From Venous to Arterial Blood in the Same Tunneled Dialysis Catheter After Starting a Continuous Renal Replacement Therapy: A Case Report.

Tunneled dialysis catheter is the alternative for dialysis patients who cannot benefit from an arteriovenous fistula. The insertion of such catheters is usually ultrasound-guided to prevent complications. A 36-year old patient had an unexpected complication following the insertion of a right femoral tunneled dialysis catheter: Although the blood collected from the catheter was venous after insertion, the blood turned arterial few minutes after initiating a continuous renal replacement therapy (CRRT).

Broadly neutralizing humanized SARS-CoV-2 antibody binds to a conserved epitope on Spike and provides antiviral protection through inhalation-based delivery in non-human primates.

The COVID-19 pandemic represents a global challenge that has impacted and is expected to continue to impact the lives and health of people across the world for the foreseeable future. The rollout of vaccines has provided highly anticipated relief, but effective therapeutics are required to further reduce the risk and severity of infections. Monoclonal antibodies have been shown to be effective as therapeutics for SARS-CoV-2, but as new variants of concern (VoC) continue to emerge, their utility and use have waned due to limited or no efficacy against these variants.

Direct Aspiration versus Combined Technique for Distal Medium-Vessel Occlusions: Comparison on a Human Placenta Model.

Background And Purpose: Mechanical thrombectomy appears to be a promising option for distal medium-vessel occlusions, for which intravenous thrombolysis is effective but may be insufficient when used alone. This study aimed to determine the optimal technique for these distal mechanical thrombectomies using the human placenta model.

Materials And Methods: Twenty-four procedures were performed, allowing comparison of direct aspiration ( = 12) versus the combined technique ( = 12).

Highlights on the reversible nonpolar-to-polar 321-3 phase transition at low temperature in NaLa(SO)·HO: mechanism and piezoelectric properties.

We report the existence in NaLa(SO)·HO of a displacive phase transition under 200 K from the nonpolar 321 to the polar 3 space group. This phase transition was predicted by density functional theory based calculations and experimentally confirmed from infrared spectroscopy and X-ray diffraction. The polar irreducible representation is the primary order parameter.

Preparation of Confined One-Dimensional Boron Nitride Chains in the 1-D Pores of Siliceous Zeolites under High-Pressure, High-Temperature Conditions.

Low-dimensional boron nitride (BN) chains were prepared in the one-dimensional pores of the siliceous zeolites theta-one (TON) and Mobil-twelve (MTW) by the infiltration, followed by the dehydrocoupling and pyrolysis of ammonia borane under high-pressure, high-temperature conditions. High-pressure X-ray diffraction in a diamond anvil cell and in a large-volume device was used to follow in situ these different steps in order to determine the optimal conditions for this process. Based on these results, millimeter-sized samples of BN/TON and BN/MTW were synthesized.

Extreme structural stability of TiSnO nanoparticles: synergistic effect in the cationic sublattice.

TiSnO nanoparticles (∼5 nm and ∼10 nm) have been studied under high pressure by Raman spectroscopy. For particles with diameter ∼10 nm, a transformation has been observed at 20-25 GPa while for particles with ∼5 nm diameter no phase transition has been observed up to ∼30 GPa. The TiSnO solid solution shows an extended stability at the nanoscale, both of its cationic and anionic sublattices.

[A rare but increasing aetiology of febrile dyspnea in the elderly].

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic infectious disease well described in patients living with HIV (PLHIV) but that can occur in other immunosuppressed patients. Currently, its incidence decreases in PLHIV but increases in non-HIV immunosuppressed patients, particularly in case of hematological diseases. Thus, in elderly, the diagnosis of PJP should be evoked in case of subacute pneumonia rapidly evolving to an acute respiratory distress, with or without interstitial pneumonia at chest radiography, and a context of immunosuppression.

Encapsulation effect of π-conjugated quaterthiophene on the radial breathing and tangential modes of semiconducting and metallic single-walled carbon nanotubes.

