High Conversion Rate Research Articles

Synthesis of nano-crystal PVMo2W9@[Cu6O(TZI)3(H2O)6]4⋅nH2O for catalytically biodiesel preparation

To develop efficient and reusable catalysts for biodiesel production, quaternary heteropolyacid H4PVMo2W9O40 (PVMo2W9) was effectively wrapped inside rht-MOF-1 {rht-MOF-1 = [Cu6O(TZI)3(H2O)6]4⋅nH2O}, affording a crystalline H4PVMo2W9O40@rht-MOF-1 (1) by one-pot hydrothermal method. The identification of the crystal structure of 1 was achieved through the utilization of X-ray crystallography. Nano-size crystals of 1 (n-1) were prepared with the assistance of surfactant Tween 20. Notably, crystal n-1 was of cube shape grown along {100} facets rather than octahedral shape for 1. When n-1 was applied as the catalyst for the esterification reactions, high conversion rates were achieved. E. g. about 97 % conversion for oleic acid to the corresponding monoalkyl esters and about 87 % for rapeseed oil to biodiesel. The catalyst was heterogeneous and recyclable 7 times without obvious attenuation. Further, the correlation between the catalytic activity and structure of n-1 was investigated in terms of the distribution of active sites, various pores in rht-MOF-1, and the accessibility of catalytic sites on the {100} facets.

Migration pathway and solidification mechanism of heavy metal Pb during the conversion of municipal solid waste incineration fly ash into ettringite and simultaneously purification of chloride salts solution process

The solidification/stabilization of heavy metals and valuable component recovery from municipal solid waste incineration (MSWI) fly ash are of great significance for its safe disposal. In this study, MSWI fly ash was transformed into a new solid phase mainly composed of ettringite, achieving the solidification of excessive heavy metal Pb while obtaining a mixed solution of sodium chloride and potassium chloride with extremely low impurity content, which can be recovered by evaporation-crystallization respectively. The solidification mechanism of heavy metal Pb by ettringite was investigated through a combination of DFT calculations and experiments. The results indicate that a high conversion rate of calcium ions (99.68%), separation rate of chloride (95.99%), and conversion rate of heavy metal Pb (99.42%) can be achieved by controlling the ions ratio of the MSWI fly ash reaction system to n(Ca2+):n(Al3+):n(SO42−) = 6:2:3. DFT calculations show that the reaction pathway of the formation of a vacancy-Pb entering the vacancy at the Ca-2 site of ettringite is more likely to occur. The substitution of heavy metal Pb at the Ca-2 site leads to an increase in the unit cell volume, redistribution of charges, and a decrease in the thermal stability of the ettringite. The solidified body of ettringite presents a promising potential for application in cement-based materials due to its negligible risk of heavy metals leaching and low chloride content.

1D modeling of methanation reactor with circulation (MeRCi) for assessment of reaction characteristics

For a power-to-gas (PtG) system, methanation has attracted attention to synthesize methane from carbon dioxide and hydrogen. There is a problem that heat generated by the reaction causes thermal degradation of the catalyst. Then, we have proposed a methanation reactor with circulation (MeRCi), where the temperature of the catalyst bed is controlled by recycling a part of the product gas. In this study, a one-dimensional model of the MeRCi was developed, and the methanation process was numerically simulated for assessment of reaction characteristics. The catalyst amount, the recycle ratio, and the catalyst bed length were changed. For comparison, the simulation of a straight-tube fixed-bed reactor was also simulated. Based on the gas temperature distribution of the straight-tube reactor, the simulation results show a good agreement with the experimental data, and the validity of our numerical model was confirmed. Even for the higher recycle ratio, the methane conversion rate at the reactor outlet does not change much, showing the high conversion rate within the simulation conditions. The increase of the catalyst packing density as well as the catalyst bed length enlarges the methane conversion rate. By considering the fact that the methane conversion rate is sufficiently high when the catalyst packing density is over 500 kg/m3, the reaction rate must be kept at certain level to keep the high methane conversion rate. As for the catalyst bed length, there is a minimum value at which the methane conversion rate is unexpectedly dropped where unreacted hydrogen and carbon dioxide are retained in the products.

