Role of local structural distortions in the variation of martensitic transformation temperature with / ratio in NiMnZ (Z = In, Sn or Sb) alloys.

NiMnZ (Z = In, Sn or Sb) undergo martensitic transformation with transformation temperature () scaling with the average valence electron per atom (/) ratio. However, the rate of increase of depends on the type of Z atom, with the slope of / curve increasing from Z = In to Z = Sb. Local structural distortions are believed to be the leading cause of martensitic transformation in these alloys.

Experimental and Theoretical Force Constants as Meaningful Indicator for Interatomic Bonding Characteristics and the Specific Case of Elemental Antimony.

Stable Sb exhibits a rhombohedral structure, often referred to as distorted primitive cubic, with each Sb atom having three short and three longer first neighbor bonds. However, this crystal structure can also be interpreted as being layered, putting emphasis on only three short first neighbor bonds. Therefore, temperature-dependent extended X-ray absorption fine structure (EXAFS) spectroscopy is carried out at the Sb K-edge in order to obtain more detailed information on local structural and vibrational properties.

MOG-IgG is rare in AQP4-IgG seronegative NMO phenotype in Brazil.

Background: Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disease most frequently characterized by a neuromyelitis optica (NMO) phenotype, comprising both simultaneous or sequential optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM). Symptoms of brainstem, diencephalic and cerebral involvement may also occur. While most NMOSD patients test positive for serum aquaporin-4 (AQP4) antibodies, some seronegative patients test positive for oligodendrocyte glycoprotein-IgG (MOG-IgG).

RefXAS: an open access database of X-ray absorption spectra.

Under DAPHNE4NFDI, the X-ray absorption spectroscopy (XAS) reference database, RefXAS, has been set up. For this purpose, we developed a method to enable users to submit a raw dataset, with its associated metadata, via a dedicated website for inclusion in the database. Implementation of the database includes an upload of metadata to the scientific catalogue and an upload of files via object storage, with automated query capabilities through a web server and visualization of the data and files.

Structure of Polaronic Centers in Proton-Intercalated WO Scheelite-Type Tungstates.

The studies of polaronic centers in a homologous series of scheelite-type compounds WO ( = Ca, Sr, Ba) were performed using the W L-edge and Sr K-edge X-ray absorption spectroscopy combined with the reverse Monte Carlo simulations, X-ray photoelectron spectroscopy (XPS), and first-principles calculations. Protonated scheelites HWO were produced using acid electrolytes in a one-step route at ambient conditions. The underlying mechanism behind this phenomenon can be ascribed to the intercalation of H into the crystal structure of tungstate, effectively resulting in the reduction of W to W, i.

The Development and Atomic Structure of Zinc Oxide Crystals Grown within Polymers from Vapor Phase Precursors.

Sequential infiltration synthesis (SIS), also known as vapor phase infiltration (VPI), is a quickly expanding technique that allows growth of inorganic materials within polymers from vapor phase precursors. With an increasing materials library, which encompasses numerous organometallic precursors and polymer chemistries, and an expanding application space, the importance of understanding the mechanisms that govern SIS growth is ever increasing. In this work, we studied the growth of polycrystalline ZnO clusters and particles in three representative polymers: poly(methyl methacrylate), SU-8, and polymethacrolein using vapor phase diethyl zinc and water.

The Risk of Reinfection or Primary Hepatitis E Virus Infection at a Liver Transplant Center in Brazil: An Observational Cohort Study.

The hepatitis E virus is a major etiological agent of chronic hepatitis in immunosuppressed individuals. Seroprevalence in the liver transplantation setting varies according to the seroprevalence of the general population in different countries. This was a prospective cohort study of liver transplant recipients in southeastern Brazil.

Machine learning-based morphological quantification of replicative senescence in human fibroblasts.

