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Volatile element abundances vary substantially among terrestrial planetary bodies like Earth, Mars, Moon, and differentiated asteroids, leading to intense debate about the governing processes. howardites-eucrites-diogenites (HED) meteorites, most likely from asteroid 4-Vesta, represent highly volatile-depleted Solar System samples, offering critical insights into these processes. Zinc is a moderately volatile element and its isotopic composition reveals sources of volatiles in planetary bodies. Our study finds Zn isotopic anomalies in diogenites overlapping with noncarbonaceous reservoirs, indicating negligible contributions of outer solar system materials to 4-Vesta's volatiles. Besides, zinc isotopic composition of 4-Vesta is lighter than that of chondrites, contrary to the expected signature of evaporation-based volatile depletion. This suggests that after 4-Vesta lost all its volatiles through evaporation during the magma ocean stage, partial kinetic recondensation occurred that produced the observed isotopically light composition. These insights, combined with previous data, underscore the process of global evaporation followed by partial condensation as a key factor influencing the final volatile budget of planetary bodies.
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Hydrogen boride (HB) nanosheets are expected to be safe and lightweight hydrogen carriers because of their high gravimetric hydrogen density (8.5 wt %) and photon-driven hydrogen release under mild conditions. However, previously reported HB nanosheets respond only to ultraviolet (UV) light to release hydrogen. In this study, we develop dye-modified HB nanosheets that can release hydrogen under visible light irradiation (>470 nm) without heat input. Hydrogen generation is initiated by electron injection from excited dye molecules into the conduction band of the HB nanosheets. The conduction band of the HB nanosheets is formed by the antibonding states of the B 2py and H 1s atomic orbitals, and the electrons injected from the dye molecules react with the protons of the HB nanosheets to release gaseous hydrogen molecules. Although the hydrogen production is terminated after long-term light irradiation owing to dye oxidation and/or loss of protons in HB nanosheets, the total amount of the released hydrogen molecules corresponds to approximately 25% of the protons in HB nanosheets even under the extra mild conditions. The addition of a sacrificial agent like iodine ions and a proton source like formic acid sustained the H2 generation from the dye-modified HB nanosheets under visible light irradiation for long term.
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The 2018 heart allocation system has significantly influenced heart transplantation and left ventricular assist device (LVAD) utilization. Our study aims to investigate age-related outcomes following LVAD implantation in the post-allocation era. Using the National Inpatient Sample, we analyzed data from 7375 patients who underwent LVAD implantation between 2019 and 2020. The primary endpoint was in-hospital mortality following LVAD implantation, stratified by age categories. The age groups were 18-49, 50-59, 60-69, and over 70. These represented 26%, 26%, 31%, and 17% of patients, respectively. Patients aged 60-69 and those over 70 exhibited higher in-hospital mortality rates of 12% and 17%, respectively, compared to younger age groups (7% for 18-49 and 6% for 50-59). The age groups 60-69 and over 70 were independent predictors of mortality, with adjusted odds ratios of 1.99 (p = 0.02; 95% confidence interval [CI], 1.12-3.57) and 2.88 (p = 0.002; 95% CI, 1.45-5.71), respectively. Additionally, a higher Charlson Comorbidity Index was associated with increased in-hospital mortality risk (adjusted odds ratio 1.39; p = 0.02; 95% CI, 1.05-1.84). Additionally, patients above 70 experienced a statistically shorter length of stay. Nonhome discharge was found to be significantly high across all age categories. However, the difference in hospitalization cost was not statistically significant across the age groups. Our study highlights that patients aged 60 and above face an increased risk of in-hospital mortality following LVAD implantation in the post-allocation era. This study sheds light on age-related outcomes and emphasizes the importance of considering age in LVAD patient selection and management strategies.
