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Through comprehensive data analysis, we demonstrate that a χ(2)-induced artifact, arising from imperfect balancing in the conventional electro-optic sampling detection scheme, contributes significantly to the measured signal in 2D Raman–THz spectroscopy of non-centrosymmetric materials. The artifact is a product of two 1D responses, overwhelming the desired 2D response. We confirm that by analyzing the 2D Raman–THz response of an x-cut beta barium borate crystal. We furthermore show that this artifact can be effectively suppressed by implementing a special detection scheme. We successfully isolate the desired third-order 2D Raman–THz response, revealing a distinct cross-peak feature, whose frequency position suggests the coupling between two crystal phonons. [ABSTRACT FROM AUTHOR]

We report a first-principles study of the linear electro-optic or Pockels effect in SrxBa1-xNb2O6 (SBN). SBN is an attractive material for building electro-optic modulators in silicon photonics as it has one of the highest known Pockels coefficients and can be integrated on Si. We investigate the microscopic mechanism behind the giant Pockels effect and find that the optical phonon contribution dominates the electro-optic response. We identify the phonon modes that have a significant contribution to the Pockels response and discuss the microscopic origin of the response. In addition, we analyze the contribution of the converse piezoelectric effect to the Pockels response. We find good agreement when comparing our results to available experiment. [ABSTRACT FROM AUTHOR]

Barium Oxyfluoride plays an important role, as a precursor species, in the nucleation and growth of YBa2Cu3O7− δ (YBCO) via the low fluorine metal organic decomposition (MOD low-fluorine) route. In this contribution, we present a study on the thermodynamics of oxyfluoride by processing experimental data on YBCO growth on LaAlO3 (LAO) substrates. The analysis allows one to determine the standard enthalpy and the standard entropy changes for oxyfluoride formation from barium oxide and barium fluoride. To identify the thermodynamically more favorable route to oxyfluoride formation in the MOD low-fluorine process, the free energy change for the formation of the precursor, through reactions involving gas water, has been determined. The free energy of formation via fluoride and water indicates higher stability of oxygen rich oxyfluoride for P HF 2 P H 2 O < 10 − 6 . In the framework of nucleation theory, the present results are needed to study the effect of precursor composition on film orientation. [ABSTRACT FROM AUTHOR]

In this paper, the influence of antimony concentration and different sintering techniques on the structural, microstructural, and electrical properties of antimony-doped barium stannate, BaSn 1- x Sb x O 3 (BSSO, x = 0.00, 0.04, 0.06, 0.08 and 0.10) was investigated. BSSO-based ceramic samples were obtained by conventional and spark plasma sintering. The XRD analysis confirmed the single-phase, cubic BaSnO 3 lattice system in all conventionally sintered samples. Apart from the dominant cubic phase, the spark plasma sintering conditions led to the formation of a secondary phase, Ba 2 SnO 4 , in all samples. FESEM analysis revealed the presence of low angle grain boundaries (LAGBs) in BSSO samples with high antimony concentration (x = 0.08), independently of the sintering technique. However, the fraction of LAGBs is significantly higher in the BaSn 0.92 Sb 0.08 O 3 - SPS sample due to the simultaneous exposure of the conductive sample to the effects of high temperature and pressure during sintering process. These boundaries have low activation energy and allow free charge carrier transport through the grain boundary region. The high dopant concentration and the presence of large fraction of LAGBs in BaSn 0.92 Sb 0.08 O 3 - SPS sample reflected on its electrical properties through low and almost temperature-independent electrical resistivity in the temperature range of 25–150 °C. [ABSTRACT FROM AUTHOR]

Based on the high resolution and high signal-to-noise spectra, we derived the chemical abundances of 20 elements for 20 barium (Ba-) stars. For the first time, the detailed abundances of four sample stars, namely HD 92482, HD 150430, HD 151101, and HD 177304 have been analysed. Additionally, Ba element abundance has been measured using high-resolution spectra for the first time in six of the other 16 sample stars. Based on the [s/Fe] ratios, the Ba-unknown star HD 115927 can be classified as a strong Ba-star, while the Ba-likely star HD 160538 can be categorized into a mild Ba-star. Consequently, our sample comprises three strong and 17 mild Ba-stars. The light odd-Z metal elements and Fe-peak elements exhibit near-solar abundances. The [ |$\alpha$| /Fe] ratios demonstrate decreasing trends with increasing metallicity. Moreover, the abundances of neutron-capture (n-capture) elements show significant enhancements in different degrees. Using a threshold of the signed distances to the solar rapid-process (r-process) abundance pattern |$d_{\rm s}$| = 0.6, we find that all of our sample stars are normal Ba-stars, indicating that the enhancements of slow-process (s-process) elements should be attributed to material transfer from their companions. We compare the observed n-capture patterns of sample stars with the FRUITY models, and estimate the mass of the Thermally-Pulsing Asymptotic Giant Branch stars that previously contaminated the Ba-stars. The models with low masses can successfully explain the observations. From a kinematic point of view, we note that most of our sample stars are linked with the thin disc, while HD 130255 may be associated with the thick disc. [ABSTRACT FROM AUTHOR]

Changes in phenology are a conspicuous fingerprint of climate change, leading to fears that phenological mismatches among interacting species will be a leading cause of population declines and extinction. We used quantile regression to analyze museum collection data and estimate changes in the phenological overlap of Baltimore checkerspot butterflies and 12 common nectar plant species over several decades in two geographic regions. We combined these museum data with field estimates of each species' flower density and nectar sugar production to estimate changes in resource availability caused by shifts in phenological overlap. Phenological overlap (measured as the proportion of plant flowering during the flight period of an average butterfly) decreased through time, primarily because the flowering period of nectar plants was longer, but the flight period of butterflies was shorter in recent years. Our study was also motivated by the hypothesis that phenological mismatches may be more severe in the southern region due to a midsummer dearth in floral resources, but this hypothesis was not supported by our data. Although phenological overlap was somewhat smaller in the southern region, changes in overlap through time were similar in both regions. When phenological overlap was weighted by nectar sugar production of different species, the overlap increased in the southern region but decreased in the northern region (the opposite of our prediction). Overall, nectar resources were much more abundant at study sites in our northern region than in our southern region, possibly due to differences in land management. Our study demonstrates the complexities of phenological mismatch of interacting species and highlights that phenological changes may have small impacts on population viability. [ABSTRACT FROM AUTHOR]

Lithothamnion mirabile is currently considered a heterotypic synonym of L. muelleri. Three of the 14 specimens and additional fragments comprising the holotype of L. mirabile were selected for DNA sequencing as they best matched the protologue. The three 263-base pair rbcL sequences were distinct from each other, and were classified in the order Hapalidiales, but none were resolved in Lithothamnion. One sequenced specimen belongs in Roseolithon and was selected as the lectotype; thus we propose R. mirabile (Foslie) comb. nov. Another sequenced specimen groups with Phymatolithopsis and the third is well resolved in an undescribed genus of Hapalidiales sister to Boreolithothamnion. [ABSTRACT FROM AUTHOR]

The emergence of high-entropy perovskite materials provides a new research idea to solve the problem of high remnant polarization and low recoverable energy storage density (W rec) of relaxor ferroelectrics. In this study, barium-based high-entropy perovskite oxides Ba(Zr 0.2 Sn 0.2 Hf 0.2 Nb 0.2 Ti 0.2)O 3 (BZSHNT) were introduced into the 0.94Na 0.5 Bi 0.5 TiO 3 -0.06BaTiO 3 (BNT-6BT) ceramic by the conventional solid state sintering method. The 0.2BZSHNT doped BNT-6BT ceramic demonstrates significantly improved W rec of 3.57 J/cm3 and a high efficiency of 81.6 % compared to those of the BNT-6BT ceramic, which is only 0.5 J/cm3 and 60 % respectively. The doped BZSHNT refines the hysteresis loops and drastically reduces the remnant polarization, which lead to the increase of the polarization difference. The 0.8(BNT-6BT)-0.2BZSHNT ceramics show high discharge energy density, good temperature stability (25–200 °C), excellent frequency stability (10–300 Hz) and superior discharge rate (t 0.9 = 83 ns) because of its increased TiO 6 lattice distortion, atomic disorder, relaxation degree and band gap, as well as the disruption of the long-range ordered ferroelectric domains. Our findings make BNT-6BT doped BZSHNT based ceramics one of the most promising lead-free dielectric energy storage candidates. [ABSTRACT FROM AUTHOR]

