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971.
Stature estimation is one of the four attributes of the biological profile obtained from human skeletal remains. The length of the long bones has been consistently used to estimate stature from regression equations, but these may be useless when dealing with fresh or decomposed mutilated remains. Until recently, there was no consistent assessment of the reliability of measurements of the sternum for stature estimation. The purpose of this paper is to test previously developed regression formulae for stature based on measurements of the dry sternum and to assess the reliability of measurements of the fresh sternum in estimating stature. The formulae developed by Menezes et al. and Singh et al. were applied to a sample of 5 known stature skeletons from the identified human skeletal collection curated at the National Museum of Natural History, in Lisbon, Portugal. Testing of these formulae showed that estimated stature confidence intervals do not allow discrimination between individuals with similar stature. The length of the fresh sternum was measured on a sample of 45 male individuals autopsied at the National Institute of Legal Medicine - North Delegation (Porto, Portugal). Cadaver length was regressed on sternum length and a simple linear regression formula was obtained. The regression model provided a 95% confidence interval of 13.32 cm and a correlation coefficient of only 0.329. Compared to other studies, regression formulae based on the length of the sternum provided considerably larger standard errors than that based on long bone lengths. These results suggest that the length of the sternum has limited forensic value and relatively low reliability in estimating stature from mutilated human skeletal remains, either skeletonized or fresh. 相似文献
972.
Although three-dimensional (3D) coordinates for human intra-skeletal landmarks are among the most important data that anthropologists have to record in the field, little is known about the reliability of various measuring techniques. We compared the reliability of three techniques used for 3D measurement of human remain in the field: grid technique (GT), total station (TS), and MicroScribe (MS). We measured 365 field osteometric points on 12 skeletal sequences excavated at the Late Medieval/Early Modern churchyard in V?eruby, Czech Republic. We compared intra-observer, inter-observer, and inter-technique variation using mean difference (MD), mean absolute difference (MAD), standard deviation of difference (SDD), and limits of agreement (LA). All three measuring techniques can be used when accepted error ranges can be measured in centimeters. When a range of accepted error measurable in millimeters is needed, MS offers the best solution. TS can achieve the same reliability as does MS, but only when the laser beam is accurately pointed into the center of the prism. When the prism is not accurately oriented, TS produces unreliable data. TS is more sensitive to initialization than is MS. GT measures human skeleton with acceptable reliability for general purposes but insufficiently when highly accurate skeletal data are needed. We observed high inter-technique variation, indicating that just one technique should be used when spatial data from one individual are recorded. Subadults are measured with slightly lower error than are adults. The effect of maximum excavated skeletal length has little practical significance in field recording. When MS is not available, we offer practical suggestions that can help to increase reliability when measuring human skeleton in the field. 相似文献
973.
974.
The online sale of psychoactive substances, including hallucinogens, is becoming a serious problem in many countries. This paper presents and discusses the mass spectrometric, infrared spectroscopic and nuclear magnetic resonance spectroscopic data of 2,5-dimethoxy-4-nitro-β-phenethylamine (2C-N), which was identified in a powder sample seized by the authorities in 2011 in Poland. The molecular mass of 2C-N (226.0954amu) was confirmed in the LC/ESI-QTOFMS experiment. The molecular ion was also observed in the GC-EI/MS spectrum. A characteristic set of ions for the parent substance was found using both chromatographic methods, and when derivatization with trifuluoroacetic anhydride (TFAA) was applied. Two broad dominant bands at 1520cm(-1) and 1342/1322cm(-1), observed in the FTIR spectrum of 2C-N, originated from the nitro group. NMR spectroscopy helped unequivocal elucidation of the structure. The applied identification procedure proved to be a powerful tool to determine the structure of a new designer drug. 相似文献
975.
Analysis of the Effect of Cyclophosphamide and Methotrexate on Chrysomya megacephala (Diptera: Calliphoridae),
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Ana Letícia Trivia M.Sc. Carlos José de Carvalho Pinto Ph.D. 《Journal of forensic sciences》2018,63(5):1413-1418
Forensic entomotoxicology investigates the effects of chemical substances in the development of scavenger insects and the reflection on estimating the minimum postmortem interval (PMI). To evaluate the impact of the chemotherapeutic drugs cyclophosphamide (CF) and methotrexate (MTX) on the postembryonic development of Chrysomya megacephala, controlled experiments were performed by rearing the larvae on spiked minced beef with different concentrations of these drugs. The results indicated that CF significantly decreased their developmental rate up to 28 h but had no significant effect on larval and adult sizes, survival rate, and sex ratio, whereas MTX decreased larval and adult sizes, survival rate, and there was a deviation in the expected sex ratio toward females in MTX‐exposed larvae but had no significant impact on developmental rate. These negative interference factors should be considered in cases of suspected death of people that have undergone chemotherapy. 相似文献
976.
