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981.
The ability to determine the age of fingerprints would be immeasurably beneficial in criminal investigations. We explore the possibility of determining the age of fingerprints by analyzing various compounds as they diffuse from the ridges to the valleys of fingerprints using matrix‐assisted laser desorption/ionization mass spectrometry imaging. The diffusion of two classes of endogenous fingerprint compounds, fatty acids and triacylglycerols (TGs), was studied in fresh and aged fingerprints on four surfaces. We expected higher molecular weight TGs would diffuse slower than fatty acids and allow us to determine the age of older fingerprints. However, we found interactions between endogenous compounds and the surface have a much stronger impact on diffusion than molecular weight. For example, diffusion of TGs is faster on hydrophilic plain glass or partially hydrophilic stainless steel surfaces, than on a hydrophobic Rain‐x treated surface. This result further complicates utilizing a diffusion model to age fingerprints.  相似文献   
982.
Acute mesenteric venous thrombosis (MVT) is a rare, but life‐threatening medical phenomenon. MVT is normally characterized by insidious onset, with nonspecific signs and symptoms. A high index of clinical suspicion is required for diagnosis, and emergency surgery is necessary to optimize the chances of patient survival, especially in the people aged more than 70 years. Surprisingly, based on my review of the literature, no fatal acute MVT case has been reported in the forensic literature. All reported such cases have been documented in medical literature, and most of them have been associated with underlying risk factors for venous thrombosis, such as hypercoagulable state, certain cancers, and stasis of the blood flow. Here, I report the case of a sudden unexpected death due to extensive intestinal ischemia and infarction with massive abdominal hemorrhage caused by acute MVT in a 72‐year‐old man without known underlying risk factors.  相似文献   
983.
Detection of aged fingerprints is difficult because they can degrade over time with exposure to light, moisture, and temperature. In this study, aging fingerprints were visualized by time‐resolved spectroscopy with an ultraviolet‐pulsed laser. Fingerprints were prepared on glass slides and paper and then stored under three lighting conditions and two humidity conditions for up to a year. The fluorescence intensities of the fingerprints decreased with time. Samples were stored in the dark degraded less than in sunlight or under a fluorescent lamp. Samples were stored under low humidity degraded less than under moderate humidity. As the storage period increased, a fluorescence emission peak appeared that was at a longer wavelength than the peak visible in earlier spectra. This peak was used for visualization of an aged fingerprint over time. An image of the fingerprint was not initially visible, but an image appeared as the time since deposition of the fingerprint increased.  相似文献   
984.
Many Americans own guns to protect themselves against other people, but there is evidence that both victimization and gun access increase suicide risk. We conducted qualitative interviews with informants of 17 suicide cases in New Orleans of the 60 who died between January 2015 and April 2016 to understand the relationship between past trauma, gun access and storage, and suicide. Nine cases had experienced a past trauma, including three who had recently had a family member killed by homicide. Eight died via firearm; of those, seven owned the guns they used to take their lives and stored them locked (but loaded) at home or in their cars. Preventing community violence and addressing its sequelae may be important for reducing suicides. A multi‐pronged strategy consisting of policies, education, and marketing will likely be needed to address the risk of suicide conferred by gun access.  相似文献   
985.
In December 2014, the legal blood alcohol limit for drivers in both Scotland and New Zealand was reduced from 80 to 50 mg/100 mL. This paper reports a retrospective study comparing changes in the toxicological findings in deceased drivers and motorcyclists before and after the limit change in both jurisdictions. A year of fatal motor vehicle crashes prior to and following the limit change is examined for both countries. In Scotland, there was an increase in drug prevalence among fatally injured drivers and motorcyclists, with the use of all drug groups increasing after the limit change, with the exception of cannabinoids. In New Zealand, there was a reduction in cases involving drugs only, but increases in the numbers of deceased drivers and motorcyclists positive for alcohol only and co‐using alcohol and drugs.  相似文献   
986.
