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With the aim of providing better control of shooting experiments performed with replicas of prehistoric projectiles, we have conducted an instrumental archaeology study on the efficiency of prehistoric projectile points by placing emphasis on their adhesion and ballistic characteristics. In order to avoid any reproducibility problems, hafting adhesives were made with controlled mixtures of commercial rosin (also called 'colophany') and beeswax added as a plasticizer. An original experimental device has been developed to instrument a bow, allowing the control of both the trajectories and the velocities of the different shoots. In the course of an experimental programme on Sauveterrian microliths from the Mesolithic period of the South of France, the experimental system was applied to composite replica projectile tips of Mesolithic hunters. Arrows being shot at transparent targets were filmed in order to evaluate the penetration length and residual damage. Interestingly, this study reveals that the properties of the mixture are highly dependent on the velocity of the arrows. It was shown that-contrary to previous experiments that usually used a mixture in which rosin predominates- the most efficient adhesive is made of 70 wt% beeswax with only 30 wt% rosin. This result is of great importance for improving further shooting experiments and overcoming the problems frequently mentioned due to the loss of the flint armatures before they reach the animal target, or at least before penetration. When using this appropriate mixture, the lateral armatures are resistant to most of the shots. Experiments performed on real boars' flesh have also shown that the presence of lateral microliths allows the laceration inflicted on the target to be enlarged. Finally, a critical parameter has been identified, which is the location on the arrow of the microlithic element. [ABSTRACT FROM AUTHOR]

Blends of rosin and beeswax were studied in terms of their thermal and mechanical behaviors. Their glass transition and α relaxation were both characterized, either by differential scanning calorimetry or by dynamic mechanical thermal analysis. In this study, we focused particularly on the impact of the microstructure on the mechanical properties, as studied by compression, shear, and nanoindentation tests. It is shown that at room temperature, these blends exhibited a viscous behavior in both the elastic and plastic regimes. From these measurements, a superplastic behavior was highlighted for blends with more than 60 wt % rosin. This superplastic behavior constitutes a real new potential in the mechanical reliability of adhesives based on rosin, which are more generally known for their very brittle behavior. As a result, it should open the way for the design of new shapes. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

The article discusses a study which evaluated the response to Berkovich indents of tetragonal and cubic phases in terms of hydrothermal degradation by using nonoindentation techniques, atomic force microscopy and Focused Ion Beam. Yttria-doped zirconia ceramics possess mechanical properties, such as strength and fracture toughness, which arise from the submicron average grain size. Results showed that microcracking is the primary reason of the drop in mechanical properties.

Electron beam-physical vapour deposited (EB-PVD) yttria-stabilized zirconia (YSZ) thermal barrier coatings have been investigated by nanoindentation. It is shown that the mechanical properties, and particularly the Young's modulus, of these coatings are closely related to their columnar microstructure. The transition from intracolumnar to intercolumnar deformation is characterized by a difference between the mechanical properties of the bulk YSZ and those of the coatings. The use of different indenter shape showed that the contact area was the parameter characteristic of this scale dependence. Deformation mechanisms studied by AFM have shown a good correlation with the evolution of the mechanical properties during the deformation. [ABSTRACT FROM AUTHOR]

This study investigates the incipient plasticity during a nanoindentation test with a spherical indenter in magnesium oxide single crystals. The load–displacement curves show multiple pop-ins, interspaced by elastic deformation, and reveal the transition from an initial elastic deformation regime to a continuous elastoplastic one. Nanoindentations have been stopped after the first pop-in and the dislocation structures have been three-dimensionally characterized by AFM observations of the surface deformation and by nanoetching. The dislocation pattern shows two activated slip systems. The resolved shear stress has been calculated just before the pop-in, for all of the activated slip systems. The final positions of the dislocations generated during the first pop-in reveal that they were all nucleated at the point of maximum resolved shear stress. [ABSTRACT FROM AUTHOR]

The instrumented indentation response of polycrystalline alumina and alumina-based ceramic multilayers with well-known residual stresses is investigated. Young's modulus and hardness were evaluated as a function of penetration depth with Berkovich and spherical indenters by continuous stiffness measurements. A size effect was observed due to the length scale of the microstructure. Values of hardness and Young's modulus were in good agreement with previous works. No significant differences in the P – h curves were observed for materials with and without residual stress, making it difficult to employ the various methodologies in the literature for estimation of residual stress or crack length evaluation. Crack length had, therefore, to be measured by direct observation. Thus, cube corner indentations did not produce well-developed radial cracks but chipping of the material, whereas indentations with Berkovich indenters produced radial cracks suitable for apparent fracture toughness estimation and, consequently, residual stress. [ABSTRACT FROM AUTHOR]

