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The neurocognitive health effects of repetitive head impacts have been examined in many sports. However, characterizations of head impacts for sliding-sport athletes are lacking. To describe head impact kinematics and injury epidemiology in elite athletes during the 2021–2022 Bobsleigh World Cup season. Cross-sectional study. On-track training and competitions during the Bobsleigh World Cup season. Twelve elite bobsleigh athletes (3 pilots [1 female], 9 push athletes [5 females]; age = 30 ± 5 years; female height and weight = 173 ± 8 cm and 75 ± 5 kg, respectively; male height and weight = 183 ± 5 cm and 101 ± 5 kg, respectively). Athletes wore an accelerometer-enabled mouthguard to quantify 6-degrees-of-freedom head impact kinematics. Isometric absolute and relative neck strength, number of head acceleration events (HAEs), workload (J), peak linear velocity (m·s−1), peak angular velocity (rad·s−1), peak linear acceleration (g), and peak angular acceleration (rad·s−2) were derived from mouthguard manufacturer algorithms. Linear mixed-effect models tested the effects of sex (male versus female), setting (training versus competition), and position (pilot versus push athlete) on the kinematic variables. A total of 1900 HAEs were recorded over 48 training and 53 competition days. No differences were found between the number of HAEs per run per athlete by sex (incidence rate ratio [IRR] = 0.82, P =.741), setting (IRR = 0.94, P =.325), or position (IRR = 1.64, P =.463). No sex differences were observed for workload (mean ± SD: males = 3.3 ± 2.2 J, females = 3.1 ± 1.9 J; P =.646), peak linear velocity (males = 1.1 ± 0.3 m·s−1, females = 1.1 ± 0.3 m·s−1; P =.706), peak angular velocity (males = 4.2 ± 2.1 rad·s−1, females = 4.7 ± 2.5 rad·s−1; P =.220), peak linear acceleration (male = 12.4 ± 3.9g, females = 11.9 ± 3.5g; P =.772), or peak angular acceleration (males = 610 ± 353 rad·s−2, females = 680 ± 423 rad·s−2; P =.547). Also, no effects of setting or position on any kinematic variables were seen. Male athletes had greater peak neck strength than female athletes for all neck movements, aside from right-side flexion (P =.085), but no sex differences were noted in relative neck strength. We provide a foundational understanding of the repetitive HAEs that occur in bobsleigh athletes. Future authors should determine the effects of repetitive head impacts on neurocognitive function and mental health. [ABSTRACT FROM AUTHOR]

Several cardiovascular disease (CVD) risk factors (e.g., hypertension, poor glycemic control) can affect and be affected by autonomic nervous system (ANS) activity. Since excess adiposity can influence CVD development through its effect on hypertension and diabetes mellitus, it is important to determine how adiposity and altered ANS activity are related. The present study employed structural equation modeling to investigate the relation between adiposity and ANS activity both directly and indirectly through biological variables typically associated with glycemic impairment and cardiac stress in older adults. Utilizing the Atherosclerosis Risk in Communities (ARIC) dataset, 1,145 non-smoking adults (74±4.8 yrs, 62.8% female) free from known CVD, hypertension, and diabetes and not currently taking beta-blockers were evaluated for fasting blood glucose (FBG), insulin, and HbA1c concentrations, waist circumference (WC), blood pressure (BP), and markers of ANS activity. WC was recorded just above the iliac crest and was used to reflect central adiposity. Resting 2-minute electrocardiograph recordings, pulse wave velocity, and ankle-brachial index data were used to assess the root mean square of successive differences in RR intervals (RMSSD) and the pre-ejection period (PEP), markers of parasympathetic and sympathetic activity, respectively. FBG, insulin, and HbA1c inferred a latent variable termed glycemic impairment (GI), whereas heart rate and diastolic BP inferred a latent variable termed cardiac stress (CS). The structural equation model fit was acceptable [root mean square error of approximation = 0.050 (90% CI =.036,.066), comparative fit index =.970, Tucker Lewis Index = 0.929], with adiposity having both significant direct (β = 0.208, p = 0.018) and indirect (β = -.217, p =.041) effects on PEP through GI. Adiposity displayed no significant direct effect on RMSSD. CS displayed a significant pathway (β = -0.524, p = 0.035) on RMSSD, but the indirect effect of WC on RMSSD through CS did not reach statistical significance (β = -0.094, p = 0.137). These results suggest that adiposity's relation to ANS activity is multifaceted, as increased central adiposity had opposing direct and indirect effects on markers of sympathetic activity in this population of older adults. [ABSTRACT FROM AUTHOR]

Protein modification by ubiquitin fold modifier 1 (UFM1), termed ufmylation, regulates various physiological and pathological processes. Among emerging UFM1 targets, UFM1 binding protein 1 (UFBP1) is the first identified ufmylation substrate. Recent clinical and animal studies have demonstrated the pivotal roles of UFBP1 in development, hematopoiesis, intestinal homeostasis, chondrogenesis, and neuronal development, which has been linked to its function in maintaining endoplasmic reticulum (ER) homeostasis. However, the importance of UFBP1 ufmylation in these cellular and physiological processes has yet to be determined. It has been proposed that ufmylation of lysine 268 (267 in humans) in UFBP1 plays a critical role in mediating the effects of the ufmylation pathway. In this study, we for the first time probe the pathophysiological significance of UFBP1 ufmylation in vivo by creating and characterizing a mouse UFBP1 knockin (KI) model in which the lysine 268 of UFBP1, the amino acid accepting UFM1, was mutated to arginine. Our results showed that the K268R mutation reduced the total ufmylated proteins without altering the expression levels of individual ufmylation enzymes in mouse embryonic fibroblasts. The K268R mutation did not alter ER stress–stimuli–induced ER stress signaling or cell death in mouse embryonic fibroblasts. The homozygous KI mice were viable and morphologically indistinguishable from their littermate wild–type controls up to one year of age. Serial echocardiography revealed no cardiac functional impairment of the homozygous KI mice. Furthermore, the homozygous KI mice exhibited the same susceptibility to dextran sulfate sodium (DSS) –induced colitis as wild-type mice. Taken together, these results suggest that UFBP1 K268 is dispensable for ER stress response, embryonic development, cardiac homeostasis under physiological conditions, and intestinal homeostasis under pathological conditions. Our studies call for future investigations to understand the biological function of UFBP1 ufmylation and offer a new mouse model to determine the roles of UFBP1 ufmylation in different tissues under stress conditions. [ABSTRACT FROM AUTHOR]

