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Notwithstanding the expansion of higher education across the OECD, there continues to be concern about the levels of participation amongst those from disadvantaged backgrounds. In response to this, a new form of financial support for students from low-income families, the 'opportunity bursary', was introduced for a limited period in England from 2001/02. Surveys of two cohorts of opportunity-bursary applicants were carried out and these suggested possible psychological, behavioural and economic impacts. Fewer opportunity-bursary recipients than non-recipients reported that part-time work had interfered with their studies and more reported that the bursary had made them less worried about meeting the costs of going to university. There was some evidence that the scheme led to increased retention in the first year of university study; it also appeared to lead to lower levels of debt, in particular bank overdrafts or credit card debt.  相似文献   
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The results of Del Rosario on cold emission are shown to result from the fact that, through the attainment of specially good vacuum conditions and freedom from contamination, the cold electron current from the wire was suppressed up to field strengths greater than those at which measurable current was obtained in the work of previous observers. It was in fact suppressed beyond the point at which discharge started from points on the welding of the support. The results of Del Rosario are thus probably characteristic of conditions other than those pertaining to the wire, a conclusion which accounts for his current voltage curves. The formula of Fowler and Nordheim is found to apply in the measurable regions in form directly and in magnitude only if irregularities of the surface are such as to raise the field at the surface to a sufficiently high value. Breakdowns after intense heat treatment are studied and found to be caused by immeasurably small currents of electrons knocking ions from the anode. The erratic original curves obtained by previous investigators are found to be caused by successive breakdowns similar to those found after intense heating.  相似文献   
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