This letter is based on recent progress in the observation of dislocation distributions around nanoindentations by chemical etching. This so-called nanoetching technique is used to determine the dislocation mechanisms associated with the pop-in phenomenon in MgO and LiF. Successive stages of highly controlled chemomechanical polishing have revealed that these dislocations are half-loops lying in the classical slip systems of MgO or LiF. However, they do not extend on the surface in the classical rosette-arms pattern but stay concentrated around the imprint. A mechanism of dislocation interactions, enhanced by the fact that the dislocations are suddenly nucleated in a small volume, is proposed to explain this specific distribution. [ABSTRACT FROM AUTHOR]

Despite prevention efforts, many cases of mushroom poisoning are reported around the world every year. Among the different toxins implicated in these poisonings, muscarine may induce parasympathetic neurological damage. Muscarine poisonings are poorly reported in the current literature, implying a lack of available data on muscarine concentrations in human matrices. A validated liquid chromatography with high-resolution mass spectrometry detection (Orbitrap technology) method was developed to determine muscarine concentrations in human urine, plasma, and whole blood samples. Muscarine was determined using 100 μL of biological fluids, and precipitation was used for sample preparation. Liquid chromatography-mass spectrometry was performed using an Accucore Phenyl-X analytical column with the electrospray source in positive ion mode. Muscarine was quantitated in parallel reaction monitoring (PRM) mode with D9-muscarine as the internal standard. The method was validated successfully over the concentration range 0.1-100 μg/L for plasma and whole blood and 1-100 μg/L for urine, with acceptable precision and accuracy (<13.5%), including the lower limit of quantification. Ten real cases of suspected muscarine poisoning were successfully confirmed with this validated method. Muscarine concentrations in these cases ranged from 0.12 to 14 μg/L in whole blood,

Drug facilitated-crime or chemical submission (DFC/CS) is defined as the concealed or forced administration of psychoactive substances to a victim for criminal purposes. This is a national program set up in the early 2000 s in the form of a prospective multicenter survey, the results of which this manuscript presents. Over this 19-year period, 5487 cases were collected, analyzed and classified into 54 % of suspected cases, 29 % of chemical vulnerability (CV) cases and 17 % of proven DFC/CS cases. In the overall data, the most prevalent victims were female (81 %), with an average age of 27 years. Sexual assault was the most frequent aggression (77 %), followed by theft (14 %). Victims of proven DFC/CS cases were from of all ages including children and elderly. In 934 victims of DFC/CS, 100 various psychoactive substances were detected mostly represented by benzodiazepines and z-drugs (55 %), various sedatives including antihistamines (16 %) and non-therapeutic substances (16 %). Gamma-hydroxybutyric acid (GHB) was found in 4 % cases. In CV cases, alcohol (90 %) and cannabis (32 %) intake were mainly involved. In France, despite prevention messages, DFC/CS has been an epidemic for many years and has been proven by our national study. This national program has the aim to identifying the substances used but unfortunately not the goal to fight against this phenomenon. Since 2009, we observed a new modus operandi of the aggressors who pose as taxi drivers facilitating the reception of the victims leaving nightclubs. We can emphasize that GHB is not the "date rape drug" but rather the benzodiazepine class is., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Consumption of mushrooms can become unsafe for the consumer in case of confusion. Some fungi of Cortinarius genus contain the nephrotoxic mycotoxin orellanine responsible for their toxicity. Related case poisoning diagnosis is a challenge for both clinicians and analysts because of a long latency period between intake and toxic syndrome, the lack of available information in literature and the numerous pitfalls of orellanine identification/quantification in biological samples. In this situation, we propose an analytical method designed for the orellanine detection and/or quantification in biological matrices such as plasma, urine and whole blood, in a context of related intoxication suspected case. Using 1 mL biological sample volume, this liquid chromatographic with high-resolution mass spectrometry detection method (i) exhibits a limit of quantification for orellanine of 0.5 µg/L in plasma and urine and (ii) enables orellanine detection in whole blood with a limit of detection of 0.5 µg/L. This validated analytical method was successfully applied to 10 suspected intoxication cases., (© The Author(s) 2022. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Several families of higher fungi contain mycotoxins that cause serious or even fatal poisoning when consumed by humans. The aim of this review is to inventory, from an analytical point of view, poisoning cases linked with certain significantly toxic mycotoxins: orellanine, α- and β-amanitin, muscarine, ibotenic acid and muscimol, and gyromitrin. Clinicians are calling for the cases to be documented by toxicological analysis. This document is therefore a review of poisoning cases involving these mycotoxins reported in the literature and carries out an inventory of the analytical techniques available for their identification and quantification. It seems indeed that these poisonings are only rarely documented by toxicological analysis, due mainly to a lack of analytical methods in biological matrices. There are many reasons for this issue: the numerous varieties of mushroom involved, mycotoxins with different chemical structures, a lack of knowledge about distribution and metabolism. To sum up, we are faced with (i) obstacles to the documentation and interpretation of fatal (or non-fatal) poisoning cases and (ii) a real need for analytical methods of identifying and quantifying these mycotoxins (and their metabolites) in biological matrices.

