Low Conversion Rate Research Articles

Nitrate-promoted gas–solid reactions of H2 and CaCO3 for mid-temperature integrated CO2 capture and methanation

Integrated CO2 capture and methanation (ICCM) technology has attracted increasing attention for Carbon Neutrality. However, in the mid-temperature ICCM studies dominated by MgO, which involves the gas–gas catalytic pathway, the problems of high CO2 escape and low CH4 yield are common. Replacing MgO with CaO reduced CO2 escape because the reaction proceeded via the gas–solid pathway. However, the lower CaCO3 conversion rate limits its further applications. Here, we present an ICCM process with efficient CaCO3 conversion using alkali metal nitrates (KNO3, LiNO3, and (Li-K)NO3) to promote Ru/CeO2-CaO. The results showed that the doping of nitrates led to a decrease in the specific surface area of CaO, thus losing part of the CO2 capture performance. On the other hand, forming the molten liquid layer facilitated the gas–solid reaction between CaCO3 and H2, which improved the CaCO3 conversion. Compared with the Ru/CeO2-Neat CaO without nitrate promotion, the CaCO3 conversion of Ru/CeO2-KNO3/CaO was increased by 42% and CH4 yield by 52% after five ICCM cycles. Furthermore, kinetic analysis and in situ DRIFTS experiments demonstrated that molten KNO3 facilitated mass transfer in the diffusion-controlled stage of direct CaCO3 hydrogenation.

Optimization of immobilized urease enzyme on porous polymer for enhancing the stability, reusability and enzymatic kinetics using response surface methodology

The study examines the immobilization of the urease enzyme on a range of High Internal Phase Emulsion (polyHIPE) materials, assessing characteristics, efficiency, and performance. It also investigates the impact of polyHIPE type, quantity, incubation time, and various parameters on the process and enzyme activity. Surface morphology and functional groups of polyHIPE materials were determined through scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FT-IR) analyses, revealing significant alterations after modification with polyglutaraldehyde (PGA). The maximum immobilization efficiency of 95% was achieved by adding PGA to polyHIPE materials with an incubation period of 15 h. The optimized conditions for immobilized enzyme using a Box-Behnken design (BBD) of response surface methodology (RSM) were as follows: temperature (40.8 °C), pH (7.1) and NaCl concentration (0.007 g/L). Furthermore, the immobilized enzyme demonstrated remarkable reusability, retaining 75% of its initial activity after six cycles, and sustained shelf-life stability, retaining over 40% activity after 10 days at room temperature. Kinetic analyses revealed that immobilized urease exhibited higher affinity for the substrate, but lower rate of substrate conversion compared to the free enzyme. These findings offer valuable insights into optimizing urease immobilization processes and enhancing urease stability and activity, with potential applications in various fields, including biotechnology and biocatalysis.

Performance Evaluation of School Enterprise Collaborative Innovation and Practice of Innovation and Entrepreneurship Education Based on the Improved AHP Fuzzy Comprehensive Evaluation Method

Under the influence of the COVID-19, great changes have taken place in China’s economic structure and market subjects and college students are facing difficulties in employment. By carrying out collaborative innovation between schools and enterprises, cultivating high-quality talents to meet social needs has become an important way to solve difficulties. Based on the input-process-output principle, a performance evaluation index system for collaborative innovation is constructed, which includes 3 primary indicators and 22 secondary indicators. The weights of each indicator are determined using improved AHP. A mathematical model for evaluating the performance of school enterprise collaborative innovation is established using the fuzzy comprehensive evaluation method. The evaluation value of the innovation and entrepreneurship education case project is 0.82, indicating that the overall operation is in good condition. The cooperation between schools and enterprises has created a favorable atmosphere and accumulated rich experience for carrying out innovation and entrepreneurship education. Good results have been achieved in talent cultivation and scientific and technological output, but there are also problems such as low conversion rates of scientific and technological achievements. Based on the evaluation results, the article proposes suggestions to improve the performance of collaborative innovation between schools and enterprises. The research results provide theoretical reference for the performance evaluation of school enterprise collaborative innovation and the practice of innovation and entrepreneurship education.

