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COVID-19 travel restrictions have significantly affected airline markets. A behavioural analysis is presented of 1 million customers of a major airline company over 3 years, using clickstream data, combined with COVID-19 Government Response Tracker (OxCGRT) data. The main results are that pre-pandemic, the variations in traffic volumes were seasonal and there was a consistent ratio of search (76%), buy (5%) and e-service (19%) activities across the year. The start of the pandemic caused a sharp drop in website traffic, which minimised at 1/3 of normal levels and then gradually increased so that post-covid volumes are now 20% higher, which reflects pent-up demand and consumer confidence. At the start of the pandemic, e-service increased sharply and then dropped to below pre-pandemic levels. The proportion of buyers decreased significantly at the start of the pandemic and then returned to just below pre-pandemic levels. The proportion of searchers remained high throughout the pandemic. Comparing post-pandemic with pre-pandemic, the proportion of searchers remains higher, buyers has dropped, and e-service remains the same. These results show the importance of distinguishing between different types of online activity, defined by three broad phases in the customer lifecycle: search, buy and e-service, which can only be achieved by using raw, clickstream data. Typically, web server analytics software employ aggregate data and it is much more difficult to uncover nuanced changes that are apparent at the granular level of individual clickstream data. The contribution of the research is to demonstrate a novel analytical methodology that exploits detailed clickstream data to characterize the dynamic changes in customer behaviour, which gives important insights into how online markets change in response to exogenous shocks by enabling key event analysis. Using the approaches outlined in this paper, airlines and e-commerce companies can anticipate, measure behavioural changes and be pro-active in their strategic responses to significant external events in the competitive environment that are likely to affect customer behaviour.

Bibliometric analyses of the scientific literature have grown increasingly popular in the past few decades. However, patent bibliometric studies - evaluation of technological literature, have not yet been applied in neurosurgery.To perform a pilot patent bibliometric analysis of the top 100 most cited patents in cranial neurosurgery.The Lens was used to query multiple databases, to select the top 100 cranial neurosurgical patents based upon forward patent citations. These were organized into 9 categories based on technological descriptors and were evaluated based on the earliest priority date, year issued, and expiration status, among others.The top 100 most cited patents included technology underlying 3D navigation (n=31), pharmacology and implants (n=20), vascular occlusion (n=5), craniotomy closure (n=9), focal lesioning and tissue resection (n=8), brain and systemic cooling (n=5), neuroendoscopy (n=8), neuromonitoring and stimulation (6), and technologies improving surgeon performance (n=8). 96 patents were filed in the United States, 72 were expired, 19 are still active, and 9 were listed as inactive. The highest number of patents were applied for from the mid-1990s to the mid-2000s. Demonstrated trends showed no meaningful correlation between patent rank and earliest priority date (linear trendline y=0.7107x-1367.5; RPatent bibliometrics allow evaluation of neurosurgical advancements from the past and enable subsequent development of cutting-edge technology in the future. The described method is a reproducible and reliable technique for evaluating our field's patent literature.

There is a scarcity of long-term groundwater hydrographs from sub-Saharan Africa to investigate groundwater sustainability, processes and controls. This paper presents an analysis of 21 hydrographs from semi-arid South Africa. Hydrographs from 1980 to 2000 were converted to standardised groundwater level indices and rationalised into four types (C1–C4) using hierarchical cluster analysis. Mean hydrographs for each type were cross-correlated with standardised precipitation and streamflow indices. Relationships with the El Niño–Southern Oscillation (ENSO) were also investigated. The four hydrograph types show a transition of autocorrelation over increasing timescales and increasingly subdued responses to rainfall. Type C1 strongly relates to rainfall, responding in most years, whereas C4 notably responds to only a single extreme event in 2000 and has limited relationship with rainfall. Types C2, C3 and C4 have stronger statistical relationships with standardised streamflow than standardised rainfall. C3 and C4 changes are significantly (p

The authors have withdrawn their manuscript because they can no longer stand by the behavioral data set and corresponding manuscript as submitted to bioRxiv. A colleague downloaded the data and noted seven instances where pairs of values were duplicated across trials for different pairs of stimuli (data set with duplicated values highlighted is available as supplementary data). While omitting these values from the data set does not qualitatively change the conclusions presented, we have no means to validate the remaining data and therefore feel the best course of action is to treat the whole dataset as invalid. Consequently, analyses and conclusions based wholly or partly on behavioral data are invalid as well. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author.

