Achievement of Target Gain Larger than Unity in an Inertial Fusion Experiment

On December 5, 2022, an indirect drive fusion implosion on the National Ignition Facility (NIF) achieved a target gain G_{target} of 1.5. This is the first laboratory demonstration of exceeding "scientific breakeven" (or G_{target}>1) where 2.05 MJ of 351 nm laser light produced 3.1 MJ of total fusion yield, a result which significantly exceeds the Lawson criterion for fusion ignition as reported in a previous NIF implosion [H. Abu-Shawareb et al. (Indirect Drive ICF Collaboration), Phys. Rev. Lett. 129, 075001 (2022)PRLTAO0031-900710.1103/PhysRevLett.129.075001]. This achievement is the culmination of more than five decades of research and gives proof that laboratory fusion, based on fundamental physics principles, is possible. This Letter reports on the target, laser, design, and experimental advancements that led to this result.

Assessing and Improving Data Integrity in Web-Based Surveys: Comparison of Fraud Detection Systems in a COVID-19 Study

BACKGROUND

Web-based surveys increase access to study participation and improve opportunities to reach diverse populations. However, web-based surveys are vulnerable to data quality threats, including fraudulent entries from automated bots and duplicative submissions. Widely used proprietary tools to identify fraud offer little transparency about the methods used, effectiveness, or representativeness of resulting data sets. Robust, reproducible, and context-specific methods of accurately detecting fraudulent responses are needed to ensure integrity and maximize the value of web-based survey research.

OBJECTIVE

This study aims to describe a multilayered fraud detection system implemented in a large web-based survey about COVID-19 attitudes, beliefs, and behaviors; examine the agreement between this fraud detection system and a proprietary fraud detection system; and compare the resulting study samples from each of the 2 fraud detection methods.

METHODS

The PhillyCEAL Common Survey is a cross-sectional web-based survey that remotely enrolled residents ages 13 years and older to assess how the COVID-19 pandemic impacted individuals, neighborhoods, and communities in Philadelphia, Pennsylvania. Two fraud detection methods are described and compared: (1) a multilayer fraud detection strategy developed by the research team that combined automated validation of response data and real-time verification of study entries by study personnel and (2) the proprietary fraud detection system used by the Qualtrics (Qualtrics) survey platform. Descriptive statistics were computed for the full sample and for responses classified as valid by 2 different fraud detection methods, and classification tables were created to assess agreement between the methods. The impact of fraud detection methods on the distribution of vaccine confidence by racial or ethnic group was assessed.

RESULTS

Of 7950 completed surveys, our multilayer fraud detection system identified 3228 (40.60%) cases as valid, while the Qualtrics fraud detection system identified 4389 (55.21%) cases as valid. The 2 methods showed only "fair" or "minimal" agreement in their classifications (κ=0.25; 95% CI 0.23-0.27). The choice of fraud detection method impacted the distribution of vaccine confidence by racial or ethnic group.

CONCLUSIONS

The selection of a fraud detection method can affect the study's sample composition. The findings of this study, while not conclusive, suggest that a multilayered approach to fraud detection that includes conservative use of automated fraud detection and integration of human review of entries tailored to the study's specific context and its participants may be warranted for future survey research.

Lawson Criterion for Ignition Exceeded in an Inertial Fusion Experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion.

Mapping LGBTQ+ Youth Resource Density Across Four High HIV Prevalence Corridors in the US

INTRODUCTION

Studies using geospatial data to understand LGBTQ+-friendly sexual health and wellness resource availability have often focused on services catered to adults. While HIV rates have increased in adolescents in recent years, few studies have explored disparities in resource access for adolescent gay and bisexual men (AGBMSM).

METHODS

We used geospatial data of resources (collected and verified 2017-2018) from the iReach app to understand disparities in resource access for AGBMSM within and between 4 high HIV prevalence corridors in the US.

RESULTS

AGBMSM in non-metro areas had access to fewer resources and some rural counties had no LGBTQ+ -friendly resources. Corridors comprising states with legacies of punitive laws targeting sexual and gender minorities demonstrate stark geographic disparities across the US.

