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91.
This paper summarizes the results of previous work on the microscopic observation of linear dichroism found in dyed fibres (polyesters, polyamides, wool, silk, cotton, viscose, acrylics and acetates) and in pigmented fibres as well as the measurements on these fibre classes using microspectrophotometry with plane polarized light (MSP-PPL). The validation of this method is discussed and a practical tool is proposed for comparing fibre traces with control fibres. The limitations and strengths of this method are also revised. 相似文献
92.
Valeria Santoro Ph.D. Piercarlo Lozito D.D.S. Antonio De Donno Ph.D. Francesco Introna M.D. 《Journal of forensic sciences》2011,56(1):224-228
Abstract: This study was based on a morphometric analysis of bite marks starting from the quantitative definition of the anterior teeth by the geometric acquisition of the “injuries,” using bite marks impressed on pig skin and plastic. Each mark was photographed and acquired. A dedicated program automatically supplied the values of the shape factors and the areas of the pattern geometric figures. The values obtained for the homologous samples were compared to the heterologous values. Statistical comparison was made of the sets by linear regression, determining the correlation coefficient and the determination coefficient for each value. Results showed only 4.8% and 2% of overlap between homologous and heterologous values. This study was carried out in attempting to quantitatively define the anterior teeth of the human dentition and the procedure described and the results obtained support the advantage of morphometric studies and computer‐aided programs in this study of bite marks. 相似文献
93.
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Dr. Richard W. Boyd Paul R. Mencher Philip J. Paseltiner Ezra Paul Alexander S. Vajda 《Political Behavior》1988,10(3):197-213
This paper is an analysis of two rational choice theories of elections. Anthony Downs and Stanley Kelley's theories yield complementary interpretations of the 1984 U. S. election. Reagan's victory was based on both prospective and retrospective judgments as well as on candidate and policy considerations. Reagan won that element of an incumbent's reelection that is a referendum on his performance as president. However, people also voted on the basis of domestic and foreign policy preferences for the second term. On these issues voters preferred Mondale as much as Reagan. Reagan's victory owed remarkably little to his conservative agenda and to a warm regard for his personal qualities as a leader. His landslide was deceptive. The two Reagan victories were among the weakest of the six landslides of the postwar period by Kelley's test of decisiveness. The Reagan elections have not set the United States on the course of a long-term conservative agenda in either domestic or foreign affairs. 相似文献
95.
Melvin L. De Fleur 《Society》1988,25(2):72-81
His many publications include Theories of Mass Communication; Understanding Mass Communication; Milestones in Mass Communication Research;and, with Otto N. Larsen, The Flow of Information. 相似文献
96.
97.
Samyn N De Boeck G Wood M Lamers CT De Waard D Brookhuis KA Verstraete AG Riedel WJ 《Forensic science international》2002,128(1-2):90-97
In a double-blind placebo controlled study on psychomotor skills important for car driving (Study 1), a 75 mg dose of +/- 3,4-methylenedioxymethamphetamine (MDMA) was administered orally to 12 healthy volunteers who were known to be recreational MDMA-users. Toxicokinetic data were gathered by analysis of blood, urine, oral fluid and sweat wipes collected during the first 5h after administration. Resultant plasma concentrations varied from 21 to 295 ng/ml, with an average peak concentration of 178 ng/ml observed between 2 and 4h after administration. MDA concentrations never exceeded 20 ng/ml. Corresponding MDMA concentrations in oral fluid, as measured with a specific LC-MS/MS method (which required only 50 microl of oral fluid), generally exceeded those in plasma and peaked at an average concentration of 1215 ng/ml. A substantial intra- and inter-subject variability was observed with this matrix, and values ranged from 50 to 6982 ng/ml MDMA. Somewhat surprisingly, even 4-5h after ingestion, the MDMA levels in sweat only averaged 25 ng/wipe. In addition to this controlled study, data were collected from 19 MDMA-users who participated in a driving simulator study (Study 2), comparing sober non-drug conditions with MDMA-only and multiple drug use conditions. In this particular study, urine samples were used for general drug screening and oral fluid was collected as an alternative to blood sampling. Analysis of oral fluid samples by LC-MS/MS revealed an average MDMA/MDEA concentration of 1121 ng/ml in the MDMA-only condition, with large inter-subject variability. This was also the case in the multiple drug condition, where generally, significantly higher concentrations of MDMA, MDEA and/or amphetamine were detected in the oral fluid samples. Urine screening revealed the presence of combinations such as MDMA, MDEA, amph, cannabis, cocaine, LSD and psilocine in the multiple-drug condition. 相似文献
98.
99.
100.
Herbert Obinger Dr. 《Politische Vierteljahresschrift》2002,43(2):235-271
Starting from the stylised fact that federal institutions are held to be inimical to welfare state expansion, this paper examines the ways in which federalism has shaped the dynamics of welfare state development in Switzerland and Austria. A comparison of these different federal polities reveals that the welfare breaking effect attached to federalism crucially depends on the extent of vertical power separation. In both countries economic competition among constituent units did not fuel a race to the bottom in social standards. In Switzerland, the most important reason connected to federalism for why federal social policy was delayed and downsized was policy-preemption by the cantons and their considerable influence on the federal policymaking process. In contrast, the Austrian Länder neither had major social policy competencies nor an effective veto power which allowed them to block the centralisation of public policy. Instead, federalism is subordinate to the partisan arena at the central state level which itself is dominated by political parties quite favourable to welfare state expansion. 相似文献