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The immune-stromal cell interactions play a key role in health and diseases. In periodontitis, the most prevalent infectious disease in humans, immune cells accumulate in the oral mucosa and promote bone destruction by inducing receptor activator of nuclear factor-κB ligand (RANKL) expression in osteogenic cells such as osteoblasts and periodontal ligament cells. However, the detailed mechanism underlying immune-bone cell interactions in periodontitis is not fully understood. Here, we performed single-cell RNA-sequencing analysis on mouse periodontal lesions and showed that neutrophil-osteogenic cell crosstalk is involved in periodontitis-induced bone loss. The periodontal lesions displayed marked infiltration of neutrophils, and in silico analyses suggested that the neutrophils interacted with osteogenic cells through cytokine production. Among the cytokines expressed in the periodontal neutrophils, oncostatin M (OSM) potently induced RANKL expression in the primary osteoblasts, and deletion of the OSM receptor in osteogenic cells significantly ameliorated periodontitis-induced bone loss. Epigenomic data analyses identified the OSM-regulated RANKL enhancer region in osteogenic cells, and mice lacking this enhancer showed decreased periodontal bone loss while maintaining physiological bone metabolism. These findings shed light on the role of neutrophils in bone regulation during bacterial infection, highlighting the novel mechanism underlying osteoimmune crosstalk.
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Pérdida de Hueso Alveolar , Periodontitis , Humanos , Ratones , Animales , Neutrófilos/metabolismo , Neutrófilos/patología , Citocinas , Pérdida de Hueso Alveolar/microbiología , Osteogénesis , Ligando RANKRESUMEN
Solid-state hydrogen storage materials are safe and lightweight hydrogen carriers. Among the various solid-state hydrogen carriers, hydrogen boride (HB) sheets possess a high gravimetric hydrogen capacity (8.5 wt%). However, heating at high temperatures and/or strong ultraviolet illumination is required to release hydrogen (H2) from HB sheets. In this study, the electrochemical H2 release from HB sheets using a dispersion system in an organic solvent without other proton sources is investigated. H2 molecules are released from the HB sheets under the application of a cathodic potential. The Faradaic efficiency for H2 release from HB sheets reached >90%, and the onset potential for H2 release is -0.445 V versus Ag/Ag+, which is more positive than those from other proton sources, such as water or formic acid, under the same electrochemical conditions. The total electrochemically released H2 in a long-time experiment reached ≈100% of the hydrogen capacity of HB sheets. The H2 release from HB sheets is driven by a small bias; thus, they can be applied as safe and lightweight hydrogen carriers with economical hydrogen release properties.
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Here, we report that a mesoporous silica nanoparticle (MSN) coated with a fluoresceine-labeled bovine serum albumin (F-BSA) hydrogel layer works as a temperature-responsive nanocarrier for tetrakis-N-methylpyridyl porphyrin (TMPyP) and as a fluorescence ratiometric pH probe. F-BSA hydrogel-coated MSN containing TMPyP (F-BSA/MSN/TMPyP) was synthesized by thermal gelation of denatured F-BSA on the external surface of MSN. The F-BSA hydrogel layer was composed of an inner hard corona layer and an outer soft layer and was stable under physiological conditions. F-BSA/MSN/TMPyP exhibited temperature-dependent exponential release of TMPyP. In this release profile, the MSN was found to be a suitable host for stable encapsulation of tetracationic TMPyP by electrostatic interactions, and the F-BSA hydrogel layer mediated the diffusion of TMPyP from the MSN pore interior into the solution phase. Increasing temperature promoted partitioning of TMPyP from the pore interior to the F-BSA hydrogel layer, from where it was spontaneously released into the bulk solution phase by cation exchange. F-BSA/MSN/TMPyP also gave a linear ratiometric fluorescence response (1.3 per pH unit) in the pH range from 6.1 to 8.9.
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Nanopartículas , Porfirinas , Dióxido de Silicio , Fluorescencia , Hidrogeles , Albúmina Sérica Bovina , Concentración de Iones de Hidrógeno , CationesRESUMEN
Mechanical stimuli serve as crucial regulators of bone mass, promoting bone formation. However, the molecular mechanisms governing how mesenchymal stem cells (MSCs) respond to mechanical cues during their differentiation into osteogenic cells remain elusive. In this study, we found that cyclic stretching enhances MSC proliferation but does not increase the expression of osteoblast-related genes. We further revealed that this proliferative effect is mediated by fibroblast growth factor 2 (FGF-2), synthesized by MSCs in response to mechanical stress. Cell proliferation induced by cyclic stretching was inhibited upon the addition of either U0126, an inhibitor of mitogen-activated protein kinase kinase (MEK), or early growth response 1 (EGR1)-targeting small-hairpin RNA (shRNA), indicating the involvement of the extracellular signal-regulated kinase (ERK)/EGR1 signaling pathway. Osteoblast differentiation, evaluated through ALP activity, osteoblast-related gene expression, and mineralization, was stimulated by recombinant human FGF-2 (rhFGF-2) when applied during the proliferation phase, but not when applied during the differentiation stage alone. Our results suggest that FGF-2 indirectly promotes osteoblast differentiation as a downstream effect of stimulating cell proliferation. For the first time, we demonstrate that cyclic stretching induces MSCs to produce FGF-2, which in turn encourages cell proliferation through an autocrine/paracrine mechanism, consequently leading to osteoblast differentiation.
