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Covalent organic frameworks (COFs) have emerged as promising platforms for the construction of single-atom and dual-atom catalysts (SACs and DACs), owing to their well-defined structures, tunable pore sizes, and abundant active sites. In recent years, the development of COF-based SACs and DACs as highly efficient catalysts has witnessed a remarkable surge. The synergistic interplay between the metal active sites and the COF has established the design and fabrication of COF-based SACs and DACs as a prominent research area in electrocatalysis. These catalytic materials exhibit promising prospects for applications in energy storage and conversion devices. This review summarizes recent advances in the design, synthesis, and applications of COF-based SACs and DACs for oxygen catalysis. The catalytic mechanisms of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are comprehensively explored, providing a comparative analysis to elucidate the correlation between the structure and performance, as well as their functional attributes in battery devices. This review highlights a promising approach for future research, emphasizing the necessity of rational design, breakthroughs, and in-situ characterization to further advance the development of high-performance COF-based SACs and DACs for sustainable energy applications. [ABSTRACT FROM AUTHOR]

To achieve the actual situation of water pressure stabilization during underground and tunnel water inrush disasters, the team independently developed a stable water pressure test system and conducted fracture and failure tests on fissured rock masses under the coupling effect of 1MPa stable water pressure and stress and without water pressure. Combined with data collected by acoustic emission instruments, the mechanical characteristics of fracture and failure, crack propagation mechanism, and acoustic emission response mechanism of fissured rock masses under the coupling effect of stable hydraulic pressure and stress were studied. The results showed that throughout the entire experimental process, the hydraulic pressure remained continuously stable, with a decrease of only 0.14%; The variation pattern of peak strength of fissured rock mass with increasing crack inclination angle under stable hydraulic pressure changes from a decrease and then an increase in the absence of hydraulic pressure to an increasing trend; The crack propagation length of low angle fissured rock mass is generally higher than that of high angle fissured specimens. The longer propagation path increases the range and effect of hydraulic pressure, and the initial crack propagation length of fissured rock mass under hydraulic pressure is also significantly longer than that of specimens without hydraulic pressure; During the loading process, both the acoustic emission ringing count and damage variable can be divided into four stages. From the cumulative total number of acoustic emission ringing counts, it can be seen that during the loading process, the total number of acoustic emission ringing in fissured rock masses subjected to hydraulic pressure is significantly lower than that of specimens without hydraulic pressure, and the trend is also relatively stable. [ABSTRACT FROM AUTHOR]

Collaborative conversion of methane and carbon dioxide into sustainable chemicals is an appealing solution to simultaneously overcome both environmental problems and energy crisis. However, this reaction is limited to the preparation of syngas with the unfavorable feature for transportation and storage. Herein, liquid formaldehyde as product is fabricated by the collaborative conversion of methane and carbon dioxide using anatase phase titanium dioxide as photocatalyst. The productivity reaches 14.65 mmol g−1 with 88.32% selectivity. In situ diffuse reflectance Fourier transform infrared spectroscopy, isotope testes, and theoretical calculation clarify that the photoexcited holes and electrons engage into methane oxidation and carbon dioxide reduction over anatase using surface hydroxyl species and oxygen vacancy as active sites, respectively. The consumption of surface hydroxyl species on methane oxidation promotes the oxygen vacancy formation for carbon dioxide adsorption, mutually the carbon dioxide provides the oxygen atom for surface hydroxyl species facilitating methane oxidation. The consumption of photoelectrons and photoholes on carbon dioxide reduction and methane oxidation balances the number of photogenerated carriers and ensures the catalytic system stability. In this work, the avenue is broadened toward the co‐conversion of greenhouse gas into desirable chemical products in a sustainable way. [ABSTRACT FROM AUTHOR]

Objective: Early articular cartilage lesion (CL) is a vital sign in the onset of posttraumatic knee osteoarthritis (PTOA) in patients with anterior cruciate ligament deficiency (ACLD). Researchers have suggested that altered kinematics could accelerate CLs and, therefore, lead to the onset of PTOA. However, little is known about whether specific knee kinematics exist that lead to early CL in chronic ACLD knees. Level walking is the most frequent and relevant in vivo activity, which greatly impacts knee health. We hypothesized that the knee kinematics during level walking in chronic ACLD knees with early tibiofemoral CL would significantly differ from those of chronic ACLD knees without early tibiofemoral CL. Methods: Thirty patients with a chronic ACLD history, including 18 subjects with CLs and 12 subjects without CLs, and 35 healthy control subjects were recruited for the study from July 2020 to August 2022. The knee kinematic data during level walking were collected using a three‐dimensional motion analysis system. The kinematic differences between groups were compared using statistical parametric mapping with one dimension for One‐Way ANOVA. The cartilage statuses of the ACLD knees were assessed via MRI examination. The CLs distribution of subjects was evaluated using a modified Noyes scale and analyzed by chi‐square tests. Results: ACLD knees with CLs had significantly greater posterior tibial translation (7.7–8.0mm, 12%–18% gait cycle GC, p = 0.014) compared to ACLD knees without CLs during level walking. ACLD knees with CLs had greater posterior tibial translation (4.6–5.5mm, 0%–23% GC, p < 0.001; 5.8–8.0mm, 86%–100% GC, p < 0.001) than healthy controls during level walking. In the group of ACLD knees with CLs, CL is mainly located in the back of the tibia plateau and front of load bearing area of the medial femoral condyle (p < 0.05). Conclusion: Chronic anterior cruciate ligament deficient knees with cartilage lesions have increased posterior tibial translation compared to anterior cruciate ligament deficient knees without cartilage lesions and healthy subjects. The posterior tibial translation may play an important role in knee cartilage degeneration in ACLD knees. The increased posterior tibial translation and cartilage lesion characteristics may improve our understanding of the role of knee kinematics in cartilage degeneration and could be a helpful potential reference for anterior cruciate ligament deficient therapy, such as physical training to improve abnormal kinematic behavior. [ABSTRACT FROM AUTHOR]

