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81.
Radiocarbon analysis was conducted on dental enamel, cortical bone and trabecular bone from four human adults from Andean Peru with known birth dates and death dates, the latter all falling within the modern bomb-curve period. Radiocarbon results were compared with known tropospheric values from the southern hemisphere. The results demonstrate that dental enamel can provide useful information regarding birth dates in consideration of known formation times of the specific teeth examined if the radiocarbon values fall within the modern bomb-curve period. Trabecular bone radiocarbon values are closer to the tropospheric values at the date of death than are values from cortical bone reflecting relative differences in the rate of bone remodeling in those tissues. Age at death also represents an important factor.  相似文献   
82.
Bone marrow (BM) analysis is of forensic interest in postmortem toxicological investigation in case of limited, unavailable or unusable blood samples. However, it remains difficult to determine whether a drug BM concentration is therapeutic or represents overdose, due to the lack of studies on this alternative matrix. Given the variations in BM composition in the body, sample location was suggested to be a relevant factor in assessing BM concentration. The aim of the present study was to compare postmortem caffeine concentrations in various BM sample locations and secondly to consider the correlation between BM and blood concentrations. Six BM samples (right and left side: proximal and medial femur and 5th rib) and a blood sample were collected from 21 forensic autopsies. Gas chromatography coupled to tandem mass spectrometry was performed. Blood caffeine concentrations ranged from 60 to 7591ng/mL. Femoral and rib BM concentrations ranged from 51 to 6171ng/g and 66 to 7280ng/g, respectively. Blood concentrations were always higher than BM concentrations. As a good correlation was demonstrated between blood and rib BM and between blood and the average of the four femoral BM concentrations, blood caffeine concentrations could be correctly extrapolated from BM concentrations. BM caffeine concentration was found to depend on sample location. Rib BM caffeine concentrations appeared to be systematically greater than averaged femur values and concentrations were much more variable between the 4 femur BM samples than between the 2 ribs. From a practical point of view, for caffeine analysis, rib BM appeared more relevant than femoral BM, which requires multisampling to overcome the concentration variability problem.  相似文献   
83.
This article addresses the theoretical difficulty of justifying the use of penal coercion in circumstances of marked, unjustified social inequality. The intuitive belief behind the text is that in such a context—that of an indecent State—justifying penal coercion becomes very problematic, particularly when directed against the most disfavored members of society.  相似文献   
84.
New Italian legislation on driving under the influence of drugs considers oral fluid (OF) as a possible alternative drug testing matrix. On this basis, the present research was carried out to evaluate the applicability of four commercial on-site OF drug screening devices, namely DDS(?), Drugtest 5000(?), Drugwipe 5+(?) and RapidSTAT(?), in a real operative context. Preliminarily trained police officers tested randomly stopped drivers with two different kits side-by-side during roadside patrols. A central laboratory confirmed on-site kits' results by UHPLC-MS/MS analysis of the saliva specimen remaining after the screening analysis. 1025 drivers were submitted to the OF tests: 11.6% were positive for cocaine and metabolites, 11.1% for THC, 6% for amphetamines and amphetamine-type designer drugs and 2.3% for ketamine. The sensitivities of the kits were 81% (RapidSTAT(?)), 82% (DDS(?)), 90% (Drugwipe 5+(?)) and 97% (Drugtest 5000(?)) for cocaine and 38% (DDS(?)), 47% (Drugwipe 5+(?)), 72% (RapidSTAT(?)) and 92% (Drugtest 5000(?)) for THC. Drugtest 5000 was the only kit showing an acceptable sensitivity for on-site application. Only Drugtest 5000(?) and RapidSTAT(?) could be evaluated for amphetamines and methamphetamines: Drugtest 5000(?) showed a sensitivity of 100% in the case of amphetamines and 86% for methamphetamines, while RapidSTAT(?) 90% and 76% respectively. Nowadays, ketamine is not included in the target analytes of any on-site devices, but it was systematically included in the UHPLC-MS/MS confirmatory analysis. To ensure adequate reliability, MS confirmation of on-site OF screening tests is anyway always necessary, due to the presence of a significant number of false positive results even when using the commercial kit with the best performance.  相似文献   
85.