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Células Madre Mesenquimatosas , Osteogénesis , Humanos , Factor 2 de Crecimiento de Fibroblastos/farmacología , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Estrés Mecánico , Diferenciación Celular , Proliferación Celular , Osteoblastos/metabolismoRESUMEN
Most of previous photocatalysts contain metal species, thus exploring a metal-free photocatalyst is still challenging. A metal-free photocatalyst has an advantage for the development of economical and non-toxic artificial photosynthesis system and/or environmental purification applications. In this study, rhombohedral boron monosulfide (r-BS) was synthesized by a high-pressure solid-state reaction, and its photocatalytic properties were investigated. r-BS absorbed visible light, and its photocurrent action spectrum also exhibited visible light responsivity. The r-BS evolved hydrogen (H2) from water under ultraviolet (UV) as well as under visible light irradiation, and its internal quantum efficiency reached 1.8% under UV light irradiation. In addition to the H2 evolution reaction, the r-BS photocatalyst drove carbon dioxide (CO2) reduction and dye oxidation reactions under UV irradiation. Although bare r-BS was not so stable under strong light irradiation in water, cocatalyst modification improved its stability. These results indicate that r-BS is a new class of non-metal photocatalyst applicable for H2 production, CO2 reduction, and environmental purification reactions.
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Conventional hydrogen production, as an alternative energy resource, has relied on fossil fuels to produce hydrogen, releasing CO2 into the atmosphere. Hydrogen production via the dry forming of methane (DRM) process is a lucrative solution to utilize greenhouse gases, such as carbon dioxide and methane, by using them as raw materials in the DRM process. However, there are a few DRM processing issues, with one being the need to operate at a high temperature to gain high conversion of hydrogen, which is energy intensive. In this study, bagasse ash, which contains a high percentage of silicon dioxide, was designed and modified for catalytic support. Modification of silicon dioxide from bagasse ash was utilized as a waste material, and the performance of bagasse ash-derived catalysts interacting with light irradiation and reducing the amount of energy used in the DRM process was explored. The results showed that the performance of 3%Ni/SiO2 bagasse ash WI was higher than that of 3%Ni/SiO2 commercial SiO2 in terms of the hydrogen product yield, with hydrogen generation initiated in the reaction at 300 °C. Using the same synthesis method, the current results suggested that bagasse ash-derived catalysts had better performance than commercial SiO2-derived catalysts when exposed to an Hg-Xe lamp. This indicated that silicon dioxide from bagasse ash as a catalyst support could help improve the hydrogen yield while lowering the temperature in the DRM reaction, resulting in less energy consumption in hydrogen production.
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A copper-zirconia composite having an evenly distributed lamellar texture, Cu#ZrO2, was synthesized by promoting nanophase separation of the Cu51Zr14 alloy precursor in a mixture of carbon monoxide (CO) and oxygen (O2). High-resolution electron microscopy revealed that the material consists of interchangeable Cu and t-ZrO2 phases with an average thickness of 5 nm. Cu#ZrO2 exhibited enhanced selectivity toward the generation of formic acid (HCOOH) by electrochemical reduction of carbon dioxide (CO2) in aqueous media at a Faradaic efficiency of 83.5% at -0.9 V versus the reversible hydrogen electrode. In situ Raman spectroscopy has revealed that a bifunctional interplay between the Zr4+ sites and the Cu boundary leads to amended reaction selectivity along with a large number of catalytic sites.
