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The chemical conversion of CO2into value-added products is the key technology to realize a carbon-neutral society. One representative example of such conversion is the reverse water–gas shift reaction, which produces CO from CO2. However, the activity is insufficient at ambient pressure and lower temperatures (<600 °C), making it a highly energy-intensive and impractical process. Herein, we report indium oxide nanofibers modified with palladium catalysts that exhibit significantly potent redox activities toward the reduction of CO2splitting via chemical looping. In particular, we uncover that the doped palladium cations are selectively reduced and precipitated onto the host oxide surface as metallic nanoparticles. These catalytic gems formed operando make In2O3lattice oxygen more redox-active in H2and CO2environments. As a result, the composite nanofiber catalysts demonstrate the reverse water–gas shift reaction via chemical looping at record-low temperatures (≤350 °C), while also imparting high activities (CO2conversion: 45%). Altogether, our findings expand the viability of CO2splitting at lower temperatures and provide design principles for indium oxide-based catalysts for CO2conversion.

Hexagonal perovskite-related oxides have been of significant interest in recent years for their potential applications in electrochemical devices, particularly as solid electrolytes in fuel cells and electrolysis cells. The anisotropy of proton migration in these materials has been playing a critical role in their performance, but the underlying mechanisms and factors governing this anisotropy remain poorly understood. In this study, using the {0001}-plane preferentially oriented Ba5Er2Al2ZrO13(BEAZ) hexagonal perovskite electrolyte-supported cell as a model system, we reveal the anisotropic characteristics of the proton conduction behavior. By controlling the orientation of the grains in the BEAZ thin film via the surface energy-driven secondary grain growth phenomenon, we demonstrate that proton migration in BEAZ is more favorable in the lateral direction than in the vertical direction. More importantly, density functional theory calculations and ab initio molecular dynamics simulations suggest that anisotropic proton migration in the lateral direction is preferred through the perovskite-like layer rather than the intrinsically oxygen-deficient layer. Our study demonstrates that an electrostatic neutral perovskite-like layer in hexagonal perovskite-related oxides should not be overlooked as a key parameter for achieving higher proton conduction kinetics.

Using direct radiologic image inputs, two large language models, GPT-4V and Gemini Pro Vision, improved in diagnostic accuracy with increasing temperature settings; although GPT-4V slightly underperformed compared with radiologists, it nonetheless demonstrated promising potential as a supportive tool in diagnostic decision-making.

A kinetic model describing the integral stereoselectivity of lipase, which refers to selectivities for all positions of triacylglycerol, diacylglycerol, and monoacylglycerol isomers, was developed. Based on the Ping-Pong Bi–Bi mechanism, the model incorporates a stepwise hydrolysis reaction from triacylglycerol to glycerol with non-enzymatic acyl migration of diacylglycerol and monoacylglycerol isomers. With the kinetic model, lipase-catalysed hydrolysis of trioleoylglycerol (TOG) was investigated using lipases from the porcine pancreas, Chromobacterium viscosum, and Pseudomonas fluorescensin a reverse micelle system. By varying the initial substrate concentration, the model was able to provide a good description of stepwise TOG hydrolysis by each lipase, with the lipases exhibiting different selectivity. With the kinetic constants derived from the model, the stereoselective nature of lipases can be estimated comprehensively and quantitatively while considering the entire process of lipase-catalysed TOG hydrolysis. Therefore, the proposed approach will provide valuable information for the effective selection, screening, and development of lipases, particularly the production of lipids with regioisomerically or enantiomerically specific structures.

Climate change engendered by carbon emissions has become a major threat to human life and the world economy. Many of early studies corroborate that carbon tax and subsidy are effective policy tools to alleviate climate change. Most of them, however, use closed-economy models with a single firm to analyze effects of these two policies. This paper explores effects of carbon tax, subsidy and foreign carbon emissions on economic activities in an open macroeconomic model that features low- and high-carbon firms. The main findings suggest that carbon tax, subsidy and foreign carbon emissions all deliver heterogeneous outcomes by largely affecting high-carbon firms. The shortage of national income due to weak economic activities leads the economy to issue more international bonds. The takeaway from all analyses is that government should introduce various carbon taxes that are geared towards target firms with different carbon emissions and adopt optimal means to manage national debt.