Background Electronic health records (EHRs) are a significant contributor to physicians’ low satisfaction, reduced engagement and increased burnout. Yet the majority of evidence around EHR and physician harms is based on self-reported screen time, which may both over- and underreport actual exposure. Aims The purpose of this study was to examine how objective EHR use correlates with physician well-being and to develop preliminary recommendations for well-being-based EHR interventions. Method Prior to the onset of COVID-19, psychiatry residents and attending physicians working in an out-patient clinic at an academic medical centre provided consent for access to EHR-usage logs and completed a well-being assessment made up of three scales: the Maslach Burnout Inventory, the Urecht Work Engagement Scale and the Professional Quality of Life Measure. Survey responses and objective EHR data were analysed with descriptive statistics. Results Responses were obtained from 20 psychiatry residents (total eligible residents n = 27; 74% participation) and 16 clinical faculty members (total eligible faculty n = 24; 67% participation) with an overall response rate of 71% (total eligible residents and faculty n = 51 and total residents and faculty who completed survey n = 36). Moderate correlations for multiple well-being domains emerged in analysis for all participants, especially around the time spent per note and patient visits closed the same day. Conclusions EHR-usage logs represent an objective tool in the evaluation and enhancement of physician well-being. Results from our pilot study suggest that metrics for note writing efficiency and closing patient visits the same day are associated with physician well-being. These metrics will be important to study in ongoing efforts involving well-being-based EHR interventions.

This article considers the requirement in a number of Australian investment treaties that a host state, following the referral of a dispute to arbitration before the International Centre for the Settlement of Investment Disputes, provide written consent to arbitration. The uncertainty around the practical operation of such provisions is problematic. It remains to be seen how International Centre for the Settlement of Investment Disputes (ICSID) tribunals will address this requirement as Australian investors become more engaged with investor-state arbitration. One would hope that a more ‘laid back’ approach to consent prevails.

Two synthetic diagnostics are implemented for the high-k scattering system in NSTX (Smith et al 2008 Rev. Sci. Instrum. 79 123501) allowing direct comparisons between the synthetic and experimentally detected frequency and wavenumber spectra of electron-scale turbulence fluctuations. Synthetic diagnostics are formulated in real-space and in wavenumber space, and are deployed in realistic electron-scale simulations carried out with the GYRO code (Candy and Waltz 2003 J. Comput. Phys. 186 545). A highly unstable electron temperature gradient (ETG) mode regime in a modest-β NSTX NBI-heated H-mode discharge is chosen for the analysis. Mapping the measured wavenumbers to field aligned coordinates shows that the high-k system is sensitive to fluctuations that are closer to the spectral peak in the density fluctuation wavenumber spectrum (streamers) than originally predicted. The analyses of synthetic spectra show that the frequency response of the detected fluctuations is dominated by Doppler shift and is insensitive to the turbulence drive. The shape of the high-k density fluctuation wavenumber spectrum is sensitive to the ETG turbulence drive conditions, and can be reproduced in a sensitivity scan of the most pertinent turbulent drive terms in the simulation.

An extensive validation effort performed for a modest-beta NSTX NBI-heated H-mode discharge predicts that electron thermal transport can be entirely explained by electron-scale turbulence fluctuations driven by the electron temperature gradient mode (ETG), both in conditions of strong and weak ETG turbulence drive. Thermal power-balance estimates computed by TRANSP as well as the shape of the high-k density fluctuation wavenumber spectrum and the fluctuation level ratio between strongly driven and weakly driven ETG-turbulence conditions can be matched by nonlinear gyrokinetic simulations and a synthetic diagnostic for high-k scattering. Linear gyrokinetic simulations suggest that the ion-scale instability in the weak ETG condition is close to the critical threshold for the kinetic ballooning mode instability, and nonlinear ion-scale gyrokinetic simulations show that turbulence might be in a state reminiscent of a Dimits' shift regime, opening speculation on the role that ion-scale turbulence might play for the weak ETG condition. A simulation that matched all experimental constraints is chosen to project high-k turbulence spectra in NSTX-U, revealing that the new high-k system [R. Barchfeld et al., Rev. Sci. Instrum. 89, 10C114 (2018)] should be sensitive to density fluctuations from radially elongated streamer structures. Two schemes are designed to characterize the radial and poloidal wavenumber dependence of the density fluctuation wavenumber power spectrum around the streamer peak, suggesting future high-k fluctuation measurements could be sensitive to an asymmetry in the kr spectrum introduced due to the presence of strong background flow shear.

SPARC is designed to be a high-field, medium-size tokamak aimed at achieving net energy gain with ion cyclotron range-of-frequencies (ICRF) as its primary auxiliary heating mechanism. Empirical predictions with conservative physics indicate that SPARC baseline plasmas would reach$Q\approx 11$, which is well above its mission objective of$Q>2$. To build confidence that SPARC will be successful, physics-based integrated modelling has also been performed. The TRANSP code coupled with the theory-based trapped gyro-Landau fluid (TGLF) turbulence model and EPED predictions for pedestal stability find that$Q\approx 9$is attainable in standard H-mode operation and confirms$Q > 2$operation is feasible even with adverse assumptions. In this analysis, ion cyclotron waves are simulated with the full wave TORIC code and alpha heating is modelled with the Monte–Carlo fast ion NUBEAM module. Detailed analysis of expected turbulence regimes with linear and nonlinear CGYRO simulations is also presented, demonstrating that profile predictions with the TGLF reduced model are in reasonable agreement.

