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1.
Illicit heroin is rarely pure and may contain a number of other substances. The total particle size distribution in six illicit heroin preparations was analysed using a Malvern 2600 Particle Analyser and by sieving. The pattern of heroin distribution amongst these particles was determined by HPLC. The results show that a representative illicit heroin particle is approximately 45 μm in diameter (137 pmol heroin) and that particles occur over a wide size range, from at least 5.8 to 564 μm in diameter. Aggregated data for the samples studied showed that the overall distribution of heroin particle size largely follows the total particle size distribution, but that this correlation is not necessarily true for individual drug preparations. These results have important implications for any system designed to detect concealed illicit heroin preparations by collection and analysis of drug particles.  相似文献   

2.
Parity indicators in human skeletal material are highly desirable yet elusive. In this study, the relationships of dorsal pits and pubic tubercle elongation to parity are investigated in a sample of 148 modern female sets of pubic bones with associated birth information. The elongation of the pubic tubercle shows no significant correlation with number of births, but instead is associated with the distance this feature is from the pubic symphysis (p < 0.01) and the size of the arcuate angle (p < 0.05). Dorsal pits show a strong association with increasing numbers of births (p < 0.01), especially in younger women. However, in women over 50 years old, dorsal pitting is correlated with BMI (p < 0.05) and is not significantly correlated with number of births. While this study lends support to the correlation of dorsal pitting and parity, it currently does not reach the level of accuracy needed for forensic applications at the level of the individual.  相似文献   

3.
Histochemical successions of the gastric mucosa reaction are described, their role and the impact of the kallikrein-kinin system are evaluated, and pathophysiological aspects of development of Vishnevsky's spots as a pathognomonic sign of death from excessive cooling are described. Analysis of 34 deaths from excessive cooling helped determine the correlation between the size, volume, and depth of the gastric mucosa involvement, on the one hand, and duration of periods of cooling and freezing, on the other. The technique of expert evaluation of Vishnevsky's spots is described.  相似文献   

4.
目的用原位脱氧糖核苷酸末端转移酶介导的缺口末端标记法(TUNEL)观察大鼠死后心肌细胞DNA断裂与死亡时间(postmortem interval,PMI)的关系。方法建立SD大鼠死亡模型,在25.1℃,分别于死后6、12、24、36、48、60h提取大鼠心肌组织进行TUNEL检测,显微成像系统采集图像,经计算机图像系统分析及统计学处理。结果死后6~60h,心肌细胞核荧光染色依次由绿色、黄绿色亮度增强、亮黄色到荧光亮度减弱;形态由扁圆形或柱状,大小较均匀,到体积增大、呈毛虫状、多数核碎裂到形态不规整,大部分核形成碎片;心肌组织细胞核的IG,死后6h至36h依次增高,36h达到高峰,随后下降;心肌细胞核DNA的AG死后24h最高。结论死后各时间点,心肌细胞核的荧光颜色和亮度以及细胞核的大小和形态有一定的变化规律。  相似文献   

5.
The purpose of this article is to report findings concerning the relationship between poverty, inequality, and the homicide rate for a sample of 204 SMSAs. A measure of family income inequality exhibits a moderate zero order correlation with the homicide rate, but the effect becomes insignificant in the regression analysis. A second economic measure, that of the size of the poverty population, also exhibits a moderate zero order correlation with the homicide rate, but the partial effect is significant and the sign is quite unexpectedly negative. Additional unexpected results include strong partial effects for measures of Southern regional and racial composition. These findings suggest the need for reconsideration of the role of economic and perhaps subcultural factors in the explanation of urban homicide.  相似文献   

