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Dogs have a powerful olfactory system, which is used in many areas of the police and military to detect drugs, human remains, and explosives, among other items. Despite these powerful detection abilities, methods assessing the performance (MAP) of dogs remain scarce, and have never been validated. In particular, scientific knowledge on post-training performance assessments is scarce. To validate a quantitative MAP, an efficient detection dog (DD) must first be defined. Here, we aimed to define what an efficient DD is, and to develop a quantitative MAP. Specifically, we conducted 1) an international survey sent to professional DD practitioners (n= 50), and 2) an experimental assay on cadaver and drug DDs (n= 20). Based on the survey, efficient DDs were defined as confident animals, making few mistakes, alerting to the presence of target odors as close as possible, able to strategically screen the search area effectively, independent and not easily distracted. The developed quantitative MAP was based on video tracking DDs in a circular behavioral arena, in which the error rate of DD was recorded, including accuracy and the strategy level. Previous studies have already demonstrated that DDs are usually confidant. Guidance was not assessed during MAP development; however, handlers could not guide DDs during the search session. Based on this method, future studies should evaluate DD performance throughout the entire training process. Such monitoring would allow thresholds to be determined, allowing efficient DDs to be identified, along with the effect of certain factors on performance (e.g., dogs breed, gender, and training aids used during DD conditioning).

Female Harmonia axyridis (Coleoptera: Coccinellidae) produce a sex pheromone to attract males. In the present study, we tested two hypotheses: (i) production of sex pheromone in H. axyridis is conditioned by perception of prey in their vicinity, and (ii) virgin females invest in the production of the sex pheromone, while mated females reduce their pheromone emissions. To test the first hypothesis, newly hatched larvae were divided into three groups: those fed with Ephestia kuehniella eggs, those fed with pea aphids, and those exposed to aphid volatile cues but fed with Ephestia eggs. All females produced a pheromone blend of five-components in similar relative proportions, but with contrasting absolute quantities: Females fed with Ephestia eggs produced lower amounts of pheromone (0.5 ± 0.4 ng.female−1), compared to females fed with aphids (44.2 ± 24.4 ng.female−1). The females of the third group produced intermediate concentrations of pheromone (6.0 ± 3.2 ng.female−1). To test the second hypothesis, two groups of lady beetles were made: one group of females was placed in the presence of males, while females of the other group were not. Mated and virgin females produced statistically similar amounts of pheromone (144.1 ± 49.7 ng and 43.7 ± 24.1 ng.female−1, respectively). These results suggest that H. axyridis females initiate pheromone production upon exposure to volatile cues released by their aphids prey. Females continue to release sex pheromone after mating, probably to increase the chance of multiple mating which is known to improve egg fertility.

Waren die «französischen Jakobiner», welche die Gegner der Revolution öffentlich denunziert und manche auf die Guillotine geschickt, Straßen und Städte umbenannt, Denkmäler zerstört und einen neuen Kalender entworfen haben, die Vorläufer der «cancel culture»? Beginnen wir die Beantwortung dieser Frage damit, jene Variante unserer gegenwärtigen «cancel culture» anzuprangern, die alles Mögliche als «jakobinisch» etikettiert. Historisch bezeichnet das Wort eine nicht sehr scharf umrissene Gruppe von Revolutionären, die nach 1794 als Parteigänger von Robespierre galten und für den sogenannten terreur verantwortlich gemacht wurden.

After death, corpses undergo a complex decomposition process, during which volatile organic compounds (VOCs) are released. Several groups of organisms, including insects, use these VOCs to select their mating and feeding sites. While the presence of insects on a corpse influences the decaying process, we do not know whether insects impact on the VOC profile released by the cadaver. Using decomposing rats exposed to dipterans ( Lucilia sericata ) and/or coleopterans ( Dermestes frischii ), we assessed how the presence of insects impacted the cadaver volatilome by using dynamic sampling. As expected, the decomposition of rats in presence of insects was faster than in absence of insects. All rats went through the five decomposition stages with the exception of rats decomposing without insects. The composition of their volatile profiles differed among decomposition stages. We also found that insects do not affect the volatilome of decomposing rats, and no indicator compound could be associated to the presence of specific insect groups.