The effects of acute exercise on the cortisol awakening response (CAR), characterized by the rapid increase in cortisol concentrations within the 30–45 min following sleep offset has yet to be fully elucidated. Thus, our study investigated the effects of late-evening acute exercise on the CAR the following morning. We hypothesized that exercise would have a significant effect on the CAR the following morning. Twelve participants (mean (SD): age = 23 (4) years; mass = 76.8 (8.7) kg; height = 175.6 (5.0) cm; V ˙ O2max = 48.9 (7.5) ml.kg−1.min−1) reported to the laboratory in the evening (1800 h) on two occasions and were randomly assigned to either exercise for one hour (70–75% of maximal power output) or rest condition. Blood and saliva samples were assayed for cortisol. Mixed-effects models determined the effect of exercise on the cortisol response post-waking in both blood and saliva. Participants demonstrated an average exercise-induced increase in circulating cortisol of 477.3%, with actual mean (SD) heart rate relative to maximum of 87.04% (6.14%). Model results demonstrated a negative effect for exercise condition when modeling the serum and salivary cortisol responses to awakening via a quadratic growth model (serum, βCondition = − 42.26 [95% CI − 64.52 to − 20.01], p < 0.001; saliva, βCondition = − 11.55 [95% CI − 15.52 to − 7.57], p < 0.001). These results suggest that cortisol concentrations in saliva and blood are significantly lower the morning following a prior evening exercise session. Therefore, the CAR may serve as a useful biomarker to monitor responses to exercise training, although the underlying mechanism for these decreases in the CAR should be investigated further. [ABSTRACT FROM AUTHOR]

Semi-insulating GaN films with controlled dopant profiles have significant potential to improve the performance of high-power electronics. Beryllium doped GaN (GaN:Be) films previously demonstrated a semi-insulating nature, but the Be-dopant profiles in these films exhibited Be surface segregation and accumulation, which would lead to undesired leakage current paths in devices and deterioration of breakdown voltage. Improved growth kinetics of metal modulated epitaxy at low growth temperatures are applied in the study of GaN:Be films to achieve selectively controlled and abrupt step-doped Be profiles. The GaN:Be films were found to be semi-insulating via Hall effect measurements at elevated temperatures of 495 K. The films were shown to effectively electrically compensate surface contaminants at regrowth interfaces. Surface contaminants (O, Si, and C) typically result in unintentional n-type doping at the GaN on GaN regrowth interface. In order to demonstrate the utility of Be doping, GaN:Mg p-type films are grown atop GaN:Be buffer, AlN buffer, and control samples without any insulating buffer on GaN:Fe templates. Remarkably, the p-type films grown atop control samples up to 400 nm thick are compensated from surface contaminants, whereas the films grown atop AlN and GaN:Be insulating layers effectively electrically neutralize the surface contaminants and result in high hole concentrations of 2.3 and 2.5 × 1019 cm−3, respectively. The use of GaN:Be instead of AlN buffers eliminates the need to deconvolve the effects of the AlN/GaN 2D sheet charges and defects from lattice mismatch, removes lateral conduction paths, and reduces inherently high static vertical electric fields that detract from power device performance. [ABSTRACT FROM AUTHOR]

Coppus, TA, Anderson, T, Hurley, E, Gill, DL, and Brown, PK. The practical utility of objective training load indices in Division I college soccer players. J Strength Cond Res 36(4): 1026-1030, 2022-The aim of this study was to investigate the association of subjective session rating of perceived exertion with objective training load measures and explored data reduction approaches for 26 commonly measured objective load metrics. One National Collegiate Athletic Association Division I male soccer team (N = 28) provided 26 objective measures via a global positioning system and heart rate monitor system and self-report rating of perceived exertion measures for all team activities through the 12-week 2019 fall championship season. The singular associations between session rating of perceived exertion (sRPE) and objective load metrics were assessed via repeated-measures correlation and collectively assessed via elastic net regression. Principal components analysis was then used to reduce the dimensionality of objective load variables. Level of significance for the study was [alpha] <= 0.05. The training load variable had the highest correlation with sRPE (r = 0.85) among the 26 metrics. Twenty variables were retained in the elastic-net regression and demonstrated an R 2 of 0.76. The principal components analysis demonstrated a 4-component solution. The components were qualitatively described as "moderate- or high-intensity external load," "low-intensity load," "high-intensity internal load," and "average internal load" and accounted for 46, 32, 16, and 6% of the variance, respectively. The sRPE metric had strong correlations with multiple objective measures, demonstrating its utility for practitioners monitoring training load in collegiate soccer with limited resources. Furthermore, the consolidation of 26 metrics into 4 components while retaining data variability allows coaches to focus on a small number of metrics and employ a data-driven approach to training. /p> [ABSTRACT FROM AUTHOR]

• Deep-ultraviolet (DUV) laser source for laboratory-based photoemission microscopy. • Intense, narrowband, and tunable output from 192 nm to 210 nm (6.5 eV to 5.9 eV). • Characterize space charge effects at 80 MHz repetition rate in PEEM measurements. • High DUV flux allows high resolution studies of wide bandgap semiconductors. Photoemission electron microscopy (PEEM) is a unique and powerful tool for studying the electronic properties of materials and surfaces. However, it requires intense and well-controlled light sources with photon energies ranging from the UV to soft X-rays for achieving high spatial resolution and image contrast. Traditionally, many PEEMs were installed at synchrotron light sources to access intense and tunable soft X-rays. More recently, the maturation of solid-state lasers has opened a new avenue for laboratory-based PEEMs using laser-based UV light at lower photon energies. Here, we report on the characteristics of a laser-based UV light source that was recently integrated with a PEEM instrument. The system consists of a high repetition rate, tunable wavelength laser coupled to a harmonics generation module, which generates deep-UV radiation from 192 nm to 210 nm. We comment on the spectral characteristics and overall laser system stability, as well as on the effects of space charge within the PEEM microscope at high UV laser fluxes. Further, we show an example of imaging on gallium nitride, where the higher UV photon energy and flux of the laser provides considerably improved image quality, compared to a conventional light source. These results demonstrate the capabilities of laser-based UV light sources for advancing laboratory-based PEEMs. [ABSTRACT FROM AUTHOR]

