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Sport psychology services to high performance athletes during These are trying times for us all. COVID-19 has altered our lives as citizens. The changes associated with the current pandemic have presented sport and exercise psychologists with many challenges and opportunities related to sport performance, physical activity and health. Here, we focus on what was, and is presently, being encountered by mental performance consultants in relation to the aspiring Olympic athletes they are supporting.Within recent weeks, mental performance consultants working with Olympic aspirants have evidenced a growing number of suggestions how aspiring athletes might proceed in their sports and in their broader lives, based on their national conditions and regional responses to the pandemic. Each national funding agency, Olympic committee, federal government, and sport organisation, is rolling out strategies of how mental performance consultants can work effectively with clients in what for many, but not all, is a socially distanced world.Discussions have varied from the challenges that athletes are encountering to issues associated with social isolation, career disruption, qualification process uncertainty, and unconventional and limited access to effective training environments and training partners. Underpinning these considerations is the health and wellbeing of athletes in their pursuits toward excellence.Historically, editorials within the International Journal of Sport and Exercise Psychology were paired with special issues, such as the one focused on international approaches to Olympic athlete performance, published in 2016. Within the current editorial, however, there is a deviation in approach, caused by a global circumstancesport is not being experienced as usual; the challenges posed for those engaging in sport, region by region, are uncharted.The focus we have set, in what should have been the 2020 Olympic year, is placed on the shared challenges and the emergence of solutions that mental performance consultants are presently undertaking in their work with athletes. The co-authors of this editorial are from Asia, Europe, and North America. We have published on the topic of Olympic performance and we are currently immersed in work with Olympic athletes in our respective countries. What follows is a synthesised commentary.The reader might posit that embedded in each author's work, approaches are idiosyncratic and driven partly by culture and context, which is a correct assumption. For example, some of us are working from a distance, where others are consulting face-to-face. However, what we share in common is astounding, despite our respective locations and circumstances. We present this editorial, structured into three temporal stages: (a) before the 2020 Olympics were postponed, (b) once the Olympics were postponed, and (c) the path being re-set toward Tokyo, 2021. Before Olympic postponementLife tends to be normal before crisis transitions are experienced, within and outside of highperformance sport. Within high-per...

Background Dihydroartemisinin (DHA) has been shown to exert anticancer activity through iron-dependent reactive oxygen species (ROS) generation, which is similar to ferroptosis, a novel form of cell death. However, whether DHA causes ferroptosis in glioma cells and the potential regulatory mechanisms remain unclear. Methods Effects of DHA on the proliferation, cell death, ROS and lipid ROS generation as well as reduced gluthione consumption were assessed in glioma cells with or without ferroptosis inhibitor. The biological mechanisms by which glioma cells attenuate the pro-ferroptotic effects of DHA were assessed using molecular methods. Results DHA induced ferroptosis in glioma cells, as characterized by iron-dependent cell death accompanied with ROS generation and lipid peroxidation. However, DHA treatment simultaneously activated a feedback pathway of ferroptosis by increasing the expression of heat shock protein family A (Hsp70) member 5 (HSPA5). Mechanistically, DHA caused endoplasmic reticulum (ER) stress in glioma cells, which resulted in the induction of HSPA5 expression by protein kinase R-like ER kinase (PERK)-upregulated activating transcription factor 4 (ATF4). Subsequent HSPA5 upregulation increased the expression and activity of glutathione peroxidase 4 (GPX4), which neutralized DHA-induced lipid peroxidation and thus protected glioma cells from ferroptosis. Inhibition of the PERK-ATF4-HSPA5-GPX4 pathway using siRNA or small molecules increased DHA sensitivity of glioma cells by increasing ferroptosis both in vitro and in vivo. Conclusions Collectively, these data suggested that ferroptosis might be a novel anticancer mechanism of DHA in glioma and HSPA5 may serve as a negative regulator of DHA-induced ferroptosis. Therefore, inhibiting the negative feedback pathway would be a promising therapeutic strategy to strengthen the anti-glioma activity of DHA.

When there is parameter uncertainty in the constraints of a convex optimization problem, it is natural to formulate the problem as a joint chance constrained program (JCCP) which requires that all constraints be satisfied simultaneously with a given large probability. In this paper, we propose to solve the JCCP by a sequence of convex approximations. We show that the solutions of the sequence of approximations converge to a Karush-Kuhn-Tuck (KKT) point of the JCCP under a certain asymptotic regime. Furthermore, we propose to use a gradient-based Monte Carlo method to solve the sequence of convex approximations.

Ecological conservation and restoration are necessary to mitigate environmental degradation problems. China has taken great efforts in such actions. To understand the ecological transition during 2000–2010 in China, this study analysed trends in vegetation change using remote sensing and linear regression. Climate and socioeconomic factors were included to screen the driving forces for vegetation change using correlation or comparative analyses. Our results indicated that China experienced both vegetation greening (restoration) and browning (degradation) with great spatial heterogeneity. Socioeconomic factors, such as human populations and economic production, were the most significant factors for vegetation change. Nature reserves have contributed slightly to the deceleration of vegetation browning and the promotion of greening; however, a large-scale conservation approach beyond nature reserves was more effective. The effectiveness of the Three-North Shelter Forest Program lay between the two above approaches. The findings of this study highlighted that vegetation trend detection is a practical approach for large-scale ecological transition assessments, which can inform decision-making that promotes vegetation greening via proper socioeconomic development and ecosystem management.

ObjectivesTo estimate the effectiveness of endoscopic screening programme in reducing incidence and mortality of upper gastrointestinal cancer in high risks areas of China.DesignThis multicentre population-based cohort study was conducted in six areas in China from 2005 to 2015. All permanent residents aged 40 to 69 years were identified as target subjects. We refer to those who were invited for screening collectively as the invited group. Of these, we classify those who were invited and undertook endoscopic screening as the screened group and those who were invited but did not accept screening as the non-screened group. Target subjects who were not invited to the screening were assigned to the control group. The effectiveness of the endoscopic screening and screening programme were evaluated by comparing reductions in incidence and mortality from upper gastrointestinal cancer in the screened and invited group with control group.ResultsOur cohort analysis included 637 500 people: 299 483 in the control group and 338 017 in the invited to screening group, 113 340 (33.53%) of whom were screened eventually. Compared with subjects in the control group, upper gastrointestinal cancer incidence and mortality decreased by 23% (relative risk (RR)=0.77, 95% CI 0.74 to 0.81) and 57% (RR=0.43, 95% CI 0.40 to 0.47) in the screened group, respectively, and by 14% (RR=0.86, 95% CI 0.84 to 0.89) and 31% (RR=0.69, 95% CI 0.66 to 0.72) in the invited group, respectively.ConclusionAmong individuals aged 40 to 69 years in high risk areas of upper gastrointestinal cancer, one-time endoscopic screening programme was associated with a significant decrease in upper gastrointestinal cancer incidence and mortality.