A flexible sanded cotton fabric coated with Au@polypyrrole for seawater desalination

Nowadays, freshwater has increasingly become a scarce resource. Seawater distillation is limited due to the high costs and low conversion rates. Herein, a functional cotton fabric with significant photothermal properties was prepared through a simple sanding treatment, followed by a polypyrrole (PPy) and Au nanoparticles coating. The functional materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and thermogravimetric analysis. The solar water evaporation measurements showed that the sanded cotton fabrics coated Au@PPy exhibited excellent photothermal conversion with an energy efficiency being 93.38 % for solar-steam generation under 1.0 sun irradiation, corresponding to a water evaporation rate of 1.33 kg·m−2·h−1. Moreover, the coated fabric also exhibited excellent tolerance to acidic and alkaline conditions.

Hybrid-DFT study of halide perovskites, an energy-efficient material under compressive pressure for piezoelectric applications

Recent studies have reported that lead-halide perovskites are the most efficient energy-harvesting materials. Regardless of their high-output energy and structural stability, lead-based products have risk factors due to their toxicity. Therefore, lead-free perovskites that offer green energy are the expected alternatives. We have taken CsGeX3 (X = Cl, Br, and I) as lead-free halide perovskites despite knowing the low power conversion rate. Herein, we have tried to study the mechanisms of enhancement of energy-harvesting capabilities involving an interplay between structure and electronic properties. A density functional theory simulation of these materials shows a decrease in the band gaps, lattice parameters, and volumes with increasing applied pressure. We report the high piezoelectric responses and high electro-mechanical conversion rates, which are intriguing for generating electricity through mechanical stress.

Robotic, transanal, and laparoscopic total mesorectal excision for locally advanced mid/low rectal cancer: European multicentre, propensity score-matched study.

Total mesorectal excision (TME) is the standard surgery for low/mid locally advanced rectal cancer. The aim of this study was to compare three minimally invasive surgical approaches for TME with primary anastomosis (laparoscopic TME, robotic TME, and transanal TME). Records of patients undergoing laparoscopic TME, robotic TME, or transanal TME between 2013 and 2022 according to standardized techniques in expert centres contributing to the European MRI and Rectal Cancer Surgery III (EuMaRCS-III) database were analysed. Propensity score matching was applied to compare the three groups with respect to the complication rate (primary outcome), conversion rate, postoperative recovery, and survival. A total of 468 patients (mean(s.d.) age of 64.1(11) years) were included; 190 (40.6%) patients underwent laparoscopic TME, 141 (30.1%) patients underwent robotic TME, and 137 (29.3%) patients underwent transanal TME. Comparative analyses after propensity score matching demonstrated a higher rate of postoperative complications for laparoscopic TME compared with both robotic TME (OR 1.80, 95% c.i. 1.11-2.91) and transanal TME (OR 2.87, 95% c.i. 1.72-4.80). Robotic TME was associated with a lower rate of grade A anastomotic leakage (2%) compared with both laparoscopic TME (8.8%) and transanal TME (8.1%) (P = 0.031). Robotic TME (1.4%) and transanal TME (0.7%) were both associated with a lower conversion rate to open surgery compared with laparoscopic TME (8.8%) (P < 0.001). Time to flatus and duration of hospital stay were shorter for patients treated with transanal TME (P = 0.003 and 0.001 respectively). There were no differences in operating time, intraoperative complications, blood loss, mortality, readmission, R0 resection, or survival. In this multicentre, retrospective, propensity score-matched, cohort study of patients with locally advanced rectal cancer, newer minimally invasive approaches (robotic TME and transanal TME) demonstrated improved outcomes compared with laparoscopic TME.

Highly dispersed active sites and strong metal-support interaction for boosting CO2 hydrogenation to methanol

