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BaO-CaO-Al 2 O 3 aluminate impregnants, the source for producing Ba for Ba-W cathodes, play an indispensable role in the cathode performance. Possessing the high thermionic emission property and low melting point is a huge challenge for the aluminate impregnants of Ba-W cathodes. Here, a "kill two birds with one stone" strategy is designed to simultaneously reduce the melting points and increase the thermionic emission capability. A novel BaO-CaO-Al 2 O 3 -BaF 2 quaternary aluminate impregnant was obtained and the addition of BaF 2 decreases the viscosity and melting point of the aluminate impregnants. When the content of BaF 2 reaches 0.15 mol, the emission current density of Ba-W cathode impregnated with quaternary aluminate impregnant can reach 15.89 A cm−2 at 1100°C b , which is 1.11 times higher than that of the without BaF 2. In contrast, the continuous rise of BaF 2 leads to the decreased emission current density due to the formation of a glassy phase. It is found that the introduction of BaF 2 led to the formation of a new skeletal structure in the quaternary aluminate impregnant – [AlO 3 F], which coexists with [AlO n ] (n = 4, 5, 6) to reduce the melting point. Theoretical calculations confirm that introducing fluorine triggers the number of point defects and barium compound in impregnant to gain electron convert to the metastable Baδ+ (0 < δ < 2), enhancing the ability to produce active substance Ba. This work provides new inspiration for developing novel impregnants for Ba-W cathodes. [ABSTRACT FROM AUTHOR]

The reaction of hydrazinium sulfate and chlorosulfonic acid in pyridine leads to the pyridinium salt of the hydrazine disulfonate anion, [(SO3)HNNH(SO3)]2−. The salt is the starting material for the preparation of further hydrazine disulfonates, for example of alkaline metals and barium. In all compounds, the [(SO3)HNNH(SO3)]2− anion adopts the gauche conformation. The conformer is chiral but all of the investigated compounds crystallize as racemates. The disulfonate anion can occur in another constitution with the two sulfonate groups attached to only one nitrogen atom. This so‐called hydrazine iso‐disulfonate, [H2NN(SO3)2]2−, has been prepared through a substitution reaction between potassium imidodisulfonate, K2[HN(SO3)2], and hydroxylamine‐O‐sulfonic acid, H2NOSO3H. The hydrazine iso‐disulfonate anion has been crystallized as potassium and barium compound, respectively. The compounds were characterized by XRD, vibrational spectroscopy, DFT calculations and thermal analyses. [ABSTRACT FROM AUTHOR]

The reaction of hydrazinium sulfate and chlorosulfonic acid in pyridine leads to the pyridinium salt of the hydrazine disulfonate anion, [(SO3)HNNH(SO3)]2−. The salt is the starting material for the preparation of further hydrazine disulfonates, for example of alkaline metals and barium. In all compounds, the [(SO3)HNNH(SO3)]2− anion adopts the gauche conformation. The conformer is chiral but all of the investigated compounds crystallize as racemates. The disulfonate anion can occur in another constitution with the two sulfonate groups attached to only one nitrogen atom. This so‐called hydrazine iso‐disulfonate, [H2NN(SO3)2]2−, has been prepared through a substitution reaction between potassium imidodisulfonate, K2[HN(SO3)2], and hydroxylamine‐O‐sulfonic acid, H2NOSO3H. The hydrazine iso‐disulfonate anion has been crystallized as potassium and barium compound, respectively. The compounds were characterized by XRD, vibrational spectroscopy, DFT calculations and thermal analyses. [ABSTRACT FROM AUTHOR]

Amidst the swift expansion of the electric vehicle industry, the imperative for alternative battery technologies that balance economic feasibility with sustainability has reached unprecedented importance. Herein, we utilized Perovskite-based oxide compounds barium titanate (BaTiO3) and strontium titanate (SrTiO3) nanoparticles as anode materials for lithium-ion batteries from straightforward and standard carbonate-based electrolyte with 10% fluoroethylene carbonate (FEC) additive [1M LiPF6 (1:1 EC: DEC) + 10% FEC]. SrTiO3 and BaTiO3 electrodes can deliver a high specific capacity of 80 mA h g−1 at a safe and low average working potential of ≈0.6 V vs. Li/Li+ with excellent high-rate performance with specific capacity of ~90 mA h g−1 at low current density of 20 mA g−1 and specific capacity of ~80 mA h g−1 for over 500 cycles at high current density of 100 mA g−1. Our findings pave the way for the direct utilization of perovskite-type materials as anode materials in Li-ion batteries due to their promising potential for Li+ ion storage. This investigation addresses the escalating market demands in a sustainable manner and opens avenues for the investigation of diverse perovskite oxides as advanced anodes for next-generation metal-ion batteries. [ABSTRACT FROM AUTHOR]

