Design and fabrication of a focus-tunable liquid cylindrical lens based on electrowetting.

In this study, a focus-tunable liquid cylindrical lens based on electrowetting was designed and fabricated. The cylindrical cavity usually used in common electrowetting zoom spherical lenses was replaced by a 20 mm × 10 mm × 8 mm cuboid cavity, in which the interface of two liquids formed a toroid owing to the electrowetting effect. The proposed liquid cylindrical lens can serve as either a converging or diverging lens with the response time under 110 ms by changing the supplied voltage. The zoom lens we fabricated worked stably under 0-110 V voltage for a long time, guaranteeing that the focal length of the liquid cylindrical lens can range within (-∞, -148.36 mm) ∪ (697.21 mm, +∞). By combining the liquid lens that we designed with a simple fixed cylindrical lens, a cylindrical lens system with an arbitrary focal length suitable for various tasks in beam manipulation can be realized.

Analysis of Methods to Reduce Jogging Injuries from the Perspective of Risk Cognition.

Objectives: Injuries are common events that impair the function of joggers; it is important to take effective measures to reduce the incidence of jogging injuries to maximize its benefits. Methods: We collected questionnaires from 3468 Chinese exercisers using a stratified random sampling method. We analyzed these data using AMOS 22.0 (IBM) and SPSS 26.0 (IBM). Results: We constructed a relationship model of jogging risk cognition, jogging risk behaviors, and jogging injury incidence, and the indicators fit well. The path coefficient between jogging risk cognition and jogging risk behaviors of joggers was -0.64; the path coefficient between jogging risk behaviors and jogging injuries incidence was 0.44; and the path coefficient between jogging risk cognition and jogging injuries incidence was -0.23. Conclusions: The higher the level of jogging risk cognition of joggers, the lower their jogging risk behaviors, leading to a lower incidence of jogging injuries. Based on the generally low level of jogging risk cognition of joggers, the construction of a jogging risk cognitive education system that can be integrated into universities, middle schools and primary schools, as well as family, school and society, is conducive to comprehensively improve the level of jogging risk cognition of joggers.

Risk perception and behavior status of college students extracurricular jogging exercise / 中国学校卫生

Objective@#To explore the relationship among jogging risk perception, jogging risk behavior and the incidence of jogging risk, so as to provide a feasible way to reduce the risk of college students extracurricular jogging exercise.@*Methods@#The method of convenience sampling was used to conduct a follow up survey among 470 college students at a university in Beijing participating in extracurricular jogging exercise and the sports world campus app was used to record and monitor jogging exercise. During the tracking period, the jogging related information was counted once a month, a total of 6 times. At the same time, three questionnaires were distributed in three stages to collect relevant information. SPSS 26.0 was used for the descriptive analysis, and AMOS 22.0 was used for correlational analysis.@*Results@#The risk rate of extracurricular jogging exercise of college students during the past academic year was 71.06 %, score of knowledge on jogging risk was(3.68±0.59), was (3.25±0.91)for jogging injury, and was( 3.23± 0.96)for jogging related disease. Significant negative correlation between college students jogging risk perception and jogging risk behavior ( r =-0.34), negative correlation between jogging risk perception and the incidence of jogging injuries ( r =-0.27), and positive correlation between jogging risk behavior and the incidence of jogging injuries ( r =0.28) were observed( P <0.01). PE(physical education) class was the main way of obtaining the knowledge about jogging risks among college students(43.40%). @*Conclusion@#College students show high vulnerability for extracurricular jogging related risks, and low level of perception of jogging risks and jogging injuries. Relevant measures need to be taken to improve the cognitive level of running risk among college students, so as to reduce the incidence of running risk.

Cardiovascular control responses in high intensity exercise stress tests / Respostas de controle cardiovascular em testes de estresse de exercícios de alta intensidade / Respuestas de control cardiovascular en pruebas de estrés de ejercicios de alta intensidad

ABSTRACT Introduction: High intensity exercise is an important factor to achieve the best exercise effect, and is closely related to the patient's safety and rehabilitation. Objective: To investigate the effects of high intensity exercise on cardiovascular response and substance and energy metabolism. Methods: 50 male students at a university were selected. The average age of the subjects was 23 years old. Process of the experiment: Before the experiment, each subject took routine warm-up activities first, then put on the experimental equipment and began to run 100 meters. At the same time, the subjects' heart rate, blood oxygen parameters and exercise time were recorded. After passing the finish line, a period of heart rate recording and blood oxygen parameters were continued. Results: Anaerobic metabolism was the main activity in the 100m race. The first 7s after the start of the race, there is a non-lactic acid process without oxygen metabolism, and the muscle oxygen saturation curve presents little change. Conclusions: High intensity exercise in sports training and physical exercise can lead to reduced heart rate variability. The increased incidence of various arrhythmias should be based on the actual situation of the movement of the object, and a reasonable arrangement of exercise load intensity. Level of evidence II; Therapeutic studies - investigation of treatment results.

