Preliminary study of hair form of Japanese head hairs using image analysis

The use of average curvature measurements for the forensic comparison of curly hairs has been reported, but a method, in which various types of hair form are quantitatively examined and objectively interpreted for hair comparison, has not been reported to date. In the present study, numerical data on hair form from Japanese subjects were obtained by image analysis and a morphological comparison of these head hairs was investigated. Head hairs obtained from eight Japanese males were measured for length (L), distance (D) and area (A) using a Kontron Imaging System KS400. From the three measurements mentioned above, three indexes, L/D, A/D and 2(A/L), were examined. The inter-individual variations for each value were investigated by a t-test and the availability of six values for the forensic comparison of hair form was evaluated by a stepwise linear discrimination analysis. Six values obtained from hair form by an image analysis showed large intra-individual variations. However, these six values were found to be useful for discriminating between two individuals, since the six values showed larger inter-individual variations than intra-individual variations. Discrimination on each comparison using a stepwise linear discrimination analysis was performed for some of the values and the results indicated conspicuous inter-individual variations between the two individuals. On 11 of 28 comparisons, 30 hairs from one individual could be completely distinguished from hairs of another individual, when a two-way comparison was employed. These results confirm that hair form could be quite useful in the forensic comparison of hair morphology, and suggest that numerical data obtained from hair form by image analysis are very important values for constructing a screening procedure for evidential hairs. The use of an objective measure of hair form will be especially useful for Japanese head hairs since they are generally thought to show very limited variation in morphological features.     

Mitochondrial DNA heteroplasmy among hairs from single individuals

A denaturing gradient gel electrophoresis (DGGE) assay was used to detect mitochondrial DNA (mtDNA) sequence heteroplasmy in 160 hairs from each of three individuals. The HV1 and HV2 heteroplasmic positions were then identified by sequencing. In several hairs, the heteroplasmic position was not evident by sequencing and dHPLC separation of the homoduplex/heteroduplex species was carried out with subsequent reamplification and sequencing to identify the site. The overall detection frequency of sequence heteroplasmy in these hairs was 5.8% (28/480) with DGGE and 4.4% (21/280) with sequencing. Sequence heteroplasmy of hair was observed even when the reference blood sample of the individual was homoplasmic. The heteroplasmic positions were not necessarily observed at sites where high rates of substitution have been reported. In two hairs, a complete single base change from the reference blood sample was observed with sequencing, while the heteroplasmic condition at that site in the hair was observed using DGGE. The DGGE results in such samples would serve as an aid in considering the possibility of match significance. In a forensic case, this situation would lead to the possibility of a failure to exclude rather than to be inconclusive.     

The applicability of holography in forensic identification: a fusion of the traditional optical technique and digital technique

In this study, the applicability of holography in the 3-dimensional recording of forensic objects such as skulls and mandibulae, and the accuracy of the reconstructed 3-D images, were examined. The virtual holographic image, which records the 3-dimensional data of the original object, is visually observed on the other side of the holographic plate, and reproduces the 3-dimensional shape of the object well. Another type of holographic image, the real image, is focused on a frosted glass screen, and cross-sectional images of the object can be observed. When measuring the distances between anatomical reference points using an image-processing software, the average deviations in the holographic images as compared to the actual objects were less than 0.1 mm. Therefore, holography could be useful as a 3-dimensional recording method of forensic objects. Two superimposition systems using holographic images were examined. In the 2D-3D system, the transparent virtual holographic image of an object is directly superimposed onto the digitized photograph of the same object on the LCD monitor. On the other hand, in the video system, the holographic image captured by the CCD camera is superimposed onto the digitized photographic image using a personal computer. We found that the discrepancy between the outlines of the superimposed holographic and photographic dental images using the video system was smaller than that using the 2D-3D system. Holography seemed to perform comparably to the computer graphic system; however, a fusion with the digital technique would expand the utility of holography in superimposition.     

