Operando Spectroscopic Investigation of the ReO.2HO Adduct obtained by Controlled Hydration of ReO.

We provide here a comprehensive investigation spectroscopic of the controlled hydration of ReO using Raman, Fourier-Transform Infrared (FTIR) and X-Rays Absorption (XAS) techniques in complement with ab initio modelling for confirming the spectral assignments. Hence, the Raman signature of ReO.2HO was obtained, and the evolution kinetics was investigated to provide a detailed description of the hydration process.

Characterizing the ZrC(111)/-ZrO(111) Hetero-Ceramic Interface: First Principles DFT and Atomistic Thermodynamic Modeling.

The mechanical and physical properties of zirconium carbide (ZrC) are limited to its ability to deteriorate in oxidizing environments. Low refractory oxides are typically formed as layers on ZrC surfaces when exposed to the slightest concentrations of oxygen. However, this carbide has a wide range of applications in nuclear reactor lines and nozzle flaps in the aerospace industry, just to name a few.

Patient's Perspective on Using Mobile Technology as an Aid to Psychotherapy.

This piece draws from a patient's perspective on his treatment using mobile health technology in conjunction with weekly group and individual psychotherapy. Research has demonstrated that using telepsychology as part of mental health treatment shows great promise to help advance the field of psychotherapy. Using mobile health technology such as mobile phone apps allows for collaboration with patients and their providers.

Stability, equilibrium morphology and hydration of ZrC(111) and (110) surfaces with H₂O: a combined periodic DFT and atomistic thermodynamic study.

ZrC is a non-oxide ultra-high temperature ceramic (UHTC) material with excellent physical and mechanical properties used in nuclear plants and jet propulsion engines. However, the mechanical properties can be lost because of the easy oxidation of its grain surfaces. One way of dealing with such a problem is to coat the surface with inert carbides like SiC which can be grafted onto the ZrC surface by first modifying the exposed surfaces with reactive molecules.

Extended Czjzek model applied to NMR parameter distributions in sodium metaphosphate glass.

The extended Czjzek model (ECM) is applied to the distribution of NMR parameters of a simple glass model (sodium metaphosphate, NaPO3) obtained by molecular dynamics (MD) simulations. Accurate NMR tensors, electric field gradient (EFG) and chemical shift anisotropy (CSA) are calculated from density functional theory (DFT) within the well-established PAW/GIPAW framework. The theoretical results are compared to experimental high-resolution solid-state NMR data and are used to validate the considered structural model.

Fine hierarchy of the V-O bonds by advanced solid state NMR: novel Pb4(VO2)(PO4)3 structure as a textbook case.

We report here a complete structural characterization of a new lead Pb(4)(VO(2))(PO(4))(3) vanadophosphate compound by single crystal X-ray diffraction and (51)V and (31)P solid-state NMR spectroscopy. Although structural data are commonly used for the estimation of bond lengths and further delimitation of the true coordination number (e.g.

Structure of clean and hydrated α-Al2O3 (1102) surfaces: implication on surface charge.

Periodic DFT calculations coupled to a first-principle thermodynamic approach have allowed us to establish a surface phase diagram for the different terminations of the α-Al(2)O(3) (1102) surface in various temperature and water pressure conditions. Theoretical results are compared with previous experimental data from the literature. Under a wide range of temperature and water pressure (including ambient conditions) the most stable surface (denoted C2_1H(2)O in this work) is terminated with singly coordinated hydroxyls on four-fold coordinated aluminium (Al(4C)-μ(1)-OH) while most existing surface models are only considering six-fold coordinated surface Al atoms as in the bulk structure of alumina.

An easily accessible Re-based catalyst for the selective conversion of methanol: evidence for an unprecedented active site structure through combined operando techniques.

Heterogeneous Re/SiO(2) catalysts prepared using a one pot sol-gel synthesis were found to display high activity in the direct, selective methanol conversion to methylal, which is correlated to an unprecedented rhenium oxide structure.

