Study of isotopic variations in black powder: reflections on the use of stable isotopes in forensic science for source inference.

Isotope ratio mass spectrometry (IRMS) has recently made its appearance in the forensic community. This high-precision technology has already been applied to a broad range of forensic fields such as illicit drugs, explosives and flammable liquids, where current, routinely used techniques have limited powers of discrimination. The conclusions drawn from the majority of these IRMS studies appear to be very promising. Used in a comparative process, as in food or drug authentication, the measurement of stable isotope ratios is a new and remarkable analytical tool for the discrimination or the identification of a substance with a definite source or origin. However, the research consists mostly of preliminary studies. The significance of this 'new' piece of information needs to be evaluated in light of a forensic framework to assess the actual potential and validity of IRMS, considering the characteristics of each field. Through the isotopic study of black powder, this paper aims at illustrating the potential of the method and the limitations of current knowledge in stable isotopes when facing forensic problems.

Electrical source imaging for presurgical focus localization in epilepsy patients with normal MRI.

PURPOSE: Patients with magnetic resonance (MR)-negative focal epilepsy (MRN-E) have less favorable surgical outcomes (between 40% and 70%) compared to those in whom an MRI lesion guides the site of surgical intervention (60-90%). Patients with extratemporal MRN-E have the worst outcome (around 50% chance of seizure freedom). We studied whether electroencephalography (EEG) source imaging (ESI) of interictal epileptic activity can contribute to the identification of the epileptic focus in patients with normal MRI. METHODS: We carried out ESI in 10 operated patients with nonlesional MRI and a postsurgical follow-up of at least 1 year. Five of the 10 patients had extratemporal lobe epilepsy. Evaluation comprised surface and intracranial EEG monitoring of ictal and interictal events, structural MRI, [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET), ictal and interictal perfusion single photon emission computed tomography (SPECT) scans. Eight of the 10 patients also underwent intracranial monitoring. RESULTS: ESI correctly localized the epileptic focus within the resection margins in 8 of 10 patients, 9 of whom experienced favorable postsurgical outcomes. DISCUSSION: The results highlight the diagnostic value of ESI and encourage broadening its application to patients with MRN-E. If the surface EEG contains fairly localized spikes, ESI contributes to the presurgical decision process.

Ignition of a human body by a modest external source: a case report.

A case of sustained combustion of a human body that occurred in 2006 in Geneva, Switzerland, is presented. The body of a man was discovered at home and found to have been almost completely incinerated between the knees and the mid-chest, with less damage to the head, arms, lower legs and feet. His dog was also found dead just behind the house door. The external source of ignition was most likely a cigarette or a cigar. The chair in which the man had been sitting was largely consumed while other objects in the room exhibited only a brown oily or greasy coating and were virtually undamaged. Toxicological analyses carried out on the blood from the lower legs showed low levels of desalkylflurazepam. Alcohol concentration was 1.10 per thousand, carboxyhaemoglobin levels were 12% and cyanide concentration was 0.05 mg/L. Toxicological analyses carried out on the dog's blood showed carboxyhaemoglobin levels at 65%.

Isotope ratio mass spectrometry as a tool for source inference in forensic science: a critical review

Isotope ratio mass spectrometry (IRMS) has been used in numerous fields of forensic science in a source inference perspective. This review compiles the studies published on the application of isotope ratio mass spectrometry (IRMS) to the traditional fields of forensic science so far. It completes the review of Benson et al. [1] and synthesises the extent of knowledge already gathered in the following fields: illicit drugs, flammable liquids, human provenancing, microtraces, explosives and other specific materials (packaging tapes, safety matches, plastics, etc.). For each field, a discussion assesses the state of science and highlights the relevance of the information in a forensic context. Through the different discussions which mark out the review, the potential and limitations of IRMS, as well as the needs and challenges of future studies are emphasized. The paper elicits the various dimensions of the source which can be obtained from the isotope information and demonstrates the transversal nature of IRMS as a tool for source inference.

Les codes de l'obligations : méta-analyses pragmatologiques de l'application de méthodes en sciences sociales