Two American collegiate football linemen completed physical activity surveys, anthropometric assessments, dietary recalls, and blood draws across a 20-month period during which Player A continued training professionally in football while Player B transitioned out of the sport after his final collegiate season. Few changes were observed for Player A, whereas notable changes in physical activity, body mass, and endocrine factors associated with metabolic regulation were noted in Player B. Considerable alterations in physical activity and biomarkers occurred in the immediate transition out of competitive football, suggesting the possibility of long-term health consequences in the absence of future positive lifestyle behavioral changes. Alternatively, the adoption or maintenance of health behaviors could reverse risks. With a greater emphasis on lifespan wellness, this level 2 exploratory case series illustrates a key opportunity for athletic trainers to monitor athletes' cardiometabolic risks over an extended period and implement transitional care strategies to promote postcompetitive health. [ABSTRACT FROM AUTHOR]

GaN is a favorable martial for future efficient high voltage power switches. GaN has not dominated the power electronics market due to immature substrate, homoepitaxial growth, and immature processing technology. Understanding the impact of the substrate and homoepitaxial growth on the device performance is crucial for boosting the performance of GaN. In this work, we studied vertical GaN PiN diodes that were fabricated on non-homogenous Hydride Vapor Phase Epitaxy (HVPE) substrates from two different vendors. We show that defects which stemmed from growth techniques manifest themselves as leakage hubs. Different non-homogenous substrates showed different distribution of those defects spatially with the lesser quality substrates clustering those defects in clusters that causes pre-mature breakdown. Energetically these defects are mostly mid-gap around 1.8Ev with light emission spans from 450nm to 700nm. Photon emission spectrometry and hyperspectral electroluminescence were used to locate these defects spatially and energetically. [ABSTRACT FROM AUTHOR]

Context: Although fatigue has been implicated in anterior cruciate ligament (ACL) injury, few researchers have examined the timing of injury across a competitive sport season or within a competitive session to gain insight into the potential effects of fatigue on the incidence of ACL injury. Objective: To identify the time segments across a competitive season or within an individual competition associated with the greatest ACL injury incidence. Design: Descriptive epidemiology study. Methods: Data from the National Collegiate Athletic Association Injury Surveillance Program for 2004-2005 through 2015-2016 for basketball, lacrosse, and soccer were analyzed. Incidence rate ratios (IRRs) compared ACL injury rates by sport, sex, season segment, and competition period. Poisson regression was used to examine the associations between each of these categories and the incidence of ACL injury as well as interaction effects. Results: During the early regular season, the incidence rate was elevated relative to the preseason (IRR = 1.86; 95% confidence interval [CI] = 1.27, 2.74), middle regular season (IRR = 1.48; 95% CI = 1.01, 2.15), late regular season (IRR = 1.56; 95% CI=1.08, 2.27), and postseason (IRR=2.20; 95% CI = 1.06, 4.56). A sport-by-season interaction indicated this effect was largely attributable to a higher incidence in the early season among lacrosse athletes. An interaction between season segment and competition period (P = .02) revealed a greater injury incidence before halftime in the early regular season (IRR = 0.38, 95% CI = 0.19, 0.76), but a greater incidence after halftime in the late regular season (IRR = 2.40, 95% CI = 1.15, 5.02). Fewer noncontact injuries occurred in soccer than in basketball or lacrosse. Conclusions: The ACL injury incidence was higher in the early part of the regular season, particularly among lacrosse athletes. Although the injury incidences before and after halftime were similar, further analyses of player time and time of injury within each half are necessary. Coaches and practitioners should be cognizant of the elevated injury incidence during the early season among lacrosse athletes. Future authors should consider more specific analyses to further elucidate the potential role of fatigue development in exacerbating the incidence of ACL injury in collegiate athletes both within games and across the season. [ABSTRACT FROM AUTHOR]

The cortisol awakening response (CAR) is often assessed in the saliva and considered to be representative of serum cortisol. However, free cortisol is rapidly converted into cortisone as it passes from the serum into the saliva. Because of this enzymatic conversion, the salivary cortisone awakening response (EAR) may be more closely related to serum cortisol dynamics than the salivary CAR. Therefore, the purpose of this study was to measure the EAR and CAR in saliva and compare it to the serum CAR. Male participants (n = 12) had an intravenous catheter placed for serial serum sampling and completed two overnight laboratory sessions, wherein participants slept in the laboratory and saliva and serum samples were collected every 15 min after volitional awakening the following morning. Serum was assayed for total cortisol and saliva for cortisol and cortisone. The CAR and EAR was assessed in saliva and the CAR in serum via mixed-effects growth models and common awakening response indices (area under the curve [AUC] relative to the ground [AUC G ] and relative to the increase [AUC I ], and change scores [Δ]). There was a distinct rise in salivary cortisone following awakening demonstrating the presence of a discernable EAR (β Quadratic = −41.18, [95%CI = −68.90 to −13.46], p < 0.004, Conditional R2 = 0.641). Two EAR indices (AUC G : p < 0.001 and AUC I : p = 0.030) were associated with the corresponding serum CAR indices. We demonstrate for the first time a distinct cortisone awakening response. The results suggest the EAR may be more closely related to serum cortisol dynamics during the post-awakening period, and thus, may be a biomarker of interest in addition to the CAR for assessing hypothalamic-pituitary-adrenal axis functioning. • This is one of the first studies to explicity test for and demonstrate the presence of a cortisone awakening response. • The cortisone awakening response is associated with blood-based cortisol awakening response. • Researchers should consider cortisone as an alternative hormone for assessing salivary awakening responses. [ABSTRACT FROM AUTHOR]

The activation of ion implanted p-type dopants in GaN is notoriously difficult as the extremely high temperatures required to activate implanted Mg also damage the GaN crystal. In this paper, we present refinements to our novel annealing process (symmetric multicycle rapid thermal annealing) to reduce surface damage and contamination responsible for elevated leakage currents and non-ideal diode behavior. Furthermore, we apply the technique to Mg-implanted bulk GaN substrates to enable vertical power device structures, demonstrating rectifying p-i-n junctions. In addition, the technique was applied for edge termination in both p-i-n and Schottky barrier diodes, realizing floating guard ring and junction termination extension structures. The processes demonstrated here represents a key enabling step for future GaN-based power devices. [ABSTRACT FROM AUTHOR]

