Updated diagnostic criteria and nomenclature for neurofibromatosis type 2 and schwannomatosis: An international consensus recommendation.

PURPOSE: Neurofibromatosis type 2 (NF2) and schwannomatosis (SWN) are genetically distinct tumor predisposition syndromes with overlapping phenotypes. We sought to update the diagnostic criteria for NF2 and SWN by incorporating recent advances in genetics, ophthalmology, neuropathology, and neuroimaging. METHODS: We used a multistep process, beginning with a Delphi method involving global disease experts and subsequently involving non-neurofibromatosis clinical experts, patients, and foundations/patient advocacy groups. RESULTS: We reached consensus on the minimal clinical and genetic criteria for diagnosing NF2 and SWN. These criteria incorporate mosaic forms of these conditions. In addition, we recommend updated nomenclature for these disorders to emphasize their phenotypic overlap and to minimize misdiagnosis with neurofibromatosis type 1. CONCLUSION: The updated criteria for NF2 and SWN incorporate clinical features and genetic testing, with a focus on using molecular data to differentiate the 2 conditions. It is likely that continued refinement of these new criteria will be necessary as investigators study the diagnostic properties of the revised criteria and identify new genes associated with SWN. In the revised nomenclature, the term "neurofibromatosis 2" has been retired to improve diagnostic specificity.

miR-497 and 219 in blood aid meningioma classification.

INTRODUCTION: The current WHO classification and methylation status help predict meningioma recurrence and prognosis. However, up to date, there is no circulating biomarker showing clinical value in meningioma diagnosis or classification. Circulating miRNAs showed the potential to be used as cancer biomarkers in various tumours. This research evaluated specific miRNAs, miR-497 and miR-219, as convenient and efficient predictors of meningioma grades. METHODS: We studied serum and exosomal levels of miR-497 in 74 meningioma samples (WHO grade I = 25, WHO grade II = 25, and WHO grade III = 24) and 53 healthy controls. The serum level of miR-219 was studied in 56 meningioma samples WHO grade I = 22, WHO grade II = 14, and WHO grade III = 20). We used qPCR for miRNA quantification. We also tested two different normalisers, endogenous and external, and evaluated their impact on the diagnostic value of miR-497. RESULTS: The serum and exosomal levels of miR-497 distinguished meningioma from the control samples. Moreover, miR-497 was a suitable identifier for meningioma grade. When we combined miR-497 and miR-219, the efficacy of the combined biomarker was higher than miR-497 or miR-219 when used individually in meningioma classification. Both miR-497 and miR-219 showed a noticeable change with the methylation class of meningioma. CONCLUSION: This study shows that serum miR-497 is an effective and easy-to-measure biomarker for meningioma diagnosis and classification. Moreover, when we combined miR-497 and miR-219, the combined biomarker showed enhanced accuracy in meningioma classification. Furthermore, this is the first study to evaluate the correlation between serum circulating miRNA and the methylation status in meningioma.

Structural, Magnetic and Catalytic Properties of a New Vacancy Ordered Perovskite Type Barium Cobaltate BaCoO2.67.

A new vacancy ordered, anion deficient perovskite modification with composition of BaCoO2.67 (Ba3 Co3 O8 □1 ) has been prepared via a two-step heating process. Combined Rietveld analysis of neutron and X-ray powder diffraction data shows a novel ordering of oxygen vacancies not known before for barium cobaltates. A combination of neutron powder diffraction, magnetic measurements, and density functional theory (DFT) studies confirms G-type antiferromagnetic ordering. From impedance measurements, the electronic conductivity of the order of 10-4  S cm-1 is determined. Remarkably, the bifunctional catalytic activity for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is found to be comparable to that of Ba0.5 Sr0.5 Co0.8 Fe0.2 O3-y , confirming that charge-ordered anion deficient non-cubic perovskites can be highly efficient catalysts.

Structural and Magnetic Properties of BaFeO2.667 Synthesized by Oxidizing BaFeO2.5 Obtained via Nebulized Spray Pyrolysis.