Purpose: Few studies have assessed trochanteric vascularity despite its implications for bone healing and surgical approaches. This study aimed to assess the regional arterial contributions of the medial femoral circumflex artery (MFCA) versus the lateral femoral circumflex artery (LFCA) to trochanteric vascularity. Methods: Ten adult human cadaveric pelvises to mid‐femur specimens were obtained. One hip was randomly assigned experimental (either MFCA or LFCA MRI‐contrast infusion) and contralateral as control (MFCA and LFCA magnetic resonance imaging [MRI]‐contrast infusion). Vascular dissection was performed for MFCA and LFCA cannulation. Pre‐ and post‐contrast 3T MRI was completed, and intra‐osseous contributions were quantified by region: greater trochanter (GT), intertrochanteric (IT), lesser trochanter (LT) and subtrochanteric (ST). A polyurethane compound mixed with barium sulfate was injected into the LFCA cannula, and into the MFCA cannula for the contralateral hip. Computed tomography (CT) imaging was completed to assess terminal branch locations. Results: MFCA provided the majority of arterial contributions to the full trochanteric region (68.5% MFCA, 31.5% LFCA; standard deviation [SD]: 10.7%, p < 0.001). Over 70% of arterial contributions to ST, LT and IT regions are derived from MFCA. GT contributions were more balanced (52.5% MFCA, 47.5% LFCA; SD: 33.7%; p = 0.853). Significant differences were found between MFCA and LFCA contributions in all regions except for the GT. CT revealed multiple consistent MFCA and LFCA trochanteric terminal branches. Conclusions: MFCA provided the dominant trochanteric arterial supply, which highlights MFCA's importance to overall hip vascularity. LFCA's trochanteric contribution was smaller but still provided trochanteric contributions, especially the GT region. Knowledge of trochanteric arterial contributions can be beneficial for optimizing surgical approaches and fixation to protect terminal branches during trochanteric fracture, nonunion treatment and trochanteric osteotomies. Level of Evidence: Not applicable. [ABSTRACT FROM AUTHOR]

The article presents an interprofessional education activity between dietetics and radiography students which enhances skills and knowledge through an evidence-based framework that incorporates learner self-assessment, facilities focused discussion and provides directive feedback and teaching.

[BaTiO_{3}]_{m}/[BaZrO_{3}]_{n} (m, n=4-12) superlattices are used to demonstrate the fabrication and deterministic control of an artificial relaxor. X-ray diffraction and atomic-resolution imaging studies confirm the production of high-quality heterostructures. With decreasing BaTiO_{3} layer thickness, dielectric measurements reveal systematically lower dielectric-maximum temperatures, while hysteresis loops and third-harmonic nonlinearity studies suggest a transition from ferroelectriclike to relaxorlike behavior driven by tuning the random-field strength. This system provides a novel platform for studying the size effect and interaction length scale of the nanoscale-polar structures in relaxors.

Abstract Continuous three‐dimensional BaTiO3 (3DBT) ceramic network was prepared by the sol‐gel method using cleanroom wipers as the template. Subsequently, flexible 3DBT/polyvinyl alcohol‐boron nitride nanosheets (PVA‐BNNS) composite dielectric films were facilely fabricated by inversely introducing different BNNS concentrations of PVA‐BNNS solution into the 3DBT network. The results demonstrated that PVA solution effectively embedded into the 3DBT framework through an inverse infiltration process, thereby endowing the material with excellent flexibility. The content of 3DBT in the saturated 3DBT/PVA‐BNNS composite was ∼27 wt% (6.9 vol%). In addition, the 3DBT/PVA‐1.0%BNNS system exhibited an excellent dielectric constant of 17.4 (at 1 kHz), a high breakdown strength of 114.5 kV·mm−1 and an energy density of 2.51 J·cm−3 (at 110 kV·mm−1), being 1.67, 1.58 and 7.17 times higher than those of traditional fabricated 27 wt% nano‐BT/PVA (at 70 kV·mm−1) composite, respectively. What's more, the obtained 3DBT/PVA‐BNNS dielectric film exhibited superior thermal and mechanical stability, indicating potential applications in harsh environments.

In the crystals of alkaline earth metal compounds strontium and barium with the non-steroidal anti-inflammatory drug nimesulide, the strontium cation is nine-coordinated with a distorted tricapped trigonal prismatic geometry TCTPR-9, whereas the ten-coordinated barium ion exhibits a distorted tetracapped trigonal prismatic geometry TCTPR-10. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to test the feasibility for quantifying changes in oropharyngeal swallowing impairment in response to alteration in bolus viscosity using a reliable and valid method of observational measurement--the Modified Barium Swallow Impairment Profile (MBSImP). Method: This retrospective analysis included a heterogeneous cohort of 119 patients with suspected dysphagia that underwent a videofluoroscopic swallowing study as part of clinical care. Using consensus scoring, two expert clinicians assigned MBSImP scores to components related to oropharyngeal swallowing function between two bolus viscosities (thin liquid and pudding): epiglottic movement, laryngeal elevation, anterior hyoid excursion, tongue base retraction, pharyngeal stripping wave, and pharyngoesophageal segment opening (PESO). Comparisons between the two bolus viscosities were investigated for each component. Results: Higher (worse) scores were observed in the thin-liquid trial compared with the pudding trial for the following MBSImP components: anterior hyoid excursion (p = .03), epiglottic movement (p < .001), pharyngeal stripping wave (p < .001), and PESO (p = .002). Lower (better) scores were observed in the liquid trial compared with the pudding trial for one component--tongue base retraction (Component 15) only (p < .001). Conclusion: These findings provide further evidence for positive influences of viscosity on the swallow mechanism, including influences of sensory feedback on the sensorimotor swallow program. [ABSTRACT FROM AUTHOR]