Purpose: Cortisol (C) and testosterone (T) are impacted significantly by prolonged endurance exercise with inverse responses. Increases in C are witnessed concurrently with decrements in T, possibly impacting recovery. This study was conducted to assess the dynamics of C and free T (fT) concentration and recovery time following an exhaustive endurance exercise session (EES).Methods: 12 endurance-trained males (X ± SD: VO2max 66.3±4.8 ml/kg/min, age 22.8 ± 3.1 years, body fat 11.0 ± 1.4 %, training 7.1 ± 3.2 years) completed a treadmill EES at ventilatory threshold (74.7 ± 4.6 % of VO2max; 96.9 ± 10.8 min). Basal blood C and fT were collected at baseline: -48, -24 h, and immediately before (0 h) the EES as well as immediately (+0 h), +24 h, +48 h, and +72 h after the EES. Blood glucose (G) was measured to confirm no undue influence on C. Statistically data were analyzed with repeated measures ANOVA (LSD post hoc).Results: C (nmol/L) increased significantly from -48 h (321 ± 59) to +0 h (701 ± 178) (p < 0.001), and displayed a baseline overshoot with +24 h (209 ± 67) being significantly lower than -48 and +0 h (p < 0.03). fT (pmol/L) decreased significantly from -48 h (161 ± 40) to +0 h (106 ± 38) (p < 0.01) and remained lower at +24 h (110 ± 33) and +48 h (129 ± 30) (p < 0.001). G remained stable throughout. A moderately negative correlation (r = -0.636, p < 0.026) was found between C and fT at +0 h.Conclusions: EES recovery may require 48 h for C and 72 h for fT to return to baseline values. Furthermore, C and fT were only correlated immediately post-exercise. Future research should perform more frequent measurements throughout time course. [ABSTRACT FROM AUTHOR]

Top-side integration of nanocrystalline diamond films in the fabrication sequence of AlGaN/GaN high electron mobility transistors is demonstrated. Reliable oxygen plasma etching of the diamond capping layer, required for a diamond-before-gate process, was implemented by using a sacrificial SiN 'dummy' gate. Hall characterization showed minimal (∼6%) reduction in sheet carrier density and commensurate increase in sheet resistance, while maintaining mobility and on-state drain current density. Off-state drain current and threshold voltage were increased, likely by fluorination of the AlGaN surface after removal of the sacrificial gate, even though a 20 nm thick Al2O3 layer was used as a SF6-plasma etch stop. Pulsed IDS and on-resistance were improved, indicating that a 10 nm SiN/500 nm NCD could offer improved AlGaN surface passivation compared to a more conventional 100 nm thick PECVD SiN film. [ABSTRACT FROM AUTHOR]

An Mg-implanted p-i-n diode was fabricated and characterized. Mg activation was achieved using the multicycle rapid thermal annealing technique with rapid heating pulses up to 1340 °C. The surface of the implanted GaN after annealing was smooth (0.94 nm RMS roughness) with growth steps evident as characterized by atomic force microscopy. The full width at half-maximum of the implanted GaN E2 Raman mode approaches that of the as-grown GaN after the annealing process, indicating that the annealing process is able to reverse most of the implantation damage. The Mg-implanted p-i-n diode exhibits rectification and a low leakage current of 0.11 μA cm−2 at a bias of −10 V. Under forward bias, light emission was observed from the p-i-n diode. The implantation and activation of Mg in a GaN-based device, demonstrated for the first time in this research, is a key enabling step for future optoelectronic and power electronic devices. Current-voltage characteristics of the Mg-implanted p-i-n diode with an inset of the device schematic. [ABSTRACT FROM AUTHOR]

A dry process for selective etching of nanocrystalline diamond thin films has been developed as an alternative to plasma etching. This process relies on subjecting masked diamond films to a controlled oxygen atmosphere at temperatures of 700–800 °C to controllably etch both vertically through the film and laterally underneath the mask. SiO 2 , SiN x , and Al 2 O 3 films constitute viable mask materials for this process, provided that the underlying diamond film is fully outgassed before mask deposition and diamond etching. As expected, etching occurred more rapidly at higher temperatures. The etch rate was higher in the lateral direction than the vertical direction, which has been attributed to accelerated etching along disordered grain boundaries and the underlying nucleation layer. Similar activation energies (136–140 kJ/mol) were obtained for both lateral and vertical etching from 700 to 800 °C. Using the dry etch process developed in this research, diamond films can be removed from exposed features and undercut masked regions at a controlled rate, as indicated by microscopy and Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Background: The ability to monitor changes in daily hydration status is critical for human health and performance. Monitoring changes in body weight (W), urine color (U), and thirst (T) was proposed as a simple, low-cost method for daily hydration monitoring [1]. However, the ability of these metrics to accurately predict 24-h hydration status is yet to be fully tested. Objective: The purpose of this study was to assess the degree to which daily monitoring of W, U, and T (i.e., the WUT model) could accurately predict 24-h hydration status. Methods: Thirty-five male and female adults (age: 23.4 ± 4.1 years, height: 173.0 ± 10.3 cm, mass: 77.2 ± 18.2 kg, body fat: 18.4 ± 8.4%) were monitored for 8 consecutive days. Assessments on each morning included a 24-h urine sample for urine osmolality (UOSM24), a first void spot urine for urine color (U), nude body weight (W), and perceived thirst (T) using a 1–9 Likert scale. On days 7 and 8, a blood sample was taken for copeptin assessment [2]. If UOSM24 was >800 mOsm•kg−1 on any day, the participants were classified as hypohydrated. Multiple research questions were explored. First, models tested the degree to which W, U, and T could predict UOSM24 (RQ1). Classification models assessed the ability to predict whether an individual was hypohydrated (UOSM24 >800 mOsm•kg−1; RQ2). Last, models tested the degree to which W, U, and T could predict concentrations of copeptin (RQ3). For each question, 4 separate modeling approaches were used: linear regression (LR), elastic net regression (EN), extreme gradient boosted random forests (XB), and a single hidden layer neural network (NN). Eighty percent of the data (RQ1/RQ2 n = 207, RQ3 n = 49) were used to train the models, while 20% of the data were held out (RQ1/RQ2 n = 51, RQ3 n = 10) for model validation. Within the training data, bootstrap samples (XB) and cross-fold validation (EN and NN) samples were used to optimize model hyperparameters. Prediction accuracy for regression analyses were assessed via R2 and root mean square error (RMSE), and for classification analyses via area under the curve of the receiver operating characteristic. Results: The results demonstrated that the NN model performed best when predicting UOSM24 (R2 = 0.532, RMSE = 228 mOsm•kg−1), but all models had relatively poor fit and large errors during validation. All classification models were moderately effective at discriminating between the binary hydration status of individuals (area under the curve of the receiver operating characteristic range: 0.661–0.696). Linear regression (Fig. 1; R2 = 0.929, RMSE = 1.49 pmol•L−1), XB (R2 = 0.834, RMSE = 3.11 pmol•L−1), EN (R2 = 0.890, RMSE = 2.13 pmol•L−1), and NN (R2 = 0.930, RMSE = 1.84 pmol•L−1) were able to predict copeptin concentrations with relatively low error. Conclusions: The WUT model accurately predicts copeptin concentrations on out of training data observations, suggesting that first morning measures of W, U, and T are effective for tracking hydration status by indirectly monitoring arginine vasopressin. More research is needed to determine potential cut-scores of predicted copeptin levels to aid practitioner decisions. [ABSTRACT FROM AUTHOR]

