Defect-Induced All-Solid-State Frustrated Lewis Pair on Metal-Organic Monolayer Accelerating Photocatalytic CO2 Reduction with H2O Vapor.

Understanding the structure-performance relationships of a frustrated Lewis pair (FLP) at the atomic level is key to yielding high efficiency in activating chemically "inert" molecules into value-added products. A sound strategy was developed herein through incorporating oxygen defects into a Zr-based metal-organic layer (Zr-MOL-D) and employing Lewis basic proximal surface hydroxyls for the in situ formation of solid heterogeneous FLP (Zr4-δ-VO-Zr-OH). Zr-MOL-D exhibits a superior CO2 to CO conversion rate of 49.4 µmol g-1 h-1 in water vapor without any sacrificing agent or photosensitizer, which is about 12 times higher than that of pure MOL (Zr-MOL-P), with extreme stability even after being placed for half a year. Theoretical and experimental results reveal that the introduction of FLP converts the process of the crucial intermediate COOH* from an endothermic reaction to an exothermic spontaneous reaction. This work is expected to provide new prospects for developing efficient MOL-based photocatalysts in FLP chemistry through a sound defect-engineering strategy.

Wireless rotating bipolar electrochemiluminescence for enzymatic detection.

New dynamic, wireless and cost-effective analytical devices are developing rapidly in biochemical analysis. Here, we report on a remotely-controlled rotating electrochemiluminescence (ECL) sensing system for enzymatic detection of a model analyte, glucose, on both polarized sides of an iron wire acting as a bipolar electrode. The iron wire is controlled by double contactless mode, involving remote electric field polarization, and magnetic field-induced rotational motion. The former triggers the interfacial polarization of both extremities of the wire by bipolar electrochemistry, which generates ECL emission of the luminol derivative (L-012) with the enzymatically produced hydrogen peroxide in presence of glucose, at both anodic and cathodic poles, simultaneously. The latter generates a convective flow, leading to an increase in mass transfer and amplifying the corresponding ECL signals. Quantitative glucose detection in human serum samples is achieved. The ECL signals were found to be a linear function of the glucose concentration within the range of 10-1000 µM and with a limit of detection of 10 µM. The dynamic bipolar ECL system simultaneously generates light emissions at both anodic and cathodic poles for glucose detection, which can be further applied to biosensing and imaging in autonomous devices.

Self-assembly of a AuNPs/Ti3C2 MXene hydrogel for cascade amplification of microRNA-122 biosensing.

A three-dimensional (3D) self-assembled AuNPs/Ti3C2 MXene hydrogel (AuNPs/Ti3C2 MXH) nanocomposite was prepared for the fabrication of a novel microRNA-122 electrochemical biosensor. The 3D hydrogel structure was gelated from two-dimensional MXene nanosheets with the assistance of graphite oxide and ethylenediamine. MXene hydrogels supported the in situ formation of Au nanoparticles (AuNPs) that predominantly exploring the (111) facet, and these AuNPs are utilized as carriers for hairpin DNA (hpDNA) probes, facilitating DNA hybridization. MXene acted as both a reductant and stabilizer, significantly improving the electrochemical signal. In addition, the conjugation of PAMAM dendrimer-encapsulated AuNPs and H-DNA worked as an ideal bridge to connect targets and efficient electrochemical tags, providing a high amplification efficiency for the sensing of microRNA-122. A linear relationship between the peak currents and the logarithm of the concentrations of microRNA-122 from 1.0 × 10-2 to 1.0 × 102 fM (I = 1.642 + 0.312 lgc, R2 = 0.9891), is obtained. The detection limit is  0.8 × 10-2 fM (S/N = 3). The average recovery for human serum detection ranged from 97.32 to 101.4% (RSD < 5%).

Covalent Organic Framework with Multiple Redox Active Sites for High-Performance Aqueous Calcium Ion Batteries.