Waste solutions from the electrolytic production of copper contain significant amounts of copper and nickel sulfates, sulfuric acid, arsenic and other components of the copper electrolyte. The processing of such solutions is considered in this work not only from the point of view of environmental protection, but also in terms of extracting various valuable components from the electrolyte into commercial products. A thermodynamic analysis of the interactions between barium and arsenic, as well as their compounds in the Ba(AsO2)2-Ba3(AsO4)2-H2O system was carried out based on the E-pH diagram. The possibility of using barium compounds as a precipitant for arsenic from copper electrorefining solutions has been demonstrated. The efficiency of removing arsenic (more than 84%) from the electrolyte using barium oxide in the form of sparingly soluble barium arsenate has been established. By adding calculated amounts of zinc oxide into the working solution, it is possible to form solutions containing certain concentrations of Cu, Ni, and Zn. By further adding zinc oxide into the solution, its deep dehydration was achieved. The resulting copper-nickel-zinc and nickel-zinc solutions are the raw material for producing non-ferrous metal alloys using the electromembrane method. [ABSTRACT FROM AUTHOR]

Objectives: This manuscript aims to present a novel and successful intervention for intractable aspiration following a supracricoid laryngectomy (SCL) that may avoid the need for total laryngectomy in patients experiencing intractable aspiration after SCL. Study design: This report describes a novel approach to treat intractable aspiration and feeding tube-dependency due to an incomplete posterior apposition of the laryngeal surface of the epiglottis to the arytenoids after a SCL in a 67-year-old man. Methods: The right and left aryepiglottic folds and the median glossoepiglottic fold were denuded using a CO2 laser. Then, an arytenoepiglottopexy was completed by placing 4-0 Vicryl between the lateral aspect of the epiglottis and arytenoids; thus, approximating these structures. Results: Two weeks after surgery, fiberoptic endoscopic evaluation of swallowing demonstrated improved closure of the larynx upon swallowing with great upgrading in the Penetration-Aspiration scale (PAS). PAS improved from a 6 to 2, corresponding to, transient penetration for moderately thick liquids and puree solids. He also demonstrated improved secretion management and airway protection. Following a 4-week course of intensive dysphagia therapy, a modified barium swallow revealed a significant improvement in airway protection, with a PAS score of 1 (no airway invasion). Conclusions: Chronic aspiration is a life-threatening condition that can severely reduce patients' quality of life. Despite the use of current therapeutic approaches, a subset of patients will remain plagued by persistent symptoms. We introduce an innovative, simple, and quick endoscopic technique that offers benefit in controlling aspiration after SCL. Level of Evidence: NA [ABSTRACT FROM AUTHOR]

M-type barium hexaferrites, BaFe(12−x)LaxO19 (x = 0.0, 0.05, 0.1, 0.15, and 0.2), were prepared by a low-cost solid-state reaction method. The specimens crystallized in a non-centrosymmetric hexagonal magnetoplumbite structure that belonged to the P63/mmc space group. Morphologically, the samples were dense with hexagonal plate-like grains and size variations of around 1.19–1.70 μm. The optical band gap of the system was reduced in the wide band-gap region from 1.78 to 1.74 eV. The band-gap values would be useful in photocatalysis and photovoltaics. The AC conductivity was enhanced with La3+ substitution, following Jonscher's power law. Maxwell–Wagner-type polarization was observed in the specimen, and tangent loss decreased with La3+ substitution. The values of the tangent loss were in the appropriate range for electromagnetic shielding applications. [ABSTRACT FROM AUTHOR]

Objective: To characterize the prevalence and presentation of laryngomalacia and efficacy of supraglottoplasty (SGP) in a cohort of patients with Pierre Robin Sequence (PRS). Design: Retrospective cohort study. Setting: Tertiary-care children's hospital. Patients, Participants: Consecutive patients with PRS born between January 2010 and June 2018. Main Outcome Measures: Chart review included demographics, comorbid airway obstruction including laryngomalacia, timing of surgical interventions, clinical symptoms, sleep study data, and modified barium swallow study data. Results : 126 patients with PRS were included; 54% had an associated syndrome, 64% had an overt cleft palate, and 22% had a submucous cleft palate. 64/126 were noted to have laryngomalacia (51%). Patients with concurrent PRS and laryngomalacia were significantly more likely to have submucous cleft palate (P =.005) and present with aspiration with cough (P =.01) compared to patients with PRS without laryngomalacia. Patients with concurrent laryngomalacia and PRS showed a significant decrease in apnea–hypopnea index (AHI) and obstructive AHI (OAHI) after mandibular distraction, with a median AHI and OAHI improvement of 22.3 (P =.001) and 19.8 (P =.002), respectively. Patients who underwent only SGP did not show significant improvement in these parameters (P =.112 for AHI, P =.064 for OAHI). Conclusions : The prevalence of laryngomalacia in our PRS cohort was 51%. Patients with PRS and laryngomalacia are more likely to present with overt aspiration compared to patients with PRS without laryngomalacia. These data support that laryngomalacia does not appear to be a contraindication to pursuing MDO. [ABSTRACT FROM AUTHOR]

Barium di-silicide (BaSi2) is a very promising absorber material for high-efficiency thin-film solar cells, due to its suitable bandgap, high light absorption coefficient, and long minority-carrier lifetime. In this study, we compare the nanostructure, layer composition, and point defects of BaSi2 thin films deposited by Radio Frequency (RF) sputtering, Thermal Evaporation (TE), and Molecular Beam Epitaxy (MBE), using Doppler Broadening Positron Annihilation Spectroscopy (DB-PAS) depth profiling, Raman spectroscopy, and x-ray diffraction. Our DB-PAS study on thermally annealed RF-sputter deposited and on TE-deposited BaSi2 layers, in a comparison with high quality BaSi2 films produced by MBE, points to the presence of vacancy-oxygen complexes and Si or Ba mono-vacancies, respectively, in the (poly)crystalline BaSi2 films. The degree of near-surface oxidation increases, going from MBE and TE to the industrially applicable RF-sputtered deposition synthesis. The use of a-Si capping layers on the thermally annealed RF-sputtered BaSi2 films leads to a clear reduction in sub-surface oxidation and improves the quality of the BaSi2 films, as judged from DB-PAS. [ABSTRACT FROM AUTHOR]