A cadaver is colonized by a wide diversity of necrophagous insects. It is well documented that Dipterans are attracted by the volatile organic compounds (VOCs) released by a corpse during the first minutes following death. Coleopterans are known to be attracted by highly decomposed cadavers, but have received less attention regarding the olfaction-based mechanisms underlying these interactions. In the present study, we impregnated gauzes with VOCs collected from each decomposition stage of dead rats: fresh, bloated, active, and advanced decay. We collected the VOCs released by the gauze and confirmed what was previously know from the literature: the decomposition stages are associated with contrasting chemical profiles. We exposed Dermestes frischii Kugelann (Coleoptera: Dermestidae) male and female antennae to the same gauzes and found that stronger electrical responses were recorded when using the smell of the advanced decay stage. Finally, we performed two choices behavioral assays. Females showed no preference for the four decomposition stages, while males were attracted by the smell associated with active and advanced decay stages. These results suggest that specific VOCs released by a decaying body guide necrophagous coleopterans to their feeding site. Whether D. frischii males release pheromones to attract females remains to be tested.

Aphids (Hemiptera: Aphididae) cause significant damage and transmit viruses to various crop plants. We aimed to evaluate how the infectious status of aphids influences their interaction with potential hosts. Two aphid (Myzus persicae and Rhopalosiphum padi) and plant (Nicotiana tabacum and Triticum aestivum) species were used. The preferences of aphids towards healthy, virus-infected (Potato Leafroll Virus (PLRV) and Barley Yellow Dwarf virus (BYDV)), and endophytic entomopathogenic fungi (EEPF)-inoculated (Beauveria bassiana and Metarhizium acridum) plants were investigated in dual-choice tests. The headspace volatiles of the different plant modalities were also sampled and analyzed. Viruliferous and non-viruliferous aphids were more attracted to EEPF-inoculated plants compared to uninoculated plants. However, viruliferous aphids were more attracted to EEPF-inoculated plants compared to virus-infected plants, while non-viruliferous insects exhibited no preference. Fungal-inoculated plants released higher amounts of aldehydes (i.e., heptanal, octanal, nonanal and decanal) compared to other plants, which might explain why viruliferous and non-viruliferous aphids were more abundant in EEPF-inoculated plants. Our study provides an interesting research perspective on how EEPF are involved in behavior of virus vector, depending on the infectious status of the latter.

The decaying process of vertebrates leads to the emission of a wide panel of volatile organic compounds (VOCs). While many studies use pigs or rats as surrogate human models, some studies have attempted to characterise the volatilome of human corpses, with very contrasting results. In this literature review, we summarise the genesis of the vertebrate cadaver volatilome, from the breakdown of macromolecules to specific VOCs. Furthermore, we list the analytical methods previously employed to collect, separate, identify and quantify human cadaveric VOCs. We describe the advantages and disadvantages of these methods. Based on previously published reports, we formulate an up-to-date directory of the VOCs identified from human cadavers. We discuss the impact of the heterogeneity of the samples, and the limitations associated with sample size and the intrinsic characteristics of the corpses that were subjected to these studies. Finally, we consider the different applications that would benefit from improving the identification of the human volatilome.

Climate change is a major environmental concern and is directly related to the increasing concentrations of greenhouse gases. The increase in concentrations of atmospheric carbon dioxide (CO2), not only affects plant growth and development, but also affects the emission of plant organic volatile compounds (VOCs). Changes in the plant odor profile may affect the plant-insect interactions, especially the behavior of herbivorous insects. In this study, we compared the foraging behavior of corn leaf aphid (Rhopalosiphum maidis) on barley (Hordeum vulgare L.) seedlings grown under contrasted CO2 concentrations. During the dual choice bioassays, the winged and wingless aphids were more attracted by the VOCs of barley seedlings cultivated under ambient CO2 concentrations (aCO2, 450 ppm) than barley seedlings cultivated under elevated CO2 concentrations (eCO2, 800 ppm), nymphs were not attracted by the VOCs of eCO2 barley seedlings. Then, volatile compositions from 14-d-old aCO2 and eCO2 barley seedlings were investigated by GC-MS. While 16 VOCs were identified from aCO2 barley seedlings, only 9 VOCs were found from eCO2 barley seedlings. At last, we discussed the potential role of these chemicals observed during choice bioassays. Our findings lay foundation for functional response of corn leaf aphid under climate change through host plant modifications.