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An unexplored tin oxide crystal phase (Sn3 O4 ) was experimentally synthesized via a facile hydrothermal method. After tuning the often-neglected parameters for the hydrothermal synthesis, namely the degree of filling of the precursor solution and the gas composition in the reactor head space, an unreported X-ray diffraction pattern was discovered. Through various characterization studies, such as Rietveld analysis, energy dispersive X-ray spectroscopy, and first-principles calculations, this novel material was characterized as orthorhombic mixed-valence tin oxide with the composition SnII 2 SnIV O4 . This orthorhombic tin oxide is a new polymorph of Sn3 O4 , which differs from the reported conventional monoclinic structure. Computational and experimental analyses showed that orthorhombic Sn3 O4 has a smaller band gap (2.0â eV), enabling greater absorption of visible light. This study is expected to improve the accuracy of hydrothermal synthesis and aid the discovery of new oxide materials.
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The titanium dioxide (TiO2 ) photocatalyst is only active under UV irradiation due to its wide-gap nature. A novel excitation pathway denoted as interfacial charge transfer (IFCT) has been reported to activate copper(II) oxide nanoclusters-loaded TiO2 powder (Cu(II)/TiO2 ) under visible-light irradiation for only organic decomposition (downhill reaction) so far. Here, the photoelectrochemical study shows that the Cu(II)/TiO2 electrode exhibits a cathodic photoresponse under visible-light and UV irradiation. It originates from H2 evolution on the Cu(II)/TiO2 electrode, while O2 evolution takes place on the anodic side. Based on the concept of IFCT, a direct excitation of electrons from the valence band of TiO2 to Cu(II) clusters initiates the reaction. This is the first demonstration of a direct interfacial excitation-induced cathodic photoresponse for water splitting without any addition of a sacrificial agent. This study is expected to contribute to the development of abundant visible-light-active photocathode materials for fuel production (uphill reaction).
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We herein propose a simple and sensitive electrochemical flow biosensor platform without an external flow device. The sensing unit comprises a platinum nanohole array electrode deposited on a nanoporous track-etched membrane (PtNH/NPM), a packed-layer of glucose oxidase-encapsulated mesoporous silica particles (GOD/MPS), and bovine serum albumin hydrogel film (BSA gel film). This sensing unit was fixed at the open window at the side of the plastic container with internal solution containing NaCl as osmotic reagent. When the sample glucose solution (0.10 mL) was pipetted at the sensing unit, a portion of the sample solution (5 µL) was spontaneously transferred into the BSA gel film. The concentration gradient of NaCl between the internal solution and the BSA gel film induced osmotic flow of water toward the internal solution. This osmotic flow assisted delivery of glucose to the GOD/MPS and enzymatically generated H2O2 to the PtNH/NPM. The proposed sensor could be used repeatedly and produced a linear current response for glucose, with a limit of detection of 16 µM. These sensor performances confirmed availability of the sensor design utilizing the osmotic flow.
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Técnicas Biosensibles , Dióxido de Silicio , Peróxido de Hidrógeno , Cloruro de Sodio , Electrodos , Glucosa Oxidasa , Enzimas Inmovilizadas , GlucosaRESUMEN
The trade-off relationship between narrowing the bandgap and achieving sufficient redox potentials accounts for the hindrance to the development of an efficient photocatalyst. Most of the previous researchers attempt to narrow the bandgap of semiconductors by impurity doping to achieve visible-light sensitivity, but this approach causes the losses of their oxidation and/or reduction ability. Conversely, this study presents a bandgap widening strategy by doping to improve the redox potential of photogenerated carriers. Employing first-principles simulations, we propose the lanthanum-doped bismuth vanadate (La-BiVO4) photocatalyst as a wider-bandgap semiconductor exhibiting stronger oxidation ability compared to pristine BiVO4, and the results revealed that the bismuth orbital in the valence band (VB) was diluted by lanthanum-ion doping, while the VB shifted to a higher potential (positively shifted). Thereafter, a La-BiVO4 powder was synthesized via a solid-state reaction, after which its activity was evaluated in the photocatalytic oxidation of 2-propanol (IPA). La-BiVO4 exhibited bandgap widening; thus, the number of absorbed photons under visible-light irradiation was lower than that of pristine BiVO4. However, the quantum efficiency (QE) of La-BiVO4 for the oxidation of IPA was higher than that of the pristine BiVO4. Consequently, the photocatalytic reaction rate of La-BiVO4 was superior to that of pristine BiVO4 under the same visible-light irradiation conditions. Although the bandgap of La-BiVO4 is widened, it is still sensitive to the cyan-light region, which is the strongest in the sunlight spectrum. These results demonstrate that the orbital dilution strategy by impurity elemental doping is effective for bandgap widening and contributes to improving the oxidation and/or reduction ability of the photogenerated charge carriers. This study elucidates the possibility of boosting photocatalytic performances via bandgap widening.
