Time-dependent change in the microbiota structure of seminal stains exposed to indoor environmental.

Seminal stains acquired from fabric surfaces stand as pivotal biological evidence of utmost significance for elucidating sexual assault cases. The ability to determine the temporal aspect of a forensic incident via the analysis of a biological specimen found at the crime scene is crucial in resolving most cases. This study aimed to investigate the time-dependent change in the microbiota structure of human seminal stains exposed to indoor environmental conditions. Stains on polyester fabric generated using semen samples from five male volunteers were kept indoors for varying durations of up to 20 days, followed by sequencing of the V1-V9 regions of the 16S rRNA gene of the microbial DNA extracted from the stains. The acquired data provided the taxonomic composition, and microbial alterations across different days were examined. The most abundantly detected phyla in all samples were Firmicutes, Proteobacteria, and Bacteroidetes, and the relative abundances of bacteria were observed to change over time. Statistically significant changes at the species level were found for Treponema medium, Corynebacterium tuberculostearicum, Faecalibacterium prausnitzii, and Anaerostipes hadrus. Alterations observed in the samples between the analyzed time periods were investigated. The changes during the specified time periods were examined, identifying rare bacterial species that were initially present on certain days but later ceased to exist in the environment. Conversely, bacterial species that were absent before exposure but emerged at a later stage were also identified. The findings of this study demonstrate that species-level evaluations, in particular, can provide crucial insights into semen stain age.

The uselessness of using salivary microbiota in forensic identification purposes of a person with recent antibiotic use.

The detection of microbial flora changes in saliva samples because of antibiotic use through advanced molecular genetic analysis is important for forensic and clinical applications. This study aims to reveal the variability in the microbial structure of human saliva after antibiotic use with metagenomic analysis techniques from a forensic point of view. Within the scope of the study, saliva samples were collected from patients who were under the effect of regional anesthesia to be administered a standardized course of antibiotic therapy that lasted for a week. The analysis was conducted on 56 saliva samples from 14 individuals over four different time intervals. Isolation of the 16S rRNA region and PCR analysis were performed prior to sequence analysis to determine the microbiome structure of the samples at phylum, genus, and species levels. As expected, changes were observed in bacterial species found in saliva samples after administration of antibiotics and this was linked to the specific type of antibiotics that were administered. This change was statistically significant for Firmicutes, Spirochetes, and Verrucomicrobiota. Furthermore, although the oral microbiome tends to return to its former state at the phylum and genus level within a 4-week period after the start of antibiotic use, it is observed that the change, especially in some bacterial species, still continues. The findings of this study show that because of the inability of stabilization at species-level in a period of 4 weeks from the start of antibiotic use, it is not suitable to assess saliva samples at species-level for forensic identification.

Evaluation of Third Molar Maturity Index by Cone Beam Computed Tomography in Legal Age Estimation: A Preliminary Study.

ABSTRACT: This retrospective study aimed to evaluate the accuracy and applicability of the third molar maturity index (I 3M ) for discriminating Turkish minors from adults, and its relationship with chronological age using cone beam computed tomography (CBCT). A total of 122 CBCT scans of Turkish individuals (55 boys and 67 girls) aged 13 to 23 years were evaluated using the I 3M cutoff value. Chronological age gradually decreased as the I 3M value increased. The overall accuracy was 95.9%. The sensitivity and specificity of this test were 93.5% and 97.4%, respectively. Positive predictive value was 95.6%. The intraclass correlation coefficient values of the I 3M for the intraobserver and interobserver agreements were 0.998 and 0.996, respectively. This study showed relatively higher reproducibility of measurements on CBCT scans than on panoramic radiographs in the literature. Cone beam computed tomography may be advantageous and preferred over panoramic radiographs in distinguishing the legal age threshold of 18 years according to Cameriere's method when a more extensive investigation is needed to support the solution of challenging and uncertain cases in forensic medicine.

Evaluation of the detectability of different ages of bloodstains on fabrics in different washing conditions and at various wavelengths.