In cold methanol, energetic ionic liquid 1-n-propyl-3-vinyl-imidazol-1-ium perchlorate, 1, crystallizes in the presence of excess Ba(ClO4)2, 2, into tetrakis 1-propyl-3-vinyl-imidazol-1-ium·barium hexa-perchlorate, 3. Crystals of 3, with molecular formula (C8H13N2)4·BaCl6O24, are colorless and monoclinic, with space group P21/c. The crystal structure is characterized by a dodecahedral coordination around the barium atom, with each perchlorate chelating Ba2+ in a κ2O,O' fashion, and the Ba(ClO4)64− anion is surrounded by four imidazolium cations. [ABSTRACT FROM AUTHOR]

Molecular studies have contributed to the taxonomy of carrageenan-producing Kappaphycus spp. and Eucheuma denticulatum. However, unresolved species complexes and the lack of standardization in the use of genetic markers impede the identification of specimens and the delineation of a robust taxonomic framework. Here, nine molecular markers (cox1, cox2–3 spacer, cox2, cox3, COB, ITS, psbA, UPA and rbcL) were used to generate a multilocus phylogeny for 113 fresh eucheumatoid samples and four herbarium specimens. Analyses of species delineation and genetic distances confirmed the monophyly of currently accepted taxa. These analyses suggest that clades previously reported as K. striatus KS1 and KS2 are conspecific, and that E. denticulatum EDA 'spinosum' and EDB 'endong/cacing' are also conspecific. The results also unveiled possible new taxa from Hawaii and Indonesia. Each molecular marker and combinations thereof were assessed with regard to species identification, ease of amplification and sequencing, and haplotype characterization. All genetic markers recorded at least 94% success in the amplification and sequencing of fresh specimens, with cox1 being the most phylogenetically informative. Automatic partitioning, phylogenetic and tree-based assessments showed cox1, cox2–3 spacer, cox2 and rbcL were able to correctly identify species while cox1+ rbcL, COB+rbcL, cox2+ rbcL or cox1+ COB+rbcL trees best represented the phylogeny with consistently high nodal support. Among individual markers, cox1 identified the greatest number of haplotypes, while UPA, partial rbcL (750 bp), ITS, cox3 and cox2–3 spacer were able to retrieve information from herbarium specimens of 12–16 years of age. These molecular results provide a basis for a database essential for the taxonomic framework, cultivar development and germplasm conservation of eucheumatoids. Highlights: Mitochondria cox1, cox2–3 spacer, cox2 and plastid rbcL can be used for species identification and cox1 for haplotype detection of eucheumatoids. cox1+rbcL, COB+rbcL, cox2+rbcL or cox1+COB+rbcL are the most cost-effective molecular markers for phylogenetic inference. The most comprehensive up to date multilocus phylogeny of Kappaphycus spp. and Eucheuma denticulatum is presented. [ABSTRACT FROM AUTHOR]

Societal Impact Statement: Herbaria, as collections of preserved plants, contain large amounts of data both in the labels and the specimens themselves, which can be applied in different study fields. A literature review was conducted to discover how the uses of herbaria have evolved over time since records began. This analysis revealed insights into how herbaria are presently used. Uses include traditional taxonomic review, as well as advanced technological tools, which are being applied to herbaria material to address societal and global challenges and therefore contribute to decision‐making in conservation. Summary: Herbaria as collections of preserved plants contain large amounts of data and prominent information, both on the labels and on the specimens themselves. There are 400 million specimens preserved in herbaria worldwide, with great potential for studies in conservation and effects of global change on plants. (1) In this paper, we investigate the array of herbaria uses through a systematic review of the scientific literature in SCOPUS covering the period 1842–2022. (2) We reviewed a total of 2900 papers and classified them in different areas of knowledge, as well as the taxonomic level studied. (3) Our results show that taxonomic use is the most relevant over time. This taxonomic use, together with the use as primary source of plant diversity data, is essential for documenting, planning, and acting on the conservation of threatened plants. Furthermore, our results have shown that new and diverse uses have emerged since 1990, mostly related to ecological issues, as herbaria provide a historical record of plant diversity and distribution, as well as their ecological and evolutionary responses, allowing scientists to track changes over time. (4) This contributes to improve the knowledge of biodiversity and to increase the effectiveness of conservation strategies and policies, which are a priority to address on going global change. Therefore, our study shows the relevance and potential of herbaria in ecology, including new or forthcoming uses, which are different from the uses originally intended by collectors. Thus, their preservation is critical as the unique and exceptional record for the knowledge of changes in biodiversity over space and time. [ABSTRACT FROM AUTHOR]

In this work, 5‐ferrocenyl‐dipyrromethane (Fc‐DPM) synthesized from the pyrrole and ferrocenecarboxaldehyde condensation was electrochemically deposited on a gold (Au) electrode and used to remove metal ions found in rural waters. The structural analysis of Fc‐DPM was recorded by means of nuclear magnetic resonance (NMR) techniques. The Fc‐DPM was electrochemically coated on an indium tin oxide‐polyethylene terephthalate (ITO‐PET) surface, and the resulting Fc‐DPM/ITO‐PET was characterized using scanning electron microscopy (SEM)–energy dispersive X‐ray (EDX) analysis. The heavy metal and mineral content of four real water samples from the same rural area were determined by inductively coupled plasma mass spectrometry (ICP‐MS) before and after electrochemical removal. The proposed Fc‐DPM/Au electrode was successfully applied for aluminum ion (Al3+) and barium ion (Ba2+) removal for the first time, and the limit of detection (LOD) was calculated as 0.003 and 0.217 ppb for Ba2+ and Al3+, respectively. [ABSTRACT FROM AUTHOR]

Barium ferrite powder was produced using a standard ceramic procedure, and its structure and optical properties were investigated. X-ray diffraction analysis (XRD) showed that the powder had a w-type hexagonal structure. The crystallite size was at approximately 35–36 nm, with bulk density and lattice constants increasing as zinc concentration rose. Conversely, X-ray density and porosity decreased with the increasing zinc concentration. This material has useful optical properties, as well as the standard ferrimagnetic properties of barium ferrite, which make it suitable for use in recording media. Ferrimagnetic behavior, which is useful for recording media, occurs because the powder's crystallites have their unit cell axes aligned. Up to the near-infrared part of the spectrum, the powder was found to have a very low absorption coefficient. Both of these properties—an arrangement that gives rise to ferrimagnetism and a corresponding low optical density—make barium ferrite very attractive for high-density recording and microwave applications. Fourier transform infrared spectra of the samples were recorded in the wavenumber range of 400–4000 cm−1 and supported the X-ray diffraction findings by confirming the idea of the formation of W-type hexagonal ferrite by the presence of two prominent peaks at 454 and 591 cm−1 in the FTIR spectra. Zinc addition was also found to enhance the optical properties of the material. The UV–VIS analysis confirms that the band gap energy of Ba-Ni ferrite was indeed reduced by zinc doping. Values decrease from 3.34 eV to 3.20 eV for direct transitions and from 2.96 eV to 2.79 eV for indirect transitions, using Tauc equation. That means that zinc doping enhances the optical properties of Ba ferrite without affecting the hexagonal structure of Ba-Ni ferrite. Moreover, key parameters of optical performance such as the dielectric constant, the extinction coefficient, the penetration depth, and the refractive index show a dramatic increase with a rise in zinc concentration. These attributes make zinc-doped Ba-Ni ferrite a promising optoelectronic material. The material also showed high absorbance in the wavelengths ranging from 334 to 338 nm, which makes it good for the solar cell applications. Overall, zinc-doped Ba-Ni ferrite is a good candidate for sustainable and renewable energy applications. Our study of the optical properties of barium ferrite up to the near-infrared part of the spectrum demonstrated that the powdered material has a very low absorption coefficient. Indeed, the combination of ferrimagnetism and low optical density makes barium ferrite particularly appealing for use in high-density recording and microwave technology applications. [ABSTRACT FROM AUTHOR]

