A cavity loadlock apparatus for next-generation quantum optics experiments.

Cavity quantum electrodynamics (QED), the study of the interaction between quantized emitters and photons confined in an optical cavity, is an important tool for quantum science in computing, networking, and synthetic matter. In atomic cavity QED, this approach typically relies upon an ultrahigh vacuum chamber that hosts a cold trapped atomic ensemble and an optical cavity. Upgrading the cavity necessitates a months-long laborious process of removing external optics, venting, replacing the resonator, baking, and replacing optics, constituting a substantial bottleneck to innovation in resonator design. In this work, we demonstrate that the flexibility of optical cavities and the quick turnaround time in switching between them can be restored with the vacuum loadlock technique-reducing the cycle time to install a cavity, bake it, and transport it into the science chamber for days, achieving 3 × 10-10 Torr pressure in the science chamber. By reducing vacuum limitations, this approach is particularly powerful for labs interested in quickly exploring novel optic cavities or any other atomic physics relying on in-vacuum optics.

Impact on all-cause mortality of a case prediction and prevention intervention designed to reduce secondary care utilisation: findings from a randomised controlled trial.

BACKGROUND: Health coaching services could help to reduce emergency healthcare utilisation for patients targeted proactively by a clinical prediction model (CPM) predicting patient likelihood of future hospitalisations. Such interventions are designed to empower patients to confidently manage their own health and effectively utilise wider resources. Using CPMs to identify patients, rather than prespecified criteria, accommodates for the dynamic hospital user population and for sufficient time to provide preventative support. However, it is unclear how this care model would negatively impact survival. METHODS: Emergency Department (ED) attenders and hospital inpatients between 2015 and 2019 were automatically screened for their risk of hospitalisation within 6 months of discharge using a locally trained CPM on routine data. Those considered at risk and screened as suitable for the intervention were contacted for consent and randomised to one-to-one telephone health coaching for 4-6 months, led by registered health professionals, or routine care with no contact after randomisation. The intervention involved motivational guidance, support for self-care, health education, and coordination of social and medical services. Co-primary outcomes were emergency hospitalisation and ED attendances, which will be reported separately. Mortality at 24 months was a safety endpoint. RESULTS: Analysis among 1688 consented participants (35% invitation rate from the CPM, median age 75 years, 52% female, 1139 intervention, 549 control) suggested no significant difference in overall mortality between treatment groups (HR (95% CI): 0.82 (0.62, 1.08), pr(HR<1=0.92), but did suggest a significantly lower mortality in men aged >75 years (HR (95% CI): 0.57 (0.37, 0.84), number needed to treat=8). Excluding one site unable to adopt a CPM indicated stronger impact for this patient subgroup (HR (95% CI): 0.45 (0.26, 0.76)). CONCLUSIONS: Early mortality in men aged >75 years may be reduced by supporting individuals at risk of unplanned hospitalisation with a clear outreach, out-of-hospital nurse-led, telephone-based coaching care model.

Quantum-enabled millimetre wave to optical transduction using neutral atoms.

Early experiments with transiting circular Rydberg atoms in a superconducting resonator laid the foundations of modern cavity and circuit quantum electrodynamics1, and helped explore the defining features of quantum mechanics such as entanglement. Whereas ultracold atoms and superconducting circuits have since taken rather independent paths in the exploration of new physics, taking advantage of their complementary strengths in an integrated system enables access to fundamentally new parameter regimes and device capabilities2,3. Here we report on such a system, coupling an ensemble of cold 85Rb atoms simultaneously to an, as far as we are aware, first-of-its-kind optically accessible, three-dimensional superconducting resonator4 and a vibration-suppressed optical cavity in a cryogenic (5 K) environment. To demonstrate the capabilities of this platform, and with an eye towards quantum networking5, we leverage the strong coupling between Rydberg atoms and the superconducting resonator to implement a quantum-enabled millimetre wave (mmwave) photon to optical photon transducer6. We measured an internal conversion efficiency of 58(11)%, a conversion bandwidth of 360(20) kHz and added thermal noise of 0.6 photons, in agreement with a parameter-free theory. Extensions of this technique will allow near-unity efficiency transduction in both the mmwave and microwave regimes. More broadly, our results open a new field of hybrid mmwave/optical quantum science, with prospects for operation deep in the strong coupling regime for efficient generation of metrologically or computationally useful entangled states7 and quantum simulation/computation with strong non-local interactions8.

