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301.
Abstract: Since Broca’s time (1824–1880), ossification of the neurocranial sutures has been used as a characteristic of age. Current approaches include the visual macroscopic examination of ecto and endocranial sutures. The evaluation of the cross‐section of sutures usually necessitates the destruction of the neurocranium. In a nondestructive alternative approach that was tested within the context of the “Digital Forensic Osteology” project that ran in cooperation with the Virtopsy®‐Project, it emerged that the resolution of conventional multi‐slice computed tomography data sets was not high enough to image sutures. Thus for the experiments presented here, the eXplore Locus Ultra flat‐panel computed tomography scanner from GE Healthcare was used. Calottes were scanned during autopsy and then immediately returned to the corpse. So far, the skullcaps of 221 individuals have been scanned. The cross‐sections of 14 suture segments could be assessed for seven previously defined stages of ossification. In a converse step, the 14 highest and lowest age estimate values corresponding to the individual stages of suture closure found were estimated for each calotte. The obtained ranges narrowing down the age estimate were evaluated with statistics. A mean value of 43.31 years for the range of narrowed age estimates shows that this method can be a useful aid in estimating age. The results of intra‐ and inter‐observer tests showed good overall agreement between the findings of three observers. This method is suitable for a nondestructive age estimation and can be used for the entire calotte.  相似文献   
302.
Abstract: A procedure for automated bullet signature identification is described based on topography measurements using confocal microscopy and correlation calculation. Automated search and retrieval systems are widely used for comparison of firearms evidence. In this study, 48 bullets fired from six different barrel manufacturers are classified into different groups based on the width class characteristic for each land engraved area of the bullets. Then the cross‐correlation function is applied both for automatic selection of the effective correlation area, and for the extraction of a 2D bullet profile signature. Based on the cross‐correlation maximum values, a list of top ranking candidates against a ballistics signature database of bullets fired from the same model firearm is developed. The correlation results show a 9.3% higher accuracy rate compared with a currently used commercial system based on optical reflection. This suggests that correlation results can be improved using the sequence of methods described here.  相似文献   
303.
Abstract: An online forensic dental identification exercise was conducted involving 24 antemortem–postmortem (AM–PM) dental radiograph pairs from actual forensic identification cases. Images had been digitally cropped to remove coronal tooth structure and dental restorations. Volunteer forensic odontologists were passively recruited to compare the AM–PM dental radiographs online and conclude identification status using the guidelines for identification from the American Board of Forensic Odontology. The mean accuracy rate for identification was 86.0% (standard deviation 9.2%). The same radiograph pairs were compared using a digital imaging software algorithm, which generated a normalized coefficient of similarity for each pair. Twenty of the radiograph pairs generated a mean accuracy of 85.0%. Four of the pairs could not be used to generate a coefficient of similarity. Receiver operator curve and area under the curve statistical analysis confirmed good discrimination abilities of both methods (online exercise = 0.978; UT‐ID index = 0.923) and Spearman’s rank correlation coefficient analysis (0.683) indicated good correlation between the results of both methods. Computer‐aided dental identification allows for an objective comparison of AM–PM radiographs and can be a useful tool to support a forensic dental identification conclusion.  相似文献   
304.
Abstract: This study evaluates the use of polydimethylsiloxane polymer composites (PDMS, Fe–PDMS) as a passive sampling media to preconcentrate analytes found in environmental settings. Samplers were made using commercially available silicone products. The composite samplers were assessed for their sorption properties using Atrazine and Irgarol 1051 as model compounds. The initial study assessed the utility of PDMS sheets as adsorption material by following analyte depletion from spiked water samples by solid‐phase microextraction gas chromatography/mass spectrometry (GC/MS). Follow‐up studies conducted at high and low concentrations using lab manufactured iron‐ PDMS rods (Fe–PDMS) showed effective uptake at differential rates from concentrations ranging between 1 μg/L and 10 μg/L. Adsorption mechanism was reversible, and compounds were recovered from the exposed materials and analyzed by liquid–liquid extraction‐GC/MS. Both composites showed better affinity for Irgarol 1051, 100% removal, than for Atrazine, 30% removal, likely representing their KOW differences, 3.6 and 2.6, respectively. This “proof of concept” study demonstrates the positive implications for the use of silicon polymer composites as a monitoring tool for environmental forensic purposes.  相似文献   
305.
