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Background: Use of heart failure-exacerbating medications (HFEMs) may lead to preventable episodes of acute decompensated heart failure (HF). HFEMs use is common in patients with HF, and there may be opportunities to reduce their use from the emergency department (ED). Methods: We performed an observational study on patients with HF presenting to EDs within a healthcare system between 1 January 2016 and 31 December 2020. Patients with chronic HF were identified using diagnostic codes within the electronic health record. The cohort was restricted to ambulatory (i.e., discharged to home) ED encounters. Medications, either ordered in the ED or prescribed at ED discharge, were extracted from the medication administration record and identified as potential HFEMs based on the 2016 American Heart Association Scientific Statement. Descriptive statistics were used to summarize the prevalence of HFEM use during ambulatory ED encounters. Exploratory analyses to identify correlates of HFEM use were performed. Results: The study cohort included 23,907 ED encounters. ED administration or prescription of HFEMs occurred during 20% of ambulatory ED encounters. HFEM administration in the ED (17%) was more common than HFEM prescription at ED discharge (6%). The most common HFEMs administered in the ED included nonsteroidal anti-inflammatory drugs (11%) and albuterol (7%). Conclusion: HFEM use is common in patients with HF seeking ED care, occurring in roughly one-fifth of ambulatory ED encounters. There may be opportunities to optimize medication use among patients with HF in the ED. [ABSTRACT FROM AUTHOR]

Key Points: Question: Can novice clinicians accurately estimate gestational age using a low-cost, battery-powered ultrasonography probe with integrated artificial intelligence (AI) image interpretation? Findings: This prospective study enrolled 400 pregnant individuals with due dates confirmed by first-trimester ultrasonography. At follow-up visits randomly assigned throughout gestation, novice clinicians using an AI-enabled device estimated gestational age as accurately as credentialed sonographers using traditional ultrasonography devices (difference, 0.2 days). Meaning: Obstetrical care in low-resource settings may benefit from reliable gestational age assessment using AI integration with point-of-care ultrasonography. Importance: Accurate assessment of gestational age (GA) is essential to good pregnancy care but often requires ultrasonography, which may not be available in low-resource settings. This study developed a deep learning artificial intelligence (AI) model to estimate GA from blind ultrasonography sweeps and incorporated it into the software of a low-cost, battery-powered device. Objective: To evaluate GA estimation accuracy of an AI-enabled ultrasonography tool when used by novice users with no prior training in sonography. Design, Setting, and Participants: This prospective diagnostic accuracy study enrolled 400 individuals with viable, single, nonanomalous, first-trimester pregnancies in Lusaka, Zambia, and Chapel Hill, North Carolina. Credentialed sonographers established the "ground truth" GA via transvaginal crown-rump length measurement. At random follow-up visits throughout gestation, including a primary evaluation window from 14 0/7 weeks' to 27 6/7 weeks' gestation, novice users obtained blind sweeps of the maternal abdomen using the AI-enabled device (index test) and credentialed sonographers performed fetal biometry with a high-specification machine (study standard). Main Outcomes and Measures: The primary outcome was the mean absolute error (MAE) of the index test and study standard, which was calculated by comparing each method's estimate to the previously established GA and considered equivalent if the difference fell within a prespecified margin of ±2 days. Results: In the primary evaluation window, the AI-enabled device met criteria for equivalence to the study standard, with an MAE (SE) of 3.2 (0.1) days vs 3.0 (0.1) days (difference, 0.2 days [95% CI, −0.1 to 0.5]). Additionally, the percentage of assessments within 7 days of the ground truth GA was comparable (90.7% for the index test vs 92.5% for the study standard). Performance was consistent in prespecified subgroups, including the Zambia and North Carolina cohorts and those with high body mass index. Conclusions and Relevance: Between 14 and 27 weeks' gestation, novice users with no prior training in ultrasonography estimated GA as accurately with the low-cost, point-of-care AI tool as credentialed sonographers performing standard biometry on high-specification machines. These findings have immediate implications for obstetrical care in low-resource settings, advancing the World Health Organization goal of ultrasonography estimation of GA for all pregnant people. Trial Registration: ClinicalTrials.gov Identifier: NCT05433519 This prospective diagnostic study examines the accuracy of an AI-enabled ultrasonography tool in estimating gestational age when used by those with no prior training in sonography. [ABSTRACT FROM AUTHOR]