Two-Experiment Examination of Habitual and Manipulated Foot Placement Angles on the Kinetics, Kinematics, and Muscle Forces of the Barbell Back Squat in Male Lifters.

This two-experiment study aimed to examine the effects of different habitual foot placement angles and also the effects of manipulating the foot placement angle on the kinetics, three-dimensional kinematics and muscle forces of the squat. In experiment 1, seventy lifters completed squats at 70% of their one repetition maximum using a self-preferred placement angle. They were separated based on their habitual foot angle into three groups HIGH, MEDIUM and LOW. In experiment 2, twenty lifters performed squats using the same relative mass in four different foot placement angle conditions (0°, 21°, 42° and control). Three-dimensional kinematics were measured using an eight-camera motion analysis system, ground reaction forces (GRF) using a force platform, and muscle forces using musculoskeletal modelling techniques. In experiment 1, the impulse of the medial GRF, in the descent and ascent phases, was significantly greater in the HIGH group compared to LOW, and in experiment 2 statistically greater in the 42° compared to the 21°, 0° and control conditions. Experiment 2 showed that the control condition statistically increased quadriceps muscle forces in relation to 0°, whereas the 0° condition significantly enhanced gluteus maximus, gastrocnemius and soleus forces compared to control. In experiment 1, patellofemoral joint stress was significantly greater in the HIGH group compared to LOW, and in experiment 2, patellar and patellofemoral loading were statistically greater in the control compared to the 42°, 21°, 0° and control conditions. Owing to the greater medial GRF's, increased foot placement angles may improve physical preparedness for sprint performance and rapid changes of direction. Reducing the foot angle may attenuate the biomechanical mechanisms linked to the aetiology of knee pathologies and to promote gluteus maximus, gastrocnemius and soleus muscular development. As such, though there does not appear to be an optimal foot placement angle, the observations from this study can be utilised by both strength and conditioning and sports therapy practitioners seeking to maximise training and rehabilitative adaptations.

Optical mode conversion in coupled Fabry-Perot resonators.

Low-loss conversion among a complete and orthogonal set of optical modes is important for high-bandwidth quantum and classical communication. In this Letter, we explore tunable impedance mismatch between coupled Fabry-Perot resonators as a powerful tool for manipulation of the spatial and temporal properties of optical fields. In the single-mode regime, frequency-dependent impedance matching enables tunable finesse optical resonators. Introducing the spatial dependence of the impedance mismatch enables coherent spatial mode conversion of optical photons at near-unity efficiency. We experimentally demonstrate a NIR resonator whose finesse is tunable over a decade, and an optical mode converter with efficiency >75% for the first six Hermite-Gauss modes. We anticipate that this new perspective on coupled multimode resonators will have exciting applications in micro- and nano-photonics and computer-aided inverse design.

Rasch's Logistic Model Applied to Growth.

Rasch's logistic model for growth is explained by reviewing his analysis of piglet growth. An early formulation was given in India when Rasch visited with Rao to describe the statistic metameter as the distinguishing characteristic for determining the rate of growth. Next, several examples are given demonstrating growth with plots of growth over time using characteristic time with truncated data. The results of these growth plots and analyses are summarized given their implications and restraints for using this approach in determining rate of growth.

Loevinger on Unidimensional Tests with Reference to Guttman, Rasch, and Wright.

Loevinger's specifications for a unidimensional test are discussed. The implications are reviewed using commentary from Guttman's and Rasch's specification for specific objectivity. A large population is sampled to evaluate the implications of this approach in light of Wright's early presentation regarding data analysis. The results of this analysis show the sample follows the specifications of Loevinger and those of Rasch for a unidimensional test.