Cette thèse rassemble une série de méta-analyses, c'est-à-dire d'analyses ayant pour objet des analyses produites par des sociologues (notamment celles résultant de l'application de méthodes de traitement des entretiens). Il s'agit d'une démarche réflexive visant les pratiques concrètes des sociologues. Celles-ci sont envisagées comme des activités gouvernées par des règles. Une part importante de cette thèse sera donc consacrée au développement d'un outil d'analyse « pragmatologique » (E. Durkheim), c'est-à-dire permettant l'étude des pratiques et des règles en rapport avec elles. Pour aborder les règles, la philosophie analytique d'inspiration wittgensteinienne apporte plusieurs propositions importantes. Les règles sont ainsi considérées comme des concepts d'air de famille : il n'y a pas de définitions communes recouvrant l'ensemble des règles. Pour étudier les règles, il convient alors de faire des distinctions à partir de leurs usages. Une de ces distinctions concerne la différence entre règles constitutives et règles régulatives : une règle constitutive crée une pratique (e.g. le mariage), alors qu'une règle régulative s'applique à des activités qui peuvent exister sans elle (e.g. les règles du savoir-vivre). L'activité méthodologique des sociologues repose et est contrainte par ces types de règles, qui sont pour l'essentiel implicites. Cette thèse vise donc à rendre compte, par la description et la codification des règles, du caractère normatif des méthodes dans les pratiques d'analyse de la sociologie. Elle insiste en particulier sur les limites logiques qu'instituent les règles constitutives, celles-ci rendant impossibles (et non pas interdites) certaines actions des sociologues. This thesis brings together a series of meta-analyzes, that is, analyzes that tackle analyzes produced by sociologists (notably those resulting from the application of methods in treating interviews). The approach is reflexive and aimed at the concrete practices of sociologists, considered as activities governed by rules. An important part of this thesis is therefore devoted to the development of a "pragmatological" analytical tool (Durkheim) to conduct a study of such practices and of the rules that govern them. To approach these rules, Wittgenstein-inspired analytic philosophy offers several important proposals. The rules are, at first, seen as concepts of family resemblance, assuming that there is no common definition accounting for all rules. In order to conduct the study of such rules, it is therefore necessary to discern how they are respectively used. One of these distinctions concerns the difference between constitutive rules and regulative rules: a constitutive rule creates a practice (for example marriage), while a regulative rule applies to activities that can exist outside of the rule (for example, the rules of etiquette). The methodological activity of sociologists relies on, and is constrained by these types of rules, which are essentially implicit. Through the description and codification of rules, this thesis aims to account for the normative character of methods governing analytical practices in sociology. Particular emphasis is on the logical limits established by constitutive rules, limits that render several of the sociologist's actions impossible (rather than forbidden).

Embolic Strokes of Undetermined Source in the Athens Stroke Registry: an Outcome Analysis.

BACKGROUND AND PURPOSE: Information about outcomes in Embolic Stroke of Undetermined Source (ESUS) patients is unavailable. This study provides a detailed analysis of outcomes of a large ESUS population. METHODS: Data set was derived from the Athens Stroke Registry. ESUS was defined according to the Cryptogenic Stroke/ESUS International Working Group criteria. End points were mortality, stroke recurrence, functional outcome, and a composite cardiovascular end point comprising recurrent stroke, myocardial infarction, aortic aneurysm rupture, systemic embolism, or sudden cardiac death. We performed Kaplan-Meier analyses to estimate cumulative probabilities of outcomes by stroke type and Cox-regression to investigate whether stroke type was outcome predictor. RESULTS: 2731 patients were followed-up for a mean of 30.5±24.1months. There were 73 (26.5%) deaths, 60 (21.8%) recurrences, and 78 (28.4%) composite cardiovascular end points in the 275 ESUS patients. The cumulative probability of survival in ESUS was 65.6% (95% confidence intervals [CI], 58.9%-72.2%), significantly higher compared with cardioembolic stroke (38.8%, 95% CI, 34.9%-42.7%). The cumulative probability of stroke recurrence in ESUS was 29.0% (95% CI, 22.3%-35.7%), similar to cardioembolic strokes (26.8%, 95% CI, 22.1%-31.5%), but significantly higher compared with all types of noncardioembolic stroke. One hundred seventy-two (62.5%) ESUS patients had favorable functional outcome compared with 280 (32.2%) in cardioembolic and 303 (60.9%) in large-artery atherosclerotic. ESUS patients had similar risk of composite cardiovascular end point as all other stroke types, with the exception of lacunar strokes, which had significantly lower risk (adjusted hazard ratio, 0.70 [95% CI, 0.52-0.94]). CONCLUSIONS: Long-term mortality risk in ESUS is lower compared with cardioembolic strokes, despite similar rates of recurrence and composite cardiovascular end point. Recurrent stroke risk is higher in ESUS than in noncardioembolic strokes.

Avancées sur la source, la taille et la nature des particules microbiennes aéroportées présentes dans l'environnement intérieur

L'exposition à certaines particules fongiques et bactéries présentes dans les aérosols de l'environnement intérieur a été associée au développement ou à l'exacerbation d'affections respiratoires telles que l'asthme, la rhinite allergique ou encore l'aspergillose (1-4). Le réservoir principal identifié dans cet environnement pour les bactéries aéroportées est constitué par les habitants eux-mêmes, alors que celui des particules fongiques est l'environnement extérieur, ou, lorsque les conditions sont réunies, l'environnement intérieur (5-7). Néanmoins, la nature et la taille de ces particules fongiques, ainsi que l'impact de l'occupation humaine sur ces paramètres n'ont été que peu explorés. Les articles de cette note s'intéressent justement à ces aspects et illustrent l'importance de leur prise en compte dans l'évaluation du risque d'exposition aux microorganismes dans l'environnement intérieur. L'étude de Hospodsky et coll. (2014) apporte une information quantitative sur le niveau d'émission de bactéries et particules fongiques résultant d'une occupation humaine dans des environnements intérieurs sains. Alors que l'étude de Afanou et coll. (2014) montre la complexité des particules fongiques qui peuvent être générées dans l'environnement intérieur, différentes espèces de moisissures pouvant participer en proportions différentes au nombre de particules submicroniques1 grâce à leurs fragments de spores ou hyphes.