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Wired for Risk? TRDM, Self-Control, and Peer Deviance in Cybercrime
No full textUsing data from a survey of full-time employees at a large private university (n = 872), this study examines the relationship between thoughtfully reflective decision-making (TRDM) and cybercrime and the moderating roles of self-control and deviant peer associations. Results show that TRDM, self-control, and peer associations are each significantly associated with projected cybercrime in the expected directions. Furthermore, interaction analyses reveal that, while self-control does not moderate the TRDM-cybercrime link, peer deviance does: TRDM's crime-protective effect weakens and becomes nonsignificant at higher than average levels of peer involvement in cybercrime. These findings highlight the importance of peer context in shaping the influence of reflective decision-making on cyber offending.</p
Quantum magnetic J-oscillators
No full textZero-field nuclear magnetic resonance (NMR) offers magnet-free access to nuclear spin-spin (scalar J) couplings, which define an intrinsic, molecule-specific frequency scale. However, the transient nature of zero-field NMR signals constrain spectral resolution and frequency stability. Here we introduce quantum J-oscillators that exploit J-couplings in molecules to produce phase-coherent continuous oscillations. Operated in zero magnetic field and driven by digital feedback, they generate sub-hertz to a few tens of hertz frequencies. In a proof-of-principle experiment on [15N]-acetonitrile, the oscillator achieves a 340 μHz linewidth over 3600 s, more than two orders of magnitude narrower than in conventional zero-field NMR. This methodology may facilitate precision measurements of J-coupling constants and enables discrimination of molecules whose zero-field NMR spectra are otherwise difficult to resolve. In addition, the combination of strongly coupled spin systems and programmable feedback turns J-oscillators into a compact tabletop platform for exploring nonlinear spin dynamics, including chaos and dynamical phase transitions. By uniting high-resolution spectroscopy and controllable quantum dynamics in a single, magnet-free setup, J-oscillators open new opportunities for applications where ultraprecise frequency references or molecular fingerprints are required
Size Effects on Uniaxial Compression and Tension in Recycled Aggregate Concrete Fabricated Using Conventional and Equivalent Mortar Volume Techniques
No full textThe equivalent mortar volume (EMV) method, praised for being cost-effective and efficient in improving recycled aggregate concrete (RAC) with minimal natural aggregates, is nevertheless complex regarding the internal structural impacts on uniaxial mechanical properties and size effects. This study rigorously investigates these size effects on RAC’s uniaxial tensile and compressive behaviors, fabricated via conventional and EMV methodologies, through extensive experimental and numerical analyses. Two-dimensional random polygonal aggregate models and discrete element mesomodels with heterogeneous properties were initially developed. After calibration, the impacts of the water-to-cement ratio, recycled aggregate content, and fabrication methods on compressive and tensile strengths, elastic modulus, and peak strains were thoroughly evaluated. Ultimately, size reduction coefficients for tensile and compressive strengths are proposed for practical application. Key findings include the following: (1) The EMV method significantly augments RAC’s elastic modulus and compressive strength, with a lesser effect on tensile strength. (2) Compared to conventional RAC with the same water-to-cement ratio, RAC produced using the EMV method exhibits delayed compressive damage and less severe damage overall, while tensile damage remains unchanged. Both types show similar failure patterns and crack distributions. (3) The size effect on compressive strength in the EMV method-cast-RAC aligns with that of natural aggregate concrete (NAC) with a similar water-to-cement ratio, exhibiting greater sensitivity than conventional RAC. In contrast, the tensile strength size effect is more akin to conventional RAC and less pronounced than NAC. (4) For RAC fabricated using the EMV method, size reduction coefficients of 0.70 for compressive strength and 0.77 for tensile strength are recommended for sizes ranging from 50 mm to 400 mm
Cardiovascular Risk Biomarkers Moderate the Associations Between Different Sleep Stage Durations and Global Cognition in Older Black Adults
No full textPrevalence of Cerebral Microbleeds and Association With Vascular Risk Factors in a Hispanic and Latino American Cohort
No full textThe purpose of this study was to estimate the prevalence and number of cerebral microbleeds (CMBs) in a Hispanic and Latino cohort from various self-identified backgrounds and test associations with age, vascular risk factors, APOE (apolipoprotein E), and cognitive function.
The 3T brain magnetic resonance imaging exams were obtained on SOL-INCA-MRI (Study of Latinos-Investigation of Neurocognitive Aging-MRI) magnetic resonance imaging study participants, a community-based study. CMB number was counted and categorized as: (1) any CMB, (2) lobar only, (3) deep only, (4) mixed, (5) deep+mixed, and (6) lobar+mixed. We examined whether prevalence of CMBs varied by age, sex, education, Hispanic background, cardiovascular risk factors (hypertension, diabetes, Framingham Risk Score), APOE genotype, and cognition.