As global energy demand continues to increase and global climate change issues caused by greenhouse gas emissions gradually heat up, the effective conversion of carbon dioxide into high value-added methanol has become a key challenge in the energy and environmental fields. However, due to the chemical inertness of CO2 molecules, it is difficult to activate CO2 at low temperatures, resulting in extremely low conversion rates. Although increasing the reaction temperature is beneficial for the conversion of CO2, there is also competition in the reverse water gas reaction, resulting in lower methanol selectivity. Therefore, developing efficient catalysts is the key to improving CO2 conversion rate and methanol selectivity. In this work, we used zirconium-based UIO-66 metal-organic framework as a precursor, replaced the original terephthalic acid ligand with thermally unstable aminoterephthalic acid, and supported Cu on the MOF precursor by equal volume impregnation method. After heat treatment, the Cu/ZrO2-DM catalyst was prepared. The catalyst was compared with Cu/ZrO2 catalyst prepared by co-precipitation method, hydrothermal method and unmodified Cu/ZrO2-D catalyst. The Cu/ZrO2-DM catalyst exhibited the highest CO2 conversion and methanol selectivity in the hydrogenation reaction, reaching 13.95% and 90.78%, respectively. The main reason is attributed to the large specific surface area of the copper-based catalyst derived from MOF materials, the good dispersion of the active center and the strong interaction between Cu and the precursor. This work may provide a new perspective for the design and synthesis of related catalytic materials for efficient CO2 hydrogenation to methanol.

Conversion to Radical Nephrectomy From Robotic Partial Nephrectomy Is Most Commonly Due to Anatomic and Oncologic Complexity.

Partial nephrectomy is standard-of-care treatment for small renal masses. As utilization of partial nephrectomy increases and includes larger and complex tumors, the risk of conversion to radical nephrectomy likely increases. We evaluated incidence and reason for conversion to radical nephrectomy in patients scheduled for partial nephrectomy by surgeons participating in MUSIC (the Michigan Urologic Surgery Improvement Collaborative). All patients in whom robotic partial nephrectomy was planned were stratified by completed procedure (robotic partial nephrectomy vs radical nephrectomy). Preoperative and intraoperative records were reviewed for preoperative assessment of difficulty and reason for conversion. Patient, tumor, pathologic, and practice variables were compared between cohorts. Of 650 patients scheduled for robotic partial nephrectomy, conversion to radical nephrectomy occurred in 27 (4.2%) patients. No conversions to open were reported. Preoperative documentation indicated a plan for possible conversion in 18 (67%) patients including partial with possible radical (n = 8), partial vs radical (n = 6), or likely radical nephrectomy (n = 4). Intraoperative documentation indicated that only 5 (19%) conversions were secondary to bleeding, with the remaining conversions due to tumor complexity and/or oncologic concerns. Patients undergoing conversion had larger (4.7 vs 2.8 cm, P < .001) and higher-complexity tumors (64% vs 6%, P < .001) with R.E.N.A.L. (for radius, exophytic/endophytic, nearness of tumor to collecting system, anterior/posterior, location relative to polar line) nephrometry score ≥ 10. The converted cases had a higher rate of ≥ pT3 (27% vs 8.4%, P = .008). There was a low rate of conversion from robotic partial to radical nephrectomy in the MUSIC-KIDNEY (Kidney mass: Identifying and Defining Necessary Evaluation and therapY) collaborative, and an even lower risk of conversion due to uncontrolled bleeding. Targeted review of each conversion identified appropriate decision-making based on oncologic risk in most cases.

Surgical outcomes of transvaginal natural orifice transluminal endoscopy in treating ovarian cysts and risk factors for surgical conversions

ObjectiveThis study aimed to assess the surgical outcomes and identify the conversion risk factors of Transvaginal Natural Orifice Transluminal Endoscopic Surgery (vNOTES) in treating ovarian cyst. MethodsThis was a retrospective study of 505 patients who underwent vNO TES for treating ovarian cyst from March 2019 to February 2022 wherein the patients were classified into “converted” or “nonconverted” groups. T-tests, χ2 tests, and logistic regression were used for statistical analyses. ResultsThere were 16 (3.17 %) surgical conversions and 12 (2.38 %) other surgical complications in our study cohort. Teratomas accounted for 56.8 % of complications in nonconverted cases and 18.8 % in converted cases. Adenocystomas were found in 12.3 % of nonconverted cases and 18.8 % of converted cases. Other types included paraovarian cysts (3.3 % and 0 %), fibroma, granulosa cell tumor, Brenner tumor (1.2 % and 0 %), corpus luteum cysts, follicular cysts (7.6 % and 6.3 %), old abscess (0.2 % and 0 %), and simple cysts (17.6 % and 12.5 %) in the nonconverted and converted groups, respectively. The converted group included more cases of endometriotic cysts (43.8 % vs 12.3 %, p = 0.023), bilateral cysts (37.5 % vs 8.2 %, p < 0.001), severe pelvic adhesion (68.8 % vs 3.3 %, p < 0.001), deep endometriosis (12.5 % vs 0.4 %, p < 0.001), and at least two cysts (37.5 % vs 8.81 %; p < 0.001). Severe pelvic adhesion (adjusted odds ratio [OR], 86.96; range, 18.33–431.77; p < 0.001), bilateral cysts (adjusted OR, 4.75; range, 1.05–21.57, p = 0.043) and endometriotic cysts (adjusted OR, 7.69; range, 3.11–17.08; p < 0.001) were also predictors of surgical conversion. ConclusionvNOTES demonstrates low complication and conversion rates in treating ovarian cyst compared with TU-LESS. Surgical conversion is associated with severe pelvic adhesions, bilateral cysts, and endometriotic cysts.

