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在业余比赛中,更多的人喜欢站在底线那里等待对手的失误,但往往对手还没有失误自己却由于体力不支而先行缴械。所以对于业余球员来讲,合理运用发球抢攻战术能够节省宝贵的体力,并主动逼迫对手出现失误。 相似文献
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如果你有一个坏名字,那可真是后患无穷。通用汽车的品牌“NOVA”,在英语里面好听,但在西班牙语中它是“走不动”的意思,所以在那些说西班牙语的拉丁美洲国家中这一款车无人问津 相似文献
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Youngmann Brit Yom-Tov Elad Gilad-Bachrach Ran Karmon Danny 《Information Retrieval》2021,24(3):205-239
Information Retrieval Journal - Search advertising, a popular method for online marketing, has been employed to improve health by eliciting positive behavioral change. However, writing effective... 相似文献
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PROBLEM: Various demographic and familial risk factors have been linked to runaway behavior. To date, there has not been a systematic investigation of the impact of size of community on runaway behavior. This study will compare runaways from smaller cities and rural areas to their urban counterparts. METHODS: A convenience sample of 602 adolescents was interviewed between 1995 and August of 1996 in Missouri, Iowa, Nebraska, and Kansas, USA. Multiple regression was used to examine the association between gender, neglect, sexual abuse, physical abuse, geographic and family structure change, and community size of first runaway to predict age at first runaway, deviant subsistence strategies, and street victimization. RESULTS: Findings indicate that adolescents exposed to neglect (beta=-.20) and sexual abuse (beta=-.16) ran away sooner and were more likely to be victimized on the street. Rural adolescents who experienced higher levels of physical abuse relied more heavily on deviant subsistence strategies (beta=.15) and remained in abusive homes longer (beta=.15) than their similarly situated urban counterparts. CONCLUSIONS: Rural youth who have been subjected to elevated levels of familial abuse are at greater risk of deviant subsistence strategies, which increase the likelihood of street victimization. 相似文献
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Recent studies show that reduction in cross-sectional area can be used to improve the concentration factor in microscale bioseparations. Due to simplicity in fabrication process, a step reduction in cross-sectional area is generally implemented in microchip to increase the concentration factor. But the sudden change in cross-sectional area can introduce significant band dispersion and distortion. This paper reports a new fabrication technique to form a gradual reduction in cross-sectional area in polymethylmethacrylate (PMMA) microchannel for both anionic and cationic isotachophoresis (ITP). The fabrication technique is based on hot embossing and surface modification assisted bonding method. Both one-dimensional and two-dimensional gradual reduction in cross-sectional area microchannels were formed on PMMA with high fidelity using proposed techniques. ITP experiments were conducted to separate and preconcentrate fluorescent proteins in these microchips. Thousand fold and ten thousand fold increase in concentrations were obtained when 10 × and 100 × gradual reduction in cross-sectional area microchannels were used for ITP. 相似文献