Organic materials are promising for cation storage in calcium ion batteries (CIBs). However, the high solubility of organic materials in an electrolyte and low electronic conductivity remain the key challenges for high-performance CIBs. Herein, a nitrogen-rich covalent organic framework with multiple carbonyls (TB-COF) is designed as an aqueous anode to address those obstacles. TB-COF demonstrates a high reversible capacity of 253 mAh g-1 at 1.0 A g-1 and long cycle life (0.01% capacity decay per cycle at 5 A g-1 after 3000 cycles). The redox mechanism of Ca2+/H+ co-intercalated in COF and chelating with C═O and C═N active sites is validated. In addition, a novel C═C active site was identified for Ca2+ ion storage. Both computational and empirical results reveal that per TB-COF repetitive unit, up to nine Ca2+ ions are stored after three staggered intercalation steps, involving three distinct Ca2+ ion storage sites. Finally, the evolution process of radical intermediates further elucidates the C═C reaction mechanism.

Topological Insulator Bi2 Se3 -Assisted Heterostructure for Ultrafast Charging Sodium-Ion Batteries.

The development of fast charging materials offers a viable solution for large-scale and sustainable energy storage needs. However, it remains a critical challenge to improve the electrical and ionic conductivity for better performance. Topological insulator (TI), a topological quantum material that has attracted worldwide attention, hosts unusual metallic surface states and consequent high carrier mobility. Nevertheless, its potential in promising high-rate charging capability has not been fully realized and explored. Herein, a novel Bi2 Se3 -ZnSe heterostructure as excellent fast charging material for Na+ storage is reported. Ultrathin Bi2 Se3 nanoplates with rich TI metallic surfaces are introduced as an electronic platform inside the material, which greatly reduces the charge transfer resistance and improves the overall electrical conductivity. Meanwhile, the abundant crystalline interfaces between these two selenides promote Na+ migration and provide additional active sites as well. As expected, the composite delivers the excellent high-rate performance of 360.5 mAh g-1 at 20 A g-1 and maintains its electrochemical stability of 318.4 mAh g-1 after 3000 long cycles, which is the record high for all reported selenide-based anodes. This work is anticipated to provide alternative strategies for further exploration of topological insulators and advanced heterostructures.

Update to the Newly Developed Expression for the Stability Ratio of Colloidal Dispersions.

The colloidal stability, one of the basic and important properties of a colloidal dispersion, is commonly evaluated in terms of the stability ratio. In this study, a recently developed expression for the stability ratio is updated, by reformulating the fraction of successful collisions leading to secondary minimum coagulation. The updated formula reinterprets the statistical meaning of the fraction of successful collisions leading to primary or secondary minimum coagulation, ensuring that the total fraction of successful collisions is always less than or equals to 1. It was shown to be superior to the available expressions in accounting for the contribution of the primary and secondary minimum coagulations on the stability ratio. It can well interpret the stability of colloidal dispersions of spherical particles; moreover, it is of great potential to be applied to colloidal dispersions of plate-like particles. In addition, this formula is found to be consistent with the concept of the critical coagulation concentration and well interpret the effects of particle size, counterion valence, surface potential, and Hamaker constant on the colloidal stability.

Salvage Esophagectomy After Definitive Chemoradiotherapy for Squamous Cell Esophageal Cancer: A Propensity Score Matching Study in a High-Volume Center.

BACKGROUND: Salvage esophagectomy, indicated for some patients with locally recurrent/persistent disease after definitive chemoradiotherapy (dCRT), reportedly has high postoperative complications. This study aims to compare the safety and efficacy of dCRT followed by salvage esophagectomy (DCRE) with planned esophagectomy after neoadjuvant chemoradiotherapy (NCRE) in esophageal squamous cell carcinoma (ESCC). METHODS: We retrospectively reviewed all locally advanced ESCC patients treated with DCRE or NCRE at Shanghai Chest Hospital from 2018 to 2021. Propensity score matching (PSM) was used to balance baseline differences. DCRE is defined as esophagectomy for recurrent/persistent disease after dCRT. RESULTS: A total of 302 patients (41 for DCRE and 261 for NCRE) were included. The median interval of chemoradiotherapy-to-surgery was 47d in NCRE, 43d and 440d in DCRE of persistent disease (n = 24) and recurrence (n = 17), respectively. DCRE was observed with advanced ypT stage (63% vs 38%), poorer differentiation (32% vs 15%) and more lymphovascular invasion (29% vs 11%) compared with NCRE (all p < 0.05). The above factors were comparable between the two groups after PSM (all p > 0.05). There were no significant differences before and after PSM in postoperative complications over Clavien-Dindo grade III (e.g., respiratory failure and anastomotic leak), 30/90-day postoperative mortality, and survival. CONCLUSION: Through a standardized surgical procedure in a high-volume center, DCRE exhibited comparable postoperative complications and prognosis with NCRE.