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We report a method to synthesize dolomite [CaMg(CO3)2] from amorphous calcium magnesium carbonate (ACMC) via solid-state transformation. When ACMC is heated in air, it does not crystallize into dolomite but decomposes into Mg calcite, magnesium oxide, and CO2. Hence, we heated ACMC in a closed system filled with CO2 gas (pCO2 >1.2 bar at 420 °C) and produced submicron-sized dolomite. Single-phase dolomite was obtained after dissolving impurities in the run products, such as northupite [Na3Mg(CO3)2Cl] and eitelite [Na2Mg(CO3)2], in water. Also, we investigated the crystallization process of dolomite by changing the heating temperature and heating time. Despite crystallization by solid-state transformation, the heated samples crystallized to dolomite via Ca-rich protodolomite with no ordering reflection of X-ray diffraction as previously observed for hydrothermal synthesis. The results demonstrated that this crystallization pathway is kinetically favored even in solid-state transformation and that the Ca-rich protodolomite phase preferentially crystallizes during heating, leading to phase separation from the amorphous phase. Therefore, the crystallization process via protodolomite as a precursor is a common mechanism in dolomite crystallization, suggesting the presence of kinetic barriers other than hydration of cations.
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Sample return missions have provided the basis for understanding the thermochemical evolution of the Moon. Mare basalt sources are likely to have originated from partial melting of lunar magma ocean cumulates after solidification from an initially molten state. Some of the Apollo mare basalts show evidence for the presence in their source of a late-stage radiogenic heat-producing incompatible element-rich layer, known for its enrichment in potassium, rare-earth elements, and phosphorus (KREEP). Here we show the most depleted lunar meteorite, Asuka-881757, and associated mare basalts, represent ancient (~3.9 Ga) partial melts of KREEP-free Fe-rich mantle. Petrological modeling demonstrates that these basalts were generated at lower temperatures and shallower depths than typical Apollo mare basalts. Calculated mantle potential temperatures of these rocks suggest a relatively cooler mantle source and lower surface heat flow than those associated with later-erupted mare basalts, suggesting a fundamental shift in melting regime in the Moon from ~3.9 to ~3.3 Ga.
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Meteoroides , Luna , Animales , Femenino , Caballos , Silicatos , EstroRESUMEN
Coronary anatomy is key for arterial switch operations as reimplantation for coronary artery patterns originating from the same sinus is often challenging. We experienced an extremely rare coronary artery anatomy case (Leiden convention: 1 R, 1LCx) and successfully performed an arterial switch operation with coronary button extension and neo-pulmonary trunk realignment maneuver.
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Operación de Switch Arterial , Anomalías de los Vasos Coronarios , Transposición de los Grandes Vasos , Humanos , Transposición de los Grandes Vasos/cirugía , Corazón , Arteria Pulmonar/diagnóstico por imagen , Arteria Pulmonar/cirugía , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/cirugía , Vasos Coronarios/anatomía & histología , Anomalías de los Vasos Coronarios/diagnóstico por imagen , Anomalías de los Vasos Coronarios/cirugíaRESUMEN
The condensation of globular myoglobin (Mb) at the pore entrances of mesoporous silica (MPS) with a series of pore diameters (4.2, 6.4, 7.7, and 9.0 nm) was examined by differential scanning calorimetry (DSC) and contrast-matching small-angle neutron scattering (CM-SANS) experiments. The DSC measurements were performed to estimate the amount of Mb adsorbed at two different adsorption sites, namely, the pore interior and the pore entrance regions. The CM-SANS measurements were conducted to observe condensation of Mb molecules at the pore entrance regions. Notably, the nanopore entrance with a diameter close to twice that of the Mb diameter was found to be the specific cavity to facilitate the condensation of globular Mb. The Mb condensation occurred at the entrances of the 6.4 nm pore during the adsorption uptake from concentrated Mb solutions, whereas the adsorption uptake from diluted Mb solutions induced the condensation of Mb at the entrances of the 7.7 nm pore.