NephCure Accelerating Cures Institute: A Multidisciplinary Consortium to Improve Care for Nephrotic Syndrome.

INTRODUCTION: NephCure Accelerating Cures Institute (NACI) is a collaborative organization sponsored by NephCure Kidney International and the University of Michigan. The Institute is composed of 7 cores designed to improve treatment options and outcomes for patients with glomerular disease: Clinical Trials Network, Data Warehouse, Patient-Reported Outcomes (PRO) and Endpoints Consortium, Clinical Trials Consulting Team, Quality Initiatives, Education and Engagement, and Data Coordinating Center. METHODS: The Trials Network includes 22 community- and hospital-based nephrology practices, 14 of which are trial-only sites. Eight sites participate in the NACI Registry, and as of October 2017, 1054 patients are enrolled with diagnoses including but not limited to focal segmental glomerulosclerosis, minimal change disease, membranous nephropathy, IgA nephropathy, and childhood-onset nephrotic syndrome. By using electronic health record data extraction, robust and efficient clinical data are captured while minimizing the burden to site-based network staff. RESULTS: The Data Warehouse includes her-extracted data from registry patients, PRO development data, and data from completed observational studies and clinical trials. The Clinical Trial Consulting Team provides support for trial design in rare diseases leveraging these data. The PRO and Endpoints Consortium develops shorter-term endpoints while capturing the patient-reported significance of interventions under study. The Quality Initiatives and Education/Engagement cores elevate the level of care for patients. The Data Coordinating Center manages the analysis and operations of the Institute. CONCLUSION: By engaging with patients, academia, industry, and patient advocate community representatives, including our Patient Advisory Board, NACI strives for better outcomes and treatments using evidence-based support for clinical trial design.

Assessing the Hydrogeomorphic Effects of Environmental Flows using Hydrodynamic Modeling.

Water managers are increasingly using environmental flows (e-flows) as a tool to improve ecological conditions downstream from impoundments. Recent studies have called for e-flow approaches that explicitly consider impacts on hydrogeomorphic processes when developing management alternatives. Process-based approaches are particularly relevant in river systems that have been highly modified and where water supplies are over allocated. One-dimensional (1D) and two-dimensional (2D) hydrodynamic models can be used to resolve hydrogeomorphic processes at different spatial and temporal scales to support the development, testing, and refinement of e-flow hypotheses. Thus, the objective of this paper is to demonstrate the use of hydrodynamic models as a tool for assisting stakeholders in targeting and assessing environmental flows within a decision-making framework. We present a case study of e-flows on the Rio Chama in northern New Mexico, USA, where 1D and 2D hydrodynamic modeling was used within a collaborative process to implement an e-flow experiment. A specific goal of the e-flow process was to improve spawning habitat for brown trout by flushing fine sediments from gravel features. The results revealed that the 2D hydrodynamic model provided much greater insight with respect to hydrodynamic and sediment transport processes, which led to a reduction in the recommended e-flow discharge. The results suggest that 2D hydrodynamic models can be useful tools for improving process understanding, developing e-flow recommendations, and supporting adaptive management even when limited or no data are available for model calibration and validation.

The use of the CR-10 scale to allow self-regulation of isometric exercise intensity in pre-hypertensive and hypertensive participants.