Abstract: The University of Mississippi has a contract with the National Institute on Drug Abuse (NIDA) to carry out a variety of research activities dealing with cannabis, including the Potency Monitoring (PM) program, which provides analytical potency data on cannabis preparations confiscated in the United States. This report provides data on 46,211 samples seized and analyzed by gas chromatography‐flame ionization detection (GC‐FID) during 1993–2008. The data showed an upward trend in the mean Δ9‐tetrahydrocannabinol (Δ9‐THC) content of all confiscated cannabis preparations, which increased from 3.4% in 1993 to 8.8% in 2008. Hashish potencies did not increase consistently during this period; however, the mean yearly potency varied from 2.5–9.2% (1993–2003) to 12.0–29.3% (2004–2008). Hash oil potencies also varied considerably during this period (16.8 ± 16.3%). The increase in cannabis preparation potency is mainly due to the increase in the potency of nondomestic versus domestic samples.  相似文献   
306.
It has become apparent that marriage, while still strongly valued by society and government, has become less appealing to Americans as a whole. The changes taking place in society, whether economic or moral, have resulted in married couples becoming the minority in the United States. This decrease demonstrates that there is a need for reform, and that couples need to be provided with new options that will incentivize them to choose this union over cohabitation. This Note will discuss how expanding prenuptial agreements to allow couples to contract to the length of their marriage may help to accomplish that goal. This expansion will give couples the ability to tailor their relationship to fit their individual expectations and quell the reservations commonly associated with formalized relationships. Furthermore, such an expansion would be consistent with current law regulating premarital agreements and would still allow state governments to remain involved in regulation, making it less drastic of a reform than privatization.  相似文献   
307.
It is widely accepted that the number of self‐represented litigants has skyrocketed nationwide, especially in family law cases. Although nationwide comprehensive data on the number of self‐represented litigants do not exist, anecdotal evidence supports the belief that self‐representation is increasing. The challenge for courts and the entire legal profession is how to respond. Most observers in Indiana would agree that the traditional model of family law litigation—both spouses represented by lawyers settling their disputes before a judge—is no longer the norm in family law cases. Judges face a dilemma: assisting a self‐represented litigant to level the playing field against a represented party is seen by many as violating impartiality, even if the assistance is rendered to create a just result. In an effort to address the situation, the Indiana Supreme Court created the Pro Se Advisory Committee in April 2001. This article explores the long‐range implications of the issue of self‐represented litigants on Indiana's court system in hope that it will provide some insight for other jurisdictions. The first part of the article addresses the numbers of self‐represented litigants by tracking growth or declines in self‐represented cases and assessing whether there are any pockets of self‐represented litigants geographically or in certain case types. The second part of the article puts Indiana into context with the rest of the nation and reviews national trends. The third section reviews Indiana's response to self‐represented litigants over the last decade. The fourth section reviews current and ongoing projects in Indiana. The article concludes that the issue of self‐represented litigants will not fade away and that the challenge that guides the legal profession is how we provide equal access to justice for all who enter our courthouses.  相似文献   
308.
There are more than half a million children in foster care in the United States. Some of these children are adopted into loving families, but many are considered hard to adopt and never find a permanent family. Research suggests that the outlook for the teens who exit or age out of foster care without a permanent home or a meaningful adult relationship is bleak. They are more likely to face homelessness, joblessness, drug addiction, early pregnancy, mental health problems, and prison time. With such grim statistics, states should explore every possible permanent family resource for youth in foster care. This Note proposes that, in limited circumstances, it is in the best interest of the child to vacate a final order of termination and reinstate parental rights. It calls for states to adopt a model state statute based on the five state statutes currently in place that already allow for the reinstatement of parental rights.  相似文献   
309.
固相微萃取(SPME)可与GC/MS、HPLC/MS等在线联用,实现分离、分析一体化的特点为其在毛发药物分析中的应用提供了可能性和良好的应用前景。本文对SPME技术在毛发中滥用药物如苯丙胺类、美沙酮、大麻、可卡因、利多卡因等及其相应代谢产物的分析研究及应用进展做一综述。  相似文献   
310.
《国际相互影响》2012,38(4):345-368

This article presents the underlying rationale for a theory of foreign policy dynamics, and is the second part of a two‐part series which specifies a theoretical perspective for explaining the exchanges between nations. The task of the first paper was to discuss the substantive thrust of the research, and to give a view of the Monte Carlo simulation which lies at its core. The theory deals with the relevance of such concepts as reciprocity, uncertainty, third party effects, bureaucratic politics and domestic events for explaining foreign policy. This article provides the axioms which structure our theory and formal theorems that follow from these axioms.  相似文献   
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