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1.
Jennifer Paola Pascali Ph.D. Diego Palumbo M.Sc. Federica Umani Ronchi Ph.D. Francesco Mari Ph.D. Alessia Fioravanti M.Sc. Elisabetta Bertol Ph.D. 《Journal of forensic sciences》2020,65(1):189-192
Through the measurement of ethyl glucuronide in hair (hETG), it is possible to assess chronic alcohol abuse over time. In this paper, we present a study on hETG in Italian prison inmates. Analyses were performed by LC-MS according to a previously published method. Results were evaluated using the cut-offs established by the Society of Hair Testing. Positives samples (ETG > 30 pg/mg) accounted for 6% of all subjects, with concentrations ranging from 42 pg/mg up to 270 pg/mg, abstinent subjects (ETG < 7 pg/mg) accounted for 88%, and moderate alcohol consumption (7 < ETG < 30 pg/mg) for 6% of the subjects. No females displayed ETG values above 30 pg/mg. Among positive samples, only two subjects did not declare heavy alcohol consumption and were found strongly positive at 210 and 270 pg/mg. To the best of our knowledge, this represents the first study on ETG hair concentration on prison inmates. 相似文献
2.
Kevin J. Farrugia Ph.D. Danielle Hunter B.Sc. Clarice Wilson B.Sc. Stef Hay B.Sc. Paul Sherriffs B.Sc. Paul Deacon B.Sc. 《Journal of forensic sciences》2020,65(1):248-254
This study presents a number of pseudo-operational trials on plastic bags investigating the double- and co-fuming process of a one-step fluorescent cyanoacrylate (LumicyanoTM) in comparisons with the two-step process with basic yellow 40 (BY40) staining for the detection of latent fingermarks. The results demonstrate that both Lumicyano solution and dye contribute to the increased detection of latent fingermarks during the double-fuming process (trial 1). Co-fuming the Lumicyano solution and dye separately (at a concentration of 8%) but simultaneously was less effective than 8% Lumicyano (trial 2). Co-fuming Lumicyano 8% and an additional 8% Lumicyano dye by weight was more effective than Lumicyano 8% (trial 3), possibly due to increased fluorescent material deposition during co-fuming allowing for better visualization. The use of BY40 after Lumicyano resulted in a considerable increase in detected fingermarks. 相似文献
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Ana Celeste Ximenes Oliveira Ph.D. Alexandre Leão Ph.D. Karla Balzuweit Ph.D. Livia Siman Ph.D. Oscar Nassif Mesquita Ph.D. Luiz Orlando Ladeira Ph.D. Luiz Alberto Cury Ph.D. 《Journal of forensic sciences》2019,64(6):1867-1872
The optical and morphological properties of resveratrol were investigated. This nontoxic fluorescent natural material, emitting in the visible blue light, was used as an optical marker, enabling the enhancement of the image contrast coming from relief pictures marked on challenging surfaces. By applying appropriated imaging softwares, this marker was verified to be very useful in the latent fingerprint recognition deposited on different wood surface types, mainly those with high level of roughness, where conventional forensic materials do not allow effective fingerprint image visualization. 相似文献
5.
Kristopher D. Wisniewski Ph.D. Nicholas Cooper M.Sc. Vivienne Heaton Ph.D. Colin Hope B.Sc.; M.Sc. Duncan Pirrie Ph.D. Andrew J. Mitten M.Geo. Jamie K. Pringle Ph.D. 《Journal of forensic sciences》2019,64(5):1530-1539
Police witness intelligence stated a murdered adult male “Fred” had been vertically buried in wooded hilly terrain 30 years ago in the Midlands, U.K. Conventional search methods were unsuccessful; therefore, the police requested a geophysical investigation to be undertaken to determine whether “Fred” could be detected. A multiphased geophysical approach was conducted, using bulk ground conductivity and metal detectors, then follow‐up magnetics and ground penetrating radar (GPR) survey profiles on electromagnetic (EM) anomalous areas. A tight grid pattern was used to account for the reduced target size. Relatively high‐resolution EM and GPR techniques were determined optimal for this terrain and sandy soil. Geophysical anomalies were identified and the most promising intrusively investigated, and this was found to be a large boulder and tree roots. Study implications suggest careful multiphase geophysical surveys are best practice and give confidence in cold case searches. This study yielded a no‐body result, effectively saving police time and costs from further investigations. 相似文献
6.