Although aging has been investigated extensively at the organismal and cellular level, the morphological changes that individual cells undergo along their replicative lifespan have not been precisely quantified. Here, we present the results of a readily accessible machine learning-based pipeline that uses standard fluorescence microscope and open access software to quantify the minute morphological changes that human fibroblasts undergo during their replicative lifespan in culture. Applying this pipeline in a widely used fibroblast cell line (IMR-90), we find that advanced replicative age robustly increases (+28-79%) cell surface area, perimeter, number and total length of pseudopodia, and nuclear surface area, while decreasing cell circularity, with phenotypic changes largely occurring as replicative senescence is reached.

Mobility restrictions during the COVID-19 pandemic and reduced outpatient HIV and syphilis testing in Brazil.

Background: In the initial phases of the COVID-19 pandemic, strategies adopted to reduce the dissemination of SARS-CoV-2 relied on non-pharmacological interventions, including physical distancing. Mobility restrictions affected the availability and quality of care for many health conditions, including sexually transmitted infections.

Objective: To investigate the impact of the COVID-19 pandemic mobility restriction on syphilis and HIV testing in outpatient settings.

An open access, machine learning pipeline for high-throughput quantification of cell morphology.

Cell morphology is influenced by many factors and can be used as a phenotypic marker. Here we describe a machine-learning-based protocol for high-throughput morphological measurement of human fibroblasts using a standard fluorescence microscope and the pre-existing, open access software ilastik for cell body identification, ImageJ/Fiji for image overlay, and CellProfiler for morphological quantification. Because this protocol overlays nuclei with their cell bodies and relies on coloration differences, it can be broadly applied to other cell types beyond fibroblasts.

High-resolution XEOL spectroscopy setup at the X-ray absorption spectroscopy beamline P65 of PETRA III.

A newly designed setup to perform steady-state X-ray excited optical luminescence (XEOL) spectroscopy and simultaneous XEOL and X-ray absorption spectroscopy characterization at beamline P65 of PETRA III is described. The XEOL setup is equipped with a He-flow cryostat and state-of-the-art optical detection system, which covers a wide wavelength range of 300-1700 nm with a high spectral resolution of 0.4 nm.

Distinct Immunological Profiles Help in the Maintenance of Salivary Secretory IgA Production in Mild Symptoms COVID-19 Patients.

Background: Relevant aspects regarding the SARS-CoV-2 pathogenesis and the systemic immune response to this infection have been reported. However, the mucosal immune response of the upper airways two months after SARS-CoV-2 infection in patients with mild/moderate symptoms is still not completely described. Therefore, we investigated the immune/inflammatory responses of the mucosa of the upper airways of mild/moderate symptom COVID-19 patients two months after the SARS-CoV-2 infection in comparison to a control group composed of non-COVID-19 healthy individuals.

Long term persistence of coronavirus SARS-CoV-2 infection.

During the COVID-19 pandemic, a case of a long-term persistence of SARS-CoV-2 infection (from March 26 to May 20, 2020) was identified at a private hospital in São Paulo, SP, Brazil. The long-term positivity for SARS-CoV-2 in reverse transcriptase polymerase chain reaction tests of a patient diagnosed with COVID-19 suggests, at least part of patients who recovered, may still carry and transmit the SARS-CoV-2 virus. This fact emphasizes the importance of having at least two negative reverse transcriptase polymerase chain reaction test results for SARS-CoV-2.

A hydrothermal apparatus for x-ray absorption spectroscopy of hydrothermal fluids at DESY.

We present a new autoclave that enables in situ characterization of hydrothermal fluids at high pressures and high temperatures at synchrotron x-ray radiation sources. The autoclave has been specifically designed to enable x-ray absorption spectroscopy in fluids with applications to mineral solubility and element speciation analysis in hydrothermal fluids in complex compositions. However, other applications, such as Raman spectroscopy, in high-pressure fluids are also possible with the autoclave.

Lattice assisted dielectric relaxation in four-layer Aurivillius BiFeTiOceramic at low temperatures.