A Study of ZSM-5 Molecular Sieve Shaping for an Innovative Cyclohexene Hydration Process

The development of the zeolite molecular sieves (ZSM-5) molding technique is essential for the cyclohexene hydration reaction distillation process in both industrial and research settings. The reactive distillation process can solve many of the drawbacks associated with the existing technique of manufacturing cyclohexanol via cyclohexene hydration, such as high catalyst digestibility, low conversion rate, and operational challenges. This study developed a series of molded ZSM-5 catalysts with various binder types and contents were constructed. The suggested pseudo-boehmite and hydroxypropyl methylcellulose were chosen as binders for extrusion molding of ZSM-5. The effects of binders on the strength reliability were investigated by strength tests and statistical analysis of the Weibull function. The effects of binders on the physical structure, acidity, and catalytic performance of ZSM-5 were investigated by X-ray diffraction, scanning electron microscopy, physical adsorption of N2, and desorption of NH3. The findings demonstrate that the addition of binder has no effect on ZSM-5's crystal structure. The experiment's results showed that the molded catalyst could be used for the hydration process with over 95% selectivity and a yield of 10.45% cyclohexanol. Copyright © 2024 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Conversion rate to open surgery during transanal total mesorectal excision (TaTME) for rectal cancer: a single-center experience

Minimally invasive techniques for rectal cancer have demonstrated considerable advantages in terms of faster recovery and less post-operative complications. However, due to the complex anatomy and a limited surgical field, conversion to open surgery is still sometimes required, with a negative impact on the short-and long-term outcomes. The purpose of this study was to analyse the conversion rate to open abdominal surgery during laparoscopic transanal total mesorectal excision (TaTME) procedures performed at a high-volume Italian referral center. All consecutive TaTME performed for mid-to-low rectal cancer between 2015 and 2023 were reviewed, independently if treated with a primary anastomosis (with/without a diverting ostomy) or an end stoma. All procedures were performed using a standardized approach by the same surgical team. Patients with benign diagnosis that underwent different-from rectal resection procedures and cases pre-operatively scheduled for open surgery were excluded. The primary outcome of interest was the rate of conversion, defined as an un-planned intraoperative switch to open surgery using a midline laparotomy. Secondary aims included the comparison of patients who had a longer vs shorter operative time. Out of 220 patients, 210 were selected. In 187 cases, a primary anastomosis was performed, while 23 patients received a terminal colostomy (1 in the converted group; 22 in the full MIS- TaTME group, 10.6%). A surgical approach modification occurred in two cases, with a conversion rate of 0.95%. Median operative time was 281 min. Reasons for conversions included intra-operative difficulties impairing the mini-invasive procedure without intra-operative complications in one case, and difficulties in the laparoscopic control of an intraoperative bleeding due to a splenic lesion in another patient. Male sex and a higher BMI were found to be statistically significantly associated to longer operative time (respectively: p = 0.001 and p = 0.0025). In a high-volume center, a standardized TaTME is associated to a low conversion rate to open abdominal surgery.

