Nonmetallic-Bonding Fe-Mn Diatomic Pairs Anchored on Hollow Carbonaceous Nanodisks for High-Performance Li-S Battery.

The issues of polysulfide shuttling and lethargic sulfur redox reaction (SROR) kinetics are the toughest obstacles of lithium-sulfur (Li-S) battery. Herein, integrating the merits of increased density of metal sites and synergistic catalytic effect, a unique single-atom catalyst (SAC) with nonmetallic-bonding Fe-Mn diatomic pairs anchored on hollow nitrogen-doped carbonaceous nanodisk (denoted as FeMnDA@NC) is successfully constructed and well characterized by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy, X-ray absorption spectroscopy, etc. Density functional theory calculation indicates that the Fe-Mn diatomic pairs can effectively inhibit the shuttle effect by enhancing the adsorption ability retarding the polysulfide migration and accelerate the SROR kinetics. As a result, the Li-S battery assembled with FeMnDA@NC modified separator possesses an excellent electrochemical performance with ultrahigh specific capacities of 1419 mAh g-1 at 0.1 C and 885 mAh g-1 at 3.0 C, respectively. An outstanding specific capacity of 1165 mAh g-1 is achieved at 1.0 C and maintains at 731 mAh g-1 after 700 cycles. Notably, the assembled Li-S battery with a high sulfur loading of 5.35 mg cm-2 harvests a practical areal capacity of 5.70 mAh cm-2 at 0.2 C. A new perspective is offered here to construct advanced SACs suitable for the Li-S battery.

LiF-Rich Alloy-Doped SEI Enabling Ultra-Stable and High-Rate Li Metal Anode.

Li metal is regarded as the "Holy Grail" in the next generation of anode materials due to its high theoretical capacity and low redox potential. However, sluggish Li ions interfacial transport kinetics and uncontrollable Li dendrites growth limit practical application of the energy storage system in high-power device. Herein, separators are modified by the addition of a coating, which spontaneously grafts onto the Li anode interface for in situ lithiation. The resultant alloy possessing of strong electron-donating property promotes the decomposition of lithium bistrifluoromethane sulfonimide in the electrolyte to form a LiF-rich alloy-doped solid electrolyte interface (SEI) layer. High ionic alloy solid solution diffusivity and electric field dispersion modulation accelerate Li ions transport and uniform stripping/plating, resulting in a high-power dendrite-free Li metal anode interface. Surprisingly, the formulated SEI layer achieves an ultra-long cycle life of over 8000 h (20,000 cycles) for symmetric cells at a current density of 10 mA cm-2. It also ensures that the NCM(811)//PP@Au//Li full cell at ultra-high currents (40 C) completes the charging/discharging process in only 68 s to provide high capacity of 151 mAh g-1. The results confirm that this scalable strategy has great development potential in realizing high power dendrite-free Li metal anode.

A Transmetalation Synthetic Strategy to Engineer Atomically Dispersed MnN2 O2 Electrocatalytic Centers Driving High-Performance LiS Battery.

Sluggish sulfur redox reaction (SROR) kinetics accompanying lithium polysulfides (LiPSs) shuttle effect becomes a stumbling block for commercial application of LiS battery. High-efficient single atom catalysts (SACs) are desired to improve the SROR conversion capability; however, the sparse active sites as well as partial sites encapsulated in bulk-phase are fatal to the catalytic performance. Herein, high loading (5.02 wt.%) atomically dispersed manganese sites (MnSA) on hollow nitrogen-doped carbonaceous support (HNC) are realized for the MnSA@HNC SAC by a facile transmetalation synthetic strategy. The thin-walled hollow structure (≈12 nm) anchoring the unique trans-MnN2 O2 sites of MnSA@HNC provides a shuttle buffer zone and catalytic conversion site for LiPSs. Both electrochemical measurement and theoretical calculation indicate that the MnSA@HNC with abundant trans-MnN2 O2 sites have extremely high bidirectional SROR catalytic activity. The assembled LiS battery based on the MnSA@HNC modified separator can deliver a large specific capacity of 1422 mAh g-1 at 0.1 C and stable cycling over 1400 cycles with an ultralow decay rate of 0.033% per cycle at 1 C. More impressively, a flexible pouch cell on account of the MnSA@HNC modified separator may release a high initial specific capacity of 1192 mAh g-1 at 0.1 C and uninterruptedly work after the bending-unbending processes.

