Strong polarization mode coupling in microresonators

We observe strong modal coupling between the TE00 and TM00 modes in Si3N4 ring resonators revealed by avoided crossings of the corresponding resonances. Such couplings result in significant shifts of the resonance frequencies over a wide range around the crossing points. This leads to an effective dispersion that is one order of magnitude larger than the intrinsic dispersion and creates broad windows of anomalous dispersion. We also observe the changes to frequency comb spectra generated in Si3N4 microresonators due polarization mode and higher-order mode crossings and suggest approaches to avoid these effects. Alternatively, such polarization mode-crossings can be used as a novel tool for dispersion engineering in microresonators.Comment: Comments are very welcome (send to corresponding author

Translating Research Into Practice: Speeding the Adoption of Innovative Health Care Programs

Looks at case studies of four innovative clinical programs to determine key factors influencing the diffusion and adoption of innovations in health care

Demographics and the Cost of Pharmaceuticals in a Private Third-Party Prescription Program

Objective: To compare variance in the cost of pharmaceuticals attributable to demographic variables with variance explained by plan characteristics, using prescription claims data within various therapeutic categories, and to examine differences in average cost of pharmaceuticals among demographic variables after controlling for covariates. Design: Retrospective, cross-sectional study. Data Collection: Data for this study were obtained from 1996 prescription claims information for the commercial population administered by a Rhode Island-based pharmacy benefit management (PBM) company. Six therapeutic categories with the highest expenditures were analyzed. Information on claims for six drug categories was extracted using database management software. Statistical analyses using multiple regression and analysis of covariance were carried out. Results: Plan characteristics outperformed demographic variables sixteenfold for all drug categories combined in explaining variance in cost of pharmaceuticals among plan enrollees. Average cost of pharmaceuticals differed among demographic variables such as age, gender, location, and place of employment after controlling for average wholesale price and days supply. Conclusions: The results obtained in this study have practical significance in the determination of capitation rates when utilization history of prospective members is not available. In this situation, managed care organizations (MCOs) or PBMs may have to set capitation rates based solely on eligibility data. Significant differences in average drug costs among the members based on place of employment suggest that benefit managers should consider differentiating capitation rates according to their clients\u27 businesses. Finally, the data from this study indicated that commercial members residing in Tennessee had the lowest average cost of pharmaceuticals among all states evaluated. The fact that one PBM manages more than 80% of the TennCare prescription program along with a significant commercial client base suggests that a spillover effect may exist

Mechanistic Modeling of Microtopographic Impacts on CO2 and CH4 Fluxes in an Alaskan Tundra Ecosystem Using the CLM-Microbe Model

Spatial heterogeneities in soil hydrology have been confirmed as a key control on CO2 and CH4 fluxes in the Arctic tundra ecosystem. In this study, we applied a mechanistic ecosystem model, CLM-Microbe, to examine the microtopographic impacts on CO2 and CH4 fluxes across seven landscape types in Utqiaġvik, Alaska: trough, low-centered polygon (LCP) center, LCP transition, LCP rim, high-centered polygon (HCP) center, HCP transition, and HCP rim. We first validated the CLM-Microbe model against static-chamber measured CO2 and CH4 fluxes in 2013 for three landscape types: trough, LCP center, and LCP rim. Model application showed that low-elevation and thus wetter landscape types (i.e., trough, transitions, and LCP center) had larger CH4 emissions rates with greater seasonal variations than high-elevation and drier landscape types (rims and HCP center). Sensitivity analysis indicated that substrate availability for methanogenesis (acetate, CO2 + H2) is the most important factor determining CH4 emission, and vegetation physiological properties largely affect the net ecosystem carbon exchange and ecosystem respiration in Arctic tundra ecosystems. Modeled CH4 emissions for different microtopographic features were upscaled to the eddy covariance (EC) domain with an area-weighted approach before validation against EC-measured CH4 fluxes. The model underestimated the EC-measured CH4 flux by 20% and 25% at daily and hourly time steps, suggesting the importance of the time step in reporting CH4 flux. The strong microtopographic impacts on CO2 and CH4 fluxes call for a model-data integration framework for better understanding and predicting carbon flux in the highly heterogeneous Arctic landscape

Perfect imaging: they don't do it with mirrors

Imaging with a spherical mirror in empty space is compared with the case when the mirror is filled with the medium of Maxwell's fish eye. Exact time-dependent solutions of Maxwell's equations show that perfect imaging is not achievable with an electrical ideal mirror on its own, but with Maxwell's fish eye in the regime when it implements a curved geometry for full electromagnetic waves

Disparities in eating disorder risk and diagnosis among sexual minority college students: Findings from the national Healthy Minds Study

ObjectiveTo examine differences in eating disorder (ED) risk and diagnosis by sexual orientation in a national sample of college students.MethodData from 178 U.S. colleges and universities participating in the Healthy Minds Study between 2016 and 2019 were analyzed (36,691 cisgender men, 81,730 cisgender women; 15.7% self‐identifying as sexual minorities). Outcomes were ED risk (≥2 on the SCOFF) and self‐reported lifetime ED diagnosis. Prevalence estimates adjusted for demographics and weight status were computed via logistic regression.ResultsHigher proportions of questioning (29.1%), bisexual (26.3%), and gay men (30.9%) exhibited elevated risk than heterosexual men (14.3%), and a higher proportion of gay men exhibited elevated risk than bisexual men. Higher proportions of questioning (34.5%) and bisexual women (34.6%) exhibited elevated risk than heterosexual women (27.6%); proportions of lesbian (28.1%) and heterosexual women were similar. Among those with elevated risk, higher proportions of bisexual (5.0%) and gay men (7.1%) and of questioning (14.7%), bisexual (18.1%), and lesbian women (19.6%) had been diagnosed relative to heterosexual men (2.0%) and heterosexual women (10.3%), respectively.DiscussionQuestioning and bisexual individuals appear to be particularly vulnerable; they may experience elevated ED risk relative to their heterosexual peers yet underdiagnosis relative to their gay or lesbian peers.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/162796/2/eat23304_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/162796/1/eat23304.pd

Disclosure of Maternal HIV Status to Children: To Tell or Not To Tell . . . That Is the Question

HIV-infected mothers face the challenging decision of whether to disclose their serostatus to their children. From the perspective of both mother and child, we explored the process of disclosure, providing descriptive information and examining the relationships among disclosure, demographic variables, and child adjustment. Participants were 23 mothers and one of their noninfected children (9 to 16 years of age). Sixty-one percent of mothers disclosed. Consistent with previous research, disclosure was not related to child functioning. However, children sworn to secrecy demonstrated lower social competence and more externalizing problems. Differential disclosure, which occurred in one-third of the families, was associated with higher levels of depressive and anxiety symptoms. Finally, knowing more than mothers had themselves disclosed was related to child maladjustment across multiple domains. Clinical implications and the need for future research are considered