Nitrogen Doping-Roused Synergistic Active Sites in Perovskite Enabling Highly Selective CO2 Photoreduction into CH4

The intricate protonation process in carbon dioxide reduction usually makes the product unpredictable. Thus, it is significant to control the reactive intermediates to manipulate the reaction steps. Here, we propose that the synergistic La-Ti active sites in the N-La2Ti2O7 nanosheets enable the highly selective carbon dioxide photoreduction into methane. In the photoreduction of CO2 over N-La2Ti2O7 nanosheets, in situ Fourier transform infrared spectra are utilized to monitor the *CH3O intermediate, pivotal for methane production, whereas such monitoring is not conducted for La2Ti2O7 nanosheets. Also, theoretical calculations testify to the increased charge densities on the Ti and La atoms and the regulated formation energy barrier of *CO and *CH3O intermediates by the constructed synergistic active sites. Accordingly, the methane formation rate of 7.97 μL h-1 exhibited by the N-La2Ti2O7 nanosheets, along with an electron selectivity of 96.6%, exceeds that of most previously reported catalysts under similar conditions.

Light-Driven C-C Coupling for Targeted Synthesis of CH3 COOH with Nearly 100 % Selectivity from CO2

Targeted synthesis of acetic acid (CH3 COOH) from CO2 photoreduction under mild conditions mainly limits by the kinetic challenge of the C-C coupling. Herein, we utilized doping engineering to build charge-asymmetrical metal pair sites for boosted C-C coupling, enhancing the activity and selectivity of CO2 photoreduction towards CH3 COOH. As a prototype, the Pd doped Co3 O4 atomic layers are synthesized, where the established charge-asymmetrical cobalt pair sites are verified by X-ray photoelectron spectroscopy and X-ray absorption near edge spectroscopy spectra. Theoretical calculations not only reveal the charge-asymmetrical cobalt pair sites caused by Pd atom doping, but also manifest the promoted C-C coupling of double *COOH intermediates through shortening of the coupled C-C bond distance from 1.54 to 1.52 Å and lowering their formation energy barrier from 0.77 to 0.33 eV. Importantly, the decreased reaction energy barrier from the protonation of two*COOH into *CO intermediates for the Pd-Co3 O4 atomic layer slab is 0.49 eV, higher than that of the Co3 O4 atomic layer slab (0.41 eV). Therefore, the Pd-Co3 O4 atomic layers exhibit the CH3 COOH evolution rate of ca. 13.8 μmol g-1  h-1 with near 100% selectivity, both of which outperform all previously reported single photocatalysts for CO2 photoreduction towards CH3 COOH under similar conditions.

Selective Photoreduction of CO2 to CH4 Triggered by Metal-Vacancy Pair Sites

Selectively achieving the photoreduction of carbon dioxide (CO2) to methane (CH4) remains a significant challenge, which primarily arises from the complexity of the protonation process. In this work, we designed metal-vacancy pair sites in defective metal oxide semiconductors, which anchor the reactive intermediates with a bridged linkage for the selective protonation to produce CH4. As an example, oxygen-deficient Nb2O5 nanosheets are synthesized, in which the niobium-oxygen vacancy pair sites are demonstrated by X-ray photoelectron spectroscopy and electron paramagnetic resonance spectra. In situ Fourier transform infrared spectroscopy monitors the *CH3O intermediate, a key intermediate for CH4 production, during the CO2 photoreduction in oxygen-deficient Nb2O5 nanosheets. Importantly, the built metal-vacancy pair sites regulate the *CH3O formation step as a spontaneous process, making the reduction of CO2 to CH4 the preferred method. Therefore, the oxygen-deficient Nb2O5 nanosheets exhibit a CH4 formation rate of 19.14 μmol g-1 h-1, with an electron selectivity of ∼94.1%.

Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Optimized full CO2 photoreduction process by defective spinel atomic layers

The impact of defects on the carbon dioxide (CO2) photoreduction property is sometimes contradictory. Herein, we employ two-dimensional materials, possessing high-density and high-uniformity active sites, as ideal models to thoroughly investigate the influence of defects on three main processes during CO2 photoreduction. As an example, oxygen-deficient ZnGa2O4 atomic layers are successfully fabricated, verified by the electron spin resonance spectra, X-ray photoelectron spectroscopy spectra and X-ray absorption near edge structure spectra. UV-vis diffuse reflectance spectra, photoluminescence spectra, surface photovoltage spectroscopy, N2 adsorption-desorption isotherm plots and density functional theory calculations indicate that the presence of oxygen defects helps to expand the photoabsorption, accelerate the carrier separation, and enhance the CO2 adsorption and protonation process. As a result, the carbon monoxide evolution rate of the defective ZnGa2O4 atomic layers was approximately 88 times higher than that of the ZnGa2O4 atomic layers under visible light irradiation. In other words, this work discloses that the introduction of defects on photocatalysts allows the optimization of the three primary processes, thus obtaining boosted CO2 photoreduction performance.