Superior capsular reconstruction using the long head of the biceps to treat massive rotator cuff tears improves patients shoulder pain, mobility and function.

PURPOSE: Arthroscopic superior capsule reconstruction (SCR) with the long head of the biceps (LHBT) was performed to restore structural stability, force couple balance, and shoulder joint function. This study aimed to evaluate the functional outcomes of SCR using the LHBT over at least 24 months of follow-up. METHOD: This retrospective study included 89 patients with massive rotator cuff tears who underwent SCR using the LHBT, met the inclusion criteria and underwent follow up for at least 24 months. The preoperative and postoperative shoulder range of motion (forward flexion, external rotation, and abduction), acromiohumeral interval (AHI), visual analog scale (VAS) score, American Shoulder and Elbow Surgeons (ASES) score and Constant-Murley score were obtained, and the tear size, and Goutallier and Hamada grades were also investigated. RESULTS: Compared with those measured preoperatively, the range of motion, AHI, and VAS, Constant-Murley, and ASES scores were significantly improved immediately postoperatively (P < 0.001) and at the 6-month, 12-month, and final follow-ups (P < 0.001). At the last follow-up, the postoperative ASES score and Constant-Murley score increased from 42.8 ± 7.6 to 87.4 ± 6.1, and 42.3 ± 8.9 to 84.9 ± 10.7, respectively; with improvements of 51 ± 21.7 in forward flexion, 21.0 ± 8.1 in external rotation, and 58.5 ± 22.5 in abduction. The AHI increased 2.1 ± 0.8 mm and the VAS score significantly changed from 6.0 (5.0, 7.0) to 1.0 (0.0, 1.0), at the final follow-up. Eleven of the 89 patients experienced retears, and one patient needed reoperation. CONCLUSION: In this study with at least 24-months of follow-up, SCR using the LHBT for massive rotator cuff tears could effectively relieve shoulder pain, restore shoulder function and increase shoulder mobility to some extent. LEVEL OF EVIDENCE: IV.

Dual-Atom Nickel Moieties of Ni(II)2 N4 (µ2 -N)2 Anchored on Alfalfa-Derived Developed Porous N-Doped Carbon for High-Performance Li-S Battery.

A universal strategy is established for preparing the carbonaceous matrix-based atomically distributed metal catalysts M-BPC (M=Ni, Co, Fe, Cu, and Mn, and biomass-derived porous carbon (BPC)) by one-step pyrolysis of mixed metal salts and biomass alfalfa. The optimized Ni-BPC has dual-atom Ni(II)2 N4 (µ2 -N)2 moieties, which are chemically anchored on the alfalfa-derived developed porous N-doped carbon BPC matrix. An ultrahigh specific surface area of 3133 m2 g-1 with huge total pore volume of 3.02 cm3 g-1 is obtained for Ni-BPC. The Ni-BPC could greatly promote the redox kinetics and effectively prevent the shuttle effect of lithium polysulfides in a Li-S battery. The Li-S battery assembled with the Ni-BPC modified separator exhibits prominent rate performance with the reversible specific capacities of 1279, 1119, 1037, 948 and 787 mAh g-1 at the current densities of 0.1, 0.2, 0.5, 1 and 2 C, respectively. The battery presents an ultra-long life with low capacity decay of 0.028% per cycle up to 2100 cycles at 1 C. Even under high areal S loadings of 3.9 mg cm-2 , the high discharge capacity of 976.6 mAh g-1 is obtained at 0.2 C and excellent cycling stability with 61.1% capacity retention is achieved after 490 cycles.

Effects of hypoxia environment on osteonecrosis of the femoral head in Sprague-Dawley rats.