Herein, films of barium antimonides (BaSb) are fabricated by a thermal deposition technique under a vacuum pressure of 10−5 mbar. BaSb films exhibit orthorhombic lattice. Over a wide range of scans, the films are mostly stoichiometric, displaying atomic contents of 50.17 and 49.83 at% for Ba and Sb, respectively. Morphological analyses of these films show the growth of large grains with sizes ranging from 1.64 to 4.14 μm. Dynamic electrical measurements on Ag/BaSb/Ag films are conducted in the frequency domain of 0.01–1.80 GHz. The films display features of voltage‐controlled negative capacitance source (VCNC) and resonance–antiresonance peaks at a critical frequency of 1.64 GHz. Lorentz models spectral analyses on these peaks indicate that they correspond to a high‐frequency capacitance value of 2.8 nF, a density of oscillators of 4 × 1010 cm−3, and a scattering time constant of τ = 100 ns. Additionally, Ag/BaSb/Ag films show a wide variety in the cutoff frequency spectra, making them suitable for high‐frequency applications. The cutoff frequency varies from 2.6 GHz to 1.0 THz as driving frequency increases from 1.0 to 1.64 GHz. The features of VCNC sources, resonance–antiresonance behavior, and high cutoff frequency make BaSb thin films promising for thin‐film transistors and 6 G technology applications. [ABSTRACT FROM AUTHOR]

Understanding fish movement in river systems is essential in identifying habitats which are important for species to perpetuate. Water chemistry, paired with fish otoliths, can be used to trace movements among different habitats, although a detailed understanding of spatial variation in water chemistry is first required. To obtain this knowledge, we analysed surface water collected from 59 sites throughout the Clarence River Basin, a coastal river basin in northern New South Wales, Australia. The primary objective was to quantify the spatial variation of trace metals and strontium isotope ratios (87Sr:86Sr) for future and paired use with otolith microchemistry to track fish movement. Using ICP-OES, we identified that some trace metals, particularly strontium and barium as well as 87Sr:86Sr ratios, varied spatially when analysing all water samples and revealed three distinct regions centring around the estuary, interior and outer regions. These differences were driven by variation in the underlying surface geology between the Clarence–Moreton Basin and the New England Block. Tidal influence also affected trace metals and 87Sr:86Sr ratios throughout the estuarine area. We suggest that the level of differentiation identified in the current study has the potential to discriminate broad-scale fish movements among regions/habitats using otolith analysis, with fine scale movements best elucidated using complementary techniques. [ABSTRACT FROM AUTHOR]

We assessed the effects of soil type on the concentrations of seven elements (calcium, potassium, sulfur, phosphorus, iron, manganese, zinc) in plants using x‐ray fluorescence (XRF) analysis and plant specimens collected from calcareous and ultramafic soil areas, and ‘general soils’ (other types of soil represented by Brown Forest soils and Andosols) of Japan. Compared with the plants from other types of soils, the means of these seven elements were lower in plants originating from ultramafic soils, especially in phosphorus. Plants from calcareous soil areas had high iron and zinc concentrations on average, but this tendency was biased by plants collected on Mt. Fujiwara, which had extremely high average values of these elements. Calcium concentration in plants had a negative correlation with zinc or iron from calcareous or general soils, respectively, and iron showed positive correlations with zinc, manganese, and sulfur in plants from calcareous, ultramafic, and general soils, respectively. These correlations were not found in plants from general soils, suggesting that these relationships reflect the chemical characteristics of soil types. On the contrary, plants from all soil types showed a positive correlation between sulfur and phosphorus, whereas a positive correlation between potassium and phosphorus was found in plants from calcareous and general soils, but not in ultramafic plants, which instead showed a weak, but statistically significant correlation between potassium and sulfur. Statistically, iron and sulfur concentrations were positively correlated in all soil types, but manganese showed a low correlation with the other elements. [ABSTRACT FROM AUTHOR]

Reductive dissolution of barium (Ba) sulfate in wetland soils may increase Ba bioavailability in the environment, yet no information is available regarding Ba remediation using biochar. This study investigated the effectiveness of sugarcane (Saccharum officinarum) straw biochar pyrolyzed at 350 °C (BC350), 550 °C (BC550), and 750 °C (BC750) in inhibiting barite dissolution and, consequently, Ba availability in a soil artificially spiked with barite and flooded for 365 days. Increasing pyrolysis temperature alters the carbon structure, and increases dehydration and depolymerization, resulting in more stable biochar that releases less DOC (8.6-fold decrease from BC350 to BC750). Additionally, high-temperature biochar (BC750) had 1.7 times higher carbon (C) content, 2.4 times higher ash content, and a 13.1 times greater specific surface area (SSA) than low-temperature biochar (BC350). Amending soil with BC750 increased pH but did not promote reducing conditions, and thus did not promote barite dissolution. Conversely, greater DOC in low-temperature biochar, particularly BC350, favored reducing conditions and increased barite dissolution by 23%, with BC550 also showing an 18% increase. This enhancement led to a greater pool of Ba sorbed into more labile exchangeable sites. In summary, pyrolysis temperature affects biochar attributes, which in turn influences the soil geochemical environment and Ba speciation. Low-temperature biochar (BC350) shows potential as an amendment to increase the bioavailable Ba pool in assisted remediation programs, such as biochar-assisted phytoremediation. Highlights: • Biochar pyrolysis temperature affected both redox potential and barite dissolution. • BC750 mitigated barite dissolution while modifying exchangeable sorption sites. • DOC release from low temperature biochar promoted barite reductive dissolution. • BC350 may enhance biochar-mediated phytoremediation applications. [ABSTRACT FROM AUTHOR]

Heavy metal contamination especially in aqueous media has become an important risk to human health and environment. Therefore, due to the broad distribution of barium (Ba2+) and strontium (Sr2+) ions in the environment and wide variety of their harmful health effects for human, development of efficacious systems for their accurate and selective determination is of great importance. Aiming to develop a point-of-care and easy-to-use sensing device, a paper-based colorimetric sensing device was designed for simultaneous measurement of Ba2+ and Sr2+ ions standing on the basis of the color change of sodium rhodizonate (SR) in the presence of various concentrations of the target analytes. These color changes were photographed using a smartphone, and after analyzing with Photoshop 2022 software, the average variations in the intensities of colors (RGB (red, green, blue) model) were used to draw the calibration curves. The quantitative identification of Ba2+ and Sr2+ ions in a single solution was carried out by masking one of them at a moment. The average color intensities (G) displayed a linear relationship with the concentration of the analytes in the ranges of 5––300 ppm and 5–350 ppm with the limit of detection (LOD) values of 3.64 and 4.75 ppm for Ba2+ and Sr2+ ions, respectively. Moreover, the selectivity of the proposed analytical device was assessed; SR was selective for the target analytes versus the other ions causing a considerable color change. Furthermore, the practical application of this colorimetric device was investigated by the excellent performance in real samples indicating its potential for field applications. [ABSTRACT FROM AUTHOR]

A new three‐dimensional (3D) coordination polymer, namely, poly[diaqua[μ5‐2,2′‐(1,3,5,7‐tetraoxo‐1,2,3,5,6,7‐hexahydropyrrolo[3,4‐f]isoindole‐2,6‐diyl)diacetato]barium(II)], [Ba(C14H6N2O8)(H2O)2]n, (I), has been synthesized by the microwave‐irradiated reaction of Ba(NO3)2 with N,N′‐bis(glycinyl)pyromellitic diimide {BGPD, namely, 2,2′‐(1,3,5,7‐tetraoxo‐1,2,3,5,6,7‐hexahydropyrrolo[3,4‐f]isoindole‐2,6‐diyl)diacetatic acid, H2L}. The title compound was structurally characterized by single‐crystal X‐ray diffraction analysis and powder X‐ray diffraction analysis, as well as IR spectroscopy. In the crystal structure of (I), the BaII ion is nine‐coordinated by six carboxylate O atoms from five symmetry‐related L2− dianions and one imide O atom, as well as two water O atoms. The coordination geometry of the central BaII ion can be described as a spherical capped square antiprism. One carboxylate group of the ligand serves as a μ3‐bridge linking the BaII cations into a one‐dimensional polynuclear secondary building unit (SBU). Another carboxylate group of the ligand acts as a μ2‐bridge connecting the 1D SBUs, thereby forming a two‐dimensional (2D) SBU. The resulting 2D SBUs are extended into a 3D framework via the pyromellitic diimide moiety of the ligand as a spacer. The 3D Ba framework can be simplified as a 5‐connected hexagonal boron nitride net (bnn) topology. The intermolecular interactions in the 3D framework were further investigated by Hirshfeld surface analysis and the results show that the prominent interactions are H...O (45.1%), Ba...O (11.1%) and C...H (11.1%), as well as H...H (11.1%) contacts. The thermal stability, photoluminescence properties and UV–Vis absorption spectra of (I) were also investigated. The coordination polymer exhibits a fluorescence emission with a quantum yield of 0.071 and high thermal stability. [ABSTRACT FROM AUTHOR]

