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971.
The potential for the injury or death of a child resulting from the tip-over of a piece of household furniture or a domestic appliance has not been previously well recognized. We reviewed nine accidental deaths of young children that resulted from avoidable residential hazards and/or lapses in supervision of the children by their caregivers. The offending household items included televisions, bedroom dressers, a kitchen stove, and a lounge chair. The causes of death were mechanical asphyxia, blunt trauma, and combined blunt head trauma and asphyxia. All of the deaths could have been prevented by appropriate anchoring of the piece of furniture and/or closer supervision of the child. A thorough multidisciplinary investigation is essential in establishing the cause and manner of death in such cases and in identifying risk factors that may aid in the prevention of future childhood deaths.  相似文献   
972.
The high prevalence of alprazolam abuse translates to an increased workload for crime laboratories in characterizing seized tablets. These tablets may originate as diverted pharmaceuticals or counterfeited mimics, so efficient analytical techniques should provide confirmatory data while minimizing destruction of evidence. We offer the first report of a validated forensic method for confirming alprazolam tablets by direct analysis in real time-time of flight (DART-TOF) mass spectrometric analysis. This technique provides rapid identification of target analytes with minimal sample preparation, allowing direct analysis in the atmospheric sample gap. Selectivity is achieved through high resolution and mass accuracy, unique ion fragments, and chlorine isotopic ratios. This method utilizes fragmentation in two separate voltage functions to observe the alprazolam pseudo molecular ion at 309.09070 using 40 V and major ion fragments of 281.07197 and 205.07657 at 120 V. These parameters allow our laboratory to confirm alprazolam tablets efficiently, without compromising quality forensic standards.  相似文献   
973.
This study investigates whether a writer's gender can be determined from an inspection of simulated signatures written in the Arabic alphabet or Arabic abjad. It is generally believed that the penmanship of female writers is superior to male writers. There is also reason to expect that superiority in writing skill might contribute to success in simulating the signatures of other writers. Simulated signatures produced by a large population of male (414) and female (312) Arabic writers were graded, and the results were statistically analyzed. Women were found to have a marginal advantage simulating all elements of the signatures, but there was no statistically significant difference between the genders on any of the elements examined.  相似文献   
974.
Abstract: Secondary dentine is responsible for a decrease in the volume of the dental pulp cavity with aging. The aim of this study is to evaluate a human dental age estimation method based on the ratio between the volume of the pulp and the volume of its corresponding tooth, calculated on clinically taken cone beam computed tomography (CBCT) images from monoradicular teeth. On the 3D images of 111 clinically obtained CBCT images (Scanora®3D dental cone beam unit) of 57 female and 54 male patients ranging in age between 10 and 65 years, the pulp–tooth volume ratio of 64 incisors, 32 canines, and 15 premolars was calculated with Simplant® Pro software. A linear regression model was fit with age as dependent variable and ratio as predictor, allowing for interactions of specific gender or tooth type. The obtained pulp–tooth volume ratios were the strongest related to age on incisors.  相似文献   
975.
The analysis of gamma-hydroxybutyric acid (GHB) is problematic because it is hygroscopic, it lacks a good UV chromophore, and it undergoes heat-induced cyclization. This paper presents a new method utilizing ion-exchange chromatography (IC) with conductivity detection. The simple sample preparation, rapid analysis time, and inorganic anion detection capabilities are all advantages over the current methods. The detection of inorganic salts (formed during GHB synthesis) gives insight into the synthetic route utilized and can aid in drug seizure comparison. The developed method has a detection limit for GHB anions of 0.57 mg/L and chloride of 0.22 mg/L. A comparison of this technique with a current gas chromatography-mass spectrometry technique is presented, and a t-test found that the two methods' results are not statistically different at the 99.9% confidence level demonstrating the merits of this fast, simple, and informative IC method as a routine screening tool.  相似文献   
976.