Computer-assisted skull identification system using video superimposition

This system consists of two main units, namely a video superimposition system and a computer-assisted skull identification system. The video superimposition system is comprised of the following five parts: a skull-positioning box having a monochrome CCD camera, a photo-stand having a color CCD camera, a video image mixing device, a TV monitor and a videotape recorder. The computer-assisted skull identification system is composed of a host computer including our original application software, a film recorder and a color printer. After the determination of the orientation and size of the skull to those of the facial photograph using the video superimposition system, the skull and facial photograph images are digitized and stored within the computer, and then both digitized images are superimposed on the monitor. For the assessment of anatomical consistency between the digitized skull and face, the distance between the landmarks and the thickness of soft tissue of the anthropometrical points are semi-automatically measured on the monitor. The wipe images facilitates the comparison of positional relationships between the digitized skull and face. The software includes the polynomial functions and Fourier harmonic analysis for evaluating the match of the outline such as the forehead and mandibular line in both the digitized images.     

Passive forensics in image and video using noise features: A review

Due to present of enormous free image and video editing software on the Internet, tampering of digital images and videos have become very easy. Validating the integrity of images or videos and detecting any attempt of forgery without use of active forensic technique such as Digital Signature or Digital Watermark is a big challenge to researchers. Passive forensic techniques, unlike active techniques, do not need any preembeded information about the image or video. The proposed paper presents a comprehensive review of the recent developments in the field of digital image and video forensic using noise features. The previously existing methods of image and video forensics proved the importance of noises and encourage us for the study and perform extensive research in this field. Moreover, in this paper, forensic task cover mainly source identification and forgery detection in the image and video using noise features. Thus, various source identification and forgery detection methods using noise features are reviewed and compared in this paper for image and video. The overall objective of this paper is to give researchers a broad perspective on various aspects of image and video forensics using noise features. Conclusion part of this paper discusses about the importance of noise features and the challenges encountered by different image and video forensic method using noise features.     

Mitochondrial DNA amplification success rate as a function of hair morphology

This study examines the amplification success rate of mitochondrial DNA from human head hair with respect to their potential for forensic application. Mitochondrial DNA was isolated using a Chelex-based extraction method and amplified using the LINEAR ARRAY duplex PCR system. The particular focus of this study was to characterize the morphological features of human head hair in order to further the understanding of the factors that influence amplification success rate in hair tissue using the LINEAR ARRAY duplex PCR system. 2554 head hairs from 132 individuals representing four population groups were amplified. The hair samples were characterized as follows: 1251 were identified microscopically as telogen hairs and 1303 were classified as hairs without roots (removed before extraction). Amplification success was assessed as a function of several independent variables: morphological characteristics; telogen root versus no root; donor age; scalp origin; use of cosmetic hair treatments; and race of the donor. The results show that a positive correlation exists between amplification success and the presence of a telogen root. Combining the amplification success with either the original or optimized protocol, telogen hairs result in an overall success rate of 77.5% compared with 65% for hairs with no roots. Controlling for telogen hairs, the findings indicate that the overall success rate is independent of cosmetic hair treatments; medulla structure; shaft length, diameter, and volume; and scalp origin. Conversely, the age of the donor, the race of the donor, and hair pigmentation all contribute to a variation in amplification success rate.     

毛发常见机械性损伤形态的环境扫描电镜研究

目的建立环境扫描电镜(ESEM)法推断毛发致伤物种类的新方法。方法应用ESEM观察分析不同锐器、钝器及致伤方式形成的毛发机械性损伤的微观形态特征。结果毛发锐器、钝器损伤的表面微观特征存在显著差异,同种类型致伤工具,其锋利程度、作用方式不同时,其损伤特征也明显不同。结论ESEM法能够真实、自然反映毛发机械性损伤表面微观特征,可应用于推断毛发致伤物种类。     