Fundamentals and Challenges of Engineering Charge Polarized Active Sites for CO2 Photoreduction toward C2 Products

ConspectusGlobal warming and climatic deterioration are partly caused by carbon dioxide (CO2) emission. Given this, CO2 reduction into valuable carbonaceous fuels is a win-win route to simultaneously alleviate the greenhouse effect and the energy crisis, where CO2 reduction into hydrocarbon fuels by solar energy may be a potential strategy. Up to now, most of the current photocatalysts photoconvert CO2 to C1 products. It is extremely difficult to achieve production of C2 products, which have higher economic value and energy density, due to the kinetic challenge of C-C coupling of the C1 intermediates. Therefore, to realize CO2 photoreduction to C2 fuels, design of high-activity photocatalysts to expedite the C-C coupling is significant. Besides, the current mechanism for CO2 photoreduction toward C2 fuels is usually uncertain, which is possibly attributed to the following two reasons: (1) It is arduous to determine the actual catalytic sites for the C-C coupling step. (2) It is hard to monitor the low-concentration active intermediates during the multielectron transfer step.Most traditional metal-based photocatalysts usually possess charge balanced active sites that have the same charge density. In this aspect, the neighboring C1 intermediates may also show the same charge distribution, which would lead to dipole-dipole repulsion, thus preventing C-C coupling for producing C2 fuels. By contrast, photocatalysts with charge polarized active sites possess obviously different charge distributions in the adjacent C1 intermediates, which can effectively suppress the electrostatic repulsion to steer the C-C coupling. Based on this analysis, higher asymmetric charge density on the active sites would be more beneficial to anchoring between the adjacent intermediates and active atoms in catalysts, which can boost C-C coupling.In this Account, we summarize various strategies, including vacancy engineering, doping engineering, loading engineering, and heterojunction engineering, for tailoring charge polarized active sites to boost the C-C coupling for the first time. Also, we overview diverse in situ characterization technologies, such as in situ X-ray photoelectron spectroscopy, in situ Raman spectroscopy, and in situ Fourier transform infrared spectroscopy, for determining charge polarized active sites and monitoring reaction intermediates, helping to reveal the internal catalytic mechanism of CO2 photoreduction toward C2 products. We hope this Account may help readers to understand the crucial function of charge polarized active sites during CO2 photoreduction toward C2 products and provide guidance for designing and preparing highly active catalysts for photocatalytic CO2 reduction.

Escherichia coli inhibits endometriosis by inducing M1 polarity of peritoneal macrophages and the IL-1 signaling pathway

The development of endometriosis is closely linked to macrophages, and the type M1 macrophage has been hypothesized to play an inhibitory role in its progression. Escherichia coli induces macrophage polarization toward M1 in numerous diseases and differs in the reproductive tract of patients with and without endometriosis; however, its specific role in endometriosis development remains unknown. Therefore, in this study, E. coli was selected as a stimulator to induce macrophages, and its effects on the growth of endometriosis lesions in vitro and in vivo were investigated using C57BL/6N female mice and endometrial cells. It was revealed that E. coli inhibited the migration and proliferation of co-cultured endometrial cells by IL-1 in vitro and prevented the growth of lesions and induced macrophage polarization toward M1 in vivo. However, this change was counteracted by C-C motif chemokine receptor 2 inhibitors, suggesting that it was associated with bone marrow-derived macrophages. Overall, the presence of E. coli in the abdominal cavity may be a protective factor for endometriosis.

Selective CO2 -to-C2 H4 Photoconversion Enabled by Oxygen-Mediated Triatomic Sites in Partially Oxidized Bimetallic Sulfide

Selective CO₂ photoreduction into C₂ fuels under mild conditions suffers from low product yield and poor selectivity owing to the kinetic challenge of C-C coupling. Here, triatomic sites are introduced into bimetallic sulfide to promote C-C coupling for selectively forming C₂ products. As an example, FeCoS₂ atomic layers with different oxidation degrees are first synthesized, demonstrated by X-ray photoelectron spectroscopy and X-ray absorption near edge spectroscopy spectra. Both experiment and theoretical calculation verify more charges aggregate around the introduced oxygen atom, which enables the original Co-Fe dual sites to turn into Co-O-Fe triatomic sites, thus promoting C-C coupling of double *COOH intermediates. Accordingly, the mildly oxidized FeCoS₂ atomic layers exhibit C₂ H₄ formation rate of 20.1 μmol g^-1  h^-1 , with the product selectivity and electron selectivity of 82.9 % and 96.7 %, outperforming most previously reported photocatalysts under similar conditions.

