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1.
The use of ortho- and para-phenylenediamine (OPD & PPD respectively) for the enhancement of fingerprints in blood has been investigated. Optimal pH conditions and H2O2 concentrations have been determined using UV/Vis spectroscopy. Both OPD and PPD are effective and less hazardous alternatives to the presently used 3,3'-diaminobenzidine (DAB) for the development of blood fingerprints, especially on porous surfaces. The orange color of OPD and the purple color of PPD offer alternative colors to the brown color of DAB and the light green color of ABTS for standing out against particular backgrounds. Both OPD and PPD can be used after ninhydrin treatment, but the reverse is not the case.  相似文献   

2.
化学显色法快速筛选饮料及尿液中γ-羟基丁酸和γ-丁内酯   总被引:1,自引:0,他引:1  
Zhang SY  Huang ZP 《法医学杂志》2006,22(6):424-427,F0004
目的建立化学显色法快速筛选饮料及尿液中γ-羟基丁酸(GHB)及其前体γ-丁内酯(GBL)的方法。方法在酸性条件下GHB转化为GBL,GBL和盐酸羟胺在碱性条件下生成γ-羟基丁酰羟胺,γ-羟基丁酰羟胺在酸性条件下和三氯化铁反应,生成紫红色的络合物。结果饮料中GHB最低检出浓度为0.5~2mg/mL,低于常见滥用质量浓度。该方法也可以用于尿液分析,最低检出质量浓度为0.5mg/mL。考察了常见有机溶剂和麻醉镇静药物的干扰。结论该方法简单、安全、快速,为临床和法庭科学实验室快速筛选GHB和GBL提供了便利。  相似文献   

3.
“Purple drank” is a label typically applied to mixtures of codeine cough syrup with soda, although it has also been applied to mixtures of over-the-counter cough syrups and alcohol. This novel drug formulation was first popularized in the Houston, Texas rap music scene in the 1990’s, and since then references to purple drank have become common in rap and hip-hop songs, but remained virtually absent in other musical genres. Prior research has found that musical preferences can have an influence on choice and frequency of drug use. The goal of the present study is to examine the relationship between musical preferences and experimentation with purple drank. Self-reported information about musical preferences, substance use, and demographic characteristics were collected from 2,349 students at a large university in the southeastern United States. An analysis of lifetime purple drank and other drug use by musical preferences reveals that those who prefer rap/hip-hop music and rock/alternative have the highest risk for reporting purple drank use. Further, this relationship far exceeds the associations between musical preferences and other drugs. Results from logistic regression analyses indicate males, other drug users, and those that prefer rap/hip-hop music have a significantly higher likelihood of using purple drank.  相似文献   

4.
Diquat can be extracted with 1-butanol from high pH solution in the presence of several moderate reductants. The red colored reduced compound of diquat in water turns to a purple compound in 1-butanol. The absorption of the purple compound is 0.105 at 383 nm and 0.119 at 520 nm in 1 microgram diquat/ml 1-butanol. The latter value is a little higher than that of the red compound at 495 nm in water. The purple compound is much more stable than the red compound in water. More than 80% of 10 ppm diquat added can be extracted from serum, blood, tissues, urine and some drinks. The extraction with 1-butanol is useful for concentration of diquat contained in large volume. The lower limit of detection is 0.1 microgram/ml 1-butanol. Paraquat is insoluble in 1-butanol under the same condition. Therefore, this method is applicable for the determination of diquat when paraquat is also contained in the solution.  相似文献   

5.
In forensic image processing, it is often important to be able to separate a feature from an interfering background or foreground, or to demonstrate colors within an image to be different from each other. In this study, a color deconvolution algorithm that could accomplish this task is described, and it is applied to color separation problems in document and fingerprint examination. Subtle color differences (sometimes invisible to the naked eye) are found to be sufficient, which is demonstrated successfully for several cases where color differences were shown to exist, or where colors were removed from the foreground or background. The software is available for free in the form of an Adobe Photoshop-compatible plug-in.  相似文献   

6.
The appearance of hard human tissue after thermal damage permits certain conclusions to be drawn with regard to fire parameters. In addition to morphological destruction, the change in color of dental tissues like enamel, dentine, and cement is also important. We studied teeth extracted from 330 human males and females under well-defined time and temperature conditions. Using the DIN and RAL color indexes, the color phenomenon was evaluated on the basis of the amount of glowing obtained when the teeth were heated. It is easiest to determine the color change in cement, as no calculus or hindering plaques are on the root surface. In addition to this, destruction of the tooth root takes place only during extreme combustion conditions. Determining the dentine color is more difficult and is possible only after the enamel splits. Also, the different dentine thicknesses hinders the observation of color. When the enamel was tested, it was found that the differences in color caused by high temperatures are unimportant. Moreover, the enamel burst into small particles. The effect we observed regarding the anthracite lustre using low temperatures was typical, and the best results were obtained in dental roots with eight color scales. All three dental hard tissues have in common that the variations in color appear regularly and successively according to ascending temperature or duration of time: natural dental color, black, brown, blue, grey, white, and pink. In these processes, the temperature and combustion time are inversely proportional to the velocity of color change. The literature is discussed that deals with temperature- and time-dependent color phenomena of dental hard tissues destroyed as a result of thermal damage.  相似文献   