Statistical comparison of dog and cat guard hairs using numerical morphology

Numerical features obtained from the guard hairs of dogs and cats (total 300 hairs per dog or cat) were statistically compared, in an attempt to discriminate between them. Using hairs from each of five mongrel dogs and cats, eight measurements (length (Len), maximum width (MaxWid), cross sectional maximum diameter, cross sectional minimum diameter, cuticular thickness of the cross section and three scale counts per 100 microm length (observed at three positions: distal third (disSC), middle (midSC) and the proximal third (proSC) portions) and five indexes (hair width index (HWI), medulla index (MI), hair index, cuticle index and the difference in scale counts between the distal and proximal parts (defSC)) were examined. The range for each numerical feature overlapped each other extensively, and none of the features permitted a discrimination between dog and cat hairs, based on the values obtained. However, 12 numerical features, except for the midSC, showed a statistically significant difference between dog and cat hairs, as evidenced by a t-test. For the purpose of comprehensively comparing numerical features and statistically discriminating between dog and cat hairs, a discriminant analysis between the two were carried out using a multiple regression analysis. Four types of discriminant functions produced by combining over five numerical features were examined. Dog and cat hairs could clearly be discriminated using any of the discriminant functions. Species discrimination using the discriminant function permitted the species of a dog or cat to be determined, based on the overall morphologies of various numerical features. When experimentally collected test samples were investigated using the discriminant function using Combination-2, consisting of eight numerical features (Len, MaxWid, MI, HWI, disSC, midSC, proSC and defSC), all 10 cat hairs were correctly determined to be cat hair and 22 of 23 dog hairs were correctly identified. This discriminant function produced good results for species discrimination between dog and cat hairs.     

毛发中毒品分析

毛发分析在法庭毒品分析领域有其独特的优势,很多国家的法化学实验室,毛发分析已成为毒品检测的常规操作,并已得到了法庭的承认、采纳。本文对毒品进入毛发的机制、毛发的现场勘查、毛发中毒品分析程序、毛发中毒品分析结果的评判进行了综述。简单地介绍了毛发在现场勘查中采取、包装、送检的基本方法和技术人员在操作过程中的注意事项,以及针对毛发检验中的特殊技术处理;另外,介绍了毛发中毒品分析的特点,通过分析毛发毒品的药理机制,总结出了一些高效、便利、快速的毒品分析方法,并对各种方法进行了介绍,得出了毛发中毒品分析结果的一些特点。     

On using gait in forensic biometrics

Given the continuing advances in gait biometrics, it appears prudent to investigate the translation of these techniques for forensic use. We address the question as to the confidence that might be given between any two such measurements. We use the locations of ankle, knee, and hip to derive a measure of the match between walking subjects in image sequences. The Instantaneous Posture Match algorithm, using Harr templates, kinematics, and anthropomorphic knowledge is used to determine their location. This is demonstrated using real CCTV recorded at Gatwick International Airport, laboratory images from the multiview CASIA-B data set, and an example of real scene of crime video. To access the measurement confidence, we study the mean intra- and inter-match scores as a function of database size. These measures converge to constant and separate values, indicating that the match measure derived from individual comparisons is considerably smaller than the average match measure from a population.     

Development of a Protein‐based Human Identification Capability from a Single Hair

Shed human hair (lacking root nuclear DNA) frequently contributes important information to forensic investigations involving human identification. Detection of genetic variation observed in amino acid sequences of hair proteins provides a new suite of identity markers that augment microscopic hair analysis and mitochondrial DNA sequencing. In this study, a new method that completely dissolves single hairs using a combination of heat, ultrasonication, and surfactants was developed. Dissolved proteins were digested and genetically variant peptide (GVP) profiles were obtained for single hairs (25 mm) via high‐resolution nanoflow liquid chromatography‐based mass spectrometry and a novel exome‐driven bioinformatic approach. Overall, 6519 unique peptides were identified and a total of 57 GVPs were confirmed. Random match probabilities ranged between 2.6 × 10^?2 and 6.0 × 10^?9. The new bioinformatic strategy and ability to analyze GVPs in forensically relevant samples sizes demonstrate applicability of this approach to distinguish individuals in forensic contexts.     