Current controversies manifest an inherent tension between artistic freedom and moral constraint--a tension exacerbated by our reluctance or inability to define modem art. This paper maintains that Kant and Hegel are two of the pivotal figures with which any reflections on the ground, nature, and limits of artistic freedom must begin. Both philosophers, for example, explicitly argue that artist and audience alike require a certain kind and a certain degree of freedom in order to carry out their respective projects, be they creative, cognitive, or aesthetic. While Kant's interest in art is limited mostly to its aesthetic affects, i.e., the faculty-driven feelings associated with beauty and the sublime, Hegel rejects feelings of any kind as constituting a proper subjectmatter for philosophy, and so reaffirms the classical conception of art as essentially an expression of truth. Despite these fundamental differences, the two philosophers' respective explanations of art and artistic autonomy must both be considered if we are to understand properly modem and post-historical forms of art, which for all their novelty and differences (both real and apparent) draw heavily on both the Kantian and Hegelian traditions for their justification. So, while Kant and Hegel may not supply us with direct or decisive ways to think through contemporary issues involving artistic freedom or questions concerning the moral legitimacy of art, they can help us map out the historical landscape of philosophical thought on art and artistic autonomy and thereby provide us with the prolegomena to such an effort. [ABSTRACT FROM AUTHOR]

This article presents the use of flexible carbon substrates for the growth of III-nitride nanowire light emitters. A dense packing of gallium nitride nanowires were grown on a carbon paper substrate. The nanowires grew predominantly along the a-plane direction, normal to the local surface of the carbon paper. Strong photo- and electro-luminescence was observed from InGaN quantum well light emitting diode nanowires. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

A series of redox flow batteries utilizing mixed addenda (vanadium and tungsten), phosphorus-based polyoxometalates (A-α-PV3W9O406−, B-α-PV3W9O406−, and P2V3W15O629−) were prepared and tested. Cyclic voltammetry and bulk electrolysis experiments on the Keggin compounds (A-α-PV3W9O406− and B-α-PV3W9O406−) established that the vanadium centers of these compounds could be used as the positive electrode (PVIV3WVI9O409−/PVV3WVI9O406−), and the tungsten centers could be used as the negative electrode (PVIV3WVI9O409−/PVIV3WV3WVI6O4012−) since these electrochemical processes are separated by about 1 V. The results showed that A-α-PV3W9O406− (where A indicates adjacent, corner-sharing vanadium atoms) had coulombic efficiencies (charge in divided by charge out) above 80%, while the coulombic efficiency of B-α-PV3W9O406− (where B indicates adjacent edge-sharing vanadium atoms) fluctuated between 50% and 70% during cycling. The electrochemical yield, a measurement of the actual charge or discharge observed in comparison with the theoretical charge, was between 40% and 50% for A-α-PV3W9O406−, and 31P NMR showed small amounts of PV2W10O405− and PVW11O404− formed with cycling. The electrochemical yield for B-α-PV3W9O406− decreased from 90% to around 60% due to precipitation of the compound on the electrode, but there were no decomposition products detected in the solution by 31P NMR, and infrared data on the electrode suggested that the cluster remained intact. Testing of P2V3W15O629− (Wells–Dawson structure) suggested higher charge density clusters were not as suitable as the Keggin structures for a redox flow battery due to the poor stability and inaccessibility of the highly reduced materials. [ABSTRACT FROM AUTHOR]

Soliton-like pulses with a 1984-nm center wavelength are produced from a Tm-doped mode-locked fiber laser. The linear cavity has a graphene saturable absorber mirror at one end and a fiber Bragg grating as the output coupler. The laser operates without dispersion compensation, and the repetition rate was tuned from 20 to 5 MHz by the addition of SMF-28 fiber. The dry transfer process used to place the graphene on a mirror could be extended to any optical substrate. This enables integration of graphene with optics such as an optical window coated with a graphene filter or a graphene-saturable absorber placed directly on a semiconductor laser facet. [ABSTRACT FROM AUTHOR]

The article discusses works by philosopher Martin Heidegger in light of his perspectives on aesthetics, architecture, and architectural aesthetics. The author presents an interpretation of Heidegger's works and argues that in the article "The Origin of the Work of Art," Heidegger presents a complicated view of the ontology of art and compares it to the philosophies presented in the book "Being in Time," also by Heidegger. He discusses the categorization of architecture based on physical properties as well as the object's perception and use. Buildings designed by architects Antonio Gaudi, Daniel Libeskind, and Frank Gehry are discussed.

An iron-based ionic liquid, Fe((OHCH2CH2)2NH)6(CF3SO3)3, is synthesized in a single-step complexation reaction. Infrared and Raman data suggest NH(CH2CH2OH)2primarily coordinates to Fe(iii) through alcohol groups. The compound has Tgand Tdvalues of −64 °C and 260 °C, respectively. Cyclic voltammetry reveals quasi-reversible Fe(iii)/Fe(ii) reduction waves. [ABSTRACT FROM AUTHOR]

The Na+ and [Cu(en)2(H2O)2]2+ (en = ethylenediamine) salt of a pseudosandwich-type heteropolyniobate forms upon prolonged heating of Cu(NO3)2 and hydrated Na14[(SiOH)2Si2Nb16O54] in a mixed water-en solution. The structure [a = 14.992(2) Å, b = 25.426(4) Å, c = 30.046(4) Å, orthorhombic, Pnn2, R1 = 6.04%, based on 25869 unique reflections] consists of two [Na(SiOH)2Si2Nb16O54]13- units linked by six sodium cations, and this sandwich is charge-balanced by five [Cu(en)2(H2O)2]2+ complexes, seven protons, and three additional sodium atoms (all per a sandwich-type cluster). Diffuse-reflectance UV-vis indicates that there is a λmax at 383 nm for the CuII d-d transition and the 29Si MAS NMR spectrum has two peaks at -78.2 ppm (151 Hz) and -75.5 ppm (257 Hz) for the two pairs of symmetry-equivalent internal [SiO4]4- and external [SiO3(OH)]3- tetrahedra, respectively. Unlike tungsten-based sandwich-type complexes, the [Na(SiOH)2Si2Nb16O54]13- units are linked exclusively by Na+ instead of one or more d-electron metals. [ABSTRACT FROM AUTHOR]

