Évaluation géostatistique de la stabilité d’une pente : Site de l’Université de Constantine (Nord-Est Algérien)

L¡¦analyse de la stabilite du site etudie (Universite Mentouri ; region de Constantine) montre qu¡¦il est instable ; le coefficient de securite Fs minimum est egal a 0,3685 qui correspond au cercle de glissement le plus profond (x,y) = (629,6 ; 600). A cet effet, le choix de la surface de rupture reste toujours probable. Ce choix qui obeie a un certain nombre de tests peut donner des resultats de calcul de Fs avec une marge d¡¦erreur relative. Des methodes geostatistiques ont ete utilisees pour quantifier la stabilisation de ce talus, et chercher l¡¦erreur d¡¦estimation. Le coefficient de securite Fs, est pris comme variable regionalisee ; le variogramme experimental omnidirectionnel a ete modelise par un schema spherique avec un effet de pipite C0 =0,0264, un palier C= 0,056, et une portee a = 6,57m. Le krigeage ordinaire de Fs, montre que les isovaleurs kriogees, varient de 0,65 a 1,4. La variance moyenne de krigeage est de 0,0529 ; ce qui donne une erreur relative de 42,18% au maximum 95%   correspondant au standard gaussien 2ƒãE. La cartographie des variances de krigeage montre qu¡¦il y a des zones sous ¡V reconnues ; l¡¦erreur est faible pour un coefficient de securite inferieur a 1 (zone instable) ; par ailleurs elle est relativement forte pour Fs superieur a 1 (zone classee stable par le calcul classique de Bishop). Cependant, si la precision dans l¡¦estimation de la stabilite de talus devait etre grande, alors d¡¦autres calculs de ce coefficient sont necessaires. Cette etude de quantification et verification de stabilite de talus reste valable pour l¡¦analyse regionalisee de la stabilite de n¡¦importe quel site qui souffre d¡¦un probleme de glissement.Mots- cles : geotechnique, geostatistique, variogramme experimental, krigeage ordinaire, cartographie

Towards the security of McEliece's cryptosystem based on Hermitian subfield subcodes

The purpose of this paper is to provide a comprehensive security analysis for the parameter selection process, which involves the computational cost of the information set decoding algorithm using the parameters of subfield subcodes of 1-point Hermitian codes. The purpose of this paper is to provide a comprehensive security analysis for the parameter selection process, which involves the computational cost of the information set decoding (ISD) algorithm using Hermitian subfield subcode parameters

Mixing of Au in Si induced by secondary and high-order recoil implantation

The mixing of Au in Si induced by secondary and high-order recoil implantation was investigated using 350 keV Ar + and 350 keV Kr + ions to fluences from 1?×?10 16 to 3?×?10 16 ions/cm 2 at room temperature. The thickness of the Au layer evaporated on Si substrate was ~2400 .The ranges of the Ar and Kr ions were chosen to be lower than the thickness of the Au layer in order to avoid the ballistic mixing produced by the primary knock-on atoms. Rutherford backscattering spectrometry (RBS) experiments were carried out to study the effects induced by Ar and Kr irradiation at the interface of Au-Si system. We observed that in the case of the irradiation with Ar + ions, a broadening of the Au-Si interface occurred only at the fluence of 3?×?10 16 Ar + /cm 2 and it is attributed to the surface roughening induced by ion bombardment. In contrast, the RBS analysis of a sample irradiated with 2?×?10 16 Kr + /cm 2 clearly showed, in addition to the broadening effect, the formation of a mixed zone of Au and Si atoms at the interface. The mixing of Au in Si atoms can be explained by the secondary and high-order recoil implantation followed by subsequent collision cascade

Rhanteriol, a New Rhanterium suaveolens Desf. Lignan with Pharmacological Potential as an Inhibitor of Enzymes Involved in Neurodegeneration and Type 2 Diabetes

Several specialized plant metabolites are reported to be enzyme inhibitors. In this investigation, the phytochemical composition and the biological activity of Rhanterium suaveolens Desf. were studied. One new lignan (rhanteriol 1) and seven known secondary metabolites were isolated from the aerial parts of R. suaveolens by using different chromatographic procedures. The biological properties of the R. suaveolens extracts and the new compound were evaluated by measuring their ability to inhibit the cholinesterase and carbohydrate-hydrolyzing enzymes, using cell-free in vitro methods. The new lignan, rhanteriol, was shown to inhibit alpha-amylase and alpha-glucosidase (IC50 = 46.42 +/- 3.25 mu M and 26.76 +/- 3.29 mu M, respectively), as well as butyrylcholinesterase (IC50 = 10.41 +/- 0.03 mu M), with an effect comparable to that of the respective standards, acarbose and galantamine. Furthermore, docking studies were performed suggesting the interaction mode of rhanteriol with the active sites of the investigated enzymes. The obtained data demonstrated that the aerial part of R. suaveolens could represent a source of active molecules, such as rhanteriol, usable in the development of treatments for preventing or treating type 2 diabetes mellitus and neurodegeneration

An obstetric sphincter injury risk identification system (OSIRIS): is this a clinically useful tool?

