First demonstration of a fiber optic bolometer on a tokamak plasma (invited)

A fiber optic bolometer (FOB) was demonstrated observing a fusion plasma for the first time at the DIII-D tokamak. A FOB uses a fiber optics-based interferometric technique that is designed to have a high sensitivity to temperature changes [75 mK/(W/m²) responsivity in high vacuum with 0.38 mK noise level] with a negligible susceptibility to electromagnetic interference (EMI) that can be problematic for resistive bolometers in a tokamak environment. A single-channel test apparatus was installed on DIII-D consisting of a measurement FOB and shielded reference FOB. The single-channel FOB showed a negligible increase in the noise level during typical plasma operations (0.39 mK) compared to the benchtop results (0.38 mK), confirming an insignificant EMI impact to the FOB. Comparisons to DIII-D resistive bolometers showed good agreement with the single-channel FOB, indicating that the FOB is comparable to a resistive bolometer when the impulse calibration is applied. The noise-equivalent power density of the calibrated FOB during a plasma operation was 0.55 W/m² with an average sampling time of 20 ms. The major potential effect of ionizing radiation on the FOB would be the radiation-induced attenuation, which can be efficiently compensated for by adjusting the probing light power.

Understanding Physicians' Preferences for Telemedicine During the COVID-19 Pandemic: Cross-sectional Study

BACKGROUND

In contrast to the current broad dissemination of telemedicine across medical specialties, previous research focused on the effectiveness of telemedicine in special populations and for behavioral health encounters, demonstrating that both physician and patient factors impact the efficacious use of telemedicine.

OBJECTIVE

We aim to evaluate physician perceptions of the appropriateness of telemedicine for patients attending the primary care practices of a federally qualified health center in New York City.

METHODS

We used an anonymous cross-sectional survey including closed- and open-ended questions. We used chi-square to test whether providers from certain specialties were more likely to state they would use telemedicine in the future. We used t tests to compare age between those who would versus would not use telemedicine. We then used logistic regression to test whether age and specialty were both correlated with the desire to use telemedicine in the future. We used thematic content analysis to describe the reasons providers felt they would not want to use telemedicine in the future and to describe the situations for which they felt telemedicine would be appropriate.

RESULTS

Of 272 health care providers who were sent the electronic survey, 157 (58%) responded within the 2-week survey time frame. The mean age of providers was 45 (range 28-75) years. Overall, 80% (126/157) stated they would use telemedicine in the future. Compared to the family medicine, internal medicine, behavioral health, dental, and obstetrics and gynecology specialties, providers from pediatrics, med-peds, subspecialties, and surgery (protelemedicine specialties) were more likely to believe telemedicine would be useful post pandemic (61/67 [91%] vs 65/90 [72%]; P<.001). Providers who reported they would use telemedicine in the future were younger (mean age 44, range 42-46 years vs mean age 50, range 46-55 years; P=.048). In the regression analysis, both protelemedicine specialties and age were significantly associated with odds of reporting they would use telemedicine in the future (prospecialties: odds ratio 5.2, 95% CI 1.7-16.2; younger age: odds ratio 1.05, 95% CI 1.01-1.08). Providers who did not want to use telemedicine in the future cited concerns about inadequate patient care, lack of physical patient interaction, technology issues, and lack of necessity. Providers who felt telemedicine would be useful cited the following situations: follow-up visits, medication refills, urgent care, patient convenience, and specific conditions such as behavioral health, dermatology visits, and chronic care management.

CONCLUSIONS

The majority of health providers in this resource-limited setting in a federally qualified health center believed that telemedicine would be useful for providing care after the pandemic is over.

Potential Financial Impact of Incidental Cardiac Pathology Detected During Lung Cancer Screening

BACKGROUND

Lung cancer screening (LCS) is broadly accepted. Screening also identifies incidental cardiac findings (S findings) that need follow-up. We report the magnitude of the potential downstream revenue generated by appropriate S finding management after 4 years of our free LCS program.