PURPOSE: The detection of bloodstains at crime scenes is extremely useful in forensic investigations. This study aimed to investigate the effects of washing temperature, fabric type, fabric color, and stain age (time from staining to laundering) on the detection and identification of bloodstains on fabrics after washing. MATERIAL AND METHOD: A total of 240 fabrics (4 different colors and 5 different types) were stained with blood and washed in 4 different washing temperatures with 3 different lag times. The evaluations of fabric images were performed using the FLS system (Forenscope-Mobile Multispectral UV-VIS-IR Imaging Systems®) on a total of 1200 images using 5 different wavelengths and filter options. The bloodstained areas of the fabric pieces were then excised, and the hemoglobin presence was analyzed using the SERATEC® HemDirect hemoglobin test. RESULTS: The analyses of laundered samples using the FLS system revealed that the best images were obtained from velvet, cotton fleece, denim, and polyester fabrics, in that order. Except for polyester fabrics, the SERATEC® HemDirect hemoglobin screening test, which was used to detect bloodstains on fabrics, showed positive results after washing at low temperatures (approximately 15 °C and 30 °C). At higher temperatures (60 °C and 90 °C), the SERATEC® HemDirect hemoglobin test yielded negative results. CONCLUSION: The fabric type and color played a crucial role in stain detection using the FLS system on the laundered fabrics. The FLS system and the SERATEC® HemDirect hemoglobin test revealed that stain age had a limited effect on the stain's detectability.

Sex estimation from biometric face photos for forensic purposes.

Sex estimation is an important parameter in cases where individuals need to be identified in forensic cases. Biometric photographs are a form of a passport photo with specific dimensions and features established by the International Civil Aviation Organization, which are read and digitally stored in appropriate devices, are used in travel documents, and are of high quality (at least 600 dpi). This study aims to reveal anthropometric data for estimating sex in Turkish adult population from facial images conforming to biometric photography criteria. Within the scope of this study, biometric facial images of a total of 334 participants, 146 female and 188 male, between the ages of 20 and 79 were used. The photos were taken using a Nikon D5100 and flat front lighting from a distance of 1 m. ImageJ 1.50i software was used to process these images. Statistical analysis was performed using descriptive statistics and discriminant analysis tests. Among the 11 variables on sex estimation, the highest accuracy rate of 78.1% was obtained with the measurement between Gonion points. However, sex estimation could be made with an accuracy of 80.5% by including all age groups and all variables, and when age-specific data were used, it was observed that these accuracy rates increased significantly in all three age groups (84.6%, 89.2%, 85.2%, respectively). Therefore, we are suggesting that using age-specific data generated for estimation in different age groups. Consequently, it has been shown that successful sex estimation can be done by formulas derived from biometric facial images in this study.

Investigating changes in salivary microbiota due to dental treatment: A metagenomic analysis study for forensic purposes.

The advent of next generation sequencing techniques as well as the existing traditional culture methods has enabled metagenomic studies on the usability of microbiomes for the forensic identification of individuals to gain momentum. However, before the utilization of microbiomes as a potential technique for real forensic case resolutions, it is necessary to understand the stability of the microbiota compositions in an individual's biological samples and the factors responsible for their variations. In the present study, we compared the microbiota compositions present in the saliva of individuals with active dental caries before and after treatment from a forensic and clinical perspective using an approach based on the sequencing of all the variable regions (V1-V9) of the bacterial 16 S rRNA gene. For this purpose, 10 individuals were included in the study comprising of 8 individuals between the ages of 18-50 years with at least 3 deep dentin caries as patients and 2 healthy individuals without any dental or gingival diseases as controls. Saliva samples were collected from the patients at two timepoints, before and after treatment, as well as from the healthy individuals (before and after control) at an interval of 1 month. The collected 20 saliva samples were subjected to metagenomic analysis using the MinION device, which was developed by Oxford Nanopore Technologies (ONT Oxford, UK). Bioinformatic analyses were performed on the obtained data and the results were evaluated using statistical comparison methods and alpha/beta diversity analyses within the scope of the study objective. On evaluation using the distance metrics, it was observed that the microbial compositions in the saliva of individuals with active caries remained relatively stable after treatment. However, the relative abundance levels of bacteria of 28 genera and species showed statistically significant differences before and after treatment (p < 0.05). As a result, although the composition of salivary microbiome remained relatively stable after caries treatment, there were significant changes in many types of bacteria, especially at the species level, between the BT and AT samples. Our results provide a framework for further forensic and clinical investigations regarding the factors that affect human salivary microbiome diversity.

