Theoretical Investigation of the Steric Effects on Alkyne Semihydrogenation Catalyzed by Frustrated Lewis Pairs.

Frustrated Lewis pairs (FLPs) have received increasing attention for offering a distinctive pathway for the activation and conversion of small molecules. Here, we employ density functional calculations to investigate the electronic and steric effects of FLPs and alkynes on the activity toward alkyne semihydrogenation, a crucial reaction in the production of pharmaceuticals and polymers. We investigated the steric effect of FLPs by replacing the LA-LB linker () of the model catalyst FLP, 1-NMe-2-B(CF)-CH (), with various linkers.

Serotonin Toxicity in Children and Adolescents: A Systematic Review and Meta-Analysis of Cases.

Serotonin toxicity is a state of central nervous system (CNS) excitation classically featuring altered mental status, neuromuscular excitation, and autonomic instability. While retrospective studies and reviews have characterized serotonin toxicity in adults, there have been no systematic reviews of serotonin toxicity in pediatric populations. The goal of this review was to use published case reports to describe serotonin toxicity in pediatric patients and to consider the impact of age on clinical presentation.

Nutritional Rickets Due to Severe Food Selectivity in Autism Spectrum Disorder.

Objective: Studies have detected differences in various measures of bone health between individuals with autism spectrum disorder (ASD) and their peers. However, these measures do not amount to direct clinical evidence of increased orthopedic pathology in this population. Some of the most compelling evidence to this effect comes from case reports of nutritional rickets in children with ASD.

Dietary Patterns, Physical Activity, Sleep, and Risk for Dementia and Cognitive Decline.

Purpose Of Review: Diet, physical activity, and sleep are three major modifiable lifestyle factors. This selective review examines the evidence for strong and reliable associations between these three lifestyle factors and risk of dementia and cognitive decline, in an effort to assist clinicians with providing more informed answers to the common questions they face from patients.

Recent Findings: Certain aspects of nutrition can decrease risk for dementia.

Frequency of fetal karyotype abnormalities in women undergoing invasive testing in the absence of ultrasound and other high-risk indications.

Objectives: No previous studies have reported the frequencies of individual chromosomal anomalies in normal-appearing fetuses stratified by maternal age (MA) and gestational age (GA). We therefore sought to (1) characterize the frequency of all fetal karyotype anomalies in sonographically normal appearing fetuses without pretest risk factors, and (2) assess MA and GA impact on the proportion of anomalies targeted by screening and consequent impact on residual risk following a negative result.

Methods: Fetal karyotypes from samples without prior risk assessment or ultrasound anomalies were analyzed.

Roadmap for reform: outlook for imaging under accountable care.

The primary goals of the Patient Protection and Affordable Care Act are to expand insurance coverage through an individual mandate, and to reduce growing healthcare costs through new risk-based payment models and the formation of ACOs. With the high cost of exams and steady growth through the last decade, imaging appears to be a prime target for savings under accountable care. Given that some of the reform payment models are set to begin as early as next year, and private payers are increasingly instituting similar risk-based payment models in their plans, it is critical for imaging leaders to understand how these models will affect their growth strategy and prepare accordingly.