MATERIALS AND METHODS

A retrospective database and chart review of a single-center free LCS program in the underserved southeast were performed. All patients who were enrolled in the screening required a primary care physician (PCP) as part of the decision-making model. Referrals to cardiac specialists for S findings found on LCS were recorded. Cost analysis was performed to track potential downstream revenue generated for the institution based upon Medicare allowable or Diagnosis-related group calculations.

RESULTS

One thousand one hundred thirty-two scans were reviewed with 262 (23%) yielding positive S findings for 1 or more organ systems. 181/262 (69%) patients had cardiac findings, only 64/181 (35%) of these patients were referred to cardiology specialists by the PCP. The total Medicare billable amount for all cardiac referrals/interventions was $284 379, representing 35% of the potential billable amount of $804 260. Percutaneous coronary intervention (PCI) was the highest billable amount at $18 568. Eight percent of the patients undergoing appropriate cardiac evaluation required a PCI. If not for the screening and cardiac specialist referral, this patient group may not have received appropriate cardiovascular diagnosis and treatment.

DISCUSSION

Lung cancer screening also identifies patients with significant cardiac disease, many of whom may not be appropriately referred. Identification and treatment of incidentally noted cardiovascular findings may both improve patient care and justify supporting free LCS programs.

Intense geodesic acousticlike modes driven by suprathermal ions in a tokamak plasma

Intense axisymmetric oscillations driven by suprathermal ions injected in the direction counter to the toroidal plasma current are observed in the DIII-D tokamak. The modes appear at nearly half the ideal geodesic acoustic mode frequency, in plasmas with comparable electron and ion temperatures and elevated magnetic safety factor (q_{min}>or=2). Strong bursting and frequency chirping are observed, concomitant with large (10%-15%) drops in the neutron emission. Large electron density fluctuations (n[over ]_{e}/n_{e} approximately 1.5%) are observed with no detectable electron temperature fluctuations, confirming a dominant compressional contribution to the pressure perturbation as predicted by kinetic theory. The observed mode frequency is consistent with a recent theoretical prediction for the energetic-particle-driven geodesic acoustic mode.

Associations of sociodemographic, psychosocial, and behavioral factors with sexual risk and sexually transmitted diseases in teen clinic patients

PURPOSE

To examine the influence of sociodemographic characteristics, sexually transmitted disease (STD)/human immunodeficiency virus knowledge, and psychosocial and behavioral risk factors on sexual risk and STDs in adolescents using constructs from the Information, Motivation, and Behavioral Skills model (IMB).

METHODS

A convenience sample of 303 sexually experienced, racially diverse adolescents (mean age 16.7 years, 57.9% female) who were seeking health care at a general health maintenance organization teen clinic were recruited for the study and completed a self-reported questionnaire which assessed sociodemographic, knowledge, and psychosocial factors, risk behaviors, and history of STDs. Multiple regression analyses were used to assess factors associated with sexual risk behavior and STD history.

RESULTS

Many of the study participants were at risk for STDs; 43.8% had four or more lifetime sexual partners, 62.8% did not consistently use condoms, 21.1% had a history of pregnancy or impregnation, and 28.2% had a history of STDs. A multiple linear regression model to assess factors associated with sexual risk behavior (a nine-item index) indicate that perceptions of higher STD risk, perceptions that friends engage in risk behaviors, perceptions that friends will not support their STD risk-reduction efforts, knowing someone of a similar age who has had an STD, and having no intention of using condoms in the future are significantly associated with sexual behavioral risk (R(2) =.22, p <.000). A logistic regression model to examine history of STDs reveals that teens who are female, African-American, frequently use marijuana, have an older steady sexual partner, have a history of pregnancy or impregnation, have a greater number of lifetime sexual partners, and perceive that monogamy will not decrease STD risk are significantly more likely to report a history of STDs.

CONCLUSIONS

Sociodemographic factors and constructs of the IMB model are associated with adolescents' risk and acquisition of STDs. Teens with such risk profiles should be targeted for risk-reduction intervention.

Progress in adolescent mental health

This chapter reviews the status of emotional and behavioral problems in adolescents and current issues in their assessment and treatment. The authors emphasize the need for the development of mental health programs for adolescents in natural settings such as schools, and present a conceptual framework for intervention based on provider knowledge of risk and protective factors.