A neural circuit architecture for angular integration in Drosophila.

Many animals keep track of their angular heading over time while navigating through their environment. However, a neural-circuit architecture for computing heading has not been experimentally defined in any species. Here we describe a set of clockwise- and anticlockwise-shifting neurons in the Drosophila central complex whose wiring and physiology provide a means to rotate an angular heading estimate based on the fly's angular velocity. We show that each class of shifting neurons exists in two subtypes, with spatiotemporal activity profiles that suggest different roles for each subtype at the start and end of tethered-walking turns. Shifting neurons are required for the heading system to properly track the fly's heading in the dark, and stimulation of these neurons induces predictable shifts in the heading signal. The central features of this biological circuit are analogous to those of computational models proposed for head-direction cells in rodents and may shed light on how neural systems, in general, perform integration.

A case series of presumed fungal endogenous endophthalmitis in post COVID-19 patients.

The novel coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2, has challenged the medical community. Several ocular manifestations secondary to COVID-19 have been documented. Prolonged hospitalization exposes the patient to various multiresistant bacteria making them prone to various secondary infections. This case series describes four cases of presumed fungal endogenous endophthalmitis in patients who recovered from COVID-19.

To remove the buckle or watch?

Scleral buckling is one of the most effective modality for treatment of rhegmatogenous retinal detachment and in selected cases of retinopathy of prematurity. Although quite safe, it has its own set of associated morbidities. This report presents an interesting case, where the scleral buckle migrated posteriorly reaching up to the optic nerve.

Adolescent daily cigarette smoking: is rural residency a risk factor?

INTRODUCTION: Daily cigarette smoking among US adolescents remains a significant public health problem. Understanding risk is important in order to develop strategies to reduce this type of tobacco use. PURPOSE: The primary objective of this research was to examine whether rural residency is an independent risk factor for being a daily smoker among adolescents ages 12 to 18 years. METHODS: This is a cross-sectional study where univariate, bivariate, and multivariate analyses were performed on a merged 1997-2003 Youth Risk Behavior Surveillance System dataset to determine whether rural residence was a significant risk factor for daily cigarette smoking, after adjusting for demographic factors. RESULTS: Using daily smoking as the dependent variable, initial multivariate analyses revealed that adolescents who lived either in suburban (OR=.34, CI=.32, .36) or urban (OR=.33, CI=.31, .35) locales were less likely to become daily smokers than adolescents living in rural locales. Subsequent logistic regression analysis yielded that rural youths who became daily smokers were more likely to: have used smokeless tobacco products in the past 12 months (OR=1.25, CI=1.04,1.51); be female (OR=1.42, CI=1.23, 1.64); be Caucasian (OR=1.53, CI=1.28, 1.84); have first smoked a whole cigarette when they were 12 years of age or younger (OR=2.08, CI=1.82, 2.38); and have smoked at school in the past 30 days (OR=14.52, CI=11.97, 17.60). CONCLUSIONS: The results indicate that rural residency is a risk factor for tobacco use among US youth.