Nickel-based hardfacing alloy bushes are used in dynamic moving components inside fast breeder reactors. Due to the difficulties associated with their fabrication through casting or weld deposition, laser rapid manufacturing (LRM) was attempted. In this work, microstructure development and phase selection in laser additive manufactured Ni-based hardfacing alloy bushes are investigated. The as-fabricated bushes had a uniform, defect-free microstructure perpendicular to the material build direction, whereas microstructural heterogeneity could be detected parallel to the build direction due to coarsening of precipitates. Overall microstructure was dominated by γ-Ni, γ-Ni + Ni3B anomalous and lamellar eutectic and Ni–B–Si lamellar eutectic constituents. In addition, Cr-rich borides and carbides were also found. Phase property diagrams and Scheil's non-equilibrium solidification simulated using ThermoCalc® provided supporting insights into the phase selection phenomena under rapid cooling conditions. Microstructure of LRM Ni-based hardfacing alloy bushes was quite distinct from weld deposited ones and is analyzed in terms of a non-equilibrium eutectic solidification reaction occurring in Ni–Cr–B–C–Si–Fe multicomponent alloy system due to rapid cooling. [ABSTRACT FROM AUTHOR]

Patients with heart failure (HF) often suffer from multimorbidity. Rapid assessment of multimorbidity is important for minimizing the risk of harmful drug-disease and drug-drug interactions. We assessed the accuracy of using the electronic health record (EHR) problem list to identify comorbid conditions among patients with chronic HF in the emergency department (ED). A retrospective chart review study was performed on a random sample of 200 patients age ≥65 years with a diagnosis of HF presenting to an academic ED in 2019. We assessed participant chronic conditions using: (1) structured chart review (gold standard) and (2) an EHR-based algorithm using the problem list. Chronic conditions were classified into 37 disease domains using the Agency for Healthcare Research Quality's Elixhauser Comorbidity Software. For each disease domain, we report the sensitivity, specificity, positive predictive value, and negative predictive of using an EHR-based algorithm. We calculated the intra-class correlation coefficient (ICC) to assess overall agreement on Elixhauser domain count between chart review and problem list. Patients with HF had a mean of 5.4 chronic conditions (SD 2.1) in the chart review and a mean of 4.1 chronic conditions (SD 2.1) in the EHR-based problem list. The five most prevalent domains were uncomplicated hypertension (90%), obesity (42%), chronic pulmonary disease (38%), deficiency anemias (33%), and diabetes with chronic complications (30.5%). The positive predictive value and negative predictive value of using the EHR-based problem list was greater than 90% for 24/37 and 32/37 disease domains, respectively. The EHR-based problem list correctly identified 3.7 domains per patient and misclassified 2.0 domains per patient. Overall, the ICC in comparing Elixhauser domain count was 0.77 (95% CI: 0.71-0.82). The EHR-based problem list captures multimorbidity with moderate-to-good accuracy in patient with HF in the ED. [ABSTRACT FROM AUTHOR]

Bipyramidal distortions play the governing role in physical properties of RMnO3 multiferroics. We have carried out angle-dispersive high pressure synchrotron X-ray diffraction experiments on hexagonal HoMnO3 to find the evolution of bipyramidal parameters upon external compression. It is found that the average bond-lengths and bond-angles between Mn and O atoms depict significant reduction, which results in the distortion in MnO5 bipyramidal structure at high pressures. Further, since subtle variations in these distortions are used to compare the properties of hexagonal RMnO3 manganite series, in-situ low temperature infrared spectroscopic studies of 10% Dy-doped HoMnO3 have been carried out to study the effect of further increase in R-site cationic radius on MnO5 deformations. It is found that the phonon modes specifically related to the motion of Mn and O atoms in ab-plane display irregularities near magnetic transition temperatures (TN and TSR) via spin phonon coupling. Even a small increase in average ionic radius of rare-earth atom suppresses this anomalous behaviour and follows the trend of undoped hexagonal rare-earth manganites. [ABSTRACT FROM AUTHOR]

High pressure behaviour of core/shell amorphous carbon (a-C) nanostructures was studied using synchrotron X-ray diffraction (XRD) and Raman spectroscopy up to ~25 GPa. These nanostructures having spherical a-C shells with γ-Fe2O3 nanoparticles at the core were synthesized by catalyst-assisted lamp black method. The typical size of core (γ-Fe2O3)/shell (a-C) is ~5 nm/20 nm. Comparative XRD of the core (γ-Fe2O3) in opened- and closed-shell (a-C) shows that the carbon shells do not fully transmit the applied high pressure inwards, under hydrostatic conditions. Raman spectroscopy shows that the graphitic G-mode blue shifts reversibly with applied pressure with a coefficient ~3.5 cm−1 GPa−1, which is ~25 to 40% less than that for graphite and carbon nanotubes. It is suggested that a rigid and crosslinked structure of the carbon shell might be lossy for the observed pressure drop. [ABSTRACT FROM AUTHOR]

