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Abstract The artificial photocatalytic synthesis based on graphitic carbon nitride (g-C3N4) for H2O2 production is evolving rapidly. However, the simultaneous production of high-value products at electron and hole sites remains a great challenge. Here, we use transformable potassium iodide to obtain semi-crystalline g-C3N4 integrated with the I-/I3 - redox shuttle mediators for efficient generation of H2O2 and benzaldehyde. The system demonstrates a prominent catalytic efficiency, with a benzaldehyde yield of 0.78 mol g−1 h−1 and an H2O2 yield of 62.52 mmol g−1 h−1. Such a constructed system can achieve an impressive 96.25% catalytic selectivity for 2e- oxygen reduction, surpassing previously reported systems. The mechanism study reveals that the strong crystal electric field from iodized salt enhances photo-generated charge carrier separation. The I-/I3 - redox mediators significantly boost charge migration and continuous electron and proton supply for dual-channel catalytic synthesis. This groundbreaking work in photocatalytic co-production opens neoteric avenues for high-value synthesis.

Abstract Artificial photosynthesis using carbon nitride (g-C3N4) holds a great promise for sustainable and cost-effective H2O2 production, but the high carrier recombination rate impedes its efficiency. To tackle this challenge, we propose an innovative method involving multispecies iodine mediators (I−/I3 −) intercalation through a pre-photo-oxidation process using potassium iodide (suspected deteriorated “KI”) within the g-C3N4 framework. Moreover, we introduce an external electric field by incorporating cationic methyl viologen ions to establish an auxiliary electron transfer channel. Such a unique design drastically improves the separation of photo-generated carriers, achieving an impressive H2O2 production rate of 46.40 mmol g−1 h−1 under visible light irradiation, surpassing the most visible-light H2O2-producing systems. Combining various advanced characterization techniques elucidates the inner photocatalytic mechanism, and the application potential of this photocatalytic system is validated with various simulation scenarios. This work presents a significative strategy for preparing and applying highly efficient g-C3N4-based catalysts in photochemical H2O2 production.

Abstract Carbazole derivatives can be used as antioxidants in the lubricating oil industry. The alkylation of carbazole with 2-chloro-2-methylpropane and 2-bromopropane catalyzed by anhydrous aluminum chloride was studied. Initially, 3,6-di-iso-propylcarbazole and 3,6-di-tert-butylcarbazole were using dichloromethane and dibromomethane as solvents at room temperature, respectively. The synthesis conditions were optimized. Subsequently, the effects of reaction time, catalyst dosage, and molar ratio of carbazole to alkylating agent were investigated, and orthogonal experiments were performed. The structures of the carbazole derivatives were characterized by Fourier infrared spectroscopy (FT-IR), mass spectrum (MS) and nuclear magnetic resonance spectroscopy (NMR). The thermal stability of the synthesized carbazole derivatives was investigated by differential scanning calorimetry (DSC). The carbazole derivatives were added into the lubricating oil with a mass fraction of 0.8% and the miscibility, stability and oxidation resistance of the mixed system were evaluated by mechanical stirring and a rotary pressure vessel oxidation test (RPVOT). The DSC results showed that there was good thermal stability for the carbazole derivatives. The mechanical stirring method revealed good solubility and stability for the mixture of oil and carbazole derivatives. The RPVOT results showed that isopropyl carbazole derivatives could increase the oxidation induction period of lubricating oil to 1.39 times, and tert-butyl carbazole derivatives could increase the oxidation induction period of lubricating oil to 1.91 times. The antioxidant effect of tert-butyl carbazole derivatives was better than that of isopropyl carbazole derivatives.