Background:Chronic ankle instability (CAI) is linked to mechanical and functional insufficiencies. Joint mobilization is purported to be effective at treating these deficits.Purpose:To examine the effect of different treatment durations of a grade IV anterior-to-posterior ankle joint mobilization on weightbearing dorsiflexion range of motion (WB-DFROM), posterior talar glide (PG), and dynamic postural control in individuals with CAI.Study Design:Controlled laboratory study.Methods:A total of 48 female athletes (mean age, 22.8 ± 4.8 years) with unilateral CAI participated in this study. Participants were randomly assigned to 1 of 3 treatment conditions: 30 seconds, 60 seconds, and 120 seconds. Treatment was provided to the injured limb on 3 separate occasions 48 hours apart and consisted of a Maitland grade IV anterior-to-posterior talar joint mobilization based on the participant’s initial group assignment. WB-DFROM; PG; and the anterior (ANT), posteromedial (PM), and posterolateral (PL) reach directions of the Star Excursion Balance Test were measured bilaterally before and after each treatment. The uninjured limb acted as a control. Data were analyzed using 2-way mixed-model analyses of variance, and effect sizes were calculated through use of Hedges g.Results:Significant differences were detected after all treatment sessions for all outcome measures ( P ≤ .001) and between treatment groups after sessions 1, 2, and 3 for all outcome measures ( P ≤ .001). Effect sizes were very large or huge for all treatment groups for WB-DFROM, PG, and ANT reach direction. Substantial variation was found in effect sizes for PM and PL measures.Conclusion:Accessory mobilization is an effective treatment to induce acute changes in ankle motion and dynamic postural control in patients with CAI, with longer treatment durations conferring greater improvements.Clinical Relevance:This study adds clarity to the use of joint mobilization treatments and will add to the current clinical practice strategy for patients with CAI.

BACKGROUND: A golf bag filled with a set of clubs provides a substantial load. When carried over distance this can increase the demands placed upon the golfer, leading to discomfort, fatigue and injuries. This study aimed to compare the metabolic demands of 2 methods of golf bag carriage. METHODS: A total of 16 healthy male recreational golfers participated in the study. Participants were given an initial familiarization session in which their self-selected walking speed was determined. This was utilized as the treadmill speed for all subsequent trials. The testing protocol consisted of 3 randomized trials of treadmill walking for 5 minutes in each of three conditions: unloaded, single-strap bag and double-strap bag. Equipment consisted of a double-strap golf bag with a standard set of clubs weighing 12.5kg. For all trials oxygen consumption (L·min-1), VO2 (mL·kg·min-1) respiratory minute volume (VE) (L·min-1), and heart rate (HR) were measured. RESULTS: Results showed that the double-strap bag required significantly less oxygen consumption (1.19±0.19 vs. 1.31±0.16 L·min-1, P

Due to the strong nonlinear dependence of plasma turbulence on drive and dissipation mechanisms, uncertainties in experimental inputs can be greatly magnified in simulations of this turbulence. Thus, careful uncertainty quantification (UQ) and its inclusion within validation metrics is an integral part of plasma turbulence validation studies. To minimize the number of simulations required for UQ, we investigate the use of the rapidly converging nonintrusive probabilistic collocation method (PCM) for efficient plasma turbulence UQ. This approach is shown to yield more realistic uncertainty estimates than simple uniform sampling methods for a practical number of nonlinear simulations. The inclusion of UQ above and near critical gradients is discussed. To demonstrate its utility, the advantages of PCM are first illustrated using a simple model of critical gradient turbulence. It is then used on simulations from a validation study of drift-wave turbulence in the CSDX linear plasma device experiment. T...

In this paper, we report the key role that toroidal rotation and the related E × B shear physics played in the very high energy confinement quality ( H98y2>1.5) of super H-mode experiments on DIII-D. Experiments show that the energy confinement quality decreases when toroidal rotation decreases due to the decreased externally controlled torque per particle. Meanwhile, the total pedestal pressure in the experiments remains very high during the rotation and confinement quality change. TGYRO transport modeling suggests the contribution from rotation in the E × B shear is responsible for the confinement quality in excess of standard H-mode ( H98y2∼1). CGYRO gyrokinetic simulations reveal the governing physics in the core plasma of super H-modes: significant up-shift of nonlinear the ITG critical gradient is observed when applying E × B shear physics in the modeling based on experimental data. The effects of other physical parameters and contribution from pedestal height, which may play minor roles in this study, are also discussed.