Electrical energy by electrode placement for cardioversion of atrial fibrillation: a systematic review and meta-analysis

ObjectiveElectrode patch position may not be critical for success when cardioverting atrial fibrillation (AF), but the relevance of applied electrical energy is unclarified. Our objective was to perform a meta-analysis...

Trend in breakdown of total cost of care for medical oncology over time: Learnings from the Oncology Care Model and implications for future oncology value-based care.

69 Background: Tennessee Oncology (TO) is a large, outpatient community oncology practice with over 200 providers and 35 clinical sites of care across Tennessee and northern Georgia. As an Oncology Care Model (OCM) participant, TO received claims data from Medicare during its OCM participation from 2016-2021. TO adopted continuous quality improvement initiatives to succeed in the program. Here we highlight our adoption of biosimilars and implementation of an independent clinical pathway program. Methods: OCM claims data received from Medicare were analyzed to determine total cost of care (TCOC) per the OCM methodology. TCOC subgroup analysis was conducted by percentage of spend over time on therapeutic and supportive care drugs, emergency room utilization, and hospitalizations. Biosimilar adoption and pathway utilization rates were tracked internally. Results: 27,927 OCM episodes were attributed to TO during the study period 2016-2021. During this time frame and as a percentage of TCOC, total drug spending increased from 58% to 71%. Conversely, spending on hospital and emergency room utilization as a percentage of TCOC decreased from 11.6% to 7.9% and 1.4% to 1.0%, respectively. Within drug spending, the ratio of supportive to therapeutic drug costs decreased from 29.5% to 7.5%. Despite increased spend on therapeutic drugs towards the end of the model, pathway adherence was over 90%, and trastuzumab and bevacizumab biosimilar adoption rates were over 86% and 97%, respectively. Conclusions: Relative contributions to TCOC changed over time during OCM. The percentage of costs associated with pharmaceuticals increased, while costs associated with hospitalizations and emergency room utilization decreased. Within costs for pharmaceuticals, there was a significant increase in the percentage of costs for therapeutics versus supportive care drugs. High rates of biosimilar conversion and pathway adherence suggest increased drug spend reflects a change in oncology practice, not an effect of inappropriate utilization. These trends have implications for future developments of oncology value-based care programs.

Intention to adopt improved indigenous chicken breeds among smallholder farmers in Machakos county, Kenya. Do socio-psychological factors matter?

Consumption of poultry meat, eggs, and other animal-sourced commodities has dramatically risen by almost 86 %, with the demand of indigenous chicken products almost doubling over the past few decades. In Kenya, poultry farmers prefer indigenous chicken (IC) due to their resilience to harsh climatic conditions, high feed conversion rates, delicious end products, ability to scavenge and potential to reduce greenhouse gas emissions among other factors. Despite the high demand for poultry and its products, the gap between demand and production remains high. Poultry farmers try to keep pace with the demand by integrating the recommended improved IC breeds into their production system. Although there exists some understanding on the determinants of the farmers to adopt improved IC, still there is scanty information on how socio-psychological factors influence the intention to adoption improved IC among the farmers in Kenya. Thus, this study sought to investigate the determinants of intention to adopt improved IC while specially focusing on the role of socio-psychological factors. A total of 374 IC farmers in Machakos county were selected using a multistage sampling technique. Partial Least Square - Structural Equation Modelling (PLS-SEM) was employed to analyze the data. Results from descriptive statistics showed that approximately 90 % of IC farmers in the study area were aware of the improved indigenous chicken breeds. However, the adoption of the improved IC was below average (44.9 %). The path analysis results revealed that Subjective Norm (SN) was the main determinant of farmer's intention to adopt improved IC breeds, followed by Attitude (ATT) and Perceived Behavioral Control (PBC). The study recommends more emphasis to be given to psycho-social issues through well designed public and private interventions that will promote adoption of improved breeds among IC farmers.

