Scandium-catalyzed chemoselective carbene insertion into N-H over S-H: access to o-alkylamine-diaryl disulfides.

Herein, we report a scandium-catalyzed chemoselective carbene insertion into a N-H bond over a S-H bond with disulfide formation. This reaction represents the first example of the synthesis of o-alkylamine-diaryl disulfides through the N-alkylation of o-aminobenzenethiol, while also undergoing oxidative coupling to form a S-S bond. Control experiments explain the chemo-selectivity of this rare-earth-metal Lewis acid-induced catalysis by a carbene outer-sphere nucleophilic addition mechanism. This method holds tremendous potential as a valuable tool for functionalizing advanced-synthetic-intermediates, offering numerous applications in medicinal and materials chemistry.

Physical education teaching mode assisted by artificial intelligence assistant under the guidance of high-order complex network.

This study explores the integration of artificial intelligence (AI) teaching assistants in sports tennis instruction to enhance the intelligent teaching system. Firstly, the applicability of AI technology to tennis teaching in schools is investigated. The intelligent teaching system comprises an expert system, an image acquisition system, and an intelligent language system. Secondly, employing compressed sensing theory, a framework for learning the large-scale fuzzy cognitive map (FCM) from time series data, termed compressed sensing-FCM (CS-FCM), is devised to address challenges associated with automatic learning methods in the designed AI teaching assistant system. Finally, a high-order FCM-based time series prediction framework is proposed. According to experimental simulations, CS-FCM demonstrates robust convergence and stability, achieving a stable point with a reconstruction error below 0.001 after 15 iterations for FCM with various data lengths and a density of 20%. The proposed intelligent system based on high-order complex networks significantly improves upon the limitations of the current FCM model. The advantages of its teaching assistant system can be effectively leveraged for tennis instruction in sports.

FeCl3-catalyzed oxidative amidation of benzylic C-H bonds enabled by a photogenerated chlorine-radical.

Herein, we report the development of iron-catalyzed benzylic C-H oxidative amidation reactions via photoinduced ligand-to-metal charge transfer (LMCT). These reactions exhibit a broad substrate scope (60 examples) and offer operationally simple, scalable procedures for accessing valuable products from methylarenes in a single step. Mechanistic studies and control experiments confirm the participation of a photogenerated chlorine radical in facilitating the hydrogen atom transfer (HAT) from the benzylic C-H bond to initiate the reaction.

Chemoselective Condensation of 3-Amino-2-cyclohexenones with Cinnamaldehydes: Switchable Synthesis of Dihydroquinolinones and Hexahydroacridinediones.

Herein, a chemoselective condensation of 3-amino-2-cyclohexenones and cinnamaldehydes for switchable synthesis of dihydroquinolinones and hexahydroacridinediones was developed. Mechanism analysis showed that the formation of dihydroquinolinones involved trimolecular condensation and oxidative aromatization, while the formation of hexahydroacridinediones involved acid hydrolysis of enaminone and dehydration-aromatization. This strategy provides a convenient way to switch from the same substrates to produce two different quinolinone derivatives.

Effects of different forms of practicing a sport on athletes' nerve function / Efeitos de diferentes modos de prática de um esporte no desempenho neural de atletas / Efectos de diferentes modos de práctica de un deporte en el desempeño neural de atletas

ABSTRACT Introduction: Poor reaction time can cause irritability, easier distractions, and interfere with normal activities that require concentration. Objective: To study the impact of simulated hypoxic training on the immune system of female middle- and long-distance runners. Methods: Observation of 50 female middle- and long-distance runners living high and training low (HiHiLo) in regard to changes in CD3+, CD4+, CD8+, NK cells and NKT cells during the process of living low and training high (LoHi). Research indicates: HiHiLo training does have a significant effect on these indicators to enhance the antioxidant capacity of the brain and nervous system. Results: Living high and training low (HiHiLo) can improve the excitability of the nervous system of long-distance endurance athletes and has a very significant impact on the stability of the nervous system. This improves cardiopulmonary function under hypoxic conditions and has a role in promoting the ability to mobilize the skeletal muscles. Conclusions: It has been proved that different forms of exercise can effectively improve the athlete's nervous response. Level of evidence II; Therapeutic studies - investigation of treatment results.

RESUMO Introdução: Um tempo de reação precário pode levar a irritabilidade, falta de concentração, e interferir em atividades diárias que exigem raciocínio. Objetivo: Estudar o impacto de treinamento hipóxico simulado no sistema imune de corredoras de média e longa distância. Métodos: Observação de 50 corredoras de média e longa distância que vivem em elevadas altitudes e treinam em baixas altitudes (HiHiLo) quanto a mudanças em CD3+, CD4+, CD8+, células NK e NKT, durante o processo de viver em regiões de baixa altitude e treinar em regiões de alta atitude (LoHi). A pesquisa indica que o treino HiHiLo tem um efeito significativo nesses indicadores no que diz respeito ao aumento da capacidade antioxidante do cérebro e do sistema nervoso. Resultados: O treino HiHiLo pode aumentar a excitação do sistema nervoso de atletas de resistência e longa distância, e tem um impacto muito significativo na estabilidade do sistema nervoso. Isso traz melhorias à função cardiopulmonar em condições de hipóxia e age de modo a promover a habilidade de movimentar os músculos esqueléticos. Conclusões: Foi provado que diferentes tipos de exercício podem efetivamente aprimorar a resposta nervosa de atletas. Nível de evidência II; Estudos terapêuticos - investigação de resultados de tratamento.

RESUMEN Introducción: Un tiempo de reacción precario puede causar irritabilidad, falta de concentración e interferir en actividades diarias que exigen raciocinio. Objetivo: Estudiar el impacto de entrenamiento hipóxico simulado en el sistema inmune de corredores de media y larga distancia. Métodos: Observación de 50 corredores de media y larga distancia que viven en altitudes elevadas y entrenan en altitudes bajas (HiHiLo) en relación con los cambios en las células CD3+, CD4+, CD8+, NK y NKT durante el proceso de vivir en regiones de baja altitud y entrenar en regiones de alta actitud (LoHi). La investigación indica que el entrenamiento HiHiLo tiene un efecto significativo sobre estos indicadores en lo que respecta al aumento de la capacidad antioxidante del cerebro y del sistema nervioso. Resultados: El entrenamiento HiHiLo puede aumentar la excitación del sistema nervioso de atletas de resistencia y larga distancia y tiene un impacto significativo en la estabilidad del sistema nervioso. Esto aporta mejorías en la función cardiopulmonar en condiciones de hipoxia y actúa favoreciendo en la capacidad de movimiento de los músculos esqueléticos. Conclusiones: Fue probado que diferentes tipos de ejercicio pueden efectivamente mejorar la respuesta nerviosa de atletas. Nivel de evidencia II; Estudios terapéuticos - investigación de resultados de tratamiento.

Amide-Assisted Rearrangement of Hydroxyarylformimidoyl Chloride to Diarylurea.

A novel amide-assisted rearrangement reaction of hydroxybenzimidoyl chloride has been established for the efficient synthesis of 1,3-diphenylurea derivatives. A variety of electronically and sterically different 1,3-diphenylurea derivatives can be obtained in good to excellent yields, and a proposed reaction mechanism is also presented.