The barium aluminosilicate compound (BaAl 2 Si 2 O 8 or BAS) has been synthesized by powder reactive sintering within a Spark Plasma Sintering (SPS) device. The reaction paths between the precursors (alumina, silica and barium carbonate powders) have been deeply investigated at different temperatures from 900° to 1550°C in order to get at the end, the hexacelcian crystallographic form without any undesirable other compounds. Thanks to this approach, a 3 step thermal treatment is proposed to get a fully dense and nearly pure (98 wt%) BAS. [ABSTRACT FROM AUTHOR]

The equiatomic ternary BaTX (T=Pd, Pt, Au; X=Mg, Zn, Cd) phases were obtained by reaction of the elements in sealed tantalum ampoules. The compounds were characterized through their X‐ray powder patterns. BaAuMg and BaTCd (T=Pd, Pt, Au) crystallize with the TiNiSi type structure, while the compounds BaTZn (T=Pd, Pt) adopt the ZrBeSi type. The structures of BaAuMg and BaPdZn were refined from single crystal X‐ray diffractometer data: Pnma, a=801.34(5), b=467.71(8), c=924.07(10) pm, wR2=0.0955, 736 F2 values, 20 variables for BaAuMg and P63/mmc, a=449.68(2), c=901.62(4) pm, wR2=0.1172, 145 F2 values, 8 variables for BaPdZn. The structures derive from the aristotype AlB2. The gold and magnesium atoms form puckered Au3Mg3 hexagons with 284–328 pm Au−Mg while the Pd3Zn3 hexagons in BaPdZn are planar (260 pm Pd−Zn). Comparison of all known BaTX phases shows a range of the valence electron count (VEC) from 13 (BaMnGe) to 18 (BaAuP). The BaTX phases crystallize with seven different structure types and there is no obvious correlation with VEC. [ABSTRACT FROM AUTHOR]

Purpose: Swallow onset is commonly characterized by bolus location. Quantifying this swallow event using swallow reaction time (SRT) may further inform swallow assessment, but few studies have established normative reference values for SRT using a large sample size and well-tested, standardized, and validated videofluoroscopic swallow study (VFSS) approach. The purpose of this study was to investigate SRT in a large cohort of healthy adults and the effects of demographic (age, sex) and bolus (viscosity, volume) characteristics on SRT using the Modified Barium Swallow Impairment Profile approach. Method: Archival VFSSs of 195 healthy adults (21-89 years) were analyzed to obtain SRT across seven standardized swallow tasks ranging from thin to extremely thick liquid and a solid. Descriptive statistics were generated for age, sex, viscosity, and volume. Generalized estimating equation models were computed to explore the effects of demographic and bolus characteristics on SRT. Results: Variability in SRT was observed among healthy adults across all swallow tasks. Only viscosity significantly influenced SRT. Specifically, thicker viscosities resulted in longer SRT. Conclusions: Wide variability in SRT was observed in this large cohort of healthy adults across various liquid swallow tasks and a solid task. Thicker viscosities, in particular, yielded longer SRT and should be considered a normal variant. This study further provides normative SRT data related to a commonly used VFSS approach, which clinicians can use as reference values for their patient data. [ABSTRACT FROM AUTHOR]

Infiltration of an optimal amount of liquid (Ba3Cu5O8 denoted further as "035") for efficient peritectic growth is a primary requirement in the infiltration growth (IG) processing of high-quality REBa2Cu3O7-δ products. Recently, we optimized the Dy content and the time-temperature schedules for top-seeded IG processing of (Gd,Dy)Ba2Cu3O7–δ [(Gd,Dy)BCO] single grain superconductors. Aiming to fabricate larger sized (Gd,Dy)BCO (80 wt. % Gd2BaCuO5 and 20 wt. % of Dy2BaCuO5) single grain bulk superconductors, different liquid phase [LP = ErBa2Cu3O7–δ (Er-123) and mixed with 035] sources were employed and the LP content was optimized by varying its mass. The increase in Er-123+035 mass assured an abundant amount of liquids for peritectic reaction. The Er-123+035 ratio of 1:1.4 was found to be optimum. The optimized liquid phase infiltration enabled an effective control of (Gd,Dy)2BaCuO5 (211) secondary phase size and content in final microstructures. Bulk single-grain (Gd,Dy)BCO superconductors were fabricated by the top-seeded IG process with an LP mass of 1 and 1.4 wt. %. A fully grown single grain bulk (Gd,Dy)BCO superconductor was attained. The sufficient LP infiltration resulted in a greatly improved critical current and trapped field performance. Scaling of bulk volume flux pinning force was studied with the aim of identifying flux pinning mechanisms effectively occurring in the material. [ABSTRACT FROM AUTHOR]

A key assumption of optogenetics is that light only affects opsin-expressing neurons. However, illumination invariably heats tissue, and many physiological processes are temperature-sensitive. Commonly used illumination protocols increased the temperature by 0.2-2 °C and suppressed spiking in multiple brain regions. In the striatum, light delivery activated an inwardly rectifying potassium conductance and biased rotational behavior. Thus, careful consideration of light-delivery parameters is required, as even modest intracranial heating can confound interpretation of optogenetic experiments.