The turbulence and transport expected in the SPARC tokamak Primary Reference Discharge (PRD) [P. Rodriguez-Fernandez et al., J. Plasma Phys. 86, 865860503 (2020)] have been investigated with the gyrokinetic code CGYRO [J. Candy et al., J. Comput. Phys. 324, 73–93 (2016)]. Linear and nonlinear simulations that focus on ion ( k θ ρ s 1.0) turbulence were used to probe the nature of the turbulence and the resulting transport in the fusion core. It is found that in the SPARC PRD, ion temperature gradient (ITG) turbulence is expected to dominate transport over most of the profile with some potential trapped electron mode impact in the near edge. Stiff turbulence is observed over a part of the plasma core such that SPARC's ion temperature profile will likely be pinned to just above the critical gradient for ITG. The role of electromagnetic turbulence, rotation, and electron-scale turbulence was investigated to provide some insight into the physics required to accurately predict SPARC performance via gyrokinetics. Additionally, predictions of impurity peaking for potential low- and high-Z SPARC first-wall materials are probed using ion-scale simulation. The dominance of low-k turbulence in SPARC provides a potential opportunity for more tractable prediction of plasma profiles using nonlinear gyrokinetics. This work is the first step toward full gyrokinetic profile prediction of SPARC kinetic profiles and the resulting fusion power and plasma gain.

Paralytic shellfish poisoning (PSP) is precipitated by a family of toxins produced by harmful algae, which are consumed by filter-feeding and commercially popular shellfish. The toxins, including saxitoxin, neosaxitoxin, and gonyautoxins, accumulate in shellfish and cause intoxication when consumed by humans and animals. Symptoms can range from minor neurological dysfunction to respiratory distress and death. There are over 40 different chemical congeners of saxitoxin and its analogs, many of which are toxic and many of which have low toxicity or are non-toxic. This makes accurate toxicity assessment difficult and complicates decisions regarding whether or not shellfish are safe to consume. In this study, we describe a new antibody-based bioassay that is able to detect toxic congeners (saxitoxin, neosaxitoxin, and gonyautoxins) with little cross-reactivity with the low or non-toxic congeners (decarbamoylated or di-sulfated forms). The anti-saxitoxin antibody used in this assay detects saxitoxin and neosaxitoxin, the two most toxic congers equally well, but not the relatively highly toxic gonyautoxins. By incorporating an incubation step with L-cysteine, it is possible to convert a majority of the gonyautoxins present to saxitoxin and neosaxitoxin, which are readily detected. The assay is, therefore, capable of detecting the most toxic PSP congeners found in commercially relevant shellfish. The assay was validated against samples whose toxicity was determined using standard HPLC methods and yielded a strong linear agreement between the methods, with R2 values of 0.94&ndash, 0.96. As ELISAs are rapid, inexpensive, and easy-to-use, this new commercially available PSP ELISA represents an advance in technology allowing better safety management of the seafood supply and the ability to screen large numbers of samples that can occur when monitoring is increased substantially in response to toxic bloom events

We present (i) a novel, thermally stable Atomic Layer Deposition (ALD) high-k dielectric stack that, for the first time, has the potential to meet all gate stack requirements for both n- and p-channel Ge FETs, (ii) record low contact resistivity for n-Ge/metal contacts using an implant-free contact scheme with successful implementation into a single nanowire (NW) Ge nFET baseline, (iii) single NW Ge pFETs with short-channel effect (SCE) immunity down to 24 nm physical gate length, of which electrical data show excellent agreement with calibrated models and (iv) demonstration of Ge-channel vertically stacked lateral NW FETs using a 300 mm VLSI compatible platform.

It is estimated that over 134,000 American veterans identify as transgender and over 15,000 transgender people are serving in the US military today. As such, the prevalence rates of transgender individuals seeking services at Veterans Health Administration (VHA) facilities have increased and are expected to further increase in the years to come. Historically, transgender veterans have been diagnosed with posttraumatic stress disorder (PTSD) at higher rates in comparison to their cisgender veteran counterparts. This article summarizes what is known about PTSD in gender-diverse veterans and proposes a theoretical model to describe how bio-sociocultural factors in this population may interact to increase the risk of developing PTSD. This article will attempt to identify how these risk factors not only influence the development of PTSD but also impact the severity of posttraumatic symptomology. Consolidating the current academic knowledge for this marginalized population regarding the development of PTSD will also likely aid healthcare providers in making culturally appropriate treatment modifications. Finally, the authors of this article propose a theoretical model to describe how bio-sociocultural factors may interact to increase PTSD risk in gender-diverse veterans.