Few studies have compared performance on neurocognitive measures between violent and nonviolent schizophrenia samples. A better understanding of neurocognitive dysfunction in violent individuals with schizophrenia could increase the efficacy of violence reduction strategies and aid in risk assessment and adjudication processes. This study aimed to compare neuropsychological performance between 25 homicide offenders with schizophrenia and 25 nonviolent schizophrenia controls. The groups were matched for age, race, sex, and handedness. Independent t‐tests and Mann–Whitney U‐tests were used to compare the schizophrenia groups’ performance on measures of cognition, including composite scores assessing domain level functioning and individual neuropsychological tests. Results indicated the violent schizophrenia group performed worse on measures of memory and executive functioning, and the Intellectual Functioning composite score, when compared to the nonviolent schizophrenia sample. These findings replicate previous research documenting neuropsychological deficits specific to violent individuals with schizophrenia and support research implicating fronto‐limbic dysfunction among violent offenders with schizophrenia.  相似文献   
987.
Several studies have reported on wide‐spread contamination of U.S. paper currency with cocaine and to a lesser extent other illicit drugs. Canines are trained and employed to search for and alert to drugs. Canine alert to currency has been used as evidence that currency has been directly involved in illicit drug trafficking to justify currency seizure and forfeiture. This assertion, particularly when the only evidence is based upon canine alert, has been challenged in the courts considering that most currency in circulation is contaminated with cocaine. Comprehensive review of the scientific literature establishes that (i) 67–100% of circulated U.S. currency is contaminated with cocaine ranging from a few nanograms to over one milligram/bill (ii) various biological and environmental parameters impact canine alert to drugs. It is concluded that canine alert to U.S. currency is not sufficiently reliable to determine that currency was directly used in an illicit drug transaction.  相似文献   
988.
With an increase in the creation and maintenance of personal websites, web content management systems are now frequently utilized. Such systems offer a low cost and simple solution for those seeking to develop an online presence, and subsequently, a platform from which reported defamatory content, abuse, and copyright infringement has been witnessed. This article provides an introductory forensic analysis of the three current most popular web content management systems available, WordPress, Drupal, and Joomla! Test platforms have been created, and their site structures have been examined to provide guidance for forensic practitioners facing investigations of this type. Result's document available metadata for establishing site ownership, user interactions, and stored content following analysis of artifacts including Wordpress's wp_users, and wp_comments tables, Drupal's “watchdog” records, and Joomla!'s _users, and _content tables. Finally, investigatory limitations documenting the difficulties of investigating WCMS usage are noted, and analysis recommendations are offered.  相似文献   
989.
Ex-armed forces personnel constitute the largest known occupational group in prison but there is little evidence regarding their mental health, or substance misuse, needs. A total of 105 participants were interviewed and measures assessing symptoms of common mental health (CMH) problems and substance misuse were completed along with a review of their health care records. Forty (38%) participants screened for current CMH problems (CCMH) and high levels of dual symptomology and alcohol misuse were assessed. Thirty-nine (37%) had a mental health diagnosis recorded, most commonly for post-traumatic stress disorder (PTSD), depression and personality disorder. Those who screened for a CCMH problem were more likely to have pre-service vulnerability to negative health outcomes and those with dual symptomology were more likely to have experienced deployment during their service. Findings suggest the mental health needs of this group are similar to the general prison population. Potentially higher prevalences of PTSD and alcohol misuse may direct service provision.  相似文献   
990.
Bows and arrows are ancient weapons that have risen and fallen as the preeminent armaments used by man. Because of the ubiquity of firearms, fatalities from archery injuries in the United States have radically declined. However, when deaths involving this weapon do present themselves, the paucity of reference materials can be a hurdle for forensic pathologists and other forensic scientists. This article will provide a brief history of the origins of the bow and the inception of the compound bow. Comparing and contrasting the structures comprising a traditional bow to those of the modern compound bow will provide insight into how these components function in unison to propel arrows.  相似文献   
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