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981.
The majority of microfluidic devices used as a platform for low‐cost, rapid DNA analysis are glass devices; however, microchip fabrication in glass is costly and laborious, enhancing the interest in polymeric substrates, such as poly (methyl methacrylate) (PMMA), as an inexpensive alternative. Here, we report amplification in PMMA polymerase chain reaction (PCR) microchips providing full short tandem repeat profiles (16 of 16 loci) in 30–40 min, with peak height ratios and stutter percentages that meet literature threshold requirements. In addition, partial profiles (15 of 16 loci) were generated using an ultrafast PCR method in 17.1 min, representing a ~10‐fold reduction in reaction time as compared to current amplification methods. Finally, a multichamber device was demonstrated to simultaneously amplify one positive, one negative, and five individual samples in 39 min. Although there were instances of loci dropout, this device represents a first step toward a microfluidic system capable of amplifying more than one sample simultaneously. 相似文献
982.
Tarini Fernando M.B. B.S. Calle Winskog M.D. Roger W. Byard M.D. 《Journal of forensic sciences》2013,58(4):1085-1087
A 51‐year‐old man was found dead face down and partially submerged in a bathtub alongside two hairdryers. The hairdryers had continued to work, as the victim had bypassed the electrical board of the house prior to dropping them into the water. This had resulted in death due to electrocution, with subsequent heating of the bath water causing marked putrefaction and softening of the immersed body parts. The back and feet, which were not submerged, were preserved. The degree of anterior decomposition was not in keeping with the postmortem interval; however, regional decomposition with sparing of the back and feet provided a clue at autopsy as to the sequence of events. Individuals with training in, or knowledge of, electrical circuitry are capable of modifying domestic wiring so that safety switches and/or fuses can be bypassed ensuring that electrical devices will continue to function even while under water. 相似文献
983.
Han Chul Lee Ph.D. Se‐Yong Kim M.S. Jong Yeol Kim M.S. Seung Hwan Lee Ph.D. 《Journal of forensic sciences》2013,58(4):989-992
Since the Korean criminal DNA database was launched in 2010, we have focused on establishing an automated DNA database profiling system that analyzes short tandem repeat loci in a high‐throughput and cost‐effective manner. We established a DNA database profiling system without DNA purification using a direct PCR buffer system. The quality of direct PCR procedures was compared with that of conventional PCR system under their respective optimized conditions. The results revealed not only perfect concordance but also an excellent PCR success rate, good electropherogram quality, and an optimal intra/inter‐loci peak height ratio. In particular, the proportion of DNA extraction required due to direct PCR failure could be minimized to <3%. In conclusion, the newly developed direct PCR system can be adopted for automated DNA database profiling systems to replace or supplement conventional PCR system in a time‐ and cost‐saving manner. 相似文献
984.
Dawasaz A.A. B.D.S. M.D.S. Ajit D. Dinkar B.D.S. M.D.S. 《Journal of forensic sciences》2013,58(6):1621-1627
The palatine rugae possess unique characteristics that could be used when it is difficult to identify a dead person according to fingerprints or dental records. They are permanent and unique to each person. The rugae are surrounded by cheeks, lips, tongue, and buccal pad of fat; hence, they remain protected in trauma, incineration, or mass disasters. Their pattern of orientation is formed by the 12th to 14th week of gestation and remains stable throughout life. In this study, dental casts of 120 patients were analyzed for individual rugae characteristics and strength and subsequent individual codes were given. No two individuals were having exactly matching rugae codes. Dimensions of rugae pattern, incisive papilla, and midpalatal raphe were also noted. Rugae were reevaluated after one year to check its stability, which showed no significant difference. The coding system followed can be adopted as a good and simple technique to achieve electronic transfer of the records of the palatal rugae. 相似文献
985.
Ritva Karinen M.Cs. Vigdis Vindenes M.D. Ph.D. Inge Morild M.D. Lene Johnsen B.A. Ilah Le Nygaard M.D. Asbjørg S. Christophersen Ph.D. 《Journal of forensic sciences》2013,58(5):1393-1396
Two deep frozen persons, a female and a male, were found dead in a car. There had been an explosive fire inside the car which had extinguished itself. On the floor inside the car were large pools of liquid which smelled of gasoline. The autopsy findings and routine toxicological analyses could not explain the cause of death. Carboxyhemoglobin levels in the blood samples were <10%. Analysis with a headspace gas chromatography revealed methyl tert‐butyl ether (MTBE) concentrations of 185 mg/L (female victim) and 115 mg/L (male victim) in peripheral blood. The urine MTBE concentrations were 150 mg/L and 256 mg/L, respectively. MTBE is a synthetic chemical which is added to gasoline as a fuel oxygenate. Gasoline poisoning is likely to be the cause of the death in these two cases, and MTBE can be a suitable marker of gasoline exposure, when other volatile components have vaporized. 相似文献
986.