A total of 2455 participants were included who were 63.0±8.4 years of age, 67.9% women, and 62.2% high school education or higher. CMBs prevalence was 11.7% (8.3% lobar only, 2.0% deep only, 1.4% mixed locations). After adjusting for age, sex, and education, a high Framingham Risk Score was associated with the presence of CMBs of all types, except lobar only. Prevalent stroke/transient ischemic attack was associated with higher likelihood of deep-only CMBs. For participants with cognitive impairment, the adjusted prevalence of mixed CMBs (2.2% versus 1.1%,
=0.023) and deep-only+mixed CMBs (5.2% versus 3.1%,
=0.010) was significantly higher compared with cognitively normal. Cognitive impairment was significantly associated with higher total CMB count (rate ratio, 1.46 [95% CI, 1.14-1.87];
=0.003). No significant associations were found between diabetes, APOE4, and any CMB type.
High vascular risk scores, self-reported history of stroke/transient ischemic attack, and cognitive status were associated with a higher likelihood of CMBs, especially in deep regions
Estimating the epidemic peak in an infection-age-structured SIR model
No full textWe investigate a susceptitble-infectious-recovered (SIR) epidemic model in which the infectious class is structured by the age of infection. We first establish the final size equation of the epidemic and prove that it admits a unique solution. We then derive two-sided estimates for the epidemic peak and provide lower and upper bounds for the peak time, which behave predictably for large population sizes. In the particular case of constant transmission and recovery rates, these bounds coincide, yielding an explicit expression for the peak time. Our results extend and refine previous findings for the classical SIR model, providing new analytical insights into epidemic dynamics with infection-age structure, which are relevant for mathematical modeling and applied studies in epidemiology
Building excellence in simulation programs: Experiences and examples from ASPIRE Award recipients and panellists
No full textExcellence in educational practice is recognised by the ASPIRE Award program at AMEE. The focus of this paper draws on exemplars from the ASPIRE-to-Excellence Award for Simulation to illustrate how excellence is built in simulation programs. Our focus is on institutional programs that support entry-level and practising clinicians in developing and maintaining clinical knowledge and skills, thereby impacting patient safety and quality of care. We briefly outline the history of the award and then describe the elements and criteria for the award. We position the award alongside the many standards of practice, professional guidelines, quality frameworks, accreditation and certification documents available to the healthcare simulation community. Selected sub-criteria are illustrated making explicit what excellence looks like. We then shift focus to characterise panellists' credentials and share their reflections on the process of reviewing applications, followed by reflections from awardees on the benefits of the award and their experience of preparing the application. We draw on all these reflections to offer tips for preparing an application. Institutional program review in comparison to established international standards for excellence can facilitate improvements to simulation programs, even if it does not progress to a formal submission or award
Endogenous Versus Exogenous Candida Endophthalmitis: Clinical Features, Risk Factors, Treatment Modalities, and Visual Outcomes
No full textTo characterize the clinical features, risk factors, treatment modalities, and visual outcomes of culture-proven Candida endophthalmitis at a tertiary referral center.Retrospective, single-center, consecutive case series.Forty-six eyes of 46 patients with culture-proven Candida endophthalmitis treated between October 1, 2014, and October 1, 2025.Diagnosis was confirmed by positive intraocular (aqueous or vitreous sample) cultures. Clinical records were reviewed for demographics, comorbidities, risk factors, infection type, treatment course, and visual outcomes.Candida species distribution, clinical presentation, associated risk factors, treatment modalities, complications, and visual acuity (VA) at last follow-up.C. albicans was the most common isolate (32/46, 69.6%), predominating in endogenous cases (92.3%), while non-albicans Candida species were frequent in exogenous infections (C. tropicalis 5/20, 25.0%; C. parapsilosis 4/20, 20.0%; C. glabrata 3/20, 5.0%; P<0.001). Endogenous cases were associated with recent hospitalization (8/26, 30.8%), intravenous drug use (IVDU, 8/26, 30.8%), and malignancy (6/26, 23.1%), whereas exogenous infections were related to recent ocular procedure or surgery (16/20, 80.0%) or recent external ocular infection (4/20, 20.0%). Pars plana vitrectomy (PPV) was performed in 25/26 (96.1%) of endogenous and 13/20 (65.0%) of exogenous cases (P=0.014). Among intravitreally injected eyes, voriconazole was the most commonly used antifungal agent (35/38, 92.1%). Among systemically treated eyes, fluconazole was the most frequently used antifungal agent (19/37, 51.4%). The most common complication was retinal detachment in both groups (9/46, 19.6%). At last follow-up, VA was significantly better in endogenous than exogenous infection (0.5 LogMAR [∼20/63] vs. 2.3 LogMAR [∼20/3990]; P=0.005). Enucleation/evisceration was performed in 1/26 (3.8%) of endogenous cases and 3/20 (15.0%) of exogenous cases.Candida endophthalmitis demonstrates distinct clinical profiles and visual outcomes based on infection source. Endogenous cases, most commonly due to C. albicans, are associated with systemic comorbidities and show comparatively better visual outcomes. Exogenous cases, frequently caused by non-albicans Candida species, are more refractory despite prompt antifungal therapy, vitrectomy, and anterior segment surgeries, often resulting poor visual outcomes
