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71.
In the statistical interpretation of forensic glass evidence it is standard practice to make the assumption of homogeneity of the refractive index (RI) of the source glass, or of localized homogeneity. However, the work of Locke and Hayes showed that, for toughened windscreen glass, this assumption might not be true. This work is well cited, but there appears to have been little follow-on published research. Furthermore, the toughening process is something known to affect the refractive index, and is a process that float glass does not undergo. Float glass is a major component of casework in New Zealand and for that reason it would be interesting to know whether the findings of Locke and Hayes apply when dealing with float glass. In this paper we describe an experiment similar to that of Locke and Hayes, systematically examining the variation of RI in a pane of float window glass. It was found that, although there were no systematic differences in refractive index, there were observable differences across the pane.  相似文献   
72.
In the wake of the 1990 amendments to the Clean Air Act, localities across the United States initiated public information campaigns both to raise awareness of threats to air quality and to change behavior related to air pollution by recommending specific behavioral changes in the campaign messages. These campaigns are designed to reduce the health hazards associated with poor air quality and to avoid federal sanctions resulting from the failure to meet air quality standards. As in many other communities across the country, a coalition of government agencies and businesses initiated a public information campaign in the Atlanta metropolitan region to reduce certain targeted behaviors, mainly driving. A two‐stage model used to analyze data from a rolling sample survey shows that the centerpiece of the information campaign—air quality alerts—was effective in raising awareness and reducing driving in a segment of the population. When the overall information campaign was moderated by employers' participation in programs to improve air quality, drivers significantly reduced the number of miles they drove and the number of trips they took by car on days when air quality alerts were sounded. Public information campaigns can be successful in increasing awareness, but changing well‐established behaviors, such as driving, is likely to require institutional mediation to provide social contexts that support the behavioral change, as well. © 2003 by the Association for Public Policy Analysis and Management.  相似文献   
73.
On the one hand the following case demonstrates the problems of finding a dead body in the bathroom and on the other hand the importance of postmortem x-ray examinations. The corpse of an 65-year-old woman was discovered in her bath tub. At the body's feet there was a hair dryer. Investigations concerning murder were negative, circumstances appeared to be unsuspicious. That was why a postmortem examination was not performed. -4 years later murder had to be considered. After manual strangling the deceased and the hair dryer were layed into the bath tub. The corpse was exhumed and taken to a forensic autopsy. It was found that the hyoid bone and the superior horn of the thyroid cartilage were both fractured on the right. Damages caused by the preparation itself were excluded by using serial roentgenographs. These observations in combination with histological findings and the results of further investigations convincingly supported the suspicion of strangling by hand.  相似文献   
74.
In many countries it is left to the discretion of the court to accept or reject conclusions based on sampling procedures as applied to the total drug exhibit. As an alternative to this subjective approach, a statistical basis is presented using binomial and hypergeometric distributions to determine a lower limit for the proportion of units in a population which contains a drug, at a given confidence level. A method for calculating the total weight of a drug present in a population within a given confidence interval is also presented. In the event of no failures (all units sampled contain a drug), a sample size of six or seven units is generally sufficient to state that a proportion of at least 0.70 of the population contains a drug at a confidence level of at least 90%. When failures do occur in the sample, point estimation is used as the basis for selecting the appropriate sample size.  相似文献   
75.
76.
Much attention has been paid to the nature of parent-adolescent relationships, with a frequent conclusion being that it is a time of marked disagreement between parents and their adolescents. However, other literature suggests that this time is not inherently conflictual. The purpose of this study was to examine agreement and disagreement between mothers, fathers, and adolescents on specific issues. Then, adolescent adjustment was assessed, and the degree to which it was a function of congruence with parents was examined. A modified version of the Issues Checklist was used to measure intrafamily agreement; the Revised Behavior Problem Checklist and the Harter Scale of Child's Actual Competence were completed by adolescents' social studies teachers to assess adolescent functioning. Relative to their parents, adolescents reported that they should make more decisions alone, while both mothers and fathers reported that decisions should be made jointly among all family members. Only father-adolescent congruence was found consistently to be related to adolescent functioning. Possible explanations for the present results and relevant issues pertaining to family agreement are discussed.  相似文献   
77.
Dilutions of 100 serum samples of various GM phenotypes were dotted onto a nitrocellulose membrane. The serum dot-blots were detected with peroxidase-labeled anti-G3M T monoclonal antibody (anti-G3M T MAb). Up to a 1 : 256 dilution could be G3M T-typed correctly. By use of anti-G3M T MAb and peroxidase-labeled anti-mouse IgG or the biotin-avidin system instead of use of labeled anti-G3M T MAb, up to a 1 : 512 or 1 : 1024, respectively, dilution was typable. As with previous work with G3M G MAb, the dot immunobinding (DIB) method for G3M T typing was found very simple and practical.  相似文献   
78.
Editors Note: This commentary touches on an aspect of technology transfer to the Third World that often is neglected: Can the technology recipients afford to use it? Although the authors focus on the economics of shrimp production by subsistence farmers, affordability is one of the major concomitant issues of transfer from developed to developing countries.  相似文献   
79.
80.
HIV infection is now perceived as the end stage of a chronic disease that is spreading most rapidly among blacks and Hispanics. The politics of the HIV epidemic in the 1980s were dominated by four interacting factors: fear and fascination; who had the disease and to whom it seemed to be spreading; the endemic problems of United States social policy; and the impact on policy of advances in scientific knowledge. This paper analyzes the political history of each of these factors and describes the dominant policies of the federal government and the states regarding HIV in the areas of surveillance, prevention, research, and financing. Four uncertainties will have a profound influence on the future politics of the HIV epidemic: how the states and the federal government will address the general problems of paying for the care of people with chronic diseases and providing access to care for the uninsured and the underinsured; the number and distribution of the sexual behaviors that transmit infection with HIV and the effectiveness of policies to persuade people to modify these behaviors; precisely who uses addictive drugs and the effectiveness of measures to change their behavior; and the natural history of the virus.  相似文献   
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