The free testosterone to cortisol ratio (fTC) and heart rate variability (HRV) indices have been independently proposed as objective biomarkers of physiological resilience and readiness, respectively. It is hypothesized that individuals that enter a training period with high resilience and readiness would have a greater positive response to the training. PURPOSE: Therefore, the purpose of this study was to investigate the association between fTC and HRV with fitness changes in division I male college soccer players. METHODS: Two division I teams were recruited to participate in this study. Participants completed an orthostatic HRV challenge (supine, sitting, standing) and provided blood samples prior to the 6-week Spring training period. The HRV indices of root mean square of successive differences (RMSSD) and high frequency power (autoregressive, normalized; HF) were calculated in all postural conditions. Blood samples were assayed for free testosterone and cortisol using competitive binding ELISAs. Participants completed the yo-yo intermittent recovery test (YYIR) before and after the 6-week training period and the absolute increase in distance (m) achieved during the YYIR represented the change in fitness (YYIRΔ). Separate linear regression models tested the association of fTC and all HRV indices and their interactions with YYIRΔ. All predictors were first centered and scaled and alpha level was set at p < 0.05 for all models. RESULTS: Participants (n = 21, age = 19.5±1.0 years, height = 179.0±6.4 cm, weight = 76.9±9.4 kg, body fat = 12.6±4.3 %) from the two teams did not differ in YYIRΔ (mean±SD = 438±212, p = 0.64). A significant association with YYIRΔ was observed for the interaction between fTC and HFsitting (F(3,17) = 4.31, β = 4.92,p = 0.02, R² = 0.33). No other indices or interactions were significantly associated with YYIRΔ. CONCLUSIONS: These results suggest that HRV and fTC represent potential objective pre-training biomarkers capable of identifying athletes that will be most responsive to individualized fitness and conditioning programs. Further research is necessary to confirm the utility of these specific objective biomarkers in larger cohorts and across multiple training situations. [ABSTRACT FROM AUTHOR]

PURPOSE: Animal research suggests that variations in daily dietary macronutrient distribution may impact fluid consumption. However, this has not been fully investigated in humans. Thus, the purpose of this study was to determine the impact of dietary intake on fluid intake, thirst, and urinary hydration biomarkers. METHODS: Thirty-four participants (44% female; age: 23±4 years; height: 172.9±10.3cm; body mass: 77.2±18.1kg; body fat: 18.4± 8.4%) recorded their food and fluid intake, and provided a 24h urine sample over seven consecutive days. Urinary hydration biomarkers included urine volume (UVOL), urine osmolality (UOSM), urine specific gravity (USG), and urine color (UCOL). Each morning, participants completed two subjective ratings of perceived thirst; a 9-point Likert scale, and 100mm visual analog scales comprised of six indices (thirstiness, pleasantness, dryness, taste, fullness, sickness). RESULTS: Mean weekly macronutrient percentages and total calorie intake were used in multiple regression models as predictors of average total fluid intake, thirst, and urinary hydration markers. Throughout the week, participants reported consuming, on average, 1945±429 calories (36.5±4.4% fat, 44.3±6.3% carbohydrate, 18.5±4.5% protein) and 2508±1122mL fluid per day. Mean 7-day 24h urinary hydration markers were UVOL:1724±850mL, USG :1.017±0.005, UOSM: 565±212, UCOL: 3.89±0.99. Dietary intake that was higher in percentage of fat consumed was associated with higher ratings of "fullness" on morning thirst scale sub ratings (adj R² = 0.1181, p =0.0167). Consuming a greater proportion of calories from protein was associated with increased UVOL (adj R² = 0.1370, p = 0.0340). However, protein intake was not significantly associated with fluid intake (adj R2 = 0.0569, p = 0.2516), regardless of the type of fluid consumed (p > 0.05). UOSM, USG, UCOL and the other indices of thirst were not associated with macronutrient consumption (p>0.05). CONCLUSION: These results suggest increased consumption of dietary protein intake is associated with improved hydration status based on increased 24h urine volume, with the maintenance of other urinary hydration indices. Grant or Funding Information: This study was funded by a University of North Carolina at Greensboro Office of Research Engagement New Faculty Grant. [ABSTRACT FROM AUTHOR]

In contradiction to current bonding paradigms, two terminal Au-oxo molecular complexes have been synthesized by reaction of AuCl3 with metal oxide-cluster ligands that model redox-active metal oxide surfaces. Use of K10[α2-P2W17O61]·20H2O and K2WO4 (forming the [A-PW9O34]9- ligand in situ) produces K15H2[Au(O)(OH2)P2W18O68]·25H2O (1); use of K10[P2W20O70(OH2)2]·22H2O (3) produces K7H2[Au(O)(OH2)-P2W20O70(OH2)2]·27H2O (2). Complex 1 crystallizes in orthorhombic Fddd, with a = 28.594(4) Å, b = 31 .866(4) Å, c = 38.241 (5) Å, V= 34844(7) ų, Z= 16 (final R = 0.0540), and complex 2 crystallizes in hexagonal P6(3)/mmc, with a = 16.1730(9) Å, b = 16.1730(9) Å, c = 19.7659(15) Å, V = 4477.4(5) ų, Z = 2 (final R = 0.0634). The polyanion unit in 1 is disorder-tree. Very short (~1.76 Å) Au-oxo distances are established by both X-ray and 30 K neutron diffraction studies, and the latter confirms oxo and trans aqua (H2O) ligands on Au. Seven findings clarify that Au and not W is present in the Au-oxo position in 1 and 2. Five lines of evidence are consistent with the presence of d8 Au(III) centers that are stabilized by the flanking polytungstate ligands in both 1 and 2: redox titrations, electrochemical measurements, 17 K optical spectra, Au L2 edge X-ray absorption spectroscopy, and Au-oxo bond distances. Variable-temperature magnetic susceptibility data for crystalline 1 and 2 establish that both solids are diamagnetic, and 31P and 17O NMR spectroscopy confirm that both remain diamagnetic in solution. Both complexes have been further characterized by FT-IR, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and other techniques. [ABSTRACT FROM AUTHOR]