We developed a hybrid approach, combining the density functional theory, molecular mechanics, bond polarizability model and the spectral moment's method to compute the nonresonant Raman spectra of a single quaterthiophene (4T) molecule encapsulated into a single-walled carbon nanotube (metallic or semiconducting). We reported the optimal tube diameter allowing the 4T encapsulation. The influence of the encapsulation on the Raman modes of the 4T molecule and those of the nanotube (radial breathing modes and tangential modes) are analyzed.

Nonresonant Polarized Raman Spectra Calculations of Nitrogen-Doped Single-Walled Carbon Nanotubes: Diameter, Chirality, and Doping Concentration Effects.

Raman spectra of nitrogen-doped single-walled carbon nanotubes are calculated using the spectral moment's method combined with the bond polarizability model. The influence of the nanotube diameter and chirality is investigated. We also address the important question of the effect of the -doping concentration, and we propose an equation to estimate the doping concentration from the knowledge of the tube diameter and the frequency of the radial breathing mode.

Effect of Extra-Framework Cations on Negative Linear Compressibility and High-Pressure Phase Transitions: A Study of KCd[Ag(CN)].

The negative thermal expansion material potassium cadmium dicyanoargentate, KCd[Ag(CN)], is studied at high pressure using a combination of X-ray single-crystal diffraction, X-ray powder diffraction, infrared and Raman spectroscopy, and density functional theory calculations. In common with the isostructural manganese analogue, KMn[Ag(CN)], this material is shown to exhibit very strong negative linear compressibility (NLC) in the crystallographic direction due to structure hinging. We find increased structural flexibility results in enhanced NLC and NTE properties, but this also leads to two pressure-induced phase transitions-to very large unit cells involving octahedral tilting and shearing of the structure-below 2 GPa.

Infrared and Raman spectroscopy of non-conventional hydrogen bonding between N,N'-disubstituted urea and thiourea groups: a combined experimental and theoretical investigation.

The variety of H bond (HB) interactions is a source of inspiration for bottom-up molecular engineering through self-aggregation. Non-conventional intermolecular HBs between N,N'-disubstituted urea and thiourea are studied in detail by vibrational spectroscopies and ab initio calculations. Raman and IR mode assignments are given.

Pressure-Induced Sublattice Disordering in SnO_{2}: Invasive Selective Percolation.

SnO_{2} powders and single crystal have been studied under high pressure using Raman spectroscopy and ab initio simulations. The pressure-induced changes are shown to drastically depend on the form of the samples. The single crystal exhibits phase transitions as reported in the literature, whereas powder samples show a disordering of the oxygen sublattice in the first steps of compression.

Supramolecular organization of a H-bonded perylene bisimide organogelator determined by transmission electron microscopy, grazing incidence X-ray diffraction and polarized infra-red spectroscopy.

An organogelator based on a N,N'-substituted H-bonding perylenebisimide (PBI-C10) self-assembles to form either a green J-type (form I) or a red H-type (form II) aggregate structure. The molecular packing of both polymorphs was determined from a combination of Transmission Electron Microscopy (TEM) (low dose electron diffraction and high resolution), Grazing incidence X-ray diffraction and polarized infrared spectroscopy. To that aim, highly oriented films have been prepared by mechanical rubbing at controlled film temperature and DFT calculations were performed to identify representative vibrational IR bands and their associated polarizations.

12/14/14-Helix Formation in 2:1 α/β-Hybrid Peptides Containing Bicyclo[2.2.2]octane Ring Constraints.

The highly constrained β-amino acid ABOC induces different types of helices in β urea and 1:1 α/β amide oligomers. The latter can adopt 11/9- and 18/16-helical folds depending on the chain length in solution. Short peptides alternating proteinogenic α-amino acids and ABOC in a 2:1 α/β repeat pattern adopted an unprecedented and stable 12/14/14-helix.

High-temperature elastic moduli of flux-grown α-GeO2 single crystal.

From high-precision Brillouin spectroscopy measurements, six elastic constants (C11, C33, C44, C66, C12, and C14) of a flux-grown GeO2 single crystal with the α-quartz-like structure are obtained in the 298-1273 K temperature range. High-temperature powder X-ray diffraction data is collected to determine the temperature dependence of the lattice parameters and the volume thermal expansion coefficients. The temperature dependence of the mass density, ρ, is evaluated and used to estimate the thermal dependence of its refractive indices (ordinary and extraordinary), according to the Lorentz-Lorenz equation.