A vacancy-ordered perovskite-type compound Ba3Fe3O8 (BaFeO2.667) was prepared by oxidizing BaFeO2.5 (P21/c) with the latter compound obtained by a spray pyrolysis technique. The structure of Ba3Fe3O8 was found to be isotypic to Ba3Fe3O7F (P21/m) and can be written as Ba3Fe3+2Fe4+1O8. Mössbauer spectroscopy and ab initio calculations were used to confirm mixed iron oxidation states, showing allocation of the tetravalent iron species on the tetrahedral site, and octahedral as well as square pyramidal coordination for the trivalent species within a G-type antiferromagnetic ordering. The uptake and release of oxygen were investigated over a broad temperature range from room temperature to 1100 °C under pure oxygen and ambient atmosphere via a combination of DTA/TG and variable temperature diffraction measurements. The compound exhibited a strong lattice enthalpy driven reduction to monoclinic and cubic BaFeO2.5 at elevated temperatures.

Investigation of the thermal removal steps of capping agents in the synthesis of bimetallic iridium-based catalysts for the ethanol oxidation reaction.

Two iridium-based catalysts (namely IrSn and IrNi) are synthesised via a polyol route involving capping agents. The capping agents are removed according to a time-consuming multistep heat-treatment protocol described in the literature (N2 → N2/O2 → H2). In this work the effect of each of these steps on the structural composition and catalytic activity is investigated by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and electrochemistry. It is shown that heating in nitrogen is not required, whereas air is the most effective for the removal of the capping agents. Besides FT-IR, the analysis of sp3 carbon (from XPS) turned out to give reasonable insights into capping agent removal. Induced by hydrogen treatment no further change of the surface occurs, while particles tend to grow and become more crystalline. While structural changes are similar for both catalysts, the impact of each of the steps on the catalysis is different: the activity per gram of iridium becomes even lower for IrSn (an electrochemical cleaning agent that was used as reference measurements, seems best suited) while the activity is doubled for the IrNi case. Our results illustrate that the selection of the cleaning procedure strongly depends on the investigated system and should be optimised individually.

Topochemical Fluorination of n = 2 Ruddlesden-Popper Type Sr3Ti2O7 to Sr3Ti2O5F4 and Its Reductive Defluorination.

Within this study, we show that a sequence of substitutive topochemical fluorination of the n = 2 Ruddlesden-Popper type compounds Sr3Ti2O7 to Sr3Ti2O5F4 followed by reductive topochemical defluorination reactions between the oxyfluoride and the reducing agent sodium hydride allows for a substantial reduction of the oxidation state of Ti due to selective extraction and hydride substitution of fluoride ions. The oxyfluoride Sr3Ti2O5F4 has been synthesized and characterized structurally for the first time. The defluorination experiments have been conducted at temperatures as low as 300 °C, enabling also the reduction of this metastable compound. The evolution of phase fractions and unit cell volumes of various reduced phases as well as of side products has been monitored by an X-ray diffraction study as a function of the amount of sodium hydride used. Strong structural changes within the reduced phases, involving considerable decreases in the c lattice parameters partly accompanied by symmetry, lowering have been observed. To gain a deeper understanding of the structural changes, selected reduction reaction products have been further investigated by coupled analysis of X-ray and neutron powder diffraction data. Moreover, changes in the oxidation state of Ti have been studied using magnetic measurements and X-ray photoelectron spectroscopy examining differences between the bulk and the surface properties. Additionally, similarities and differences between previously published results on the topochemical defluorination of the n = 1 Ruddlesden-Popper type compound Sr2TiO3F2 are discussed.

Exploring Active Sites in Multi-Heteroatom-Doped Co-Based Catalysts for Hydrogen Evolution Reactions.