Enhanced removal of emerging pollutants through visible light-activated carbon nitride materials immobilized over 3D printed structures

This study investigates the performance of carbon nitride (CN) photocatalysts immobilized on 3D printed cylindrical supports for the removal of selected emerging pollutants, namely venlafaxine (VFX), citalopram (CTP), fluoxetine (FXT), and carbamazepine (CBZ), due to their rising consumption as antidepressants and the significant concerns for public health and the environment, mainly due to the direct impact of their presence in surface waters. The CN photocatalysts were synthesized using two precursors (dicyandiamide and urea), forming four different CN materials. Among the immobilized CN photocatalysts tested, the bulk CN prepared from urea (CNB-U/PLA) revealed the highest efficiency for the removal of VFX as the target antidepressant (above 90% after 30 min), which was ascribed to the lower recombination of photogenerated charges of this photocatalyst. The reuse tests confirmed the robust and effective photocatalytic performance of the CNB-U/PLA photocatalyst over multiple cycles, while its versatility with different support configurations demonstrates its adaptability and broad potential for various photocatalytic applications. The simultaneous removal of the four antidepressants was performed at low concentrations (1.8 μM), employing the most efficient immobilized photocatalyst (CNB-U/PLA), yielding remarkably high conversion rates (above 90% for VFX, CTP, and FXT, and around 70% for CBZ, after 60 min) under visible irradiation. The results demonstrate the ability of the immobilized CN system to effectively eliminate contaminants with different chemical properties. This study emphasizes the potential of this approach for comprehensive emerging pollutants removal, highlighting its significance in water treatment and environmental remediation strategies.

Thermodynamic Insights into Sustainable Aviation Fuel Synthesis via CO/CO2 Hydrogenation

The transformation of CO/CO2 hydrogenation into high-density sustainable aviation fuel (SAF) represents a promising pathway for carbon emission reduction in the aviation industry but also serves as a method for renewable energy assimilation. However, current hydrocarbon products synthesized through CO/CO2 often focus on various catalytic paths with high selectivity and high conversion rates rather than the synthesis of SAFs with complex components. This study undertakes a thermodynamic investigation into the direct or indirect synthesis of SAFs from CO/CO2 hydrogenation. By analyzing the synthesis of seven aviation fuels defined by the American Society for Testing and Materials (ASTM) D7566 standard, our study reveals a temperature-dependent reduction in the reaction driving force for all products. Specifically, for CO, ΔG transitions from approximately −88.6 J/(mol·K) at 50 °C to 26.7 J/(mol·K) at 500 °C, with the switch from negative to positive values occurring around 390 °C. Similarly, for CO2, ΔG values change from approximately −66.7 J/(mol·K) at 50 °C to 37.3 J/(mol·K) at 500 °C, with the transition point around 330 °C. The thermodynamic favorability for various hydrocarbon products synthesized is also examined, highlighting a transition at temperatures of around 250 °C, beyond which the thermodynamic drive for the synthesis of aromatic compounds increasingly surpasses that of cycloparaffin synthesis. Our findings also underscore that the products with a higher aromatic content yield a lower H2/CO2 ratio, thus reducing hydrogen consumption. The influence of cycloparaffin and aromatic proportions in the typical SAF products on the ΔG is also explored, revealing that an increase in cycloparaffin content in SAFs slightly elevates the ΔG, whereas an increase in aromatic content significantly reduces ΔG, thereby markedly enhancing the thermodynamic drive of the CO/CO2 hydrogenation reaction. These findings underscore the thermodynamic preference for synthesizing SAF with a higher proportion of aromatic compounds, shedding light on potential pathways for optimizing fuel synthesis to improve efficiency. Finally, the thermodynamic challenges and potential solutions involved in synthesizing SAFs via specific intermediate compounds are discussed, presenting opportunities for more strategic process schemes in industrial scenarios.

Does previous gastrectomy history affect the surgical outcomes of laparoscopic cholecystectomy?