Quantitative Evaluation of Carrier Dynamics in Full-Spectrum Responsive Metallic ZnIn2S4 with Indium Vacancies for Boosting Photocatalytic CO2 Reduction.

The influence of defects on quantitative carrier dynamics is still unclear. Therefore, full-spectrum responsive metallic ZnIn2S4 (VIn-rich-ZIS) rich in indium vacancies and exhibiting high CO2 photoreduction efficiency was synthesized for the first time. The influence of the defects on the carrier dynamic parameters was studied quantitatively; the results showed that the minority carrier diffusion length (LD) is closely related to the catalytic performance. In situ infrared spectroscopy and theoretical calculations revealed that the presence of indium vacancies lowers the energy barrier for CO2 to CO conversion via the COOH* intermediate. Hence, the high rate of CO evolution reaches 298.0 µmol g-1 h-1, a nearly 28-fold enhancement over that with ZnIn2S4 (VIn-poor-ZIS), which is not rich in indium vacancies. This work fills the gaps between the catalytic performance of defective photocatalysts and their carrier dynamics and may offer valuable insight for understanding the mechanism of photocatalysis and designing more efficient defective photocatalysts.

Mechanistic Insights into the Anti-Proliferative Action of Gut Microbial Metabolites against Breast Adenocarcinoma Cells.

The gut microbiota undergoes metabolic processes to produce by-products (gut metabolites), which play a vital role in the overall maintenance of health and prevention of disease within the body. However, the use of gut metabolites as anticancer agents and their molecular mechanisms of action are largely unknown. Therefore, this study evaluated the anti-proliferative effects of three key gut microbial metabolites-sodium butyrate, inosine, and nisin, against MCF7 and MDA-MB-231 breast adenocarcinoma cell lines. To determine the potential mechanistic action of these gut metabolites, flow cytometric assessments of apoptotic potential, reactive oxygen species (ROS) production measurements and proteomics analyses were performed. Sodium butyrate exhibited promising cytotoxicity, with IC50 values of 5.23 mM and 5.06 mM against MCF7 and MDA-MB-231 cells, respectively. All three metabolites were found to induce apoptotic cell death and inhibit the production of ROS in both cell lines. Nisin and inosine indicated a potential activation of cell cycle processes. Sodium butyrate indicated the possible initiation of signal transduction processes and cellular responses to stimuli. Further investigations are necessary to ascertain the effective therapeutic dose of these metabolites, and future research on patient-derived tumour spheroids will provide insights into the potential use of these gut metabolites in cancer therapy.

Comparison of prone-supine versus supine position for the treatment of pilon fractures via modified posteromedial approach combined with anterolateral approach.