A systematic evaluation of gyrokinetic and gyrofluid model predictions of ion temperature gradient (ITG) stability and transport using parameters from DIII-D high confinement mode (H-mode) plasmas has been performed. The nonlinear CGYRO code is used to make the gyrokinetic predictions, and the quasilinear TGLF model for the corresponding gyrofluid predictions. The assessments are made at three radii (normalized toroidal flux ρ tor = 0.4, 0.55, and 0.7) in three different plasma scenarios with varying levels of neutral beam heating and torque. For each of the nine cases (3 radii × 3 scenarios) considered, ITG turbulence is found to be the dominant long-wavelength instability and transport mechanism. The inclusions of both transverse magnetic fluctuations and dynamic fast beam ions are stabilizing for all cases considered, with strongest effects seen at ρ or = 0.4 where the fast ion population and normalized plasma pressure β = 2μ 0 nT/B 2 are highest. The further inclusion of parallel magnetic fluctuations does not have a meaningful impact on the ITG turbulence in these scenarios, but does destabilize (in combination with fast ions) new high-frequency instabilities at ρ tor = 0.4 in the high power scenarios. In each case the linear and nonlinear ITG critical gradients are predicted to be lower than the measured ITG scale lengths and their associated uncertainties. Inclusion of equilibrium flow shear in the transport predictions generally leads to an upshift in effective critical gradient rather than a qualitative change in the predicted stiffness, with stronger responses typically seen in the gyrokinetic predictions than in the gyrofluid results. However, in most cases these upshifted gradients still remain below the measured values and their uncertainties. Although the predicted critical gradients are below the measured gradients, both models predicted flux-matching gradients consistent with measured values in six of the nine cases considered, with no clear systematic over- or underprediction. Thus, while the experimental ion temperature profiles do not appear to be closely pinned to the ITG critical gradient, both gyrokinetic and gyrofluid models are able to accurately match the measured gradients reasonably well in most cases.

Excellent confinement has been routinely observed in DIII-D (J. L. Luxon, Nucl. Fusion 2002) high β p discharges, which are characterized by a strong large-radius internal transport barrier (ITB) in almost all kinetic channels. Typically, the ion thermal transport is neoclassical with conventional long-wavelength turbulence instabilities suppressed by α stabilization, while the mechanism for the anomalous electron thermal transport remains unclear [Garofalo et al., Nucl. Fusion 55(12), 123025 (2015)]. A new gyrokinetic analysis shows that while the large values of α in the ITB can stabilize all local electrostatic drift wave (ES-DW) instabilities as well as the kinetic ballooning mode, a new slab-like microtearing mode (MTM) with its eigenfunction mainly peaking on the high field slide is destabilized. This destabilization is shown to be more likely to happen in discharges with high safety factors. Nonlinear gyrokinetic simulations demonstrate that this MTM branch can reproduce the experimentally inferred electron thermal flux in the ITB region and, therefore, provide convincing evidence that the electron temperature profile in the ITB is regulated by the MTM. Extrapolations to the future scenarios, like ITER high β p plasmas, show that the dominant instability is likely to come back to ES-DW due to the lower density gradient and collisionality. However, even in this regime, some unusual features associated with MTMs predicted for DIII-D parameters, such as the high-field-side peaking and slab nature, may remain for the reactor ES-DW.

The thermal and fast-ion transport properties of DIII-D steady-state hybrid discharges with normalized beta β N ≳ 3 are studied at low injected torque and an increased electron to ion temperature ratio T e/T i. Linear stability analysis performed with the TGLF turbulent code indicates that a high-k mode is usually dominant at smaller radii, whereas a low-k mode is usually dominant at larger radii in these plasmas. A reduction in the net injected torque from 8.6 to 4.3 N-m leads to reduced E × B shear and hence, an enhanced turbulence that was observed on the Doppler backscattering diagnostic and was also computed with TGLF. As T e/T i in the core was increased from 0.57 to 0.66 by adding electron cyclotron current drive (ECCD) to these plasmas, higher levels of transport are observed with increased high-k modes indicated by TGLF. The fast-ion transport level varied over an order of magnitude in these discharges depending on whether Alfvén eigenmodes, fishbones, or no instabilities were observed. Hybrid plasmas with fishbones have decreased fast-ion transport, compared to plasmas with Alfvén eigenmodes, since they are resonant with a smaller portion of phase space and their resonance is farther from the wall. This reduction in fast-ion transport with ECCD mitigates the increase in turbulent transport, resulting in higher performance than expected during strong electron heating. Similarly, the lowest fast-ion transport was observed in the low torque plasma, which also led to better than expected performance at this torque value. The thermal and fast-ion transport changes observed as the torque/rotation and T e/T i are varied indicate possible methods for transferring this scenario to a reactor.

The Wilcoxon-Mann-Witney test is extended to account for a second independent factor. The new test statistic's probability mass function and normal approximation are derived. Critical-values for balanced, unbalanced, and large sample designs are given. The immediate extension of this method to a wide range of non-parametric tests is explained.

Over the last decade, plasma turbulence simulations based on gyrokinetic theory have reached an amazing degree of physical comprehensiveness and realism. In contrast to early gyrokinetic studies, w...