Different effects of mesophilic and thermophilic anaerobic digestion on subsequent pyrolysis: Characteristics, kinetics and thermodynamic analysis

Anaerobic digestion (AD) combined with pyrolysis has been used as an innovative sludge-to-energy process that enhances energy recovery. This study investigated the different impacts of mesophilic and thermophilic AD on subsequent pyrolysis. The pyrolysis characteristics, kinetics, and thermodynamics of raw sludge (RS) and digested sludge (DS) after both mesophilic and thermophilic AD were investigated using thermogravimetric analysis (TGA) and three kinetic models (Starink, Flynn–Wall–Ozawa, Kissinger–Akahira–Sunose). TGA results indicated that thermophilic AD reduced the weight loss from 71.2-75.6 % for RS to 55.0–59.1 % for DS, more considerably than mesophilic AD (reducing from 70.6-75.2 % to 61.3–69.5 %), indicating higher organic matter removal. Kinetic analysis showed that the activation energy (E) of RS and DS pyrolysis ranged from 128.9 to 399.9 kJ/mol and 117.3 to 470.4 kJ/mol, respectively. Mesophilic AD generally increased the E, while thermophilic AD did not markedly alter E at low conversion rates (0.2–0.5) but increased it at high conversion rates (0.6–0.8), changing from 203.7–399.9 kJ/mol for RS to 248.9–470.4 kJ/mol for DS. Thermodynamic analysis showed that mesophilic AD generally enhanced pyrolysis favorability and reactivity but impeded activated complex formation. Thermophilic AD enhanced favorability and favored complex formation at low conversion rates but hindered it at high conversion rates. Reactivity varied with thermophilic AD extent, with excessive AD reducing reactivity. Pyrolysis–gas chromatography/mass spectrometry analysis confirmed that AD, on the one hand, decomposed biodegradable organics into low-molecular-weight organics, retained them in the DS, and facilitated subsequent pyrolysis. On the other hand, AD could accumulate large bio-refractory molecules, rendering DS less prone to pyrolytic decomposition. This effect of thermophilic AD was more significant than that of mesophilic AD. Given more favorable change was observed in kinetics and thermodynamics at lower conversion rates, low-temperature pyrolysis to produce biochar might be a promising strategy for DS treatment. The insights gained in this study may guide the optimization of AD conditions to maximize the efficiency of subsequent pyrolysis, providing more insight into the thermochemical conversion of DS and pyrolysis design.

Transumbilical laparoscopy for pneumoperitoneum establishment: a comprehensive multicentre evaluation affirming safety, feasibility, and a range of clinical benefits.

Transumbilical laparoscopy (TUL) has emerged as a promising technique for establishing pneumoperitoneum in laparoscopic cholecystectomy, offering potential safety, feasibility, and clinical benefits. This retrospective multicentre study aims to evaluate the efficacy and outcomes of TUL in the management of gallbladder diseases. A retrospective analysis was conducted on a cohort of 2,543 patients who underwent TUL between 2011 and 2021 across various medical institutions in Italy. Data collection included demographic, clinical, intraoperative, and postoperative parameters. Standardized protocols were followed for preoperative and postoperative management. The TUL technique involved precise anatomical incision and trocar placement. The study demonstrated favorable outcomes associated with TUL, including a low conversion rate to open surgery (0.55%), minimal intraoperative complications (0.16%), and short hospital stays (average 2.4 days). The incidence of incisional hernias was notably low (0.4%). Comparison with existing literature revealed consistent findings and provided unique insights into the advantages of TUL. Despite limitations, such as the absence of a control group and the retrospective nature of the study, the findings contribute valuable insights to the literature. They inform surgical decision-making and advance patient care in laparoscopic cholecystectomy for gallbladder diseases. Transumbilical laparoscopy shows promise as a safe and feasible technique for establishing pneumoperitoneum in laparoscopic cholecystectomy. The study's findings support its clinical benefits, including low conversion rates, minimal complications, and short hospital stays. Further research, including prospective studies with control groups, is warranted to validate these results and optimize patient outcomes.