Leaf area varies within and between species, and previous work has linked this variation to environment and evolutionary history. However, many previous studies fail to examine both these factors and often are data‐limited.To address this, our study developed a new workflow using machine learning to automate the extraction of leaf area from herbarium collections of Australian eucalypts (Eucalyptus, Angophora and Corymbia). This dataset included 136,599 measurements, expanding existing data on this taxon's leaf area by roughly 50‐fold. Our methods were validated using field standard metrics of accuracy, and comparisons to manual measurements both from the present study and existing datasets.With this dataset for the eucalypt clade, we observed positive relationships between leaf area and mean annual temperature and precipitation similar to those reported for the global flora. However, these relationships were not consistently observed within species, potentially due to gene flow suppressing local adaptation. When we examined these relationships at different phylogenetic levels, the slope of trait–climate associations within lineages converged towards the overall eucalypt slope at shallow phylogenetic scales (5–12 MY), suggesting that effects of gene flow relax just above the species level.The strengthening of trait–climate correlations at evolutionary scales just beyond the intraspecific level may represent a widespread phenomenon across various traits and taxa. Future studies can unveil these relationships with the larger sample sizes of new trait datasets generated through machine learning.Synthesis. Using machine learning, researchers are able to confirm current positive global relationships between leaf area and mean annual temperature and precipitation. Additionally, they were able to take this a step further and examine how it changes across time. Here they saw that at roughly 5–12 million years ago in the phylogenetic tree, the trait–climate slope begins to show significantly less variation. Overall, the study shows the potential of machine learning in ecology, with exciting new potential findings with its use. [ABSTRACT FROM AUTHOR]

Objectives: Nitrogen isotopes (δ15N) are widely used to study human nursing and weaning ages. Conventional methods involve sampling 1‐mm thick sections of tooth dentine—producing an averaging effect that integrates months of formation. We introduce a novel protocol for measuring δ15N by multicollector secondary ion mass spectrometry (SIMS). Materials and Methods: We sampled dentine δ15N on a weekly to monthly basis along the developmental axis in two first molars of healthy children from Australia and New Zealand (n = 217 measurements). Nitrogen isotope ratios were determined from measurements of CN− secondary molecular ions in ~35 μm spots. By relating spot position to enamel formation, we identified prenatal dentine, as well as sampling ages over more than 3 years. We also created calcium‐normalized barium and strontium maps with laser ablation‐inductively coupled plasma‐mass spectrometry. Results: We found rapid postnatal δ15N increases of ~2‰–3‰, during which time the children were exclusively breastfed, followed by declines as the breastfeeding frequency decreased. After weaning, δ15N values remained stable for several months, coinciding with diets that did not include meat or cow's milk; values then varied by ~2‰ starting in the third year of life. Barium did not show an immediate postnatal increase, rising after a few months until ~1–1.5 years of age, and falling until or shortly after the cessation of suckling. Initial strontium trends varied but both individuals peaked months after weaning. Discussion: Developmentally informed SIMS measurements of δ15N minimize time averaging and can be precisely related to an individual's early dietary history. [ABSTRACT FROM AUTHOR]

Introduction: Current guidelines for double contrast barium esophagography studies (BAS) suggest that patients should be nil per os (NPO) prior to completing BAS for optimal esophageal coating, although the time required varies between practices and institutions. It is believed that consumption of food or water disrupts the ability for thick barium contrast to properly coat the esophageal mucosa. Exams that are rescheduled for this reason can lead to delays in care, without substantial evidence that NPO status truly affects esophageal mucosal coating for these exams with current barium mixtures. Objective: The study aims to identify the necessity, or lack thereof, of standard NPO protocol in patients undergoing BAS, in effort to prevent unnecessary procedural delay. Materials and methods: This study is an IRB-approved HIPAA-compliant study of 370 consecutive adult patients (115 male/255 female, mean age 55) who underwent BAS at our institution from January to June of 2022. Patients were divided into two groups: < 4 h NPO (n = 334), and ≥ 4 h NPO (n = 36). Four abdominal radiologists blinded to NPO interval independently reviewed a random sample of approximately 92 patients (91–94) and graded esophageal coating on a 4-point-scale with 1 being insufficient coating and 4 being optimal coating. Results: No significant statistical difference in mean esophageal coating score was found between the ≥ 4 h NPO cohort (3.04 ± SD 0.78) and the < 4 h NPO cohort (2.97 ± SD 0.70; P = 0.54). Subset analysis of patients who were NPO for < 2 h (n = 9) also showed no significant difference in mean esophageal coating score (3.11 ± SD 0.6; P = 0.92), compared to the standard ≥ 4 NPO status. Conclusion: Non-adherence to standard NPO protocol prior to BAS studies did not result in a significant difference in esophageal coating when compared to traditional preprocedural fasting of 4 or more hours. [ABSTRACT FROM AUTHOR]

Abstract. Using herbarium specimens spanning 133 years and field-collected measurements, we assessed intraspecific trait (leaf structural and stomatal) variability from grass species in the Great Plains of North America. We focused on two widespread, closely related grasses from the tribe Paniceae: Dichanthelium oligosanthes subsp. scribnerianum (C3) and Panicum virgatum (C4). Thirty-one specimens per taxon were sampled from local herbaria from the years 1887 to 2013 to assess trait responses across time to changes in atmospheric [CO2] and growing season precipitation and temperature. In 2021 and 2022, the species were measured from eight grasslands sites to explore how traits vary spatially across natural continental precipitation and temperature gradients. Δ13C increased with atmospheric [CO2] for D. oligosanthes but decreased for P. virgatum , likely linked to increases in precipitation in the study region over the past century. Notably, this is the first record of decreasing Δ13C over time for a C4 species illustrating 13C linkages to climate. As atmospheric [CO2] increased, C:N increased and δ15N decreased for both species and %N decreased for D. oligosanthes. Across a large precipitation gradient, D. oligosanthes leaf traits were more responsive to changes in precipitation than those of P. virgatum. In contrast, only two traits of P. virgatum responded to increases in temperature across a gradient: specific leaf area (increase) and leaf dry matter content (decrease). The only shared significant trend between species was increased C:N with precipitation. Our work demonstrates that these closely related grass species with different photosynthetic pathways exhibited various trait responses across temporal and spatial scales, illustrating the key role of scale of inquiry for forecasting leaf trait responses to future environmental change. [ABSTRACT FROM AUTHOR]

This study investigates the presence of potentially toxic elements (PTEs) in lettuce (Lactuca sativa L.) grown in urban gardens in a highly industrialized city in Brazil and evaluates the effectiveness of different washing methods in reducing contamination. Ten elements (arsenic (As), barium (Ba), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), vanadium (V), and zinc (Zn)) were analyzed for their concentration, and a health risk assessment was performed. The results showed that Pb concentrations in lettuce from gardens near the Capuava Petrochemical Complex reached 0.77 mg kg−1, exceeding both national and international safety limits. The most effective washing procedure involved the use of sodium hypochlorite, which reduced As by 46%, Pb by 48%, and V by 52%. However, elements such as Ba, Cd, Cr, and Ni showed limited reductions of less than 10% across all washing methods. Health risk assessments revealed a particular concern for children, with the total cancer risk (TCR) exceeding acceptable limits in some gardens. Isotopic analysis of Pb revealed that atmospheric pollution from gasoline emissions and industrial activities were the primary sources of contamination. The elevated levels of Pb, Cr, and As highlight the need for targeted health education in local communities, especially regarding the importance of proper washing techniques. Risk management strategies, including improved contamination control and public awareness, are crucial to minimize exposure to these harmful elements, particularly in vulnerable populations like children. [ABSTRACT FROM AUTHOR]

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Electronic waste (e-waste) has been identified as an emerging pollutant and is the fastest growing waste stream at the present time. Significant technological development and modernization within the last decade has led to the rapid accumulation of outdated, broken and unwanted electrical and electronic equipment (EEE). Electronic products mainly consist of a range of metal containing components that, when disposed of improperly, could result in metal constituents leached into the environment and posing a health risk to humans and animals alike. Metal exposure can induce oxidative stress in organisms, which could lead to synergistic, antagonistic and additive effects. The metals found highest in abundance in the simulated e-waste leachate, were nickel (Ni), barium (Ba), zinc (Zn), lithium (Li), iron (Fe), aluminium (Al) and copper (Cu). An acute exposure study was conducted over a 96 h period to determine the potential toxicity of e-waste on the test organism Danio rerio. Biomarker analysis results to assess the biochemical and physiological effects induced by e-waste leachate, showed a statistically significant effect induced on acetylcholinesterase activity, superoxide dismutase, catalase activity, reduced glutathione content, glutathione s-transferase, malondialdehyde and glucose energy available. The Integrated Biomarker Response (IBRv2) analysis revealed a greater biomarker response induced as the exposure concentration of e-waste leachate increased. [ABSTRACT FROM AUTHOR]