INTRODUCTION: Osteonecrosis of the femoral head (ONFH) is a disease in which the blood supply of the femoral head is interrupted or damaged, resulting in joint dysfunction. Hypoxic environments increase the expression of EPO, VEGF, and HIF causes vascular proliferation and increases the blood supply. It also causes the organism to be in a state of hypercoagulability and increases thrombosis. Therefore, the purpose of this study was to explore the occurrence of ONFH after the use of glucocorticoids (GCs) under conditions of hypoxia tolerance for a long time. MATERIALS AND METHODS: Sprague-Dawley rats were fed in a hypobaric hypoxic chamber at an altitude of 4000 m, the whole blood viscosity, and plasma viscosity were determined to analyze the blood flow and hemagglutination. Western blotting, polymerase chain reaction, and immunohistochemistry were used to detect EPO, VEGF, CD31, and osteogenesis related proteins. Femoral head angiography was used to examine the local blood supply and micro-CT scanning was used to detect the structure of the bone trabecula. RESULTS: Under hypoxic environments, the expression of EPO and VEGF increased, which increased the local blood supply of the femoral head, but due to more severe thrombosis, the local blood supply of the femoral head decreased. CONCLUSIONS: Hypoxic environments can aggravate ONFH in SD rats; this aggravation may be related to the hypercoagulable state of the blood. We suggest that long-term hypoxia should be regarded as one of the risk factors of ONFH and we need to conduct a more extensive epidemiological investigation on the occurrence of ONFH in hypoxic populations.

[Effect of exogenous L-arginie on survival of extended dorsal perforator flaps in rats].

Objective: To investigate the effect of exogenous L-Arg on the survival of extended perforator flap in rats. Methods: Sixteen male Sprague Dawley rats were randomly divided into L-Arg group (n=8) and control group(n=8). The extended dorsal three-vascular territory perforator flaps were made in rats. L-Arg (400 mg·kg-1·d-1) was injected intraperitoneally in L-Arg group 1d before operation, immediately and 1-7 d after operation, while the same volume of saline was injected intraperitoneally in control group at the same time points. The appearance and distribution of blood vessels were observed, and the flap survival areas were measured 7d after operation. The tissue samples were harvested from choke zone Ⅱ for histological study and the expression of vascular endothelial growth factor (VEGF) was detected by immunohistochemistry and Western blot, respectively. Results: After 7d, the clearer vascular structure and more new vessels in choke zone Ⅱ were observed in L-Arg group. The survival rate of flap in L-Arg group was (88.42±4.19)%, which was significantly higher than that in control group[(76.52±5.37)%, t=3.707, P<0.01]. The microvessel density and caliber of choke zone Ⅱ in L-Arg group was (29.47±5.28)/mm2 and(47.27±5.32)µm, which were significantly higher than those in control group (t=2.694 and 2.389, P<0.05 or P<0.01). The immunohistochemistry and Western blot showed that the expression of VEGF in choke zone Ⅱ of L-Arg group was significantly higher than that in control group (t=9.428 and -3.054,P<0.05 or P<0.01). Conclusion: Exogenous L-Arg can increase the survival rate of extended dorsal perforator skin flap through promoting vascularization and dilatation of vessels in choke zone Ⅱ in rats.

Biomass-Derived Porous Carbon with Micropores and Small Mesopores for High-Performance Lithium-Sulfur Batteries.

Biomass-derived porous carbon BPC-700, incorporating micropores and small mesopores, was prepared through pyrolysis of banana peel followed by activation with KOH. A high specific BET surface area (2741 m2 g-1 ), large specific pore volume (1.23 cm3 g-1 ), and well-controlled pore size distribution (0.6-5.0 nm) were obtained and up to 65 wt % sulfur content could be loaded into the pores of the BPC-700 sample. When the resultant C/S composite, BPC-700-S65, was used as the cathode of a Li-S battery, a large initial discharge capacity (ca. 1200 mAh g-1 ) was obtained, indicating a good sulfur utilization rate. An excellent discharge capacity (590 mAh g-1 ) was also achieved for BPC-700-S65 at the high current rate of 4 C (12.72 mA cm-2 ), showing its extremely high rate capability. A reversible capacity of about 570 mAh g-1 was achieved for BPC-700-S65 after 500 cycles at 1 C (3.18 mA cm-2 ), indicating an outstanding cycling stability.

[One-stage bone grafting combined with non-contact plate technique for treatment of post-traumatic femoral osteomyelitis and bone defects].

