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Seasonal deformation of mountain rock slopes can be driven by groundwater infiltration and depletion. Such processes could explain our field observation in the Aletsch Valley, Switzerland, where GNSS‐derived 3D annual displacement amplitudes reach 3.4 cm. However, the physical mechanisms behind such groundwater‐driven surface displacements are not well understood. Here, we develop a fully coupled hydromechanical model to simulate the relevant processes in a valley slope embedded with numerous fractures of variable sizes. The magnitude and orientation of transient annual slope surface displacement obtained from our model are in overall agreement with the field observations. The key geological factors controlling the type and magnitude of reversible mountain slope deformations are fracture network geometry, fracture aperture, and regional stress field. We show that the heterogeneity and anisotropy of bedrock hydromechanical responses, originating from depth‐dependent variations of fracture properties, play a critical role in groundwater recharge and valley slope deformation. During recharge events, pore pressure perturbations migrate downward from the groundwater table and toward the receiving stream and the deep subsurface. This process driven by pressure diffusion and poroelastic stressing develops in the subsurface with a great reach of up to a few kilometers, called critical hydromechanical response zone, and controls surface deformation patterns. During groundwater recession, this hydromechanical response zone expands downward and ground surface displacement vectors rotate upwards. Our results suggest that slope surface deformation can inform about subsurface permeability structures and pore pressure fluctuations, which have important implications for understanding groundwater flow in fractured bedrock slopes. Groundwater recharge in alpine valleys mainly occurs during snowmelt and/or rainstorm events. When recharge raises groundwater table in the slope, the bedrock can deform, and centimeter‐scale surface displacements can be observed. Here, we model this process in an alpine valley and investigate how bedrock fractures and regional stresses affect the surface displacement pattern. We show that slope surface deformation is controlled by a so‐called hydromechanical response zone reaching up to a few kilometers below the valley ridges. The shape and location of this zone change throughout the year. We compare our modeling results with long‐term deformation records from the lower Aletsch Valley, Switzerland, and show that they are in general agreement. The results of this work and insights obtained advance our fundamental understanding of the mechanisms of groundwater‐driven deformations in fractured rock slopes. Our research opens an avenue to use the information of surface deformation patterns to infer subsurface hydrogeological processes. Coupled hydromechanical simulations are compared to surface displacement magnitude, orientation and hysteresis observed at Aletsch, SwitzerlandGroundwater recharge‐related pressure diffusion and poroelastic stressing in subsurface rock drive slope surface displacementCentimeter‐scale slope surface displacements occur in fractured crystalline rock with permeability in the narrow range of 10−16–10−14m2 Coupled hydromechanical simulations are compared to surface displacement magnitude, orientation and hysteresis observed at Aletsch, Switzerland Groundwater recharge‐related pressure diffusion and poroelastic stressing in subsurface rock drive slope surface displacement Centimeter‐scale slope surface displacements occur in fractured crystalline rock with permeability in the narrow range of 10−16–10−14m2

Deux études de cas sur la biocontamination de tableaux par des champignons filamenteux sont présentées. La première étude concerne les analyses microbiologiques des tableaux du chemin de croix (xixème siècle) de la cathédrale de Saint Front de Périgueux. La deuxième étude présente les résultats de l’analyse microbiologique du tableau Résurrection de Lazare (XVIIème siècle) du Château de Bourdeilles. Il s’agît d’un travail pluridisciplinaire faisant intervenir les connaissances du conservateur, du restaurateur et du microbiologiste afin de choisir le traitement le plus efficace en adéquation avec les micromycètes impliqués et le support à traiter.

BIOSAF: RESULT OF THE EXPERIENCE The zootechnical efficiency of probiotics should be, during the next years, less and less disputed. But, if controversies still exist because of ignorance of their [...]

Le recours au thermalisme dans le psoriasis s’entend comme complémentaire ou comme une phase de pause entre des traitements. Cependant il souffre de l’absence d’évaluation objective en l’absence d’étude multicentrique randomisée.

Le traitement du « mal de gorge », considéré comme essentiellement d’origine virale, ne conduit pas à la mise en place d’une antibiothérapie. Le traitement préconisé fait donc appel à une approche locale associant anesthésiques et antiseptiques. Dans ce cadre, les pastilles ont une place prépondérante avec un relargage immédiat important et une persistance de la molécule au site. L’objectif de ce travail est de démontrer in vitro l’efficacité antimicrobienne des pastilles Drill®à court et long termes vis-à-vis des principaux pathogènes des infections ORL.

