Evaluation of MEMS-based In-place Inclinometers in Cold Regions

INE/AUTC 12.3

Energetic ion loss diagnostic for the Wendelstein 7-AS stellarator

A diagnostic to measure the loss of energetic ions from the Wendelstein 7-AS (W7-AS) stellarator has been built. It is capable of measuring losses of both neutral beam ions and energetic ions arising from ion cyclotron resonant heating. The probe can measure losses of both clockwise and counterclockwise-going energetic ions simultaneously, and accepts a wide range of pitch angles in both directions. Initial measurements by the diagnostic are reported

Evidence for Community Face Masking to Limit the Spread of SARS-CoV-2: A Critical Review

The use of facemasks in community settings has become an accepted public policy response to decrease disease transmission during the COVID-19 pandemic. Yet evidence of facemask efficacy is based primarily on observational studies that are subject to confounding and on mechanistic studies that rely on surrogate endpoints (such as droplet dispersion) as proxies for disease transmission. The available clinical evidence of facemask efficacy is of low quality and the best available clinical evidence has mostly failed to show efficacy, with fourteen of sixteen identified randomized controlled trials comparing face masks to no mask controls failing to find statistically significant benefit in the intent-to-treat populations. Of sixteen quantitative meta- analyses, eight were equivocal or critical as to whether evidence supports a public recommendation of masks, and the remaining eight supported a public mask intervention on limited evidence primarily on the basis of the precautionary principle. Although weak evidence should not preclude precautionary actions in the face of unprecedented events such as the COVID-19 pandemic, ethical principles require that the strength of the evidence and best estimates of amount of benefit be truthfully communicated to the public

Social Context, Sexual Strategies, and Risks for HIV Transmission among Men who have Sex with Men: The South Beach Health Survey

In a population-based sample of 193 men who had sex with men in South Beach, Miami-Dade County, Florida, two indicators of social context—choice of sexual relationships and perceived HIV-infection status—were used to analyze residents who engaged in certain sexual practices with their partners. The vast majority (88.6%) of respondents reported engagement in anal sex during the previous 12 months; 20.2% reported unprotected anal intercourse (UAI) with ejaculation with any partner and 12.4% reported UAI with ejaculation with one or more casual partners. Findings supported the hypothesis that primary partner relationships and perceived HIV status are important variables for understanding engagement in UAI with ejaculation. Men who engaged in such behaviors with casual partners were more likely to have negative attitudes towards condoms, report difficulty communicating desires for safer sex, disagree with the belief that AIDS is fatal, and be intoxicated during anal intercourse. Men who reported engaging in anal intercourse, but who never shared unprotected ejaculations, were most likely to be unknowingly infected with HIV, suggesting that many men may become infected while following what they believe to be “safer sex practices.” In designing effective interventions, public health authorities need to take into account socially embedded risk-negotiating practices

Solid State Neutral Particle Analyzer Array on NSTX

A Solid State Neutral Particle Analyzer (SSNPA) array has been installed on the National Spherical Torus Experiment (NSTX). The array consists of four chords viewing through a common vacuum flange. The tangency radii of the viewing chords are 60, 90, 100, and 120 cm. They view across the three co-injection neutral beam lines (deuterium, 80 keV (typ.) with tangency radii 48.7, 59.2, and 69.4 cm) on NSTX and detect co-going energetic ions. A silicon photodiode used was calibrated by using a mono-energetic deuteron beam source. Deuterons with energy above 40 keV can be detected with the present setup. The degradation of the performance was also investigated. Lead shots and epoxy are used for neutron shielding to reduce handling any hazardous heavy metal. This method also enables us to make an arbitrary shape to be fit into the complex flight tube

Correlation between excitation of Alfven modes and degradation of ICRF heating efficiency in TFTR

Alfven modes are excited by energetic ions in TFTR during intense minority ICRF heating. There is a clear threshold in rf power above which the modes are destabilized. The net effect of these modes is the increase of the fast ion losses, with an associated saturation of the ion tail energy and of the efficiency of the heating. Typically, several modes are excited with progressive n-numbers, with frequencies in the neighborhood of 200 kHz. Results suggest that Energetic Particle Modes (EPM), mostly unseen by the Mirnov coils, are generated near the center and are responsible for the ion losses. Stronger global TAE modes, which are destabilized by the stream of displaced fast ions, appear responsible only for minor losses