Association between pre-diagnostic serum uric acid levels in patients with newly diagnosed epilepsy and conversion rate to drug-resistant epilepsy within 5 years: A common data model analysis

PurposeDrug-resistant epilepsy (DRE) poses a significant challenge in epilepsy management, and reliable biomarkers for identifying patients at risk of DRE are lacking. This study aimed to investigate the association between serum uric acid (UA) levels and the conversion rate to DRE. MethodsA retrospective cohort study was conducted using a common data model database. The study included patients newly diagnosed with epilepsy, with prediagnostic serum UA levels within a six-month window. Patients were categorized into hyperUA (≥7.0 mg/dL), normoUA (<7.0 and >2.0 mg/dL), and hypoUA (≤2.0 mg/dL) groups based on their prediagnostic UA levels. The outcome was the conversion rate to DRE within five years of epilepsy diagnosis. ResultsThe study included 5,672 patients with epilepsy and overall conversion rate to DRE was 19.4%. The hyperUA group had a lower DRE conversion rate compared to the normoUA group (HR: 0.81 [95% CI: 0.69–0.96]), while the hypoUA group had a higher conversion rate (HR: 1.88 [95% CI: 1.38–2.55]). ConclusionsSerum UA levels have the potential to serve as a biomarker for identifying patients at risk of DRE, indicating a potential avenue for novel therapeutic strategies aimed at preventing DRE conversion.

Vegetation–Topographic Landscape and the Influence of Water and Sediment in the Shule River Basin

The study of the effect of vegetation cover on water and sediment content is of great significance for the in-depth understanding of ecological and environmental effects in river basins and the formulation of corresponding management measures. Based on the monitoring data of rainfall and runoff of Panjiazhuang and Dangchengwan Hydrologic Stations in Shule River Basin from 2000 to 2020 and the sediment discharge of Changmabao, methods such as geographic information technology (GIS), landscape pattern analysis, land use transfer matrix, correlation analysis, principal component analysis, and linear regression analysis were used to study water and sediment change, land use pattern, vegetation change characteristics, and local water and sediment change in Shule River Basin and construct vegetation–topographic landscape factors. The main research results are as follows: (1) Vegetation coverage in the Shule River Basin increased year by year from 2000 to 2020, with a cumulative increase of 0.064 in 20 years. Vegetation cover has a significant effect on water and sediment content, and the correlation is −0.966. (2) The cultivated land area of the Shule River Basin increased by 604 km2 from 2000 to 2020, and the conversion rate was 67%. From 2000 to 2020, the water area increased by 442 km2, and the conversion rate was 51%. The area of grassland and forest increased by 198 km2 and 12 km2, respectively, and the conversion rate was 68% and 33%, respectively. Forest had the highest transfer rate (0.67). The lowest conversion rate was 0.32 for grassland. (3) The variation coefficient of water and sediment content in Shule River Basin during 1971–2020 was 45.21%, and the highest variation coefficient during 2001–2010 was 49.15%. The lowest variation coefficient was 39.73% during 2011–2020. The annual sediment transport in the Shule River Basin fluctuates greatly and has a high degree of dispersion during 1971–2020. (4) The results of the landscape index in Shule River Basin during 2000–2020 had a small difference, with a difference of less than 0.5. According to the principal component analysis of landscape index and water and sediment content, the maximum patch index (LPI) had the strongest positive correlation with water and sediment content (0.958). The diversity index SHDI had the strongest negative correlation with water and sediment content (−0.995).

National trends, safety, and effectiveness of minimally invasive concomitant chest wall resection for locally advanced lung cancer

ObjectiveConcomitant chest wall resection for locally advanced lung cancer is traditionally performed via an open approach. The safety and effectiveness of minimally invasive approaches for chest wall resections are unknown. MethodsWe used the National Cancer Database to identify patients undergoing lobectomy/bi-lobectomy with concomitant chest wall resection from 2010 to 2020. We stratified patients into those undergoing a minimally invasive resection (video-assisted thoracoscopic surgery [VATS]/robotic) or open, while accounting for conversions. We also compared VATS with robotic approaches. The main outcomes were length of stay, mortality, readmissions, and overall survival. We used multivariable, Kaplan-Meier and Cox proportional models to identify associations. ResultsOf 2837 patients, 756 procedures (26.6%) were started minimally invasive, of which 23.1% were robotic. There were 237 (31.3%) conversions. Patients undergoing a minimally invasive operation were similar in terms of age (65.2 ± 9.8 years vs 66.0 ± 9.9 years), sex, race, tumor histology, and location (all P > .05) but had smaller cancers (5.4 ± 2.6 cm vs 6.2 ± 4.3 cm; P < .001) compared with those undergoing open. They also had shorter length of stay (8.6 ± 7.6 days vs 9.7 ± 9.3 days; P < .001) but similar unadjusted 90-day mortality (8.2% vs 8.0%; P = .999). Neoadjuvant therapy was associated with less minimally invasive approaches (adjusted odds ratio, 0.69; P ≤ .001). Larger cancers were associated with less minimally invasive operations and greater rates of conversions. However, the robotic approach was associated with lower conversion rates than VATS across all tumor sizes. Overall survival was equivalent. ConclusionsThe use of minimally invasive approaches to concomitant chest wall resection is increasing. Although conversions to open are common, this approach is safe and is associated with shorter hospital stays. Overall survival is equivalent to the open approach.