Abstract: The aim of this study was to compare the accuracy of three methods for age estimation in children: the measurements of open apices in tooth roots (T), the ratio between the total area of carpal bones and epiphyses of the ulna and radius (HW), and the combined method (THW). The sample consisted of 288 Caucasian Italian children (152 boys and 136 girls) aged between 5 and 15 years. Accuracy was determined as the difference between estimated age and chronological age, and accuracy was assessed by analyzing individuals’ orthopantomograms and hand‐wrist radiographs. Accuracies were 0.41 years for girls and 0.54 years for boys with the THW method; for the HW method, 1.00 years for girls and 0.92 years for boys; and for the T method, 0.62 years for girls and 0.71 years for boys. THW is the most accurate technique for age estimation in these children.  相似文献   
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This article emphasizes the key role of labor in shaping trends and patterns of pica change. The first section of the article argues that during the interwar period, continental Latin America experienced common trends in several areas, including a general upsurge in labor unrest, deepening conflicts among elites, the implementation of new modes of state regulation, and a disruption of prevailing trade arrangements within the world economy, all of which were accompanied by a brief but significant wave of democratization in the 1920s. Noting that these general trends were unevenly distributed through the region (particularly after the 1930s), the second section of the article proceeds to abstract four patterns of political arrangements (repressive dictatorships, party competition, corporatist nationalism, and unstable labor politics). The article uses two principal variables (the relative weight of the middle and working classes and the degree of cohesion/fragmentation among elites) to explain these patterns of political change. Overall, the article suggests that the relative strength of labor and subordinate groups was key to shifts away from repressive dictatorship, while the degree of convergence among elites was significant in shaping political outcomes, but not in promoting democratic outcomes. I would like to thank Professor Irving Louis Horowitz for useful comments on an earlier version of this article. Previous versions of this research were presented at a seminar of the Latin American Studies Center at Princeton University, and at an annual meeting of the Southern Labor Studies Conference, where I benefited from comments by panel participants.  相似文献   
89.
Evidence of exposure of a metal component to a small charge explosion can be detected by observing microstructural modifications; they may be present even if the piece does not show noticeable overall plastic deformations. Particularly, if an austenitic stainless steel (or another metal having a face-centered cubic structure and a low stacking fault energy) is exposed to an explosive shock wave, high-speed deformation induces primarily mechanical twinning, whereas, in nonexplosive events, a lower velocity plastic deformation first induces slip. The occurrence of mechanical twins can be detected even if the surface is damaged or oxidized in successive events. In the present research, optical metallography (OM) and scanning electron microscopy (SEM), and scanning tunneling microscopy (STM) were used to detect microstructural modifications caused on AISI 304Cu steel disks by small-charge explosions. Spherical charges of 54.5 or 109 g TNT equivalent mass were used at explosive-to-target distances from 6.5 to 81.5 cm, achieving peak pressures from 160 to 0.5 MPa. Explosions induced limited or no macro-deformation. Two alloy grain sizes were tested. Surface OM and SEM evidenced partial surface melting, zones with recrystallization phenomena, and intense mechanical twinning, which was also detected by STM and X-ray diffraction. In the samples' interior, only twins were seen, up to some distance from the explosion impinged surface and again, at the shortest charge-to-sample distances, in a thin layer around the reflecting surface. For forensic science locating purposes after explosions, the maximum charge-to-target distance at which the phenomena disappear was singled out for each charge or grain size and related to the critical resolved shear stress for twinning.  相似文献   
90.
Abstract The proportional arena has been designed as a buffer and corrective for the hard verdicts of the new Italian plurality system. However, the political impact of this arena is much deeper than its purely electoral role. It measures the loadings of single parties within coalitions and, subsequently, influences their interactions and bargaining tactics. The elections of April 1996 clearly show the effects of institutional learning by the different actors involved: voters, coalitions, candidates, etc. The analysis of electoral data shows the following main findings: (a) the remarkable equilibrium between left–wing and right–wing coalitions; (b) the gains made by the left thanks to its better ability to manage alliances with the centre and extreme left; (c) surprisingly little change in voter behaviour between 1994 and 1996, and most of what change there is deriving from vote nationalization. The main features of Italian electoral geography are also confirmed.  相似文献   
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