7.
《Science & justice》2023,63(4):477-484
The Body Fluid Forum of the Association of Forensic Science Providers recognised concerns raised by forensic practitioners regarding the lack of data to inform on the incidence of significant AP (Acid Phosphatase) reactions from vaginal and oral samples, i.e. those which might be misinterpreted as indicating the presence of semen. This is particularly relevant in the light of appeal court rulings regarding the need for data to support evaluations. This paper presents collaborative data on the nature and incidence of AP reactions from vaginal and oral swabs provided by donors. The results demonstrate that caution is required with mid to strong purple AP reactions from direct testing of oral swabs and with mid purple reactions from vaginal swabs. The use of a Bayesian approach to assist with the provision of opinions regarding the presence of seminal fluid is highlighted.  相似文献   

8.
This article traces the repression of a signifying elements like color in the art of the late medieval period and coordinates it with the rise of text, sovereignty and legal order in the 16th century. It uses Deleuze’s notions of life and the virtual as a springboard for an analysis of the power of color in Giotto, Fra Angelico, Grunewald, Cranach and Holbein. It traces a trajectory from an art in the late Middle Ages that decodes and escapes judgment through a joyful use of color to a privileging of text (be it biblical or legal), repression of color and its reterritorialization in classical representation, a despotic regime of signs – seen quite literally in the portrait of the imperial and despotic monarch, Henry VIII. This trajectory in art is linked to an analogous movement: the imposition and extension of sovereignty and the legal system as well as the colonization of social life by law in the formative period of the nation state. The challenge is to create a world of technicolor, to actualize the color of living and the living of color. Without it, there is only law, in black and white.
Marty SlaughterEmail:
  相似文献   

9.
城市房屋外墙颜色是城市色彩的重要组成部分。中国法律至今没有对城市色彩或城市房屋外墙颜色做出任何专门规定。外墙颜色的管理维护不仅是一个物业管理问题,而且也是行政机关封城市公共形象统一规划的一个重大问题。城乡规划法实施以後,外墙的色彩专业规划应该尽快起步并顾及城市历史文化、区划功能以及公序良俗等因素。  相似文献   

10.
程序法定原则作为刑事诉讼法的首位原则、“帝王”原则,构成了现代程序法的基石, 其地位如同罪刑法定原则之于刑法典。从内容上分析,程序法定原则包括了形式(程序合法性)和实质(程序正当性)两项要件,由此产生了形式意义上的程序法定原则和实质意义上的程序法定原则。作为现代刑事诉讼程序的一种通论性和一般性原则,程序法定原则对于整个刑事诉讼程序具有统摄性,在刑事诉讼各个阶段都存在着程序法定的具细原则。我国刑事诉讼制度在立法和司法实践中存在的种种问题最后几乎都可以归结为“程序法定”原则的不彰、程序法定价值的不显。基于此,刑事诉讼法典的制定和运行,贯彻程序法定原则是当务之急。  相似文献   

11.
In 1979, Miller and Patel showed that a solution containing two diacetylene monomers, 2,4-hexadiyne-1,6-bis(phenylurethane) (HDDPU) and 2,4-hexadiyne-1,6-bis(p-chlorophenylurethane) (HDDCPU) could be used to develop latent fingermarks on a non-porous surface. In the current work, the same mixture (HDDPU:HDDCPU=10:1, in acetone solution) was used to develop fingermarks on a wide variety of surfaces, both non-porous and porous, including paper. An airbrush system was optimized for the application of the reagent solution. Once the solution evaporates on a surface, the monomers co-crystallize in different ways, depending upon a number of factors, including the surface residue. "Active" co-crystallization leads (with heat or radiation) to the formation of purple polymer, while "inactive" crystallization results in a non-polymerizable white deposit. Fingermark contrast was achieved as a result of active co-crystallization (giving purple polymer) in either the ridges or the furrows, depending upon the surface and other factors. A general observation (supported by spot tests with linseed oil, salt and amino acid solutions) was that on paper, oily materials are more likely to lead to the formation of the purple polymer, while the presence of water inhibits polymerization. However, these observations are not consistent across all other substrates. It is hypothesized that water disrupts hydrogen bonding between diacetylene molecules, and thus prevents the topochemical polymerization of the diacetylenes, which occurs in the solid state between favourably aligned monomers. An interesting observation was the development of fingermarks deposited on paper that had already been treated with the diacetylene reagent.  相似文献   

12.
In this study we explore the inference of identity of source using a two-dimensional feature vector. As an example, we study the use of the Bayesian framework for the estimation of the value of evidence of color measurements for identity of source of blue ballpoint pen inks. Univariate as well as bivariate analyses are carried out for color data that was acquired with a flatbed scanner. While this might not be the best method to discriminate inks, we will use it as an example to estimate what the value of the evidence is, however low or high it may be. It is hoped that this exercise is instructional, as a similar approach can readily be applied in other situations.  相似文献   

