Pitch-Axis Identification for a Guided Projectile Using a Wind-Tunnel-Based Experimental Setup

International audienceThis paper details the identification of a pitchaxis model for an 80-mm fin-stabilized canard-guided projectilethrough a hardware-in-the-loop experimental setup. This setup is based on an autonomous functional projectileprototype installed in a subsonic wind tunnel by the means of a three-degree-of-freedom gimbal mount. A nonlinear dynamical model is first derived from flight mechanics principles;then, a linearized model is obtained through Taylorseries expansion. The a priori and a posteriori identifiabilityof the proposed linear model are assessed, and the associatedexperimental input signals are accordingly designed.The model parameters are then estimated using a numericaloptimization procedure, and the associated uncertainty isobtained through a boostrapping method. The results andtheir implication on the projectile flight control design arefinally discussed

Resonant absorption of a chemically sensitive layer based on waveguide gratings

A colorimetric sensor providing a direct visual indication of chemical contamination was developed. The sensor is a combination of a chemically sensitive dye layer and a resonant waveguide grating. Enhancement of the light absorption by the photonic structure can be clearly seen. The detection is based on the color change of the reflected light after exposure to a gas or a liquid. Low-cost fabrication and compatibility with environments where electricity cannot be used make this device very attractive for applications in hospitals, industries, with explosives, and in traffic

Sex difference in pathology of the ageing gut mediates the greater response of female lifespan to dietary restriction

Women live on average longer than men, but have greater levels of late-life morbidity. We have uncovered a substantial sex difference in the pathology of the ageing gut in Drosophila. The intestinal epithelium of the ageing female undergoes major deterioration, driven by intestinal stem cell (ISC) division, while lower ISC activity in males associates with delay or absence of pathology, and better barrier function, even at old ages. Males succumb to intestinal challenges to which females are resistant, associated with fewer proliferating ISCs, suggesting a trade-off between highly active repair mechanisms and late-life pathology in females. Dietary restriction reduces gut pathology in ageing females, and extends female lifespan more than male. By genetic sex reversal of a specific gut region, we induced female-like ageing pathologies in males, associated with decreased lifespan, but also with a greater increase in longevity in response to dietary restriction

Elevated serum matrix metalloproteinase 9 (MMP-9) concentration predicts the presence of colorectal neoplasia in symptomatic patients

Early detection of polyps or colorectal carcinoma can reduce colorectal carcinoma-associated deaths. Previous studies have demonstrated raised serum levels of matrix metalloproteinase 9 (sMMP-9) in a range of cancers. The aim of this study was to investigate the role of sMMP-9 levels in identifying colorectal neoplasia. Consenting patients donated a blood sample and were assessed by proforma-led history and physical examination. Samples were analysed for sMMP-9 concentration (enzyme-linked immuno-sorbant assay) and compared to final diagnoses. Logistic regression modelling determined independent factors associated with neoplasia. A total of 365 patients were recruited of whom 300 were analysed, including 46 normal controls. A total of 27 significant adenomas and 63 malignancies were identified. The median sMMP-9 concentration was 443ng ml−1 (IQR: 219–782; mean: 546). Patients with neoplasia had significantly elevated sMMP-9 levels (P<0.001). Logistic regression modelling identified elevated log(sMMP-9) as the most significant predictor of neoplasia (χ2=38.33, P<0.001). Other significant factors were age, sex, smoking history, abdominal pain and weight loss. The model accurately predicted neoplasia in 77.3% of cases. Sensitivity and specificity were 77.9 and 77.1%. sMMP-9 estimation can accurately stratify patient to low- or high-risk cohorts. Serum sampling is a potential means of avoiding unnecessary colonoscopy and reducing patient anxiety, iatrogenic morbidity and mortality, and cost

Primary Analysis of Phase 2 Results for Cemiplimab in Patients (pts) with Locally Advanced Basal Cell Carcinoma (laBCC) who Progress on or are Intolerant to Hedgehog Inhibitors (HHIs)

Abstract not available

Tourisme et chamanisme : Entre folklorisation et revitalisation culturelle ?

