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241.
The spontaneous conversion of γ-butyrolactone (GBL) to γ-hydroxybutyric acid (GHB) in seven different Swedish tap waters was investigated. The waters used in the study were selected to represent the diversity among Swedish tap waters as well as possible, which was enabled by principal component analysis (PCA) of a number of water quality parameters. GBL solutions (5, 25 and 50% v/v) were prepared in each of the tap waters and in deionized water and the formation of GHB was followed over time. The GHB quantifications were made using a CZE method, employing a carrier electrolyte consisting of 25mM benzoic acid, 54mM tris(hydroxymethyl)aminomethane (Tris) and 1.7mM tetradecyltrimethylammonium bromide (TTAB), which was developed as a part of the current study. Data evaluation showed that the formation of GHB was largely dependent on the type of tap water. For example, there was a negative correlation between the kinetics of the GHB formation and the alkalinity of the tap waters (r(2)=0.990). This could be explained by a faster decrease in pH in the waters with low buffering capacity (i.e. low alkalinity), which catalysed the hydrolysis of GBL. Equilibrium was reached after 40-250 days depending on the initial GBL concentration and the type of tap water. The level of the equilibrium appeared to be dependent on the initial GBL concentration and ranged from 26 to 37%. Gained knowledge on the levels of the GHB/GBL equilibrium and the kinetics of the formation of GHB in tap water solutions of GBL, including the influence of the tap water quality, may be useful information for casework with the GHB/GBL problem in focus.  相似文献   
242.
Age estimation of living individuals has become one of the big issues of forensic anthropology. The increase of children and adolescents with no valid proof of their chronological age is a legal concern to many countries, especially in situations of illegal immigration, sub adult delinquency and juvenile work. For this purpose, the use of radiological methods for evaluation of skeletal maturation is particularly useful. In this study we compare the two of the most common methods applied in age estimation by hand/wrist radiographs: the Radiographic Atlas of Skeletal Development of the Hand and Wrist made by Greulich and Pyle (GP), 1959,and the Sempé method developed for computer--Maturos 4.0 (MT) program. These methods were applied to a sample of 230 radiographs of the hand and wrist from Portuguese children and adolescents of known sex age and age, aged between 12 and 20 years, who performed medical examination at the University of Coimbra Hospitals during 2005. The methods achieved different performances, depending on the age group. Between 12 and 15 years the bone age with the MT program is closer to the chronological age, whereas in older ages the GP Atlas method is more trustworthy. At the ages with legal consequences in Portugal (16 and 18 years) the GP Atlas method is most accurate, namely to decide whether an individual is younger or older than 18 years. Around 16 years old, although there are doubts in relation to the accuracy of both methods, GP Atlas seems to perform better.  相似文献   
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Beginning in the late 1980s, many health insurers refused to cover high-dose chemotherapy with autologous bone marrow transplant (HDC/ABMT) for high-risk and metastatic breast cancer patients. Insurers denied coverage because there was no persuasive evidence of clinical effectiveness. In response, many women sued to compel coverage. After years of litigation and the expenditure of approximately $3 billion, randomized clinical trials (RCTs) showed that the procedure was no more effective and possibly more harmful than conventional therapy. To understand whether and how litigation contributed to the diffusion of the procedure, we conducted a series of case studies that examine the litigation tactics and strategies used by defense and plaintiffs' counsel. Despite the fact that HDC/ABMT lacked proven scientific effectiveness, insurance defense attorneys were unable to stop the procedure's diffusion. Plaintiffs' attorneys had a much easier and more sympathetic story to tell and were able to exploit vulnerabilities facing the defense.  相似文献   
246.
ABSTRACT: The incidence of rape has increased, especially in metropolitan areas, such as the city of São Paulo. In Brazil, studies about it have shown that the majority of this type of crime is committed by the relatives and persons close to the victim. This has made the crime more difficult to be denounced, as only 10% of the cases are reported to competent police authorities. Usually, cytological exams are carried out in sex crime investigations. The difficulty in showing the presence of spermatozoa is frequent, but it does not exclude the presence of male DNA. The absence of spermatozoa in material collected from rape victims can be due to several factors, including the fact that the agressor suffers from azoospermia. This condition can be the result of a successful vasectomy. As the majority of DNA in the ejaculation sample is from spermatozoa, there is much less DNA to be analyzed. This study presents the application of Y‐STRs (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, and DYS393) in DNA analysis of sperm samples from 105 vasectomized men. The study demonstrated a great variation in DNA concentration. DNA extraction and amplification was possible in all sperm samples even in the absence of spermatozoa. The same profile was observed, for each individual, from DNA extracted from blood, pre‐ and postvasectomy semen samples. The use of markers specific for Y chromosome in sex crime cases, especially in the absence of spermatozoa, is very important, mainly because in most situations there is a small quantity of the agressor's DNA in the medium and a large quantity of the victim's DNA.  相似文献   
247.