Eight patients with femoral osteomyelitis were admitted in Lanzhou General Hospital of PLA between July 2012 and July 2015. During the operation the femur was fixed with non-contact locking plate after thorough debridement. Iliac morselized cancellous bones without cortical bone were filled in the bone defect after debridement. The locking plates were placed in the lateral subcutaneous interface superficial to the vastus lateralis muscle. Drainage tubes were routinely placed postoperatively. The surgery was completed successfully in all patients, and the average operation time was (130±10) min (120-150 min). Intravenous antibiotics were administrated for 2 weeks and followed by 4 week-oral antibiotics after the operation in all 8 cases. Drainage tubes remained in situ about 8 days. All patients were followed up for 12-48 months, with an average of (19±7) months. Postoperative X-ray examination showed bone union in 7 cases with an average healing time of (16±5) weeks. One patient failed with relapsed infection, and was later treated with Ilizarov apparatus after secondary debridement. No plate and screw fracture, loose and fixation failure were observed in all 8 cases.

[Operative versus non-operative treatment for three- or four-part proximal humeral fractures in elderly patients: a meta-analysis of randomized controlled trials].

Objective: To evaluate the efficacy of operative and non-operative treatment for three- or four-part proximal humeral fractures in elderly patients by meta-analysis. Methods: The literature search was performed in Cochrance Library, Medline, Embase, SinoMed, CNKI, Wanfang data and CQVIP databases for operative and non-operative treatment of three- or four-part proximal humeral fractures in elderly patients, and searches of conference proceedings were also conducted. The data were extracted and a meta-analysis was performed using RevMan 5.3. The outcome measures included Constants score, pain and incidence rates of AVN, reoperation, osteoarthritis, nonunion. Results: Six randomized controlled trials involving 264 patients were included in the meta-analysis. The differences of Constant scores (MD=0.47, 95% CI:-4.35-5.28, P=0.85), incidence of ANV (OR=0.56, 95% CI:0.25-1.24, P=0.15), incidence of osteoarthritis (OR=0.56, 95% CI:0.19-1.68, P=0.30), incidence of nonunion (OR=0.43, 95% CI:0.13-1.43, P=0.17) between operative group and non-operative group were not statistically significant. Operative treatment was better in pain score (MD=1.01, 95% CI:0.12-1.19, P=0.03) and had statistically significant higher reoperative rate (OR=3.97, 95% CI:1.45-10.92, P=0.007). Conclusions: No evidence support that there is difference in Constant score and incidence rate of ANV, osteoarthritis, nonunion between operative and non-operative treatment for three- or four-part proximal humeral fractures in elderly patients. More high quality randomized controlled trials are required to determine which treatment is more efficient.

A novel means of capitate distraction lengthening for end-stage Kienböck's disease.

We present a patient with Kienböck's disease treated with a novel technique of capitate distraction lengthening using two wires in the proximal capitate and two in the ulna.

Eleven internal fixations for young vertical femoral neck fractures: A protocol for systematic review and network meta-analysis.

BACKGROUND AND OBJECTIVES: Vertical femoral neck fractures (VFNFs) in young patients lead to significant biomechanical instability. Multitudinous internal fixation devices have been developed and utilized in clinical interventions. However, there has yet to be a consensus expert opinion regarding the optimal internal fixation configurations. This study aims to conduct a network meta-analysis to evaluate the safety and efficacy of all currently recognized internal fixation procedures for the treatment of VFNFs in young individuals. METHODS: Comprehensive literature searches will be performed in China National Knowledge Infrastructure, the Cochrane Library, PubMed, Web of Science, Embase, the Wanfang Database, and the Chinese Biomedical Literature Database, covering the entire database history up until May 21, 2024. Individual papers will be evaluated for possible bias using RoB 2.0, the most recent version of the randomized trial Cochrane risk-of-bias approach. Pairwise meta-analysis and network meta-analysis (NMA) will be conducted for data analysis using STATA 15.0 and R 4.1.3. Inconsistency tests, subgroup analyses, sensitivity analyses, and assessments of publication bias will also be performed. CONCLUSION: The study will provide evidence-based recommendations for the optimal internal fixation methods in treating young patients with VFNFs. TRIAL REGISTRATION: INPLASY202460017.

Small money, big change: The distributional impact of differentiated doctor's visit fee on healthcare utilization.