Depuis une dizaine d’années, le tourisme chamanique a fait son apparition sur le marché touristique, notamment au Pérou, au Mexique et aux États-Unis. Bien que ce type de pratique demeure marginal, il semble intéressant à étudier d’un point de vue socio-anthropologique afin de comprendre les relations d’altérité qu’entretiennent les visiteurs auprès des sociétés visitées, et de mesurer les impacts d’une culture globalisée auprès d’une société amérindienne traditionnelle. Mes études de terrain menées au Mexique dans la réserve naturelle sacrée de Wirikuta située dans l’État de San Luis Potosi m’ont permis d’arriver à quelques conclusions. D’abord, contrairement aux approches classiques dénonçant l’inéluctable folklorisation et uniformisation culturelle de la société réceptrice, le processus d’idéalisation et de commercialisation d’une culture amérindienne par le biais du tourisme peut donner lieu à une reconnaissance culturelle auprès d’un plus large public. De plus, il peut entraîner ainsi une revitalisation culturelle d’un point de vue local et une diversification culturelle d’un point de vue global. Autrement dit, le tourisme chamanique ou mystico-spirituel déstabilise la tradition tout en la renforçant, et s’approprie un patrimoine matériel et immatériel tout en participant à la création de nouveaux mouvements religieux et sociaux, tels que le néochamanisme

Del turismo al neochamanismo: ejemplo de la reserva natural sagrada de Wirikuta en México

Over the last decade, a new niche of tourism activity has been developing on the fringes of the world tourism market: mystical-spiritual tourism. Classed as ethnic tourism and the search for spiritual experience, more and more international travellers, fascinated with the native peoples, are submerging themselves in the “so called” cultural traditions by way of initiations or shamanic rituals. In Latin America, the most emblematic locations of the pre-Hispanic cultures have become the object of numerous tourism businesses. Whether organized by professional travel agencies, or considered as “native” by the authorities, these activities investin new spaces bereft of any form of appropriate infrastructure. Based on a study carried out at the sacred Wirikuta natural reserve in Mexico, a place of pilgrimage for the Wixaritari indians, theidea is to provide a better understanding of the realities and risks related to this type of tourismactivity. If this type of tourism tends to overestimate the figure of the Amerindian, elevating them to the rank of authentic indian, and thus seen as the redeemer of the white man, this study also —paradoxically— demonstates that this phenomenon of rediscovery and reappropriationof native shamanism represents ?for the tourist? the possibility of transcultural communication through which his/her “identity” undergoes some form of transformation.Desde hace unos diez años, un nuevo sector de actividades turísticas tiende a desarrollarse al margen del mercado mundial: el turismo místico-espiritual. Entre el etnoturismo y la búsqueda de experiencias espirituales, cada vez más viajeros internacionales fascinados con los pueblos autóctonos tienden a sumergirse en culturas llamadas tradicionales a través de una iniciación o inmersión chamánica. En América Latina, los lugares más emblemáticos de las culturas prehispánicas se han vuelto objeto de numerosas especulaciones turísticas. Bien sean enmarcadas por agencias profesionales o que sean consideradas como “salvajes” por las autoridades, estas actividades invierten en nuevos espacios carentes de todo tipo de infraestructura adaptada. Apoyándome en un estudio llevado a cabo en la reserva natural sagrada de Wirikuta, en México, espacio de peregrinación de los indios wixaritari, se tratará de entender mejor a través de este ejemplo las realidades y los riesgos de tales prácticas turísticas. Si este tipo de turismo tiende a sobreestimar la figura del amerindio —y a elevarlo al rango de indio auténtico, como redentor del hombre blanco—, este estudio contribuye también a demostrar, paradójicamente, que el fenómeno de redescubrimiento y de reapropiación del chamanismo autóctono representa para el turista una posibilidad de establecer una comunicación transcultural durante la cual él sufre una transformación de identidad