PURPOSE: Isometric exercise (IE) has been shown to lower blood pressure (BP). Using equipment with force output displays, intensity is usually regulated at 30% maximal voluntary contraction (MVC); however, the cost of programmable equipment and their requirement for maximal contractions presents limitations. A simple, cost-effective alternative deserves investigation. The purpose of this study was (1) to explore the relationship between %MVC, change in systolic BP (ΔSBP), and perceived exertion (CR-10) and (2) to assess the validity of self-regulation of intensity during isometric hand-grip exercise. METHODS: Fourteen pre-hypertensive and hypertensive adults completed eight, 2-min isometric hand-grip exercises at randomised intensities; participants estimated their perceived exertion at 30-s intervals (estimation task). Subsequently, on three separate occasions, participants performed four 2-min contractions at an exertion level that they perceived to be equivalent to CR-10 "Level-6" (production task). RESULTS: There were significant linear relationships between the estimated exertion on the CR-10 scale, and ΔSBP (r = 0.784) and %MVC (r = 0.845). Level-6 was equivalent to an average ΔSBP of 38 mmHg (95% CI; 44, 32 mmHg) and a relative force of 33% MVC (95% CI; 36.2, 30%). During the production task, %MVC was not significantly different between the estimation task and each production trial. In at least the first two repetitions of each production trial, ΔSBP was significantly lower than that observed in the estimation task. CONCLUSION: These findings show that CR-10 "Level-6" is an appropriate method of self-regulating isometric hand-grip intensity; its use offers an affordable and accessible alternative for isometric exercise prescription aimed at reducing BP.

Exploring the performance reserve: Effect of different magnitudes of power output deception on 4,000 m cycling time-trial performance.

PURPOSE: The aim of the present study was to investigate whether a magnitude of deception of 5% in power output would lead to a greater reduction in the amount of time taken for participants to complete a 4000 m cycling TT than a magnitude of deception of 2% in power output, which we have previously shown can lead to a small change in 4000 m cycling TT performance. METHODS: Ten trained male cyclists completed four, 4000 m cycling TTs. The first served as a habituation and the second as a baseline for future trials. During trials three and four participants raced against a pacer which was set, in a randomized order, at a mean power output equal to 2% (+2% TT) or 5% (+5% TT) higher than their baseline performance. However participants were misled into believing that the power output of the pacer was an accurate representation of their baseline performance on both occasions. Cardiorespiratory responses were recorded throughout each TT, and used to estimate energy contribution from aerobic and anaerobic metabolism. RESULTS: Participants were able to finish the +2% TT in a significantly shorter duration than at baseline (p = 0.01), with the difference in performance likely attributable to a greater anaerobic contribution to total power output (p = 0.06). There was no difference in performance between the +5% TT and +2% TT or baseline trials. CONCLUSIONS: Results suggest that a performance reserve is conserved, involving anaerobic energy contribution, which can be utilised given a belief that the exercise will be sustainable however there is an upper limit to how much deception can be tolerated. These findings have implications for performance enhancement in athletes and for our understanding of the nature of fatigue during high-intensity exercise.

Reproducibility of 24-h ambulatory blood pressure and measures of autonomic function.

Determining the number of familiarization sessions required for accurate recordings of ambulatory blood pressure monitoring and autonomic function is a prerequisite for the appropriate design of intervention studies. The benefit of familiarization trials remains largely unexplored. The objective of the current investigation was to assess the reproducibility of 24-h ambulatory blood pressure, 24-h heart rate variability (HRV) and resting measurements of HRV and blood pressure variability (BPV). Eleven prehypertensive and hypertensive adults participated. Ambulatory blood pressure and HRV were measured across 24 h on four occasions. In addition, 5-min resting measures of HRV and BPV were recorded and analysed. Variability between consecutive pairs of trials was calculated. The typical error induced by ambulatory recordings of systolic blood pressure reduced over time (3.8-2.8 mmHg). The greatest effect of familiarization was observed at night. Ambulatory HRV was more reproducible than resting measures. The most reproducible markers were root mean square of successive differences [coefficient of variation (CV): 13.2-10%] and high frequency normalized units (CV: 15.2-6.4%), with the percentage of adjacent NN intervals differing by more than 50 ms showing the poorest reproducibility (CV: 23.9-20.7%). Overall BPV (SD) was more reproducible than the frequency domain low frequency component. Familiarization trials are required for the most accurate recordings of both 24-h ambulatory blood pressure monitoring and HRV. Ambulatory HRV provide superior reproducibility to resting measurements.

Regime shifts and panarchies in regional scale social-ecological water systems.