The stannide BaRhSn2 was synthesized by induction melting of an arc-melted RhSn2 precursor compound with barium in a sealed tantalum ampoule. The structure of BaRhSn2 was refined from single-crystal X-ray diffractometer data: MgCuAl2 type, Cmcm, a = 437.56(4), b = 1242.35(10), c = 767.30(6) pm, wR2 = 0.0845, 469 F2 values and 16 variables. The rhodium and tin atoms form a two-dimensional [RhSn2]δ− polyanionic network with short Rh–Sn (273–274 pm) and Sn–Sn (303–312 pm) distances. The large barium atoms lead to a substantial orthorhombic distortion of the (lonsdaleite-related) tin substructure, forcing a break of the Sn–Sn bond in b direction. This change in the tin substructure is reflected in the 119Sn Mössbauer spectrum. The tin atoms exhibit a higher s electron density which is expressed in an increased isomer shift of δ = 2.08(1) mm s−1 as compared to the previously reported stannide CaRhSn2 with a three-dimensional [RhSn2]δ− polyanionic network and δ = 1.96(4) mm s−1. [ABSTRACT FROM AUTHOR]

The stannide BaRhSn2 was synthesized by induction melting of an arc-melted RhSn2 precursor compound with barium in a sealed tantalum ampoule. The structure of BaRhSn2 was refined from single-crystal X-ray diffractometer data: MgCuAl2 type, Cmcm, a = 437.56(4), b = 1242.35(10), c = 767.30(6) pm, wR2 = 0.0845, 469 F2 values and 16 variables. The rhodium and tin atoms form a two-dimensional [RhSn2]δ− polyanionic network with short Rh–Sn (273–274 pm) and Sn–Sn (303–312 pm) distances. The large barium atoms lead to a substantial orthorhombic distortion of the (lonsdaleite-related) tin substructure, forcing a break of the Sn–Sn bond in b direction. This change in the tin substructure is reflected in the 119Sn Mössbauer spectrum. The tin atoms exhibit a higher s electron density which is expressed in an increased isomer shift of δ = 2.08(1) mm s−1 as compared to the previously reported stannide CaRhSn2 with a three-dimensional [RhSn2]δ− polyanionic network and δ = 1.96(4) mm s−1. [ABSTRACT FROM AUTHOR]

Dielectric and piezoelectric responses of slightly textured, lead barium niobate ceramics are studied. The designed morphotropic phase boundary composition ( Pb 0.63 Ba 0.37 Nb 2 O 6) shows considerable nonlinear dielectric and piezoelectric responses. While these nonlinear behaviors lead to significant instabilities of the functional properties, interesting features are revealed as a consequence of the texturing effect in the composition studied. An improved dielectric performance and a lower nonlinear piezoelectric response are observed when the electric field is applied to the sample in the forging direction. The results are quantitatively discussed in the framework of the Preisach and Rayleigh models. In this context, a decrease in the nonlinear response can be associated with a lower grain size related to the texture. The results of this work show that texturing is an effective route for controlling the undesirable nonlinear behavior of piezoceramics with tetragonal tungsten bronze structure. [ABSTRACT FROM AUTHOR]

This study aimed to produce a composite of barium sulphate and amorphous cellulose (Ba/AC) as a substrate for X-ray attenuation. Ba/AC was fabricated by converting the crystalline structure of eucalyptus pulp into an amorphous one. Subsequently, amorphous cellulose was regenerated using barium compounds (barium chloride and barium sulphate suspension) to obtain Ba/AC specimens (Ba/AC–BaCl2 and Ba/AC–BaSO4, respectively). All substrates were characterised by X-ray diffraction, scanning electron microscopy, and attenuated total reflectance-Fourier transform infrared spectroscopy. X-ray attenuation was studied by mixing 20% w/w Ba/AC and 80% w/w silicone rubber, coating the mixture on cotton fabrics, and comparing to barium sulphate powder (BaSO4), a conventional material. The coated fabrics were exposed to X-rays at tube voltages of 30 kV, 40 kV, and 60 kV. The fabrics coated with Ba/AC presented higher X-ray shielding efficiencies than those with BaSO4. Owing to the important role of amorphous cellulose in Ba/AC in distributing barium sulphate particles, more voids on the fabric surfaces were reduced than when using BaSO4. Moreover, the Ba/AC substrate preparation did not require a complex procedure and did not employ analytical-grade chemicals. Thus, a Ba/AC composite could be used as a substrate for X-ray shielding materials, owing to benefits of environmental-friendliness, nontoxicity, cost-effectiveness, and possibility of scaling up for commercial purposes. [ABSTRACT FROM AUTHOR]

Pulsed laser deposition films from Ba2FeMoO6 (BFMO) targets onto SrTiO3[001] (STO) substrates have been reported previously to have non-zero magnetism at 300 K, a majority of magnetic ordering at 240 K that is less than the 370 K ordering temperature of polycrystalline BFMO, and suppressed saturation magnetization compared to polycrystalline BFMO. To interrogate these previously reported observations of BFMO on STO, we have used a combination of x-ray diffraction, atomic force microscopy, x-ray and neutron reflectivity, and x-ray photoelectron spectroscopy that shows inhomogeneities. The present results show off-stoichiometry on the A-site by incorporation of Sr from the substrate and on the B-site to have %Fe/%Mo > 1 by evolution of BaMoO4. There is an enhanced ordering temperature and magnetic response nearer to the SrTiO3 interface compared to the air interface. Depth dependent strain and microstructure are needed to explain the magnetic response. Holistic considerations and implications are also discussed. [ABSTRACT FROM AUTHOR]