Doping plays a vital role in tuning the carrier concentration and also influences various electronic properties in semiconductors. In addition to tuning the electronic properties of semiconductors, impurities also affect vibrational properties. We report the local vibrational modes (LVMs) in N-doped n-type 6H-SiC. New phonon modes are observed in the low-temperature range. Unlike lattice phonons, LVMs are localized in both the real space and frequency domains and give rise to a distinct signature in the Raman spectra. In the present study, LVMs in N-doped 6H-SiC are identified as N atom vibrations with the help of lattice dynamical calculations of the phonon density of states using generalized gradient approximation. Moreover, the stability of the SiC is investigated for a wide temperature range signifying its application in micro-electro-mechanical systems technology. Therefore, the present study provides insight for understanding both lattice phonons and the impurity-induced vibrational modes using Raman spectroscopic analysis in corroboration with the calculation of phonon density of states. [ABSTRACT FROM AUTHOR]

Bis(3,5-dinitro-4-aminopyrazolyl) methane (BDNAPM) is a new insensitive secondary explosive with a high thermal decomposition temperature. The higher thermal stability and insensitivity towards impact and friction make BDNAPM potentially useful in mining and fracking industry. The sensitivity of explosives is correlated to the phonon modes of the material. Pressure and temperature induced phase transformation study of BDNAPM is important for applications because different phases show different detonation properties and sensitivity towards external stimuli. We have calculated the vibrational frequencies of BDNAPM molecule using Gaussian software, phonon frequencies of the crystal using density functional perturbation theory, and assigned the modes. We report the pressure dependent phase transformations in BDNAPM using Raman spectroscopy and X-ray diffraction. Appearance of new modes, especially in the external mode region indicates a structural phase transformation at 3.3 GPa. Also, many internal and external modes show discontinuity above 2.8 GPa. The changes in the bands like splitting, discontinuity and red-shift occur mainly for bands corresponding to the N–H, C–H and N–O movements, indicating change in the hydrogen bonding that could lead to a reorientation of the molecule and a structural phase transformation beginning at 3.3 GPa. Pressure dependent X-ray diffraction results corroborate the Raman spectroscopic results. The crystal lattice exhibits anisotropic compression under pressure. We were able to fit the ambient orthorhombic structure to the XRD patterns up to 2.6 GPa and then the structure transformed into a monoclinic phase (space group P21/n) with a 13% volume reduction. Bulk modulus is obtained by fitting third-order Birch Murnaghan equation of state to the PV data for the ambient and high-pressure phase. [ABSTRACT FROM AUTHOR]

We have used X-ray diffraction (XRD) to investigate strain partitioning between an epitaxial layer and the substrate as a function of temperature, where the substrate (Si) and the epilayer material (Ag) have large thermal expansion coefficient (a) mismatch. The Ag/Si(111) system undergoes morphological changes upon heating, and the larger and taller islands are formed exposing more substrate surfaces. Sample heating was carried out under nitrogen flow. At >300 °C, the Si(111) diffraction peak splits into three. One of these components conforms to the thermal expansion of bulk Si. The other two components correspond to a highly nonlinear decrease and increase of Sid( 111) planar spacing. The decreasing component has been associated with strained Si under Ag and the increasing component with strained Si under SiO2, which has been formed partly prior to the XRD experiment and partly during sample heating. The opposite trends of these two Si-d(111) components are because of the larger value of a for Ag (7 times) and smaller for SiO2 (1/5th) compared to Si. The out-of-plane strain partitioning has been such that at room temperature, the Si substrate is unstrained and the strain in Ag is ~0.3%. At 800 LC, Ag is practically relaxed, while Si under Ag is ~-0.7% strained. A temperature dependent strain partitioning factor has been introduced to fit the data. [ABSTRACT FROM AUTHOR]

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 Fe2TiSn, Cr is introduced systematically at Ti site that conforms to the chemical formula Fe 2 Ti 1 - x Cr x 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 Fe2CrSn. Our experimental study using synchrotron X-ray diffraction reveals that only compositions with x ≤ 0.25 yield phase pure L2 1 cubic structures. The non-magnetic ground state of Fe2TiSn gets dramatically affected upon inclusion of Cr giving rise to a localized magnetic moment in the background of Ruderman–Kittel–Kasuya–Yosida (RKKY) correlations. The ferromagnetic interactions begin to dominate for x = 0.25 composition. Results of its resistivity and magnetoresistance (MR) measurement point towards a half-metallic ground state. The calculation of exchange coupling parameter, J ij , and orbital projected density of states that indicate a change in hybridization between 3d and 5p orbital, support the observations made from the study of local crystal structure made using the extended X-ray absorption fine structure spectroscopy. Our findings here highlight an interesting prospect of finding half-metallicity via band structure tailoring for wide application in spintronics devices. [ABSTRACT FROM AUTHOR]

