Carotenoid cleavage enzymes evolved convergently to generate the visual chromophore.

The retinal light response in animals originates from the photoisomerization of an opsin-coupled 11-cis-retinaldehyde chromophore. This visual chromophore is enzymatically produced through the action of carotenoid cleavage dioxygenases. Vertebrates require two carotenoid cleavage dioxygenases, β-carotene oxygenase 1 and retinal pigment epithelium 65 (RPE65), to form 11-cis-retinaldehyde from carotenoid substrates, whereas invertebrates such as insects use a single enzyme known as Neither Inactivation Nor Afterpotential B (NinaB).

Evaluation of Veterinary Medical Student Retention of Pre-clinical Concepts with Various Experiential Learning Methods.

Many veterinary medical colleges have undergone curricular changes that have moved away from traditional lecture-based teaching in favor of evidence-based, experiential methods of instruction. Such a curricular reinvention occurred in 2018 at Michigan State University's College of Veterinary Medicine, with individual courses using numerous instructional and learning methods. In the present study, three courses were assessed, two of which used a method of experiential learning, and the other utilizing a traditional lecture approach.

Life Expectancy and COVID-19 in Florida State Prisons.

Introduction: The heightened risk of COVID-19 infection and mortality in prisons is well documented, but COVID-19's impact on all-cause mortality in incarcerated populations has not yet been studied. This study analyzed mortality records from the Florida State Department of Corrections prison system population to evaluate the impact COVID-19 had on all-cause mortality and compare mortality rates and life expectancy with that of the overall state of Florida population.

Methods: Population age and sex data for Florida State Department of Corrections were ascertained from the Florida State Department of Corrections Offender Based Information System.

Assessing the Mortality Impact of the COVID-19 Pandemic in Florida State Prisons.

Background: The increased risk of COVID-19 infection among incarcerated individuals due to environmental hazards is well known and recent studies have highlighted the higher rates of infection and mortality prisoners in the United States face due to COVID-19. However, the impact of COVID-19 on all-cause mortality rates in incarcerated populations has not been studied.

Methods: Using data reported by the Florida Department of Corrections on prison populations and mortality events we conducted a retrospective cohort study of all individuals incarcerated in Florida state prisons between 2015 and 2020.

Certifiable Robustness to Adversarial State Uncertainty in Deep Reinforcement Learning.

Deep neural network-based systems are now state-of-the-art in many robotics tasks, but their application in safety-critical domains remains dangerous without formal guarantees on network robustness. Small perturbations to sensor inputs (from noise or adversarial examples) are often enough to change network-based decisions, which was recently shown to cause an autonomous vehicle to swerve into another lane. In light of these dangers, numerous algorithms have been developed as defensive mechanisms from these adversarial inputs, some of which provide formal robustness guarantees or certificates.

Physical fitness and performance. Training for old age: production functions for the aerobic exercise inputs.

Purpose: This paper attempts to develop production functions (PF) between aerobic exercise inputs and long-run health outputs. Future studies could use such PF for estimating the benefits and costs (broadly defined) of different exercise programs to help develop optimal (utility maximizing) ones.

Methods: To develop the PF, the paper reviewed the biomedical literature for the major dose-response relations between health, physical fitness, and exercise.

Chemical alteration of poly(tetrafluoroethylene) TFE teflon induced by exposure to electrons and inert-gas ions.

In this study the chemical alterations of poly(tetrafluoroethylene) (TFE Teflon) by approximately 1.0-keV electrons and 1.0-keV He and Ar ions have been examined using X-ray photoelectron spectroscopy (XPS).