In the calculations of tetragonal BaTiO3, some exchange-correlation (XC) energy functionals such as local density approximation (LDA) have shown good agreement with experiments at room temperature (RT), e.g., spontaneous polarization (PS), and superiority compared with other XC functionals. This is due to the error compensation of the RT effect and, hence, will be ineffective in the heavily strained case such as domain boundaries. Here, ferroelectrics under large strain at RT are approximated as those at 0 K because the strain effect surpasses the RT effects. To find effective XC energy functionals for strained BaTiO3, we propose a new comparison, i.e., a criterion. This criterion is the properties at 0 K given by the Ginzburg-Landau (GL) theory because GL theory is a thermodynamic description of experiments working under the same symmetry-constraints as ab initio calculations. With this criterion, we examine LDA, generalized gradient approximations (GGA), meta-GGA, meta-GGA + local correlation potential (U), and hybrid functionals, which reveals the high accuracy of some XC functionals superior to XC functionals that have been regarded as accurate. This result is examined directly by the calculations of homogenously strained tetragonal BaTiO3, confirming the validity of the new criterion. In addition, the data points of theoretical PS vs. certain crystallographic parameters calculated with different XC functionals are found to lie on a single curve, despite their wide variations. Regarding these theoretical data points as corresponding to the experimental results, analytical expressions of the local PS using crystallographic parameters are uncovered. These expressions show the primary origin of BaTiO3 ferroelectricity as oxygen displacements. Elastic compliance and electrostrictive coefficients are estimated. For the comparison of strained results, we show that the effective critical temperature TC under strain <−0.01 is >1000 K from an approximate method combining ab initio results with GL theory. In addition, in a definite manner, the present results show much more enhanced ferroelectricity at large strain than the previous reports. [ABSTRACT FROM AUTHOR]

Studies of preliminary structural and detailed frequency–temperature dependence of electrical (dielectric, impedance, polarization, and conductivity) properties of Bi/Na-modified barium titanate compound have been performed in this work. The proposed compound has been synthesized by a conventional solid-state sintering route with a composition of (Ba0.8Bi0.1Na0.1)TiO3. The prepared sample has been pre-heated (calcined) at 1050 °C. Preliminary structural analysis using X-ray diffraction method of the calcined powder confirms the phase purity of the prepared barium titanate compound with tetragonal symmetry. The pellet of this compound has been sintered at 1100 °C. Study of the surface morphology of the pellet by scanning electron microscope (SEM) reveals the homogeneous distribution of grains throughout the sample surface. The dielectric study in the temperature range of 25–500 °C at different frequencies (1 kHz to 1 MHz) shows a high dielectric constant and low tangent loss in a wide temperature range. The temperature response of AC conductivity with impedance spectrum confirms the semiconducting nature of the material at high temperatures. The Nyquist plots reflect the grain and grain boundary contributions to the conduction mechanism of this modified BaTiO3 compound. The existence of ferroelectricity at room temperature of the above sample is confirmed by polarization versus electric field (P–E hysteresis loop) measurements. The J versus E characteristic suggests the Ohmic conduction mechanism of the Bi/Na-modified barium titanate compound. All the studied properties conclude that this composition has potential for device application in the electronic industry. [ABSTRACT FROM AUTHOR]

Purpose: Dysphagia impacts many poststroke survivors with wide-ranging prevalence in the acute and chronic phases. One relatively unexplored manifestation of poststroke swallowing impairment is that of primary or co-occurring esophageal dysphagia. The incidence of esophageal dysphagia in this population is unknown despite the shared neuroanatomy and physiology with the oropharynx. We aimed to determine the presence of abnormal esophageal clearance in an acute poststroke sample using the Modified Barium Swallow Impairment Profile (MBSImP) Component 17 (esophageal clearance) as our outcome measure. Method: We performed a retrospective, cross-sectional, cohort study of 57 post-stroke patients with acute, first-ever, ischemic strokes. All participants received a modified barium swallow study (MBSS) using the MBSImP protocol and scoring metrics. Swallowing impairment was determined using a combination of MBSImP scores and Penetration–Aspiration Scale scores. Swallowing outcome measures were collected including Functional Oral Intake Scale and International Dysphagia Diet Standardization Initiative (IDDSI) scores. We performed tests of association and logistic regression analysis to determine if statistically significant associations exist between judgments of esophageal clearance and other swallowing impairments and/or swallowing outcome measures. Results: In our study of poststroke patients who received an MBSS as part of their care, 57.9% had abnormal esophageal clearance. Statistically significant associations were also identified in measures of pharyngeal physiology (MBSImP scores) and swallowing outcome measures (IDDSI scores and alternate means of nutrition). Conclusions: Abnormal esophageal clearance was identified in greater than half of our poststroke patients. There is a dearth of scientific research regarding esophageal function poststroke. While esophageal visualization during the MBSS is not diagnostic of esophageal impairment, it may serve as an indicator for those poststroke patients who require dedicated esophageal testing to best determine the full nature of their swallowing pathophysiology and make the most effective treatment recommendations. [ABSTRACT FROM AUTHOR]