Today, new psychoactive substances (NPS) producers increasingly appear to be targeting new synthetic opioids (NSOs), and the recent emergence of NSOs is causing considerable concern in North America and in Europe. For toxicologists, NSO detection in a forensic context presents three additional difficulties to the general NPS analytical detection challenge: (i) high frequency of new products, (ii) low concentrations (in μg/L range and under) in biological samples related to their high opioid potency, and (iii) extensive metabolism. In this context, the present work aims to highlight the relevance of NSO metabolite detection in potential intoxication cases. Illustration is given with U-47700, an emerging NSO, (i) that was identified in a powder recently collected in France and in a fatality case, (ii) whose metabolites were in vitro produced using human liver microsomes and their mass spectra (MS) added in our MS/MS and HRMS libraries, and (iii) for which metabolism data were compared to those of the literature: U-47700 was identified in the powder and at 3040 μg/L in peripheral blood in the fatality case. In addition, high amounts of several U-47700 metabolites, especially N-desmethyl-U-47700, were observed in urine. Even if metabolite formation may largely depend on the enzymatic activity as well as on the length of the survival time, confrontation of these results to data found in the literature strongly suggests that this metabolite is regularly a better blood and (mainly) urine biomarker of U-47700 intake than U-47700 itself. Indeed, in this fatality and in other previous reports, N-desmethyl-U-47700 produced the main observed chromatographic signal (i) systematically in vitro and (ii) commonly in vivo, especially in urines. N,N-Didesmethyl-U-47700 is also sometimes a better biomarker of U-47700 intake than U-47700 itself. Accordingly, we suggest adding N-desmethyl-U-47700 (and N,N-didesmethyl-U-47700) in mass spectrum databases used for toxicological screening in order to reduce the risk of false-negative results in intoxication cases involving U-47700.

Rubber bullets weapons can have tragic consequences when used at short range and on vulnerable body areas. A man in his forties was found deceased at his house, covered in blood. A "non-lethal" firearm was found near the bed: the «SAPL GC27». This is a single shot handgun with mini Gomm Cogne ammunition: 12 rubber spherical pellets, 7.4 mm in diameter. The findings were consistent with an intra buccal shot, and an ingestion-inhalation of blood and projectiles. Cause of the death was linked to both the hemorrhage due to mouth and aero digestive crossroad trauma, responsible of a mechanical asphyxia, and blood absorption in lungs. This case insists on the deadly potential of this weapon if misused. Fortunately, the term "non-lethal" has been progressively replaced, but sometimes still can be seen, especially in gunsmith and webstores. It should be deleted to avoid confusion among inexperienced people, and at best, this weapon should be restricted to certain professions., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The ready availability of butane makes butane abuse frequent. Fatalities are rare. This study presents two cases of death by butane overdose. The postmortem analyses were carried out using headspace gas chromatography-mass spectrometry. It revealed femoral blood butane concentrations of 18 and 22 mg/L, respectively, as well as specific combinations of adjuvants in each victim. In one of the victims, brain and fatty tissue also contained butane, pointing to chronic consumption. The originality of this study is to show that the identification of specific combinations of adjuvants can be helpful for identifying the brand of deodorant used. Also, sampling the skin and mucosa can help identify the method of drug delivery. The histological examination documented both the direct toxic effect of the gas on the respiratory mucosa and signs of chronic abuse. Volatile substance intoxications should be systematically considered in case of sudden death in a teenager., (© 2017 American Academy of Forensic Sciences.)

