate that governance quality reshapes the tourism-disaster relationship, sustaining inbound tourism when strong and resulting in increased domestic travel when weak, underlining the differential effects of governance quality across inbound and domestic tourism.
From the Court to the Laboratory : The Scientific Evolution of Handball through Global Research and Performance Outcomes
(2026-05-28) Saavedra, Jose M.; Porgeirsson, Sveinn; Hatzimanouil, Dimitris; Escalante, Yolanda; Department of Sport Science
The objectives of this study were: (i) to analyze the evolution in the number of articles published on handball and the citations received; (ii) to determine whether there is a relationship between scientific production and the number of medals won in the Olympic Games and World Championships; (iii) to identify the research topics with the highest publication rates in handball; and finally, (iv) to identify the most cited articles, as well as the journals and countries that published the most on handball. Articles published between January 1, 1980, and December 31, 2024, were retrieved from the Web of Science Core Collection database. For each article, the following information was analyzed: authors; journal (year, volume, issue, pages, DOI); institution and country; funding agency; number of citations; and research topic. Absolute values and percentages were presented for articles and citations per year. Regression analyses calculated the coefficients of determination for the relationships between the number of articles and year, citations and year, and medals and publications by country. A total of 1,412 articles were analyzed. Significant relationships were found between year and number of articles (R2=0.6625p<0.001), year and citations (R2=0.6697p<0.001), and publications and medals by country (R2=0.1575p<0.01). The four countries that published the most articles were Spain, Germany, Norway, and Brazil. The main research topics were physical capacities – measurements, injuries and sports medicine, and physiological responses and adaptation (training programs). Five journals accounted for 19% of all publications.
Reducing Intrusive Trauma Memories Using a Brief Mental Imagery Competing Task Intervention : Case Series of Trauma-Exposed Women in Iceland
(2026-05-15) Thorarinsdottir, Kristjana; Holmes, Emily A.; Hardarson, Johann; Agustsdottir, Freyja; Kanstrup, Marie; Singh, Laura; Hauksdottir, Arna; Halldorsdottir, Thorhildur; Gudmundsdottir, Berglind; Thordardottir, Edda Bjork; Valdimarsdottir, Unnur; Bjornsson, Andri; Department of Psychology
Background: There is a need for scalable and simple interventions for trauma-exposed people. In this case series, we built on our previous case study and case series findings and further explored the use and potential effectiveness of a brief novel intervention to reduce the number of past intrusive memories of trauma. The imagery competing task intervention consists of a memory reminder and the visuospatial task Tetris played with mental rotation, targeting 1 intrusive memory at a time. Here, we test remote delivery of the intervention, including guidance from researchers without specialist mental health training, in a sample of women in Iceland with current intrusive memories from trauma. Objective: In a case series of trauma-exposed women, we aimed to explore whether this brief novel intervention reduces the number of established intrusive memories (primary outcome) and improves general functioning and symptom reduction in posttraumatic stress, depression, and anxiety (secondary outcomes). The acceptability of the intervention along with adaptations, that is, delivery by psychology students without specialist mental health training and digital delivery, was explored. Methods: Participants (N=8) monitored the number of intrusive memories from an index trauma (occurring 3‐16 years previously) in a daily diary at baseline, during the intervention, and postintervention at 1-month and 3-month follow-ups. The intervention was delivered digitally with guidance from clinical psychologists or psychology students. A repeated AB design was used (“A”: preintervention baseline, “B”: intervention phase). Intrusions were targeted one by one, creating repetitions of an AB design (ie, length of baseline “A” and intervention “B” varied for each memory). Results: The number of intrusive memories reduced for all participants from the baseline phase compared with the intervention phase, although the reduction was minimal for 2 participants (6.3%‐93%). The number of intrusive memories continued to reduce for 6 out of 8 participants (58%‐100% reduction at 1-month follow-up; 72%‐100% reduction at 3-month follow-up). Symptoms of posttraumatic stress, depression, and anxiety were reduced for most participants postintervention and continued to decrease during the follow-up periods. Functioning was improved for 7 of the 8 participants from baseline to postintervention and continued to improve at the follow-up assessments for 3 participants. The intervention delivered digitally and partly by students was perceived to be an acceptable way to reduce the frequency of intrusive memories by all participants (mean rating 9.5 out of 10). Conclusions: Data from this case series of traumatized women provide preliminary evidence for the effectiveness of this novel brief intervention in reducing intrusive memories of trauma occurring several years ago and in improving functioning and reducing core symptom burden. This study will inform a randomized controlled trial of this novel intervention, which may have considerable implications for large-scale clinical management of traumatized populations.
