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81.
Headspace solid-phase microextraction (HS-SPME) is assessed as an alternative to liquid-liquid extraction (LLE) currently used for 3,4-methylenedioxymethampethamine (MDMA) profiling. Both methods were compared evaluating their performance in discriminating and classifying samples. For this purpose 62 different seizures were analysed using both extraction techniques followed by gas chromatography-mass spectroscopy (GC-MS). A previously validated method provided data for HS-SPME, whereas LLE data were collected applying a harmonized methodology developed and used in the European project CHAMP. After suitable pre-treatment, similarities between sample pairs were studied using the Pearson correlation. Both methods enable to distinguish between samples coming from the same pre-tabletting batches and samples coming from different pre-tabletting batches. This finding emphasizes the use of HS-SPME as an effective alternative to LLE, with additional advantages such as sample preparation and a solvent-free process. 相似文献
82.
Federica Gregoratto 《Critical Horizons》2018,19(1):18-34
The paper sketches out an account of ambiguous and agonistic love by drawing on the work of Simone de Beauvoir, Axel Honneth and Hannah Arendt. To begin with, I reconstruct the ambiguity of love within the conceptual framework of a paradigm of recognition. I argue further that the social relation of love, understood as an intertwine between dependence and independence, entails a power dynamic. Insofar as the dynamic actualises as “power in concert” or “power with”, namely as mutual empowerment, love unfolds as free love. Finally, I show how agonistic love is damaged by turning into violent domination. 相似文献
83.
Previous research has established a relationship between income and food security. In this article, we examine the effect of food security on food purchases, specifically on five food‐at‐home groups. Using a set of Tobit models, and after controlling for a set of confounding factors, we show that food security perception leads to the purchase of fruit and vegetables, meats and eggs, and dairy products while decreasing the purchase of fat and carbohydrates. However, we cannot be certain of the actual nutritional effect. 相似文献
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86.
Paolo Gubitta Alessandra Tognazzo Federica Destro 《The Journal of Technology Transfer》2016,41(2):368-393
University spinoffs, an important subset of high-tech start-up companies, operate in a context characterized by marked information asymmetries that limit their chances of obtaining financing. Given the uncertainty and imperfect information that characterize these investment opportunities, signals about their potential value deserve further attention. We investigate the relationship between the main stakeholders involved in the process of creating a university spinoff—that is, the academic founders, the university technology-transfer office, and private investors—focusing on the role of public grants as effective signals that attract private venture capital (VC) funding. Using the database of all spinoff companies established to exploit inventions assigned to the University of Michigan from 1999 to 2010, we determine how the funds provided through the university technology-transfer office influence VC follow-on funding and consequent spinoff growth, controlling for the spinoff’s technology, the founders’ human capital, and the network’s resources. The empirical results support a signaling effect of the commercialization funds provided by the university and suggest an indirect impact on the growth of the spinoff’s sales through the mediating effect of VC financing. 相似文献
87.
Martina Focardi M.D. Aurelio Bonelli M.D. Vilma Pinchi D.D.S. Ph.D. Federica De Luca M.D. Gian‐Aristide Norelli M.D. 《Journal of forensic sciences》2016,61(Z1):S252-S255
Pulmonary polymethylmethacrylate (PMMA) cement embolism after kyphoplasty (KP) surgery is a quite frequent event as well as the pulmonary embolization of central venous catheter fragment. This report shows the case of a subject who, after KP, developed pulmonary embolism and who underwent thoracic surgery. After hospital discharge, the subject advanced a claim for damages toward the hospital where he was operated, complaining sensation of tenderness at the chest surgical scar and esthetic damage. To understand the nature of the embolism (either central venous catheter fragment or cement), chemical investigations were then ordered. Spectrometry identified the PMMA cement used for KP. When doubts rise about the origin of the embolized material, chemical investigations may reveal important data not only for clinical but also for forensic purposes. 相似文献
88.
Multivariate Classification of Original and Fake Perfumes by Ion Analysis and Ethanol Content
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Clêrton L. Gomes Ph.D. Ari Clecius A. de Lima M.S. Adonay R. Loiola Ph.D. Abel B. R. da Silva M.S. Manuela C. L. Cândido M.S. Ronaldo F. Nascimento Ph.D. 《Journal of forensic sciences》2016,61(4):1074-1079
The increased marketing of fake perfumes has encouraged us to investigate how to identify such products by their chemical characteristics and multivariate analysis. The aim of this study was to present an alternative approach to distinguish original from fake perfumes by means of the investigation of sodium, potassium, chloride ions, and ethanol contents by chemometric tools. For this, 50 perfumes were used (25 original and 25 counterfeit) for the analysis of ions (ion chromatography) and ethanol (gas chromatography). The results demonstrated that the fake perfume had low levels of ethanol and high levels of chloride compared to the original product. The data were treated by chemometric tools such as principal component analysis and linear discriminant analysis. This study proved that the analysis of ethanol is an effective method of distinguishing original from the fake products, and it may potentially be used to assist legal authorities in such cases. 相似文献
89.
Ana Claudia Martins Ciconelle BSc MSc Renan Lucio Berbel da Silva DDS MSc Jun Ho Kim DDS MSc PhD Bruno Aragão Rocha MD Dênis Gonçalves dos Santos BSc Luis Gustavo Rocha Vianna BSc MSc Luma Gallacio Gomes Ferreira BSc Vinícius Henrique Pereira dos Santos Jeferson Orofino Costa DDS Renato Vicente BSc MSc PhD 《Journal of forensic sciences》2023,68(6):2057-2064
The objective of this study is to assess the performance of an innovative AI-powered tool for sex determination using panoramic radiographs (PR) and to explore factors affecting the performance of the convolutional neural network (CNN). The study involved 207,946 panoramic dental X-rays and their corresponding reports from 15 clinical centers in São Paulo, Brazil. The PRs were acquired with four different devices, and 58% of the patients were female. Data preprocessing included anonymizing the exams, extracting pertinent information from the reports, such as sex, age, type of dentition, and number of missing teeth, and organizing the data into a PostgreSQL database. Two neural network architectures, a standard CNN and a ResNet, were utilized for sex classification, with both undergoing hyperparameter tuning and cross-validation to ensure optimal performance. The CNN model achieved 95.02% accuracy in sex estimation, with image resolution being a significant influencing factor. The ResNet model attained over 86% accuracy in subjects older than 6 years and over 96% in those over 16 years. The algorithm performed better on female images, and the area under the curve (AUC) exceeded 96% for most age groups, except the youngest. Accuracy values were also assessed for different dentition types (deciduous, mixed, and permanent) and missing teeth. This study demonstrates the effectiveness of an AI-driven tool for sex determination using PR and emphasizes the role of image resolution, age, and sex in determining the algorithm's performance. 相似文献
90.
Allelic frequencies, forensic parameters and admixture values for eleven STR loci (F13B, TPOX, CSF1PO, F13A01, D7S820, LPL, TH01, vWA, D13S317, FESFPS, and D16S539) were determined in a sample of unrelated individuals, European descendants from Rio de Janeiro area, Brazil. 相似文献