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1.
Argillites are one of the geological formations studied by IRSN for their confining properties for isolation of radioactive wastes. One of the main objectives is the study of water transport through rocks with very low water content and very low hydraulic conductivity by modeling of natural tracer profiles. This paper presents the protocol developed for and applied to the acquisition of data for chloride content in interstitial water of the Toarcian argillites at the Tournemire site (Southern France). This protocol is based on laboratory diffusion experiments and on modeling. Experimental data obtained during the transient and steady-state parts of diffusion experiments enable, respectively, the assessment of the diffusion coefficient and the determination of Cl concentration in pore water. Using this protocol, profiles with depth for both of these data sets have been acquired along the geological sequence. Taking into account the present knowledge of the geological and hydrogeological history of the Tournemire massif, a conceptual model granting the main role for mass transport to diffusion has been proposed. According to this conceptual model, a one-dimensional numerical model was built for simulating the mass transport of chloride through the sedimentary column, over 53 Ma. The good agreement between experimental data and calculated values for both diffusion coefficients and concentrations of chloride confirms that diffusion is likely the main process for mass transport in the massif. This model was also tested with the deuterium content of interstitial water, applying variable concentrations at the aquifer system boundaries for reflecting the thermal dependency of isotopic composition in precipitation. These simulations also reveal the likely important role of heterogeneities, such as fractures, in the variability of tracer concentrations with regards to a simple diffusion profile.  相似文献   
2.
Proteomes are intricate. Typically, thousands of proteins interact through physical association and post-translational modifications (PTMs) to give rise to the emergent functions of cells. Understanding these functions requires one to study proteomes as "systems" rather than collections of individual protein molecules. The abstraction of the interacting proteome to "protein networks" has recently gained much attention, as networks are effective representations, that lose specific molecular details, but provide the ability to see the proteome as a whole. Mostly two aspects of the proteome have been represented by network models: proteome-wide physical protein-protein-binding interactions organized into Protein Interaction Networks (PINs), and proteome-wide PTM relations organized into Protein Signaling Networks (PSNs). Mass spectrometry (MS) techniques have been shown to be essential to reveal both of these aspects on a proteome-wide scale. Techniques such as affinity purification followed by MS have been used to elucidate protein-protein interactions, and MS-based quantitative phosphoproteomics is critical to understand the structure and dynamics of signaling through the proteome. We here review the current state-of-the-art MS-based analytical pipelines for the purpose to characterize proteome-scale networks.  相似文献   
3.
2D materials are considered for applications that require strong light-matter interaction because of the apparently giant oscillator strength of the exciton tra...  相似文献   
4.
Metal injection molding (MIM) is a near net shape manufacturing method that allows for the production of components of small to moderate size and complex shape. MIM is a cost-effective and flexible manufacturing technique that provides a large innovative potential over existing methods for the industry of implantable devices. Commercially pure titanium (CP-Ti) samples were machined to the same shape as a composite feedstock with titanium and polyoxymethylene, and these metals were injected, debinded and sintered to assess comparative biological properties. Moreover, we treated MIM-Ti parts with BIOCOAT®, BIODIZE® and BIOCER®, three different anodic oxidation techniques that treat titanium using acid, alkaline and anion enriched electrolytes, respectively. Cytocompatibility as well as morphological and chemical features of surfaces was comparatively assessed on each sample, and the results revealed that MIM-Ti compared to CP-Ti demonstrated a specific surface topography with a higher roughness. MIM-Ti and BIOCER® samples significantly enhanced cell proliferation, cell adhesion and cell differentiation compared to CP-Ti. Interestingly, in the anodization post-treatment established in this study, we demonstrated the ability to improve osseointegration through anionic modification treatment. The excellent biological response we observed with MIM parts using the injection molding process represents a promising manufacturing method for the future implantable devices in direct contact with bones.  相似文献   
5.
Delphine  Miroslav   《Automatica》2009,45(9):2074-2081
In a recent paper we presented the first adaptive control design for an ODE system with a possibly large actuator delay of unknown length. We achieved global stability under full state feedback. In this paper we generalize the design to the situation where, besides the unknown delay value, the ODE also has unknown parameters, and where trajectory tracking (rather than equilibrium regulation) is pursued.  相似文献   
6.