13.
Color separation is an image processing technique that has often been used in forensic applications to differentiate among variant colors and to remove unwanted image interference. This process can reveal important information such as covered text or fingerprints in forensic investigation procedures. However, several limitations prevent users from selecting the appropriate parameters pertaining to the desired and undesired colors. This study proposes the hybridization of an interactive differential evolution (IDE) and a color separation technique that no longer requires users to guess required control parameters. The IDE algorithm optimizes these parameters in an interactive manner by utilizing human visual judgment to uncover desired objects. A comprehensive experimental verification has been conducted on various sample test images, including heavily obscured texts, texts with subtle color variations, and fingerprint smudges. The advantage of IDE is apparent as it effectively optimizes the color separation parameters at a level indiscernible to the naked eyes.  相似文献   

14.
本文介绍了一种双重免疫酶标染色方法(单酶法)。其原理是过氧化也物酶遇DAB-CoCl2-H2O2显蓝黑色,遇DAB-H2O2显棕黄色,两种颜色对比鲜明。将此法应用于检测法医尸检材料心和脑中的有关抗原,效果良好。该法灵敏、简便、经济,且切片可长期保存,困而有一定的实用价值。  相似文献   

15.
将真印文扫描后用彩色喷墨打印机打印的方法伪造印章印文,目前有上升趋势。结合一宗具体案件,研究该种伪造印章印文方法的特点与鉴定要点,供同行参考。  相似文献   

16.
Three categories of skin from Hanford miniature swine were examined microscopically: normal, unfrozen skin; skin exposed to -75 degrees C air for 5 min, 6 h postinjury; and skin frozen postmortem. Frostbitten skin (antemortem freezing) was characterized grossly by a purple discoloration and microscopically by dilated, blood-filled, superficial capillaries. Other changes in the frostbitten skin were vacuolated epithelial cells and dermal edema. Unfrozen skin (controls) and skin frozen postmortem were more difficult to differentiate. However, the epidermis of the latter usually was compressed and more basophilic. We concluded that skin frozen antemortem could be separated from skin frozen postmortem by its intense hyperemia, characterized grossly as a purple discoloration and microscopically by engorged capillaries.  相似文献   

17.
We review eight different data sets in this paper for the purposes of assessing the possibility that reported color of hair can produce a systematic bias in the interpretation of hair assays. We review studies or data sets that include heroin and its metabolites, cocaine and its metabolites, MDMA and its analogs, and amphetamine and methamphetamine. The studies have utilized a variety of different degrees of color categorization, ranging from the simple dichotomy of brown and black, to a high of 12 categories. The mean number of categories reported approaches 6 (mean = 5.875). There are a total of 2791 data points in this analysis. We utilize two major statistical techniques for assessing significance; one-way analysis of variance, and Tukey's Honestly Significant Difference procedure. In circumstances were only dichotomous contrasts are possible, one-way analysis of variance is used. In contrasts involving three or more categorical groups, Tukey's procedure is used. In circumstances where the homogeneity of group variances is not sustained by the Levene statistic, we use the Tamahane procedure, allowing an assessment that assumes unequal variances. The analysis of this data fails to discern a significant color effect. We speculate that it may be that variance is large in many domains affecting analyte recovery from hair. In large groups these variations tend to regress towards a typical or mean value. Thus the data here show that while there are group or aggregate differences in these 'typical' values, they are not great when considered in relation to the within-group variations which exist for those values. It is our view that color may play a role in the accumulation of drugs in hair, however it is likely to account for only a very small part of the complex process of drug accumulation.  相似文献   

18.
During postmortem examination of the dental arches of carbonized victims, dental restorative materials may be found. The aim of this study was to evaluate the effect of heat source action on the color stability of composite resin (CR) and glass ionomer cement (GIC) restorations, to discriminate between them and compare with antemortem dental data. Sixty bovine teeth (30 CR and 30 GIC) were prepared (6 × 6 × 2 mm) and separated into groups (n = 10). The color readouts were taken by spectrophotometer, before and after heat action (100°C, 200°C, 300°C), in an oven for 15 min. There were color alterations for all coordinates (ΔE, ΔL*, Δa* eΔb*) for both materials. GIC presented greater change. The authors concluded that it is possible to distinguish between the materials by the color changes analyzed by instrumental method, helping victim identification.  相似文献   

19.
20.
古小说《异苑》校理献疑   总被引:1,自引:0,他引:1  
:《异苑》是南朝刘宋时期著名的志怪小说 ,含有不少口语成分 ,语言颇具时代特色 ,是中古汉语研究的重要文献。此书传本讹误甚多 ,由于文字理解的某些偏差 ,现有的校理成果尚未能尽如人意。本文着重从历史语言学的角度 ,探讨其中的疑误之处  相似文献   

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