Setting Limits on Screen Time for Children (6-to-12 Years): The Integral Role of Parents and Educators.

This paper investigates the effects of screen time on child development and cognition and the setting of ‘safe’ screen time limits for young children, specifically children aged 6-to-12 years. Guidelines on screen time vary across constituencies, and the debate around screen time is contentious with many questions yet to be answered. A review of literature was undertaken to compare current screen time recommendations against the evidence from Neuroscience, Psychiatry, Psychology and Pediatrics that quantify screen time effects on the children's brain development. Based on this comparison, conclusions are made that can guide education policies around ‘remote learning’ and ‘home schooling’ to align them with the available research on the effects of screen time on children and inform a re-evaluation of the role of parents and educators in the setting of ‘safe’ limits on screen time.

Positive impact of the COVID-19 pandemic? A longitudinal study on the impact of the COVID-19 pandemic on physicians’ work experiences and employability

ObjectiveThe COVID-19 pandemic places an enormous demand on physicians around the world. The aim of this study was to examine the impact of the COVID-19 pandemic on physicians’ work experiences and their ability and willingness to continue working in their profession until retirement (ie, their employability).DesignA longitudinal comparative design was used. Survey data were collected on three moments: before (May 2019), in the early phase (May 2020) and in a later phase (November 2020) of the COVID-19 pandemic. Time effects were tested using repeated-measures analyses of variance and one-way analyses of variance.SettingThis study took place among physicians of two hospitals in a large city in the Netherlands.Participants165 hospital physicians with surgical, medical and other specialties participated in this study.ResultsPhysicians’ employability significantly increased from the time prior to the COVID-19 pandemic, compared with the period during this pandemic. Employability differs among physicians with surgical, medical and other specialties. Furthermore, physicians experienced a lower emotional, physical and quantitative workload during the first peak of the COVID-19 pandemic, compared with before the pandemic. Moreover, physicians experienced the most stress from the impact of COVID-19 on their work in general and from combining work and private life.ConclusionsThis study shows that physicians’ employability and work experiences are affected by the COVID-19 pandemic. Work experiences vary for physicians with different specialties. These varieties stress the importance of attention for physicians’ individual needs and challenges regarding working during the COVID-19 pandemic and the possibility of continuing work in the aftermath of this crisis. Based on this, physicians can be offered tailor-made solutions. This is important to maintain a healthy and employable workforce, which is essential for a sustainable healthcare system.

Person, Place, and Time Effects on Cognitive Function Among Older People in Taiwan

Purpose Individual’s factors across time or combined with area characteristics related to cognitive function for older people have been widely explored, but little research examined person, place, and time effects altogether. The purpose of this study was to examine the effects of individuals, cities, and time on older people’s cognitive function in Taiwan. Methods A nation-representative longitudinal individual data were from Taiwan Longitudinal Survey on Aging (TLSA) 1999-2015 panel data (analysis sample n=6349 persons, observations=12042). Cognitive function was scored 0-19. Individual’s factors included demographics, health conditions and health behaviors, mental health and stress, social support and social participation, etc. Eleven city-level indicators were based on 22 cities and data were from the government open data sources. Mixed linear modeling analysis was applied. Results Better cognitive function was significantly related to individuals’ working, ethnicity, younger age, better education level, better self-rated health, less psychological stress, receiving more emotional support, having higher economic satisfaction at the intercept. Sex, ethnicity, age, education, self-rated health, physical function, and social connectedness were significant at the time slope. When controlling for individuals’ factors, population density and green land were significant at the intercept and at the time slope. Interactions of individual- and city-level factors were not significant. Discussion Individual’s social participation and social support are protective factors of cognitive function for older adults. And an age-friendly environment providing appropriate cognitive stimulation and chances of social participation may be beneficial for cognitive function.

Analytical Modeling of Wax Plug Transportation during Pipeline Pigging Using a Foam Pig

Summary In our previous article (Gao et al. 2020), a mathematical model including elastic and yield components but not viscous component was developed to predict the wax plug transportation force. In this work, an analytical model was developed to calculate the wax plug transportation force, and the viscous component was introduced into the analytical model to capture some of the time effects. In this analytical model, the viscoelastic behavior of the wax deposit was characterized by a three-parameter model, formulated by adding an additional spring element to the Kelvin-Voight model. The Laplace transformation was used to solve the model. According to the calculated results of the analytical model, the transportation force of the wax plug was observed to slightly increase with time and then tended to level off. To obtain a parameter in the model and verify the model, the pigging experiments were conducted using foam pigs. During the pigging process of the foam pig, the wax plug transportation force in a five-phase wax removal profile was determined by taking the steady wax breaking force from the resistive force of the wax layer. Moreover, the linear increase of the wax plug transportation force per unit contact area with the shear strength of the wax layer was found, as described by the functional relationship in the analytical model. The interfacial lubrication coefficient calculated from the experimental data based on the analytical model is between the coefficient for diesel-prepared deposits and coefficient for oil-A-prepared deposits. Experimental verification results show that the average relative error of the model is 12.47%. Field implication was proposed to illustrate the application of the model and the formation condition of the wax blockage.

Light Curves Analysis and Period Study of Two Eclipsing Binaries UZ Lyr and BR Cyg

Two eclipsing binary systems UZ Lyr and BR Cyg are the semi-detached types whose secondary component fill its Roche lobe. Although radial velocity and light curves of these systems have already been investigated separately, both radial velocity and light curves of them are analyzed simultaneously for the first time in the present study . Also, the orbital period changes of these systems are studied. Our results show that the mass transfer between components have negligible effects on the orbital period changes of these systems, but two light-time effects are the reasons of the periodic behavior of the O-C curve for UZ Lyr. We could not remark more information about orbital period changes for BR Cyg, but we find a new orbital period for it. By radial velocity and light curves analysis we find a clod spot on the secondary components of BR Cyg. The new geometrical and physical parameters of both systems are obtained and their positions on H-R diagram demonstrated.