Bursting of rigid bubbles

We propose here a fluid dynamics video relating the bursting of soap rigid films.Comment: 4 pages and 2 videos included for the Gallery of Fluid Motion 201

Holes and cracks in rigid foam films

The classical problem of foam film rupture dynamics has been investigated when surfaces exhibit very high rigidity due to the presence of specific surfactants. Two new features are reported. First a strong deviation to the well-known Taylor-Culick law is observed. Then, crack-like patterns can be visualized in the film; these patterns are shown to appear at a well defined deformation. The key role of surface active material on these features is quantitatively investigated, pointing the importance of surface elasticity to describe these fast dynamical processes, and thus providing an alternative tool to characterize surface elasticity in conditions extremely far from equilibrium. The origin of the cracks and their consequences on film rupturing dynamics are also discussed

Sélestat – Allée Georges-Charpak

Localisé dans la zone industrielle sud-ouest de Sélestat, à proximité de la RD 424 reliant Châtenois à Sélestat, le site de l’allée Georges-Charpak d’une superficie de 13 893 m2 a fait l’objet d’un diagnostic archéologique en vue d’aménager un complexe sportif ainsi qu’un parking. 26 sondages ont été réalisés jusqu’au toit des graviers correspondant au sommet du cône de déjection quaternaire du Giessen. Aucun vestige anthropique d’origine ancienne n’a été découvert, à l’exception de six fosse..

Apc mutation induces resistance of colonic cells to lipoperoxide-triggered apoptosis induced by faecal water from haem-fed rats

Recent epidemiological studies suggest that high meat intake is associated with promotion of colon cancer linked to haem-iron intake. We previously reported that dietary haem, in the form of either haemoglobin or meat, promotes precancerous lesions in the colon of rats given a low-calcium diet. The mechanism of promotion by haem is not known, but is associated with increased lipid peroxidation in faecal water and strong cytotoxic activity of faecal water on a cancerous mouse colonic epithelial cell line. To better understand the involvement of faecal water components of haem-fed rats in colon cancer promotion, we explored the effect of faecal water on normal (Apc +/+) or premalignant cells (Apc Min/+). Further, we tested if this effect was correlated to lipoperoxidation and 4-hydroxynonenal (HNE). We show here for the first time that heterozygote Apc mutation represents a strong selective advantage, via resistance to apoptosis induction (caspase 3 pathway), for colonic cells exposed to a haem-iron induced lipoperoxidation. The fact that HNE treatment of the cells provoked the same effects as the faecal water of rats fed the haem-rich diet suggests that this compound triggers apoptosis in those cells. We propose that this mechanism could be involved in the promotion of colon carcinogenesis by haem in vivo

Brain, language, and handedness: a family affair

The left planum temporale is a marker of left hemisphere language specialization. We investigated the effect of individual handedness and familial sinistrality on left planum temporale surface area and found the size is reduced in proportion with the number of left-handed immediate family members and is lowest when one's mother is left-handed. This reduction is independent of an individual's handedness or sex and has no counterpart in the right hemisphere

Extraction of a tricarboxylic acid from a sugar-cane by-product – Study and modeling of the anion-exchange step

Extraction of a tricarboxylic acid from a sugar-cane by-product – Study and modeling of the anion-exchange step . 16. Congrès de la Société Française de Génie des Procédés "Le Génie des Procédés au Service de l'Homme" (SFGP 2017

Films de savons rigides : dynamique de rupture

L’éclatement d’un film de savon, dont les premières études remontent au début du XXe siècle, est généralement décrit par la compétition entre l’inertie du liquide mis en mouvement et la tension de surface d’équilibre, responsable de l’ouverture du trou [1, 2, 3]. D’un autre côté, dans les films de savon ou les mousses, qui sont des assemblées de films, plusieurs phénomènes dynamiques comme le drainage [4] ou la rhéologie [5] dépendent de façon cruciale de la nature des molécules tensioactives, qui peuvent rigidifier les interfaces liquide-gaz. Nous étudions ici l’éclatement d’un film de liquide contenant un mélange de tensioactifs réputé pour sa grande élasticité inter faciale [6]. Dans ce cas, nous montrons que les tensioactifs sont responsables d’un ralentissement de la dynamique d’ouverture par rapport à la loi classique de Taylor-Culick. Cette dynamique est pilotée par la compétition entre l’inertie et l’élasticité de surface que nous contrôlons. De façon similaire à ce que l’on observe pour une membrane élastique solide, pour de grandes compressions, la rigidité des interfaces conduit à la formation de motifs localisés, comparables à des plis ou des fractures. Nous montrons que l’apparition de ces motifs s’accompagne d’une modification de la dynamique d’ouverture

Evaluation of Two New Commercial Tests for the Diagnosis of Acute Dengue Virus Infection Using NS1 Antigen Detection in Human Serum

Dengue is a viral disease transmitted by mosquitoes that is endemic in more than 100 countries in tropical areas, threatening over 2.5 billion people. It causes a wide range of symptoms and has severe forms. In reference laboratories, dengue disease is confirmed by virus isolation or genome detection during the acute phase, and by serological methods during the early convalescent phase. The viral NS1 protein circulates in the sera of infected patients throughout the clinical phase of the disease. Novel diagnostic tests based on NS1 detection have been recently developed and marketed. We compared the performance of two tests for detecting dengue NS1 protein during the clinical phase of dengue infection (an immunochromatographic test (ICT) from Bio-Rad allowing rapid detection of the NS1 antigen and a two-step sandwich-format ELISA from Panbio) with the one-step sandwich-format microplate ELISA (Bio-Rad). The ICT test performed better than the ELISA test from Panbio. This study confirms that diagnostic tests based on NS1 could be used in routine clinical practice in poorly equipped laboratories and that dengue diagnosis could therefore be confirmed without the need for testing in reference laboratories. This represents a crucial step towards the control of dengue disease in the human population