The intriguing functional nature of ceramics containing rare earth sesquioxide (RES) is associated with the type of polymorphic structure they crystallize into. They prefer to be in the cubic, monoclinic or hexagonal structure in the increasing order of cation size, RRE. Since the functional properties of these ceramics varies with RRE, temperature and pressure, a systematic investigation delineating the cation size effect is indispensable. In the present work we report the structural stability and compressibility behaviour of the RES ceramics, (Eu1−xLax)2O3, of RESs with dissimilar structure and significant difference in cationic radii. The selected compositions of (Eu1−xLax)2O3 have been studied using the in-situ high pressure synchrotron X-ray diffraction and the structural parameters obtained through Rietveld refinement. The cubic structure, which is stable for 0.95 Å ≤ RRE < 0.98 Å at ambient temperature and pressure (ATP), prefers a cubic to hexagonal transition at high pressures. The biphasic region of cubic and monoclinic structure, which is stable for 0.98 Å ≤ RRE < 1.025 Å at ATP, prefers a cubic/monoclinic to hexagonal transition at high pressures. Further, in the biphasic region of monoclinic and hexagonal structure, observed for 1.025 Å ≤ RRE < 1.055 Å, the monoclinic phase is found to be progressing towards the hexagonal phase with increasing pressure. The pure hexagonal phase obtained for 1.055 Å ≤ RRE ≤ 1.10 Å is found to be structurally stable at high pressures. The bulk moduli are obtained from the Birch–Murnaghan equation of state fit to the compressibility data and its dependance on the cation size is discussed. The microstrain induced by the difference in cation size causes an internal pressure in the crystal structure leading to a reduction in the bulk modulus of x = 0.2 and 0.6. A pressure–concentration (P–x) phase diagram upto a pressure of 25 GPa is constructed for (Eu1−xLax)2O3. This would provide an insight to the fundamental and technological aspects of these materials and the RESs in general. [ABSTRACT FROM AUTHOR]

We have investigated the structure, transport and magnetic properties of Ni2MnSb0.5Al0.5 Heusler alloy. Structural analysis using x-ray diffraction and scanning electron microscopy has confirmed Ni2MnSb0.5Al0.5 to be a natural composite of Ni2MnSb and Ni2MnAl phases, regardless of annealing conditions. This composite has a dendritic microstructure formed by the phase separation during solidification. The electronic phase separation was confirmed using x-ray near edge absorption spectroscopy, recorded at Mn and Ni K-edge and supported by ab-initio calculations of the same using multiple scattering theory. A thorough characterization of this novel composite form of Ni2MnSb0.5Al0.5 Heusler alloy has been carried out by recording its magnetic and transport properties including electrical resistivity, thermal conductivity, and heat capacity. The composite micro-structure of this system plays a crucial role in drastically reducing its thermal conductivity value, while maintaining its metallic character. Unlike many oxide composites, the magnetic properties of the Ni2MnSb0.5Al0.5 cannot be considered as the volume average of the characteristics of the two phases, rather it shows a long range ferromagnetic order with Curie temperature of 334 K and magnetic moment of 2.52 /f.u. [ABSTRACT FROM AUTHOR]

Solid solutions, (Eu1−xLax)2O3 (0 ≤ x ≤ 1), of the rare earth sesquioxides Eu2O3 and La2O3 have been prepared by a simple soft chemistry approach. The composition and morphology of the as‐synthesized oxides have been characterized using energy‐dispersive spectroscopy and scanning electron microscopy. The particles are of irregular shape and submicrometre size. In order to understand the structural evolution as a function of composition, angle‐dispersive X‐ray diffraction measurements have been carried out and the structural parameters have been obtained through Rietveld refinement. A structural phase transition from the cubic (C‐type) to the monoclinic (B‐type) structure and subsequently to the hexagonal (A‐type) structure was observed with an increasing substitution of La. A detailed analysis of the transition boundaries in terms of the average cationic radius, RRE, shows that the onset of the C → B transition is at RRE = 0.980 Å, whereas the B → A transition occurs at RRE = 1.025 Å. A biphasic region of cubic and monoclinic structures is observed for 0.2 ≤ x ≤ 0.4 and one of monoclinic and hexagonal structures is observed for 0.5 ≤ x ≤ 0.6. The microstrain induced by the difference in size of the rare earth cations introduces a substitutional disorder in the crystal structure, which is a plausible cause of the observed phase transitions in these oxides. A structural phase transition from a cubic to a monoclinic structure and subsequently to a hexagonal structure is observed with increasing cation size in the rare earth sesquioxide (Eu1−xLax)2O3. The microstrain and substitutional disorder in the crystal structure are considered to be the causes of the observed phase transition. [ABSTRACT FROM AUTHOR]