Today, metal-N- as well as metal-S-doped carbon materials are known to catalyze the hydrogen evolution reaction (HER). However, especially N- and S-co-doped catalysts reach highest activity, but it remains unclear if the activity is related to MNx or MSy (M=metal) sites. In this work we apply a simple method for multi-heteroatom doping and investigate the effect of cobalt content on the HER in acidic medium. The CoNx and CoSy sites were evidenced on the basis of structural characterization by Raman, X-ray induced photoelectron spectroscopy, and TEM. The presence of sulfur enables the formation of a larger number of CoNx sites. Structure-performance relationship proves that the HER activity is dominated by CoNx rather than CoSy sites. The most active catalysts also exhibit an excellent stability under galvanostatic conditions making them of interest for electrolyser application.

Topochemical Fluorination of La2NiO4+d: Unprecedented Ordering of Oxide and Fluoride Ions in La2NiO3F2.

The Ruddlesden-Popper (K2NiF4) type phase La2NiO3F2 was prepared via a polymer-based fluorination of La2NiO4+ d. The compound was found to crystallize in the orthorhombic space group Cccm ( a = 12.8350(4) Å, b = 5.7935(2) Å, c = 5.4864(2) Å). This structural distortion results from an ordered half occupation of the interstitial anion layers and has not been observed previously for K2NiF4-type oxyfluoride compounds. From a combination of neutron and X-ray powder diffraction and 19F magic-angle spinning NMR spectroscopy, it was found that the fluoride ions are only located on the apical anion sites, whereas the oxide ions are located on the interstitial sites. This ordering results in a weakening of the magnetic Ni-F-F-Ni superexchange interactions between the perovskite layers and a reduction of the antiferromagnetic ordering temperature to 49 K. Below 30 K, a small ferromagnetic component was found, which may be the result of a magnetic canting within the antiferromagnetic arrangement and will be the subject of a future low-temperature neutron diffraction study. Additionally, density functional theory-based calculations were performed to further investigate different anion ordering scenarios.

Vanadium Oxyfluoride/Few-Layer Graphene Composite as a High-Performance Cathode Material for Lithium Batteries.

Metal oxyfluoride compounds are gathering significant interest as cathode materials for lithium ion batteries at the moment because of their high theoretical capacity and resulting high energy density. In this regard, a new and direct approach is presented to synthesize phase-pure vanadium oxyfluoride (VO2F). The structure of VO2F was identified by Rietveld refinement of the powder X-ray diffraction (XRD) pattern. It crystallizes in a perovskite-type structure with disorder of the oxide and fluoride ions. The as-synthesized VO2F was tested as a cathode material for lithium ion batteries after being surface-coated with few-layer graphene. The VO2F delivered a first discharge capacity of 254 mA h g(-1) and a reversible capacity of 208 mA h g(-1) at a rate of C/20 for the first 20 cycles with an average discharge voltage of 2.84 V, yielding an energy density of 591 W h kg(-1). Improved rate capability that outperforms the previous report has been achieved, showing a discharge capacity of 150 mA h g(-1) for 1 C. The structural changes during lithium insertion and extraction were monitored by ex-situ XRD analysis of the electrodes discharged and charged to various stages. Lithium insertion results in an irreversible structural change of the anion lattice from (3)/4 cubic close packing to hexagonal close packing to accommodate the inserted lithium ions while keeping the overall space-group symmetry. For the first time we have revealed a structural change for the ReO3-type structure of as-prepared VO2F to the RhF3 structure after lithiation/delithiation, with structural changes that have not been observed in previous reports. Furthermore, the new synthetic approach described here would be a platform for the synthesis of new oxyfluoride compounds.

VOCl as a Cathode for Rechargeable Chloride Ion Batteries.

A novel room temperature rechargeable battery with VOCl cathode, lithium anode, and chloride ion transporting liquid electrolyte is described. The cell is based on the reversible transfer of chloride ions between the two electrodes. The VOCl cathode delivered an initial discharge capacity of 189 mAh g(-1) . A reversible capacity of 113 mAh g(-1) was retained even after 100 cycles when cycled at a high current density of 522 mA g(-1) . Such high cycling stability was achieved in chloride ion batteries for the first time, demonstrating the practicality of the system beyond a proof of concept model. The electrochemical reaction mechanism of the VOCl electrode in the chloride ion cell was investigated in detail by ex situ X-ray diffraction (XRD), infrared spectroscopy (FTIR), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The results confirm reversible deintercalation-intercalation of chloride ions in the VOCl electrode.

