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With the introduction of the internal marketthe health service is changing rapidly and health libraries must change with it. Many libraries arerequested to cost their services. The demand comes from external customers and from their ownorganizations. This paper discusses the various reasons for costing services and howcosting information can influence our management decision making. The paper challengeslibrarians to move costing processes away from a mechanistic approach, towards a means ofdemonstrating the worth of a library resources unit in cost and qualitative terms. Using costinginformation for cost control purposes, comparison of cost with other providers, setting prices ordetermining future service delivery levels is discussed, as well as considering the question ofexternal provision of library services. Use of information on fixed and variable costs andassessing break-even levels of service provision is illustrated as a helpful guide to library survival.  相似文献   
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Trans-Pacific transport of enhanced ozone plumes has been mainly attributed to fossil fuel combustion in Asia in spring, but less attention has been paid to vegetation fires in Asia. Here we show that the El Niño-Southern Oscillation (ENSO)-modulated fires in Southeast Asia, rather than Asian fossil fuel plumes, dominate the interannual variability of springtime trans-Pacific transport of ozone across the entire North Pacific Ocean. During El Niño springs, the intensified fires from both the Indochinese Peninsula and Indonesia, together with large-scale circulation anomalies, result in enhanced ozone plumes that stretch over 15 000 km in both the lower-middle and upper troposphere. This enhancement is also observed in the in situ measurements of ozone concentration, with an almost 10% increase at Mauna Loa Observatory, Hawaii, a unique site to monitor the long-distance transport over the North Pacific. This study reports an unexpectedly strong influence of vegetation fires, linked with climate variability, on global tropospheric chemistry and proves once more how complex the interactions in the climate system are.  相似文献   
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By the fourth/tenth century, Egypt's Nile Delta had just two major Delta branches debouching directly into the Mediterranean – the Dumyā? (Damietta) and Rashīd (Rosetta). Navigational conditions at these branches’ mouths were treacherous because of a combination of currents, winds, wave-fields and shifting sandbanks. These conditions were a danger to shipping, and so had a formative effect on the navigational landscape of the Delta. Despite its remoteness from the Nile, Alexandria remained Egypt's chief Mediterranean port, but only because river connections were maintained that avoided the Rashīd mouth. In contrast, the port of Rashīd was relatively insignificant. Similar conditions at the Dumyā? mouth prompted navigators to adopt routes via Lake Tinnīs, modern Lake Manzala, which linked to the sea through its calmer sea mouths. This article brings together material from multiple disciplines to offer a new understanding of the navigational context of Egypt's medieval Mediterranean ports.  相似文献   
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This investigation utilized an integrative model of development for ethnic minority children and a process model of engagement to explore whether three dimensions of school engagement (behavioral, emotional, and cognitive) mediated relationships between school racial climate, academic performance, and educational aspirations. A total of 139 African American students were recruited from a high school in the southeastern United States. Findings revealed an indirect association between perceptions of racial fairness and academic achievement indicators through behavioral and cognitive engagement. Behavioral and cognitive engagement also mediated relationships between youths’ perceived peer discrimination and academic achievement indicators. No significant indirect associations between teacher discrimination and academic achievement through school engagement dimensions were found. Study limitations, future directions, and implications are discussed.  相似文献   
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