In response to research demonstrating that irrelevant contextual information can bias forensic science analyses, authorities have increasingly urged laboratories to limit analysts' access to irrelevant and potentially biasing information (Dror and Cole (2010) [3]; National Academy of Sciences (2009) [18]; President's Council of Advisors on Science and Technology (2016) [22]; UK Forensic Science Regulator (2015) [26]). However, a great challenge in implementing this reform is determining which information is task-relevant and which is task-irrelevant. In the current study, we surveyed 183 forensic analysts to examine what they consider relevant versus irrelevant in their forensic analyses. Results revealed that analysts generally do not regard information regarding the suspect or victim as essential to their analytic tasks. However, there was significant variability among analysts within and between disciplines. Findings suggest that forensic science disciplines need to agree on what they regard as task-relevant before context management procedures can be properly implemented. The lack of consensus about what is relevant information not only leaves room for biasing information, but also reveals foundational gaps in what analysts consider crucial in forensic decision making. 相似文献
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8.
Youngmin Kim M.S. Won-sil Choi Ph.D. Byoungjun Jeon B.S. Tae Hyun Choi M.D. Ph.D. 《Journal of forensic sciences》2020,65(2):458-464
Cholesterol and squalene are fatty materials of latent fingermarks that can be utilized for dating methodologies and visualization techniques. Previous studies have suggested these compounds undergo degradation in fingermarks as a function of time (days) and light at ambient temperature. However, studies assessing how their composition changes at low and high temperatures over short periods of time (hours) have not been published previously. Here, we performed quantitative analysis of cholesterol and squalene in natural fingermark residue using PVDF membrane, after exposure to a range of temperatures (−20 to 100°C) for 4 and 8 h. We found that levels of both fatty materials remained constant at −20 to 60°C, but both showed significant reduction at 100°C, over short exposure times. These results indicate that cholesterol and squalene are detectable at −20 to 60°C, whereas at 100°C or higher, both are lost due to rapid thermal degradation. 相似文献
9.
Ayşegül Erdoğan Ph.D. Meral Esen Ph.D. Robin Simpson Ph.D. 《Journal of forensic sciences》2020,65(5):1730-1735
X-ray photoelectron spectroscopy (XPS) is a widely used technique to characterize the surface chemistry of materials. It plays a crucial role in accessing qualitative and quantitative information and in detecting the presence of chemical functional groups on the surface of any material. The forensic methods available to detect and identify elements and organic/inorganic compounds are often destructive, so evidence cannot be re-analyzed. However, XPS allows rapid analysis of samples without damaging them. Recently, an increasing number of forensic researchers have begun to study certain chemical information on fingermarks. In this study, the authors aimed to present the applicability and power of XPS imaging in fingermark analysis which can also provide specific information about the fingermark chemical composition. Herein, monochromated X-ray (Al Kα) spot size was fixed at 50 μm. XPS mapping resulted in the acquisition of spectra at each pixel, in an array of 41 × 30 pixels with a step size of 50 μm. Then, a simple discussion has been made about how the scanned surface spectrum and basic snapshot spectra are used to identify different components at a fingertip of a scanned surface area (~3 mm2). Hence, a fingermark pattern contaminated with caffeine, TiO2, and Pb/PbO deposited on the silicon wafer can be chemically mapped and visualized by XPS using principal component analysis (PCA). Thus, the present study showed the possible applicability of XPS for the identification of illicit drugs of abuse, gunshot residue, and skin care products on latent fingermark by mimicking a crime scene evidence. 相似文献
10.
学术瑕疵类、学术垄断类失范行为之所以普遍存在,与科技伦理教育观密切相关。当前,我国的科技伦理教育主要存在法治意识淡薄,忽视培养具有法治思维的科技伦理专业人才,以及缺乏法治化制度保障等问题。然而,法治思维作为社会治理的核心思维,具有将其引入科技伦理教育的必要性和可行性。为实现规制学术道德失范行为以净化科技伦理生态的道德理想,需要在科技伦理教育的过程中中融入法治思维并凸显法治作用,从而构筑起坚不可摧的法治屏障。所以,法治思维视域下科技伦理教育观的完善应从德法并重,严重的学术道德失范行为应以法律规制为主,且科技伦理教育中亟待重视法治思维的培育等方面着力;法治思维视域下,高等院校与科研机构对于科研人员科技伦理教育观的培育应从增设科技法和知识产权法课程,强化警示教育,且在对于学术道德失范行为的学术研究和立法规制等方面努力。 相似文献