Introducing a large polar tetragonal distortion into Ba-doped BiFeO3 by low-temperature fluorination.

This article reports on the synthesis and crystallographic and magnetic structure of barium-doped BiFeO3 compounds with approximate composition Bi(1-x)Ba(x)FeO(3-x/2), as well as those of the fluorinated compounds Bi(1-x)Ba(x)FeO(3-x)F(x) (both with x = 0.2, 0.3), prepared by low-temperature fluorination of the oxide precursors using polyvinylidenedifluoride. Whereas the oxide compounds were obtained as cubic (x = 0.2) and slightly tetragonal (x = 0.3, c/a ≈ 1.003) distorted perovskite compounds, a large tetragonal polar distortion was observed for the oxyfluoride compounds (c/a ≈ 1.08 for x = 0.2 and ∼1.05 for x = 0.3), being isostructural to tetragonal PbTiO3. Although described differently in previous reports on Ba-doped BiFeO3, the observed remanent magnetization is found to agree well with the amount of BaFe12O19 only detectable by neutron diffraction and the well-known magnetic properties of BaFe12O19. The oxyfluoride compounds show G-type antiferromagnetic ordering with magnetic moments lying in the a/b plane.

Crystallographic and magnetic structure of the perovskite-type compound BaFeO2.5: unrivaled complexity in oxygen vacancy ordering.

We report here on the characterization of the vacancy-ordered perovskite-type structure of BaFeO2.5 by means of combined Rietveld analysis of powder X-ray and neutron diffraction data. The compound crystallizes in the monoclinic space group P2(1)/c [a = 6.9753(1) Å, b = 11.7281(2) Å, c = 23.4507(4) Å, ß = 98.813(1)°, and Z = 28] containing seven crystallographically different iron atoms. The coordination scheme is determined to be Ba7(FeO4/2)1(FeO3/2O1/1)3(FeO5/2)2(FeO6/2)1 = Ba7Fe([6])1Fe([5])2Fe([4])4O17.5 and is in agreement with the (57)Fe Mössbauer spectra and density functional theory based calculations. To our knowledge, the structure of BaFeO2.5 is the most complicated perovskite-type superstructure reported so far (largest primitive cell, number of ABX2.5 units per unit cell, and number of different crystallographic sites). The magnetic structure was determined from the powder neutron diffraction data and can be understood in terms of "G-type" antiferromagnetic ordering between connected iron-containing polyhedra, in agreement with field-sweep and zero-field-cooled/field-cooled measurements.

Reconsidering Anode Materials for Fluoride-Ion Batteries-The Unexpected Roles of Carbide Formation.

Carbon is a ubiquitous additive to enhance the electrical conductivity of battery electrodes. Although carbon is generally assumed to be inert, the poor reversibility seen in some fluoride-ion battery electrodes has not been explained or systematically explored. Here, we utilize the Materials Project database to assess electrode deactivation reactions that result in the formation of a metal carbide. Specifically, we compare the theoretical potentials of MFy reduction to either the corresponding metal M or metal carbide MCx . We find that the formation of MCx is unlikely to be important in anodes that operate at modest reduction potentials, such as those made from electronegative metals like Zn, Sn, or Pb. However, in anodes that operate at extreme reduction potentials, such as alkaline earths or lanthanides, we find that formation of MCx is relevant and can emerge as a mechanism for capacity loss. Thus, side reactions of metals with carbon additives that form metal carbides possibly explain the poor reversibility of lanthanide or alkaline earth metal-based electrode materials. Finally, we highlight that the carbide formation process might be exploited for designing cheap anode systems with improved reversibility.

Recycling of All-Solid-State Li-ion Batteries: A Case Study of the Separation of Individual Components Within a System Composed of LTO, LLZTO and NMC.

