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The goals of today's school athletic programs are vastly different from the original intentions of the administrators who established the first interscholastic athletic teams. For athletics to be anything more than a drain on school and taxpayer resources, these programs must undergo serious changes.  相似文献   
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Surprisingly few studies have looked at people's understanding of skeletons. Most of the work in this field that has been done has only involved children's understanding of human skeletons. This study looks at students' understandings of the structure of animal (including human) skeletons. A crosssectional approach was used involving a total of 175 students in England from six different age groups (ranging from 4 year olds to 20 year olds). Students were presented, on separate occasions, with specimens of a brown rat, a starling and a herring and asked to draw what they thought was inside each specimen. On a final occasion, they were also asked to draw what they thought was inside themselves. Repeated inspections of the completed drawings allowed us to construct a seven point scale of 'skeletal understanding'. Our analysis shows the extent to which student understanding increases with age and the degree to which pupils know more about human than other skeletons. The findings are interpreted with reference to current trends in English science curricula and pedagogy. We comment in particular on the current inability of most students to see the skeleton as a functional, integrated whole.  相似文献   
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Arming uninhabited vehicles (UVs) is an increasing trend. Widespread deployment can bring dangers for arms-control agreements and international humanitarian law (IHL). Armed UVs can destabilise the situation between potential opponents. Smaller systems can be used for terrorism. Using a systematic definition existing international regulation of armed UVs in the fields of arms control, export control and transparency measures is reviewed; these partly include armed UVs, but leave large gaps. For preventive arms control a general prohibition of armed UVs would be best. If that is unattainable, several measures should be taken. An explicit prohibition of autonomous attack, that is without a human decision, should be added to IHL. Concerning armed UVs remotely controlled by a human soldier, recommendations differ according to type or mission. New kinds of uninhabited nuclear-weapon carriers should be banned. Space weapons should be prohibited in general. UVs smaller than 0.2–0.5 m should be banned. Bigger remotely controlled armed UVs not equipped with weapons of mass destruction should be subject to numerical limitations in various categories. For these the Treaty on Conventional Armed Forces in Europe is an important precedent.  相似文献   
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