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Evaluation of the photoresponse in wurtzite GaN photoconductive switches is presented based on kinetic Monte Carlo simulations. The focus is on electron transport physics and assessment of high frequency operation. The roles of GaN band structure, Pauli exclusion, and treatment of internal fields based on the fast multipole method are all comprehensively included. The implementation was validated through comparisons of velocity-field characteristics for GaN with computational results in the literature. Photocurrent widths of less than ∼7 ps for the 1 μm device can be expected, which translates into a 100 GHz upper bound. Photocurrent pulse compression below the laser full width at half maxima at high applied fields are predicted based on the interplay of space-charge effects and the negative differential velocity characteristics of GaN. [ABSTRACT FROM AUTHOR]

Argues for development of a code of ethics for college faculty by answering common objectives to such codes; proposing ethical theories, principles, and rules to guide the formulation of a impartial, well-crafted code; and identifying benefits, including providing guidelines for resolving moral dilemmas, of such codes. (DB)

The magnetic sensitivity of Hall-effect sensors made of InAlN/GaN and AlGaN/GaN heterostructures was measured between room temperature and 576 °C. Both devices showed decreasing voltage-scaled magnetic sensitivity at high temperatures, declining from 53 mV/V/T to 8.3 mV/V/T for the InAlN/GaN sample and from 89 mV/V/T to 8.5 mV/V/T for the AlGaN/GaN sample, corresponding to the decreasing electron mobility due to scattering effects at elevated temperatures. Alternatively, current-scaled sensitivities remained stable over the temperature range, only varying by 13.1% from the mean of 26.3 V/A/T and 10.5% from the mean of 60.2 V/A/T for the InAlN/GaN and AlGaN/GaN samples, respectively. This is due to the minimal temperature dependence of the electron sheet density on the 2-dimensional electron gas (2DEG). Both devices showed consistency in their voltage- and current-scaled sensitivity over multiple temperature cycles as well as nearly full recovery when returned to room temperature after thermal cycling. Additionally, an AlGaN/GaN sample held at 576 °C for 12 h also showed nearly full recovery at room temperature, further suggesting that GaN-based Hall-effect sensors are a good candidate for use in high temperature applications. [ABSTRACT FROM AUTHOR]

A sharp decrease to <50% in the numbers of mucus cells mm−2 of epidermis was observed in the skin of Atlantic salmon Salmo salar at the beginning of the smoltification period in 1997 and 1999. Average numbers decreased in 1997 from 662 mm−2 on 6 March to 275 mm−2 on 20 March and in 1999 from 828 mm−2 on 3 March to 388 mm2 on 24 March. A second smaller decrease was observed towards the end of smoltification in both years. [ABSTRACT FROM AUTHOR]

This article describes a wide-field time-domain fluorescence lifetime imaging (FLIM) microscope with optical sectioning. The FLIM system utilizes a wide-field time-gated optical image intensifier, with a minimum gate width of 85 ps, to achieve high temporal resolution of fluorescence decays induced by ultrashort laser pulses. Different configurations, using excitation pulses of picojoule energy at 80 MHz repetition rate and of nanojoule energy at 10 kHz, are compared. The instrument has a temporal dynamic range spanning from 100 ps to tens of µs and is shown to have a temporal discrimination better than 10 ps. When applied to laser dye samples, it has produced FLIM maps demonstrating sensitivity to variations in both chemical species and local environment, e.g., viscosity. Wide-field optical sectioning is achieved using the technique of structured illumination, which is applied to remove out-of-focus light that can result in lifetime artifacts. The sectioning strength, which may be adjusted by choosing an appropriate spatial modulation frequency, is characterized and shown to be comparable to that of a confocal microscope. Practical considerations concerned with improving the quality of sectioned fluorescence lifetime maps, including using a large bit depth camera, are discussed. [ABSTRACT FROM AUTHOR]