CONCLUSIONS

Policy-makers must understand the granularity of disparities within regions. Online resources may be able to surmount LGBTQ+ resource deserts. However, physical access to LGBTQ+ -friendly services must be improved as a fundamental strategy for reducing HIV among AGBMSM.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13178-021-00660-0.

A homozygous truncating variant in GDF9 in siblings with primary ovarian insufficiency

Premature or primary ovarian insufficiency (POI) affects approximately 1% of women and can be due to a variety of causes. Genetic causes include syndromic and non-syndromic POI. There are several promising candidate genes for whom a clear Mendelian association with non-syndromic POI has not yet been conclusively established, including GDF9. GDF9 is an oocyte-secreted factor and is part of the TGF-beta superfamily of morphogens. It has an important role in follicular development and granulosa cell maturation. We report the case of two siblings with primary ovarian insufficiency (POI) and a homozygous truncating variant in GDF9 (c.604C>T; p.(Gln202*). This report helps establish a clear gene-disease association between GDF9 and POI and argues for routine evaluation for GDF9 variants in patients undergoing genomic investigation for POI.

Portable high-resolution automated 3D imaging for footwear and tire impression capture

The forensic science community raised the need for improved evidence recognition, collection, and visualization analytical instrumentation for field and laboratory use. While the 3D optical techniques for imaging static objects have been extensively studied, there is still a major gap between current knowledge and collecting high-quality footwear and tire impression evidence. Among optical means for 3D imaging, digital fringe projection (DFP) techniques reconstruct 3D shape from phase information, achieving camera-pixel spatial resolution. This paper presents a high-resolution 3D imaging technology using DFP techniques dedicated to footwear and tire impression capture. We developed fully automated software algorithms and a graphical user interface (GUI) that allow anyone without training to operate for high-quality 3D data capture. We performed accuracy evaluations and comparisons comparing with the commercial high-end 3D scanner and carried out qualitative tests for various impressions comparing with the current practices. Overall, our technology achieves similar levels of accuracy and resolution with a high-end commercially available 3D scanner, while having the merits of being (1) more affordable; (2) much easier to operate; and (3) more robust. Compared with the current practice of casting, our technology demonstrates its superiority because it (1) is non-destructive; (2) collects more evidence detail than casts, especially when an impression is fragile; (3) requires less time and money to collect each piece of evidence; and (4) results in a digital file that can easily be shared with other examiners.

Tuberculosis in the Circumpolar Region, 2006-2012

SETTING

The northern circumpolar jurisdictions Canada (Northwest Territories, Nunavik, Nunavut, Yukon), Finland, Greenland, Norway, Russian Federation (Arkhangelsk), Sweden and the United States (Alaska).

OBJECTIVE

To describe and compare demographic, clinical and laboratory characteristics, including drug resistance and treatment completion, of tuberculosis (TB) cases in the northern circumpolar populations.

DESIGN

Descriptive analysis of all active TB cases reported from 2006 to 2012 for incidence rate (IR), age and sex distribution, sputum smear and diagnostic site characteristics, drug resistance and treatment completion rates.

RESULTS

The annual IR of TB disease ranged from a low of 4.3 per 100 000 population in Northern Sweden to a high of 199.5/100 000 in Nunavik, QC, Canada. For all jurisdictions, IR was higher for males than for females. Yukon had the highest proportion of new cases compared with retreatment cases (96.6%). Alaska reported the highest percentage of laboratory-confirmed cases (87.4%). Smear-positive pulmonary cases ranged from 25.8% to 65.2%. Multidrug-resistant cases ranged from 0% (Northern Canada) to 46.3% (Arkhangelsk). Treatment outcome data, available up to 2011, demonstrated >80% treatment completion for four of the 10 jurisdictions.

CONCLUSION

TB remains a serious public health issue in the circumpolar regions. Surveillance data contribute toward a better understanding and improved control of TB in the north.

Reducing HIV Vulnerability Through a Multilevel Life Skills Intervention for Adolescent Men (The iREACH Project): Protocol for a Randomized Controlled Trial

Background

Few HIV interventions have demonstrated efficacy in reducing HIV risk among adolescent men who have sex with men (AMSM), and fewer still have recognized the unique needs of AMSM based on race/ethnicity or geographical setting. Recognizing that youths’ HIV vulnerability is intricately tied to their development and social context, delivering life skills training during adolescence might delay the onset or reduce the consequences of risk factors for HIV acquisition and equip AMSM with the skills to navigate HIV prevention. This protocol describes the development and testing of iREACH, an online multilevel life skills intervention for AMSM.