The study explored the influence of both conventional MIL-101 and amino-functionalized MIL-101 on the adsorption performance of volatile organic compounds (e.g., benzene, toluene, and p-xylene) was investigated through computational chemistry techniques (Gaussian, Materials Studio, and Grand Canonical Monte Carlo). The results reveal that the MIL-101-NH2benzene, toluene, and p-xylene but also significantly enhance their adsorption capacity at low pressures. [ABSTRACT FROM AUTHOR]

An efficient heterogeneous gold-catalyzed Sandmeyer coupling of aryldiazonium salts with sodium bromide or thiols for the formation of C–Br and C–S bonds has been achieved in high yields and selectivities under mild conditions by using a bis(diphenylphosphinomethyl)amino-modified mesoporous MCM-41-immobilized gold(I) chloride complex [MCM-41-2Ph2PAuCl] as the catalyst without using sacrificial oxidants. Vital to the success of this C-heteroatom coupling is the nucleophile-promoted activation of aryldiazonium salts, which can serve as an efficient oxidant for the conversion of Au(I) to Au(III) without the use of a photocatalyst or an assisting ligand. This new heterogenized gold(I) complex can be easily prepared by a simple procedure and recovered via centrifugation, and recycled more than seven times without any significant loss of its catalytic efficiency. [ABSTRACT FROM AUTHOR]

Background: Piperacillin is one of the most common drugs that cause drug-induced immune hemolytic anemia, but a complete description of the serological features and course of the disease is rare. This study completely describes the serological characteristics and course of a patient with hypertensive nephropathy who developed drug-induced immune hemolytic anemia and worsened renal function during repeated administration of piperacillin-tazobactam. Case presentation: A 79-year-old male patient with hypertensive nephropathy who developed severe hemolytic anemia and worsened renal function during intravenous piperacillin-tazobactam anti-infective treatment due to lung infection. Serological tests showed that the result of the direct antiglobulin test for anti-IgG was positive (4 +) and anti-C3d was negative, and the irregular red blood cell antibody screening test was negative. Plasma samples collected at different times from 2 days before to 12 days after the discontinuation of piperacillin-tazobactam administration were incubated with piperacillin solution and red blood cells of O-type healthy blood donors at 37 °C, IgG piperacillin-dependent antibodies were detected, and the highest titer was 128. However, no tazobactam-dependent antibody was detected in any plasma samples. Therefore, the patient was diagnosed with piperacillin-induced immune hemolytic anemia. Although blood transfusion and continuous renal replacement therapy were given, the patient died of multiple organ failure 15 days after the administration of piperacillin-tazobactam was stopped. Conclusion: This is the first complete description of the disease course and serological changes of piperacillin-induced immune hemolytic anemia, which is bound to help deepen the understanding of drug-induced immune hemolytic anemia and draw profound lessons from it. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the integrated efficacy of completely simultaneous ultrasonic scaling and subgingival irrigation with chlorhexidine in chronic periodontitis., Method and Materials: This was a split-mouth randomized controlled trial including 19 patients with moderate to severe chronic periodontitis. After calculus removal, the test side received simultaneous ultrasonic scaling and subgingival irrigation with 0.12% chlorhexidine, and the control side received simultaneous ultrasonic scaling and subgingival irrigation with distilled water. A newly designed ultrasonic scaler tip with a liquid outlet on the terminal was used. Clinical parameters were assessed, and gingival crevicular fluid was collected before treatment at baseline and 1.5, 3, and 6 months after baseline., Results: On follow-up, both sides showed significant reductions in clinical parameters and concentration of inflammatory mediators in gingival crevicular fluid. Adjunct application of CHX resulted in an additional periodontal pocket reduction (0.27 to 0.29 mm, P < .05) compared to the control side, in sites with initial probing depth of 4 to 5 mm. Within the initial probing depth ≥ 6 mm, the additional probing depth reduction was 0.44 to 0.60 mm (P < .05), with clinical attachment loss, concentration of interleukin-6, and concentration of matrix metalloproteinase-8 being 0.32 to 0.38 mm, 2.64 to 3.40 µg/L, and 19.78 to 22.39 ng/L, respectively (all P < .05)., Conclusion: In this study, treatment outcomes of chronic periodontitis could be improved by treating the root surface with simultaneous ultrasonic scaling and chlorhexidine irrigation. The adjunctive use of 0.12% chlorhexidine with a newly designed ultrasonic scaler tip in the treatment of moderate to severe chronic periodontitis demonstrated significant clinical benefits and decrease in inflammatory mediator when compared with scaling and root planing plus placebo.