Estimation of sex from computed tomography images of skull measurements in an adult Turkish population.

BACKGROUND: Nowadays, data on the anthropometric measurements of populations is needed in many areas, especially forensic and legal. Using various methods, researchers obtain various data such as race, sex, and age, and thus provide identification of the material used. Morphological or metric methods are often used for identification. PURPOSE: To evaluate the usefulness of the results of skull measurements using computed tomography (CT) to determine sex in a Turkish population. MATERIAL AND METHODS: We analyzed 300 male and 300 female CT images of Turkish individuals with an age range of 21-50 years. Maximum cranial length, maximum cranial breadth, bimastoid diameter, bizygomatic diameter, and bigonial breadth were measured by CT tomography. All data were subjected to discriminant function analyses for estimating sex. Intra-observer and inter-observer variances of the measurements were examined using intraclass correlation coefficient analysis. RESULTS: Discriminant function analysis indicated that there was a significant difference between male and female with 88% accuracy. Discriminant function for estimation of sex was obtained with satisfactory accuracy rates for the parameters used. CONCLUSION: This study confirms that skull measurements show sexual dimorphism in the Turkish population, and also suggests that it may be useful to use CT to assess skull anthropometric measurements.

Publication rates of abstracts presented at the annual scientific meetings held by the American Academy of Forensic Sciences in 2011 and 2016.

Prior research evaluating the papers presented in forensic sciences in international meetings is scant. This study determines the possible predictions concerning publications by comparing the publication rates, publication years, and presentation types, time until publication, participating countries, and criteria of the published journals in the American Academy of Forensic Sciences (AAFS). The publication rates of abstracts presented at scientific meetings of AAFS, a prestigious forensic science organization, along with the aforementioned components and the extent of their contribution in 2011 and 2016 were investigated. The abstracts presented at the AAFS meetings in 2011 and 2016 were reviewed retrospectively within the scope of this study. The Web of Science, PubMed, Scopus, Science Direct, and Google Scholar databases were searched using a specified process that included the title, first and last author surnames, and keywords. Results revealed that approximately 21% and 24% of the papers presented at the 2011 and 2016 AAFS meetings, respectively, were published. Considering the publication rates of abstracts according to sections, the publication rates for the 2011 AAFS meeting ranged from 4% (questioned documents) to 31% (anthropology) and from 5% (questioned documents) to 32% (pathology/biology), on average, for the 2016 AAFS meeting. It was determined that the papers were largely published in the Journal of Forensic Sciences for both annual scientific meetings. Future studies should concentrate on the obstacles to the publication of papers presented at such prestigious organizations and strategies to facilitate the publication process such that they do not lose their value over time.

Assessment of the exclusion potential of suspects by using microbial signature in sexual assault cases: A scenario-based experimental study.

Sexual assault offences are one of the most serious crimes committed against a person, typically rank only second to homicide, and represent one of the major challenges in forensic sciences. In some cases of sexual assault, there may be more than one suspect and the analysis of the biological evidence with currently available methods such as human DNA analysis may not yield results. In this study using the designed experimental model (with different experimental scenarios that can be designed), it was aimed to investigate the effectiveness of the microbiome profile for the identification of the offender by comparing the microbiome structures of the suspects' saliva samples with the mixed samples on the victim (saliva transmitted on breast skin) within the first 48 h after a sexual assault. For this purpose, a total of 44 samples was collected from four healthy females and four healthy males aged 20-50 years. Microbiome profiles of 44 samples in four groups containing saliva, breast skin and mixed samples were determined with the IIlumina HiSeq platform. Differentiation between samples were calculated by beta-diversity analysis methods by using QIIME software (v1.80). To compare the differentiation among samples and groups, unweighted UniFrac distance values were applied. Eight dominant microbial genera accounted for 86.15% of the total bacterial population in male saliva samples and were composed of Fusobacterium, Haemophilus, Neisseria, Porphyromonas, Prevotella, Rothia, Streptococcus and Veillonella. These genera constituted 76.72% of the bacterial population in mixed samples, whereas they constituted 34.40% of the bacterial population in the breast skin samples. Results of this study show that bacterial DNA in saliva can be recovered from saliva transmitted breast skin within at least 48 h. In conclusion, it has been found that examination of the microbiota of the saliva transmitted to breast skin of a sexual assault victim as a forensic tool may have the potential to determine the offender of the incident among the suspects or to reduce the number of suspects. Supporting the results of this study with further studies using parameters such as different case models, different body regions, larger time periods and a higher number of participants will be beneficial to draw accurate conclusion of the judicial case.

