Electrical discharges in water are a subject of major interest because of both the wide range of potential applications and the complexity of the processes. This paper aimed to provide significant ...insights to better understand processes involved during a microsecond electrical discharge in water, especially during the propagation and the breakdown phases. Two different approaches were considered. The first analysis focused on the emission produced by the discharge during the propagation using fast imaging measurements and spatially resolved optical emission spectroscopy. The excited species H, O, and OH were monitored in the whole interelectrode gap. The second analysis concerned the thermodynamic conditions induced by the breakdown of the discharge. The time evolution of the bubble radius was simulated and estimation of the initial pressure of the cavitation bubble was performed using the Rayleigh-Plesset model. Values of about 1.7 × 10
Pa and 1.2 × 10
Pa were reported for the cathode and anode regimes, respectively. This multidisciplinary approach constitutes a new step to obtain an accurate physical and chemical description of pin-to-pin electrical discharges in water.
Paleoparasitology is a discipline of bioarchaeology that studies human and animal parasites and their evolution through time. It is at the frontier between biological sciences and the humanities, and ...aims to provide valuable clues about the lifestyles of former populations. Through examples chosen among recent case studies, we show in this review how paleoparasitology contributes to issues related to food, health, hygiene, organic waste management, and site occupation by ancient populations, but also, in the longer term, to questions of the evolution of the human/animal relationship and the history of diseases. This article provides an overview of this research field, its history, its concepts, and in particular, its applications in archaeology and the history of diseases.
Paleoparasitological investigations revealed the presence of intestinal helminths in samples taken from the abdominal cavities of two German soldiers, recovered in the First World War site named ..."Kilianstollen" in Carspach, France. Eggs from roundworm, whipworm, tapeworm and capillariids were identified. The morphological and morphometrical comparison, followed by statistical analyses, showed that the Carspach capillariid eggs are similar to rodent parasites. Poor sanitary conditions in the trenches, the lack of knowledge of parasites, and the widespread presence of commensal animals, can explain the occurrence of such parasites in human intestines. This study is the second dealing with 20th century human samples. It confirms the presence of intestinal worms in First World War German soldiers. In this case study, the application of statistics to precise measurements facilitated the diagnosis of ancient helminth eggs and completed the microscopic approach.
Paleoparasitological analysis was carried on 4 Merovingian skeletons, dated from the late-5th to the late-9th centuries, and recovered in the church of Saint-Martin-au-Val in Chartres (Center region, ...France). The corpses were buried in stone sarcophagi, which were still sealed at the time of excavation. Parasite marker extraction was conducted on sediment samples taken from the abdominal and pelvic regions, but also on samples taken from under the head and the feet as control samples. Microscopic observation revealed the presence of 3 gastrointestinal parasites, namely the roundworm (Ascaris lumbricoides), the whipworm (Trichuris trichiura) and the fish tapeworm (genus Diphyllobothrium). This analysis contributes to a better knowledge of the health status and the lifestyle of ancient medieval populations during the Merovingian period, for which very few paleoparasitological data were available, up until now. It demonstrates the presence of the fish tapeworm for the first time during this period.
El hallazgo de parásitos procedentes de contextos arqueológicos nos permite conocer las condiciones socio-económicas y los hábitos alimentarios de las poblaciones pasadas, aportando una visión ...novedosa en el estudio de dichas sociedades. Pese a su probado interés en la contribución al conocimiento de los estudios arqueológicos, antropológicos y biológicos, apenas se han llevado a cabo investigaciones paleoparasitológicas en España. Este trabajo presenta los resultados de los análisis paleoparasitológicos desarrollados sobre restos esqueletizados de ocho individuos procedentes de la necrópolis romana de Dianium (Dénia, Alicante, España), fechada entre los siglos III a V d.C. Este análisis se ha realizado mediante visualización por microscopía óptica de campo claro. Los resultados han evidenciado la presencia de Ascaris lumbricoides en uno de los individuos. Estos resultados se han integrado con los hallazgos paleopatológicos y antropológicos. La presencia de este parásito se vincula a la falta de higiene, derivada de contaminación ambiental y alimentaria.
La langue norne, dans son état attesté dans la Ballade d'Hildina (transmise en 1774), présente dans les expressions possessives différentes configurations, selon que le possessif soit antéposé ou ...postposé, et qu'il soit accompagné d'une marque de définitude ou non. Une analyse exhaustive des données fait apparaître que l'antéposition du possessif est marquée – on peut alors parler d'antéposition emphatique ou contrastive – trait partagé avec d'autres langues scandinaves anciennes ou modernes. La question de la définitude singularise néanmoins les données nornes: il apparaît en effet que ce qui s'apparente à un article défini ait une distribution sémantique, en servant régulièrement d'anaphorique, et non syntaxique, contrairement au norvégien par exemple. Ce trait va dans le sens d'un degré relativement faible de grammaticalisation de l'article défini. En supposant toutefois que la langue norne ait, comme les autres langues scandinaves, développé une catégorie syntaxique de determiner, les possessifs occuperaient seuls cette position syntaxique, indépendamment de leur place dans le groupe nominal: les possessifs de la langue norne entreraient ainsi dans une structure DG malgré la présence d'un article défini, qui peut alors être considéré ou bien comme une marque d'accord dans le cadre d'une double définitude, ou comme un élément sémantique sans rôle dans la définitude.