We report the first demonstration of InAs FinFETs with fin width $\textrm {W}_{{\mathrm{fin}}}$ in the range 25–35 nm, formed by inductively coupled plasma etching. The channel comprises defect-free, lattice-matched InAs with fin height $\textrm {H}_{{\mathrm{fin}}}=20$ nm controlled by the use of an etch stop layer incorporated into the device heterostructure. For a gate length $\textrm {L}_{{{\textrm {g}}}}=1~\mu \text{m}$ , peak transconductance $\textrm {g}_{{{\textrm {m},{\mathrm{ peak}}}}}=1430~\mu \text{S}/\mu \text{m}$ is measured at $\textrm {V}_{{\textrm {d}}}=0.5$ V demonstrating that electron transport in InAs fins can match planar devices.

We report on the first realization of InAs n-channel gate-all-around nanowire MOSFETs on 300 mm Si substrates using a fully very large-scale integration (VLSI)-compatible flow. Scaling of the equivalent oxide thickness EOT in conjunction with high- $\kappa $ dielectric engineering improves the device performance; with an optimized gate stack having an EOT of 1.0 nm, the sub-threshold swing ${S}$ is 76.8 mV/dec., and the peak transconductance ${g} _{\mathrm{ m}}$ is 1.65 mS/ ${\mu }\text{m}$ , at ${V} _{\mathrm{ ds}}$ of 0.5 V, for a gate-all-around nanowire MOSFET having a gate length ${L} _{\mathrm{ g}}$ of 90 nm, a nanowire height ${H} _{\mathrm{ NW}}$ of 25 nm, and a nanowire width ${W} _{\mathrm{ NW}}$ of 20 nm, resulting in ${Q}~\equiv ~{g} _{\mathrm{ m}}/{S} \,\, = \,\, 21.5$ , a record for InAs on silicon. Furthermore, we report a source/drain resistance ${R} _{\mathrm{ sd}}$ of 160– $200~\Omega \cdot {\mu }\text{m}$ , amongst the lowest values reported for III-V MOSFETs. Our VLSI-compatible process provides high device yield, which enables statistically reliable extraction of electron transport parameters, such as unidirectional thermal velocity ${v} _{\mathrm{ tx}}$ of 3– $4\times 10^{7}$ cm/s and back-scattering coefficient ${r} _{\mathrm{ c}}$ as a function of gate length.

Laser blow-off injections of aluminum and tungsten have been performed on the DIII-D tokamak to investigate the variation of impurity transport in a set of dedicated ion and electron heating scans with a fixed value of the external torque. The particle transport is quantified via the Bayesian inference method, which, constrained by a combination of a charge exchange recombination spectroscopy, soft x-ray measurements, and vacuum ultraviolet spectroscopy provides a detailed uncertainty quantification of transport coefficients. Contrasting discharge phases with a dominant electron and ion heating reveal a threefold drop in the impurity confinement time and order of magnitude increase in midradius impurity diffusion, when additional electron heating is applied. Furthermore, the calculated stationary aluminum density profiles reverse from peaked in electron heated to hollow in the ion heated case, following a similar trend to electron and carbon density. Comparable values of a core diffusion have been observed for W and Al ions, while differences in the propagation dynamics of these impurities are attributed to pedestal and edge transport. Modeling of the core transport with non-linear gyrokinetics code CGYRO [J. Candy and E. Belly, J. Comput. Phys. 324, 73 (2016)], significantly underpredicts the magnitude of the variation in Al transport. Diffusion increases three-times steeper with additional electron heat flux, and 10-times lower diffusion is observed in ion heated case than predicted by the modeling. The CGYRO model quantitatively matches the increase in the Al diffusion when approaching the linear threshold for the transition from the ion temperature gradient to trapped electron mode.

'The Science of Basketball' is the only book to examine the scientific principles underpinning preparation and performance in basketball, applied to both individual and team contexts. Drawing on the very latest scientific evidence, and including contributions from leading international coaches and scientists involved in the sport, the book explores every aspect of physical and mental preparation and performance.

Al x In 1− x As y Sb 1− y quaternary alloys lattice-matched to InAs were successfully grown by molecular beam epitaxy (MBE) for use as buffer layers for substrate isolation in InAs channel devices. The use of In-containing quaternary buffer layers with 5% In was found to dramatically improve the heterointerface between the buffer and a surface InAs channel layer. The composition of these alloys and the extent of lattice matching were accurately determined by double crystal X-ray measurements. A simple model was used to estimate the variation of critical thickness with lattice mismatch for AlInAsSb epitaxially grown on an InAs substrate. Layers with high Al content and low As mole fraction were grown by modulated MBE technique which was found to significantly improve the surface morphology and the composition control of the alloys. In contrast, quaternary alloys with low Al content were grown by conventional MBE and had an rms roughness of less than 0.2 nm.