6.
Forensic pathologists are commonly asked to evaluate injuries on the basis of photographs. Members of the National Association of Medical Examiners were asked to participate in an online survey in which they were presented with 68 patterned injuries of the skin and asked to make a diagnosis ranging from very general (e.g., “blunt” vs. “sharp”) to specific (e.g., “baton blow”). This was not the case. Consensus for general diagnosis averaged 0.77 and 0.72 for specific diagnosis. While there was a strong correlation between consensus and confidence in aggregate, individual correlations were poor. Consensus diagnosis was inversely correlated with age, and positively correlated with jurisdictional size, medical degree, and whether or not the respondent was actively performing autopsies as a job function. A subsequent survey is exploring possible reasons for lack of consensus in low‐consensus questions. The high correlation between confidence and consensus at the aggregate level and low correlation at the individual level may have implications for quality assurance protocols.  相似文献   

7.
高毅 《中国司法鉴定》2010,(4):23-25,28
目的研究不同鞋种的鞋印长度与赤足平面足迹长度的差值数据,为利用现场各类不同穿鞋足迹分析身高等人身特点提供科学依据,也为足迹定量化分析与检验奠定基础。方法针对犯罪现场中常见鞋种,选取不同的鞋号,采集对不同足长、身高的实验者正常行走所捺印的穿鞋样本与赤足样本,对穿鞋足迹鞋印长度与赤足足迹长度进行统计与计算。结果得出不同鞋种鞋印长度与赤足平面足迹长度的差值数据。结论应用现场穿鞋足迹分析身高等人身特点时,应针对不同的鞋种,减去相关系数,结合原有身高分析公式,综合分析身高。  相似文献   

8.
9.
We studied correlations between size of the face, different complexes of somatic signs and constitutional types according to the I.B. Galant's scheme basing on the materials of a complex anthropometric examination of 1153 Russian girls 16-21 years of age. We found a mean level of correlations (maximum 0.5 of the coefficient of canonic correlation) between the parameters of various morphological subsystems "face-body" The factorial analysis allowed us to obtain two integrative indices describing a total size and shape of the face. Statistical processing revealed a trend to macroprosopia in the groups from leptosomic to megalosomic constitutional types of girls from the Galant's scheme (p < 0.001). The athletic girls have more pronounced maxillofacial (visceral) part and a reduced size of the frontal face. For application in forensic-medical practice we present equations for individual estimation of the variant of a total size and shape of the face as well as female somatotype.  相似文献   

10.
Shoeprints left at the crime scene provide valuable information in criminal investigation due to the distinctive patterns in the sole. Those shoeprints are often incomplete and noisy. In this study, scale‐invariance feature transform is proposed and evaluated for recognition and retrieval of partial and noisy shoeprint images. The proposed method first constructs different scale spaces to detect local extrema in the underlying shoeprint images. Those local extrema are considered as useful key points in the image. Next, the features of those key points are extracted to represent their local patterns around key points. Then, the system computes the cross‐correlation between the query image and each shoeprint image in the database. Experimental results show that full‐size prints and prints from the toe area perform best among all shoeprints. Furthermore, this system also demonstrates its robustness against noise because there is a very slight difference in comparison between original shoeprints and noisy shoeprints.  相似文献   

11.
目的检测经长期福尔马林固定的组织降解情况,并比较组织中SNP与STR的检出率。方法本文对24例经福尔马林固定、-20℃保存5年的组织样本,采用Quantifiler?Trio DNA定量试剂盒检测样本DNA的降解系数及浓度,运用55-SNPs SNa Pshot复合分型体系和Power Plex?21试剂盒分别进行SNP与STR检测。结果大部分样本降解系数在1~8,发生不同程度的降解。与未降解样本相比,SNP分型完全一致,检出率为100%;其中8例样本STR分型存在33个等位基因丢失,降解系数均大于2.6,且75.8%的等位基因片段长度大于300bp。当样本检测出16个STR基因座时,似然率与54个SNP相当。当样本检出大于17个STR时,似然率大于54个SNP。STR基因座片段长度与等位基因检出率之间呈负相关。除2例样本降解系数较小却发生等位基因丢失外,其余样本降解系数与等位基因检出率之间呈负相关。结论经福尔马林长期固定的组织DNA易降解,检测SNP明显优于STR,但需要更多的SNP以提高个体识别能力。  相似文献   