Progress and perspective for conversion of plastic wastes into valuable chemicals

Today, discarded plastics in nature have caused serious "white pollution", however these plastic wastes contain abundant carbon resources that could serve as the feedstock to produce commodities. Because of this, it is requisite to convert these plastic wastes into valuable chemicals. Herein, the state-of-the-art techniques for plastic conversion are divided into two categories, those performed under violent conditions and mild conditions, in which the conversion mechanisms are discussed. The strategies under violent conditions are closer to practical application thanks to their excellent conversion efficiencies, while the strategies under mild conditions are more environmentally friendly, showing enormous development potential in the future. We summarize in detail the pyrolysis, hydropyrolysis, solvolysis and microwave-initiated catalysis for bond cleavage in plastic wastes at temperatures ranging from 448 to 973 K. Also, we overview the photocatalysis, electrocatalysis and biocatalysis for bond cleavage in plastic wastes at near and even normal temperature and pressure. Finally, we present some suggestions and outlooks concerning the improvement of current techniques and in-depth mechanisms of investigation for conversion of plastics into valuable chemicals.

Direct Polyethylene Photoreforming into Exclusive Liquid Fuel over Charge-Asymmetrical Dual Sites under Mild Conditions

Direct polyethylene photoreforming to high-energy-density C₂ fuels under mild conditions is of great significance and still faces a huge challenge, which is partly attributed to the extreme instability of *CH₂CH₂ adsorbed on the traditional catalysts with single catalytic sites. Herein, charge-asymmetrical dual sites are designed to boost the adsorption of *CH₂CH₂ for direct polyethylene photoreforming into C₂ fuels under normal temperature and pressure. As a prototype, the synthetic Zr-doped CoFe₂O₄ quantum dots with charge-asymmetrical dual metal sites realize direct polyethylene photoreforming into acetic acid, with 100% selectivity of liquid fuel and the evolution rate of 1.10 mmol g^-1 h^-1, outperforming those of most previously reported photocatalysts under similar conditions. In situ X-ray photoelectron spectra, density-functional-theory calculations, and control experiments reveal the charge-asymmetrical Zr-Fe dual sites may act as the predominate catalytic sites, which can simultaneously bond with the *CH₂CH₂ intermediates for the following stepwise oxidation to form C₂ products.

Room-Temperature Photooxidation of CH4 to CH3OH with Nearly 100% Selectivity over Hetero-ZnO/Fe2O3 Porous Nanosheets

The huge challenge for CH₄ photooxidation into CH₃OH lies in the activation of the inert C-H bond and the inhibition of CH₃OH overoxidation. Herein, we design two-dimensional in-plane Z-scheme heterostructures composed of two different metal oxides, with efforts to polarize the symmetrical CH₄ molecules and strengthen the O-H bond in CH₃OH. As a prototype, we first fabricate ZnO/Fe₂O₃ porous nanosheets, where high-resolution transmission electron microscopy and in situ X-ray photoelectron spectroscopy affirm their in-plane Z-scheme heterostructure. In situ Fourier transform infrared spectra and in situ electron paramagnetic resonance spectra demonstrate their higher amount of ·CH₃ radicals relative to the pristine ZnO porous nanosheets, in which density functional theory calculations validate that the high local charge accumulation on Fe sites lowers the CH₄ adsorption energy from 0.14 to 0.06 eV. Moreover, the charge-accumulated Fe sites strengthen the polarity of the O-H bond in CH₃OH through transferring electrons to the O atoms, confirmed by the increased barrier from 0.30 to 2.63 eV for *CH₃O formation, which inhibits the homolytic O-H bond cleavage and thus suppresses CH₃OH overoxidation. Accordingly, the CH₃OH selectivity over ZnO/Fe₂O₃ porous nanosheets reaches up to nearly 100% with an activity of 178.3 μmol^-1 g_cat^-1, outperforming previously reported photocatalysts without adding any oxidants under room temperature and ambient pressure.