Microscopical discrimination of human head hairs sharing a mitochondrial haplogroup

In forensic analyses, determining the level of consensus among examiners for hair comparison conclusions and ancestry identifications is important for assessing the scientific validity of microscopical hair examinations. Here, we present data from an interlaboratory study on the accuracy of microscopical hair comparisons among a subset of experienced hair examiners currently analyzing hair in forensic laboratories across the United States. We examined how well microscopical analysis of hair can reliably be used to differentiate hair samples, many of which were macroscopically similar. Using cut hair samples, many sharing similar macroscopic and microscopic features, collected from individuals who share the same mitochondrial haplogroup as an indication of genetic relatedness, we tested multiple aspects that could impact hair comparisons. This research tested the extent to which morphological features related to ancestry and hair length influence conclusions. Microscopical hair examinations yielded accurate assessments of inclusion/exclusion relative to the reference samples among 85% of the pairwise comparisons. We found shorter hairs had reduced levels of accuracy and hairs from populations examiners were not familiar with may have impacted their ability to resolve features. The reliability of ancestry determinations is not yet clear, but we found indications that the existing categories are only somewhat related to current ethnic and genetic variation. Our results provide support for the continued utility of microscopical comparison of hairs within forensic laboratories and to advocate for a combined analytical approach using both microscopical analysis and mtDNA data on all forensic analyses of hair.     

脱落毛发及毛干DNA的STR分型研究

目的探讨脱落毛发及毛干细胞核DNA提取、含量和STR分型问题。方法对脱落毛发或毛干进行DNA提取和定量,使用低扩增体系、增加循环次数和多次平行扩增等方法扩增DNA样本,采用叠加比较的方法分析STR分型。结果15cm脱落毛发样品DNA含量大于0．3ng的样品占52．8％,STR分型成功率为55．6％;15cm毛干样品DNA含量大于0．3ng的样品占30．6％,STR分型成功率为25％。结论采用增加循环次数、多次平行扩增等LCN—STR分型方法和Mini—STR试剂盒有助于脱落毛发及毛千的STR基因座分型获得。     

Human hair histogenesis for the mitochondrial DNA forensic scientist.

Analysis of mitochondrial DNA (mtDNA) sequence from human hairs has proven to be a valuable complement to traditional hair comparison microscopy in forensic cases when nuclear DNA typing is not possible. However, while much is known about the specialties of hair biology and mtDNA sequence analysis, there has been little correlation of individual information. Hair microscopy and hair embryogenesis are subjects that are sometimes unfamiliar to the forensic DNA scientist. The continual growth and replacement of human hairs involves complex cellular transformation and regeneration events. In turn, the analysis of mtDNA sequence data can involve complex questions of interpretation (e.g., heteroplasmy and the sequence variation it may cause within an individual, or between related individuals. In this paper we review the details of hair developmental histology, including the migration of mitochondria in the growing hair, and the related interpretation issues regarding the analysis of mtDNA data in hair. Macroscopic and microscopic hair specimen classifications are provided as a possible guide to help forensic scientists better associate mtDNA sequence heteroplasmy data with the physical characteristics of a hair. These same hair specimen classifications may also be useful when evaluating the relative success in sequencing different types and/or forms of human hairs. The ultimate goal of this review is to bring the hair microscopist and forensic DNA scientist closer together, as the use of mtDNA sequence analysis continues to expand.     

一种AI换脸方法生成的伪造视频分析

深度伪造(Deepfake)是一种将图像篡改与AI相结合的面部替换方法。本文首先介绍了Deepfake的产生背景和发展状况,介绍了相应检测技术的研究状况,并对相关文献进行归纳;然后探究了Deepfake运行的基本构架和核心部件,给出了视频面部替换的基本流程和步骤,并阐释了利用自编码网络进行脸部图像训练和转换的原理;最后,从视频的基本信息、编辑痕迹、违背摄影规律、视频整体和案情五个方面与原始视频作对比,分析这类伪造视频存在的问题。深度伪造技术在推动娱乐和文化发展的同时也产生了大量恶意的换脸视频,对国家安全、社会稳定和个人隐私造成潜在的威胁,本文通过对Deepfake实现原理的研究和伪造视频特征的分析,希望能够为该类视频的真伪检验提供一定的理论支持。     