Rates of steady oxygen-isotope exchange differ in interesting ways for two sets of structural oxygens in the [HxTa6O19](8-x)-(aq) Lindqvist ion when compared to published data on the [HxNb6O19]8-x(aq) version. Because of the lanthanide contraction, the [HxTa6O19](8-x-(aq) and [HxNb6O19](8-x-(aq) ions are virtually isostructural and differ primarily in a full core (Kr vs Xe) and the 4f14 electrons in the [HxTa6O19](8-x-(aq) ion. For both molecules, both pH-dependent and -independent pathways are evident in isotopic exchange of the 12 μ2-O(H) and 6 ηO sites. Rate parameters for ηO exchange at conditions where there is no pH dependence are, for the Ta(V) and Nb(V) versions respectively, k0298 = 2.72 × 10-5 s-1 and 9.7 × 10-6 s-1, ΔH‡ = 83.6 ± 3.2 and 89.4 kJ·mol-1, and ΔS‡ = -51.0 ± 10.6 and -42.9 J·mol-1·K-1. For the μ2-O sites, K0298 = 1.23 × 10-6 s-1, ΔH‡ = 70.3 ± 9.7 and 88.0 kJ·mol-1, and ΔS‡ = -116.1 ± 32.7 and -29.4 J·mol-1·K-1. Protonation of the 6 ηO sites is energetically unfavored relative to the 12 μ2-O bridges in both molecules, although not equally so. Experimentally, protonation labilizes both the μ2-O(H) and ηO sites to isotopic exchange in both molecules. Density-functional electronic- structure calculations indicate that proton affinities of structural oxygens in the two molecules differ with the [HxTa6O19](8-x)-(aq) anion having a smaller affinity to protonate than the [HxNb6O19]8-x(aq) ion. This difference in proton affinities is evident in the solution chemistry as pKa = 11.5 for the [HTa6O19]7-(aq) ion and pKa = 13.6 for the [HNb6O19]7-(aq) ion. Most striking is the observation that ηO sites isotopically equilibrate faster than the μ2-O sites for the [HxTa6O19](8-x)-(aq) Lindqvist ion but slower for the [HxNb6O19](8-x)-(aq) ion, indicating that predictions about site reactivities in complicated structures, such as the interface of aqueous solutions and oxide solids, should be approached with great caution. [ABSTRACT FROM AUTHOR]

Key experiments in three developing dioxygen activation and oxo transfer projects are described. First, the Pt–oxo complex, K7Na9PtIV(O)(OH2)(PW9O34)2 (KNa1) is further addressed and its first reactivity is noted (oxo transfer under Ar at ambient temperature to PPh3 forming O=PPh3 with nearly quantitative selectivity). Second, an unusually reactive catalyst for aerobic oxygenation of sulfides to sulfoxides (TBANO3 in the presence of TBA4Fe(H2O)PW11O39 in acetonitrile solvent) is reported and its stoichiometry is established to be the desired atom-efficient dioxygenase one (RSR+(1/2)O2→RS(O)R). Third, a crystalline microporous solid (metal organic framework material) capable of catalyzing air-based oxidations is described. Reaction of the bis(triesterified)hexavanadate unit terminating in two carboxylate functions, [(n-C4H9)4N]2[V6O13{(CH2O)3CNHCH2(4-C6H4COOH)}2] reacts with Co(NO3)2·6H2O and 4,4′-bipyridine to form a ladder-like microporous polymer, characterized by X-ray crystallography, that catalyzes the air-based oxidation of a representative thiol, n-PrSH, cleanly to the corresponding disulfide, PrSSPr. The esterified hexavanadate units are the catalysts, and there is no reaction in the absence of the microporous material. [Copyright &y& Elsevier]

The reaction of Fe(III) with Na+ and K+ salts of the trivacant [α-SiW9O34]10- ligand have been investigated at pH 6 and pH 1. A new dimer, [(α-SiFe3W9(OH)3O34)2(OH)3]11- (1), is synthesized by reacting Na7H3[α-SiW9O34] or K10[α-SiW9O34] with exactly 3 equiv of Fe(III) in a 0.5 M sodium acetate solution (pH 6). The structure of 1, determined by single-crystal X-ray diffraction (a = 22.454(2) Å, b = 12.387(2) Å, c = 37.421(2), β = 100.107(8)°, monodinic, C2/c, Z = 4, R1 = 5.11% based on 12739 independent reflections), consists of two [α-SiFe3W9-(OH)3O34]4- units linked by three Fe-μ-OH-Fe bonds. Reaction of K10[α-SiW9O34] with 3 equiv of Fe(III) in water (pH 1) yields [(α-Si(FeOH2)2FeW9(OH)3O34)2]8- (2). The structure of 2 was also determined by single-crystal X-ray diffraction (a = 36.903(2) Å, b = 13.9868(9) Å, c = 21.7839(13) Å, β = 122.709(1)°, monoclinic, C2/c, Z = 4, R1 = 4.57% based on 11787 independent reflections). It consists of two [α-Si(FeOH2)2FeW9(OH)3O34]4- Keggin units linked by a single edge. The terminal ligand on Fe1 in each trisubstituted Keggin unit becomes a μ2 oxo ligand bridging to a [WO6]2- moiety. The UV-vis spectra of both complexes show the characteristic oxygen-tometal-charge-transfer bands of polyoxometalates as well as an Fe(III)-centered band at 436 nm (∈ = 146 M-1 cm-1) and 456 nm (∈ = 104 M-1 cm-1) for complexes 1 and 2, respectively. Differential scanning calorimetry data show that complex 1 decomposes between 575 and 600 °C whereas no decomposition is observed for complex 2 up to temperatures of 600 °C. [ABSTRACT FROM AUTHOR]

Presents the decomposition of A-Type sandwiches. Focus on the synthesis and characterization of polyoxometalates (POM) incorporating multiple d-electron-centered units; Revelation of the general formula of the transition metal substituted POM; Determination of the 1Mn structure through single-crystal x-ray diffraction; Effectiveness of the 1Mn methyltricaprylammonium salt as catalyst of cyclohexane epoxidation.

Discusses the preparation and characterization of a coordination polymer composed of a mixed-addenda polyoxometalate bridged by aquated Cu(II) units. Selective aerobic sulfoxidation of thioethers; Spectrum screening of combinations of redox-active transition metal cations and oxidizing anions; Catalytic activity; X-ray crystallography.