BACKGROUND: Most of modified posteromedial approaches require prone position for the treatment of pilon fractures. We describe the technique of modified posteromedial approach under supine position. The goal of the study was to compare the radiographic and clinical outcomes of prone-supine versus supine position for the treatment of pilon fractures via modified posteromedial approach combined with anterolateral approach. METHODS: A total of 50 retrospectively consecutive pilon fractures that underwent open reduction internal fixation via modified posteromedial approach combined with anterolateral approach from 2016 to 2019 were reviewed at least a two-year follow up. The positions of patients were divided into two groups: prone-supine versus supine position (26 vs 24, respectively). The operation time, radiographic outcomes including bone union time and ratio of congruent articular reduction were evaluated. The post-operative function was evaluated using the Manchester Oxford score (MOXFQ) and the visual analogue score (VAS). The motion of ankle joint and complications and were also compared. RESULTS: The mean follow-up was 42.2(24.7-73.0) months in the prone-supine group and 42.7(37.3-56.5) months in the supine group (P = .87). The mean operation time was 141.9 ± 10.1 min in the prone-supine group and 107.5 ± 18.9 min in the supine group (P = .00). There was no significant difference in the bone union time and ratio of congruent articular reduction between the two groups. There was no significant difference in the final MOXFQ score, VAS score, and the mean range of ankle motion between the two groups (P > .05). The total incidence of complications was 11.5% in the prone-supine group and 16.6% in the supine group (P = .66). CONCLUSION: The patient in the prone-supine position versus supine position for pilon fractures via modified posteromedial approach combined with anterolateral approach contributed comparable quality of reduction, bone union time functional outcomes and complications. The supine technique was significantly shorter in terms of operation time.

Polysaccharides from apple pomace exhibit anti-fatigue activity through increasing glycogen content.

The polysaccharides were isolated from apple pomace by hot-water extraction, and their anti-fatigue activity was evaluated in C2C12 muscle myoblasts and male Kunming mice. The purified polysaccharides from apple pomace (PAP) have a molecular weight of 1.74 × 105 Da and were composed of mannose, rhamnose, glucose, galactose and arabinose. In C2C12 myoblasts, PAP showed no cytotoxicity in the concentrations of 0-300 µg/ml. PAP treatment increased the glycogen content, while the ATP content was not affected in C2C12 myoblasts. Further investigation found that the activity and gene expression of glycogen synthase, rather than glycogen phosphorylase, were upregulated by PAP treatment. The studies in vivo showed that PAP treatment did not affect the food intake and weight again in mice. Importantly, PAP prolonged the exhaustive swimming time, increased hepatic and skeletal muscle glycogen levels, and effectively inhibited the accumulation of blood lactic and blood urea nitrogen in mice. Taken together, the results suggested that PAP exhibit anti-fatigue activity in vitro and in vivo through increasing glycogen content.

Rich Indium-Vacancies In2 S3 with Atomic p-n Homojunction for Boosting Photocatalytic Multifunctional Properties.

Design and development of highly efficient photocatalytic materials are key to employ photocatalytic technology as a sound solution to energy and environment related challenges. This work aims to significantly boost photocatalytic activity through rich indium vacancies (VIn ) In2 S3 with atomic p-n homojunction through a one-pot preparation strategy. Positron annihilation spectroscopy and electron paramagnetic resonance reveal existence of VIn in the prepared photocatalysts. Mott-Schottky plots and surface photovoltage spectra prove rich VIn In2 S3 can form atomic p-n homojunction. It is validated that p-n homojunction can effectively separate carriers combined with photoelectrochemical tests. VIn decreases carrier transport activation energy (CTAE) from 0.64 eV of VIn -poor In2 S3 to 0.44 eV of VIn -rich In2 S3 . The special structure endows defective In2 S3 with multifunctional photocatalysis properties, i.e., hydrogen production (872.7 µmol g-1 h-1 ), degradation of methyl orange (20 min, 97%), and reduction in heavy metal ions Cr(VI) (30 min, 98%) under simulated sunlight, which outperforms a variety of existing In2 S3 composite catalysts. Therefore, such a compositional strategy and mechanistic study are expected to offer new insights for designing highly efficient photocatalysts through defect engineering.

High-Performance Aqueous Zinc-Ion Battery Based on an Al0.35 Mn2.52 O4 Cathode: A Design Strategy from Defect Engineering and Atomic Composition Tuning.