The addition of certain amounts of Mn in steel has long been known to retard the growth and coarsening of cementite during tempering, which can increase the tempering resistance of carbon steels. It is now well-established that the retarding effect is inherently correlated with the partitioning of Mn between ferrite (α) matrix and cementite (θ). According to the equilibrium thermodynamics, Mn would diffuse from α-Fe matrix to θ cementite after the initial stage of tempering until equilibrium is reached. However, the manner in which Mn diffuses from α-Fe matrix to θ cementite is unclear, which is key in understanding the mechanism in which the partitioning of Mn can retard the growth and coarsening of cementite. Therefore, the measurement of Mn content across the α-Fe/θ interface is of importance to achieve this goal. In this study, the redistribution characteristics of Mn between α-Fe matrix and θ cementite after long-term aging at 370 or 400 °C with quenched–tempered or quenched samples of reactor pressure vessel model steel was investigated by atom probe tomography. Results show that Mn diffuses from the α-Fe matrix and enriches in the θ cementite under all heat treatment conditions. The concentration of Mn in cementite is the highest when the specimen is thermally aged directly after quenching. Moreover, Mn is not distributed uniformly within cementite after long-term aging at 400 °C for 35000 h. Instead, a Mn-segregated zone exists within cementite adjacent to the α-Fe/θ interface, with concentration increasing by aging temperature, which acts as a barrier to the coarsening of cementite by hindering the dissolution of small-sized cementite. The redistribution characteristics of Mn between the two phases is correlated with the difference of diffusivities in the α-Fe matrix and θ cementite during thermal aging, and the diffusivity of Mn in θ cementite is slower than that in α-Fe matrix.

Background: The safety and efficacy of neoadjuvant immunochemotherapy (nICT) for locally advanced gastric cancer (LAGC) remain controversial. Methods: Patients with LAGC who received either nICT or neoadjuvant chemotherapy (nCT) at 3 tertiary referral teaching hospitals in China between January 2016 and October 2022 were analyzed. After propensity-score matching (PSM), comparing the radiological response, pathological response rate, perioperative outcomes, and early recurrence between the two groups. Results: After PSM, 585 patients were included, with 195 and 390 patients comprising the nICT and nCT groups, respectively. The nICT group exhibited a higher objective response rate (79.5% vs. 59.0%; P<0.001), pathological complete response rate (14.36% vs. 6.41%; P=0.002) and major pathological response rate (39.49% vs. 26.15%; P =0.001) compared with the nCT group. The incidence of surgical complications (17.44% vs. 16.15%, P =0.694) and the proportion of perioperative textbook outcomes (80.0% vs. 81.0%; P= 0.767) were similar in both groups. The nICT group had a significantly lower proportion of early recurrence than the nCT group (29.7% vs. 40.8%; P =0.047). Furthermore, the multivariable logistic analysis revealed that immunotherapy was an independent protective factor against early recurrence [odds ratio 0.62 (95% CI 0.41-0.92); P= 0.018]. No significant difference was found in neoadjuvant therapy drug toxicity between the two groups (51.79% vs. 45.38%; P= 0.143). Conclusions: Compared with nCT, nICT is safe and effective, which significantly enhanced objective and pathological response rates and reduced the risk for early recurrence among patients with LAGC. Trial registration: Clinical Trials.gov. [ABSTRACT FROM AUTHOR]

Background: Robotic gastrectomy is a safe and feasible approach for gastric cancer (GC); however, its long-term oncological efficacy remains unclear. The authors evaluated the long-term survival outcomes and recurrence patterns of patients with locally advanced proximal GC who underwent robotic total gastrectomy (RTG). Methods: This prospective study (FUGES-014 study) enrolled 48 patients with locally advanced proximal GC who underwent RTG between March 2018 and February 2020 at a tertiary referral teaching hospital. Patients who underwent laparoscopic total gastrectomy (LTG) in the FUGES-002 study were enrolled in a 2:1 ratio to compare the survival outcomes between RTG and LTG. The primary endpoint of the FUGES-014 study was postoperative 30-day morbidity and has been previously reported. Here, the authors reported the results of 3-year disease-free survival (DFS), 3-year overall survival (OS), and recurrence patterns. Results: After propensity score matching, 48 patients in the RTG and 96 patients in the LTG groups were included. The 3-year DFS rates were 77.1% (95% CI: 66.1-89.9%) for the RTG and 68.8% (95% CI: 60.1-78.7%) for the LTG groups (P = 0.261). The 3-year OS rates were not significantly different between the groups (85.4 vs. 74.0%, P = 0.122). Recurrence occurred in nine patients (18.8%) in the RTG and 27 (28.1%) patients in the LTG groups (P = 0.234). Recurrence patterns and causes of death were similar between the groups (P > 0.05). Conclusions: The oncological outcome of RTG was noninferior to that of LTG. Thus, RTG might be an alternative surgical treatment for locally advanced proximal GC. [ABSTRACT FROM AUTHOR]

