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1.
运用光谱成像技术区分同色棉纤维   总被引:1,自引:0,他引:1  
目的研究同色棉纤维的检验方法。方法运用成像光谱法对红、蓝、黑3个颜色组的棉纤维进行区分。结果红色棉纤维的鉴别率为62.2%,蓝色棉纤维的鉴别率为77.8%,黑色棉纤维的鉴别率为69.6%。结论实验结果表明,光谱成像技术可以区分大部分同色棉纤维。拓宽了纤维检验的方法,解决了同色棉纤维的区分问题,该方法能够用于对微量同色棉纤维的快速鉴别。  相似文献   

2.
This work was inspired by a recent case of child abuse where the question of the age of the bruises on the body was raised. The first part of this paper reviews published work on bruises. It illustrates the paucity of work in this field and the absence of studies of the colour changes in bruises of human skin with time. The second part of this paper consists of our own study of the appearance of bruises. The aim was to identify the colour changes which occur in bruises and over what time-scale, in order to determine whether bruises can be aged by appearance. A total of 369 photographs were obtained of bruises aged less than 6 h and up to 21 days old, in 89 subjects aged 10-100 years. It was found that the development of a yellow colour was the most significant change (subjects aged less than 65, P less than 0.001; subjects aged greater than or equal to 65 years, P less than 0.001). The development of a yellow colour occurred significantly faster in subjects aged less than 65 years. (P less than 0.001). The appearance of a blue and purple/black colour was of lesser significance. The appearance of a red colour did not alter significantly with time. From this study it was only possible to conclude that a bruise with a yellow colour was more than 18 h old.  相似文献   

3.
Xu QW  Wu D  Hu W 《法医学杂志》2006,22(6):436-437
目的比较两种DNA提取法对不同色泽肋软骨的DNASTR分型结果的影响。方法利用Chelex-100法和酚-氯仿法,分别对30例不同色泽的腐败尸体肋软骨进行DNA提取,STR复合扩增,ABI3100型基因分析仪对扩增产物进行检测。结果用酚-氯仿法提取的30例腐败尸体肋软骨,均检测到全部STR基因座的等位基因型。用Chelex-100法提取的肋软骨中,22例(11例白色、8例淡黄色、3例黄色)检测出全部STR基因座的等位基因型;7例(3例黄色、4例黄褐色)检测出部分STR基因座的等位基因型;1例黑灰色的腐败尸体肋软骨,未检测出STR基因座的等位基因型。结论根据肋软骨的色泽,选择适宜的DNA提取方法。对于颜色较深的肋软骨,用酚-氯仿法进行DNA提取有助于提高其STR基因座的检出率。  相似文献   

4.
While reflective spectrophotometry is an established method for measuring macroscopic hair colour, it can be cumbersome to use on a large number of individuals and not all reflective spectrophotometry instruments are easily portable. This study investigates the use of digital photographs to measure hair colour and compares its use to reflective spectrophotometry. An understanding of the accuracy of colour determination by these methods is of relevance when undertaking specific investigations, such as those on the genetics of hair colour. Measurements of hair colour may also be of assistance in cases where a photograph is the only evidence of hair colour available (e.g. surveillance). Using the CIE L*a*b* colour space, the hair colour of 134 individuals of European ancestry was measured by both reflective spectrophotometry and by digital image analysis (in V++). A moderate correlation was found along all three colour axes, with Pearson correlation coefficients of 0.625, 0.593 and 0.513 for L*, a* and b* respectively (p-values = 0.000), with means being significantly overestimated by digital image analysis for all three colour components (by an average of 33.42, 3.38 and 8.00 for L*, a* and b* respectively). When using digital image data to group individuals into clusters previously determined by reflective spectrophotometric analysis using a discriminant analysis, individuals were classified into the correct clusters 85.8% of the time when there were two clusters. The percentage of cases correctly classified decreases as the number of clusters increases. It is concluded that, although more convenient, hair colour measurement from digital images has limited use in situations requiring accurate and consistent measurements.  相似文献   

5.
This work was inspired by a recent case of child abuse where the question of the age of the bruises on the body was raised. The first part of this paper reviews published work on bruises. It illustrates the paucity of work in this field and the absence of studies of the colour changes in bruises of human skin with time. The second part of this paper consists of our own study of the appearance of bruises. The aim was to identify the colour changes which occur in bruises and over what time-scale, in order to determine whether bruises can be aged by appearance. A total of 369 photographs were obtained of bruises aged <6 h and up to 21 days old, in 89 subjects aged 10–100 years. It was found that the development of a yellow colour was the most significant change (subjects aged <65, P < 0.001; subjects aged ≥65 years, P < 0.001). The development of a yellow colour occurred significantly faster in subjects aged < 65 years. (P < 0.001). The appearance of a blue and purple/black colour was of lesser significance. The appearance of a red colour did not alter significantly with time. From this study it was only possible to conclude that a bruise with a yellow colour was more than 18 h old.  相似文献   