Frequency (100 ${\rm Hz}\le f \le 1$ MHz) and temperature ( $- 50 \le T \le 20^{\circ }\text{C}$ ) characteristics of low interface state density $D_{\rm {it}}$ high- $\kappa $ gate-stacks on n-InAs have been investigated. Capacitance–voltage ( $C$ – $V$ ) curves exhibit typical accumulation/depletion/inversion behavior with midgap $D_{\rm {it}}$ of $2\times 10^{11}$ and $4\times 10^{11}$ cm $^{-2}$ eV $^{-1}$ at −50 °C and 20 °C, respectively. Asymmetry of low-frequency s $C$ – $V$ curves and $C$ – $T$ dependence for negative voltage showing a sharp transition of $\cong -20$ dB/decade between low- and high-frequency behavior indicate surface inversion. An inversion carrier activation energy and an InAs hole lifetime of 0.32 eV and 2 ns have been extracted, respectively. Surface channel nMOSFETs with gate length $L_{g} =$ 1 $\mu \text{m}$ , channel thickness = 10 nm, and equivalent oxide thickness (EOT) $1 \le {\rm EOT} \le 1.6$ nm have been fabricated. For ${\rm EOT} = 1$ nm, a subthreshold swing $S = 65$ mV/decade, transconductance $g_{m} =1.6$ mS/ $\mu \text{m}$ , and ON-current $I_{{\mathrm{{\scriptscriptstyle ON}}}} =$ 426 $\mu \text{A}/\mu \text{m}$ at an OFF-current $I_{{\mathrm{{\scriptscriptstyle OFF}}}} =100$ nA/ $\mu \text{m}$ (supply voltage $V_{\rm {dd}} =$ 0.5 V) have been measured. Peak electron field-effect mobilities of 6000–7000 cm $^{2}$ /Vs at sheet electron densities of 2– $3\times 10^{12}$ cm $^{-2}$ were obtained for EOT as small as 1 nm.

The integration of III-V semiconductors on silicon (Si) substrate has been an active field of research for more than 30 years. Various approaches have been investigated, including growth of buffer layers to accommodate the lattice mismatch between the Si substrate and the III-V layer, Si- or Ge-on-insulator, epitaxial transfer methods, epitaxial lateral overgrowth, aspect-ratio-trapping techniques, and interfacial misfit array formation. However, manufacturing standards have not been met and significant levels of remaining defectivity, high cost, and complex integration schemes have hampered large scale commercial impact. Here we report on low cost, relaxed, atomically smooth, and surface undulation free lattice mismatched III-V epitaxial films grown in wide-fields of micrometer size on 300 mm Si(100) and (111) substrates. The crystallographic quality of the epitaxial film beyond a few atomic layers from the Si substrate is accomplished by formation of an interfacial misfit array. This development may enable future platforms of integrated low-power logic, power amplifiers, voltage controllers, and optoelectronics components.

A new extensive validation study performed for a modest-beta National Spherical Torus eXperiment (NSTX) neutral beam injection-heated H-mode discharge predicts that electron thermal transport can be entirely explained by short-wavelength electron-scale turbulence fluctuations driven by the electron temperature gradient mode (ETG), both in conditions of strong and weak ETG turbulence drive. Quantitative comparisons between high-k fluctuation measurements (Smith et al 2008 Rev. Sci. Instrum. 79 123501) and simulations are performed via a novel synthetic high-k diagnostic. Computationally intensive electron-scale simulations featuring an unusually large domain (L r, L θ) ∼ (20, 20)ρ s are shown to be required for accurate deployment of the synthetic diagnostic. Ion thermal transport is shown to be close to neoclassical levels, consistent with stable ion-scale turbulence simulations conducted with the GYRO code (Candy and Waltz 2003 J. Comput. Phys. 186 545). Electron-scale GYRO simulations are shown to match the thermal power-balance estimates from TRANSP. The frequency spectra characteristics of electron-scale turbulence (spectral peak and width) can be consistently reproduced by the synthetic spectra, but these reveal not to be a critical constraint on the simulation model. The shape of the high-k wavenumber spectrum and the fluctuation level ratio between the strong and weak ETG conditions can also be simultaneously matched by electron-scale simulations within sensitivity scans about the experimental profile values, and result to be great discriminators of the turbulence models analyzed. Together, electron thermal power comparisons and quantitative agreement of electron-scale turbulence spectra give strong evidence supporting electron-scale ETG fluctuations as the main mechanism driving anomalous electron thermal transport in the two outer-core conditions of the modest-beta NSTX H-mode analyzed.