Objective

This randomized controlled trial (RCT) aims to test the efficacy of an online-delivered life skills intervention, iREACH, on cognitive and behavioral HIV-related outcomes for AMSM.

Methods

iREACH is a prospective RCT of approximately 600 cisgender adolescent males aged 13 to 18 years who report same-sex attractions. The intervention will be tested with a racial/ethnically diverse sample (≥50% racial/ethnic minority) of AMSM living in four regions in the United States: (1) Chicago to Detroit, (2) Washington, DC to Atlanta, (3) San Francisco to San Diego, and (4) Memphis to New Orleans.

Results

This project is currently recruiting participants. Recruitment began in March 2018.

Conclusions

iREACH represents a significant innovation in the development and testing of a tailored life skills-focused intervention for AMSM, and has the potential to fill a significant gap in HIV prevention intervention programming and research for AMSM.

Registered Report Identifier

RR1-10.2196/10174

The mechanism producing initial transients on the clarinet

In self-sustained instruments, starting transients are important timbral characteristics that help identify the instrument and the playing style. Often, the oscillation starts as a growing exponential. This study investigates the starting amplitude of this exponential for the clarinet. After a rapid tongue release, the reed quickly returns to its equilibrium position. The sudden change in aperture produces an abrupt change in both the airflow into the mouthpiece and the mouthpiece pressure. This perturbation travels along the bore and reflects at the open end. Returning to the mouthpiece with slight attenuation, the perturbation can be amplified by the reed acting as an active element-effectively a negative resistance. When the reed release time exceeds the time for sound to travel twice the bore length, the airflow and pressure wave into the bore via the aperture are superposed over their own returning reflection. Measurements of reed motion and mouthpiece pressures during reed release yield values that are used in a model to calculate waveforms showing similarities to those observed experimentally. The initial amplitude decreases with increasing reed release time, though not always monotonically. It can become very small in special cases due to synchronisation between the initial pulse and its reflection.

Incidental Finding of an Aorto-Right Atrial Fistula in a Patient Undergoing Repair of a Sinus of Valsalva Aneurysm

A sinus of Valsalva aneurysm is a rare malformation of the aortic root that can fistulize to another cardiac structure such as the right atrium. Although transthoracic echocardiography and computed tomography angiography have demonstrated utility for the diagnosis of a sinus of Valsalva-to-right atrial fistula, there are few cases where a misdiagnosis may occur. Intraoperative transesophageal echocardiography may be an essential imaging tool for the diagnosis and management of incidental findings such as a sinus of Valsalva-to-right atrial fistula during cardiac surgery and should be used routinely.

Proficiency of nerve conduction using standard methods and reference values (Cl. NPhys Trial 4)

INTRODUCTION

The Cl. NPhys Trial 3 showed that attributes of nerve conduction (NC) were without significant intraobserver differences, although there were significant interobserver differences.

METHODS

Trial 4 tested whether use of written instructions and pretrial agreement on techniques and use of standard reference values, diagnostic percentile values, or broader categorization of abnormality could reduce significant interobserver disagreement and improve agreement among clinical neurophysiologists.

RESULTS

The Trial 4 modifications markedly decreased, but did not eliminate, significant interobserver differences of measured attributes of NC. Use of standard reference values and defined percentile values of abnormality decreased interobserver disagreement and improved agreement of judgment of abnormality among evaluators. Therefore, the same clinical neurophysiologist should perform repeat NCs of therapeutic trial patients.

CONCLUSIONS

Differences in interobserver judgment of abnormality decrease with use of common standard reference values and a defined percentile level of abnormality, providing a rationale for their use in therapeutic trials and medical practice.

Hypoglossal nerve dysfunction and sleep-disordered breathing after stroke

OBJECTIVE

This cross-sectional study of acute ischemic stroke patients examined relationships between hypoglossal nerve conduction, sleep-disordered breathing (SDB), and its severity.

METHODS

Patients within 7 days of stroke underwent nocturnal respiratory monitoring with the ApneaLink device and hypoglossal nerve conduction studies.