Plastics-to-Syngas Photocatalyzed by Co-Ga2O3 Nanosheets

Plastics take hundreds of years to degrade naturally, while their chemical degradation typically requires high temperature and pressure. Here, we first utilize solar energy to realize the sustainable and efficient plastic-to-syngas conversion with the aid of water at ambient conditions. As an example, the commercial plastic bags could be efficiently photoconverted into renewable syngas by Co–Ga₂O₃ nanosheets, with hydrogen and carbon monoxide formation rates of 647.8 and 158.3 μmol g⁻¹ h⁻¹. In situ characterizations and labelling experiments unveil water is photoreduced into hydrogen, while non-recyclable plastics including polyethylene bags, polypropylene boxes and polyethylene terephthalate bottles are photodegraded into carbon dioxide, which is further selectively photoreduced into carbon monoxide. In-depth investigation illustrates that the efficiency of syngas production mainly depends on the carbon dioxide reduction process and hence photocatalysts of high carbon dioxide reduction activity should be designed to promote the efficiency of plastic-to-syngas conversion in the future. The concept for the photoreforming of non-recyclable plastics into renewable syngas helps to eradicate ‘white pollution’ and alleviate the energy crisis simultaneously.

Selective CH4 Partial Photooxidation by Positively Charged Metal Clusters Anchored on Carbon Aerogel under Mild Conditions

Selective partial photooxidation of CH₄ into value-added chemicals under mild conditions still remains a huge bottleneck. Herein, we design positively charged metal clusters anchored on a three-dimensional porous carbon aerogel. With 0.75FeCA800-4 as an example, X-ray photoelectron spectra and Raman spectra disclose that the iron sites are positively charged. In situ electron paramagnetic resonance spectra show that the Fe^δ+ sites could donate electrons to activate CH₄ into CH₄^- by virtue of the excited-state carbon atoms; meanwhile, they could convert H₂O₂ into ^•OH radicals under irradiation. In addition, in situ diffuse Fourier-transform infrared spectra suggest the CH₃OOH obtained is derived from CH₄ oxidation by the hydroxylation of *CH₃ and *CH₃O intermediates. Consequently, 0.75FeCA800-4 displays a CH₃OOH selectivity of near 100% and a CH₃OOH evolution rate of 13.2 mmol g_Fe^-1 h^-1, higher than those of most previously reported supported catalysts under similar conditions.

Conversion of Waste Plastics into Value-Added Carbonaceous Fuels under Mild Conditions

Owing to the extremely difficult breakage of the adamant cross-linked structures, converting non-recyclable plastic wastes into valuable fuels usually demands rigorous conditions, wherein the required high temperature and pressure is inevitably energy-wasting and environment-polluting. Given this aspect, herein, the recent achievements in the conversion of plastics into value-added carbonaceous fuels under mild conditions are summarized. In detail, solar-driven conversion of commercial plastics into liquid fuels in alkaline solutions or pure water at ambient temperature and pressure are surveyed; also, enzyme-driven conversion of polyethylene terephthalate into terephthalic acid and ethylene glycol at a mild temperature are emphasized; and low-temperature-driven catalytic conversion of polyethylene into oils and waxes with the help of a light alkane are reviewed. Finally, other potentially used strategies and in situ characterization technologies in plastics degradation under moderate conditions are presented.

Asymmetric Triple-Atom Sites Confined in Ternary Oxide Enabling Selective CO2 Photothermal Reduction to Acetate

Light-induced heat is largely neglected in traditional photocatalytic systems, especially for the thermodynamically and kinetically challenging CO₂ reduction to C₂ fuels. Herein, we first design asymmetric Metal₁-O-Metal₂ triple-atom sites confined in phenakite to facilitate C-C coupling and employ photoinduced heat to increase molecular thermal vibration and accelerate CO₂ reduction to C₂ fuels. Using O-vacancy-rich Zn₂GeO₄ nanobelts as prototypes, quasi in situ Raman spectra disclose the Zn-O-Ge triatomic sites are likely the reactive sites. Density functional theory calculations reveal that the asymmetric Zn-O-Ge sites could promote C-C coupling through inducing distinct charge distributions of neighboring C₁ intermediates, whereas the created O vacancies could lower the energy barrier of the rate-determining hydrogenation step from 1.46 to 0.67 eV. Catalytic performances under different testing conditions demonstrate that light initiates the CO₂ reduction reaction. In situ Fourier-transform infrared spectra and D₂O kinetic isotopic effect experiments disclose that light-induced heat kinetically triggers C-C coupling and accelerates OCCO* hydrogenation via providing abundant hydrogen species. Consequently, in a simulated air atmosphere under 0.1 W/cm² illumination at 348 K, the O-vacancy-rich Zn₂GeO₄ nanobelts demonstrate an acetate output of 12.7 μmol g^-1 h^-1, a high acetate selectivity of 66.9%, a considerable CO₂-to-CH₃COOH conversion ratio of 29.95%, and a stability of up to 220 h.