A prominent issue in China's healthcare sector is the overcrowding of high-tier hospitals, whereas low-tier hospitals and community health centers are severely underutilized. This study aims to examine whether doctor's visit fee and copay differentiated by the level of healthcare providers can change the distribution of outpatient visits across different levels of healthcare providers. By leveraging the exogeneity of the policy change implemented in a megacity in China in 2017, we apply a parametric discontinuity regression model to study the causal impact of differentiated pricing on patients' health-seeking behavior, using a large-scale insurance claim database. We find that the reform of differentiated doctor's visit fee schedule effectively increases the proportion of visits to primary care facilities among all outpatient visits. This effect is driven by a decline in visits to the highest-tier hospitals and an increase in visits to community healthcare centers. Furthermore, the policy effects are more pronounced among the elderly and people with chronic diseases. Our results suggest that shifting the focus of pricing policies from coinsurance to copays while continuing to improve the capacity of primary care facilities is an effective way to facilitate triaging patients into different levels of care without triggering moral hazard.

Cyber-infrastructure and epidemic precautionary policy: evidence from China.

Introduction: The application of technology supported by cyber infrastructure has emerged as a critical factor influencing city management. This study aims to investigate whether the development of cyber infrastructure can enhance cities' confidence in responding to potential epidemic threats in the context of COVID-19. Methods: China serves as a good example for both COVID-19 management and smart city construction. We take advantage of a special time point, the 2022 Chinese New Year, to observe cities' precautionary epidemic policies. We utilize choice models and data from 188 Chinese cities to examine the impact of internet coverage on the degree of policy relaxation. Results: We found that cities with higher internet coverage tend to adopt looser policies. In the benchmark regression, for every 1 percentage point increase in internet coverage, the likelihood of implementing loose measures increases by 0.9 percentage points. This result remains robust across different classifications of policies. We also addressed potential endogeneity issues by using the instrumental variables method. Discussion: Our study indicates that effective management of epidemics in the modern era requires not only the utilization of traditional medical resources but also the incorporation of new city features, such as information technology infrastructure.

[Progress in antibacterial/osteogenesis dual-functional surface modification strategy of titanium-based implants].

Objective: To review antibacterial/osteogenesis dual-functional surface modification strategy of titanium-based implants, so as to provide reference for subsequent research. Methods: The related research literature on antibacterial/osteogenesis dual-functional surface modification strategy of titanium-based implants in recent years was reviewed, and the research progress was summarized based on different kinds of antibacterial substances and osteogenic active substances. Results: At present, the antibacterial/osteogenesis dual-functional surface modification strategy of titanium-based implants includes: ① Combined coating strategy of antibiotics and osteogenic active substances. It is characterized in that antibiotics can be directly released around titanium-based implants, which can improve the bioavailability of drugs and reduce systemic toxicity. ② Combined coating strategy of antimicrobial peptides and osteogenic active substances. The antibacterial peptides have a wide antibacterial spectrum, and bacteria are not easy to produce drug resistance to them. ③ Combined coating strategy of inorganic antibacterial agent and osteogenic active substances. Metal ions or metal nanoparticles antibacterial agents have broad-spectrum antibacterial properties and various antibacterial mechanisms, but their high-dose application usually has cytotoxicity, so they are often combined with substances that osteogenic activity to reduce or eliminate cytotoxicity. In addition, inorganic coatings such as silicon nitride, calcium silicate, and graphene also have good antibacterial and osteogenic properties. ④ Combined coating strategy of metal organic frameworks/osteogenic active substances. The high specific surface area and porosity of metal organic frameworks can effectively package and transport antibacterial substances and bioactive molecules. ⑤ Combined coating strategy of organic substances/osteogenic active substancecs. Quaternary ammonium compounds, polyethylene glycol, N-haloamine, and other organic compounds have good antibacterial properties, and are often combined with hydroxyapatite and other substances that osteogenic activity. Conclusion: The factors that affect the antibacterial and osteogenesis properties of titanium-based implants mainly include the structure and types of antibacterial substances, the structure and types of osteogenesis substances, and the coating process. At present, there is a lack of clinical verification of various strategies for antibacterial/osteogenesis dual-functional surface modification of titanium-based implants. The optimal combination, ratio, dose-effect mechanism, and corresponding coating preparation process of antibacterial substances and bone-active substances are needed to be constantly studied and improved.

A unique nanocomposite with FeCo nanoalloy anchored on S, N co-doped carbonaceous matrix for high bifunctional oxygen reduction reaction/oxygen evolution reaction electrocatalytic property in Zn-air battery.

