Contribution of Surfactin and SwrA to Flagellin Expression, Swimming, and Surface Motility in Bacillus subtilis.

Multicellular communities produced by Bacillus subtilis can adopt sliding or swarming to translocate over surfaces. While sliding is a flagellum-independent motility produced by the expansive forces in a growing colony, swarming requires flagellar functionality and is characterized by the appearance of hyperflagellated swarm cells that associate in bundles or rafts during movement. Previous work has shown that swarming by undomesticated B. subtilis strains requires swrA, a gene that upregulates the expression of flagellar genes and increases swimming motility, and surfactin, a lipopeptide biosurfactant that also facilitates sliding. Through an analysis of swrA(+) and swrA mutant laboratory strains with or without a mutation in sfp (a gene involved in surfactin production), we show that both swrA and surfactin upregulate the transcription of the flagellin gene and increase bacterial swimming. Surfactin also allows the nonswarming swrA mutant strain to efficiently colonize moist surfaces by sliding. Finally, we reconfirm the essential role of swrA in swarming and show that surfactin, which increases surface wettability, allows swrA(+) strains to produce swarm cells on media at low humidity

Acute complications of preeclampsia: prognosis and management at Pikine National Hospital in Dakar (Senegal)

ABSTRACTBackground: The objective of this study was to evaluate the prevalence of acute complications of preeclampsia in order to describe the epidemiological profile of the disease, to assess its prognosis and management.Methods: This was a retrospective study of patients admitted to the Pikine National Hospital from 1 January 2010 to 31 December 2013 (48 months) with severe complicated pre-eclampsia. Included in this study were patients admitted or diagnosed with severe complicated pre-eclampsia and having given birth in the structure or not.Results: The incidence of severe preeclampsia in childbirth varied from 9.7% to 11.5% during the four years of our study. Patients were largely paucigest (55.7% of cases) and paucipares (58.5% of cases). The mean age was 28.14 years with extremes of 14 and 47 years. More than half of the patients (57.7%) were between 21 and 34 years of age. They were mostly married (90.7%). Three-quarters of the patients (76.8%) had proteinuria with ≥ 3 cross-bands. Thrombocytopenia was found in 9.7% of patients, hepatic cytolysis in 12.1%, and elevation of serum creatinine in 13.8%. The level of transaminases was found to be greater than 2 in the normal range in 12.1%. Complicated forms were the most represented in our study. These were acute complications, with 715 cases, or 57.3% of the patients. They were either isolated (52.8%) or associated (4.5%). These included eclampsia (24.9%), followed by retroplacental hematoma (24.6%), fetal death in utero (23.7%), HELLP syndrome (3.4%). , Acute edema of the lungs (1.5%), and acute renal failure (1.4%). The lethality was 2.4%. The causes of maternal death were dominated by eclampsia (14 cases), DIC (3 cases) and OAP (2 cases). We counted 77.7% of live births and a stillbirth of 254.5 ‰.Conclusions: Pre-eclampsia is a serious complication of pregnancy. Its frequency is still high in sub-Saharan Africa. In the presence of signs of severity, maternal (vital and functional) and neonatal prognosis are inevitably involved. If management is based on fetal extraction, resuscitation measures are a guarantee of maternal survival

Etudes comparatives sur les bovins N'Dama de haute Casamance pour évaluer leur trypanotolérance en fonction de la couleur de leur robe

Les techniques les plus modernes pour la diagnose des trypanosomoses: (technique de Woo, examen sur lames, immunofluorescence, test micro ELISA, test immunospécifique par comptage enzymatique) ont été utilisées sur du bétail N'Dama de Haute-Casamance, au Sénégal, pour vérifier si la qualité de leur trypanotolérance est en relation avec la couleur de leur robe, compte tenu de la réputation qu'ont les N'Dama de couleur fauve d'être les plus résistants. Des observations faites, qui ont porté sur 210 sujets pour les examens hématologiques et parasitaires, et sur 260 pour les études de sérologie, il résulte que les N'Dama de couleur fauve ne sont ni plus ni moins trypanotolérants que ceux à robe blanche, noire ou pie, ces derniers ayant souvent, par ailleurs, une remarquable conformation d'animaux de trait ou de boucherie. Il n'y a donc apparemment aucune raison qui justifie le choix de la seule couleur fauve comme critère de race plus résistante aux trypanosomoses. Les auteurs préconisent donc l'abandon de ce critère racial, avec le bénéfice a en attendre au plan de la sélection et de la diffusion d'animaux de cette rac