PurposeThis current study aimed to explore whether gastrectomy history influenced surgical outcomes while undergoing laparoscopic cholecystectomy (LC).MethodsThe PubMed, Embase, and Cochrane Library databases were searched for eligible studies from inception to April 29, 2023. The Newcastle–Ottawa Scale (NOS) was adopted to assess the quality of included studies. The mean differences (MDs) and 95% confidence intervals (CIs) were calculated for continuous variables, and the odds ratios (ORs) and 95% CIs were calculated for dichotomous variables. RevMan 5.4 was used for data analysis.ResultsSeven studies enrolling 8193 patients were eligible for the final pooling up analysis (380 patients in the previous gastrectomy group and 7813 patients in the non-gastrectomy group). The patients in the gastrectomy group were older (MD = 11.11, 95%CI = 7.80–14.41, P < 0.01) and had a higher portion of males (OR = 3.74, 95%CI = 2.92–4.79, P < 0.01) than patients in the non-gastrectomy group patients. Moreover, the gastrectomy group had longer LC operation time (MD = 34.17, 95%CI = 25.20–43.14, P < 0.01), a higher conversion rate (OR = 6.74, 95%CI = 2.17–20.26, P = 0.01), more intraoperative blood loss (OR = 1.96, 95%CI = 0.59–3.32, P < 0.01) and longer postoperative hospital stays (MD = 1.07, 95%CI = 0.38–1.76, P < 0.01) than the non-gastrectomy group.ConclusionPatients with a previous gastrectomy history had longer operation time, a higher conversion rate, more intraoperative blood loss, and longer postoperative hospital stays than patients without while undergoing LC. Surgeons should pay more attention to these patients and make prudent decisions to avoid worse surgical outcomes as much as possible.

Analysis of unsaturated fatty acids by supercritical fluid chromatography tandem mass spectrometry coupled with online Paternò-Büchi reaction

Carbon double bond (CC) positions in unsaturated fatty acids (UFAs) can be identified based on Paternò-Büchi (PB) reaction coupled with mass spectrometry (MS). However, achieving a high conversion rate and confusing mass spectrum are still challenging. In this study, an online PB reaction coupled with supercritical fluid chromatography-mass spectrometry (SFC-MS), using a homemade flow microreactor, was established to analyze CC bonds in UFAs, and benzaldehyde (BA) was proposed as the optimized reagent. Benefiting from this setup, both prototype and product ions of FAs can be rapidly captured at the same retention time, significantly enhancing the accuracy of lipid identification, especially when dealing with complex compounds. Furthermore, a high CC bond conversion rate was achieved, ranging from 53 to 67 %. Additionally, this strategy demonstrated excellent relative quantification abilities, which were based on the ratios of either the sum of diagnostic ions or the individual diagnostic ions. This novel approach was proposed and applied for the specific recognition of free FA in human plasma, which successfully provides quantitative information about UFA isomers. This strategy is believed to hold promise for the analysis of unsaturated lipid isomers in complex biological samples.

In situ electrolyte replenishment with atmospheric pressure-chemical/electrochemical vapour deposition for molten carbonate fuel cells

Molten carbonate fuel cells (MCFCs) offer several advantages in energy applications, but their lifetime is limited especially by electrolyte depletion. In this study, a novel in situ method for replenishing the electrolyte in MCFCs by injecting gaseous electrolyte precursors (EP) that form liquid electrolyte through reactions with CO2/O2 gases or CO32- ions is introduced. The selection of EP species (LiI, NaI, and KOH) are guided by thermodynamic considerations including high vapour pressures and conversion rates to Li/K or Li/Na carbonates. The proposed approach addresses two electrolytic depletion stages: consumption of the electrolyte in the electrode (Stage 1) and in the matrix pores (Stage 2). Atmospheric-pressure electrochemical vapour deposition (AP-EVD) and atmospheric-pressure chemical vapour deposition (AP-CVD) are demonstrated to replenish electrolyte in the electrode and matrix pores, respectively. The applied techniques sustained a cell with a low (Li/Na)2CO3 electrolyte level for long-term operation (>1,000 h) while maintaining stable performance (>0.8 V at 150 mA cm−2). The method also returned an inactive cell to its normal operating conditions (OCV: 1.054 V, RΩ: 0.61 Ω cm2, (Li/K)2CO3 electrolyte). These results promise enhanced durability of MCFCs and render them much more viable for use in energy applications.

Entropy Confinement Promotes Hydrogenolysis Activity for Polyethylene Upcycling.

