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131.
The aim of this paper is to evaluate the risks associated with the use of fake fingerprints on a livescan supplied with a method of liveness detection. The method is based on optical properties of the skin. The sensor uses several polarizations and illuminations to capture the information of the different layers of the human skin. These experiments also allow for the determination under which conditions the system is deceived and if there is an influence respectively of the nature of the fake, the mould used for the production or the individuals involved in the attack.These experiments showed that current multispectral sensors can be deceived by the use of fake fingerprints created with or without the cooperation of the subject. Fakes created from direct casts perform better than those produced by fakes created from indirect casts. The results showed that the success of the attack is influenced by two main factors. The first is the quality of the fakes, and by extension the quality of the original fingerprint. The second is the combination of the general patterns involved in the attacks since an appropriate combination can strongly increase the rates of successful attacks.  相似文献   
132.
The purpose of this research is to assess the vulnerabilities of a high resolution fingerprint sensor when confronted with fake fingerprints. The study has not been focused on the decision outcome of the biometric device, but essentially on the scores obtained following the comparison between a query (genuine or fake) and a template using an AFIS system. To do this, fake fingerprints of 12 subjects have been produced with and without their cooperation. These fake fingerprints have been used alongside with real fingers. The study led to three major observations: First, genuine fingerprints produced scores higher than fake fingers (translating a closer proximity) and this tendency is observed considering each subject separately. Second, scores are however not sufficient as a single measure to differentiate these samples (fake from genuine) given the variation due to the donors themselves. That explains why fingerprint readers without vitality detection can be fooled. Third, production methods and subjects greatly influence the scores obtained for fake fingerprints.  相似文献   
133.
Abstract: The few available studies on fetal age estimation concern very small samples, and statistical analysis is sometimes inadequate. In this survey, we used germs of deciduous teeth to estimate fetal age. Forty‐nine fetuses and 40 mandibles were scanned, and observations and measurements were made on DentaScan images. After checking their repeatability and reproducibility (analysis of variance), we defined thresholds using Fisher’s linear discriminant analysis to calculate the probability that a fetus was over or below a predefined age threshold. The forensic threshold which is of particular interest in France is 22 weeks amenorrhea. Relationships between fetal age and deciduous germ measurements were then sought by multiple linear regression. The thresholds gave very good results: 91.84% of good probability for the threshold of 22 weeks amenorrhea with no chance of error. The most precise age evaluation obtained nevertheless gave a range of ±4.6 weeks amenorrhea, so greater accuracy is still needed.  相似文献   
134.
Recent years have been characterized by a series of publications in the field of firearms investigation questioning the reliability and objectivity of such examination. This research investigates new solutions to decrease the subjective component affecting the evaluation that follows the comparison of impressions left by a firearm on the surface of spent cartridge cases. An automatic comparison system based on 3D measurements has been developed and coupled to a bivariate evaluative model allowing assigning likelihood ratios. Based on a dataset of 79 pistols (all SIG Sauer 9 mm Luger caliber), the system shows a very high discriminating power and the LRs that it provides are very indicative of the true state under both the prosecution and the defense propositions. For example, likelihood ratios exceeding a billion are predominantly obtained when impressions originating from the same source are compared. The system is also characterized by relatively low rates (≤1%) of misleading evidence depending on the firearm considered.  相似文献   
135.
Kratom is a plant originating in Southeast Asia that has been used for its dose-dependent stimulant and opioid effects. The main active compound in kratom is mitragynine, an alkaloid with affinity for the mu-opioid receptor. Toxicity and fatalities related to kratom use have increased substantially in recent years. In this case report, we describe a 44-year-old man who was found deceased in bed. The only significant finding at autopsy was abdominal distension with >4 L of ascites. Toxicology testing was performed on femoral blood which showed 79 ng/mL of hydromorphone, 560 ng/mL of mitragynine, and 240 ng/mL of olanzapine. In addition, creatinine and urea in vitreous humor were significantly elevated, consistent with renal impairment. Death was attributed to hydromorphone toxicity with mitragynine being a contributing factor.  相似文献   
136.
An analytical strategy for identification by an LC–MS/MS multitarget screening method and a suitable LC–MS/MS based quantification were developed for the psychotropic drug phenibut. The samples analyzed were collected during traffic control and were associated with driving under the influence of drugs. A positive sample for phenibut was identified in a single case of driving under the influence. The quantification revealed a drug concentration of 1.9 μg/mL. An interaction with blood alcohol (BAC = 0.10%) was discussed as the explanation of the way of driving and deficit manifestations observed (swaying, nystagmus, quivering of the eyelid, and reddened eyes). According to the available information, the quantified phenibut concentration could be explained by an intake of four tablets (self-reported) during the day containing 250 mg of the drug. Chromatography was performed with a Luna 5 μm C18 (2) 100 A, 150 mm × 2 mm analytical column, and a buffer system consisted of 10 mM ammonium acetate and 0.1% acetic acid (v/v) included in mobile phases marked as A (H2O/methanol = 95/5, v/v) and B (H2O/methanol = 3/97, v/v). An effective limit of detection (LOD = 0.002 μg/mL) could be achieved for the multitarget screening method. The quantification of phenibut was performed on a second LC–MS/MS system with LOD/LOQ values of 0.22/0.40 μg/mL. Since phenibut quantification data are rare, the presented information can be used with caution for evaluation of positive cases in the future.  相似文献   
137.
Fat embolism syndrome (FES) is a potentially life-threatening condition that develops when fat embolism leads to clinical symptoms and multisystem dysfunction. The classic triad of respiratory distress, neurologic symptoms, and petechial rash are non-specific, and the lack of specific laboratory tests makes the diagnosis of FES difficult. Although FES is most common after long bone fractures, multiple conditions some of which are atraumatic have been associated with the development of FES. We report a case of FES that occurred in the setting of a non-traumatic compartment syndrome of the upper extremities. The pathologic and clinical findings, pathophysiology, diagnostic challenges, and pathologic methods to properly diagnose FES are discussed with a review of the relevant literature. This case highlights the importance of the autopsy in making a diagnosis of FES in cases where death could otherwise be incorrectly attributed to multi-organ system failure, shock, or sepsis.  相似文献   
138.
Digital investigation of anthropological material through computed tomography (CT) offers several new opportunities in morphometrics. However, an object measured with computer-assisted methods does not necessarily exactly match the original one. The scanning and surface reconstruction of the object induce some alterations, and data acquisition is prone to measurement uncertainty. The purpose of this research is to evaluate the intra- and inter-observers variations in medical CT scan measurements of a known-size phantom and two dry crania. Two software packages, AMIRA and Treatment and Increased Vision for Medical Imaging (TIVMI), which use different techniques of surface reconstructions, were compared. The mean difference between the measurements was lower for TIVMI, using an objective algorithm based on the half-maximum height (HMH) protocol in three dimensions (3D). AMIRA can induce up to a 4% error in known measurements and 5% uncertainty in dry skull measurements. This study emphasises the risk of object shape alteration in each step of its digitisation.  相似文献   
139.
In this article different approaches are distinguished in order to solve the question of what has to be done if a demented patient behaves in a manner which is found to be inconsistent with his previously expressed wishes. Positions vary, from implementing the advance directive to not implementing the advance directive. The article defends a compromise position by holding that the exact circumstances of each case should be weighed against each other to determine the outcome and to provide an answer to the research question.  相似文献   
140.
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