Evaluation of the relationship between the detectability of seminal stains on laundered fabric and stain age.

In some cases of sexual assault that are not reported to judicial authorities within a certain time, it is important to detect and identify seminal stains on laundered fabrics. In this study, we aimed to reveal the effect of the time from staining to laundering on the detectability and identification of seminal stains on laundered clothes. A total of 180 pieces of fabric (four different colours and five different types) were stained with seminal fluids, and three different lag times (12 hours, 1 week and 1 month) from staining to laundering were used. Three different laundering protocols were applied to these fabrics after staining. The built-in camera of the Mobile Multispectral UV-VIS-IR Imaging System® was used to take photos (1260 in total) of the stains with seven different wavelength and filter options, and the obtained images were evaluated. The Seratec® PSA Semiquant test was used to analyse the presence of prostate-specific antigen (PSA) in the seminal stains laundered after different lag times. We observed that in examining with the forensic light source (FLS) system, the time from staining to laundering affected the detectability of seminal stains on pieces of cloth. The best fluorescence was obtained in the examination of semen-stained fabric with FLS, particularly when the fabric was not laundered for one month after staining. On the other hand, the time from staining to laundering had a more limited effect on PSA test positivity than on the results of the examination with FLS.

Relationship of injuries detected in fatal falls with sex, body mass index, and fall height: An autopsy study.

Falls from height are the most common cause of blunt trauma after traffic accidents. The focus of this retrospective study was to analyze the relationship between injuries in fatal falls and fall height, body mass index (BMI), and sex in 206 autopsy reports. Age, sex, weight, height, place of the fall, fall height, period between the incidence and death, external examination findings in the autopsy, intracranial findings, fractures, internal organ injuries, and information about the causes of death were recorded. Accidents and men were the largest groups. Injuries to the upper and lower extremities were frequently detected in accidents. Lower extremity injuries were more common in women. The occurrence of head and neck injuries were rare in overweight individuals. When evaluated by manner of death, there were differences in extremities and posterior body injuries. There was no difference between sex in terms of autopsy findings. It was observed that the injuries increased as the height increased. There was a statistical difference between the BMI groups in terms of liver, rib and sternum injuries. The most common cause of death was head injuries. Many factors have been known to affect injury patterns in cases of falls from height. Fall height, BMI, and gender are just a few of these factors. This study will be beneficial to support the findings of this study with larger-scale studies and statistical modeling that consider more factors affecting injuries in cases of falls.

Sex estimation from foramen magnum parameters in adult Turkish population: A computed tomography study.

Identification of skeletal relics is crucial for medicolegal purposes. Sex estimation is one of the critical parts providing the identification of skeletal relics. In forensic practice, sex estimation requires multidisciplinary studies of such as forensic medicine, anatomy, dentistry and radiology. Recently, radiological studies on this subject have been increasing with the developing technology. The objective of this study is to examine the usage of radiological dimensions of foramen magnum for sex estimation in human skulls by developing discriminant functions in Turkish population. We analyzed 600 (300 males and 300 females) Computerized Tomography (CT) images of Turkish individuals aged between 21 and 50. Four measurements were obtained from CT images. All measurements in males were significantly greater than in females, and they provided the higher sex classification accuracy. The area of the foramen magnum calculated by Radinsky's formula was the best measurement for sex estimation with a 75% accuracy rate. In conclusion, the CT images of foramen magnum show sexual dimorphism in our population. To use population specific data would be the most appropriate approach for sex estimation.