The L-H transition power threshold (PLH) is found to have a significant dependence on q95, at ne ∼ 3.2 × 1019 m−3 on DIII-D. Comprehensive 2D turbulence and flow measurements in the plasma edge reveal the co-existence of two frequency bands of broadband modes across the L-H transition with higher flow shear at higher q95, which can help explain the linear decrease in PLH as q95 is increased from 3.5 to 4.9. Density fluctuation measurements by beam emission spectroscopy at higher q95 show that the lower frequency band ( 20 kHz) propagates in the electron diamagnetic direction (identified as an electron mode). The turbulence amplitude at the plasma edge is higher at higher q95, implying a higher drive for a Reynolds stress driven zonal flow. At lower density, ne ∼ 1.5 × 1019 m−3, there is little dependence of PLH on q95. Linear CGYRO kinetic simulation has shown a switch from one mode to two modes at higher q95 at ne ∼ 3.2 × 1019 m−3 compared to lower q95. The ion temperature profile has been shown to strongly impact the dual mode characteristics with the increasing growth rate of the ion mode at a higher edge Ti gradient. The observations suggest that it may be possible to reduce the required input power to trigger the L-H transition for ITER if both the ion and electron modes are similarly driven in the plasma edge.The L-H transition power threshold (PLH) is found to have a significant dependence on q95, at ne ∼ 3.2 × 1019 m−3 on DIII-D. Comprehensive 2D turbulence and flow measurements in the plasma edge reveal the co-existence of two frequency bands of broadband modes across the L-H transition with higher flow shear at higher q95, which can help explain the linear decrease in PLH as q95 is increased from 3.5 to 4.9. Density fluctuation measurements by beam emission spectroscopy at higher q95 show that the lower frequency band ( 20 kHz) propagates in the electron diamagnetic direction (identified as an electron mode). The turbulence amplitude at the plasma edge is higher at higher q95, implying a higher drive for a Reynolds stress driven zonal flow. At lower density, ne ∼ 1.5 × 1019 m−3, there is little dependence of PLH on q95. Linear CGYRO kinetic simulation ...

Direct measurements of deuterium main-ion toroidal rotation spanning the linear ohmic to saturated ohmic confinement (LOC-SOC) regime and with additional electron cyclotron heating (ECH) are presented and compared with the more commonly measured impurity (carbon) ion rotation in DIII-D. Main ions carry the bulk of the plasma toroidal momentum, and hence, the shape of the main-ion rotation is more relevant to the study of angular momentum transport in tokamaks. Both in the LOC regime and with ECH, the main-ion toroidal rotation frequency is flat across the profile from the sawtooth region to the plasma separatrix. However, the impurity rotation profile possesses a rotation gradient, with the rotation frequency being lower near the plasma edge, implying a momentum pinch or negative residual stress inferred from the impurity rotation that differs from the main-ion rotation. In the SOC regime, both the main-ion and impurity rotation profiles develop a deeply hollow feature near the midradius while maintaining the offset in the edge rotation, both implying a positive core residual stress. In the radial region where the rotation gradient changes most dramatically, turbulence measurements show that density fluctuations near the trapped electron mode (TEM) scale are higher when the rotation profile is flat and drop significantly when the plasma density is raised and the rotation profile hollows, consistent with instabilities damped by collisions. Linear initial value gyrokinetic simulations with GYRO indicate that the transition from LOC-SOC in DIII-D occurs as TEMs are replaced by ion temperature gradient (ITG) driven modes from the outer radii inwards as the plasma collisionality increases, Zeff decreases, and the power flow through the ion channel progressively increases due to the electron-ion energy exchange. Gyrofluid modeling with trap gyro-Landau fluid (TGLF) successfully reproduces the plasma profiles at key times in the discharge and in time dependent simulations with predictive TRANSP. TGLF indicates that in the LOC and SOC regimes as well as with ECH, subdominant modes are present and that the plasma is not in a pure TEM or ITG binary state, but rather a more subtle mixed state. Predictions of the main-ion rotation profiles are performed with global nonlinear gyrokinetic simulations using GTS and reveal that the flat rotation is due to oscillatory variation of the turbulent residual stress across the profile, whereas the deeply hollow rotation profile is due to a larger-scale, dipole-like stress profile. In these cases, the predicted and observed main-ion rotation profile is consistent with the balance of turbulent residual stress and momentum diffusion.Direct measurements of deuterium main-ion toroidal rotation spanning the linear ohmic to saturated ohmic confinement (LOC-SOC) regime and with additional electron cyclotron heating (ECH) are presented and compared with the more commonly measured impurity (carbon) ion rotation in DIII-D. Main ions carry the bulk of the plasma toroidal momentum, and hence, the shape of the main-ion rotation is more relevant to the study of angular momentum transport in tokamaks. Both in the LOC regime and with ECH, the main-ion toroidal rotation frequency is flat across the profile from the sawtooth region to the plasma separatrix. However, the impurity rotation profile possesses a rotation gradient, with the rotation frequency being lower near the plasma edge, implying a momentum pinch or negative residual stress inferred from the impurity rotation that differs from the main-ion rotation. In the SOC regime, both the main-ion and impurity rotation profiles develop a deeply hollow feature near the midradius while maintaining...