Improving carbon and nitrogen removal efficiency in high-strength nitrogen wastewater via two-stage nitritation-anammox process

Centralized systems employ biological treatments to remove nutrients, whereas decentralized systems, especially in rural areas, face challenges in implementing them. These systems are low flow but high carbon and nitrogen concentrations, and low C/N ratios. Source-separated wastewater (urine + flush) is an extreme example, like confined animal-feeding wastewater. High nutrient concentrations necessitate innovative technologies typically not employed for decentralized systems. This research demonstrates a simple two-stage nitritation-anammox system to treat high N concentration wastewater (pure urine + flush water). The systems consisted of a Membrane Aerated Biological Reactor (MABR) which performed carbon oxidation and nitritation and novel anammox reactors, (Pancopia AnammoX (PAXs)). The MABRs achieved OC removal over 108–198 g-C/m3-day with ∼ 97% removal, TAN oxidation rates up to 156 g-N/m3-day and nitrite/AN ratios were near 1 with no external control (e.g. pH, DO, cell wasting) other than urine loading rate. The PAXs achieved maximum AN removal efficiencies of 85–97%. The main limitation to complete TN removal in the PAXs was insufficient NO2- in the influent (nonideal influent NO2-/AN ratio). This system was not optimized for energy efficiency and had low volumetric conversion rates compared with other systems. However, it demonstrates that source-separated wastewater can be effectively treated with near complete N removal using a system with minimal process control requirements, lack of solid production, and elimination of diffuse aeration preventing odor generation. These attributes are attractive for applications where conditions do not allow for more complex high-rate systems such as developing societies and rural areas.

Robot-assisted versus laparoscopic pancreatoduodenectomy: a pan-European multicenter propensity-matched study

BackgroundThe use of robot-assisted and laparoscopic pancreatoduodenectomy is increasing, yet large adjusted analyses that can be generalized internationally are lacking. This study aimed to compare outcomes after robot-assisted pancreatoduodenectomy and laparoscopic pancreatoduodenectomy in a pan-European cohort. MethodsAn international multicenter retrospective study including patients after robot-assisted pancreatoduodenectomy and laparoscopic pancreatoduodenectomy from 50 centers in 12 European countries (2009–2020). Propensity score matching was performed in a 1:1 ratio. The primary outcome was major morbidity (Clavien–Dindo ≥III). ResultsAmong 2,082 patients undergoing minimally invasive pancreatoduodenectomy, 1,006 underwent robot-assisted pancreatoduodenectomy and 1,076 laparoscopic pancreatoduodenectomy. After matching 812 versus 812 patients, the rates of major morbidity (31.9% vs 29.6%; P = .347) and 30-day/in-hospital mortality (4.3% vs 4.6%; P = .904) did not differ significantly between robot-assisted pancreatoduodenectomy and laparoscopic pancreatoduodenectomy, respectively. Robot-assisted pancreatoduodenectomy was associated with a lower conversion rate (6.7% vs 18.0%; P < .001) and higher lymph node retrieval (16 vs 14; P = .003). Laparoscopic pancreatoduodenectomy was associated with shorter operation time (446 minutes versus 400 minutes; P < .001), and lower rates of postoperative pancreatic fistula grade B/C (19.0% vs 11.7%; P < .001), delayed gastric emptying grade B/C (21.4% vs 7.4%; P < .001), and a higher R0-resection rate (73.2% vs 84.4%; P < .001). ConclusionThis European multicenter study found no differences in overall major morbidity and 30-day/in-hospital mortality after robot-assisted pancreatoduodenectomy compared with laparoscopic pancreatoduodenectomy. Further, laparoscopic pancreatoduodenectomy was associated with a lower rate of postoperative pancreatic fistula, delayed gastric emptying, wound infection, shorter length of stay, and a higher R0 resection rate than robot-assisted pancreatoduodenectomy. In contrast, robot-assisted pancreatoduodenectomy was associated with a lower conversion rate and a higher number of retrieved lymph nodes as compared with laparoscopic pancreatoduodenectomy.