6.
The colour of the human skull was determined from 124 fresh skull samples using the tristimulus colour measurement system "Micro Color" and listed as The Commission Internationale de l'Eclairage (CIE) L*a*b*-values. The skulls were found to be relatively light (L*=72.5), nearly colourless on the a*-axis (a*=-7.4), and slightly yellow (b*=16.4). No difference was found between the colours of the outer and the inner surfaces of the skulls. Including a small number (n=8) of skulls from diabetic patients in the study, we detected no colour difference between the samples from diabetics and non-diabetics. However, a hitherto unknown correlation between the subjects' age and the yellowness (b*-value) of the skull could be demonstrated.  相似文献   

7.
有关乡土文学理论的分歧,根本点不在于对乡土文学这一概念中的"乡土"内涵的不同理解,而在对"乡土文学"这一概念的整体性把握上.中国文学传统中有浓厚的乡土意识,但没有乡土文学的概念和理论.新文学初期,对于美国local colour小说理论如何与中国文论对接与转换,在茅盾与周作人之间初步形成了中国乡土文学发展的两个向度.这两个向度后来被鲁迅整合成相对完整的乡土文学理论,即寓乡土思念、民生关怀和乡土批判于一体的乡土文学观.  相似文献   

8.
Human eye colour variation is strongly associated with single nucleotide polymorphisms (SNPs) in the OCA2-HERC2 locus, especially rs12913832 that is found in an enhancer element of OCA2. In a previous study we found that 43 out of 166 individuals in a Norwegian population with the brown eye colour genotype HERC2 rs12913832:AA or AG, did not have the expected brown eye colour. To investigate if duplications or deletions in the OCA2-HERC2 locus could explain the blue eye colour in these individuals, we analysed massively parallel sequencing (MPS) data for copy number variations (CNVs) in the OCA2-HERC2 region. The ∼500 kb long OCA2-HERC2 locus was sequenced in 94 individuals with the rs12913832:AG and AA genotypes. Of these, 43 were observed to have blue eye colour and 51 were observed to have brown eye colour. CNVs were analysed using R and the R-package panelcn.MOPS - CNV detection tool for targeted NGS panel data. In rs12913832:AG individuals, CNVs in 32 regions were significantly associated with blue eye colour (Benjamini-Hochberg adjusted p-value ≤ 0.05). In rs12913832:AA individuals, CNVs in 14 regions were associated with blue eye colour using raw p-values (p ≤ 0.05). The functional effects of these CNVs on OCA2 expression are yet to be investigated. However, this study suggests that CNVs in the OCA2-HERC2 locus might explain why some of the rs12913832:AG and AA individuals have unexpectedly blue eyes.  相似文献   

9.
刘宁  裴雷 《刑事技术》2007,(4):29-32
目的探讨利用彩色打印图像上的半色调结构特征进行种类鉴别的方法。方法通过对上百种彩色打印设备输出的实验样本进行放大观察和形态学特征比较,详细描述了半色调结构特征。结果发现半色调结构特征反映打印设备硬件和软件方面的固有特征,具有特殊性和稳定性,综合其构成的各个方面可以作为彩色打印设备机种鉴别的一个重要依据。  相似文献   

10.
The aim of this study was to assess colour variations that occur in several types of textiles and their constituent fibres, resulting from the long-term influence of various laundry detergents. A 14-day experiment was conducted using blue, red and grey/black cotton, wool, acrylic and polyester textiles. The spectrophotometric measurement of colour changes in fabric samples and test solutions, as well as the microspectrophotometric analysis of colour changes in single fibres were described. An evaluation of the observed colour changes from a forensic fibre analysis expert's point of view, as well as that of an average user/consumer of the textiles and laundry detergents is also provided.  相似文献   

11.
Five simulated scenes of crime have been studied in which the soils adhering to shoes, car tyres and plant roots have been compared with multiple control samples using dry colour, ashed colour, pH, saccharide levels and particle size analysis. Colour and pH were found to be as reproducible under simulated scenes of crime conditions as for true duplicates from homogeneous soil, whereas the variation in saccharide levels was slightly greater than for true duplicates. The interpretational scheme developed for the silt and sand fractions of homogeneous soils was applied to the samples from each simulated scene of crime and every comparison was found to be similar at the 99% confidence limit.  相似文献   

12.
By means of the new method of Streifenlichttopometrie (SLT) it is possible to record the complete body surface of casualties in a practically photorealistic fashion, i.e. three-dimensionally and in colour. In comparison with the classic method of Photogrammetry Streifenlichttopometrie (SLT) is remarkably faster (10,000 points/s instead of 1 point/s) and in addition the colour of every point measured upon the corpse's surface is instantly recorded. Taking into consideration the resolution required and the qualities of the camera system the body surface is recorded in 'patches', i.e., areas of a defined extension (in the present case 500 mmx500 mmx200 mm) which are marked with a body fixed reference frame to grant the exact matching of the data after the recording process. Length, perimeter, square and volume of the body segments and injuries can be determined. Furthermore the natural colour of the wounds can be used for an immediate classification according to the intensity of the impact forces. In addition the 3-D coordinates of the body surface including the wounds can be transferred into an animated computer simulation for the reconstruction of the traumatic events.  相似文献   