First-principles calculations of NMR parameters for phosphate materials.

In this short review, we discuss the ability to reproduce NMR parameters in the case of phosphates materials through electronic structure calculation within density functional theory linear response. Indeed, the gauge-including projector-augmented wave is today largely used by the solid-state NMR community as a tool for structural determination and it has been applied to a large variety of materials. We emphasise on the crucial points that should be taken into account to perform such calculations.

New insights into oxygen environments generated during phosphate glass alteration: a combined 17O MAS and MQMAS NMR and first principles calculations study.

In the present study, we used a combination of (17)O NMR methods at a high magnetic field with first-principles calculations in order to characterize the oxygen sites in a series of hydroxylated sodium phosphate compounds, namely the hydrogen pyrophosphate Na(2)H(2)P(2)O(7) and the hydrogen orthophosphates NaH(2)PO(4), NaH(2)PO(4) x H(2)O and NaH(2)PO(4) x 2 H(2)O. The chemical shifts and quadrupolar parameters of these compounds were interpreted in terms of local and semi-local environment, i.e.

Prevalence of granular corneal dystrophy type 2 (Avellino corneal dystrophy) in the Korean population.

Purpose: This study investigates the prevalence of granular corneal dystrophy type 2 (GCD2; Avellino corneal dystrophy) in the Korean population.

Methods: GCD2 homozygotes were identified through a collaboration of Korean referral centers for corneal disease. The genetic status of the patients and their immediate families were verified by DNA analysis.

Bilateral acute angle-closure associated with systemic lymphoma: a report of 2 cases.

Bilateral acute angle-closure is a rare occurrence. When the central anterior chambers are shallow, it is often associated with systemic disease. We present 2 patients with atypical bilateral acute angle-closure as the presentation of systemic lymphoma.

Indirect detection via spin-1/2 nuclei in solid state NMR spectroscopy: application to the observation of proximities between protons and quadrupolar nuclei.

We present a comprehensive comparison of through-space heteronuclear correlation techniques for solid state NMR, combining indirect detection and single-channel recoupling method. These techniques, named D-HMQC and D-HSQC, do not suffer from dipolar truncation and can be employed to correlate quadrupolar nuclei with spin-1/2 nuclei. The heteronuclear dipolar couplings are restored under magic-angle spinning by applying supercycled symmetry-based pulse sequences (SR412) or simultaneous frequency and amplitude modulation (SFAM).

17O solid-state NMR and first-principles calculations of sodium trimetaphosphate (Na3P3O9), tripolyphosphate (Na5P3O10), and pyrophosphate (Na4P2O7).

The assignment of high-field (18.8 T) (17)O MAS and 3QMAS spectra has been completed by use of first-principles calculations for three crystalline sodium phosphates, Na 3P 3O 9, Na 5P 3O 10, and Na 4P 2O 7. In Na 3P 3O 9, the calculated parameters, quadrupolar constant ( C Q), quadrupolar asymmetry (eta Q), and the isotropic chemical shift (delta cs) correspond to those deduced experimentally, and the calculation is mandatory to achieve a complete assignment.

Amorphous oxide as a novel efficient catalyst for direct selective oxidation of methanol to dimethoxymethane.

We report for the first time the use of an amorphous oxide catalyst for the selective oxidation of methanol in the gas phase, leading at 553 K to the production of dimethoxymethane with a selectivity as high as 90% at high methanol conversion (68%).

Homozygous granular corneal dystrophy type II (Avellino corneal dystrophy): natural history and progression after treatment.

Purpose: To describe the clinical features of homozygous granular corneal dystrophy type II (GCDII) with age and with several kinds of treatment in 18 homozygous patients in several different conditions.

Methods: Eighteen homozygous GCDII patients, confirmed with DNA analysis, of 13 families were enrolled. Their clinical features that include age at detection by parents, visual acuity, and disease progression were evaluated.