We report the development of a whole-field fluorescence lifetime imaging (FLIM) system with high temporal resolution based on a time-gated image intensifier. The optimized temporal gate width is <100ps, and changes in the environment of a fluorescent phantom, causing lifetime differences less than 10ps, have been imaged. The versatility of this FLIM system has been demonstrated by measuring both the temporal and spectral profiles of multiple fluorescent samples in a single acquisition. Initial fluorescence lifetime images suggest that this technique can provide a means of distinguishing between different tissue constituents. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the role of metallic stents in treating stenoses involving prosthetic arterial bypass grafts.Methods: Patients undergoing stent placement within a failing prosthetic bypass graft, during a 41-month period, were reviewed for treatment outcome and complications. The indications for stent placement in 15 patients included severe claudication (n = 3), rest pain (n = 9), and minor or major tissue loss (n = 3). Lesions were at the proximal anastomosis (n = 6), the distal anastomosis (n = 3), or within the graft (n = 6).Results: Treatment with metallic stents was successful in all patients. There was one acute stent thrombosis, successfully treated with thrombolytic therapy. Follow-up data are available for a mean duration of 12.3 months. The mean duration of primary patency was 9.4 months with 6- and 12-month primary patency rates of 51.9% and 37.0%, respectively. The mean duration of secondary patency was 12.1 months with 6- and 12-month secondary patency rates of 80.0% and 72.7%, respectively. Two patients with discontinuous runoff and preexisting gangrene required a below-knee amputation. Six patients were revised surgically after stent placement (at a mean of 10.8 months). Three late deaths occurred during follow-up.Conclusion: Given the mortality risks of surgical revision and the reduced life expectancy of this patient population, metallic stent placement represents a viable, short-term treatment option for stenoses within or at the anastomoses of prosthetic grafts. Further evaluation is warranted to compare intragraft stent placement with surgical graft revision. [ABSTRACT FROM AUTHOR]

PURPOSE: To evaluate the safety and efficacy of the recombinant tissue plasminogen activator alteplase in the clearance of poorly functioning tunneled hemodialysis catheters. METHODS: We retrospectively reviewed the outcomes of 25 patients who presented with poorly functioning hemodialysis catheters and were treated with alteplase. After confirming fluoroscopically the need for thrombolytic therapy, alteplase was administered over 2 hours as a 2.5-mg/hour/catheter lumen infusion (total 10 mg). Treatment was considered a clinical success if a flow rate of 250 mL or more per minute was established. RESULTS: Clinical success was achieved in each of 25 patients (100%). There were no thrombolytic-related complications. Catheter survival was extended 30 days in 54% of patients and 45 days in 33% of patients. CONCLUSION: Alteplase is a safe and effective means of producing clearance of blocked tunneled catheters. [ABSTRACT FROM AUTHOR]

A new flexible bis(amidine) ligand featuring two additional N-donor groups incorporates a defined [Cu I MesCu 2 I ] 2+ fragment from mesitylcopper into a triangular cluster with a reactive organometallic coordination site. Subtle changes to the reaction protocol result in the formation of an intertwined tetracuprous arrangement that adopts the shape of a Möbius strip.

COVID-19 was a novel stressor that gave rise to pandemic related anxiety and increased the risk of mental health issues, particularly in youth. It is important to understand how such events contribute to psychological distress in young people to adequately intervene in the aftermath and to plan for future similar events. Using cross-sectional data from the CoSPACE Ireland study dataset this paper reports on the predictive relationship between COVID-19 anxiety and psychological distress for Irish adolescents ( N  = 314, M  = 14.05, SD  = 2.7, 11-18 years), while controlling for other influencing factors across multiple levels of a bioecological systems approach. Covariates were age, gender, ethnicity, social economic status, Peer Support, School Support and Parent-Child Closeness. Findings indicate that COVID-19 anxiety was a significant predictor of adolescents' psychological distress. Specifically, Consequence Anxiety (worries about the indirect consequences of COVID-19) was found to be a predictor of adolescents' psychological distress rather than Disease Anxiety (worries about the COVID-19 virus itself). Individual factors (e.g., age, ethnicity, special educational needs) and microsystem factors (e.g., parent child closeness, peer support) were also found to impact on adolescents' levels of psychological distress. A significant moderation analysis revealed that greater parent-child closeness reduced the strength of the positive association between Consequence Anxiety and psychological distress. These findings suggest that strategies to alleviate adolescents' psychological distress during pandemics should focus on reducing pandemic-related anxiety, specifically Consequence Anxiety. A multisystemic approach is also recommended to reduce the negative mental health impacts of the pandemic on adolescents., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 McMahon, Gallagher, Dowling, Donnellan, Houghton, Ryan, O’Connor and Walsh.)