Autosomal STR typing alone seems to be no sufficient tool for resolving deficiency cases (e.g. cases of questioned paternity or half-sibships). Therefore, we investigated whether the additional analysis of RFLP single locus probes can improve the solution of such complicated kinship cases. We analyzed 207 children and men from 101 families using the AmpFlSTRIdentifiler multiplex PCR kit and three RFLP single locus probes. A comparison between each child and all unrelated men resulted in 11,023 man / child pairs. Less than three excluding STRs were found in 125 child / unrelated man pairs (1.13%). Additional analysis of RFLP results reduced the number of ambiguous cases to 35. Half-sibling pairs were simulated using STR results from 20 cases with high paternity probabilities (group 1) and relatively low paternity probabilities (group 2). Using a commercially available computer program we calculated probabilities for 778 half-sibling pairs. In 35 pairs (4.49%) half-sibling probabilities over 90.0% could be calculated. Additional investigation of RFLP single locus probes did not lead to a more reliable evaluation of these results. The combined investigation of autosomal STRs and RFLP single locus probes can satisfactorily solve deficient paternities but does not contribute to the solution of questioned half-sibships.  相似文献   
248.
The objective was to investigate color change and surface damage in dental resin composites exposed to high temperatures over different time intervals for comparative purposes. Samples were prepared using two resins - Z100(R) (R1) and Charisma (R2), heated at the following temperatures: 200 degrees C, 400 degrees C, 600 degrees C, 1000 degrees C, for 15, 30 and 45 min (n = 104 for each resin sample). Color (DeltaE) and brightness (DeltaL) changes were analyzed by spectrophotometry using the CIE Lab system and surface changes by Scanning Electron Microscopy (SEM). R1 showed more intense color changes after heat exposure than R2. DeltaL values were found to be the best parameter for evaluation of light and color change. A biphasic pattern after thermal exposure was detected, from dark brown to light white. SEM showed more intense alterations in R2 than in R1. These results indicate that the parameters observed in both resins are useful as a guide in forensic analyses.  相似文献   
249.
Lamendin et al. (J Forensic Sci 1992;37:1373) developed a general technique to estimate age of adults at death using two dental features: periodontosis and translucency of the tooth root. Prince and Ubelaker (J Forensic Sci 2002;47:107) modified this method, creating a formula for each sex and for different ancestries, and obtained more precise age estimations. In the present study, the validity of each method was tested in 45 males and 34 females of Spanish Caucasian origin, and a novel formula, based on Prince and Ubelaker method, was specifically developed for a population of mixed racial origin (mestizo) from Colombia, and findings obtained were again compared with those yielded by Lamendin adult dental aging technique. The Prince and Ubelaker method proved more accurate than the Lamendin technique in the Spanish Caucasian population, and our Prince and Ubelaker-based formula was also more accurate than the Lamendin et al. In both populations, the Lamendin method showed a higher mean error in estimations of the age of youngest and oldest individuals. These findings confirm the need to create specific formulas for each human group in order to obtain more accurate age estimates.  相似文献   
250.
The article seeks to provide a perspective of human trafficking as one of the fastest growing criminal activities of the last few years in the area of organised crime and one that affects human beings’ most basic rights. In the main, the response to the problem has been its criminal prosecution, but without tackling the issues of need that underlie this conduct and which the traffickers take advantage of to abuse, assail and exploit the people they traffic. In this context, the evolution of Spanish legislation in terms of the criminalisation of this problem has made it one of the most repressive, although there is no clear evidence of its effectiveness. This punishment, which covers a wide range of criminal conducts, has not however been accompanied by any policies to support and integrate the victims of trafficking, which has led to a large number of victims being subjected to slavery who, in the majority of cases, fall under the control of the trafficking networks again.  相似文献   
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