Adiabatic elimination-based coupling control in densely packed subwavelength waveguides.

The ability to control light propagation in photonic integrated circuits is at the foundation of modern light-based communication. However, the inherent crosstalk in densely packed waveguides and the lack of robust control of the coupling are a major roadblock toward ultra-high density photonic integrated circuits. As a result, the diffraction limit is often considered as the lower bound for ultra-dense silicon photonics circuits. Here we experimentally demonstrate an active control of the coupling between two closely packed waveguides via the interaction with a decoupled waveguide. This control scheme is analogous to the adiabatic elimination, a well-known procedure in atomic physics. This approach offers an attractive solution for ultra-dense integrated nanophotonics for light-based communications and integrated quantum computing

Socioeconomic and racial/ethnic inequalities in depression prevalence and the treatment gap in Brazil: A decomposition analysis.

Depression is a major global health burden and there are stark socioeconomic inequalities in both the prevalence of depression and access to treatment for depression. In Brazil, racial/ethnic inequalities are of particular concern, but the factors contributing to these inequalities remain mostly unknown. This paper firstly explores determinants of depression and the treatment gap (i.e., untreated afflicted individuals) in Brazil and identifies if socio-economic and health system factors explain changes over time. Secondly, it analyses income and racial/ethnic inequalities in depression and the treatment gap and identifies factors explaining inequalities through decomposition methods. Data from two waves (2013 and 2019) of a representative household-based survey are used. In 2019, 10.8% of adults were depressed, but over 70% of depressed adults did not receive care. Black or brown/mixed Brazilians were more likely to have untreated depression, and region of residence was the most important determinant of these racial/ethnic inequalities. Notably, 44.6% of the difference in the treatment gap between white individuals and black and brown/mixed individuals was not explained by differences in observables, which could potentially be due to discrimination or difficulties in accessing treatment due to other non-observable characteristics. Employment, age, exposure to violence and physical activity are the main contributing factors to income inequalities in depression. These results suggest that policies aimed at improving the levels of exposure of lower-income individuals to risk factors may positively impact mental health and mental health inequalities, while addressing inequalities in service provision and resourcing for mental health and tackling barriers to access stemming from discrimination are essential to bridge the treatment gap equitably

Inequalities in unmet need for health care services and medications in Brazil: a decomposition analysis

Summary Background Unmet need is a metric used to assess the performance of health care systems throughout the world. One of the primary objectives of the Brazilian health care system is to identify ways to improve the health outcomes of all citizens. To accomplish this challenging goal, the health care system in Brazil will need to identify and eliminate barriers and provide timely and adequate access to health care services to all. Methods This study assessed the performance of the Brazilian health care system by focusing on the unmet need for health care services and medications. We evaluated the Brazilian National Health Survey data collected in 2013 and 2019 to determine the magnitude of socioeconomic-related inequalities associated with unmet health care needs. Primary contributing factors were identified via decomposition analysis of the calculated concentration indices (CInds). Findings Despite the availability of universal health care, 3.8% and 7.5% of the population in Brazil reported unmet needs for health care services and medications, respectively in the 2019 survey. Although the overall unmet need for medications remained unchanged between 2013 and 2019, CInd analysis revealed significant pro-poor inequalities with respect to unmet needs for both health care services and medications. The overall magnitude of these inequalities was higher in the poorer regions of the country. The use of private health insurance as well as individual health and socioeconomic status contributed significantly to the inequalities associated with unmet needs for health care services and medication throughout Brazil. Interpretations Policy interventions should focus on improving access to health care services, extending coverage to include pharmaceuticals, and targeting both financial and non-financial barriers to obtaining care, particularly those experienced by the poor and vulnerable populations in Brazil