13.
用化学显色法、红外光谱法(IR),以及色-质联用技术(GC/MS)分析具有强烈刺激性气味的毒剂希埃斯(CS),在缺少已知对照样的情况下,用以上方法,可做出准确的鉴定.  相似文献   

14.
Frequency figures of the fibre population on textile cinema seats were measured in Sydney, Australia, in winter. Sixteen seats were analysed from a very popular cinema complex, with 3025 fibres classified according to colour, generic class and fluorescence properties (100 grey-black cotton fibres only). The recovered fibres were mostly natural fibres (84%) with cotton the most common generic type (70%). On the contrary, man made fibres were relatively rare (15%) with rayon constituting the majority of these (51%). The most common colour/generic class combinations were grey-black cotton (33%) and blue cotton (30%) accounting for 63% of the total population. All other frequencies were below 5%, most below 1% using only the two properties of colour and generic class. Fluorescence properties were found to be very discriminating as far as grey-black cotton fibres were concerned. These features are considered and discussed and in particular, to emphasise the significance of fibres as evidence of contact.  相似文献   

15.
A population survey was carried out to analyse examples of the coloured fibre population that may be expected to exist in both front- and top-loading domestic washing machines during Spring, in Sydney, Australia. White cotton T-shirts were washed both individually, and with a normal household wash load, then taped to recover extraneous fibres transferred during the wash cycle. Twelve thousand one hundred and seventy-eight fibres were classified according to length, colour and generic class. Cotton fibres were most prevalent (69.4%), followed by man-made fibres (24.2%). The most common colour/generic class combinations were black/grey cotton (27%), blue cotton (20%) and red cotton (15.6%). Other combinations generally represented under 2% of the total fibre population. Two thirds (65.9%) of the recovered fibres were under 2 mm in length, the proportion of fibres decreasing with increasing fibre length. Variations in machine type did not affect the distribution of fibres with respect to fibre type, colour or length.  相似文献   

16.
In 2002 a population study of textile fibres in human hair was carried out using 26 volunteers in Cambridgeshire, UK. Over 12,000 fibres were recovered from a variety of hair lengths using low adhesive tape and classified according to colour, generic type and fibre length. The results of the study showed that the most common fibre colours were black/grey (48%), blue (29.1%) and red (12.7%), the least common being green, orange/brown and yellow which each accounted for less than 5% of the total. Natural fibres (mainly cotton) were predominant (72.3%) and man-made fibres were considerably less frequent. When colour and generic type were classified together, the most common combinations were black and blue cottons. The least common were the man-made fibre/colour combinations with the most frequent of these accounting for less than 7% of the sample. Fibre loads carried by long hair were found to be significantly less than that carried by short hair. The results of this study are in accordance with previous fibre population studies using other types of recipient surfaces and are likely to be influenced by factors such as seasonal and geographical variation.  相似文献   

17.
无碳复写纸的X射线衍射分析   总被引:1,自引:0,他引:1  
通过对无碳复写纸原纸和显色涂层的X射线衍射分析,达到对不同厂家无碳复写纸区分的目的.  相似文献   

18.
19.
The regulatory HERC2 SNP, rs12913832, is strongly associated with blue and brown eye colour. However, eye colour in heterozygous rs12913832 individuals is observed to vary greatly. Missense mutations in OCA2, such as rs1800407 and rs74653330, are associated with lighter eye colour in some but not all heterozygous rs12913832 individuals. Determining the physical linkage of these variants might help to further explain eye colour variation. So far, experimental haplotyping of these variants has been challenging because the genomic distance between them (∼ 135 kb) exceeds the fragment lengths produced by commonly used DNA isolation kits. The aim for this study was to explore novel methods for long distance haplotyping to assess associations between OCA2-HERC2 haplotypes and eye colour. DNA was isolated from frozen blood samples collected from Norwegians that are known to be heterozygous for both HERC2 rs12913832 and OCA2 SNPs, either rs1800407 (n = 23) or rs74653330 (n = 17), using the newly commercially available Monarch® HMW (heigh molecular weight) DNA Extraction Kit (New England BioLabsinc). We successfully isolated DNA fragments up to 210 kb, which were long enough to haplotype OCA2-HERC2 loci by droplet digital PCR (ddPCR). Three haplotypes were observed in the study population: rs12913832:A-rs1800407:T in 22/23 individuals, rs12913832:A-rs1800407:C in 1/23 individuals and rs12913832:A-rs74653330:T in 16/16 individuals. As expected, all individuals with the rs12913832:A-rs74653330:T haplotype had intermediate to blue eye colour. However, the rs12913832:A-rs1800407:T haplotype was observed in both blue and brown-eyed individuals, suggesting more research is needed.  相似文献   

20.
一种发现高锰酸钾涂改痕迹的化学检测方法   总被引:2,自引:0,他引:2  
目的通过检测文书可疑涂改处的化学成分,确定其涂改变造性质。方法无损复写取样方法,锰离子定性检验方法。结果可快速检测高锰酸钾涂改文书。  相似文献   

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