This paper presents the results of an experimental study to investigate the structural and microchemical characteristics of an equiatomic CrFeNbNiV alloy. XRD analysis of CrFeNbNiV alloy, revealed a predominant NbCrNi type HCP Laves phase conjoined with two minor tetragonal and BCC phases. Detailed microstructural investigations using electron microscopy techniques also substantiated the presence of the above mentioned phases. The structure of Laves phase in this alloy is determined ab initio for the first time using Precession Electron Diffraction technique which was in agreement with the Rietveld analysis of XRD pattern. The formation of intermetallic Laves phase was understood based on theoretical phase stability and average d- orbital energy level Md¯ value calculations. The alloy in the 'as cast' condition exhibited a very high value of hardness (~ 1500 Hv). No change in the microstructure and hardness was observed on annealing at high temperatures even up to 1373 K (1100 °C). [ABSTRACT FROM AUTHOR]

Removal of pathological lesions from the mandible can leave a disfiguring appearance in addition to compromising the function of speech and mastication. It therefore becomes imperative to replace the lost part with bone grafts. Autogenous bone grafts-vascularised and non-vascularised, have been in vogue for the same. The probability of using the same resected bone after removal of all pathology has been done for a long time with mixed results in terms of uptake and viability. This paper presents a case of the use of autoclaved resected bone being used for reconstructing the mandible. [ABSTRACT FROM AUTHOR]

We present the results of synchrotron X-ray diffraction (XRD) measurements on powdered single-crystal samples of BaFe2 − xRu xAs2, as a function of Ru content, and as a function of temperature, across the spin-density wave transition in BaFe1.9Ru0.1As2. The Rietveld refinements reveal that with Ru substitution, while the a-axis increases, the c-axis decreases. In addition, the variation of positional coordinates of As ( zAs), the Fe-As bond length and the As-Fe-As bond angles have also been determined. In the sample with x = 0.1, temperature-dependent XRD measurements indicate that the orthorhombicity shows the characteristic increase with a decrease in temperature, below the magnetic transition. It is seen that the c-axis, the As-Fe-As bond angles, Fe-As bond length and positional coordinates of the As show definite anomalies close to the structural transition. The observed anomalies in structural parameters are analysed in conjunction with restricted geometric optimization of the structure using ab initio electronic structure calculations. [ABSTRACT FROM AUTHOR]

Primary hyperparathyroidism is due to parathyroid adenoma (80-85%), hyperplasia (10-15%), carcinoma (2-3%) of cases. The most common presentation is asymptomatic hypercalcemia. Multiple pathological fractures, nephrocalcinosis as a presenting feature of primary hyperparathyroidism due to parathyroid adenoma is extremely rare at the age of 19 years. A case of parathyroid adenoma with multiple fractures of left femur, renal calculi, nephrocalcinosis, weight loss, constipation, dyspepsia abdominal pain was presented. The case was investigated completely with biochemical investigations, X-ray of forearm bones and femur, ultrasonography of neck and abdomen, CT scan of neck and abdomen, MRI scan, Scintigraphy of the neck. Right inferior parathyroid adenoma was diagnosed and confirmed by histopathological examination after excision. The post operative serum calcium levels became normal. [ABSTRACT FROM AUTHOR]

Nanophase of Ga2O3 has potentially important applications in photocatalysis. We report the synthesis of nanophase of the metastable γ- and stable β-Ga2O3 and demonstrate that it is possible to prepare a continuously varying mixture starting from the pure metastable γ- to the pure β-phase. This is achieved by employing a facile and reliable combustion route, using urea as a fuel. Typical grain sizes, as estimated from XRD studies, are about 3 nm. Given the importance of surface chemistry for potential applications, thermogravimetric coupled with mass spectrometry is used in conjunction with FTIR to elucidate the chemistry of the adsorbed surface layer. Studies on the γ-Ga2O3 phase indicate the occurrence of weight loss of 8.1% in multiple steps. Evolved gas analysis and FTIR studies show presence of physisorbed H2O molecules and chemisorbed –(OH) ions bonded to active surface states and accounts predominantly for the observed weight loss. [ABSTRACT FROM AUTHOR]