12.
A wealth of research suggests a direct association between minority group size and government social control, such as arrest or imprisonment rates. Prior work in this vein, however, gives scant attention to (1) types of law that explicitly address intergroup conflict and (2) regional variation in the salience of minority group threat. At the same time, research on organizational responses to law indicates that institutional linkages to legal environments dictate policy innovation and compliance, yet the relevance of such linkages for law enforcement agencies is less clear. The present research investigates these themes by focusing on law enforcement responses to hate crime in the United States. Data from a sample of large municipal and county policing agencies and their degree of compliance with the federal Hate Crimes Statistics Act are analyzed. Main effects models show that compliance with federal hate crime law is less likely in places with larger black populations, an intriguing finding in light of extant work suggesting that both formal social control and race-based hate crime offending are typically more prevalent where more blacks reside. This effect of black population size on compliance with hate crime law, however, is contingent on region. A positive correlation in the Northeast contrasts with an inverse association in the South. The findings also suggest that organizational facets of law enforcement agencies, notably their engagement in community policing, are associated with compliance. The results elaborate and qualify group threat explanations of government social control and contribute to a burgeoning literature on the utility of organizational theory in the realm of law enforcement.  相似文献   

13.
目的观察不同体积的血滴以3种撞击速度垂直撞击3种不同介质形成的滴状血迹形态及大小,并探讨其相关性。方法将8种不同体积(14~115IxL)的抗凝猪m形成血滴,以3种不同的撞击速度(3.1~5.4m/s)分别垂直滴落于白纸、玻璃及釉面地砖上,观察形成血迹的形态特征,测量其直径,并采用SPSS13.0统计软件进行分析。结果在3种撞击速度条件下,在3种介质上形成的滴状血迹直径均随血滴体积的增加而增大,血迹直径与血滴体积存在较好的线性关系,可得出回归方程(回归模型R2〉0.85,P〈0.01);介质表面越粗糙,血迹直径越小;仅在自纸上发现血迹边缘有突起形成,且其数目随血滴体积的增加而增多。撞击速度及血滴体积存在较好的多重线性关系,可得出多重回归方程(回归模型R2〉0.90,P〈0.01)。结论垂直撞击形成的血迹形态及大小与血滴体积、撞击速度具有显著的相关性,可望用于推测出血源位置、受伤体位及出血部位载体。  相似文献   

14.
Brain, liver, rectal and environmental temperatures were continuously monitored under controlled conditions, in 117 forensic fatalities, for up to 60 h after death. Cases were studied either naked (63%) or covered with two blankets (37%). Bodies were classified into fat and thin groups. Statistical analysis and curve-fitting of the data yielded the average triple-exponential formulae for each body site and each body group. The effects of covering of the torso and body parameters such as weight, height, surface area and 'cooling size factor' (Z) on postmortem cooling are assessed and discussed. Results show that covering of the torso has a significant influence on the rate of postmortem cooling, however, there is no good correlation between the body variables and the cooling rate.  相似文献   

15.
A video can be manipulated using synthetic zooming without using the state-of-the-art video forgeries. Synthetic zooming is performed by upscaling individual frames of a video with varying scale factors followed by cropping them to the original frame size. These manipulated frames resemble genuine natural (optical) camera zoomed frames and hence may be misclassified as a pristine video by video forgery detection algorithms. Even if such a video is classified as forged, forensic investigators may ignore the results, believing it as part of an optical camera zooming activity. Hence, this can be used as an anti-forensic method which eliminates digital evidence. In this paper, we propose a method for differentiating optical camera zooming from synthetic zooming for video tampering detection. The features used for this method are pixel variance correlation and sensor pattern noise. Experimental results on a dataset containing 3200 videos show the effectiveness of the proposed method.  相似文献   