Characterization of Mitochondrial DNA Sequence Heteroplasmy in Blood Tissue and Hair as a Function of Hair Morphology*,†,‡

Abstract: This study characterizes mitochondrial DNA (mtDNA) sequence heteroplasmy in blood tissue and hair as a function of hair morphology. Bloodstains (127 individuals) and head hairs (128 individuals) were typed using the mtDNA LINEAR ARRAY? assay. A total of 1589 hairs were interpreted: 1478 (93%) were homoplasmic and 111 (7%) exhibited heteroplasmy at one or more positions. Seventy‐one percent (82/116) of individuals were homoplasmic, whereas 29% (34/116) exhibited heteroplasmy in at least one hair. The results demonstrate intra‐ and inter‐tissue differences in heteroplasmy within individuals. Sequence heteroplasmy among hairs from each individual varied from 0 to 90%; the frequency does not differ significantly with population group, cosmetic treatment, age, gender, medulla morphology, region of the scalp, hair growth phase, or, when comparing living and deceased donors. However, the results support a correlation between heteroplasmy and hair pigmentation; typically, lighter‐pigmented hairs exhibit a higher incidence of sequence heteroplasmy compared to darker hairs.     

Further evaluation of probabilities in human scalp hair comparisons

Placing value on associative hair evidence is an integral part of court presentation. A modified repeat of the hair probability study by Gaudette and Keeping has been undertaken, with steps taken to remedy shortcomings of the original work. The results of this study demonstrate that, with the application of rigid selection criteria, the frequency of coincidental matches in forensic science hair comparisons is low. It also demonstrates that routine hair classification is not feasible, because of inconsistency in examiner discrimination. The macroscopic selection of 5 to 13 mutually dissimilar hairs has been shown to be frequently unrepresentative of the microscopic range of features present in a known hair sample.     

Forensic DNA-typing of dog hair: DNA-extraction and PCR amplification

The forensic application of DNA-typing for the identification of dog hair provides objective evidence in the characterisation of traces found at crime scenes. During the past few years forensic dog identity testing has been improved considerably using multiplex PCR systems. However, DNA-typing from samples of one up to 10 dog hairs is often problematic in forensic science. A single dog hair contains very small quantities of DNA or the hair sample consists of hairs with roots of bad quality or even of broken hairshafts without roots. Here we describe an experimental study about dog hairs by means of a Ca(2+) improved DNA-extraction method, quantification and amplification.     

单根毛发角蛋白的分离与分析

本文用单根毛发(1～5cm)进行微量化角蛋白 SDS-梯度聚丙烯酰胺凝胶电泳分析,并对人与5种不同种属的动物毛发角蛋白进行了比较研究。结果表明,人与动物毛发角蛋白组分有明显差异,主要区别在于低分子量区域;用 N-(3-芘)马来酰胺标记毛发角蛋白巯基,进一步确定了毛发角蛋白中低硫蛋白位于45,000～52,000分子量范围,高硫蛋白位于<18,500分子量范围。人与动物毛发角蛋白的主要差异是高硫蛋白。作者认为,本实验方法对法医学毛发鉴别有一定的实用意义。     

Morphological characteristics of head hairs and hairs from other parts of the body in the population of Asia

The paper describes specific morphological features of hairs from the head, beard, chest, axilla, pubis of the native population of Syria, India, Lebanon, Jordan, Yemen, Nepal, Palestine, Bahrain, Iraq and some residents of the Eastern Europe (Russians, Belorussians, Ukrainians). The hairs were studied macroscopically and microscopically (light microscopy). Digital data on hair thickness and number of lines of cuticula pattern were analysed using methods of variance statistics. Original information on some macro- and microscopic characteristics of hair has been obtained for citizens of the above countries.