INTRODUCTION AND HYPOTHESIS: To establish the contribution of maternal, fetal and intrapartum factors to the risk of incidence of obstetric anal sphincter injuries (OASIS) and assess the feasibility of an OASIS risk prediction model based on variables available to clinicians prior to birth. METHODS: This was a population-based, retrospective cohort study using single-site data from the birth database of Aarhus University Hospital, Denmark. The participants were all women who had a singleton vaginal birth during the period 1989 to 2006. Univariate and multivariate logistic regression analyses were performed using multiple imputations for missing data and internally validated using bootstrap methods. The main outcome measures were the contributions of maternal, fetal and intrapartum events to the incidence of OASIS. RESULTS: A total of 71,469 women met the inclusion criteria, of whom 1,754 (2.45 %) sustained OASIS. In the multivariate analysis of variables known prior to birth, maternal age 20 – 30 years (OR 1.65, 95 % CI 1.44 – 1.89) and ≥30 years (OR 1.60, 95 % CI 1.39 – 1.85), occipitoposterior fetal position (OR 1.34, 95 % CI 1.06 – 1.70), induction/augmentation of labour (OR 1.46, 95 % CI 1.32 – 1.62), and suspected macrosomia (OR 2.20, 95 % CI 1.97 – 2.45) were independent significant predictors of OASIS, with increasing parity conferring a significant protective effect. The ‘prebirth variable’ model showed a 95 % sensitivity and a 24 % specificity in predicting OASIS with 1 % probability, and a 3 % sensitivity and a 99 % specificity in predicting OASIS with a 10 % probability. CONCLUSIONS: Our model identified several significant OASIS risk factors that are known prior to actual birth. The prognostic model shows potential for ruling out OASIS (high sensitivity with a low risk cut-off value), but is not useful for ruling in the event. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00192-016-3125-2) contains supplementary material, which is available to authorized users

Creation of multiple nanodots by single ions

In the challenging search for tools that are able to modify surfaces on the nanometer scale, heavy ions with energies of several 10 MeV are becoming more and more attractive. In contrast to slow ions where nuclear stopping is important and the energy is dissipated into a large volume in the crystal, in the high energy regime the stopping is due to electronic excitations only. Because of the extremely local (< 1 nm) energy deposition with densities of up to 10E19 W/cm^2, nanoscaled hillocks can be created under normal incidence. Usually, each nanodot is due to the impact of a single ion and the dots are randomly distributed. We demonstrate that multiple periodically spaced dots separated by a few 10 nanometers can be created by a single ion if the sample is irradiated under grazing angles of incidence. By varying this angle the number of dots can be controlled.Comment: 12 pages, 6 figure

Formation of silicon nanodots via ion beam sputtering of ultrathin gold thin film coatings on Si

Ion beam sputtering of ultrathin film Au coatings used as a physical catalyst for self-organization of Si nanostructures has been achieved by tuning the incident particle energy. This approach holds promise as a scalable nanomanufacturing parallel processing alternative to candidate nanolithography techniques. Structures of 11- to 14-nm Si nanodots are formed with normal incidence low-energy Ar ions of 200 eV and fluences above 2 × 1017 cm-2. In situ surface characterization during ion irradiation elucidates early stage ion mixing migration mechanism for nanodot self-organization. In particular, the evolution from gold film islands to the formation of ion-induced metastable gold silicide followed by pure Si nanodots formed with no need for impurity seeding

Genome wide analysis of gene expression changes in skin from patients with type 2 diabetes

Non-healing chronic ulcers are a serious complication of diabetes and are a major healthcare problem. While a host of treatments have been explored to heal or prevent these ulcers from forming, these treatments have not been found to be consistently effective in clinical trials. An understanding of the changes in gene expression in the skin of diabetic patients may provide insight into the processes and mechanisms that precede the formation of non-healing ulcers. In this study, we investigated genome wide changes in gene expression in skin between patients with type 2 diabetes and non-diabetic patients using next generation sequencing. We compared the gene expression in skin samples taken from 27 patients (13 with type 2 diabetes and 14 non-diabetic). This information may be useful in identifying the causal factors and potential therapeutic targets for the prevention and treatment of diabetic related diseases

Characterization of MHz pulse repetition rate femtosecond laser-irradiated gold-coated silicon surfaces

In this study, MHz pulse repetition rate femtosecond laser-irradiated gold-coated silicon surfaces under ambient condition were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), and X-ray photoelectron spectroscopy (XPS). The radiation fluence used was 0.5 J/cm2 at a pulse repetition rate of 25 MHz with 1 ms interaction time. SEM analysis of the irradiated surfaces showed self-assembled intermingled weblike nanofibrous structure in and around the laser-irradiated spots. Further TEM investigation on this nanostructure revealed that the nanofibrous structure is formed due to aggregation of Au-Si/Si nanoparticles. The XRD peaks at 32.2°, 39.7°, and 62.5° were identified as (200), (211), and (321) reflections, respectively, corresponding to gold silicide. In addition, the observed chemical shift of Au 4f and Si 2p lines in XPS spectrum of the irradiated surface illustrated the presence of gold silicide at the irradiated surface. The generation of Si/Au-Si alloy fibrous nanoparticles aggregate is explained by the nucleation and subsequent condensation of vapor in the plasma plume during irradiation and expulsion of molten material due to high plasma pressure