Ternary Syndrome Decoding with Large Weight

The Syndrome Decoding problem is at the core of many code-based cryptosystems. In this paper, we study ternary Syndrome Decoding in large weight. This problem has been introduced in the Wave signature scheme but has never been thoroughly studied. We perform an algorithmic study of this problem which results in an update of the Wave parameters. On a more fundamental level, we show that ternary Syndrome Decoding with large weight is a really harder problem than the binary Syndrome Decoding problem, which could have several applications for the design of code-based cryptosystems

Sustainable development in the mining industry: Towards the development of tools for evaluating socioeconomic impact in the Canadian context

In spite of its economic outputs, the Canadian mining sector has suffered from several setbacks that have compromised its reputation. This has led many of its stakeholders to adopt a shift towards a new paradigm focused on sustainable development. In this review of the literature, we identify the impact that mining activities have had on various social, economic and environmental issues in Canadian society. We also survey the criteria and indicators included in various models that may be used to evaluate the adequacy of the transition of mines towards sustainable development. Finally, the strengths and weaknesses of eight tools that have been applied to the socioeconomic impact of mines are analysed. A clear vision of prospects for promoting sustainable development in Canadian mining emerges from this survey. Our analysis reveals important factors not given adequate consideration in the models used currently to evaluate and suggests opportunities to improve these evaluation tools through identification of more relevant criteria and indicators. The research undertaken should incite stakeholders to develop social and economic impact evaluation tools that are better adapted to the Canadian context

Multi-criteria evaluation of the socioeconomic impact of mining in Canada from a sustainable development perspective: A theoretical model

The socioeconomic impact of mining in Canada has positive and negative aspects. Effective evaluation of its impact suffers from the inadequacy of the criteria and indicators chosen to measure its sustainability and the limitations of the current means used to minimize the subjectivity of expert judgments. Constraints associated with legislation and standards governing mining activities must also be considered. In this study, a theoretical model is proposed for evaluating the socioeconomic impact of mining in Canada. This model combines the multi-criteria analysis methods known as the analytic hierarchy process and fuzzy integrated judgment. Based on a simulation, the model is able to take into account the subjectivity of expert judgments. In addition to reducing this subjectivity and allowing measurement of sensitivity, the model provided an overview of the progress achieved by a mine during its transition towards sustainable development

Interaction of (3-Aminopropyl)triethoxysilane with Pulsed Ar-O 2 Afterglow: Application to Nanoparticles Synthesis

International audienceThe interaction of (3-Aminopropyl)triethoxysilane (APTES) with pulsed late Ar-O 2 afterglow is characterized by the synthesis of OH, CO and CO 2 in the gas phase as main by-products. Other minor species like CH, CN and C 2 H are also produced. We suggest that OH radicals are produced in a first step by dehydrogenation of APTES after interaction with oxygen atoms. In a second step, the molecule is oxidized by any O 2 state, to form peroxides that transform into by-products, break thus the precursor CC bonds. If oxidation is limited, i.e. a low duty cycle, fragmentation of the precursor is limited and produced nanoparticles keep the backbone structure of the precursor, but contain amide groups produced from the amine groups initially available in APTES. At high duty cycle, silicon-containing fragments contain some carbon and react together and produce nanoparticles with a non-silica-like structure

The E00-110 experiment in Jefferson Lab's Hall A: Deeply Virtual Compton Scattering off the Proton at 6 GeV

We present final results on the photon electroproduction ($\vec{e}p\rightarrow ep\gamma$) cross section in the deeply virtual Compton scattering (DVCS) regime and the valence quark region from Jefferson Lab experiment E00-110. Results from an analysis of a subset of these data were published before, but the analysis has been improved which is described here at length, together with details on the experimental setup. Furthermore, additional data have been analyzed resulting in photon electroproduction cross sections at new kinematic settings, for a total of 588 experimental bins. Results of the $Q^2$- and $x_B$-dependences of both the helicity-dependent and helicity-independent cross sections are discussed. The $Q^2$-dependence illustrates the dominance of the twist-2 handbag amplitude in the kinematics of the experiment, as previously noted. Thanks to the excellent accuracy of this high luminosity experiment, it becomes clear that the unpolarized cross section shows a significant deviation from the Bethe-Heitler process in our kinematics, compatible with a large contribution from the leading twist-2 DVCS$^2$ term to the photon electroproduction cross section. The necessity to include higher-twist corrections in order to fully reproduce the shape of the data is also discussed. The DVCS cross sections in this paper represent the final set of experimental results from E00-110, superseding the previous publication.Comment: 48 pages, 32 figure