Background: The results of several large randomized controlled trials (RCTs) have changed the clinical practice of bariatric surgery. However, the characteristics of global RCTs of bariatric surgery have not been reported internationally and whether there was research waste in these RCTs is unknown. Methods: Search ClinicalTrials.gov for bariatric surgery RCTs registered between January 2000 and December 2022 with the keywords 'Roux-en-Y gastric-bypass' and 'Sleeve Gastrectomy'. The above analysis was conducted in January 2023. Results: A total of 326 RCTs were included in this study. The number of RCTs registered for sleeve gastrectomy and gastric bypass surgery increased year by year globally. Europe has always accounted for the largest proportion, Asia has gradually increased, and North America has decreased. A total of 171 RCTs were included in the analysis of waste, of which 74 (43.8%) were published. Of the 74 published RCTs, 37 (37/74, 50.0%) were judged to be adequately reported and 36 (36/74, 48.6%) were judged to have avoidable design defects. In the end, 143 RCTs (143/171, 83.6%) had at least one research waste. Body weight change as the primary endpoint (OR: 0.266, 95% CI: 0.103-0.687, P=0.006) and enrolment greater than 100 (OR: 0.349, 95% CI: 0.146-0.832, P=0.018) were independent protective factors for research waste. Conclusions: This study for the first time describes the characteristic changes of the mainstream RCT of bariatric surgery globally in the last 20 years and identifies a high research waste burden and predictive factor in this area, which provides reference evidence for carrying out bariatric surgery RCTs more rationally. [ABSTRACT FROM AUTHOR]

In our quest to leverage the capabilities of the emerging single-atom catalysts (SACs) for wastewater purification, we confronted fundamental challenges related to electron scarcity and instability. Through meticulous theoretical calculations, we identified optimal placements for nitrogen vacancies (Nv) and iron (Fe) single-atom sites, uncovering a dual-site approach that significantly amplified visible-light absorption and charge transfer dynamics. Informed by these computational insights, we cleverly integrated Nv into the catalyst design to boost electron density around iron atoms, yielding a potent and flexible photoactivator for benign peracetic acid. This exceptional catalyst exhibited remarkable stability and effectively degraded various organic contaminants over 20 cycles with self-cleaning properties. Specifically, the Nv sites captured electrons, enabling their swift transfer to adjacent Fe sites under visible light irradiation. This mechanism accelerated the reduction of the formed "peracetic acid-catalyst" intermediate. Theoretical calculations were used to elucidate the synergistic interplay of dual mechanisms, illuminating increased adsorption and activation of reactive molecules. Furthermore, electron reduction pathways on the conduction band were elaborately explored, unveiling the production of reactive species that enhanced photocatalytic processes. A six-flux model and associated parameters were also applied to precisely optimize the photocatalytic process, providing invaluable insights for future photocata- lyst design. Overall, this study offers a molecule-level insight into the rational design of robust SACs in a photo-Fenton-like system, with promising implications for wastewater treatment and other high-value applications. [ABSTRACT FROM AUTHOR]

A second xylanase (APX-II) from the fungus Aureobasidium pullulans Y-2311-1 is purified and characterized, and shows increased activity towards birchwood xylan. It can therefore be used in biotechnological applications. The enzyme has high pI value of 9.4 and a low apparent mass of 25 kDa. The isoenzymes, APX-I and APX-II, are in close association, although major variations in amino acid composition reveals that two different genes encode them.