Chemical upcycling that catalyzes waste plastics back to high-purity chemicals holds great promise in end-of-life plastics valorization. One of the main challenges in this process is the thermodynamic limitations imposed by the high intrinsic entropy of polymer chains, which makes their adsorption on catalysts unfavorable and the transition state unstable. Here, we overcome this challenge by inducing the catalytic reaction inside mesoporous channels, which possess a strong confined ability to polymer chains, allowing for stabilizing transition state. This approach involves the synthesis of p-Ru/SBA catalysts, in which Ru nanoparticles are uniformly distributed within the channels of an SBA-15 support, using a precise-impregnation method. The unique design of the p-Ru/SBA catalyst has demonstrated significant improvements in catalytic performance for the conversion of polyethylene into high-valued liquid fuels, particularly diesel. The catalyst achieved a high solid conversion rate of 1106 g·gRu-1·h-1 at 230 °C. Comparatively, this catalytic activity is 4.9 times higher than that of a control catalyst, Ru/SiO2, and 14.0 times higher than that of a commercial catalyst, Ru/C, at 240 °C. This remarkable catalytic activity opens up immense opportunities for the chemical upcycling of waste plastics.

Entropy Confinement Promotes Hydrogenolysis Activity for Polyethylene Upcycling

AbstractChemical upcycling that catalyzes waste plastics back to high‐purity chemicals holds great promise in end‐of‐life plastics valorization. One of the main challenges in this process is the thermodynamic limitations imposed by the high intrinsic entropy of polymer chains, which makes their adsorption on catalysts unfavorable and the transition state unstable. Here, we overcome this challenge by inducing the catalytic reaction inside mesoporous channels, which possess a strong confined ability to polymer chains, allowing for stabilization of the transition state. This approach involves the synthesis of p‐Ru/SBA catalysts, in which Ru nanoparticles are uniformly distributed within the channels of an SBA‐15 support, using a precise impregnation method. The unique design of the p‐Ru/SBA catalyst has demonstrated significant improvements in catalytic performance for the conversion of polyethylene into high‐value liquid fuels, particularly diesel. The catalyst achieved a high solid conversion rate of 1106 g ⋅ gRu−1 ⋅ h−1 at 230 °C. Comparatively, this catalytic activity is 4.9 times higher than that of a control catalyst, Ru/SiO2, and 14.0 times higher than that of a commercial catalyst, Ru/C, at 240 °C. This remarkable catalytic activity opens up immense opportunities for the chemical upcycling of waste plastics.

Isolated Arthroscopic Debridement of Acetabular Labral Tears: High Rates of Failure and Conversion to Total Hip Arthroplasty at 13-Year Minimum Follow-up

Background: Historically, symptomatic hip labral lesions were treated with arthroscopic debridement. Hip labral repair has become the standard treatment for labral pathology; however, to date, there are limited long-term studies regarding the outcomes of isolated labral debridement. Purpose: To (1) evaluate the long-term patient-reported outcomes of isolated labral debridement, (2) report reoperation and arthroplasty rates, and (3) identify risk factors contributing to reoperation or poor clinical outcomes. Study Design: Case series; Level of evidence, 4 Methods: A retrospective review of a prospectively generated cohort of 59 hips in 57 patients from 1996 to 2010 who underwent hip arthroscopy with labral debridement was performed. Only patients with Tönnis grade <3 were included. Additionally, given the time period analyzed, resection of cam morphology was not performed, and the interportal capsulotomy was not repaired. The pre- and postoperative modified Harris Hip Score; Hip Outcome Score (HOS)-Activities of Daily Living and -Sports scores; and reoperation, conversion to total hip arthroplasty, and risk factors were analyzed. Results: In total, 48 hips in 47 patients (14 men, 33 women; mean age, 48.0 ± 12.9 years) met inclusion criteria and were followed for a mean of 17 ± 3 years (range, 13-27 years). The mean preoperative Tönnis grade was 1.3 ± 0.6 (range, 0-2), the mean chondral acetabular International Cartilage Regeneration & Joint Preservation Society (ICRS) grade was 1.7 ± 1.6 (range, 0-4), the mean chondral femoral ICRS grade was 0.9 ± 1.4, and the mean acetabular labral articular cartilage grade was 2.5 ± 1.2 (range, 0-4). At the final follow-up, mean the modified Harris Hip Score, HOS-Activities of Daily Living score, and HOS-Sports score were 82.2 ± 16.6, 81.9 ± 20.5, and 82.2 ± 20.5, respectively. Nineteen hips underwent subsequent reoperation at a mean of 5.5 ± 6.2 years (range, 0.5-21.2 years) postoperatively, including 16 hips (33% overall) being converted to total hip arthroplasty. Higher acetabular ICRS chondral grades at the time of surgery were observed in patients who went on to subsequent surgery compared with those who did not (2.3 ± 1.6 vs 1.1 ± 1.5; P = .02). In reoperation-free hips, Tönnis grade demonstrated a trend of increasing over time (1.4 preoperatively vs 1.7 at radiographic follow-up; P = .08). At the final follow-up, 19 hips (40%) had undergone reoperation, and 5 additional hips (10%) were rated as “abnormal” or “severely abnormal” in function, resulting in an overall clinical failure rate of 50%. Conclusion: Isolated labral debridement was found to result in high rates of failure and reoperation, with a third of patients being converted to arthroplasty and half of patients meeting criteria for reoperation or clinical failure. Of note, for patients remaining reoperation-free, satisfactory outcome scores were observed.