Thermodynamic properties of the α-quartz-type and rutile-type GeO2 from first-principles calculations.

Phonon density-of-states and related thermodynamic properties of the α-quartz-type and rutile-type germanium dioxide (GeO2) are investigated from density functional perturbation theory. The significant density-of-states at the low frequencies in the α-quartz-type GeO2 are at the origin of (i) its lower internal energy below 250 K, (ii) its smaller free energy, (iii) its higher entropy, (iv) its lower Debye temperature and (v) its larger positive linear thermal expansion, with respect to the rutile-type GeO2.

First-principles model potentials for lattice-dynamical studies: general methodology and example of application to ferroic perovskite oxides.

We present a scheme to construct model potentials, with parameters computed from first principles, for large-scale lattice-dynamical simulations of materials. We mimic the traditional solid-state approach to the investigation of vibrational spectra, i.e.

Vibrational origin of the thermal stability in the highly distorted α-quartz-type material GeO2: an experimental and theoretical study.

We report an experimental and theoretical vibrational study of the high-performance piezoelectric GeO2 material. Polarized and variable-temperature Raman spectroscopic measurements on high-quality, water-free, flux-grown α-quartz GeO2 single crystals combined with state-of-the-art first-principles calculations allow the controversies on the mode symmetry assignment to be solved, the nature of the vibrations to be described in detail, and the origin of the high thermal stability of this material to be explained. The low-degree of dynamic disorder at high-temperature, which makes α-GeO2 one of the most promising piezoelectric materials for extreme temperature applications, is found to originate from the absence of a libration mode of the GeO4 tetrahedra.

Investigation on the vibrational and structural properties of a self-structured bridged silsesquioxane.

The crystalline structure of ureidopyrimidinone-based silane (UPY) has been determined. The local and long range order structuring of the bridged silsesquioxane (MUPY) resulting from the sol-gel hydrolysis-condensation of the former precursor has been investigated by MFTIR (Mid Fourier Transform InfraRed) combined with DFT (Density Functional Theory) and XRD (X-ray diffraction) studies. These studies showed that a long range structuring exists within the organic fragments with the transcription of the DDAA (Donor-Donor-Acceptor-Acceptor) H-bonding array from UPY to MUPY whereas a disordered siloxane network was revealed in the hybrid material.

Vibrational origin of the thermal stability in the high-performance piezoelectric material GaAsO4.

Theoretical calculations and experiments show the absence of libration modes of the tetrahedra in GaAsO(4), the most α-quartz-type distorted material. In consequence, the degree of dynamic disorder at high temperature is very low, making GaAsO(4) of high interest for high-temperature applications. This paper shows the importance of the theoretical calculations of vibration in oxide materials.

Scanning tunneling microscopy simulations of nitrogen- and boron-doped graphene and single-walled carbon nanotubes.

We report on studies of electronic properties and scanning tunneling microscopy (STM) of the most common configurations of nitrogen- or boron-doped graphene and carbon nanotubes using density functional theory. Charge transfer, shift of the Fermi level, and localized electronic states are analyzed as a function of the doping configurations and concentrations. The theoretical STM images show common fingerprints for the same doping type for graphene, and metallic or semiconducting nanotubes.

First-principles study of the dynamical and nonlinear optical properties of urea single crystals.

Raman and infrared spectra of urea single crystals have been calculated using the density functional theory. This allowed us to assign the remaining experimental low-frequency phonon modes. Then, we have determined the sign of the second-harmonic nonlinear optical susceptibility coefficient in urea to be negative, clarifying a long debate in the literature.

Raman scattering intensities in BaTiO(3) and PbTiO(3) prototypical ferroelectrics from density functional theory.

Nonlinear optical susceptibilities and Raman scattering spectra of the ferroelectric phases of BaTiO(3) and PbTiO(3) are computed using a first-principles approach based on density functional theory and taking advantage of a recent implementation based on the nonlinear response formalism and the 2n+1 theorem. These two prototypical ferroelectric compounds were chosen to demonstrate the accuracy of the Raman calculation based both on their complexity and their technological importance. The computation of the Raman scattering intensities has been performed not only for the transverse optical modes, but also for the longitudinal optical ones.