RESUMO Introdução: Exercícios de alta intensidade são um importante fator para alcançar o melhor efeito de exercícios, e está estreitamente ligado a segurança e reabilitação do paciente. Objetivo: Investigar os efeitos de exercícios de alta intensidade na resposta cardiovascular e no metabolismo de substâncias e energia. Métodos: 50 estudantes do sexo masculino em uma universidade foram selecionados. A idade média dos sujeitos do estudo era de 23 anos. Processo do experimento: Antes de iniciar, primeiramente, cada estudante fez aquecimentos de rotina. Após, colocaram o equipamento experimental e começaram a correr 100 metros. Ao mesmo tempo, a frequência cardíaca, parâmetros de oxigenação do sangue e tempo do exercício foram registrados. Após passar a linha de chegada, continuou-se a registrar a frequência cardíaca e os parâmetros de oxigenação do sangue por um tempo. Resultados: O metabolismo anaeróbico foi a atividade principal na corrida de 100 metros. Nos sete segundos após o início da corrida, há um processo ácido não láctico sem a metabolização de oxigênio e a curva de saturação de oxigênio do músculo apresenta pouca alteração. Conclusões: Exercícios de alta intensidade no treinamento esportivo e o exercício físico pode levar à variabilidade reduzida de frequência cardíaca. O aumento na incidência de várias arritmias deve se basear na situação real de movimento do sujeito e um manejo razoável da intensidade da carga do exercício. Nível de evidência II; Estudos terapêuticos - investigação de resultados de tratamento.

Resumen Introducción: Ejercicios de alta intensidad son un importante factor en alcanzar el mejor efecto de ejercicio, y está estrechamente relacionado a la seguridad y rehabilitación del paciente. Objetivo: Investigar los efectos de ejercicios de alta intensidad en la respuesta cardiovascular y en el metabolismo de sustancias y energía. Métodos: Se seleccionó 50 estudiantes del sexo masculino en una universidad. La edad media de los sujetos del estudio era de 23 años. Proceso del experimento: Antes de empezar, primeramente, cada estudiante hizo calentamientos de rutina. Después, pusieron el aparato experimental y empezaron a correr 100 metros. Al mismo tiempo, se registró la frecuencia cardíaca, parámetros de oxigenación de la sangre y el tiempo del ejercicio. Después de pasar la línea de llegada, se continuó a registrar la frecuencia cardíaca y los parámetros de oxigenación de la sangre por un tiempo. Resultados: El metabolismo anaeróbico fue la actividad principal en la carrera de 100 metros. 7 segundos tras el comienzo de la carrera, hay un proceso ácido no láctico sin la metabolización de oxígeno y la curva de saturación de oxígeno del músculo presenta poca alteración. Conclusiones: Ejercicios de alta intensidad en el entrenamiento deportivo y el ejercicio físico puede llevar a la variabilidad reducida de frecuencia cardíaca. El aumento en la incidencia de varias arritmias debe basarse en la situación real de movimiento del sujeto y un manejo razonable de la intensidad de carga del ejercicio. Nivel de evidencia II; Estudios terapéuticos - investigación de resultados de tratamiento.

Jogging-related Risk Cognition and the Stimulation of Risky Behavior during Jogging.

Objectives: With the rapid increase in the number of Chinese joggers, the number of people incurring injuries from jogging also has increased. Evaluating the relationship between jogging-related risk cognition and risky behaviors while jogging will help improve jogging-related risk cognition among joggers. Methods: We collected questionnaires about jogging-related risky behaviors and risk cognition from 3468 Chinese exercisers using a stratified random sampling method. We analyzed these data with correlation and multi-linear regression analyses. Results: The regression coefficients between risk cognition related to jogging-related technical procedures and risky behavior, between risk cognition related to personal physical and mental conditions and risky behavior, between risk cognition related to jogging-related equipment factors and risky behavior, between risk cognition related to jogging-related environmental factors and risky behavior, and between risk cognition related to personal jogging competition-related factors and risky behavior were all negative and statistically significant (p < .05). Conclusions: The level of risk cognition related to jogging is negatively correlated with actual risky behavior during jogging, which indicates that the higher the level of jogging-related risk cognition, the fewer jogging-related risky behaviors occur.