Neutrophil-lymphocyte ratio and hypersensitive C-reaction protein are associated with miscarriage during the second trimester of pregnancy

This study investigated whether biomarkers in the second trimester of pregnancy, including the white blood cell (WBC) count, neutrophil-lymphocyte ratio (NLR), hypersensitive C-reactive protein (hs-CRP) concentration, and procalcitonin (PCT) concentration, were associated with miscarriage during the second trimester of pregnancy. Sixty-two asymptomatic patients in their second trimester of pregnancy were included in the control group (group A). Among 67 patients diagnosed with late threatened miscarriage, 46 patients with ongoing pregnancy were included in group B and 21 patients with subsequent miscarriage were included in group C. The serum of these patients was collected and the biomarkers were analyzed. A paired-samples t-test was used for the comparison between the groups before and after the miscarriage. Statistical significance was set at p<0.05. Receiver operating characteristic curve (ROC) analysis was performed to evaluate the predictive value of different biomarkers for miscarriage during the second trimester of pregnancy. WBC count, neutrophil percentage, and hs-CRP levels were significantly higher in group C than in groups A and B (p<0.05). Lymphocyte percentage and albumin levels decreased significantly from group A to group C (p<0.05). In contrast, NLR increased significantly from group A to group C (p<0.05). There was a significant decrease in the WBC count, neutrophil percentage, hemoglobin concentration, and post-miscarriage NLR among the cases with miscarriage (p<0.05). The area under the curve of WBC count, NLR, hs-CRP, and the combination of these three factors for the prediction of late miscarriage varied from 78.0% to 82.6%. The combination of these three factors had the highest specificity of 91.1%, while hs-CRP had the highest sensitivity of 88.9%. WBC count, NLR, and hs-CRP levels are strongly associated with miscarriage during the second trimester of pregnancy, indicating that they are potential predictive biomarkers.

Efficient Photooxidation of Methane to Liquid Oxygenates over ZnO Nanosheets at Atmospheric Pressure and Near Room Temperature

Direct CH₄ photoconversion into liquid oxygenates under mild conditions still represents a huge challenge. Herein, two-dimensional oxide semiconductors are designed to generate abundant active O^- species for activating C-H bond of methane. Taking the synthetic ZnO nanosheets as an example, in situ electron paramagnetic resonance spectra verified their lattice oxygen atoms could capture photoexcited holes and generate active O^- species, which could efficiently abstract H from CH₄ to generate ·CH₃ radicals. Gibbs free energy calculations and in situ Fourier-transform infrared spectroscopy corroborated the rate-limiting step was the first C-H bond activation process, whereas the exoergic oxidation of *CHO to HCOOH was easier than the endoergic overoxidation to CO, accounting for the selective production of liquid oxygenates. As a result, the formation rate of liquid oxygenates over ZnO nanosheets reached 2.21 mmol g^-1 h^-1 with a selectivity of 90.7% at atmospheric pressure and approximately 50 °C, outperforming previously reported photocatalysts under similar conditions.

Selective CO2 Photoreduction into C2 Product Enabled by Charge-Polarized Metal Pair Sites

Selective CO₂ photoreduction into a high-energy-density C₂ product is still challenging. Here, charge-polarized metal pair sites are designed to trigger C-C coupling through manipulating asymmetric charge distribution on the reduction intermediates. Taking the synthetic partially reduced Co₃O₄ nanosheets as an example, theoretical calculations unveil the asymmetric charge distribution on surface cobalt sites. The formed charge-polarized cobalt pair sites not only donate electrons to CO₂ molecules but also accelerate the coupling of asymmetric COOH* intermediates through lowering the energy barrier from 0.680 to 0.240 eV, affirmed by quasi in situ X-ray photoelectron spectroscopy and Gibbs free energy calculations. Also, the electron-rich cobalt sites strengthen their interaction with O of the HOOC-CH₂O* intermediate, which favors the C-O bond cleavage and hence facilitates the rate-limiting CH₃COOH desorption process. The partially reduced Co₃O₄ nanosheets achieve 92.5% selectivity of CH₃COOH in simulated air, while the CO₂-to-CH₃COOH conversion ratio is 2.75%, obviously higher than that in pure CO₂.

MicroRNA-26b-5p promotes development of neonatal respiratory distress syndrome by inhibiting differentiation of mesenchymal stem cells to type II of alveolar epithelial cells via regulating Wnt5a

OBJECTIVE

The aim was to investigate the role of microRNA-26b-5p in regulating mesenchymal stem cells (MSCs) differentiation to type II of alveolar epithelial cells (AECII) in the disease course of neonatal respiratory distress syndrome (NRDS).