Bite Mark Analysis in Foodstuffs and Inanimate Objects and the Underlying Proofs for Validity and Judicial Acceptance
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Fernando Rivera‐Mendoza D.D.S. M.Sc. Stella Martín‐de‐las‐Heras B.D.S. M.D. Ph.D. Pablo Navarro‐Cáceres M.Sc. Gabriel M. Fonseca D.D.S. Ph.D. 《Journal of forensic sciences》2018,63(2):449-459
Even though one of the first bite mark cases was Doyle v. State in 1954 (a bitten cheese case), the research has focused on bite marks inflicted in human skin. As published Papers, Case Reports, or Technical Notes can constitute precedents which are relied upon in making the legal arguments and a considerable amount of case law exists in this area, we present a systematic review on bite mark analysis in foodstuffs and inanimate objects and their underlying proofs for validity and judicial acceptance according to Daubert rulings. Results showed that there is vulnerability in these procedures, and it is essential to demand for focus scrutiny on the known error rates when such evidence is presented in trials. These kinds of bite marks are well documented; however, there has been little research in this field knowing that the protocols of analysis and comparison are the responsibility of the forensic odontologists. 相似文献
977.
The trends and correlates of child and juvenile homicide rates in three developmental age groups (0-5, 6-11, and 12-17) during 1990–2013 in Mexico are examined by using vital statistical data. Homicide rates for adults and children were calculated yearly and the place where homicides occurred and the means used to commit homicide examined. Changes and continuities in homicide rates during 2002–2007 and 2008–2013 and their association with socio-economic, status of women, public security efforts, and firearm availability variables were studied. Homicide rates increased rapidly for adults and children in 2008 as did the rates in which a firearm was used. Rates for adults and children 0–5 years were particularly correlated. In some states, the youngest children’s rates increased by 75% or more than the rates for adults. High-increase states for younger children were closer to the U.S. border, were farther from abortion services, and had growing rates of female-headed households. 相似文献
978.
The article presents the final part of an Icelandic research project on parents and children of divorce, focusing on grown-up children’s experiences of equal time-sharing arrangements, ETSA, after their parents’ divorce. It consists of a quantitative analysis of firstly a nationally representative sample mapping the frequency and experience of 18–59 years old individuals of ETSA after parents’ divorce, and secondly a qualitative analysis of 16 long interviews with 16 children of divorce reflecting on their experiences. Both analyses indicate different experiences of this type of arrangement. The reality of the arrangement in practice is that parents chose the arrangement on the basis of their own preferences rather than a court imposing it or because the generally accepted core conditions for a positive outcome for children were in place. These negative experiences of ETSA are discussed in further detail and the need for law reform and service improvement is considered. 相似文献
979.
Carlos Martín-Alberca Héctor Carrascosa Itxaso San Román Luis Bartolomé Carmen García-Ruiz 《Science & justice》2018,58(1):7-16
Ignitable liquids such as fuels, alcohols and thinners can be used in criminal activities, for instance arsons. Forensic experts require to know their chemical compositions, as well as to understand how different modification effects could impact them, in order to detect, classify and identify them properly in fire debris. The acid alteration/acidification of ignitable liquids is a modification effect that sharply alters the chemical composition, for example, of gasoline and diesel fuel, interfering in the forensic analysis and result interpretation. However, to date there is little information about the consequences of this effect over other accelerants of interests. In this research paper, the alteration by sulfuric acid of several commercial thinners and other accelerants of potential use in arsons is studied in-depth. For that purpose, spectral (by ATR-FTIR) and chromatographic (by GC–MS) data were obtained from neat and acidified samples. Then, the spectral and chromatographic modifications of each studied ignitable liquid were discussed, proposing several chemical mechanisms that explain the new by-products produced and the gradual disappearance of the initial compounds. Hydrolysis, Fischer esterification and alkylation reactions are involved in the modification of esters, alcohols, ketones and aromatic compounds of the studied ignitable liquids. This information could be crucial for correctly identifying these accelerants. Additionally, an exploratory analysis revealed that some of the most altered ignitable liquid samples might be very similar with each other, which could have impact on casework. 相似文献
980.
Meritxell Pérez Ramírez María Sánchez López Andrea Giménez-Salinas Framis Manuel de Juan Espinosa 《Journal of Sexual Aggression》2018,24(2):225-239
We have analysed the information in 342 police reports of stranger sexual offences recorded in 2010. We have carried out a multiple correspondence analysis and a cluster analysis using modus operandi variables to identify differential profiles in these types of sexual offences. We have come up with three profiles of stranger sexual offences, which concur in the two techniques used. By analysing the personal variables of the offenders with such profiles, we have found differences in terms of the offender’s country of origin and age. We will discuss the consequences of these results on the police investigation of stranger sexual offences. 相似文献