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试述金融在现代经济中的地位和作用。

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Children attending schools located in high-traffic zones have a 45 percent increased risk of developing asthma, even though time spent at school only accounts for about one-third of a child’s waking hours, according to new research. Asthma is the most common chronic childhood illness in developed countries and has been linked to environmental factors such as traffic-related air pollution. "While residential traffic-related pollution has been associated with asthma, there has been little study of the effects of traffic exposure at school on new onset asthma," says Rob McConnell, professor of preventive medicine at USC’s Keck School of Medicine. "Exposure to pollution at locations other than home, especially where children spend a large portion of their day and may engage in physical activity, appears to influence asthma risk as well." The study appears online in the journal Environmental Health Perspectives. The study drew upon data from the Children’s Health Study (CHS), a longitudinal study of children in Southern California communities that was designed to investigate the chronic effects of air pollution on respiratory health. Using a cohort of 2 497 kindergarten and first grade children who were asthma-free when they entered the study, researchers examined the relationship of local traffic around schools and homes to diagnosis new onset asthma that occurred during three years of follow-up. Traffic-related pollution exposure was assessed based on a model that took into account traffic volume, distance to major roadways from home and school and local weather conditions. Regional ambient ozone, nitrogen dioxide (二氧化氮) and particulate matter were measured continuously at one central site in each of the 13 study communities. The design allowed investigators to examine the joint effects of local traffic-related pollution exposure at school and at home and of regional pollution exposure affecting the entire community. Researchers found 120 cases of new asthma. The risk associated with traffic-related pollution exposure at schools was almost as high as for residential exposure, and combined exposure accounting for time spent at home and at school had a slightly larger effect. Although children spend less time at school than at home, physical education, and other activities that take place at school may increase ventilation rates and the dose of pollutants getting into the lungs, McConnell notes. Traffic-related pollutant levels may also be higher during the morning hours when children are arriving at school. Despite a state law that prohibits school districts from building campuses within 500 feet of a freeway, many Southern California schools are located near high-traffic areas, including busy surface streets. "It’s important to understand how these micro-environments where children spent a lot of their time outside of the home are impacting their health," McConnell says. "Policies that reduce exposure to high-traffic environments may help to prevent this disease. " The study was funded by grants from the National Institute of Environmental Health Sciences, the US Environmental Protection Agency, the South Coast Air Quality Management District, and the Hastings Foundation. We can infer from McConnell’s view that______.

A. there has been little study of the residential traffic-related pollution
B. activities that take place at school may increase the risk of asthma
C. traffic-related pollutant level is lower during the morning hours
D. frequent exposure to outdoors appears to influence the risk of asthma

[问题4] 在默认情况下,图2-23中该数据包请求的服务为 (9) ,提供该服务的服务器IP地址为 (10) 。该服务使用到一次TCP的三次握手过程。根据图2-23中No.栏中的信息,标识TCP连接三次握手过程开始的数据包的标号是 (11) 。该服务与客户机进行通信时,所使用的源端口号是 (12) 。该数据包IP头服务类型的Delay(延迟)标志位的值为 (13) 。

小家电产品出口需取得型式试验报告,首次登记的企业,由当地的检验检疫机构派员从生产批中随机抽取并封存样品,由企业送至国家质检总局指定的实验室进行型式试验。()

A. 对
B. 错

出入境检验检疫部门单独或会同有关主管部门共同负责发放的出口商品质量许可证的工作,未获得质量许可证书的商品不准出口。()

A. 对
B. 错

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