Ceramic proton conductors have the potential to lower the operating temperature of solid oxide cells (SOCs) to the intermediate temperature range of 400–600 °C. This is attributed to their superior ionic conductivity compared to oxide ion conductors under these conditions. However, prominent proton-conducting materials, such as yttrium-doped barium cerates and zirconates with specified compositions like BaCe1−xYxO3−δ (BCY), BaZr1−xYxO3−δ (BZY), and Ba(Ce,Zr)1−yYyO3−δ (BCZY), face significant challenges in achieving dense electrolyte membranes. It is suggested that the incorporation of transition and alkali metal oxides as sintering additives can induce liquid phase sintering (LPS), offering an efficient method to facilitate the densification of these proton-conducting ceramics. However, current research underscores that incorporating these sintering additives may lead to adverse secondary effects on the ionic transport properties of these materials since the concentration and mobility of protonic defects in a perovskite are highly sensitive to symmetry change. Such a drop in ionic conductivity, specifically proton transference, can adversely affect the overall performance of cells. The extent of variation in the proton conductivity of the perovskite BCZY depends on the type and concentration of the sintering aid, the nature of the sintering aid precursors used, the incorporation technique, and the sintering profile. This review provides a synopsis of various potential sintering techniques, explores the influence of diverse sintering additives, and evaluates their effects on the densification, ionic transport, and electrochemical properties of BCZY. We also report the performance of most of these combinations in an actual test environment (fuel cell or electrolysis mode) and comparison with BCZY. [ABSTRACT FROM AUTHOR]

A barium-rich Celestine (Sr,Ba)SO4 concentrate from the primary Mexican ore production was used as a thickening agent to produce closed-cell Zn-22Al-2Cu alloy foams, while calcium carbonate was used as a foaming agent. The microstructure and mechanical properties of the foams were analyzed by optical microscopy, scanning electron microscopy, and compression tests, respectively. The Zn-22Al-2Cu alloy foams showed a typical lamellar eutectic microstructure, constituted by a zinc-rich phase (η) and a (α) solid solution that was richer in aluminum, while a copper-rich (ε) phase was formed in the interdendritic regions. The SEM micrographs show the presence of small particles and aggregates that are randomly scattered in the cell walls and correspond to unreacted calcite and Celestine–Barian particles, especially for the higher barite addition. The compressive curves showed smooth behavior, wherein the particles at the cell walls did not affect the foam's compressive behavior. The trial containing 1.5 wt. % of BaSO4 and 1.0 wt. % of CaCO3 showed a higher energy absorption capacity of 5.64 MJ m−3 because of its highest relative density and lowest porosity values. The Celestine–Barian concentrate could be used as a foaming agent for high melt-point metals or alloys based on the TGA results. [ABSTRACT FROM AUTHOR]

Background Purpose Dysphagia is one of the most common complaints that gastroenterologists encounter in the outpatient setting. To evaluate this common complaint, patients are often sent for a barium esophagram, a test that is widely available, inexpensive, and easy to perform. This simple test provides a reliable method to evaluate esophageal anatomy and structural abnormalities.This narrative reviews the history of the development and validation of the timed‐barium esophagram (TBE), along with its strengths and limitations, and discusses its use in the pre‐ and posttreatment assessment of patients with achalasia, esophagogastric junction outflow obstruction (EGJOO), and esophageal strictures. Providing excellent anatomic detail of the esophagus and an accurate assessment of esophageal emptying, over time, the TBE has become part of the standard workup in our Swallowing Center for patients with dysphagia. [ABSTRACT FROM AUTHOR]

Context. Neutron-capture elements represent an important nucleosynthetic channel in the study of the Galactic chemical evolution of stellar populations. For stellar populations behind significant extinction, such as those in the Galactic centre and along the Galactic plane, abundance analyses based on near-infrared (NIR) spectra are necessary. Previously, spectral lines from the neutron-capture elements, such as copper (Cu), cerium (Ce), neodymium (Nd), and ytterbium (Yb), have been identified in the H band, while yttrium (Y) lines have been identified in the K band. Aims. Due to the scarcity of spectral lines from neutron-capture elements in the NIR, the addition of useful spectral lines from other neutron-capture elements is highly desirable. The aim of this work is to identify and characterise a spectral line suitable for abundance determination from the most commonly used s-process element, namely barium. Methods. We observed the NIR spectra of 37 M giants in the solar neighbourhood at high spectral resolution and with a high signal-to-noise ratio using the IGRINS spectrometer on the GEMINI South telescope. The full H- and K-bands were recorded simultaneously at R = 45 000. Using a manual spectral synthesis method, we determined the fundamental stellar parameters for these stars and derived the barium abundance from the Ba line (6s5d 3D2 → 6s6p 3P2o) at λair = 23 253.56 Å in the K band. Results. We demonstrate that the Ba line in the K band at 2.33 μm (λ23 253.56) is useful for abundance analyses from the spectra of M giants. The line becomes progressively weaker at higher temperatures and is only useful in M giants and the coolest K giants at supersolar metallicities. Conclusions. We can now add Ba to the trends of the heavy elements Cu, Zn, Y, Ce, Nd, and Yb, which can be retrieved from high-resolution H- and K-band spectra. This opens up the study of nucleosynthetic channels, including the s-process and the r-process, in dust-obscured populations. Thus, these elements can be studied for heavily dust-obscured regions of the Galaxy, such as the Galactic centre. [ABSTRACT FROM AUTHOR]

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Alginate microcapsules are the most frequently used materials for cell transplantation. Different crosslinkers affect crosslinking affinity, which has a significant influence on microcapsule properties. The objective was to prepare in vitro microcapsules using calcium, barium, iron, manganese, nickel, and strontium as divalent cations to observe their potential for use in cell transplantation. Sodium alginate was added dropwise to the individually prepared crosslinkers to observe diffusion-based gelling. Alginate microcapsules were investigated regarding capsule stability, physiological properties, and cell viability. After 30 days of incubation, cell viability was greater than 90% for the cell-encapsulated microcapsules when crosslinked with CaCl2 and NiCl2. Viability decreased in the following order: CaCl2>NiCl2>BaCl2>SrCl2>MnCl2>FeCl2. A compression test was performed to investigate the required force to deform 30% of microcapsules, and only MnCl2, FeCl2 (180mM), and NiCl2 (50mM) demonstrated higher resistance to the applied force than CaCl2. Except for the FeCl2 group, all cell-encapsulated microcapsules remained intact for 45 days. Potential sensitivities to CaCl2 during cell transplantation may compel alternative crosslinker usage, and our study revealed that NiCl2 and BaCl2 can be used as alternative crosslinkers to CaCl2 due to their high cell viability and consistent stability. [ABSTRACT FROM AUTHOR]

Tunable dielectric materials, serving as key components in microwave electronic application, require both high dielectric tunability and low dielectric loss. However, the trade-off between dielectric tunability and dielectric loss restricts the improvement of the overall dielectric tunability properties. In the present study, we proposed an effective approach to benefit both high tunability and low dielectric loss, i.e., improving intrinsic dielectric response from the lattice polarization and restricting the extrinsic dielectric response from the domain motions at the same time. Experimentally different acceptor dopants were employed, including the introduction of K at the A-site and Mn, Fe and Co at the B-site. On one hand, the different acceptor dopants could adjust the Curie temperature and consequently resulting in the enhanced intrinsic dielectric response at room temperature. On the other hand, the employment of acceptor dopant could introduce the oxygen vacancies and form the acceptor-oxygen vacancy dipoles which may restrict the reorientation of microdomains, resulting in the decrease of extrinsic dielectric response. Herein, both enhanced tunability and reduced dielectric loss were achieved in acceptor doped BZT ceramics at ambient temperature (27 °C). In particular, Fe doped BZT ceramics achieved both high dielectric tunability of 93.8 % and low dielectric loss of 0.0038. Such performance is competitive with that of previous reported dielectric tunable materials. In addition, the dielectric tunability of Fe doped BZT ceramics maintained over 60 % within the wide temperature range from −20 °C to 60 °C. [ABSTRACT FROM AUTHOR]