A unique nanocomposite of FeCo-NSCC (means FeCo nanoalloy anchored on N, S co-doped carbonaceous composite) is obtained by one-pot pyrolysis using mixed natural wool fibers, dicyandiamide and the corresponding metal salts. The FeCo-NSCC has a higher degree of graphitization and a high specific surface area of 359 m2 g-1. The FeCo-NSCC exhibits a promising bifunctional oxygen reduction reaction/oxygen evolution reaction (OER/ORR) electrocatalytic activity with onset potential and half-wave potentials of 0.980 and 0.853 V vs reversible hydrogen electrode for ORR, and a low overpotential of 351 mV at 10 mA cm-2 for OER, superior to that of state-of-the-art commercial Pt/C and RuO2. The FeCo-NSCC presents a vigorous bifunctional OER/ORR electrocatalytic activities with the low ΔE(E1/2 - Ej=10) of 0.727 V, superior to most of the reported non-noble metal-based catalysts. Besides, the FeCo-NSCC shows remarkable durability and methanol resistance. The FeCo-NSCC based battery works at an open circuit voltage of 1.52 V and has a maximum power density of 161 mW cm-2 at current density of 246 mA cm-2, better than those of Pt/C-RuO2 based battery (1.47 V; 106 mW cm-2, 145 mA cm-2). The FeCo-NSCC based battery is stable with no obvious increased voltage gap after 60 h cycles.

Titanium elastic nails vs locking plate in pediatric subtrochanteric femur fractures: A systematic review and meta-analysis.

Objective: Titanium elastic nails (TENs) and locking plates (LPs) are currently the main internal fixation for treating pediatric subtrochanteric femur fractures, and the optimal choice of internal fixation is controversial. This study aimed to systematically evaluate the effectiveness and safety of TENs and LPs in treating subtrochanteric fractures in children to provide a theoretical basis and reference for clinical treatment. Methods: The literature related to TENs and LPs for treating subtrochanteric fractures in children was searched using the CNKI, PubMed, Cochrane, Embase, and Web of Science, and the search time frame was from the establishment of the database to October 2022. Two evaluators screened the literature according to the inclusion and exclusion criteria and extracted relevant data. Meta-analysis was performed using Stata14.0 software. Results: A total of 9 studies with 407 patients with subtrochanteric femur fractures were included in the final screening, including 210 cases with TENs and 197 cases with LPs. Meta-analysis results showed that compared with the locking plate, TEN had a shorter operative time [WMD = -1.3, 95%CI(-1.94,-0.66), p < 0.01], less intraoperative bleeding [WMD = -84.45, 95%CI(-111.09, -57.82), p < 0.01], shorter fracture healing time [WMD = -1.3, 95%CI(-1.94,-0.66), P < 0.01], shorter hospital stays [WMD = -2.80, 95% CI(-4.63,-0.98), p < 0.01], and earlier full weight bearing [SMD = -0.48, 95% CI(-0.91,-0.04), p < 0.05] but more intraoperative fluoroscopy [WMD = 28.23, 95% CI(15.22,41.25), p < 0.05]. The overall complication rate was high [OR = 3.52, 95% CI(1.96,6.34), p < 0.05], and the postoperative period was prone to angulation, rotation, and inversion deformity [OR = 3.68, 95% CI(1.40, 9.68), p < 0.05]. No significant difference in the incidence of lower limb inequality between the two types of internal fixation [OR = 0.83, 95% CI(0.38, 1.85), p > 0.05] and no significant difference in the Harris score of the hip at the last follow-up between the two types of internal fixation [WMD = -0.67, 95% CI(-2.01,0.67), p > 0.05] were found. Conclusion: In comparison to LPs, TENs have a shorter operation time, less intraoperative bleeding, and a shorter fracture healing time, and the child can be fully weight-bearing earlier. Locking plates can reduce the operator's x-ray exposure, and the incidence rate of postoperative angulation, rotation, and inversion deformity is low. Therefore, TENs and LPs are the best internal fixation methods for treating subtrochanteric fractures in children.

Enhancing Sulfur Redox Conversion of Active Iron Sites by Modulation of Electronic Density for Advanced Lithium-Sulfur Battery.