RESULTS

Eighteen of 52 subjects (35% [95% confidence interval: 22%, 49%]) had an abnormal hypoglossal amplitude and 23 (44% [95% confidence interval: 30%, 59%]) had an abnormal hypoglossal latency. No differences were identified in hypoglossal nerve latency or amplitude between those with (n = 26) and without (n = 26) significant SDB, defined by an apnea-hypopnea index ≥ 15. However, hypoglossal nerve conduction latency was associated (linear regression p < 0.05) with SDB severity as reflected by the apnea-hypopnea index.

CONCLUSIONS

Acute ischemic stroke patients have a high prevalence of hypoglossal nerve dysfunction. Further studies are needed to explore whether hypoglossal nerve dysfunction may be a cause or consequence of SDB in stroke patients and whether this association can provide further insight into the pathophysiology of SDB in this population.

Homelessness and money mismanagement in Iraq and Afghanistan veterans

OBJECTIVES

We examined the empirical link between money mismanagement and subsequent homelessness among veterans.

METHODS

We used a random sample of Iraq and Afghanistan War era veterans from the National Post-Deployment Adjustment Survey in 2009-2011.

RESULTS

Veterans were randomly selected from a roster of all US military service members in Operation Iraqi Freedom or Operation Enduring Freedom who were separated from active duty or in the Reserves/National Guard. Veterans (n = 1090) from 50 states and all military branches completed 2 waves of data collection 1 year apart (79% retention rate). Thirty percent reported money mismanagement (e.g., bouncing or forging a check, going over one's credit limit, falling victim to a money scam in the past year). Multivariate analysis revealed money mismanagement (odds ratio [OR] = 4.09, 95% CI = 1.87, 8.94) was associated with homelessness in the next year, as were arrest history (OR = 2.65, 95% CI = 1.33, 5.29), mental health diagnosis (OR = 2.59, 95% CI = 1.26, 5.33), and income (OR = 0.30, 95% CI = 0.13, 0.71).

CONCLUSIONS

Money mismanagement, reported by a substantial number of veterans, was related to a higher rate of subsequent homelessness. The findings have implications for policymakers and clinicians, suggesting that financial education programs offered by the US Departments of Defense and Veterans Affairs may be targeted to effectively address veteran homelessness.

A trial of proficiency of nerve conduction: greater standardization still needed

INTRODUCTION

The aim of this study was to test the proficiency (accuracy among evaluators) of measured attributes of nerve conduction (NC).

METHODS

Expert clinical neurophysiologists, without instruction or consensus development, from 4 different medical centers, independently assessed 8 attributes of NC in 24 patients with diabetes mellitus (DM) on consecutive days.

RESULTS

No significant intraobserver differences between days 1 and 2 were found, but significant interobserver differences were seen. Use of standard reference values did not correct for these observed differences.

CONCLUSIONS

Interobserver variability was attributed to differences in performance of NC. It was of sufficient magnitude that it is of concern for the conduct of therapeutic trials. To deal with interrater variability in therapeutic trials, the same electromyographers should perform all NC assessments of individual patients or, preferably, NC procedures should be more standardized. A further trial is needed to test whether such standardization would eliminate interobserver variability.

Hypoglossal nerve conduction findings in obstructive sleep apnea

Denervation of oropharyngeal muscles in obstructive sleep apnea (OSA) has been suggested by needle electromyography (EMG) and muscle biopsy, but little is known about oropharyngeal nerve conduction abnormalities in OSA. We sought to compare hypoglossal nerve conduction studies in patients with and without OSA. Unilateral hypoglossal nerve conduction studies were performed on 20 subjects with OSA and 20 age-matched controls using standard techniques. Median age was 48 years in OSA subjects and 47 years in controls. Hypoglossal compound muscle action potential (CMAP) amplitudes were significantly reduced (P = 0.01, Wilcoxon signed-rank test), but prolongation of latencies in OSA subjects did not reach significance in comparison to those of controls. Among a subgroup of subjects without polyneuropathy (15 pairs), reduced amplitudes in OSA subjects retained borderline significance (P = 0.05). Hypoglossal nerve conduction abnormalities may distinguish patients with OSA from controls. These abnormalities could potentially contribute to, or arise from, OSA.