Immune checkpoint inhibitors (ICIs) have become an effective therapeutic option for colorectal cancer and studies on these drugs have therefore increased greatly. Efficacy assessments of ICIs in preclinical orthotopic colorectal cancer using MRI have not been reported however due to the difficulties in conducting colorectal imaging. The purpose of this present study was to investigate the feasibility of using magnetic resonance colonography (MRC) to evaluate the efficacy of an ICI, an anti-PD-L1 antibody, in an orthotopic colorectal cancer mouse model. The mouse model was generated by the engraftment of colorectal cancer cells into the submucosal layer of the colon. Anti-cancer efficacy was assessed by tumor volume and metastatic tumor number analyses, and these values were significantly lower in the PD-L1 antibody-treated group compared to the controls. Histological analyses using H&E and Ki-67 immunohistochemical staining confirmed a highly efficacious tumor growth inhibition and enhanced infiltration by CD4+ and CD8+ lymphocytes in the PD-L1 antibody-treated group. We conclude that MRC has the potential to be used for ICI efficacy assessments against orthotopic colorectal cancer mouse model.

Highly active metal nanoparticles are desired to serve in high-temperature electrocatalysis, for example, in solid oxide electrochemical cells. Unfortunately, the low thermal stability of nanosized particles and the sophisticated interface requirement for electrode structures to support concurrent ionic and electronic transport make it hard to identify the exact catalytic role of nanoparticles embedded within complex electrode architectures. Here we present an accurate analysis of the reactivity of oxide electrodes boosted by metal nanoparticles, where all particles participate in the reaction. Monodisperse particles (Pt, Pd, Au and Co), 10 nm in size and stable at high temperature (more than 600 °C), are uniformly distributed onto mixed-conducting oxide electrodes as a model electrochemical cell via self-assembled nanopatterning. We identify how the metal catalysts activate hydrogen electrooxidation on the ceria-based electrode surface and quantify how rapidly the reaction rate increases with proper choice of metal. These results suggest an ideal electrode design for high-temperature electrochemical applications.

Several reports on obesity have targeted to determine inhibitors of pancreatic lipase (EC 3.1.1.3, PL), which plays a major role in the digestion of dietary lipids, from natural sources. This study aimed to suggest soybean leaf, a soybean by-product, as a novel source of PL inhibitors and investigate PL inhibitory characteristics of the active constituents. Fluorometric lipase assay revealed that the soybean leaf extract has inhibitory activity against PL. UPLC-MS/MS analysis identified flavonoids (genistein, daidzein, formononetin, taxifolin, diosmetin, and glycitein) as active constituents. Among them, diosmetin and glycitein were novel PL inhibitors with half-maximal inhibitory concentrations of 131.9 ± 8.4 and 127.5 ± 7.4 μM, respectively. The inhibition mode of diosmetin and glycitein were deteremined as competitive type from the enzyme kinetic study, supported by molecular docking simulation. Their bindings to PL were confirmed to follow the static quenching process in fluorescence analysis. Collectively, the results of present study indicates soybean leaf and its flavonoids as a promising natural source for antiobesity functional food.

A main advantage of solid oxide fuel cells (SOFCs) operating at a high temperature (>650°C) is the flexibility of the fuel they use, specifically as they offer the possibility to utilize methane (natural gas). Unfortunately, however, the state-of-the-art SOFC anodes, composed of a nickel and an anionically conducting oxide such as yttria-stabilized zirconia (YSZ), are associated with Ni-catalyzed carbon deposition and the ensuing degradation of the anode performance. Here, we address these issues through the application of a simple, scalable, cost-effective ceramic coating method known as cathodic electrochemical deposition (CELD). Samaria-doped CeO2(SDC) was chosen as the coating material due to its high chemical stability against carbon formation, high electronic and ionic conductivities, and favorable electrocatalytic activity toward fuel oxidation reaction. Nanostructured SDC layers with a high specific surface area were successfully coated onto Ni surfaces via CELD. The physical and chemical attributes of each coating were characterized by a range of analysis tools, in this case SEM, TEM, XRD, EDS, ICP-MS and Raman spectroscopy. An analysis of the AC impedance spectroscopy (ACIS) of Ni-patterned YSZ symmetric cells (anode|electrolyte|anode) with SDC coatings revealed significantly enhanced electrode activity toward fuel oxidation and coking stability under dry or wet methane fuel at 650°C. These results suggest that the Ni-surface modification via CELD can be a feasible solution for the direct use of hydrocarbon fuels in SOFCs.

