Comment on the Marshall-Hoare-Henssge model for estimating the time since death

Timewise temperature variations in objects that are undergoing unsteady heating or cooling is a commonly encountered problem in the thermal sciences. One particular area of application is the cooling of a body post-death and the use of body temperatures to estimate the time of death. Here, a new approach based on the theory of transient heat transfer is formulated to allow efficient calculation of unsteady conduction problems. The theoretically derived unsteady temperature models are compared with experimentally based correlations (the Marshall-Hoare-Henssge model). The two approaches are found to agree very well. With this new theoretically based approach, timewise temperature variation can be calculated for both large and small Biot number transient problems.     

IoT forensics: Exploiting unexplored log records from the HIKVISION file system

CCTV surveillance systems are IoT products that can be found almost everywhere. Their digital forensic analysis often plays a key role in solving crimes. However, it is common for these devices to use proprietary file systems, which frequently hinders a complete examination. HIKVISION is a well-known manufacturer of such devices that typically ships its products with its proprietary file system. The HIKVISION file system has been analyzed before but that research has focused on the recovery of video footage. In this paper, the HIKVISION file system is being revisited regarding the log records it stores. More specifically, these log records are thoroughly examined to uncover both their structure and meaning. These unexplored pieces of evidence remain unexploited by major commercial forensic software, yet they can contain critical information for an investigation. To further assist digital forensic examiners with their analysis, a Python utility, namely the Hikvision Log Analyzer, was developed as part of this study that can automate part of the process.     

中日两国在东亚区域内贸易中地位的变化及其影响

东亚区域内贸易比重的迅速上升是现阶段东亚贸易发展的一个重要特征。中国和日本作为东亚区域内两个最大的经济体,两国在东亚区域内贸易中的地位和影响力的变动对相互之间的经济合作以及区域内经济合作模式的选择,具有十分重大的影响。本文在分析东亚区域内贸易发展现状的基础上,从中间产品和最终产品的贸易结构与贸易竞争压力的角度,分析了中日两国在东亚区域内贸易中地位的变动及其影响。     

国际海盗问题与中国海上通道安全

作为世界贸易大国和能源进口大国,中国的发展越来越依赖于海外,海上通道安全对保障中国国家安全的重要性日益凸显。海盗作为一种国际犯罪行为,严重影响国际海上航运安全,也对中国海上战略通道安全构成现实威胁。海盗治理成为关系到中国海上通道安全的重大问题,必须采取积极有效措施加以解决。为此,我们必须进一步完善国内反海盗立法和反海盗机制;充分发挥联合国的作用,建立打击海盗、维护海上通道安全的长效机制;积极推动反海盗的国际和地区合作;增强防御海盗的力量和意识,重视远洋海军建设;坚持标本兼治,积极推进海盗所属国或地区的和平、发展和稳定。     

Psychiatric disorders and management of sexual offenders in the prison psychiatric consultation unit of Marseille

Since 2017, complaints of sexual violence have increased in France. At the same time, the management of sexual offenders has been at the center of international public health policies. The prevalence of mental disorders among sexual offenders is an essential field of research. There are some published studies on the prevalence of psychiatric disorders in sexual offenders in detention, but there are few recent published studies among French individuals who were detained. Our objectives were to determine the prevalence of psychiatric disorders among persons detained for sexual offenses and the level of care received according to their diagnosis. For this purpose, we carried out a retrospective observational study from January 2017 to October 2021 of all adult sexual offenders, whether accused or convicted, who were seen in the psychiatric consultation unit of Les Baumettes prison, Marseille, France. The primary outcome measure was the psychiatric diagnosis entered in the medical records. One hundred forty-two patients were included in analysis. All patients were men, and the majority (n = 97, 68.3%) of these patients presented with at least one psychiatric disorder, principally a personality disorder (31.7%). 10.6% presented with a schizophrenic disorder, 4.9% a bipolar disorder, 3.5% a depressive disorder, 5.6% pedophilic paraphilia, and 25.4% an addictive disorder. Their management and comorbid addictions were analyzed in subgroups for each psychiatric disorder. Patients appeared to receive an appropriate level of care for their diagnosed disorder. It seems important to develop structured assessment of recidivism risk for better management of sexual offenders.     

The systemic error in the vertical component of handgun bullet trajectory reconstructions

Establishing the path or trajectory of a fired bullet is an often recurring part of shooting incident reconstruction. The current study describes how gravitational pull causes a systemic error on the vertical component of a trajectory reconstruction. Bullet drop, drop angle, and vertical offset are explained and calculated for 10 different handgun/ammunition combinations over a range of distances up to 100 m. The presented results are intended to provide forensic firearm examiners with a reference frame for the magnitude of error introduced on handgun bullet trajectory reconstructions over distance. Threshold values of 20 and 30 m are proposed as conservative distances up to where bullet trajectories can be modeled as straight lines with subsonic/transonic handgun bullets and with supersonic handgun bullets respectively. Both the bullet drop and vertical offset will be below 5 cm at these distances for those categories. The drop angle will be below 0.3°.     