Green hydrogen (H2) production from solar water splitting necessitates photoelectrodes with superior photoelectrochemical (PEC) activity and durability. However, surface defects and photocorrosion instability—especially at high potentials—limit PEC performance and stability. Herein, the prototypical bismuth vanadate (BiVO4) photoanode is used to demonstrate a holistic approach to improve photocurrent density and long‐term stability. In this approach, high surface‐area nanostructuring of BiVO4 is combined with barium (Ba) doping with semi‐crystalline hafnium oxide (HfO2) surface passivation and single‐atom nickel platinum (NiPt) catalysts. The introduction of Ba2+ ions into BiVO4 increases the concentration of conductive V4+ ions or the ratio of V4+ ions to oxygen vacancies, avoiding V5+ dissolution during water oxidation. The semi‐crystalline HfO2, which serves as a passivation layer, prevents BiVO4 photocorrosion by suppressing harmful chemical reactions when holes are transferred to the electrolyte. The synergistic use of isolated single‐atom and Ni‐Pt coordination improves charge transfer at the photoanode/electrolyte interface, leading to enhanced PEC kinetics and stability. As a result, a photoelectrode is demonstrated with ≈6.5 mA cm−2 at 1.23 V versus a reversible hydrogen electrode (RHE) and continuous operation for 800 h with a negligible degradation rate. This work provides a promising approach to improve photoanodes for PEC H2 production. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Methods Results Conclusion The primary objective of this study was to assess the efficacy and safety of in‐office transnasal oesophagoscopy (TNO) and balloon dilatation for patients presenting with symptoms of high dysphagia. The secondary objective was to conduct a subgroup analysis to better understand patient selection.Retrospective observational study from a single university hospital.Two‐hundred four TNO and balloon dilatations were performed for 146 patients (median age 73 years; range 12–94 years). Indications included cricopharyngeal hypertrophy ± pouch (n = 70), hypopharyngeal/upper oesophageal web/stenosis (n = 18), head and neck cancer treatment‐related (n = 41), multi‐level obstruction (n = 13) and symptom‐based (n = 4). The mean EAT‐10 score improved from 21.2 (SD ± 8.92) pre‐dilatation to 12.6 (SD ± 10.7) post‐dilatation overall (median follow‐up 4.4 months; range 1.5 months–6.21 years). Cricopharyngeal hypertrophy and/or web without dysmotility cohort responded the best with the mean EAT‐10 score improvement from 20.4 (SD ± 8.21) to 4.4 (SD ± 6.71). Head and neck cancer patient group showed three types of responses: good response although effect transient requiring repeat dilatations; initial good response however stops responding over time and no response. The overall complication rate was 0.98% (n = 2/204; both failed in‐clinic attempts) with 0% perforation rate.TNO and balloon dilatation is a safe and effective treatment modality for managing high dysphagia in patients with identifiable non‐malignant obstructive pathologies at and around the level of the upper oesophageal sphincter, including head and neck cancer treatment‐related patients, both short‐term and long‐term. Barium swallow is an excellent screening tool for assessing the swallow as a whole. [ABSTRACT FROM AUTHOR]

Energy storage capacitors for advanced pulse power systems and high-power electric devices is a kind of important electronic components, the demand continues to grow, specifications are constantly being upgraded, and performance boundaries are continuously being pushed. Multilayer ceramic capacitors (MLCCs) for energy storage applications have received increasing attention due to the advantages of ultralow equivalent series inductance, equivalent series resistance, good frequency characteristics, strong voltage overload ability, and stable operability at high temperatures. However, the relatively low energy storage density significantly limits its broader applications. Here, 0.4Ba 0.55 Sr 0.45 TiO 3 -0.4Bi 0.5 Na 0.5 TiO 3 -0.2SrZrO 3 (0.4BST-0.4BNT-0.2SZ) relaxor ferroelectric MLCCs are prepared at different heating rates. Excellent recoverable energy storage density of 10.3 J cm−3 and high energy efficiency of 93 % are achieved in fast-fired MLCCs under the electric field of 106.3 V μm−1. The impedance spectroscopy and thermally stimulated depolarization current technologies are employed to investigate the conductance mechanism of MLCCs, and the results can explain the effect of heating rate on the performance of MLCCs. In addition, the charge-discharge performances of fast-fired MLCCs are also thoroughly investigated, exhibiting great thermal and fatigue stability. [ABSTRACT FROM AUTHOR]

Despite the pivotal role of stannum doping in achieving ultrahigh piezoelectric performance in barium titanate-based ceramics, the fundamental mechanisms underlying this enhancement remain elusive. Here, we introduce a single variable nonstoichiometric stannum strategy in lead-free barium titanate-based ceramics with giant piezoelectricity, revealing that stannum doping contributes intrinsically and extrinsically to enhance piezoelectricity. Density functional theory calculations elucidate the intrinsic enhancement of polarization arising from lattice distortion and increased space for titanium-oxygen bonds induced by optimal stannum doping, which is corroborated by Rayleigh analysis. A phase transition from ferroelectric multiphase coexistence to paraelectric phase is observed, alongside a rapid miniaturized and eventually disappeared domains with increasing stannum doping. This evolution in phase structure and domain configuration induces a nearly vanishing polarization anisotropy and low domain wall energy, facilitating easy polarization rotation and domain wall motion, thereby significantly contributing to the extrinsic piezoelectric response. Consequently, the origins of ultrahigh performance can be attributed to the synergistic effect of stannum-induced intrinsic and extrinsic contributions in barium titanate-based ceramics. This study provides fundamental insights into the role of doping elements and offers guidance for the design of high-performance piezoelectrics. The mechanisms of the enhancement of stannum doping in achieving high piezoelectric performance in barium titanate-based ferroelectric ceramics remain elusive. Here, the authors introduce a single variable nonstoichiometric stannum strategy to reveal the intrinsic and extrinsic contributions for enhancing piezoelectricity after stannum doping. [ABSTRACT FROM AUTHOR]

Introduction: There are limited data available regarding the connection between heavy metal exposure and mortality among hypertension patients. Aim: We intend to establish an interpretable machine learning (ML) model with high efficiency and robustness that monitors mortality based on heavy metal exposure among hypertension patients. Methods: Our datasets were obtained from the US National Health and Nutrition Examination Survey (NHANES, 2013–2018). We developed 5 ML models for mortality prediction among hypertension patients by heavy metal exposure, and tested them by 10 discrimination characteristics. Further, we chose the optimally performing model after parameter adjustment by genetic algorithm (GA) for prediction. Finally, in order to visualize the model's ability to make decisions, we used SHapley Additive exPlanation (SHAP) and Local Interpretable Model-Agnostic Explanations (LIME) algorithm to illustrate the features. The study included 2347 participants in total. Results: A best-performing eXtreme Gradient Boosting (XGB) with GA for mortality prediction among hypertension patients by 13 heavy metals was selected (AUC 0.959; 95% CI 0.953–0.965; accuracy 96.8%). According to sum of SHAP values, cadmium (0.094), cobalt (2.048), lead (1.12), tungsten (0.129) in urine, and lead (2.026), mercury (1.703) in blood positively influenced the model, while barium (− 0.001), molybdenum (− 2.066), antimony (− 0.398), tin (− 0.498), thallium (− 2.297) in urine, and selenium (− 0.842), manganese (− 1.193) in blood negatively influenced the model. Conclusions: Hypertension patients' mortality associated with heavy metal exposure was predicted by an efficient, robust, and interpretable GA-XGB model with SHAP and LIME. Cadmium, cobalt, lead, tungsten in urine, and mercury in blood are positively correlated with mortality, while barium, molybdenum, antimony, tin, thallium in urine, and lead, selenium, manganese in blood is negatively correlated with mortality. [ABSTRACT FROM AUTHOR]

Hypokalemic paralysis is a clinical syndrome characterized by acute flaccid paralysis with concomitant hypokalemia. Complications, such as acute respiratory failure and cardiac arrhythmias, can be fatal. If treated appropriately, the patient can recover without any sequelae. We present a rare case of life-threatening hypokalemic paralysis following the ingestion of an unknown substance. At presentation, her serum potassium concentration was 1.9 mmol/L. A review of the patient's history confirmed the ingestion of barium chloride. She was diagnosed with acute barium poisoning characterized by high serum and urine barium levels. Aggressive potassium repletion was administered intravenously and orally. Her serum potassium concentration dropped to 1.5 mmol/L and peaked at 5.4 mmol/L following treatment. The patient achieved a complete recovery and was discharged without sequelae. Barium can competitively block the potassium inward rectifier channels and interfere with the efflux of intracellular potassium, leading to severe hypokalemia. Our report illustrates a rare presentation of acute barium intoxication and a differential diagnosis indicating hypokalemic paralysis. We also discuss the pathophysiological features and compare the clinical findings with cases of rebound hyperkalemia. [ABSTRACT FROM AUTHOR]