16.
犯罪认定是一个动态的价值判断过程,司法三段论是这一判断过程的逻辑体现,在寻找大前提、确定小前提以及大小前提涵摄判断的过程中,犯罪构成理论并不能发挥实际的作用,因为犯罪的认定与犯罪构成理论之间并不具有必然的关联性,采取何种犯罪论体系也不会影响犯罪认定的结果。犯罪构成理论只是针对刑法规定的犯罪成立条件进行理论解读和体系建构的结果,作为解释结论它被解释对象和解释主体的前见所决定,在解释对象即刑法规定不变的前提下,不同的犯罪构成理论体系只是不同解释主体从不同逻辑前提出发所作的不同解释选择。  相似文献   

17.
On the grounds of results of combined anthropometrical examination of 1108 Russian juveniles 17-21 years old the relationship between face dimensions and various complex of somatic characteristics and constitutional types from Shtefko-Ostrovsky scheme was studied. The medium-sized relationship (correlation coefficient less 0.6) between parameters of various morphological subsystems "face-body" was established. Two integrative indices describing general face size and shape were calculated with the method of factor analysis. The tendency to macroprosopy in the row from asthenoid to digestive constitutional type from Shtefko-Ostrovsky scheme (p < 0.001) was revealed with the help of various statistic methods. Estimating equations to determine individual variant of general face size and shape and male somatotype by V. V. Bunak and Shtefko-Ostrovsky schemes were done for practical use the received results.  相似文献   

18.
We examine the hypothesis that corruption in a country negatively influences the macroeconomy through an increase in the country-specific interest rate (interest rate shock). An empirical study estimated the contribution of the interest rate shocks to the variance in output growth at 5.1% in Mexico within the framework of stochastic growth models for small open economies. We replicate this study with the same dataset and investigate which parameters affect the contribution of the interest rate shocks to business cycles. Then, we estimate the same model for different emerging economies to investigate the relationship between the corruption level and macroeconomic contribution of the interest rate shocks. For this purpose, we use Transparency International’s Corruption Perceptions Index (CPI) to measure the corruption level. Finally, we investigate the correlation between the CPI and the estimated series of the interest rate shock. Our findings are as follows. First, the average size of the interest rate shocks is positively associated with the contribution of these shocks to the variability of output growth. Second, the average size of the interest rate shocks is also positively associated with the corruption level. Third, the estimated interest rate shock and the corruption level are positively correlated with each other. As we treat the corruption level as an exogenous variable in the model, these findings lead us to accept the hypothesis. The “Appendix” further clarifies a well-known hypothesis that the cycle is the trend in an emerging economy.  相似文献   

19.
Li QQ  Liu XQ  Chen XP 《法医学杂志》2011,27(2):91-3, 101
目的 通过研究不同程度视敏度障碍者模式翻转视诱发电位(pattern reversal visual evoked potentials,PRVEP)P100的特征,分析不同视角光刺激下与视敏度之间的相关性.方法 选用视敏度分别为0.2、0.4、0.6、0.8、1.0志愿者共100只眼,采用不同空间频率(8°到7.5'...  相似文献   

20.
Improvised explosive devices such as pipe bombs are prevalent due to the availability of materials and ease of construction. However, little is known about how these devices actually explode, as few attempts to characterize fragmentation patterns have been attempted. In this study, seven devices composed of various pipe materials (PVC, black steel, and galvanized steel) and two energetic fillers (Pyrodex and Alliant Red Dot) were initiated and the explosions captured using high‐speed videography. The video footage was used to calculate fragment velocities, which were represented as particle velocity vector maps. In addition, the fragments were weighed. The results demonstrate a correlation between the type of energetic filler and both the size and velocity of the fragments. Larger fragments were produced by Pyrodex filler indicating a less complete fragmentation, compared with smaller fragments produced by double‐base smokeless powder. Additionally, higher fragment velocities were seen with Alliant Red Dot filler.  相似文献   

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