We have investigated magnetic, structural and dielectric properties of BiFeTiO(BFTO) in the temperature range 5K-300 K. Using diffraction, Raman spectroscopy and x-ray absorption fine structure measurements, iso-structural modifications are observed at low temperatures (≈100 K). The analysis of dielectric constant data revealed signatures of dielectric relaxation, concomitant with these structural modifications in BFTO at the same temperatures.

Giant zirconium-bisphosphonate nano-ribbons and their liquid crystalline phase behaviour in water.

In decimolar aqueous solutions, zirconium oxychloride octahydrate forms several micrometer long and approximately 15 nm wide thin ribbons through the reaction with excess amounts of the sodium salt of 1-hydroxyethane-1,1-diphosphonic acid (HEDP, known as etidronic acid). Primarily deduced from SAXS, TEM, EXAFS and solid-state NMR analyses, a consistent structural model enables congruous explanations for the colloidal behaviour of the purified ribbons as well as of their reaction products with ammonia and amines, respectively. Properties of the lyotropic, liquid crystalline phases are discussed in the light of potential applications in aqueous coatings.

Half metallicity in Cr substituted FeTiSn.

Band structure tailoring has been a great avenue to achieve the half-metallic electronic ground state in materials. Applying this approach to the full Heusler alloy FeTiSn, Cr is introduced systematically at Ti site that conforms to the chemical formula [Formula: see text]Sn. Compositions so obtained have been investigated for its electronic, magnetic, and electrical transport properties with an aim to observe the half-metallic ferromagnetic ground state, anticipated theoretically for FeCrSn.

Elucidating the Mechanism of Li Insertion into FeS/Carbon Synchrotron Studies.

The detailed understanding of kinetic and phase dynamics taking place in lithium-ion batteries (LIBs) is crucial for optimizing their properties. It was previously reported that FeS/C nanocomposites display a superior performance as anode materials in LIBs. However, the underlying lithium storage mechanism was not entirely understood during the 1st cycle.

Investigation of the role and chemical form of iron in the ovarian carcinogenesis process.

Background: Ovarian cancer is one of the most frequent types of gynaecological malignancy among women. Despite the advances in diagnostic techniques, ovarian tumours are still detected at a late stage, thus the survival rate is very low. Iron is an essential metal in the human body, yet its potential role in ovarian carcinogenesis is yet to be determined.

Mechanism Study of Carbon Coating Effects on Conversion-Type Anode Materials in Lithium-Ion Batteries: Case Study of ZnMnO and ZnO-MnO Composites.

The carbon coating strategy is intensively used in the modification of conversion-type anode materials to improve their cycling stability and rate capability. Thus, it is necessary to elucidate the modification mechanism induced by carbon coating. For this purpose, bare ZnMnO, carbon-derivative-coated ZnMnO, and carbon-coated ZnO-MnO composite materials have been synthesized and investigated in-depth.

An evidence of local structural disorder across spin-reorientation transition in DyFeO: an extended x-ray absorption fine structure (EXAFS) study.

The present work is aimed at exploring the local atomic structure modifications related to the spin reorientation transition (SRT) in DyFeO orthoferrite exploiting x-ray absorption fine structure (XAFS) spectroscopy. For this purpose we studied by XAFS the evolution of the local atomic structure around Fe and Dy as function of temperature (10-300 K) in a DyFeO sample having the SRT around 50-100 K. For sake of comparison we studied a YFeO sample having no SRT.

In Operando Synchrotron Diffraction and in Operando X-ray Absorption Spectroscopy Investigations of Orthorhombic VO Nanowires as Cathode Materials for Mg-Ion Batteries.

Orthorhombic VO nanowires were successfully synthesized via a hydrothermal method. A cell-configuration system was built utilizing VO as the cathode and 1 M Mg(ClO) electrolyte within acetonitrile, together with Mg MoS ( x ≈ 2) as the anode to investigate the structural evolution and oxidation state and local structural changes of VO. The VO nanowires deliver an initial discharge/charge capacity of 103 mAh g/110 mAh g and the highest discharge capacity of 130 mAh g in the sixth cycle at C/20 rate in the cell-configuration system.