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某化学小组同学,用如图所示的实验探究质量守恒定律

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    Weekend gym rats might be onto something. Weekend warriors, who put recommended amounts of exercise into one or two gym sessions(时段), experience similar health benefits to those who work out several times a week, according to a new study. And those benefits include a longer life. “It is encouraging news that working out in just one or two days per week is connected to a lower risk of demise, even among people who do some activities but don't quite meet recommended exercise levels,” the lead researcher Emmanuel Stamatakis says in a statement.

    The World Health Organization recommends that adults perform two and a half hours of moderate-intensity(中等强度的)physical exercise, or an hour and 25 minutes of more energetic exercise per week. Usually this is done within several days, with experts suggesting that adults get up to 30 minutes of regular exercise each day. However, the new study suggests that busy people may be able to meet the standards when they have more free time, such as at weekends, and stay healthy all the same.

    Researchers studied data from more than 63,000 men and women in England and Scotland, including data about their activity habits and risks for death. The researchers put each individual in one of four groups: those who described themselves as inactive, those who exercised but less than what was recommended, those who exercised in the “weekend warrior” style, and those who worked out regularly more than three days a week.

    Adults who exercised in the “weekend warrior” style had a 40 percent lower risk of cardiovascular(心血管的)disease and a 30 percent lower risk of death by any cause than those who did not exercise at all. The lower risks of cardiovascular disease and overall death were similar to the risks of people who worked out regularly over the week.

    But take a pause before you give up your weekday gym habit. Just a couple of light sessions won't be enough to get benefits: “Weekend warrior” exercise sessions are usually 75-minute energetic workouts, according to the study.

    The results are promising overall, if you just simply can't fit physical activities into most days. The key here is that exercise is truly a lifeline(救生索): It reduces your risk of illnesses like heart disease, diabetes, cancer and depression, according to the WHO. So, if you are just too busy on weekdays, let go of the guilt(内疚). Just make sure to hit the gym hard at weekends.

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阅读材料,回答问题。

材料一:在古代中国,从男尊女卑的观念出发,统治者制定了一整套法律、伦理道德的原则,用以规范和限制女性的行为……中国古代把“主内”作为对女性的角色定位,把相夫教子作为女性的天职……。

——摘编自《中国古代社会女性的独特贡献》

材料二:19世纪末,中产阶级的女性地位发生了变化,人们对中产阶级女性的主要期待不再是做家务,而是做母亲。书刊杂志和社会舆论都在宣传这样一种观念:母亲应该关心全家人的身心健康……人们也期待着母亲们能够保留传统的美德和保持女性的特点。油画《贝尔利一家》中……作为丈夫和父亲的男人坐在桌子前的椅子上,这暗示着他是与事业和家外的世界相连的;而作为妻子和母亲的女人站在孩子们中间,则表明她处于“主内”地位。

——《19世纪英国中产阶级家庭文化探析》

材料三:“口红效应”这一20世纪30年代提出的理论也在海外媒体上不断亮相。所谓“口红效应”是指在美国,每当经济不景气时,口红的销量反而会直线上升。……在经济不景气的情况下,人们仍然会有强烈的消费欲望,所以会转而购买比较廉价的商品。尤其是战争期间,政府和传媒都鼓励妇女们涂抹着口红进入工厂或军队,唇间一抹亮丽的红色成了鼓舞士气的法宝。由于大工厂多转产战备物质,各个时装公司纷纷承担起口红生产的任务,这保证了口红在战争期间的供应。美国海军特地开办培训课程,让女兵们学习,如何快速完美地化妆,同时还规定,从军女性的口红颜色必须与她们制服上红色臂章和帽子上红色细绳相搭配。

——《美丽与禁忌:口红的历史》