Rechargeable zinc-ion batteries (ZIBs), which adopt mild aqueous electrolytes with high power density and safety, have received significant interest. As the most widely used cathode material for ZIBs, manganese-based oxide has poor rate performance owing to its low electronic conductivity and slow ion diffusion kinetics. In this study, using the synergistic regulation strategy of defect engineering and atomic composition tuning, a mesoporous Al0.35 Mn2.52 O4 with an ultrahigh surface area (up to 82 m2 g-1 ) is fabricated through Al substitution in the Mn3 O4 , followed by an Al-selective leaching process. During the entire process, numerous defects are obtained in the spinel structure by removing ≈30% of the Al cations. Al substitution can improve the material conductivity, while cation defects can weaken the electrostatic effect and promote ion diffusion ability. Therefore, the Al0.35 Mn2.52 O4 cathode of ZIBs exhibits a high reversible capacity of 302 mAh g-1 at a current density of 100 mA g-1 . Furthermore, the reversible capacity remains at 147 mAh g-1 after 1000 cycles at a current density of 1500 mA g-1 . This synergistic regulation of atomic composition tuning and defect engineering provides a new perspective for improving the performance of electrode materials in ZIBs.

Revisiting the Theory of Coagulation of Colloidal Dispersions: An Improved Expression for the Stability Ratio.

The stability of a colloidal dispersion has long been expressed in terms of the stability ratio. Based on the available theories of coagulation of colloidal dispersions, a novel expression, complying with the classical definition, is developed for the stability ratio. It accounts for the contributions of both primary and secondary minimum coagulations to the overall rate of coagulations. In addition, it can also be regarded as the result of a combination of the kinetic theory of an ideal gas and the Smoluchowski theory with Fuchs' correction, considering the interaction between identical spherical particles and their surfaces immersed in a symmetrical electrolyte solution. The agreement with experimental data suggested that it is superior to the classical ones in describing the weak dependence of the stability ratio on the particle size and the valence of the counterion, by emphasizing the importance of the secondary minimum coagulation in dispersion stability and the complementation between the two modes of coagulation.

Development of a mid-infrared sensor system for early fire identification in cotton harvesting operations.

To realize early fire identification in cotton harvesting operations, a mid-infrared carbon monoxide (CO) sensor system was developed. To match the broadband light source with a 15° divergence angle, a multipass gas cell (MPGC) with an effective path length of 180 cm was designed to improve sensor sensitivity, leading to a limit of detection (LoD) of 0.83 parts-per-million by volume (ppmv). A damping module with springs at the bottom and front/back sides was fabricated, which can effectively reduce the vibration intensity by >80%. The sensor system can operate normally from -40 °C to 85 °C by stabilizing the temperature of the optical module through heating or cooling as well as using automotive electronic components. An adaptive early fire identification algorithm based on a dual-parameter threshold alarming method was proposed to avoid false and missing alarms. Field deployments on a harvester verified the good practicability of the sensor system.

Catalase-integrated metal-organic framework with synergetic catalytic activity for colorimetric sensing.

As a platform for enzyme immobilization, metal-organic frameworks (MOFs) can protect enzyme activity from the interference of external adverse environment. Although these strategies have been proven to produce good results, little consideration has been given to the functional similarity of MOFs to the encapsulated enzyme. Here, catalase (CAT) was encapsulated in Fe-BTC with peroxidase-like activity to obtain a stable composite (CAT@Fe-BTC) with synergistic catalytic activity. Depending on the superior selectivity and high catalytic activity of CAT@Fe-BTC, colorimetric sensing for the detection of hydrogen peroxide and phenol was developed. This work demonstrates that the integration of functional MOFs with natural enzyme can be well applied to the construction of efficient catalysts.

Fabrication of Pt doped TiO2-ZnO@ZIF-8 core@shell photocatalyst with enhanced activity for phenol degradation.