Soil thanatochemistry, defined as the study of the chemical changes occurring during the decomposition of buried corpses, is a young and inadequately documented field of research. In this study, we aim to determine the effects of decomposition on soil physico-chemical properties by combining pedological, chemical, and volatile analyses of soils surrounding buried animals. We examined chemical and volatile changes over time occurring throughout the soil column in two common soil-texture types (sandy loam and loam). We buried dead rats and let them decompose for two months. During their excavations, we characterized the physico-chemical conditions of three soil layers above the rats and one layer below, including (1) pH, dry matter, and electrical conductivity, (2) organic carbon and total nitrogen, (3) bioavailable nutrients (K, Na, Mg, Ca, and P), and (4) volatile organic compounds. Multivariate analyses (permMANOVA) revealed that a decaying rat is associated with changes in soil chemical characteristics in both soil types. However, the observed changes were not homogenous throughout the soil columns. Conditions in soil layers nearest the cadavers changed most during decomposition. We generated a predictive model by combining chemical and volatile analyses (10 % error rate), allowing us to identify key gravesoil indicators that could be used to reveal the former existence of a buried corpse in loam and sandy loam (indicators in order of importance): organic carbon, calcium, pH, conductivity, dimethyl-disulfide, and nitrogen.

Glial fibrillary acidic protein is a recently identified rare cause of autoimmune encephalomyelitis, in which the cerebrospinal fluid shows lymphocytic pleocytosis accompanied by linear perivascular radial gadolinium enhancement in the brain. We report a 19-year-old man admitted to the intensive care unit with suspected viral meningoencephalitis. Magnetic resonance imaging showed mild encephalopathy with a reversible splenial lesion. He quickly developed a coma and acute respiratory failure. Glial fibrillary acidic protein antibodies and human parainfluenza virus were detected by cerebrospinal fluid exams. He was treated with intravenous immunoglobulin, methylprednisolone pulses, plasma exchange and then six infusions of cyclophosphamide plus two of rituximab, which resulted in a total recovery.

Quelle attitude les historiens doivent-ils adopter devant le jeu video historique ? S’appuyant tant sur leur experience personnelle que sur leur reflexion sur le lien entre medias et histoire et sur la demande sociale, les auteurs proposent une analyse centree sur le role de l’historien comme conseiller du scenario et sur la place du numerique et du jeu video dans l’enseignement de l’histoire.

Arrivera-t-on a prendre nos distances avec « La Terreur » ? Trois publications recentes invitent a revenir sur cette notion qui est au cœur de nos memoires et de notre culture, et a lui faire perdre son mystere. La question est plus importante qu’il n’y parait, n’etant ni simplement erudite voire anecdotique, ni reservee aux specialistes de la Revolution francaise. La Terreur est un terme entre dans l’histoire mondiale, meme dans la philosophie de l’histoire, pour comprendre le sens de l’Histoire et qualifier des evenements survenus sur toute la planete. L’etude de « la Terreur » est donc un cas d’ecole exceptionnel qui fait reflechir sur l’ecriture meme de l’histoire, a sa naissance.

« L’histoire ne va pas de soi ». Cette formule, de l’historien polono-francais Krzysztof Pomian, aussi simple soit-elle, donne la tonalite de ce dossier n° 69 de la Revue internationale d’education de Sevres qui presente, a travers dix etudes de cas, les modalites et les difficultes rencontrees pour bâtir l’enseignement de l’Histoire. Soulignons d’emblee que le mot meme « histoire » demeure toujours problematique en francais, designant tout a la fois le recit, la discipline scientifique, les ...

La mise en ligne de la collection Baudouin constitue un evenement dont l’importance doit etre relevee. Presentee au cours d’un colloque international en septembre 2013 aux Archives nationales, cette edition numerique donne aux chercheurs la possibilite de suivre au jour le jour les 20 000 lois, decrets, proclamations adoptes ou discutes par les assemblees de la periode revolutionnaire entre 1789 et 1795, tels qu’ils ont ete publies par Francois-Jean Baudouin (1759-1835) l’imprimeur officiel d...