A Review of Top-Submerged Lance (TSL) Processing—Part I: Plant and Reactor Engineering

Part I of this series of papers focuses on plant and reactor engineering aspects of the TSL reactor technology. A general flowsheet is presented, while emphasis is given to the definition of different reactor zones in terms of fluid dynamics and occurring reactions. Then, the technical advantages of TSL processing, such as feed flexibility and high conversion rates (due to induced turbulence), low dust generation, and low fugitive emissions, are explained. In addition, the reactor is analyzed part by part, also taking into account patent literature, focusing on furnace design, settling furnaces for molten phase disengagement, feeding systems regarding input material streams such as concentrates and fuels, vessel cooling arrangements, off-gas system, and aspects associated with the refractory lining. Furthermore, specific focus is given to the centerpiece of the TSL reactor, i.e., the reactor lance. Associated developments have focused on establishing a slag coating to hinder lance wear, i.e., the development of cooling mechanisms (e.g., use of fluid-cooled lance and shroud arrangements), the increment of O2 enrichment within the incoming air stream, and influencing of fluid dynamics (e.g., O2 conversion at the lance tip, bubble formation, and bath splashing). Finally, comprehensive tables concerning process developments and commissioned TSL plants are provided thus concluding Part I of the review.

PdCu nanoalloy decorated photocatalysts for efficient and selective oxidative coupling of methane in flow reactors

Methane activation by photocatalysis is one of the promising sustainable technologies for chemical synthesis. However, the current efficiency and stability of the process are moderate. Herein, a PdCu nanoalloy (~2.3 nm) was decorated on TiO2, which works for the efficient, stable, and selective photocatalytic oxidative coupling of methane at room temperature. A high methane conversion rate of 2480 μmol g−1 h−1 to C2 with an apparent quantum efficiency of ~8.4% has been achieved. More importantly, the photocatalyst exhibits the turnover frequency and turnover number of 116 h−1 and 12,642 with respect to PdCu, representing a record among all the photocatalytic processes (λ > 300 nm) operated at room temperature, together with a long stability of over 112 hours. The nanoalloy works as a hole acceptor, in which Pd softens and weakens C-H bond in methane and Cu decreases the adsorption energy of C2 products, leading to the high efficiency and long-time stability.

Clinical Outcomes of a Percutaneous Cholecystostomy for Acute Cholecystitis – A Tertiary Center Experience

Background: In surgically high-risk patients with acute cholecystitis (AC), percutaneous cholecystostomy (PC) is an effective procedure. This study aimed to study the clinical outcomes of PC and to assess predictors for recurrence following PC placement. Methodology: A retrospective data review of all patients who underwent a PC for AC between 2010 and 2020 was performed. Results: Seventy-one patients underwent a PC with a mean age of 61.35 years (standard deviation: 14.11); 59 (83.1%) were male; 32 (45.1%) were the American Society of Anesthesiologists III and IV. Forty (56.3%) patients had multiple comorbid illnesses; 70 (98.6%) patients had Grade 2, 3 cholecystitis. All patients had ultrasound-guided drainage; 63 (88.7%) had transhepatic route. The mean duration till PC removal was 51.58 (1–313) days. Eleven (15.5%) patients developed recurrence after PC placement over a median of 40 (29–102) days; 6 (54.5%) were managed nonoperatively, 3 (27%) underwent laparoscopic cholecystectomy, and 2 (18%) developed cholangitis. After index admission with AC managed by PC, thirty-nine (54.9%) patients underwent cholecystectomy; 4(5.6%) at the index admission, 35 (49.3%) elective interval cholecystectomies. The rate of conversion to open at interval cholecystectomy among patients with no recurrence in the interval period was 31.88% (7/22), and 50% for patients with recurrent AC. Five (7.04%) patients had mortality at the index admission, and the overall 1-year mortality was 8.45% (6/71). Conclusion: A high clinical success rate and less procedure-related morbidity make PC a favorable procedure in surgically high-risk patients. Patients with a recurrent episode of AC were found to have higher rates of conversion at interval cholecystectomy. No specific predictor for recurrence was identified.