Phenol's presence in aqueous solution due to the pollution from chemical and agricultural industries (e.g., coking tobacco leaves) causes severe environmental problems. As a result, many scientists and engineers search for catalysts to remove phenol from water by photodegradation. Thus, we synthesized Pt-doped TiO2-ZnO@ZIF-8 core@shell particles (Pt/TiO2-ZnO@ZIF-8) by a simple method involving crystallization, absorption, pyrolysis and growth steps. The resulting materials were analyzed by the powder X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM and TEM, respectively), surface area measurements and UV-vis absorption spectroscopy. The photocatalytic activities of our materials were evaluated by phenol degradation in aqueous solutions. Pt-doped TiO2-ZnO particles possessed a polyhedral structure and exhibited broad absorption above 400 nm. Coating with ZIF-8 increased the specific surface area of the Pt-doped TiO2-ZnO particles. Both Pt doping and ZIF-8 coating significantly enhanced the photocatalytic performance of TiO2-ZnO. Pt/TiO2-ZnO@ZIF-8 decomposed 99.7 % of phenol after the corresponding solution was exposed to UV light for 24 min. This performance was significantly better than the phenol decomposition ability of TiO2-ZnO, Pt/TiO2-ZnO and TiO2, which degraded 76.1 %, 95.2 % and 86.9 % of phenol, respectively. Pt/TiO2-ZnO@ZIF-8 also demonstrated excellent recycling stability. All these properties, including photostability, made our novel Pt/TiO2-ZnO@ZIF-8 catalyst a promising material for practical applications in environmental remediation.

A Rat Model of Esophagogastric Anastomotic Stricture.

Esophagogastric anastomosis stricture is one of the most common postoperative complications after esophagectomy; yet, its pathogenesis is still not fully understood, and the treatment and prevention of anastomotic stricture are limited due to the lack of a proper animal model. The insufficient blood supply in the gastric tube is considered a risk factor for postoperative anastomotic strictures. In this study, we used thermal imaging to develop a stable rodent model with esophagogastric anastomotic stricture caused by ischemia. Briefly, 30 male Sprague-Dawley rats have been divided into the control group and the ischemia group. The esophagogastric ischemia anastomosis was performed with the help of intraoperative thermal imaging to identify the poor perfusion area. An unpaired t test with Welch's correction was used to analyze the difference between the two groups. On postoperative day 84, in the control group, no anastomosis stricture was observed, while in the ischemia group, 12 out of 15 animals (80%) developed obvious anastomosis stricture which could not let a 2.7-mm endoscope pass through. The diameter of the anastomosis in the control group and the ischemia group were 2.80 ± 0.15 mm and 1.73 ± 0.44 mm (p < 0.01), respectively (evaluated by endoscopy examination and barium radiography). H&E stain and Masson's trichrome showed that the anastomosis in the ischemia group had more connective tissue hyperplasia and collagen deposition than control group. Thus, this new rat model can be used as a platform to further investigate the potential interventions for prevention of esophagogastric anastomotic stricture.

Tumor-Associated-Macrophage-Membrane-Coated Nanoparticles for Improved Photodynamic Immunotherapy.

Cell-membrane-coated nanoparticles have emerged as a promising antitumor therapeutic strategy. However, the immunologic mechanism remains elusive, and there are still crucial issues to be addressed including tumor-homing capacity, immune incompatibility, and immunogenicity. Here, we reported a tumor-associated macrophage membrane (TAMM) derived from the primary tumor with unique antigen-homing affinity capacity and immune compatibility. TAMM could deplete the CSF1 secreted by tumor cells in the tumor microenvironment (TME), blocking the interaction between TAM and cancer cells. Especially, after coating TAMM to upconversion nanoparticle with conjugated photosensitizer (NPR@TAMM), NPR@TAMM-mediated photodynamic immunotherapy switched the activation of macrophages from an immunosuppressive M2-like phenotype to a more inflammatory M1-like state, induced immunogenic cell death, and consequently enhanced the antitumor immunity efficiency via activation of antigen-presenting cells to stimulate the production of tumor-specific effector T cells in metastatic tumors. This TAM-membrane-based photodynamic immunotherapy approach offers a new strategy for personalized tumor therapy.

General Propagation Lattice Boltzmann Model for the Boussinesq Equation.

A general propagation lattice Boltzmann model is used to solve Boussinesq equations. Different local equilibrium distribution functions are selected, and the macroscopic equation is recovered with second order accuracy by means of the Chapman-Enskog multi-scale analysis and the Taylor expansion technique. To verify the effectiveness of the present model, some Boussinesq equations with initial boundary value problems are simulated. It is shown that our model can remain stable and accurate, which is an effective algorithm worthy of promotion and application.