MATERIALS AND METHODS

MSCs were first derived from rat bone marrow. In vitro induction of MSCs differentiation to AECII was conducted by SAGM. The mRNA levels of microRNA-26b-5p, Wnt5a, and AECII-related genes (Occludin, KGF, CK18, SpA, SpB, and SpC) during the process of cell differentiation were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Enzyme-linked immunosorbent assay (ELISA) was conducted for detecting levels of inflammatory factors tumor necrosis factor-α (TNF-α), interferon-α (INF-α), and interleukin-1 (IL-1) in cell supernatant. Dual-luciferase reporter gene assay was then carried out to verify the regulatory effect of microRNA-26b-5p on Wnt5a. MicroRNA-26b-5p expression in serum samples of NRDS neonates and healthy neonates was detected by qRT-PCR as well.

RESULTS

MicroRNA-26b-5p was overexpressed in NRDS neonates than those of healthy neonates. Besides, microRNA-26b-5p was highly expressed in the process of MSCs differentiation to AECII. MicroRNA-26b-5p overexpression remarkably inhibited AECII differentiation and Wnt5a expression. Levels of TNF-α, INF-α, and IL-1 in cell supernatant during differentiation induction were elevated. The regulatory effects of microRNA-26b-5p on AECII differentiation, Wnt5a expression, and inflammatory response were reversed by Wnt5a overexpression.

CONCLUSIONS

MicroRNA-26b-5p inhibits MSCs differentiation to AECII via inhibiting Wnt5a expression through the Wnt pathway.

[Changes of retinal structure after systemic immunosuppressive treatment in eyes with Vogt-Koyanagi-Harada disease]

Objective: To assess structural changes in retina after systemic immunosuppressive treatment in Vogt-Koyanagi-Harada (VKH) disease using spectral-domain optical coherence tomography (SD-OCT). Methods: The clinical data of 17 VKH cases (34 eyes) who consecutively attended the Beijing Tongren Hospital between December 2015 and December 2019 were retrospectively reviewed. All the patients had acute or subacute onset, and underwent high-dose systemic corticosteroid and/or immunosuppressive treatment, with a followed-up time of at least 6 months. At the end of follow-up, the intraocular inflammation was controlled, and oral prednisone was withdrawn or being adjusted to less than 10 mg/day. The SD-OCT features of the included eyes were analyzed before treatment, 1 week, 1 month and 3 months after treatment, and at the last visit. Results: A total of 17 cases (34 eyes; 6 males and 11 females) were included, with an age of (42.2±10.6) years, and were followed up for (9.4±3.3) months. At 1 week after initiating treatment, the percentage of the eyes with extensive/multiple or multifocal retinal detachment in the macular region, membranous structures and intraretinal cysts, and undulations and bumps of retinal pigment epithelium (RPE) decreased (5.9% vs 100%, 2.9% vs 47.1%, 5.9% vs 70.6%, 11.8% vs 58.8%, respectively, all P<0.001). There was statistical significant difference of the percentage of ellipsoid zone and external limiting membrane (ELM) disruptions before treatment, at 3 months and the last visit (100% vs 35.3%, 64.7% vs 52.9%, 41.2% vs 26.5%, respectively, all P<0.001). At the last visit, there were statistical significant differences of the best corrected vision acuity (BCVA) between the intact ellipsoid zone group (20 eyes) and the discontinuous group (14 eyes), as well as between the intact ELM group (25 eyes) and the discontinuous group (9 eyes), respectively [0 (0, 0.05) vs 0.10 (0.03, 0.33) (log MAR), P=0.004; 0 (0, 0.07) vs 0.22 (0.05, 0.40) (log MAR), P=0.005]. Conclusions: The edema of choroid and retina subsided obviously at 1 week after initiating treatment. The extent of damage and recovery ability of ellipsoid zone and ELM were different before treatment, at 3 months and the last visit. At the last visit, the outer retinal layers failed to recover completely in some patients, and were related to the BCVA.