We report the case of a child succumbing to heatstroke caused by confinement in an icebox. The post mortem examination found cyanosis and hematomas indicating that the child had tried to get out of the container. The temperature of the body was higher than it should have been considering the rigor and delay before post mortem examination. The autopsy showed no significant injury and toxicological tests were negative. A physiological study etablished that death resulted from heatstroke, not a lack of oxygen or CO2 poisoning. We conclude that heat stroke should be considered as a possible mechanism of death even in the absence of context of environmental hyperthermia. We recommend that in these situations involving confinement, establishing the mechanism of death should be done not only on the basis of a detailed post-mortem examination to rule out other causes of death, but also based on complete physiological investigations., (Copyright © 2015 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.)

Background: Hypoglycin A has been recently identified has the causal agent of atypical myopathy (AM) in horses. Its identification and quantification in equine's biological fluids is thus a major concern to confirm maple poisoning and to provide insight into the poorly understood mechanism of hypoglycin A intoxication., Methods: Quantification of hypoglycin A has been achieved with the aTRAQ kit for amino acid analysis of physiological fluids (AB Sciex). Acquisition method on mass spectrometer has been updated to record the hypoglycin A specific MRM transition., Results: Outlined accuracy profiles demonstrated very reliable data. A good linearity was observed from 0.09 to 50μmol/L and precision was very good with coefficient of variation below 8%. Fifty-five samples collected from 25 confirmed AM horses revealed significant hypoglycin A concentrations, while toxin was not found in serum of 8 control animals., Conclusions: The described aTRAQ variant method has been analytically and clinically validated. The reliability of our approach is thus demonstrated into the workup of atypical myopathy., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Hypoglycin A (HGA) is the toxic principle in ackee (Blighia sapida Koenig), a nutritious and readily available fruit which is a staple of the Jamaican working-class and rural population. The aril of the unripe fruit has high concentrations of HGA, the cause of Jamaican vomiting sickness, which is very often fatal. HGA is also present in the samara of several species of maple (Acer spp.) which are suspected to cause seasonal pasture myopathy in North America and equine atypical myopathy in Europe, often fatal for horses. The aim of this study was to develop a method for quantifying HGA in blood that would be sensitive enough to provide toxicological evidence of ackee or maple poisoning. Analysis was carried out using solid-phase extraction (HILIC cartridges), dansyl derivatization and UHPLC-HRMS/MS detection. The method was validated in whole blood with a detection limit of 0.35 μg/L (range: 0.8-500 μg/L). This is the first method applicable in forensic toxicology for quantifying HGA in whole blood. HGA was quantified in two serum samples from horses suffering from atypical myopathy. The concentrations were 446.9 and 87.8 μg/L. HGA was also quantified in dried arils of unripe ackee fruit (Suriname) and seeds of sycamore maple (Acer pseudoplatanus L.) (France). The concentrations were 7.2 and 0.74 mg/g respectively., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Plant poisonings have left their mark on history and still cause many deaths, whether intentional or accidental. The means to show toxicological evidence of such poisonings should be implemented with great care. This article presents a technique for measuring thirty-nine toxic principles of plant origin in the blood, covering a large amount of toxins from local or exotic plants: α-lobeline, α-solanine, aconitine, ajmaline, atropine, brucine, cephalomannine, colchicine, convallatoxin, cymarine, cytisine, digitoxin, digoxin, emetine, gelsemine, ibogaine, jervine, kavain, lanatoside C, lupanine, mitragynine, neriifolin, oleandrin, ouabain, paclitaxel, physostigmine, pilocarpine, podophyllotoxin, proscillaridin A, reserpine, retrorsine, ricinine, scopolamine, senecionine, sparteine, strophanthidin, strychnine, veratridine and yohimbine. Analysis was carried out using an original ultra-high performance liquid chromatography separation coupled with tandem mass spectrometry detection. Extraction was a standard solid phase extraction performed on Oasis(®) HLB cartridge. Thirty-four of the thirty-nine compounds were put through a validation procedure. The assay was linear in the calibration curve range from 0.5 or 5 μg/L to 1000 μg/L according to the compounds. The method is sensitive (LOD from 0.1 to 1.6 μg/L). The within-day precision of the assay was less than 22.5% at the LLOQ, and the between-day precision was less than 21.5% for 10 μg/L for all the compounds included. The assay accuracy was in the range of 87.4 to 119.8% for the LLOQ. The extraction recovery and matrix effect ranged from 30 to 106% and from -30 to 14%, respectively. It has proven useful and effective in several difficult forensic cases., (Copyright © 2014 Elsevier B.V. All rights reserved.)