Effects of kinetic energy and firearm-to-target distance on fracture behavior in flat bones

This research implements a fractographic approach to investigate the relationships between kinetic energy, firearm-to-target distance, and various aspects of fracture behavior in gunshot trauma. Gunshot experiments were performed on pig scapulae (n = 30) using three firearms generating different muzzle (initial) kinetic energies, including a 0.32 pistol (103 J), 0.40 pistol (492 J), and 0.308 rifle (2275 J). Specimens were shot from two distances: 10 cm (n = 15) and 110 cm (n = 15). Features evaluated in fractographic analysis such as cone cracks, radiating cracks, crack branching points, and circumferential cracks could be easily identified and measured in flat bones and allowed for statistical comparison of crack propagation behavior under different impact conditions. Higher-energy bullets produced more radiating cracks, more crack branching points, and longer fracture lengths than lower-energy bullets. Distance had no significant effect on fracture morphology at the distances tested. That quantitative measures of crack propagation varied with energy affirms that kinetic energy transfer is important in determining the nature and extent of fracture in gunshot wounds and suggests it may be possible to infer relatively high- versus relatively low-energy transfer using these features. Ranges obtained with the three firearms exhibited considerable overlap, however, indicating that other variables such as bullet caliber, mass, and construction influence the efficiency of energy transfer from bullet to bone. Therefore, fracture morphology cannot be used to identify a specific firearm or to directly reconstruct the muzzle (initial) kinetic energy in forensic cases.     

Distinct age-related differences among victims in cases of suspected child abuse

Evidence describing age-related differences among children with suspected physical and sexual child abuse is lacking. We describe findings in severe cases of suspected abuse. Cases with 756 children <15 years old were included during 2001–2013 at the Department of Forensic Medicine, Aarhus University, using forensic evaluation documents, medical records, and court proceedings. Eight percent of children <4 years old died from child abuse, 36% through violence resulting in death, and 64% by manslaughter, whereas 1% > 4 years old died, solely by manslaughter. External injuries were mainly located to head and torso in children <4 years old, changing to the upper and lower extremities in older children. Child sexual abuse was suspected in 52% of cases with living children <4 years old, 83% of children 4–7 years of age, 88% of children 8–11 years of age, and 93% of children >12 years old. Anogenital findings were mainly caused by other medical conditions in children <4 years old, hymenal clefts in the superior half of the hymenal rim were almost exclusively found in children between 8 and 11 years of age, whereas both superficial and complete hymenal clefts in the inferior half of the hymenal rim were found in children >12 years old. The present study describes age-related differences in victims of suspected child abuse. Fatal versus nonfatal child physical abuse and the significance of hymenal findings in child sexual abuse could be studied further.     

Individuals lacking ridge detail: A case study in adermatoglyphia

Adermatoglyphia is a very rare autosomal‐dominant condition that is genetically inherited and causes an individual to be born without conventional ridge detail on either their palmar or plantar surfaces (the fingers and palms of the hands and the toes and the soles of the feet). While adermatoglyphia has been the focus of medical and genetic research, no previous research has been conducted with regard to the forensic recovery and identification of marks from an adermatoglyphic individual. By observation of ridge detail donated by an adermatoglyphic subject, the study uses different methods in order to capture fingermarks (methods include: inked capture, livescan (biometric) capture, cyanoacrylate fuming, ninhydrin enhancement, and physical developer). Unusually, the purpose of this paper ends up presenting a number of examples of an absence of evidence; unsuccessful attempts made to capture and enhance fingerprint ridge detail. This is determined over a range of standard means including "live" donations by the adermatoglyphic subject onto the Livescan system, and enhancements of latent donations. The subject shows to leave either insubstantial fingermarks with no detail, or no mark whatsoever.     

Detection of trace drugs of abuse in baby formula using solid‐phase microextraction direct analysis in real‐time mass spectrometry (SPME‐DART‐MS)

The intentional or unintentional adulteration of baby formula with drugs of abuse is one of the many increasingly complex samples forensic chemists may have to analyze. This sample type presents a challenge because of a complex matrix that can mask the detection of trace drug residues. To enable screening of baby formula for trace levels of drugs, the use of solid‐phase microextraction (SPME) coupled with direct analysis in real‐time mass spectrometry (DART‐MS) was investigated. A suite of five drugs was used as adulterants and spiked into baby formula. Samples were then extracted using SPME fibers which were analyzed by DART‐MS. Development of a proof‐of‐concept method was completed by investigating the effects of the DART gas stream temperature and the linear speed of the sample holder. Optimal values of 350°C and 0.2 mm/s were found. Once the method was established, representative responses and sensitivities for the five drugs were measured and found to be in the range of single ng/mL to hundreds ng/mL. Additional studies found that the presence of the baby formula matrix increased analyte signal (relative to methanolic solutions) by greater than 200%. Comparison of the SPME‐DART‐MS method to a traditional DART‐MS method for trace drug detection found at least a factor of 13 improvement in signal for the drugs investigated. This work demonstrates that SPME‐DART‐MS is a viable technique for the screening of complex matrices, such as baby formula, for trace drug residues and that development of a comprehensive method is warranted.