Simple Summary: Understanding how plants respond to increasing atmospheric CO2 is crucial for predicting future climate interactions. However, the long-term effects of rising CO2 on plant physiology, especially in tropical regions, are not well known. To investigate this, we studied how a CO2 increase of about 95 ppm from 1927 to 2015 affected five tropical tree species in Fiji. We analysed historical leaf samples to measure the following two key traits: how efficiently the trees use water (intrinsic water-use efficiency) and the maximum rate of conductance through leaf pores (maximum stomatal conductance). Our results showed that the responses to rising CO2 varied significantly by species. Generally, the number of stomata on the leaves was more important than their size in determining the trees' response to higher CO2 levels. While photosynthesis is a major factor in improving the water-use efficiency, changes in stomatal conductance primarily drive this trend across different species. Trees that showed greater increases in the water-use efficiency also displayed a greater reduction in stomatal conductance. Overall, our study shows the importance of considering differences in the maximum stomatal conductance when predicting how different tree species will react to increasing CO2 levels. Understanding plant physiological response to a rising atmospheric CO2 concentration (ca) is key in predicting Earth system plant–climate feedbacks; however, the effects of long-term rising ca on plant gas-exchange characteristics in the tropics are largely unknown. Studying this long-term trend using herbarium records is challenging due to specimen trait variation. We assessed the impact of a ca rise of ~95 ppm (1927–2015) on the intrinsic water-use efficiency (iWUE) and maximum stomatal conductance (gsmax) of five tropical tree species in Fiji using the isotopic composition and stomatal traits of herbarium leaves. Empirical results were compared with simulated values using models that uniquely incorporated the variation in the empirical gsmax responses and species-specific parameterisation. The magnitude of the empirical iWUE and gsmax response was species-specific, ranging from strong to negligible. Stomatal density was more influential than the pore size in determining the gsmax response to ca. While our simulation results indicated that photosynthesis is the main factor contributing to the iWUE gain, stomata were driving the iWUE trend across the tree species. Generally, a stronger increase in the iWUE was accompanied by a stronger decline in stomatal response. This study demonstrates that the incorporation of variation in the gsmax in simulations is necessary for assessing an individual species' iWUE response to changing ca. [ABSTRACT FROM AUTHOR]

Many plant species are known to take up metals from the soil and accumulate them to potentially toxic levels. This may provide tolerance to soils with high metal content or a defensive mechanism against herbivores and pathogens. Accumulators, plants that uptake and store elevated concentrations of metals, can be used in phytoremediation as a means to remove metals from contaminated soils. In this study, the native weed Conyza canadensis was grown in soils contaminated with elevated levels of lead (Pb), barium (Ba), zinc (Zn), copper (Cu), or chromium (Cr). All metals, except for Cr, were accumulated by the plants. Zinc and Cu, both essential elements, accumulated to the highest levels, while Pb and Ba were present at lower levels. All treatments except Cr showed accelerating rates of accumulation over the eight-week experiment. Barium, Cu, and Cr reduced aboveground biomass of the plants, indicating toxicity or a cost to metal accumulation. Lead and Zn promoted early flowering, while plants accumulating Ba, Cr, and Cu flowered in lower numbers. Overall, C. canadensis has promise in the phytoremediation of Pb, Cu, and Zn. [ABSTRACT FROM AUTHOR]

Background/Aims: Achalasia is a rare esophageal motility disease, for which peroral endoscopic myotomy (POEM) has emerged as a promising treatment option; however, recurrence remains a challenge. Timed barium esophagography (TBE) is a useful diagnostic tool and potential outcome predictor of achalasia. This study aimed to determine predictive tools for recurrence after POEM. Methods: This retrospective study enrolled achalasia patients who underwent POEM between January 2015 and December 2021. Patients were categorized into two groups using the 1-month post-POEM Eckardt scores and TBE: the discordant group (Eckardt score improved >50%, TBE decreased <50%) and the concordant group (both Eckardt score and TBE improved >50%). Recurrence was defined as a reincrease in the Eckardt score to more than three during follow-up. Results: Complete medical records were available in 30 patients who underwent POEM. Seventeen patients (56.7%) were classified into the discordant group, while 13 patients (43.3%) were in the concordant group. The overall recurrence rate was 11.9% at 1-year, increasing to 23.8% during the extended follow-up. The discordant group had a 6.87 fold higher recurrence rate than the concordant group (52.9% vs. 7.7%, p=0.017). Conclusions: These results strongly suggest that combining the Eckardt score with TBE can effectively predict recurrent achalasia after POEM. Patients in the discordant group had an elevated risk. [ABSTRACT FROM AUTHOR]

In the structure of the title salt, {[Ba(μ3-C3H2N3O2)2(μ-H2O)(H2O)]·H2O}n, the barium ion and all three oxygen atoms of the water molecules reside on a mirror plane. The hydrogen atoms of the bridging water and the solvate water molecules are arranged across a mirror plane whereas all atoms of the monodentate aqua ligand are situated on this mirror plane. The distorted ninefold coordination of the Ba ions is completed with four nitroso-, two carbonyl- and three aqua-O atoms at the distances of 2.763 (3)–2.961 (4) Å and it is best described as tricapped trigonal prism. The three-dimensional framework structure is formed by face-sharing of the trigonal prisms, via μ-nitroso- and μ-aqua-O atoms, and also by the bridging coordination of the anions via carbonyl-O atoms occupying two out of the three cap positions. The solvate water molecules populate the crystal channels and facilitate a set of four directional hydrogen bonds. The principal Ba–carbamoylcyanonitrosomethanido linkage reveals a rare example of the inherently polar binodal six- and three-coordinated bipartite topology (three-letter notation sit). It suggests that small resonance-stabilized cyanonitroso anions can be utilized as bridging ligands for the supramolecular synthesis of MOF solids. Such an outcome may be anticipated for a broader range of hard Lewis acidic alkaline earth metal ions, which perfectly match the coordination preferences of highly nucleophilic nitroso-O atoms. Thermal analysis reveals two-stage dehydration of the title compound (383 and 473 K) followed by decomposition with release of CO2, HCN and H2O at 558 K. [ABSTRACT FROM AUTHOR]

Ba[(Ca0.2Mg0.2Zn0.2Co0.2Ni0.2)1/3Nb2/3]O3 and Ba[(Mg0.25Zn0.25Co0.25Ni0.25)1/3Nb2/3]O3 perovskite single‐phase ceramics were synthesized by a solid‐state reaction method, and they were annealed at different temperatures in order to investigate the effect of B′‐site configurational entropy on phase stability, ordered domain structure and microwave dielectric characteristics. By comparing the B′‐site high‐entropy composition with B′‐site medium‐entropy and low‐entropy compositions, the entropy‐dominated phase‐stabilization effect and sluggish diffusion effect were observed in Ba[(Ca0.2Mg0.2Zn0.2Co0.2Ni0.2)1/3Nb2/3]O3. These effects enhanced the temperature stability of the B‐site 1:2 ordered structure. Ba[(Ca0.2Mg0.2Zn0.2Co0.2Ni0.2)1/3Nb2/3]O3 even reached a higher Qf value after annealing above the order‐disorder transition temperature (To‐d). This research extends the entropy regulation to ordered complex perovskite and provides a promising way to modify the performances of complex perovskite dielectric ceramics. [ABSTRACT FROM AUTHOR]

In this study, we report the modulation of the emission color and optical temperature‐sensing properties of Er3+ in Ba5Zn4Y8O21 crystals. Er3+ single‐doped Ba5Zn4Y8O21 phosphors showed green emission under 980 nm excitation. When codoping with Yb3+ ions, the red emission component from the Er3+ ions increased significantly, and the sample emission turned orange. Yb3+–Er3+ codoped Ba5Zn4Y8O21 samples exhibited bright red emission with a maximum IR/IG value of 89.30 when excited with a longer wavelength, 1550 nm. A broad range of emission colors could be modulated by adjusting the dopant concentration. The possible modulation mechanisms and upconversion processes were analyzed based on the luminescence decay curves and power‐dependent emission intensities. Furthermore, the optical temperature‐sensing properties of Ba5Zn4Y8O21:Er3+ and Ba5Zn4Y8O21:Er3+, Yb3+ phosphors with thermal coupled energy levels (TCELs) and nonthermal coupled energy levels (N‐TCELs) of Er3+ ions were investigated using fluorescence intensity ratio technique. Based on the TCELs (2H11/2/4S3/2), the Er3+ single‐doped and Yb3+–Er3+ codoped Ba5Zn4Y8O21 phosphors present the similar optical thermometry behaviors under 980 and 1550 nm excitation. The highest absolute (Sa) and relative sensitivity (Sr) are 3.95 × 10−3 K−1 at 573 K and 1.31% K−1 at 303 K, respectively. Based on N‐TCELs (4F9/2/2H11/2), the temperature‐sensing performance depends on the Yb3+ dopant and excitation wavelength. The highest values for Sa and Sr reached 5.46 K−1 at 303 K and 1.38% K−1 at 573 K for the Ba5Zn4Y8O21:Er3+, Yb3+ phosphor under 1550 nm excitation, respectively. In addition, the present phosphor exhibited high stability and repeatability over a wide temperature range. These results indicate that the multicolor modulation upconversion Ba5Zn4Y8O21‐based phosphor can be considered a potential reusable optical thermometer for noncontact temperature detection. [ABSTRACT FROM AUTHOR]