AbstractThe structure of the secretory tissues and the essential oil of the leaves of Croton campestrisSt Hil. were studied. The oil isolated by hydrodistillation was analyzed by GC and GC/MS and was found to contain 75 components accounting for 92.9% of the total oil, with the major components being caryophyllene oxide (29.9%) and humulene oxide II (8.0%). Growth inhibitory activity of the active compounds in solution was evaluated by measuring Minimal Inhibitory Concentration using a broth micro-method. The Minimal Inhibitory Concentration of the leaf oil was 1.56 µg/mL for Staphylococcus aureus, 6.25 µg/mL for Enterrococcus hiraeand 6.25 µg/mL for Candida albicans.

A comprehensive surface displacement monitoring system installed in the recently deglaciated bedrock slopes of the Aletsch Valley shows systematic reversible motions at the annual scale. We explore potential drivers for this deformation signal and demonstrate that the main driver is pore pressure changes of groundwater in fractured granitic mountain slopes. The spatial pattern of these reversible annual deformations shows similar magnitudes and orientations for adjacent monitoring points, leading to the hypothesis that the annually reversible deformation is caused by slope‐scale groundwater elevation changes and rock mass properties. Conversely, we show that the ground reaction to infiltration from snowmelt and summer rainstorms can be highly heterogeneous at local scale, and that brittle‐ductile fault zones are key features for the groundwater pressure‐related rock mass deformations. We also observe irreversible long‐term trends (over the 6.5 years data set) of deformation in the Aletsch valley composed of a larger uplift than observed at our reference GNSS station in the Rhone valley, and horizontal displacements of the slopes towards the valley. These observations can be attributed respectively to the elastic bedrock rebound in response to current glacier mass downwasting of the Great Aletsch Glacier and gravitational slope deformations enabled by cyclic groundwater pressure‐related rock mass fatigue in the fractured rock slopes. Mountain ranges are subject to deformation due to tectonic forces, orogenesis, erosion, and gravity. Other factors can deform the slopes, such as atmospheric‐driven thermal expansion and contraction, freeze‐thaw in open fractures, and pore pressure variations. Close to retreating glaciers, the mechanical unloading of the ice body, and rapidly changing thermal and hydrologic conditions lead to deformation of the slopes. The difficulty resides in identifying the different factors contributing to the total deformation. We track surface displacements of fractured crystalline rock slopes adjacent to the Great Aletsch Glacier (Switzerland) tongue for more than six years at unprecedentedly high spatial and temporal resolutions. Our results demonstrate that groundwater is a critical driver of deformation. Centimetric reversible outward displacements are observed after the snowmelt season each year, followed by a seasonal recession to which are superimposed displacements caused by heavy rainfall‐recharge events. Fault zones can be key features where most of the hydromechanical deformation occurs, and their geometry can control the direction of deformation. Glacier melting induces long‐term trends of deformation. In addition, annual pore‐pressure cycles lead to hydromechanical fatigue processes. This work opens a new vision on the spatial and temporal variability of processes responsible for bedrock deformation in paraglacial mountain slopes. Seasonal pore pressure variations in fractured crystalline hillslope induce correlated reversible surface deformationsDecameter‐scale brittle‐ductile faults control local spatial variations of deformation patternsCyclic groundwater pressure‐related rock mass fatigue induces irreversible gravitationally driven displacements in valley slopes Seasonal pore pressure variations in fractured crystalline hillslope induce correlated reversible surface deformations Decameter‐scale brittle‐ductile faults control local spatial variations of deformation patterns Cyclic groundwater pressure‐related rock mass fatigue induces irreversible gravitationally driven displacements in valley slopes

Heterotrimeric G-proteins, comprising G, G, and G subunits, are molecular switches that regulate numerous signaling pathways involved in cellular physiology. This characteristic is achieved by the adoption of two principal states: an inactive state in which GDP-bound G is complexed with the G dimer, and an active state in which GTP-bound G is freed of its G binding partner. Structural studies have illustrated the basis for the distinct conformations of these states which are regulated by alterations in three precise ‘switch regions’ of the G subunit. Discrete differences in conformation between GDP- and GTP-bound G underlie its nucleotide-dependent protein-protein interactions (e.g., with G/receptor and effectors, respectively) that are critical for maintaining their proper nucleotide cycling and signaling properties. Recently, several screening approaches have been used to identify peptide sequences capable of interacting with G (and free G) in nucleotide-dependent fashions. These peptides have demonstrated applications in direct modulation of the nucleotide cycle, assessing the structural basis for aspects of G and G signaling, and serving as biosensor tools in assays for G activation including high throughput drug screening. In this review, we highlight some of the methods used for such discoveries and discuss the insights that can be gleaned from application of these identified peptides.

