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Ann L. Hollick 《Journal of policy analysis and management》1984,3(4):516-531
Long-range policy planning for international scientific and technological affairs has been hindered by a variety of problems. One is the overall crisis-response nature of foreign policymaking and another is the difficulty of developing technical information needed for sound forecasts. Within the State Department the record of attempts to establish systematic planning amply demonstrates the problems. Nevertheless, a number of key conclusions can be drawn from the few successful experiments in policy planning: An effective planning staff should combine the skills of both foreign policy specialists and scientists; planners should be closely familiar with, but not involved in, operations; the planning role requires consistent support from senior officials; the power to influence budgets significantly strengthens the planning function. 相似文献
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Yekkala R Meers C Van Schepdael A Hoogmartens J Lambrichts I Willems G 《Forensic science international》2006,159(Z1):S89-S94
The estimation of chronological age in cadavers, human remains and in living human beings by various methods is discussed. These methods, which are based on the age dependent non-enzymatic changes of l-form amino acids to d-form amino acids, mainly aspartic acid, are among the most reliable and accurate methods to date. Most of these methods use gas chromatography (GC). In this review, results of aspartic acid racemization in dentin at different targets are discussed. In addition, pre-considerations and guidelines are given for the selection of dentin from teeth. A pilot project was run to evaluate the efficiency of high performance liquid chromatography (HPLC) coupled with fluorescence detection. New buffer conditions were found to obtain stable derivatives of aspartic acid enantiomers for the estimation of racemization. 相似文献
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This paper presents an uncomplicated and minimally invasive method for age-at-death determination in a contemporary Dutch (West European) population, by modifying the approach of assessment based on the age-related remodeling of bone tissue. In contrast to the usual "osteon count," a "non-remodeled tissue count" is undertaken. To optimize the method, proper zeroing of the polarization filter set of the microscope is essential. Instructions for setting the filters are given. A sample of femoral shaft segments totaling 162 individuals with ages ranging from 15 to 96 years is analyzed. Subperiosteal quantitative assessments are recorded at the most anterior point of the femoral shaft and also at points 25 degrees to the left and to the right of that point. Interobserver agreement in the assessments shows an acceptable degree of correlation. Bone remodeling with age does not progress in a linear, but in a curvilinear manner. Dependence of predicted age on nonremodeled surface counts in the analyzed areas of the anterior cortex of the femur appears to be significant. A set of regression equations is given. Sex can be ignored in age prediction. The small but statistically significant dependence of predicted age on cadaver length corresponds with the present strong secular increase in stature in the Netherlands. A concise catalogue with micrograph examples for every 10-year period in life is available upon request. 相似文献
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