La paléoparasitologie Bailly, Matthieu Le; Maicher, Céline; Dufour, Benjamin
Nouvelles de l'archéologie,
12/2017, Volume:
148
Journal Article
Peer reviewed
Open access
Introduction La paléoparasitologie étudie les parasites anciens dont les marqueurs préservés sont retrouvés dans les sites archéologiques et paléontologiques. Située à l’interface entre l’archéologie ...et la parasitologie, cette discipline fait aussi appel à des notions issues de l’anthropologie, de l’écologie et des sciences de la santé. De par cette pluridisciplinarité, la paléoparasitologie intéresse naturellement les sciences de l’homme mais elle permet aussi d’élaborer des scenarii sur l’h...
In order to improve paleoparasitological analyses, we tested different acid (hydrochloric and hydrofluoric acids) and base (sodium hydroxide) combinations for parasite egg extraction in ...archaeological sediments. We used a method of egg counting to compare these results to those obtained with the standard paleo-parasitological RHM extraction protocol (rehydration-homogenization-micro-sieving). Tests show that the use of hydrochloric acid results in a concentration of some taxa like Ascaris sp. or Trichuris sp. and an appreciable decrease in vegetal and mineral remains. However, tests also show that acid use systematically decreases parasite species identified, as compared to the standard RHM protocol. Base use yielded even more negative results with systematically lower biodiversity than with the standard protocol, probably due to chemical processes on chitin contained in the eggshell. These results suggest acids and sodium hydroxide should be used as little as possible during extraction due to the damages they cause to the eggs of some parasite species. The counting method was an efficient technique with which to demonstrate our results and could be used in future paleoparasitology studies.
•Theta-band activity is modulated by expected visual feedback during reach planning.•Alpha-band activity is modulated by the direction of expected visual feedback.•Expected visual feedback influences ...planning in spite of similar hand kinematics.
Activity in the primary motor cortex (M1) during reach planning is known to be correlated with the upcoming kinetics and kinematics of the hand. Yet recent work using visual-motor dissociation tasks suggests that M1 activity is also correlated with the visual consequences of an action, independent of the actual hand displacement. The goal of the present work was to investigate whether oscillatory activity over sensorimotor regions is modulated by the expectancy of visual reafferent feedback during reach planning. While recording electroencephalography (EEG), participants executed hand-reaching movements in a single direction (i.e., straight-ahead of midline) throughout the entire experiment. Visual feedback of the hand was provided with a cursor and was manipulated. Specifically, before each trial, participants were precued as to the nature of the upcoming visual feedback, which could be spatially congruent with the hand, rotated leftward or rightward by 20° or not provided at all. Results revealed that planning-related EEG activity at contralateral central electrodes was strongly modulated in the theta-band (3–7 Hz) depending on whether visual feedback would be available or not. In contrast, contralateral beta-band (15–30 Hz) activity did not differ across conditions. These results demonstrate that low-frequency oscillatory dynamics during reach planning depend upon the upcoming availability of visual feedback. This may relate to predicting the visual consequences of the movement or to setting different feedback gains necessary for visually guided vs. non-visually guided movements.
Understanding parasite history and the evolution of host/parasite relationships is one of the most important aspects of paleoparasitology. Within the framework of this research topic, this paper ...focuses on the human pathogenic amoeba, Entamoeba histolytica. The compilation of all the available archaeological data concerning this parasite leads to a first glimpse of the history of this parasite of current medical importance. Paleoparasitological investigation into this parasite uses immunological techniques and shows that the modern strain of E. histolytica has been present in Western Europe since at least the Neolithic period (3700yearsBCE), and could have originated in the Old World. The appearance of the modern amoeba strain in the pre-Columbian Americas and the Middle East around the 12th century CE gives rise to hypotheses as to how human migrations (Atlantic or Pacific routes) contributed to the diffusion of this pathogen, resulting in its current distribution. This compilation proves that parasites are valuable proxies for studying past human and animal migrations, and should be given more consideration in the future.
•This article reviews past occurrences of the human pathogenic amoeba.•The parasite has been present in Western Europe since the Neolithic period.•The amoeba is recovered prior to the 15th c. CE colonization of the Americas.•Human migrations contribute to diffusing the parasites during the Holocene.
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