Between February 2001 and March 2003, 17 patients from the neurosurgery department of the University Hospital of Rangueil (Toulouse, Southern France) developed Serratia liquefaciens infections. Due to the atypical antibiotype displayed by the clinical isolates (i.e. gentamicin resistance), an outbreak was suspected. Molecular analysis carried out by pulsed-field gel electrophoresis demonstrated a genetic link for all patients. Furthermore, the patient who introduced the epidemic Serratia strain was also identified and shown to be related to the two epidemic peaks observed during the outbreak period. Investigation failed to reveal a reservoir among the antiseptics and soaps, or among the mechanical ventilators used. However, when the colonization of patients was investigated, positive carriage was observed and could be considered as a potential risk for the spread of the epidemic strain. Due to the delay between antibiotherapy and S. liquefaciens colonization, a selection effect had to be considered. Finally, implementation of hygiene measures was accompanied by control of the outbreak.

Current methods of measuring changes in the thickness of scarred tissue are prone to error, making it hard to assess the effectiveness of treatment. PRIMOS is a digital system that makes accurate measurements of three-dimensional images.

ABSTRACTThe resistance of bacterial biofilms to physical and chemical agents is attributed in the literature to various interconnected processes. The limitation of mass transfer alters the growth rate, and physiological changes in the bacteria in the film also appear. The present work describes an approach to determination of the mechanisms involved in the resistance of bacteria to quaternary ammonium compounds (benzalkonium chloride) according to the C-chain lengths of those compounds. For Pseudomonas aeruginosaCIP A 22, the level of resistance of the bacteria in the biofilm relative to that of planktonic bacteria increased with the C-chain length. For cells within the biofilm, the exopolysaccharide induced a characteristic increase in surface hydrophilicity. However, this hydrophilicity was eliminated by simple resuspension and washing. The sensitivity to quaternary ammonium compounds was restored to over 90%. Staphylococcus aureusCIP 53 154 had a very high level of resistance when it was in the biofilm form. A characteristic of bacteria from the biofilm was a reduction in the percent hydrophobicity, but the essential point is that this hydrophobicity was retained after the biofilm bacteria were resuspended and washed. The recovery of sensitivity was thus only partial. These results indicate that the factors involved in biofilm resistance to quaternary ammonium compounds vary according to the bacterial modifications induced by the formation of a biofilm. In the case of P. aeruginosa, we have underlined the involvement of the exopolysaccharide and particularly the three-dimensional structure (water channels). In the case of S. aureus, the role of the three-dimensional structure is limited and drastic physiological changes in the biofilm cells are more highly implicated in resistance.

The aim of this study was to determine the performances of methods used for the neonatal diagnosis of congenital toxoplasmosis. We included 165 pregnant women infected during pregnancy over a 10-year period. Fifty-seven cases of congenital toxoplasmosis were demonstrated (34.5%). Neonatal diagnosis gave positive results in 50 cases (88%). Parasites were isolated from placenta or cord blood in 61% of the infected newborns, more frequently from placenta (60%) than from cord blood (43%). This method was the only criterion of infection in 18% of these infected infants. The detection of specific IgM and IgA antibodies performed on 42 sera of infected infants allowed the diagnosis of congenital infection in 34 cases (81%). IgA antibodies were more frequently detected (60%) than specific IgM (50%). Neonatal and prenatal screening were carried out for 143 pregnant women. This combination diagnosed 39 of 40 infected infants (98%). Prenatal diagnosis identified 30 of 40 cases (75%). Nine cases were diagnosed through neonatal screening and one case with the postnatal follow-up. When prenatal diagnosis was positive, pyrimethamine and sulfadoxine were administered to the mothers (25 cases) in addition to spiramycin. Toxoplasma gondiiwas less frequently isolated in the placenta and the cord blood of these women (32% and 19%, respectively) than in women treated by spiramycin alone (83% and 63%) proving the antiparasitic action of these drugs. In conclusion, neonatal screening combining parasite detection in placenta and immunological methods on cord blood is essential particularly when prenatal diagnosis is negative. Therefore, when this diagnosis is positive, a treatment with pyrimethamine and sulfamide can be started in the first month of life.