Submaximal functional tests of endurance are ubiquitous in clinical practice. This investigation compared cardiovascular responses, perceived exertion, and performance measures following the completion of three self-paced, 2-minute, functional tests of endurance. A pilot prospective, observational, cross-sectional design with 16 community-dwelling older participants compared heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), rating of perceived exertion (RPE), and performance measures following the completion of three randomly allocated self-paced activities. The three activities included 2 minutes of stepping in standing (2MSTD), 2 minutes of seated stepping (2MSIT), and a 2-minute walk test (2MWT). A within-subjects repeated measures ANOVA analyzed differences in change scores for cardiovascular and RPE responses. Pearson's correlations assessed associations in performance measures between the three tests. Standing stepping compared to seated stepping produced statistically higher change scores in HR, SBP, DBP, and RPE (p < .05). Further, 2MSTD revealed statistically higher SBP and RPE scores compared to 2MWT (p < .05). Large and moderate correlations were observed between number of steps completed in sitting and standing (r = 0.83, p < .01) and between standing steps and distance walked (r = 0.56, p = .02), respectively. This pilot investigation informs home care physical therapists that 2 minutes of self-paced stepping in standing produced the greatest change scores in all cardiovascular and perceived exertion responses. No significant differences were noted in HR between self-paced walking and standing stepping, and between standing and seated stepping. For patients unable to walk or step in standing, self-paced seated stepping may be a viable alternative., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Glucagon-like peptide-1 (GLP-1) analogs are approved for the treatment of obesity in adults and adolescents. Reports have emerged that the weight loss effect of these medications may be related to changes in food preferences and ingestive behaviors following the treatment. Understanding the mechanisms which impact ingestive behavior could expand opportunities to develop more refined and personalized treatment options for obesity., Methods: Recent studies investigating the relationship between GLP-1 analogs and ingestive behaviors were retrieved from PubMed using the search terms: "obesity," "food preference," "taste," "ingestive behavior," "weight loss medication," "anti-obesity medication," "GLP-1 analog," "tirzepatide," "liraglutide," "semaglutide." Measurement tools were studied to compare variables used to assess food intake behavior. The main outcomes from each study were analyzed to evaluate the current standing and future directions of appetitive, ingestive, and consummatory behaviors and their association with GLP-1 analogs., Results: Thus far, studies have primarily explored the weight loss phase and report decreased short-term appetite and food intake upon treatment. However, research during the weight maintenance phase and objective measurements of food intake are notably sparse. Additionally, verbal reports have been primarily used to examine food intake, which can be susceptible to subjectivity., Conclusions: Elucidating the relationship between GLP-1 analogs and ingestive behavior could reveal additional parameters which contribute to their anti-obesity effects. To better understand these mechanisms, it is imperative to consider objective measurements of food intake in future studies. Several measurement tools have been adapted to measure variables of food behavior in humans, and each must be carefully considered with their strengths and limitations to develop optimal investigations., (© 2024. The Author(s).)

Joint luxations commonly occur in animals secondary to traumatic injury. Because of the unique hind-limb anatomy of macropods, surgical stabilization of orthopedic injuries is considered challenging, and reports of successful management are limited. A 4-yr-old male neutered red kangaroo ( Osphranter rufus ) presented with a dorsolateral luxation of the left tibiotarsal joint. Surgical reduction and tarsal arthrodesis were performed. Although the full range of motion of the tarsal joint was limited, this kangaroo was still able to ambulate normally at slow speeds following surgery and recovery. The aim of this report was to describe the surgical and postoperative management of a tibiotarsal luxation in a kangaroo. There were significant postoperative complications in this kangaroo, and antibiotic regional limb perfusion was used to treat wound and implant infection.

Introduction: Education in interprofessional collaboration is vital to expand healthcare access, especially in areas of higher disparity. To address this need, interprofessional faculty collaborators incorporated undergraduate and graduate health profession students into teams at an annual Remote Area Medical event in rural Appalachia between 2017 and 2020., Purpose: This article evaluates the impact of an interprofessional student teams model on both patient care experience and students' interprofessional collaboration attitudes and behaviors., Methods: Student volunteers completed pre- and post-event surveys containing questions about demographics, open-ended questions, and questions from two instruments: the Student Perceptions of Interprofessional Clinical Education-Revised Instrument, Version 2 (SPICE-R2) and the Interprofessional Collaborative Competency Attainment Scale-Revised (ICCAS-R). Quantitative data were analyzed statistically; qualitative data thematically. Tally forms collected patient care interventions that were compared to regional health disparities. Two years of survey data and four years of intervention data were analyzed., Results: There was an increase ( p < 0.001) in the post-event survey SPICE-R2 factors (teamwork, healthcare outcomes, and roles and responsibilities) in 2020 but not in 2019. ICCAS-R mean post-event composite scores increased ( p < 0.05) in both 2019 and 2020. Qualitative coding of open-ended responses revealed interprofessional competency themes and provided event feedback. Over 5,900 health-disparity-focused interventions were completed between 2017 and 2020., Implications: Students participating in interprofessional teams demonstrate changes in attitudes towards the interprofessional approach to care, an improved ability to collaborate interprofessionally, and a positive impact on patient care interventions. The findings allow educators to understand how experiential interprofessional education influences students' interprofessional attitudes and beliefs while benefitting patient care., Competing Interests: Cover Page Footnote No competing financial or editorial interests were reported by the authors of this paper., (Copyright © 2023 Emily K. Flores, KariLynn Dowling, Caroline Abercrombie MD, and Rick L. Wallace.)