In this article we summarize histories of nonlinear, complex interactions among societal, legal, and ecosystem dynamics in six North American water basins, as they respond to changing climate. These case studies were chosen to explore the conditions for emergence of adaptive governance in heavily regulated and developed social-ecological systems nested within a hierarchical governmental system. We summarize resilience assessments conducted in each system to provide a synthesis and reference by the other articles in this special feature. We also present a general framework used to evaluate the interactions between society and ecosystem regimes and the governance regimes chosen to mediate those interactions. The case studies show different ways that adaptive governance may be triggered, facilitated, or constrained by ecological and/or legal processes. The resilience assessments indicate that complex interactions among the governance and ecosystem components of these systems can produce different trajectories, which include patterns of (a) development and stabilization, (b) cycles of crisis and recovery, which includes lurches in adaptation and learning, and (3) periods of innovation, novelty, and transformation. Exploration of cross scale (Panarchy) interactions among levels and sectors of government and society illustrate that they may constrain development trajectories, but may also provide stability during crisis or innovation at smaller scales; create crises, but may also facilitate recovery; and constrain system transformation, but may also provide windows of opportunity in which transformation, and the resources to accomplish it, may occur. The framework is the starting point for our exploration of how law might play a role in enhancing the capacity of social-ecological systems to adapt to climate change.

Asymmetry of Cerebral Hemodynamic Response to Incremental Cycling Exercise.

PURPOSE: Exercise is known to result in hemodynamic changes in the bilateral prefrontal cortex. The aim of this study was to investigate hemodynamic changes in right and left hemispheres of the prefrontal cortex (PFC) during incremental cycling exercise. METHODS: After 10 min rest, 9 participants (mean age 26.6 ± 2.5 y, mass 77.5 ± 9.7 kg, stature 1.79 ± 0.9 m) cycled at 100-150 W for 4 min. Thereafter, resistance was increased by 25 W every 4 min until exhaustion (EXH). Respiratory exchange and concentrations of oxy- ([HbO2]), deoxy- ([(HHb]), and total hemoglobin ([Hb(tot)]) in the PFC were continuously measured. Data were averaged for 60 s at rest and preceding ventilatory threshold 1 (VT1), VT2, and volitional EXH and after 5 min recovery. Subjective ratings of affect were measured at VT1, VT2, VT1 minus 25 W (VT1-25W), and VT2 plus 25 W (VT2+25W). RESULTS: There were no between-hemispheres differences in [HbO2] or [Hb(tot)] at rest, VT1, or recovery or in [HHb] at any point. Right-hemisphere [HbO2] and [Hb(tot)] were significantly greater than left at VT2 (P = .01 and P = .02) and EXH (P = .03 and P = .02). Affect was significantly greater at VT1-25W vs VT2 and VT2+25W and at VT1 and VT2 vs VT2+25W (P < .01-.03). CONCLUSIONS: To the authors' knowledge, this is the first study to describe an exercise-state-dependent change in PFC asymmetry during incremental exercise. The asymmetry detected coincided with a decrease in affect scores in agreement with the PFC-asymmetry hypothesis.

Rasch modeling and confirmatory factor analysis of the systemizing quotient-revised (SQ-R) scale.

This study assessed the dimensionality of the Systemizing Quotient-Revised (SQ-R), a measure of how strong a person's interest is in systems, using two statistical approaches: Rasch modeling and Confirmatory Factor Analysis (CFA). Participants included N = 675 with an autism spectrum condition (ASC), N = 1369 family members of people with ASC, and N = 2014 typical controls. Data were applied to the Rasch model (Rating Scale) using WINSTEPS. The data fit the Rasch model quite well lending support to the idea that systemizing could be seen as unidimensional. Reliability estimates were .99 for items and .92 for persons. A CFA parceling approach confirmed that a unidimensional model fit the data. There was, however, differential functioning by sex in some of these items. An abbreviated 44-item version of the scale, consisting of items without differential item functioning by sex was developed. This shorter scale also was tested from a Rasch perspective and confirmed through CFA. All measures showed differences on total scale scores between those participants with and without ASC (d = 0.71, p < .005), and between sexes (d = 0.53, p < .005). We conclude that the SQ-R is an appropriate measure of systemizing which can be measured along a single dimension.