Impact of short-term exposure of commercial eyedrops preserved with benzalkonium chloride on precorneal mucin.

Purpose: The aim of this study is to investigate the short-term effects of benzalkonium chloride (BAC), a preservative used in many ophthalmic topical solutions, on precorneal mucin in humans.

Methods: Immortalized human corneal-limbal epithelial (HCLE) cells were exposed to eyedrops containing BAC solutions at 0.0025% and 0.

Amniotic membrane as a biologic pressure patch for treating epithelial ingrowth under a damaged laser in situ keratomileusis flap.

We present 2 patients who had epithelial ingrowth after intraoperative laser in situ keratomileusis (LASIK) complications that created defects in the flap near the visual axis. As an adjuvant to removing the epithelium, an amniotic membrane patch was sutured tightly to the episclera so that it covered the entire cornea. The amniotic membrane overlay was left in place for about 1 week.

CO adsorption on CoMo and NiMo sulfide catalysts: a combined IR and DFT study.

Experimental IR spectra of carbon monoxide adsorbed on a series of Mo/Al2O3, CoMo/Al2O3, and NiMo/Al2O3 sulfided catalysts have been compared to ab initio DFT calculations of CO adsorption on CoMo and NiMo model surfaces. This approach allows the main IR features of CO adsorbed on the sulfide phase to be assigned with an uncertainty of 15 cm(-1). On the CoMo system, the band at 2070 cm(-1) is specific of the promotion by Co and is assigned to CO interacting either with a Co atom or with a Mo atom adjacent to a Co atom.

A new experimental cell for in situ and operandoX-ray absorption measurements in heterogeneous catalysis.

A new X-ray absorption cell dedicated to in situ and operando experiments in heterogeneous catalysis has been built and tested. The cell consists of several boron nitride and stainless steel plates linked together using graphite seals. It allows the measurement of XANES and EXAFS spectra of heterogeneous catalysts within a wide range of photon energies in transmission mode under the flow of various oxidative and reductive gas mixtures at elevated temperatures.

Rates of epithelial ingrowth after LASIK for different excimer laser systems.

Purpose: To investigate the incidence of epithelial ingrowth after laser in situ keratomileusis (LASIK) using the VISX 20/20B and VISX Star S3 laser systems.

Methods: A chart review of patients who had undergone LASIK between April 1999 and December 2001 was performed. Patients having known risk factors for epithelial ingrowth were excluded from the study.

Simulation of the embryonic stage of ZnS formation from aqueous solution.

We investigate the processes of cluster formation and growth of ZnS from aqueous solution using molecular dynamics simulation techniques. The influence of both temperature and concentration is studied. We show that, at lower temperatures, the crucial process is the transformation of an outer-sphere Zn/S complex to an inner-sphere ion pair.

Quantifying DNA concentrations using fluorometry: a comparison of fluorophores.

Detection of low concentrations of DNA is important in vision research because many animal models only provide scant samples of ocular tissue. Quantitative analysis of low concentrations of double stranded DNA is now feasible using fluorometry with newer fluorophores. This technique offers a rapid way to evaluate the DNA content of samples based on the measurement of fluorescence enhancement emitted by fluorophore-bound DNA and is more sensitive than absorption spectrometry.

Hydrogen activation on Mo-based sulfide catalysts, a periodic DFT study.

Hydrogen adsorption on Mo[bond]S, Co[bond]Mo[bond]S, and Ni[bond]Mo[bond]S (10 1 macro 0) surfaces has been modeled by means of periodic DFT calculations taking into account the gaseous surrounding of these catalysts in working conditions. On the stable Mo[bond]S surface, only six-fold coordinated Mo cations are present, whereas substitution by Co or Ni leads to the creation of stable coordinatively unsaturated sites. On the stable MoS(2) surface, hydrogen dissociation is always endothermic and presents a high activation barrier.