Canines are usually used in anthropological and forensic sciences for sex and age determination. The best methods to estimate age are based on secondary dentine apposition, evaluated from periapical X-rays. The aim of this study was to propose a new method of sex and age estimation using 3D models to obtain more precise predictions using tooth volumes. Fifty-eight dental CT scans of patients aged 14-74 with a well-balanced sex ratio composed the sample. One hundred and thirty-three healthy canines were modeled (Mimics 12.0). The sample was divided into a training sample and a validation sample. An age formula was determined using the "pulp volume/tooth volume" ratio. Sex prediction was adjusted with total volumes. Applying the equations to the validation sample, no significant difference was found between the real and predicted ages, and 100% of the sex predictions were correct. This preliminary study gives interesting results, and this method is worth being tested on a larger data sample.  相似文献   
977.
Laser detection of latent fingerprints on a white paper has been performed, previously. Ultraviolet fluorescence from various kinds of printer toner and ink used for home printers were measured to study fluorescence imaging of fingerprints on a color-printed white paper. The experimental system consisted of a nanosecond pulsed tunable laser and a cooled CCD camera. Excitation wavelengths are 230 and 280 nm. Fourteen printers consisting of three color laser printers, three color inkjet printers, five monochrome laser printers, two monochrome copy machines, and a color copy machine were tested. Toner and ink of most printers exhibited fluorescence in the region from 360 to 550 nm. In most cases, clear fluorescence images were obtained by time-resolved imaging with a band-pass filter and 280-nm excitation. However for toners from laser color printers that showed strong fluorescence, better results were obtained with 230-nm excitation. Latent fingerprints on a photograph page and a black-character page of a newspaper were also imaged.  相似文献   
978.
以南京市城乡若干社区的实证调查为研究个案,深入探讨居民对街道办(乡镇)政府的信任度对居民参与社区志愿服务的意愿与居民的社区志愿精神究竟有何种程度的影响。通过Logistic回归分析,研究结果发现居民对街道办(乡镇)政府的信任度与居民的社区志愿精神之间存在着密切的关联性。对于各级政府而言,本研究的政策含义是需要特别关注影响居民对街道办(乡镇)政府信任的各种居民背景因素,培育居民对街道办(乡镇)政府的信任感和亲切感,不断促进居民社区志愿精神的孕育与成长,从而凝聚成社区草根民主成长的动力和纽带。  相似文献   
979.
目的采用分子印迹固相萃取,UPLC/MS分析,检验血液中大隆和溴敌隆。方法以大隆为模板分子,丙烯酰胺为单体,二甲基亚砜为有机溶剂,按照模板分子与单体摩尔配比关系为1∶4合成大隆分子印迹聚合物,作为固相萃取剂萃取血液中大隆和溴敌隆,以2×1mL去离子水、1mL 30%甲醇去离子水洗涤杂质,2×1mL 1%甲酸/甲醇洗脱,提取血中目标物后进行UPLC/MS分析检测。结果溴敌隆和大隆回收率均在90%以上,在50~500ng/mL浓度范围内线性关系良好r,2溴敌隆为0.998 4,大隆为0.991,检测限(S/N=5/1)低于10ng/mL。结论本方法回收率高,基质效应降低,杂质干扰少,可用于血液中低浓度大隆和溴敌隆的检验。  相似文献   
980.
目的建立分子印迹固相萃取(MISPE)、GC/MS分析方法,用于血液中苯丙胺类毒品检测。方法 10mmol/L醋酸铵缓冲液(pH8.0)4倍稀释空白添加血液,1mL甲醇,1mL10mmol/L醋酸铵缓冲液(pH8.0)活化苯丙胺类分子印迹固相萃取柱;2×1mL去离子水、1mL60%的乙腈去离子水、1mL1%醋酸乙腈洗涤杂质;2×1mL1%甲酸/甲醇洗脱,洗脱液挥干定容,经GC/NPD、GC/MS分析检测。结果各种苯丙胺类毒品回收率均在90%以上,在20~5 000ng/mL浓度范围内线性关系良好,r2为0.995 7~0.998 9,LOQ在16~30ng/mL之间,LOD在8~15ng/mL之间。结论本方法回收率高,净化效果显著,稳定性好,杂质干扰少,可用于血液中低浓度苯丙胺类毒品的分析检测。  相似文献   
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