Central and peripheral fatigue in male cyclists after 4-, 20-, and 40-km time trials.

PURPOSE: Few studies have assessed neuromuscular fatigue after self-paced locomotor exercise; moreover, none have assessed the degree of supraspinal fatigue. This study assessed central and peripheral fatigue after self-paced exercise of different durations. METHODS: Thirteen well-trained male cyclists completed 4-, 20-, and 40-km simulated time trials (TTs). Pre- and immediately post-TT (<2.5 min), twitch responses from the knee extensors to electrical stimulation of the femoral nerve and transcranial magnetic stimulation of the motor cortex were recorded to assess neuromuscular and corticospinal function. RESULTS: Time to complete 4-, 20-, and 40-km TTs was 6.0 ± 0.2, 31.8 ± 1.0, and 65.8 ± 2.2 min at average exercise intensities of 96%, 92%, and 87% of maximum oxygen uptake, respectively. Exercise resulted in significant reductions in maximum voluntary contraction, with no difference between TTs (-18%, -15%, and -16% for 4-, 20-, and 40-km TTs, respectively). Greater peripheral fatigue was evident after 4-km (40% reduction in potentiated twitch) compared with that after 20-km (31%) and 40-km TTs (29%). In contrast, longer TTs were characterized by more central fatigue, with greater reductions in voluntary activation measured by motor nerve (-11% and -10% for 20- and 40-km TTs vs -7% for 4-km TTs) and cortical stimulation (-12% and -10% for 20- and 40-km vs -6% for 4-km). CONCLUSIONS: These data demonstrate that fatigue after self-paced exercise is task dependent, with a greater degree of peripheral fatigue after shorter higher-intensity (6 min) TTs and more central fatigue after longer lower-intensity TTs (>30 min).

Rasch modeling and confirmatory factor analysis of the systemizing quotient-revised (SQ-R) scale

This study assessed the dimensionality of the Systemizing Quotient-Revised (SQ-R), a measure of how strong a person's interest is in systems, using two statistical approaches: Rasch modeling and Confirmatory Factor Analysis (CFA). Participants included N = 675 with an autism spectrum condition (ASC), N = 1369 family members of people with ASC, and N = 2014 typical controls. Data were applied to the Rasch model (Rating Scale) using WINSTEPS. The data fit the Rasch model quite well lending support to the idea that systemizing could be seen as unidimensional. Reliability estimates were .99 for items and .92 for persons. A CFA parceling approach confirmed that a unidimensional model fit the data. There was, however, differential functioning by sex in some of these items. An abbreviated 44-item version of the scale, consisting of items without differential item functioning by sex was developed. This shorter scale also was tested from a Rasch perspective and confirmed through CFA. All measures showed differences on total scale scores between those participants with and without ASC (d = 0.71, p < .005), and between sexes (d = 0.53, p < .005). We conclude that the SQ-R is an appropriate measure of systemizing which can be measured along a single dimension (AU)

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The influence of surface roughness on ultrasonic thickness measurements.

In corrosion assessment, ultrasonic wall-thickness measurements are often presented in the form of a color map. However, this gives little quantitative information on the distribution of the thickness measurements. The collected data can be used to form an empirical cumulative distribution function (ECDF), which provides information on the fraction of the surface with less than a certain thickness. It has been speculated that the ECDF could be used to draw conclusions about larger areas, from inspection data of smaller sub-sections. A detailed understanding of the errors introduced by such an approach is required to be confident in its predictions. There are two major sources of error: the actual thickness variation due to the morphology of the surface and the interaction of the signal processing algorithm with the recorded ultrasonic signals. Parallel experimental and computational studies were performed using three surfaces, generated with Gaussian height distributions. The surfaces were machined onto mild steel plates and ultrasonic C-scans were performed, while the distributed point source method was used to perform equivalent simulations. ECDFs corresponding to each of these surfaces (for both the experimental and computational data) are presented and their variation with changing surface roughness and different timing algorithms is discussed.