Broad-Spectral-Response Photocatalysts for CO2 Reduction

The poor conversion efficiency of carbon dioxide photoreduction has hindered the practical application at present, and one of the prime reasons for this obstacle is the inefficient solar energy utilization of photocatalysts. Generally speaking, it is contradictory for a photocatalyst to concurrently possess the broad-spectral response and appropriate band-edge positions for coinstantaneous carbon dioxide reduction and water oxidation. In this Outlook, we summarize a series of strategies for realizing visible-light and IR-light-driven carbon dioxide photoreduction under the guarantee of suitable band-edge positions. In detail, we overview the absorbance of visible light enabled by narrow band gaps in photocatalysts, the extended photoabsorption from UV into the visible light range induced by defect levels and dopant energy levels in photocatalysts, and a more negative conduction band and positive valence band acquired by Z-scheme heterojunctions in photocatalysts. Then, we highlight the expansive photoresponse of IR light caused by intermediate bands in semiconductor photocatalysts and partially occupied bands in conductor photocatalysts. Finally, we end this Outlook concerning more design strategies and application fields of broad-spectral-response photocatalysts.

Fundamentals and challenges of ultrathin 2D photocatalysts in boosting CO2 photoreduction

Ultrathin 2D materials serve as ideal models for tailoring three crucial parameters that determine CO₂ photoconversion efficiency and product selectivity.

The accuracy of bone mineral density measurement using dual-energy spectral CT and quantitative CT: a comparative phantom study

AIM

To compare bone mineral density (BMD) measurement accuracy by dual-energy spectral computed tomography (CT) and quantitative CT (QCT) using an anthropomorphic European spine phantom (ESP).

MATERIALS AND METHODS

An ESP containing three hydroxyapatite inserts with densities of 50, 100, and 200 mg/cm³ was scanned 10 times each using spectral CT and QCT protocols. Their BMD values were measured using hydroxyapatite-based spectral CT material decomposition images and QCT images and compared with the true values in ESP.

RESULTS

Both protocols had good repeatability in BMD measurement with low coefficient-of-variance (spectral CT: <2.31%; QCT: <1.17%). There were biases in BMD measurement for the 50, 100, and 200 mg/cm³ hydroxyapatite insert with relative errors of 2.34% (48.83±1.13 mg/cm³), 2% (98±1.25 mg/cm³) and 5.96% (188.09±2.11 mg/cm³), in spectral CT, and 11% (55.5±0.65 mg/cm³), 9.85% (109.85±0.42 mg/cm³) and 4.04% (208.07±0.54 mg/cm³) in QCT, respectively.

CONCLUSION

BMD can be accurately measured using either QCT or spectral CT, and spectral CT has smaller bias than QCT.

Molecular cloning and functional characterisation of duck (Anas platyrhynchos) tumour necrosis factor receptor-associated factor 3

1. Tumour necrosis factor receptor-associated factor 3 (TRAF3) is a key regulator of innate immunity and acquired immunity, and has a salient anti-viral role. 2. In this experiment, the duck TRAF3 (DuTRAF3) gene was cloned according to the Anas platyrhynchos TRAF3 sequence to explore its function. The TRAF3 open reading frame contains 1704 bp that encode a protein of 567 amino acids, which contain a RING finger domain, two zinc finger motifs, a coiled-coil region, and a MATH domain. 3. Reverse transcription-polymerase chain reaction showed that DuTRAF3 was expressed in all the examined tissues, with a comparatively higher expression in the spleen and brain tissues. 4. In HEK293T cells, DuTRAF3 overexpression resulted in a significantly increased NF-κB activity and interferon (IFN)-β promoter activation. 5. Following resiquimod (R848) and poly(I:C) stimulation of duck peripheral blood mononuclear cells (PBMCs), the expressions of TRAF3 and IFN-β were significantly upregulated; in addition, following R848 stimulation, the mRNA levels of IL-6, IL-8 and IL-10 were also significantly upregulated. After infection with the Newcastle Disease Virus LaSota vaccine strain, the mRNA levels of IL-6 and IL-10 were significantly upregulated, while that of TRAF3 was downregulated. 6. These results suggest that DuTRAF3 has an important role to play in innate antiviral immune responses.

Gradient magnet design for simultaneous detection of electrons and positrons in the intermediate MeV range

We report the design and development of a compact electron and positron spectrometer based on tapered neodymium iron boron magnets to characterize the pairs generated in laser-matter experiments. The tapered design forms a gradient magnetic field component allowing energy dependent focusing of the dispersed charged particles along a chosen detector plane. The mirror symmetric design allows for simultaneous detection of pairs with energies from 2 MeV to 500 MeV with an accuracy of ≤10% in the wide energy range from 5 to 110 MeV for a parallel beam incident on a circular aperture of 20 mm. The energy resolution drops to ≤20% for 4-90 MeV range for a divergent beam originating from a point source at 20 cm away (i.e., a solid angle of ∼8 milli steradians), with ≤10% accuracy still maintained in the narrower energy range from 10 to 55 MeV. It offers higher solid angle acceptance, even for the divergent beam, compared to the conventional pinhole aperture-based spectrometers. The proposed gradient magnet is suitable for the detection of low flux and/or monoenergetic type electron/positron beams with finite transverse sizes and offers unparalleled advantages for gamma-ray spectroscopy in the intermediate MeV range.