Legal and ethical responsibilities of physicians in coercive situations, such as natural disasters.

BACKGROUND: The relationship between the physician and the patient is based on the provisions of the proxy agreement. The attitude of the physician and the legal and ethical responsibilities of this attitude in an event of force majeure, such as severe natural disaster (earthquake), during a risky operation should be discussed. The aim of the present study was to present the opinions of the related professions about the subject and to discuss the subject on an ethical and legal ground. METHODS: A total of 207 volunteers including 121 physicians working at the Cerrahpasa Faculty of Medicine at Istanbul University and 86 lawyers registered at the Istanbul Bar Association completed the questionnaires. Statistical analysis of data acquired from the questionnaires was performed using SPSS 21.0. RESULTS: Of the participants, 76.8% stated that abandoning the patient by the physician considering his/her own safety during a severe natural disaster is ethically problematic. However, 68.1% of the participants stated that physicians would not be facing any criminal sanctions in response to his/her attitude. When the answers from both occupational groups were compared separately, it was found that 26.4% of the physicians and 39.5% of the lawyers stated that the act in question has both legal and ethical liability. CONCLUSION: In the present study, no complete consensus was observed either between or within two occupational groups. It was concluded that the meetings in which the subject is discussed and is based on a concrete ground by both occupational groups should be held.

Role of bite mark characteristics and localizations in finding an assailant.

The location, size, and number of bite marks can be used as a beneficial indicator of the crime type and feasible group of suspects. This study aims to present information about the bite mark locations, the bite mark characteristics, and the perpetrator's profile based on three cases which were carried out by the same biter. The attack bites, which observed in all of the three cases, were characterized by serious wounds and tissue loss. Analysis of bite mark characteristics and bite mark localizations of these three cases by the relevant experts provided helpful information for the police units which searched for the assailant. But, in order to conduct criminal profiling from bite marks objectively, the number of case series is advised to be expanded.

Development of dental charts according to tooth development and eruption for Turkish children and young adults.

PURPOSE: In this study, we aimed to develop dental charts for Turkish children and young adults of both genders within the age group of 4.5-22.5 years according to tooth mineralization and eruption in a format similar to that proposed by AlQahtani et al. MATERIALS AND METHODS: In total, 753 digital panoramic radiographs from 350 males and 403 females were assessed. The permanent teeth were evaluated according to the classification system described by Demirjian et al. The eruption stage was assessed with Bengston's system, which was modified by AlQahtani et al at four points. RESULTS: Teeth generally developed earlier in females than in males. This was particularly notable in the age group of 5-14 years. However, this difference was usually visible in only one stage, not in all teeth. It has been determined that the mixed dentition period ended with the shedding of the second deciduous molars in both genders. CONCLUSION: The dental charts presented here included information that could be beneficial to dental clinicians in making appropriate diagnosis and planning orthodontic and surgical procedures. These charts also provided datasets for preliminary dental age estimation in Turkish children and young adults.

Radiological age estimation: based on third molar mineralization and eruption in Turkish children and young adults.

Radiographic evaluation of mineralization and eruption stages of third molars using dental panoramic radiographies can be an efficient tool for chronological age estimation in both forensic sciences and legal medicine. The third molar tooth is utilized for dental age estimation about the age span of 15-23 years because it represents the only tooth still in development. The aim of this study is to obtain and analyze data regarding third molar development and eruption in Turkish population for dental age estimation. A total of 744 dental panoramic radiographies of 394 female and 350 male subjects aged between 8 and 22 years were examined. Third molar development was determined according to the Nolla classification system, and eruption was assessed relative to the alveolar bone level. Mandibular and maxillary third molars were generally found at similar stages of development on both sides. Nolla stage 6 (completed crown calcification) was reached at around the age of 15 in both maxillary and mandibular third molars in both sexes. Alveolar emergence was at around the age of 16 in males and around age of 17 in females. Although third molars' eruption shows greater variability than development of third molars, data which were obtained from this study about eruption of these teeth can be supportive to development data for age estimation.