Despite lithium-sulfur (Li-S) batteries possessing ultrahigh energy density as great promising energy storage devices, the suppressing shuttle effect and improving sulfur redox reaction (SROR) are vital for their practical application. Developing high-activity electrocatalysts for enhancing the SROR kinetics is a major challenge for the application of Li-S batteries. Herein, single-molecule iron phthalocyanine species are anchored on the N and P dual-doped porous carbon nanosheets (Fe-NPPC) via axial Fe-N coordination to optimize the electronic structure of active centers. The Fe-NPPC can promote the catalytic conversion of polysulfides by modulation of the electronic density in active moieties, endowing the Li-S battery with a high reversible capacity of 1023 mAh g-1 at 1 C as well as an ultralow capacity decay of 0.035% per cycle over 1500 cycles. Even with a high sulfur loading of 7.1 mg cm-2 , the Li-S battery delivers a high areal capacity of 4.8 mAh cm-2 after 150 cycles at 0.2 C. With further increasing the sulfur loading to 9.2 mg cm-2 , an excellent areal capacity of up to 9.3 mAh cm-2 is obtained at 0.1 C.

[Analysis of the effectiveness of sequential plate internal fixation in correction of Madelung deformity after ulnar osteotomy and shortening].

Objective: To investigate the effectiveness of sequential plate internal fixation in the correction of Madelung deformity after ulnar osteotomy and shortening. Methods: The clinical data of 13 patients with Madelung deformity admitted between September 2015 and July 2021 were retrospectively analyzed. There were 5 males and 8 females with an average age of 18.3 years ranging from 17 to 23 years. The disease duration ranged from 12 to 24 months, with an average of 17 months. Three cases had a clear history of trauma. All patients had external radial deviation deformity and limited movement of the ulnar deviation, and the ulnar impact pain was significant during ulnar deviation movement; 9 patients had limited wrist joint supination movement, and the supination movement was normal. In the first stage, ulnar osteotomy and shortening combined with external fixator were used to correct wrist deformity in 13 patients. After operation, bone transfer was performed 6 times per day, with adjustments made every 4 hours, which was 1 mm per day. After the osteotomy was in place, the ulnar plate internal fixation was performed to reconstruct the ulnar stability in the second stage. The Cooney wrist joint score was used to assess the pain, function, range of motion, flexion and extension range of motion, and grip strength of the wrist joint before operation and before the removal of internal fixator. The subjective feeling and appearance satisfaction of patients were recorded. Results: After the second-stage operation, all the 13 patients were followed up 10-22 months, with an average of 15 months. The deformity of wrist joint disappeared after operation, and the flexion, extension, and ulnar deviation were basically normal. There was no complication such as ulnar impingement sign, nonunion or infection. Wrist function, pain, and range of motion were significantly improved after operation, except for 1 patient who had no significant improvement in rotation and pain. The ulnar internal fixator was removed at 10-18 months after the second-stage operation. The scores of pain, function, range of motion, flexion and extension range of motion, and grip strength in the Cooney wrist score before removal of internal fixator significantly improved when compared with those before operation ( P<0.05). Subjective and appearance satisfaction of patients were excellent in 9 cases, good in 3 cases, and fair in 1 case. Conclusion: Ulnar osteotomy and shortening with sequential plate internal fixation for correction of Madelung deformity, with mild postoperative pain, can effectively avoid bone nonunion, improve wrist joint function, and have significant effectiveness.

Perfusion in vivo bioreactor promotes regeneration of vascularized tissue-engineered bone.

Aim: This study improved the in vivo bioreactor (IVB) for bone regeneration by enhancing stem cell survival and promoting vascularized tissue-engineered bone. Methods: 12 New Zealand rabbits received ß-TCP scaffolds with rabbit bone mesenchymal stem cells (BMSCs) implanted. Perfusion IVB with a perfusion electronic pump was compared with the control group using micro-CT, Microfil perfusion, histological staining and RT-PCR for gene expression. Results: Perfusion IVB demonstrated good biocompatibility, increased neoplastic bone tissue, neovascularization and upregulated osteogenic and angiogenesis-related genes in rabbits (p < 0.05). Conclusion: Perfusion IVB holds promise for bone regeneration and tissue engineering in orthopedics and maxillofacial surgery.