Direct utilization of methane fuels in solid oxide fuel cells (SOFCs) is a key technology to realize the immediate inclusion of such high-efficiency fuel cells into the current electricity generation infrastructure. However, the broad commercialization of direct-methane fueled SOFCs is critically hindered by the inadequate electrode activity and their poor longevity, which primarily stems from the carbon build-up issues. To make the technology more competitive, a novel electrode structure that can dramatically improve the tolerance against coking is essential. Herein, we present highly active and robust core–shell nanofiber anodes, La0.75Sr0.25Cr0.5Mn0.5O3@Sm0.2Ce0.8O1.9(LSCM@SDC), directly obtained with a single-nozzle electrospinning process through the use of two immiscible polymers. The intimate coverage of SDC on LSCM not only increases the active reaction sites but also promotes resistance toward carbon deposition and thermal aggregation. As such, the electrode polarization resistance obtained with LSCM@SDC NFs is among the lowest value ever reported with LSCM derivatives (∼0.11 Ω cm2in wet H2at 800 °C). The facile fabrication process of such complex heterostructures developed in this work is attractive for the design of not only SOFC electrodes but also other solid-state devices such as electrolysis cells, membrane reformers, and protonic cells.

AbstractBerberine, an isoquinoline alkaloid found in Coptidis Rhizoma(goldenthread) extract, has multiple pharmacological effects such as anti‐inflammatory, antimicrobial and anti‐ischemic effects. In the present study, we examined the effects of berberine on neuronal survival and differentiation in a hippocampal precursor cell line and in the memory deficient rat model. Berberine increased in a dose dependent manner the survival of hippocampal precursor cells as well as differentiated cells. In addition, berberine promoted neuronal differentiation of hippocampal precursor cells. In the memory deficient rat model induced by stereotaxic injection of ibotenic acid into entorhinal cortex (Ibo model), hippocampal cells were increased about 2.7 fold in the pyramidal layer of CA1 region and about 2 fold in the dentate gyrus by administration of berberine after 2 weeks of ibotenic acid injection. Furthermore, neuronal cells immunoreactive to calbindin were increased in the hippocampus and entorhinal cortex area by administration of berberine. Taken together, these results suggest that berberine has neuroprotective effect in the Ibo model rat brain by promoting the neuronal survival and differentiation.

Stereoselectivity, a distinctive characteristic of lipase (EC 3.1.1.3), refers to the ability to differentiate between enantiomeric positions (sn-1 and sn-3) in triacylglycerol (TAG). This property has been determined based on the time course of enantiomeric excess of diacylglycerol (DAG) considering several consecutive steps of lipase-catalyzed hydrolysis of TAG; however, this concept is insufficient to represent the true nature of lipases which are capable of hydrolyzing the sn-2 position of TAG under the condition acyl migration occurs. Here, we suggest “integral stereoselectivity” to capture the preference of lipases for all ester groups of both TAG and DAG, as a novel index of the stereochemistry of lipase. To determine integral stereoselectivity, we established an analytical system based on the chromatographic resolution of dioleoylglycerol (DO) enantiomers and regioisomers. DO enantiomers were derivatized with 4-nitrophenyl isocyanate, and subsequently, resolved by chiral-phase high-performance liquid chromatography–ultraviolet. Regioisomers of monooleoylglycerol and DO were analyzed by HPLC with an evaporative light-scattering detector. Time-course analysis of three model lipases involved in the hydrolysis of trioleoylglycerol validated the analytical system designed to determine the integral stereoselectivity. As an accurate indicator of lipase stereochemistry reflecting all hydrolysis steps, integral stereoselectivity can expedite the development of lipases with unique stereochemistry from agricultural sources and their application to the food industry.

The effects of reaction conditions on the spectrophotometric and fluorometric assays using alternative substrates (p-nitrophenyl palmitate and 4-methylumbelliferyl oleate) were investigated to optimize them for the high-throughput screening of lipase activity from agricultural products. Four model lipases from Chromobacterium viscosum, Pseudomonas fluorescens, Sus scrofa pancreas, and wheat germ (Triticum aestivum) were allowed to hydrolyze the alternative substrates at different substrate concentrations (1–5 mM), operating pH (5.0–8.0), and operating temperatures (25–55°C). The results show that both the spectrophotometric and fluorometric assays worked well at the standard reaction conditions (pH 7.0 and 30°C) for finding a typical lipase, although pH conditions should be considered to detect the catalytic activity of lipases, which are applicable to more acidic or alkaline pH circumstances. To validate the optimized conditions, the high-throughput screening of lipase activity was conducted using 17 domestic agricultural products. A pileus of Pleurotus eryngii showed the highest activity in both the spectrophotometric (633.42 μU/mg) and fluorometric (101.77 μU/mg) assays. The results of this research provide practical information for the high-throughput screening of lipases using alternative substrates on microplates.