The activity of 19 antibiotics and four antiseptics and/or disinfectants was studied against 138 non-redundant strains of Aeromonas spp. (104 Aeromonas caviae, 22 Aeromonas sobria and 12 Aeromonas hydrophila) isolated from two European rivers. Antibiotic resistance frequencies were: nalidixic acid, 59%; tetracycline, 14%; fosfomycin, 8%; tobramycin and cotrimoxazole, 7%; cefotaxime, 4%; chloramphenicol, 2%; gentamicin, 1%. Most of the nalidixic acid-resistant strains were susceptible to fluoroquinolones (54-98%). Antibiotic resistance rates varied according to the source of the strains. All Aeromonas spp. strains were killed by 50 ppm of chlorine, cetylpyridinium chloride and peracetic acid, and by 1600 ppm of glutaraldehyde.

The bactericidal activity of a pulsed fibre-optic Nd-YAP laser on various strains of oral bacteria: Prevotella nigrescens, Streptococcus sanguis, Actinomyces viscosus(i), Fusobacterium nucleatum, Actinobacillus actinomycetemcomitansand Peptostreptococcus micros(i) was evaluated. A 200-μm optical fibre was placed in Eppendorf tubes containing the different bacterial suspensions. At an energy of 170 mJ/30 Hz, 351 pulses of 150 μs were sufficient to kill the most resistant bacteria (i). The exposure time was 28 s. The temperature rise caused by the shots were measured in vitro at the surface of the roots of two groups of 10 single-rooted teeth. One group received 350 pulses; for the other the preparation time was fixed at 28 s. The temperature rose by 25.66°C for the first group and 25.25°C for the second.

We screened about a hundred microorganisms (including unidentified yeasts, fungi, and bacteria) for their ability to produce xylanolytic enzymes. About 40 of them were hemicellulolytic; among these, we selectedPenicillium canescens 10- 10cfor detailed study because of its ability to produce an interesting enzymatic complex in quantity. The xylanase complex was cellulase-free, and had an optimal activity at pH 4.6–5.0 and 55–60‡C on birchwood xylan.

Oral ‘Ribomunyl’ has been shown to increase levels of specific salivary IgA. The ability of specific salivary IgA to inhibit the adhesion of Streptococcus pneumoniaeto buccal epithelial cells was investigated in vitrousing 13 saliva samples from healthy volunteers who received ‘Ribomunyl’ therapy for 3 weeks. The S. pneumoniaestrain contained in ‘Ribomunyl’ was [3H]thymidine-labelled and pretreated with dilutions of saliva for 1 hour at 37°C. Bacterial adhesion was measured after 2 hours’ contact with human oral epidermal cell monolayers at 37° under CO2. Nonadherent bacteria were washed off, and the residual radioactivity of the monolayers was compared with that of bacteria not pretreated with saliva. A significant decrease (p < 0.05) in S. pneumoniaeadhesion was observed with 6 saliva samples with high levels of specific IgA. This decrease was seen at all dilutions from 1/5 to 1/1000. In contrast, no significant modification of adhesion was seen in the 7 saliva samples with unmodified levels of IgA. These data demonstrate that the increase in salivary IgA levels during ‘Ribomunyl’ therapy was linked with the capacity of saliva samples to specifically and efficiently inhibit adhesion of S. pneumoniaeto buccal epithelial cells in vitro.

In the singlet state phosphenium cations feature both a vacant orbital and a lone pair at the phosphorus center (1). The anticipated amphoterism property of these species can be used for the synthesis of unusual heterocyclic derivatives. Our interest (2) in this type of chemistry bring us to report the reactions of stable phosphenium ions with unsaturated organic reactives i.e imines, a diimines, amidines and isocyanides.