Psychological distress and tumor cell β2-adrenergic receptor levels in patients with surgically resected non-small cell lung cancer
(2026-05-04) Hardardottir, Hronn; Aspelund, Thor; Valdimarsdottir, Bryndis; Asmundsson, Jurate; Petursdottir, Vigdis; Fall, Katja; Broström, Erika; Valdimarsdottir, Heiddis; Fang, Fang; Magnusson, Magnus K.; Gudjonsson, Thorarinn; Gudbjartsson, Tomas; Sloan, Erica K.; Lutgendorf, Susan K.; Janson, Christer; Valdimarsdottir, Unnur A.; Department of Psychology
From Organizational Resilience Capability to Firm Performance : A Time-Lagged Investigation
(2026-03-08) Chang, Yi Ying; Durst, Susanne; Hughes, Mathew; Kraus, Sascha; Clauss, Thomas; Chang, Che Yuan; Department of Business and Economics
An organizational resilience capability is essential for firms to adapt in an ever-changing world characterized by diverse crises and adversities. However, the mechanisms and contingencies needed to harness and channel organizational resilience capability remain uncertain. This article argues that this resilience capability, proactively developed in calmer times, only becomes apparent in a crisis, but its effectiveness relies on additional organizational capabilities around innovation and human resources. Using data from a sample of large Taiwanese firms collected in two waves during and after a crisis, we show how incremental and radical innovative capabilities mediate the relationship between a proactively developed organizational resilience capability and firm performance. Furthermore, we demonstrate the role of strategic human resource management practices in fostering and regulating this relationship and the functioning of innovative capabilities. Based on these findings, we provide implications for theory and practice.
Informed Trading Through the COVID-19 Pandemic : Evidence from the Bitcoin Market
(2026-01-10) Mavropoulos, Timotheos; Ersan, Oguz; Demir, Ender; Department of Business and Economics
We investigate informed trading in the Bitcoin market throughout the COVID-19 pandemic. Compared to the pre-pandemic period, we find that informed trading is significantly higher in the affective first stage of the pandemic, before reverting to its pre-COVID-19 level during the later stage of the pandemic. Furthermore, information asymmetry tends to increase in daily COVID-19-related news: confirmed cases and deaths. Our findings are robust to alternative parameters and model specifications. The main implication for traders is that they should be extra cautious in timing their trading decisions during such events, as these tend to encourage informed trading.
Soft Tissue Radiodensity Asymmetry as Clinical Indicator for Diabetes and Hypertension in Aging
(2026-01-01) Recenti, Marco; Ponsiglione, Alfonso M.; Ricciardi, Carlo; Russo, Michela; Edmunds, Kyle J.; Amato, Francesco; Gislason, Magnus K.; Carraro, Ugo; Chang, Milan; Gargiulo, Paolo; Department of Engineering
Objective: Chronic conditions like diabetes mellitus (DM) and hypertension (HTN) significantly impair physical functioning in older adults, leading to a reduced quality of life and increased risk for disability. This study evaluates the utility of soft tissue radiodensity asymmetry, derived from mid-thigh computed tomography (CT) imaging, as a biomarker for DM and HTN. Method: Using data from the AGES-Reykjavik study, the Nonlinear Trimodal Regression Analysis (NTRA) method was employed to extract 11 geometrical features from fat, muscle, and connective tissue radiodensity distributions derived from cross-sectional CT images of the mid-thigh. Asymmetry indices were calculated as the absolute differences between corresponding left and right leg parameters and were analyzed for their associations with DM and HTN. Results: Statistical analyses demonstrated that DM and HTN status altered the relationship between age and radiodensity asymmetry: DM significantly influenced muscle-specific asymmetry (Δ μ musc), while HTN showed directional trends across multiple tissue types that did not survive correction for sex, BMI, and multiple comparisons. Logistic regression identified fat tissue location asymmetry as a key predictor for DM, while connective tissue asymmetry parameters were significantly associated with HTN status. Machine learning models validated these findings, with Random Forest achieving 89.3% accuracy for DM classification and 88.1% for HTN, highlighting the robustness of these asymmetry features. Conclusions: These results establish soft tissue asymmetry as a promising novel biomarker for DM and HTN, reflecting metabolic and vascular dysfunctions. Integrating such measures into clinical practice could enhance predictive models and inform targeted interventions, improving health outcomes for aging populations.