Perioperative textbook outcomes of minimally invasive pancreatoduodenectomy: a multicenter retrospective cohort analysis in a Korean minimally invasive pancreatic surgery registry.

The aim of this study is to investigate the perioperative composite textbook outcomes of pancreatic surgery after minimally invasive pancreatoduodenectomy (MIPD). The cohort study was conducted across 10 institutions and included 1552 patients who underwent MIPD registered with the Korean Study Group on Minimally Invasive Pancreatic Surgery between May 2007 and April 2020. We analyzed perioperative textbook outcomes of pancreatic surgery after MIPD. Subgroup analyses were performed to assess outcomes based on the hospital volume of MIPD. Among all patients, 21.8% underwent robotic pancreatoduodenectomy. High-volume centers (performing >20 MIPD/year) performed 88.1% of the procedures. The incidence of clinically relevant postoperative pancreatic fistula was 11.5%. Severe complications (Clavien-Dindo grade ≥IIIa) occurred in 15.1% of the cases. The 90-day mortality rate was 0.8%. The mean hospital stay was 13.7 days. Textbook outcomes of pancreatic surgery success were achieved in 60.4% of patients, with higher rates observed in high-volume centers than in low-volume centers (62.2% vs. 44.7%, P<0.001). High-volume centers exhibited significantly lower conversion rates (5.4% vs. 12.5%, P=0.001), lower 90-day mortality (0.5% vs. 2.7%, P=0.001), and lower 90-day readmission rates (4.5% vs. 9.6%, P=0.006) than those low-volume centers. MIPD could be performed safely with permissible perioperative outcomes, including textbook outcomes of pancreatic surgery, particularly in experienced centers. The findings of this study provided valuable insights for guiding surgical treatment decisions in periampullary disease.

Comparison of Prone With Lithotomy Position in Removal of Posterior Myoma in Transvaginal Natural Orifice Endoscopic Surgery: A Prospective Cohort Study

ObjectiveVaginal natural orifice transluminal endoscopic surgery (vNOTES) is considered to have the advantages of completely scarless, less postoperative pain, earlier flatus, and faster postoperative recovery. However, posterior myoma are relatively difficult to operate through vNOTES in the conventional lithotomy position. Thus, we innovated the application of prone position in the removal of posterior myoma in vNOTES. The aim of this study is the comparison of myomectomy outcomes of patient for single posterior myoma in prone and lithotomy position. DesignA single-center, prospective study. SettingA university teaching hospital. PatientsA total of 81 patients with posterior myoma who underwent myomectomy in vNOTES from January 2021 to December 2022. InterventionsThe patients underwent myomectomy in vNOTES in prone or lithotomy position. Measurements and Main ResultsAmong the patients who underwent vNOTES myomectomy, 29 (35.8%) were in the lithotomy position group, and 52 (64.2%) in the prone position group. Of note, 4 (4.9%) patients underwent a conversion to LESS during the operation—3 in the lithotomy and 1 in the prone position group. And a patient in the lithotomy position group underwent resurgery for hemostasis due to postoperative pelvic bleeding. Compared with the lithotomy position, prone position significantly shortens the operation time (12.3, 95% CI: 6.811, 17.761. p = .009) without increasing the complications and postoperative discomfort of patients. ConclusionCompared to the lithotomy position, the prone position provides greater convenience for operation and exhibits a lower rate of surgical conversion during the removal of single posterior myomas via vNOTES. Further, for patients selecting vNOTES, surgeons need to conduct sufficient preoperative evaluation, timely hemostasis during surgery, and timely surgical conversion if necessary to ensure patient safety.