With the current global projection of over 130 million electric vehicles (EVs), there soon will be a need for battery waste management. Especially for all-solid-state lithium-ion batteries (lithium ASSBs), aspects of waste management and circular economy have not been addressed so far. Within such ASSBs, the use of solid-electrolytes like garnet-type Li6.5 La3 Zr1.5 Ta0.5 O12 (LLZTO) may shift focus on strategies to recover not only the transition metal elements but also elements like La/Zr/Ta. In this work, we present a two-step recycling approach using citric acid as the leaching agent to separate and recover the individual components of a model cell comprising of Li4 Ti5 O12 (LTO) anode, Li6.5 La3 Zr1.5 Ta0.5 O12 (LLZTO) garnet electrolyte and LiNi1/3 Mn1/3 Co1/3 O2 (NMC) cathode. We observe that by adjusting the concentration of citric acid, it was possible to separate the materials from each other without strong mixing of individual phases and also to maintain their principle performance characteristics. Thus, the process developed has a potential for upscaling and can guide towards considering separation capability of battery components in the development of lithium ASSBs.

Pressure-Induced Structural Behavior of Orthorhombic Mn3(VO4)2: Raman Spectroscopic and X-ray Diffraction Investigations.

The effect of high pressure on the structure of orthorhombic Mn3(VO4)2 is investigated using in situ Raman spectroscopy and X-ray powder diffraction up to high pressures of 26.2 and 23.4 GPa, respectively. The study demonstrates a pressure-induced structural phase transition starting at 10 GPa, with the coexistence of phases in the range of 10-20 GPa. The sluggish first-order phase transition is complete by 20 GPa. Importantly, the new phase could be recovered at ambient conditions. Raman spectra of the recovered new phase indicate increased distortion and as a consequence the lowering of the local symmetry of the VO4 tetrahedra. This behavior is different from that reported for isostructural compounds Zn3(VO4)2 and Ni3(VO4)2 where both show stable structures, although almost similar anisotropic compression of the unit cell is observed. The transition observed in orthorhombic Mn3(VO4)2 could be due to the internal charge transfer between the cations, which favors the structural transition at lower pressures and the eventual recovery of the new phase even upon pressure release in comparison to other isostructural compounds. The experimental equation of state parameters obtained for orthorhombic Mn3(VO4)2 match excellently with empirically calculated values reported earlier.

Towards Recycling of LLZO Solid Electrolyte Exemplarily Performed on LFP/LLZO/LTO Cells.

All-solid-state lithium ion batteries (ASS-LIBs) are promising due to their safety and higher energy density as compared to that of conventional LIBs. Over the next few decades, tremendous amounts of spent ASS-LIBs will reach the end of their cycle life and would require recycling in order to address the waste management issue along with reduced exploitation of rare elements. So far, only very limited studies have been conducted on recycling of ASS-LIBS. Herein, we investigate the recycling of the Li7 La3 Zr2 O12 (LLZO) solid-state electrolyte in a LiFePO4 /LLZO/Li4 Ti5 O12 system using a hydrometallurgical approach. Our results show that different concentration of the leaching solutions can significantly influence the final product of the recycling process. However, it was possible to recover relatively pure La2 O3 and ZrO2 to re-synthesize the cubic LLZO phase, whose high purity was confirmed by XRD measurements.

On the Surface Modification of LLZTO with LiF via a Gas-Phase Approach and the Characterization of the Interfaces of LiF with LLZTO as Well as PEO+LiTFSI.

In this study we present gas-phase fluorination as a method to create a thin LiF layer on Li6.5La3Zr1.5Ta0.5O12 (LLZTO). We compared these fluorinated films with LiF films produced by RF-magnetron sputtering, where we investigated the interface between the LLZTO and the deposited LiF showing no formation of a reaction layer. Furthermore, we investigated the ability of this LiF layer as a protection layer against Li2CO3 formation in ambient air. By this, we show that Li2CO3 formation is absent at the LLZTO surface after 24 h in ambient air, supporting the protective character of the formed LiF films, and hence potentially enhancing the handling of LLZTO in air for battery production. With respect to the use within hybrid electrolytes consisting of LLZTO and a mixture of polyethylene oxide (PEO) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), we also investigated the interface between the formed LiF films and a mixture of PEO+LiTFSI by X-ray photoelectron spectroscopy (XPS), showing decomposition of the LiTFSI at the interface.