Studies of preliminary structural and detailed frequency–temperature dependence of electrical (dielectric, impedance, polarization, and conductivity) properties of Bi/Na-modified barium titanate compound have been performed in this work. The proposed compound has been synthesized by a conventional solid-state sintering route with a composition of (Ba0.8Bi0.1Na0.1)TiO3. The prepared sample has been pre-heated (calcined) at 1050 °C. Preliminary structural analysis using X-ray diffraction method of the calcined powder confirms the phase purity of the prepared barium titanate compound with tetragonal symmetry. The pellet of this compound has been sintered at 1100 °C. Study of the surface morphology of the pellet by scanning electron microscope (SEM) reveals the homogeneous distribution of grains throughout the sample surface. The dielectric study in the temperature range of 25–500 °C at different frequencies (1 kHz to 1 MHz) shows a high dielectric constant and low tangent loss in a wide temperature range. The temperature response of AC conductivity with impedance spectrum confirms the semiconducting nature of the material at high temperatures. The Nyquist plots reflect the grain and grain boundary contributions to the conduction mechanism of this modified BaTiO3 compound. The existence of ferroelectricity at room temperature of the above sample is confirmed by polarization versus electric field (P–E hysteresis loop) measurements. The J versus E characteristic suggests the Ohmic conduction mechanism of the Bi/Na-modified barium titanate compound. All the studied properties conclude that this composition has potential for device application in the electronic industry. [ABSTRACT FROM AUTHOR]

Due to the uncertain differentiation of neural stem cells (NSCs), replenishing lost neurons by endogenous neural differentiation to repair spinal cord injury (SCI) remains challenging. The electrical stimulation-induced drug release is a promising approach for the localized and controlled release of drugs to regulate the differentiation of NSCs into neurons. Here, we developed Zn-PDA@BT nanoparticles acted as Trojan Horse to enter cells through endocytosis for Zn 2+ -controlled release therapy by the potentials generated by the piezoelectric effect. Due to the presence of polydopamine (PDA), under ultrasound stimulation, the electrical signal derived from the piezoelectric effect of barium titanate nanoparticles can be attracted to the surface of Trojan Horse nanoparticles to facilitate the controlled release of Zn 2+ . And Zn 2+ bonded with PDA can increase the intracellular Zn 2+ concentration within mouse-derived NSCs (mNSCs) to regulate the differentiation of mNSCs, which could enhance excitatory neuronal differentiation and inhibit astrocyte differentiation of mNSCs by activating the TGF-β and p53 pathways. More importantly, this Trojan Horse therapy allowed mNSCs to differentiate into mature neurons in 5 days, while the natural differentiation process took 10 days. Moreover, the transplantation of mNSC-ingested Zn-PDA@BT nanoparticles effectively replenished lost neurons at the damaged site and promoted function recovery after SCI in vivo, demonstrating the great potential of electrical stimulation-induced Zn 2+ release for SCI repair.

During bone tissue regeneration, neovascularization is critical, and the formation of a blood supply network is crucial for bone growth stimulation and remodeling. Previous studies suggest that bioelectric signals facilitate the process of angiogenesis. Owing to their biomimetic electroactivity, piezoelectric membranes have garnered substantial interest in the field of guided bone regeneration. Nevertheless, the knowledge of their influence due to varying surface potentials on the progression of angiogenesis remains ambiguous. Therefore, we proposed the preparation of an electroactive material, P(VDF-TrFE), and investigated its effects on the activity and angiogenic functions of human umbilical vein endothelial cells (HUVECs). The HUVECs were directly cultured on P(VDF-TrFE) membranes with different surface potentials. Subsequently, cell viability, proliferation, migration, tube formation, and expressions of related factors were assessed through appropriate assays. Our results revealed that the negative surface potential groups exerted differential effects on the modulation of angiogenesis in vitro. The P(VDF-TrFE) membranes with negative surface potential exhibited the greatest effect on cellular behaviors, including proliferation, migration, tube formation, and promotion of angiogenesis by releasing key factors such as VEGF-A and CD31. Overall, these results indicated that the surface potential of piezoelectric P(VDF-TrFE) membranes could exert differential effects on angiogenesis in vitro. We present a novel approach for designing bioactive materials for guided bone regeneration. [ABSTRACT FROM AUTHOR]

0.2CaTiO 3 -0.8(Li 0.5 Sm 0.5)TiO 3 -xZnO(x = 0, 0.3, 0.6, 0.9, 1.2 wt%, 0.2CT-0.8LST-xZnO) with orthogonal perovskite structure were fabricated by the solid state method. The effects of ZnO additives on the microwave dielectric properties of 0.2CT-0.8LST ceramics were systematically investigated. With increasing the dopant (x) concentration, the dielectric constant (ε r) and the temperature co-efficient of resonance frequency (τ f) decreased, however, the Q × f values increased. The relationship between vibration mode and microwave dielectric properties was studied using Raman spectroscopy. The Q × f value of ceramics was related to the half-height width of Raman scattering. Narrower Raman scattering peaks corresponded to longer microwave energy propagation decay times and higher Q × f value. Based on X-ray photoelectron spectroscopy (XPS), the addition of Zn2+ ions limited the reduction of Ti4+ cations. The excellent dielectric properties were obtained when x = 1.2 wt% with ε r = 100.25, Q × f = 6525 GHz, and τ f = −12.12 ppm/°C. [ABSTRACT FROM AUTHOR]