Visible-Light-Driven Overall Water Splitting Boosted by Tetrahedrally Coordinated Blende Cobalt(II) Oxide Atomic Layers

Directly splitting water into H₂ and O₂ with solar light is extremely important; however, the overall efficiency of water splitting still remains extremely low. Two types of ultrathin semiconductor layers with the same elements and the same thicknesses were designed to uncover how different atomic arrangements influence water-splitting efficiency thermodynamically and kinetically. As an example, tetrahedrally coordinated blende and octahedrally coordinated rocksalt CoO atomic layers with nearly the same thicknesses were synthesized for the first time. The blende CoO atomic layers have a smaller E_g and abundant d-d internal transition features relative to the rocksalt CoO atomic layers, which ensure enhanced visible-light harvesting ability. Density functional theory calculations reveal that the Bader charge for Co atoms in blende CoO atomic layers is larger than that of the rocksalt CoO atomic layers, which facilitates photocarrier transfer kinetics, as verified by photoluminescence spectra and time-resolved fluorescence emission decay spectra. In situ FTIR spectra and energy calculations reveal that the *OOH dissociation step is the rate-limiting step, where the blende CoO atomic layers possess a smaller *OOH dissociation energy thanks to their higher Bader charge and stronger steric effect, as confirmed by the elongated Co-OOH bonds. The blende CoO atomic layers exhibit visible-light-driven H₂ and O₂ formation rates of 4.43 and 2.63 μmol g^-1  h^-1 , roughly 3.7 times higher than those of the rocksalt CoO atomic layers.

Efficient Visible-Light-Driven CO2 Reduction Mediated by Defect-Engineered BiOBr Atomic Layers

Solar CO₂ reduction efficiency is largely limited by poor photoabsorption, sluggish electron-hole separation, and a high CO₂ activation barrier. Defect engineering was employed to optimize these crucial processes. As a prototype, BiOBr atomic layers were fabricated and abundant oxygen vacancies were deliberately created on their surfaces. X-ray absorption near-edge structure and electron paramagnetic resonance spectra confirm the formation of oxygen vacancies. Theoretical calculations reveal the creation of new defect levels resulting from the oxygen vacancies, which extends the photoresponse into the visible-light region. The charge delocalization around the oxygen vacancies contributes to CO₂ conversion into COOH* intermediate, which was confirmed by in situ Fourier-transform infrared spectroscopy. Surface photovoltage spectra and time-resolved fluorescence emission decay spectra indicate that the introduced oxygen vacancies promote the separation of carriers. As a result, the oxygen-deficient BiOBr atomic layers achieve visible-light-driven CO₂ reduction with a CO formation rate of 87.4 μmol g^-1  h^-1 , which was not only 20 and 24 times higher than that of BiOBr atomic layers and bulk BiOBr, respectively, but also outperformed most previously reported single photocatalysts under comparable conditions.

Highly Efficient and Exceptionally Durable CO2 Photoreduction to Methanol over Freestanding Defective Single-Unit-Cell Bismuth Vanadate Layers

Unearthing an ideal model for disclosing the role of defect sites in solar CO₂ reduction remains a great challenge. Here, freestanding gram-scale single-unit-cell o-BiVO₄ layers are successfully synthesized for the first time. Positron annihilation spectrometry and X-ray fluorescence unveil their distinct vanadium vacancy concentrations. Density functional calculations reveal that the introduction of vanadium vacancies brings a new defect level and higher hole concentration near Fermi level, resulting in increased photoabsorption and superior electronic conductivity. The higher surface photovoltage intensity of single-unit-cell o-BiVO₄ layers with rich vanadium vacancies ensures their higher carriers separation efficiency, further confirmed by the increased carriers lifetime from 74.5 to 143.6 ns revealed by time-resolved fluorescence emission decay spectra. As a result, single-unit-cell o-BiVO₄ layers with rich vanadium vacancies exhibit a high methanol formation rate up to 398.3 μmol g^-1 h^-1 and an apparent quantum efficiency of 5.96% at 350 nm, much larger than that of single-unit-cell o-BiVO₄ layers with poor vanadium vacancies, and also the former's catalytic activity proceeds without deactivation even after 96 h. This highly efficient and spectrally stable CO₂ photoconversion performances hold great promise for practical implementation of solar fuel production.