Investigates the M[sub 3]O[sub 13] unit isomerization in the classical polytungstodiphosphates α- and β-P[sub 2]W[sub 18]O[sub 62][sup 6-]. Thermodynamic stabilities of the alpha; versus β isomers; Reaction of the lacunary compounds with vanadium precursor; Isomerization of the resulting lacunary compound.

Examines the structure of Wells-Dawson heteropolytungstates in multi-iron complex. Epoxidation of alkenes; Distortion of the d-electron-containing metal ions; Chemical reaction of nickel with the polypoxometalate.

Examines the reaction of the diferric sandwich-type polyoxometalate (POM) with excess aqueous copper (Cu)(II). Development of rational methods for the systematic modification of POM systems; Correlation between metal cations and POM; Determination of the catalytic oxidation of alkenes.

Activation of ion‐implanted p‐type dopants in gallium nitride has demonstrated great progress utilizing high pressures to enable novel and traditional device architectures; however, such conditions consistently exhibit anomalously enhanced diffusion up to several microns in very short periods of time for device relevant concentrations. Here, this diffusion is shown to be modulated by unintentional hydrogen content within the anneal ambient and thus controllable by inclusion of a high‐temperature hydrogen getter. Furthermore, diffusion is also shown to be greatly suppressed using co‐implanted oxygen at low concentrations while simultaneously maintaining characteristics of p‐type material in photoluminescence. Subsequently, after annealing at 1300 °C for 30 min in 3.8 kbar of nitrogen pressure, the magnesium concentration in the diffusion tail is suppressed by 28% at 1–1.5 μm in depth using a hydrogen getter alone, which reduces hydrogen uptake by 45% and fully suppressed at >1 μm in depth using co‐implantation alone and further reduced with concurrent use of a hydrogen getter. Co‐implantation alone reduces the in‐diffused magnesium dose by 60% compared to reference samples. [ABSTRACT FROM AUTHOR]

The cortisol awakening response (CAR) describes the increase in cortisol within the first 30–60 min after waking from nocturnal sleep, and is a common biomarker used within psychoneuroendocrinology, but the effect of sleep on the CAR is currently unclear. A previous study suggested that reported discrepancies may be due to other lifestyle behaviors such as physical activity; given the role of the CAR in energy regulation and preparation for the day, it is theoretically plausible that activity level would influence the CAR. However, no study has yet utilized objective monitoring of day-to-day sleep and physical activity to investigate potential effects on the CAR. This study aimed to test the hypotheses that either sleep duration or sleep quality would interact with the prior 24 h′ physical activity to predict the CAR on the following morning. Salivary samples were collected from 85 young adults (mean = 19.1 years, SD = 1.89) immediately after waking from nocturnal sleep and again 30 min after waking; two complete and consecutive days were used. Participants wore accelerometers (ActiGraph, wGT3X-BT) throughout this phase of a larger study, which provided objective measures of sleep duration, number of awakenings, and amount of physical activity. Mixed-effects models with post-hoc regions of significance decompositions tested the hypothesized interaction effects. Results demonstrated a significant interaction between prior day sleep duration and physical activity predicting the next day CAR, wherein short sleep duration and high levels of physical activity resulted in an augmented CAR. Although more sleep clearly predicted a smaller next day CAR in main effect, this study provides additional support that sleep duration effects are also moderated by prior day physical activity. Both behavioral factors should be considered when assessing the CAR and the association between the CAR other psychoneuroendocrine outcomes. • The interaction of objectively measured previous day sleep duration and physical activity predicts the CAR. • The interaction of physical activity and sleep quality, as assessed by the number of awakenings, does not predict the CAR. • Short sleep durations coupled with high levels of physical activity was related to an augmented CAR. • Future investigations of the CAR should consider the effect of physical activity when investigating sleep parameters. [ABSTRACT FROM AUTHOR]

Examines the decisive relation between truth and art. How Martin Heidegger describes truth in his book `Der Ursprung des Kunstwerkes'; Discovery made by Heidegger while attempting to trace the essence of truth to its ground; Analysis of poetic transfigurations in art and poetry.

Focuses on the philosophy of Emmanuel Levinas concerning art and morality. Definition of heterotopia; Artistic and moral order; Tragedy as disclosing heterotopic space; Levinas' critique of art; Ethical differences of a tragic and sterile life.

Abstract: An AlGaN/GaN HEMT was irradiated with 5MeV protons at a dose up to 2×1015/cm2. Photoluminescence spectra measured at 5K indicated that GaN lattice was severely damaged by collisions with high energy protons although distinct near band-edge features were still observable. An I DS–V DS measurement showed that the current level was decreased by 43% after proton irradiation, and an I GS–V GS measurement suggested that damage at the metal-contact/AlGaN interface was minimal. Transistor operation was found to be resistant to proton irradiation, which was partially attributed to a self-healing mechanism in proximity to the AlGaN/GaN interface. [Copyright &y& Elsevier]

Discusses the synthesis of a carbonate-encapsulated sandwich-type yttrium poloxymetalates. Reaction of a A-α-PW[sub 9]O[sub 34][sup 9-] with YCl[sub 3] in an aqueous Na[sub 2]CO[sub 3] solution; Production of the first dianion-encapsulated A-type sandwich polyoxometalate; X-ray structure of the complex; Sandwiching of three Y (III) ions between two A-α-PW[sub 9]O[sub 34][sup 9-] moieties.

The low thermal conductivity of β-Ga2O3 is a significant concern for maximizing the potential of this ultra-wide bandgap semiconductor as a power switching device technology. Here, we report on the use of nanocrystalline diamond (NCD) deposited via microwave plasma enhanced chemical vapor deposition (MP-CVD) as a top-side, device-level thermal management solution on a lateral β-Ga2O3 transistor. NCD was grown via MP-CVD on β-(AlxGa1−x)2O3/β-Ga2O3 heterostructures prior to the gate formation of the field-effect transistor. A reduced growth temperature of 400 °C and a SiNx barrier layer were used to protect the oxide semiconductors from etching in the MP-CVD H2 plasma environment. Raman spectroscopy showed a highly sp3-bonded NCD film was obtained at 400 °C, with grain size of about 50–100 nm imaged via atomic force microscopy. The incorporation of the NCD heat-spreading layer resulted in a β-(AlxGa1−x)2O3/β-Ga2O3 heterostructure field-effect transistor showing a decrease in the total thermal resistance at the gate by 42%. The fabrication process, including the NCD etch in the gate region, will need to be improved to minimize the impact of these processes on important device characteristics (i.e., drain current, threshold voltage, and leakage current). [ABSTRACT FROM AUTHOR]