Anja Sasso D.D.S. Ph.D. Stjepan Špalj D.D.S. Ph.D. Barbara Mady Maričić D.D.S. Ph.D. Antun Sasso M.D. Ph.D. Tomislav Ćabov D.D.S. Ph.D. Mario Legović D.D.S. Ph.D. 《Journal of forensic sciences》2013,58(3):673-677
The study evaluated secular trends in dental development during a period of 30 years, correlation between dental and chronological age in Istria and the littoral region of Croatia. The sample consisted of 1000 panoramic radiographs of children, aged 6–16 years (mean 10.0 ± 1.8), taken in the period 1977–1979 (N = 500; 243 females) and 2007–2009 (N = 500; 299 females). Dental age was assessed according to Demirjian's method. Correlation between chronological and dental age was linear, positive, high, and statistically significant in both periods and genders, ranging from 0.73 to 0.86. Dental age was underestimated when compared to chronological age by 1 year on average, more 30 years ago (?1.35 ± 1.17) than today (?0.63 ± 1.09), less for girls (?0.80 ± 1.22) than boys (?1.21 ± 1.10). A statistically significant positive secular trend in acceleration of dental development was present of 0.72 years during the 30‐year period and was more significant in girls than boys (0.83‐ and 0.51‐year acceleration). 相似文献
987.
Danielle M. Butzbach Ph.D. Peter C. Stockham B.Sc. Hilton J. Kobus Ph.D. D. Noel Sims B.Sc. Roger W. Byard M.D. Robert J. Lokan M.Sc. George Stewart Walker Ph.D. 《Journal of forensic sciences》2013,58(1):90-100
The stability of two benzisoxazole antipsychotics was determined in vitro in decomposing porcine blood inoculated with bacteria, utilizing a high‐performance liquid chromatography with ultraviolet and fluorescence detection method for drug quantitation. Stability experiments for risperidone and paliperidone were conducted at 7, 20 and 37°C for 4 days using sterile and bacterially inoculated porcine blood. The drugs were stable in sterile blood at each temperature and in inoculated blood at 7°C, but degraded significantly in inoculated blood at 20 and 37°C. Complete loss occurred within 2 days when incubated at 37°C. The benzisoxazole‐cleaved degradation products for both drugs were identified as 2‐hydroxybenzoyl‐risperidone and 2‐hydroxybenzoyl‐paliperidone utilizing liquid chromatography quadrupole‐time‐of‐flight mass spectrometry and accurate mass measurements. The degradation products have been found in postmortem case studies, including one case where risperidone and paliperidone were not detected, indicating complete conversion can occur in situ. 相似文献
988.
Carol G.S. Tan 《The Journal of legal history》2013,34(3):279-304
The British authorities in the leased territory of Weihaiwei were concerned that too many Chinese, particularly women, resorted to suicide. In response, they made it obligatory to report suicides, educated the public and the police on how to effect rescues, and appointed a medical assistant with special responsibility for suicide rescue work. In spite of being remarkably well informed of the social significance of suicide in China, government efforts to deal with the causes of suicide were limited. In particular, the government did little to alter the circumstances of women in the territory. They provided few opportunities for education and were reluctant to prohibit foot-binding or to discourage families from putting pressure on widows to remarry. The limited response of the government to the problem of suicide was consistent with its general administrative policy of effecting little change to the fabric of life in the Chinese villages. The fact that the magistrates, in their treatment of suicide, expressed a deference to Chinese law, was part and parcel of the same general policy of the British administration of Weihaiwei. 相似文献
989.
Diana M. Wright Ph.D. Maureen J. Bradley Ph.D. Andria Hobbs Mehltretter M.S. 《Journal of forensic sciences》2013,58(2):358-364
Comparative analyses of 50 single‐layer white architectural paints were conducted to determine the discrimination power using standard techniques and to provide a basis for assessing significance when paints with limited features are not discriminated. Utilizing Fourier transform infrared spectroscopy (FTIR), 68 undifferentiated pairs resulted, yielding a discrimination of 94.45%. Adding stereomicroscopy, scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS) and backscatter electron (BSE) imaging, and pyrolysis‐gas chromatography/mass spectrometry (Py‐GC/MS), the overall discrimination was 99.35%. The study included blind verification replicates, which resulted in the only pairs without indications of physical or chemical differences. The remaining groups of undifferentiated samples contained subtle differences by at least one technique, but were considered undifferentiated for the discrimination power evaluations. This study demonstrates a high degree of discrimination of single‐layer white architectural paints using methods of analysis often encountered in forensic science laboratories. 相似文献
990.
David M. Jenkins Jr. Ph.D. W. Bosseau Murray M.D. Mary J. Kennett Ph.D. D.V.M. Edward L. Hughes M.A. Jacob R. Werner V.M.D. 《Journal of forensic sciences》2013,58(3):684-692
This study investigated and evaluated the safety margins of the continuous long duration (up to 30 min) effect of the TASER X26 waveform, using a Sus scrofa model. Long duration continuous stimulus has not been evaluated on humans or human surrogates prior to this study. Swine were used as models due to similarities with humans in their skin and cardiovascular systems. Very long duration was used to determine both exposure dose and possible adverse physiological effects of dose. The trial began with an application of 10 min, and subsequent animals received increasing exposure time up to a survived maximum duration of 30 min. At the onset of this work, it was hypothesized that there would be a time limit after which most animals would not survive consistent with increased dose response. However, this hypothesis was not supported by the experimental results. All animals (10 of 10) survived up to 3 min. Seven of the 10 animals survived up to a 10‐min exposure and 3 of 5 animals with a 30‐min target exposure survived the full exposure. Surviving animals were recovered and observed for 24 h, with no postrecovery deaths. This suggests that swine (based on physiology) will not experience a fatal event when exposed to the TASER X26 for a continuous 3 min. Conclusions regarding longer duration (10–30 min) are not as certain due to the small sample sizes at these time intervals. 相似文献