Bread wheat is the most widely cultivated crop worldwide, used in the production of food products and a feed source for animals. Selection tools that can be applied early in the breeding cycle are needed to accelerate genetic gain for increased wheat production while maintaining or improving grain quality if demand from human population growth is to be fulfilled. Proteomics screening assays of wheat flour can assist breeders to select the best performing breeding lines and discard the worst lines. In this study, we optimised a robust LC–MS shotgun quantitative proteomics method to screen thousands of wheat genotypes. Using 6 cultivars and 4 replicates, we tested 3 resuspension ratios (50, 25, and 17 µL/mg), 2 extraction buffers (with urea or guanidine-hydrochloride), 3 sets of proteases (chymotrypsin, Glu-C, and trypsin/Lys-C), and multiple LC settings. Protein identifications by LC–MS/MS were used to select the best parameters. A total 8738 wheat proteins were identified. The best method was validated on an independent set of 96 cultivars and peptides quantities were normalised using sample weights, an internal standard, and quality controls. Data mining tools found particularly useful to explore the flour proteome are presented (UniProt Retrieve/ID mapping tool, KEGG, AgriGO, REVIGO, and Pathway Tools).  相似文献   
7.
8.
This study examines the development of children's ability to express emotions in their human figure drawing. Sixty children of 5, 8, and 11 years were asked to draw "a man," and then a "sad", "happy," "angry" and "surprised" man. Expressivity of the drawings was assessed by means of two procedures: a limited choice and a free labelling procedure. Emotionally expressive drawings were then evaluated in terms of the number and the type of graphic cues that were used to express emotion. It was found that children are able to depict happiness and sadness at 8, anger and surprise at 11. With age, children use increasingly numerous and complex graphic cues for each emotion (i.e., facial expression, body position, and contextual cues). Graphic cues for facial expression (e.g., concave mouth, curved eyebrows, wide opened eyes) share strong similarities with specific "action units" described by Ekman and Friesen (1978) in their Facial Action Coding System. Children's ability to depict emotion in their human figure drawing is discussed in relation to perceptual, conceptual, and graphic abilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
A novel SiX–dipropargyl glycerol scaffold (X: H, F, or 18F) was developed as a versatile prosthetic group that provides technical advantages for the preparation of dimeric radioligands based on silicon fluoride acceptor pre‐ or post‐labeling with fluorine‐18. Rapid conjugation with the prosthetic group takes place in microwave‐assisted click conjugation under mild conditions. Thus, a bivalent homodimeric SiX–dipropargyl glycerol derivatized radioligand, [18F]BMPPSiF, with enhanced affinity was developed by using click conjugation. High uptake of the radioligand was demonstrated in 5‐HT1A receptor‐rich regions in the brain with positron emission tomography. Molecular docking studies (rigid protein–flexible ligand) of BMPPSiF and known antagonists (WAY‐100635, MPPF, and MefWAY) with monomeric, dimeric, and multimeric 5‐HT1A receptor models were performed, with the highest G score obtained for docked BMPPSiF: ?6.766 as compared with all three antagonists on the monomeric model. Multimeric induced‐fit docking was also performed to visualize the comparable mode of binding under in vivo conditions, and a notably improved G score of ?8.455 was observed for BMPPSiF. These data directly correlate the high binding potential of BMPPSiF with the bivalent binding mode obtained in the biological studies. The present study warrants wide application of the SiX–dipropargyl glycerol prosthetic group in the development of ligands for imaging with enhanced affinity markers for specific targeting based on peptides, nucleosides, and lipids.  相似文献   
10.
Xylose was dehydrated over (H+) mordenite, using a continuous two-liquid-phase (aqueous-toluene) plug-flow reactor at 260 °C and 55 atm, with 98% conversion rate, 98% furfural molar yield, and 98% furfural selectivity (results from the first pass). Furfural in toluene was hydrogenated over a Cu/Fe catalyst, at 252 °C (gas-phase), in a 99% conversion rate to give 2-methylfuran in a 98% yield (same activity maintained for a 20-h operation).  相似文献   
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