Recession analysis is widely used for characterizing aquifer and basin properties based on the falling limb of the hydrograph. However, recession analysis using streamflow discharge requires a relationship (the rating curve) between simultaneous measurements of water height, h, and discharge, Q, across a wide range of flows, which is expensive to obtain, and changes in time. We leverage the relationship between hand Q(typical power law) to perform recession analysis using hdirectly, thus permitting identification of transient flow regimes, where only his available. Recession analysis evaluates the rate of change in discharge, −dQ/dt, as a function of discharge, Q, in a bilogarithmic plot where the slope, b, contains information about aquifer characteristics. While values of bare not conserved when replacing Qwith h, we find that the variability in values of bwithin and between events is captured in recession analysis for both Qand h. For example, when considering individual recessions from a large number of watersheds, a change from a smaller bat high discharge/stage to a larger bat lower discharge/stage occurs in most watersheds and suggests a transition to a more long‐lasting, and less drought‐sensitive, baseflow regime. With the advent of low‐cost reliable pressure loggers, as well as satellites that provide global reporting of river stage, recession analysis using water height expands the number of river systems where recession analysis can be conducted and provides the potential for insights into the variability of watershed drainage characteristics without the need for a discharge record. Using water height in place of discharge for recession analysis preserves general characteristics of the recession curveAn analytical expression equating the power law exponents of water height and discharge is given when the rating curve is a power lawThe ratio of power law exponents for individual recessions at high and low water heights can identify a transition in streamflow regimes

Cross‐hole fluid injection tests were performed on shallow (0.5 km depth) crustal fault zones to characterize their internal flow structures on scales of 3–30 m. The data were acquired at the Grimsel Rock Laboratory, Switzerland, after the zonal isolation of damage zones in boreholes equipped with multipacker systems. We show that 80% of the pressure responses detected evolved as a power function of time due to fracture‐controlled flow and were best described by a fractional model with a flow dimension (n) in the range of [1.3,1.5]. The scaling of characteristic times (tc) and intermediate transitions in the flow dimension is shown to be inconsistent with the trend expected for normal diffusion, indicating a diffusion slowdown process caused by the spatial integration of structurally different damage zones. An analysis of the entire data set points to a subdiffusive regime where the mean squared displacement of pressure fronts, ⟨r2(t)⟩, scales as ⟨r2(t)⟩∝t0.59, similar to an anomalous diffusion process on synthetic fractal systems. We characterize this diffusion slowdown by calculating a network connectivity exponent (θ) of 1.4, from which we estimate a fractal dimension of df=2.23 for the tested fault zones. Such a value close to 2.0 supports the view of fault damage zones as hierarchical systems promoting flow channeling. Our results provide further support to theoretical models of fractional flow and their application to fractured media in nature. We report direct, high‐resolution observations of pressure diffusion from fluid injection tests in shallow crustal fault zonesFractional flow regimes systematically emerge in response to spatial integration of structurally different damage zones during injectionThe fractal structure of damage zones may explain the emergence of anomalously slow pressure diffusion around faults

New in situ measurements to constrain the range, distribution, and spatial (meter‐scale) variations of permeability in shallow crustal fault zones are reported based on systematic downhole tests at 0.5‐km depth in crystalline rock. Single and cross‐hole hydraulic packer tests were performed at a new dedicated test facility hosted in the Grimsel Test Site, in the Swiss Alps, following the technical instrumentation and isolation of discrete fault zones accessed by an array of boreholes. Single‐hole test results are presented in this paper, while cross‐hole experiments are reported in the companion paper. Our results reveal a sharp spatial falloff in permeability, from 10‐13to 10‐21m2, with off‐fault distances of 1–5 m and characterized by a power‐law relation with fracture density. Fractures linking subparallel faults were detected as high‐permeability discrete spots several meters away from off‐fault damage. Due to the narrow (centimeter‐wide) thickness of fault cores, the hydraulic tests presented in this study do not characterize the permeability of fault core materials. The transmissivity of single fractures spans six orders of magnitude (10‐12to 10‐6m2/s) and is systematically higher in damage zones. In situ stresses appear to have a minor effect on natural, present‐day fracture transmissivity at the borehole scale. We suggest that the geometrical and topological properties of fracture systems instead tend to control the permeability of the shallow crustal faults studied. We mapped permeability variations across shallow crustal fault zones through systematic downhole pressure pulse testsA sharp permeability decay up to eight orders of magnitude with off‐fault distance is observedGeometry and topology exert a dominant control on the permeability of fracture systems in shallow crustal settings

Treatment of the chlorophosphaalkene (Ia) or the chlorophosphaimine (Ib) with the N‐silylimines (II) for only a few minutes produces the (di)aza(di)phosphadienes (III).

The phosphenium salts (I) react with the iminophosphane (II) to give the diazaphosphetidines (III) which are converted to the phosphonium triflates (V).

Treatment of the bissilyldichlorophosphine (I) with the N‐silylated phenylamidine (II) results in cyclization, producing the diazadiphospholene (III).

Cyclocondensation of the phosphenium salts (I) with the isocyanides (II) yields in general the 1‐aza‐3‐phosphetine salts (III) and (IV) as the main products.