The B‐site cation ordering‐disordering transition process of complex perovskite Ba(B′1/3B″2/3)O3‐based microwave ceramics can be directly promoted by accelerating the mass transport process rather than depending on long‐time annealing treatment. Clear evidences suggest that CuO doping is helpful in enhancing the densification process of Ba(Co0.7Zn0.3)1/3Nb2/3O3 (BCZN) ceramics and promoting the growth and coarsening of the ordering domain, facilitated by the formation of quasi‐liquid CuO‐xCu2O layers. The improvement of the 1:2 ordering degree is attributed to the accelerated mass transport process enabled by quasi‐liquid CuO‐xCu2O layers rather than long‐time annealing treatment. Consequently, the Q×f values experience a significant increase from 21,200 to 69,300 GHz, owing to enhancements in the relative density and 1:2 ordering degree. CuO‐doped BCZN ceramics achieve high 1:2 ordering degree and Q×f values at relatively low temperatures and for short periods of time, and more importantly, it circumvents conventional lengthy annealing processes (>30 h) effectively to promote its ordering transition. These findings underscore the potential of accelerating mass transport process to promote ordering‐disordering phase transitions and improving dielectric properties of complex perovskite Ba(B′1/3B″2/3)O3‐based microwave ceramics. [ABSTRACT FROM AUTHOR]

• A coupled electromagnetic-mechanical model is built to calculate the coupling behaviors of superconducting coils. • Mechanical deformation impacts the motion of magnetic flux and changes the critical current of superconductors. • The roles of contact conditions in the superconducting coils are derived theoretically. • A mechanical homogenization model is proposed to simplify the model containing hundreds of contact pairs. Rare-earth based barium copper oxide (REBCO) superconducting coated conductors are promising candidates for the design of high field magnets. In a high magnetic field, these conductors have to withstand huge Lorentz force, which would threaten the safety of superconducting devices. Recently, researchers have found that the electromagnetic-mechanical coupling has a significant impact on the overall response of the magnet system. It has been demonstrated that mechanical deformation can lead to the movement of magnetic flux in superconductors and changes in the critical current of superconductors. To take into account the electromagnetic-mechanical coupling effects, REBCO coated conductors are modeled as deformable conductors based on continuum mechanics of electromagnetic solids. Then, a fully coupled electromagnetic-mechanical model is developed in this paper, which is verified with the experimental results. Furthermore, during the electromagnetic-mechanical coupling simulation, contact separation occurs in REBCO pancake coils. To characterize the global mechanical performance of the REBCO pancake coils (containing hundreds of contact conditions), the concept of flexural rigidity in elastic shell theory is employed. Then, a mechanical homogeneous model is proposed to simplify the model containing hundreds of contact pairs and enable the effective simulation of large-scale HTS systems. This framework can provide theoretical support to the mechanical research of high field magnets. [ABSTRACT FROM AUTHOR]

BaAl 2 Si 2 O 8 (barium feldspar-based) materials are widely used in glass and ceramic industry due to high melting temperature, chemical resistance, low thermal expansion, low dielectric constants and attractive luminescence properties. The durability of barium feldspar ceramics strongly depends on reversible phase transitions between the low-temperature modification (celsian), and series of high-temperature (HT) polymorphs known as 'hexacelsian'. Numerous works have been devoted to the study of the thermal transitions of 'hexacelsian' by X-ray powder diffraction methods and transmission electron microscopy, the use of which provides limited information about structural changes. Here, the crystal structures, thermal properties and phase transitions of HT BaAl 2 Si 2 O 8 polymorphs are characterized for the first time using in-situ HT X-ray single-crystal structural study (SCXRD), and micro-Raman spectroscopy up to 1000 °C. The crystal structure of α-hexacelsian under ambient conditions is monoclinic (I 2/ a). The alpha-form undergoes two polymorphic transformations upon heating: into an orthorhombic (Fmmm) β-modification above 300 °C and into a hexagonal (P –62 m) γ-modification above 700 °C. These transitions lead to significant changes in the unit-cell volume: an obstacle in the production of BaAl 2 Si 2 O 8 -based ceramics. [ABSTRACT FROM AUTHOR]

High-entropy ceramics have garnered significant attention in recent years owing to their exceptional properties and structural diversity. In this work, single-phase medium/high entropy ceramics, namely (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.5 Ti 0.5)O 3 and (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.1 Ti 0.9)O 3 , were successfully designed and prepared utilizing Spark Plasma Sintering (SPS). A comprehensive investigation was conducted into the phase structure, microscopic morphology, dielectric properties, and thermal behavior of these ceramics. It was observed that all ceramics maintained a cubic perovskite structure (space group: Pm 3 ‾ m), and the introduction of multi-element doping rendered them more stable across a wide frequency and temperature range. Notably, (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.5 Ti 0.5)O 3 exhibited remarkably low dielectric loss (0.0001 at 1 kHz) at room temperature, along with excellent dielectric temperature stability (25–400 °C). By reducing the zirconium concentration in (Ca 0.2 Sr 0.4 Ba 0.4)(Zr 0.1 Ti 0.9)O 3 , a slight decrease in dielectric temperature stability was observed (25–350 °C); however, it demonstrated lower thermal conductivity (0.41 W/(m·K), 1200 °C) and maintained good high-temperature stability. The discovery highlights the promising practicality of both ceramics for high-temperature dielectric applications. [ABSTRACT FROM AUTHOR]

The synergistic piezoelectric and osteoconductive properties of barium titanate (BT) and hydroxyapatite (HA) could stir the development of a new generation of synthetic bone graft substitutes, with capability for rapid and safe osseointegration. The research focused on two concurrent approaches for coupling the BT and HA materials: (i) conventional sintering of BT-HA powder mixtures; and (ii) functionalization of pre-sintered BT with HA coatings using magnetron sputtering (MS). Irrespective of the BT/HA ratios ranging from 95/5 to 80/20 wt%, nanocrystalline or highly-crystallized nature of the powders, sub-micron- or micron-sized particle dimensions, and sintering temperature, it was observed that the BT-HA reactivity cannot be prevented above 800 °C. At higher temperatures in the range of 1000–1300 °C, HA undergoes decomposition and extensively reacts with BT, leading to the formation of several secondary phases such as CaTiO 3, Ba 2 Ca(PO 4) 2 , BaCa 6 (PO 4) 4 O, BaCa(PO 3) 4 , and β -Ca 2 P 2 O 7. As a consequence, the cytocompatibility assessed in fibroblast and osteoblast cell cultures, as well as the piezoelectric response, were significantly altered. Applying HA coatings by MS to the sintered BT ceramics successfully preserved their piezoelectric properties, while also providing an unaltered cytocompatible and osteogenic-prone surface. The HA coatings were fully crystallized at post-deposition annealing temperatures of 550 and 700 °C, achieving crystalline qualities comparable to HA powders sintered at 1100 and 1200 °C, respectively. No reactivity events between BT and HA were observed. Partial reactivity was only noticeable upon annealing at 1000 °C. Therefore, it is suggested that the HA coating of BT is effective in seamlessly coupling the piezoelectric and osteogenic properties of the two constituents without compromise. • BT-HA powder mixtures inevitably react at high-temperature to form secondary phases. • The HA osteogenic component can be lost at sintering temperatures above 1000 °C. • The secondary phases lead to a decay of the piezoelectric and biological responses. • HA-magnetron sputtered BT – a feasible solution to overcome inter-phases reactivity. • HA-coated BT yields uncompromised piezoelectric and in-vitro biologic performances. [ABSTRACT FROM AUTHOR]