One-Step Thermal Gradient- and Antisolvent-Free Crystallization of All-Inorganic Perovskites for Highly Efficient and Thermally Stable Solar Cells.

All-inorganic perovskites have emerged as promising photovoltaic materials due to their superior thermal stability compared to their heat-sensitive hybrid organic-inorganic counterparts. In particular, CsPbI2 Br shows the highest potential for developing thermally-stable perovskite solar cells (PSCs) among all-inorganic compositions. However, controlling the crystallinity and morphology of all-inorganic compositions is a significant challenge. Here, a simple, thermal gradient- and antisolvent-free method is reported to control the crystallization of CsPbI2 Br films. Optical in situ characterization is used to investigate the dynamic film formation during spin-coating and annealing to understand and optimize the evolving film properties. This leads to high-quality perovskite films with micrometer-scale grain sizes with a noteworthy performance of 17% (≈16% stabilized), fill factor (FF) of 80.5%, and open-circuit voltage (VOC ) of 1.27 V. Moreover, excellent phase and thermal stability are demonstrated even after extreme thermal stressing at 300 °C.

Compositional Dependence of Li-Ion Conductivity in Garnet-Rich Composite Electrolytes for All-Solid-State Lithium-Ion Batteries-Toward Understanding the Drawbacks of Ceramic-Rich Composites.

Composite electrolytes comprising a polymer plus Li salt matrix and embedded fillers have the potential of realizing high lithium-ion conductivity, good mechanical properties, wide electrochemical operational window, and stability against metallic lithium, all of which are essential for the development of high-energy-density all-solid-state lithium-ion batteries. In this study, a solvent-free approach has been used to prepare composite electrolytes with tetragonal and cubic phase garnets synthesized via nebulized spray pyrolysis with polyethylene oxide (PEO) being the polymer component. Electrochemical impedance spectroscopy (EIS) is used to examine a series of composites with different garnets and weight fractions. The results show that with the increase in the ceramic weight fraction in the composites, ionic conductivity is reduced and alternative Li-ion transport pathways become accessible for composites as compared to the filler-free electrolytes. An attempt is made to understand the ion transport mechanism within the composites. The role of the chemical and morphological properties of the ceramic filler in polymer-rich and ceramic-rich composite electrolytes is explained by studying the blends of nonconducting ceramics with the Li-conducting polymer, indicating that the intrinsic conductivity of the ceramic filler significantly contributes to the overall conductive process in the ceramic-rich systems. Further, the stability of the garnet/PEO interface is studied via X-ray photoelectron spectroscopy, and its impact on the lithium-ion transport is studied using EIS.

Insights into the Rich Polymorphism of the Na+ Ion Conductor Na3PS4 from the Perspective of Variable-Temperature Diffraction and Spectroscopy.

Solid electrolytes are crucial for next-generation solid-state batteries, and Na3PS4 is one of the most promising Na+ conductors for such applications, despite outstanding questions regarding its structural polymorphs. In this contribution, we present a detailed investigation of the evolution in structure and dynamics of Na3PS4 over a wide temperature range 30 < T < 600 °C through combined experimental-computational analysis. Although Bragg diffraction experiments indicate a second-order phase transition from the tetragonal ground state (α, P4̅21 c) to the cubic polymorph (ß, I4̅3m) above ∼250 °C, pair distribution function analysis in real space and Raman spectroscopy indicate remnants of a tetragonal character in the range 250 < T < 500 °C, which we attribute to dynamic local tetragonal distortions. The first-order phase transition to the mesophasic high-temperature polymorph (γ, Fddd) is associated with a sharp volume increase and the onset of liquid-like dynamics for sodium-cations (translational) and thiophosphate-polyanions (rotational) evident by inelastic neutron and Raman spectroscopies, as well as pair-distribution function and molecular dynamics analyses. These results shed light on the rich polymorphism of Na3PS4 and are relevant for a range host of high-performance materials deriving from the Na3PS4 structural archetype.