Engineering a localized electrostatic environment to enhance hydroxyl activating for electrocatalytic biomass conversion

The 5-hydroxymethylfurfural electrocatalytic oxidation reaction (HMFOR) is a sustainable and efficient route for converting biomass platform molecules into high-value chemicals. The HMFOR process involves the simultaneous oxidation of hydroxyl and aldehyde groups. Optimizing the reaction pathways by modulating the adsorption behavior of 5-Hydroxymethylfurfural molecules toward a higher conversion rate is vital for achieving an efficient HMFOR. In this study, the HMFOR electrocatalytic performance of NiO was enhanced by regulating the surface microenvironment through the decoration of NiO nanosheets with polypyrrole (PPy). Operando Fourier transform infrared spectroscopy, density functional theory calculation, and electrochemical behavior characterizations demonstrated that electropositive PPy can optimize the adsorption behavior of electronegative hydroxyl groups and modulate the reaction pathway toward the formation of 2,5-diformylfuran intermediates. By modulating the local microenvironment, the designed NiO-PPy catalyst showed excellent HMFOR performance with a threefold increase in current density. This study emphasizes the significance of the surface microenvironment in modulating reaction pathways to achieve selective biomass electrocatalytic conversion.

Ultrawideband Tunable Polarization Converter Based on Metamaterials

In order to overcome the shortcomings of the traditional polarization conversion device, a symmetric “E” type metamaterial resonance cell structure is proposed in the paper for the design of polarization conversion devices. Two kinds of polarization converter models are designed in this paper, and their polarization coefficient, phase and polarization conversion ratio (PCR) are simulated and analyzed. The polarization coefficients at different incident angles and different phase transitions of VO2 are simulated and analyzed. The study indicates that the polarization conversion efficiency of the polarization converter reaches 90% in the 0–2.0 THz frequency band, and the performance can be maintained within the incident angle of 45 degrees, covering the whole X band, realizing the broadband line polarization conversion with extremely high polarization conversion rate. Moreover, the polarization performance is tunable with the phase transition of VO2, and the research results provide new ideas for the realization of ultrawideband tunable polarization conversion devices and the application of metamaterials.

RETRACTED ARTICLE: Efficacy and safety of arthroscopy in femoroacetabular impingement syndrome: a systematic review and meta-analysis of randomized clinical trials

This study aimed to compare the efficacy and safety of arthroscopy with physiotherapy or joint lavage in patients with femoroacetabular impingement (FAI). A meta-analysis using PubMed, Embase, Scopus, and the Cochrane Collaboration Library databases was performed in September 2022. We included studies focusing on patients with FAI who underwent arthroscopic surgery versus those who underwent physiotherapy or arthroscopic lavage. The outcomes were functional scores (iHOT-33 and HOS ADL) and adverse events. Randomized clinical trials were included in the study. The risk of bias in each study was assessed according to Cochrane guidelines for clinical trials. The data were combined using Review Manager version 5.4. (PROSPERO CRD42022375273). Six RCTs were included, from a pool of 839 patients (407 females). The iHOT-33 and HOS ADL scales showed significant differences at 12 months in favor of the arthroscopy group (MD, 10.65; 95% CI 6.54–4.76) and (MD, 8.09; 95% CI 3.11–13.07). MCID was not achieved through arthroscopy in functional variables. The rates of osteoarthritis (OR, 6.18; 95% CI 1.06–36.00) and numbness (OR, 73.73; 95% CI 10.00–43.92) were significantly higher in the arthroscopy group. Arthroscopic surgery showed statistical superiority over the control group without exceeding the MCID in most studies; however, the results might have been influenced by secondary variables. Finally, arthroscopic surgery results in a high rate of conversion to osteoarthritis.