Tracking Neural Activity Underlying Postural Control Dysfunction in a VR-Induced System : Demonstration Using BioVRSea
(2026-01-01) Ozdemir, Sumeyye; Guerrini, Lorena; Gelormini, Carmine; Guntekin, Bahar; Maruotto, Ida; Pescaglia, Federica; Hassan, Mahmoud; Gargiulo, Paolo; Allouch, Sahar; Department of Engineering
Disrupted postural control (PC), a hallmark of neurological conditions such as Parkinson's disease (PD) and mild traumatic brain injury (mTBI), is associated with altered neural oscillatory dynamics measured using electroencephalography (EEG). However, few studies have employed ecologically valid paradigms to assess these dynamics. In this study, we utilized BioVRSea, a multimodal virtual reality (VR) platform combining realistic postural perturbations with real-time EEG to examine cortical responses to multisensory stimulation. We tested whether EEG time-frequency representations could differentiate pathological PC responses in PD and mTBI from normative function in matched healthy controls (HC). Motion sickness susceptibility and symptom changes were evaluated using the Motion Sickness Susceptibility Questionnaire (MSSQ) and the Motion Sickness Symptoms Scale. In HC, only the older subgroup exhibited a significant increase in low-frequency (delta-theta, ≈ 1-7 Hz) power at 50% perturbation intensity and during the post-perturbation phase (cluster-level p <0.05). Compared with matched controls, PD participants showed increased spectral power in both the delta-theta (≈ 1-7 Hz) and alpha-beta (≈ 10-30 Hz) ranges (cluster-level p <0.05), particularly at higher perturbation intensities, suggesting impaired sensorimotor ntegration. In contrast, no significant EEG differences were observed between the mTBI group and matched controls (p > 0.05). These findings demonstrate the feasibility of synchronized VR-EEG paradigms for capturing challenge-dependent neural signatures of postural control dysfunction. Further validation is warranted to determine their potential clinical utility in neurological assessment.
Highly Compact Dual-Band Four-Port Integrated Lens MIMO Antenna for 5G New Radio IoT Devices
(2026-01-01) Malik, Bilal Tariq; Khan, Shahid; Nasir, Jamal; Koziel, Slawomir; Department of Engineering
This article introduces a highly compact, dual-wideband four-port MIMO antenna with an integrated 3D-printed dielectric lens, tailored for 5G millimeter-wave (mmWave) new radio (NR) IoT applications. The antenna's gain and port isolation are significantly enhanced by placing a hemispherical dielectric lens atop the MIMO structure. The complete integrated lens MIMO antenna (ILMA) measures just 22× 22× 20 mm3. Without the lens, the peak gain is limited to 6 dBi and 4.2 dBi at 28 GHz and 38 GHz, respectively. With the lens, gain improves to 10.5 dBi at 28 GHz and 9 dBi at 38 GHz. The antenna also achieves outstanding isolation, over 25 dB at 28 GHz and 30 dB at 38 GHz, with an envelope correlation coefficient (ECC) below 0.02 and diversity gain (DG) exceeding 9.9 dB across both bands. Link budget analysis confirms reliable communication up to 220 m at 28 GHz and 112 m at 38 GHz with 30 dBm transmit power. A fabricated prototype validates simulation results, showing strong agreement in S-parameters, isolation, gain, and radiation patterns. Compared to state-of-the-art designs, the proposed antenna offers superior gain, enhanced isolation, compact size, and cost-effective fabrication, making it well-suited for mmWave 5G NR bands such as n257, n260, and n261.

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