Barium hexaferrite is known to be a very good ferromagnetic material. However, it shows very good dielectric properties, i.e., the dielectric constant is comparable to that of the ferroelectric material. However, its crystal symmetry does not allow it to be a ferroelectric material. Hence, the electrical properties have revived the considerable research interest on these materials, not only for academic interest, but also for technological applications. There are a few reports on temperature dependent dielectric behavior of these materials. However, the exact cause of dielectric as well as electrical conductivity is yet to be established. Hence, Al (very good conducting material) substituted barium hexaferrite (BaFe12-xAlxO19, x=0.0-4.0) has been prepared by following the modified sol-gel method to understand the ac and DC electrical properties of these materials. The crystal structure and parameters have been studied by employing the XRD and FTIR techniques. There are two transition temperatures, which have been observed in the temperature dependent ac dielectric and DC resistivity measurement. The response of dielectric behaviors to temperature is similar to that of the ferroelectric material; however, the dielectric polarization is due to the polaron hopping, which is evident from the DC resistivity analysis. Hence, the present observations lead to understand the electrical properties of barium hexaferrite. The frequency dependent dielectric dispersion can be understood by the modified Debye model. More interestingly, the dielectric constant decreases and DC resistivity increases with the increase in the Al concentration, which has the correlation between bond length modifications in the crystal due to substitution. [ABSTRACT FROM AUTHOR]

Complex optical function ε(E)=ε1(E)+iε2(E) components parallel ε॥(E) and perpendicular ε丄(E) to the optic axis are determined in the photon energy range E=2–10 eV for SrxBa1–xNb2O6 single crystals with the composition parameters x=0.40, 0.50, 0.61, 0.65, and 0.75. The spectra are obtained from the evaluation of the ellipsometric data using a relevant optical model which takes into account the optical anisotropy of the crystal and surface imperfection of the measured specimens. We report the parameters necessary to construct the optical function for each studied composition. Additionally, the energies of electronic inter-band transitions are obtained from the analysis in terms of standard analytical line shapes. [ABSTRACT FROM AUTHOR]

We demonstrate the potential of barium hydroxide, Ba(OH)2, as a hole blocking layer on the photovoltaic performance of front- and back-organic/n-type crystalline silicon (n-Si) heterojunction solar cells with poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS). The power conversion efficiency (PCE) of the front-PEDOT:PSS/n-Si heterojunction solar cell was increased from 12.8% for pristine to 13.6% with a 2-nm-thick Ba(OH)2 interlayer at the rear n-Si and aluminum (Al) cathode interface due to the enhanced hole blocking as well as electron injection capability to the Al cathode in the infrared region. PCE was further increased to 14.3% with a short-circuit density JSC of 30.27mA/cm2, an open-circuit voltage VOC of 0.632V, and a fill factor FF of 0.75 using a 20- nm-thick 4,4'-Cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine] as an antireflection layer. PCE of the back-PEDOT:PSS/n-Si heterojunction solar cells was also increased from 4.4% for pristine to 8.1% with a JSC of 33.40mA/cm2, a VOC of 0.573V, and an FF of 0.423 by inserting a 2-nm-thick Ba(OH)2 layer at the front-Al and isotropically textured n-Si interface. These findings imply that Ba(OH)2 has great potential as an efficient hole-blocking layer for both front- and back- PEDOT:PSS/n-Si heterojunction solar cells. [ABSTRACT FROM AUTHOR]

We report structural, compositional, and magnetic properties for a commercially available doped barium hexaferrite material produced by Temex Ceramics. The material is designed to absorb electromagnetic radiation near the upper edge of the Ku frequency band (∼ 18 GHz) and may serve as an important component to microwave circuitry. To aid in the development of such circuits that may utilize this or similar materials, we present results of the material properties of the raw starting powder, sintered pucks, and in the form of a film deposited by aerosol deposition. We find that the structural and magnetic properties are consistent with the parent compound, barium hexaferrite. Samples sintered at 1250 °C show some degree of preferred magnetic and structural orientation. Chemical analysis indicates that a titanium dopant has been added and that the material demonstrates broad absorption above 13 GHz that improves with sintering temperature. To our knowledge, this is the first report on the properties of this commercially available material. [ABSTRACT FROM AUTHOR]

ZnO-Bi2O3-metal oxide systems are successfully utilized as varistors due to their non-linear I-V behavior. The electrical properties of ZnO-based varistors strongly depends on grain boundary phase composition and microstructural features. In this study, ZnO-based varistors containing different amount of CuO (0–2 mol%) were sintered by conventional and spark plasma sintering (SPS) methods, which resulted different I-V characteristics. While the samples sintered by SPS method were observed to have smaller grain size, more homogenous microstructure and higher density, grain boundary thickness reduced due to removal of bismuth, which was the result of high vacuum environment during sintering step. Since the barrier thickness of SPSed samples decreased, a lower breakdown electrical field (Eb) value was recorded in comparison to conventionally sintered samples. It was also detected that Eb values of both conventional and SPS samples increased with increasing CuO content. [ABSTRACT FROM AUTHOR]

We report the first example of a perovskite sulfate [Na3(H2O)]Fe(SO4)3. Further structure modulation, by dimensional reduction or ligand extension, has resulted in two related layered perovskite-like compounds Na6Fe(SO4)4 and Na12Fe3(SO4)6F8. Taken together, these results open up a more general strategy for the future design of more complex perovskite-related materials. [ABSTRACT FROM AUTHOR]