Low Conversion Rate Research Articles

Robotic Vascular Resection in Pancreatic Ductal Adenocarcinoma: A Systematic Review.

(1) Background: This study comprehensively compared robotic pancreatic surgery with vascular resection (RPS-VR) to other surgical procedures in the treatment of pancreatic ductal adenocarcinoma (PDAC). (2) Methods: A systematic review of relevant literature was conducted to assess a range of crucial surgical and oncological outcomes. (3) Results: Findings indicate that robotic surgery with vascular resections (VRs) significantly prolongs the duration of surgery compared to other surgical procedures, and they notably demonstrate an equal hospital stay. While some studies reported a lower conversion rate and a higher rate of blood loss and blood transfusion in the RPS-VR group, others found no significant disparity. Furthermore, RPS-VR consistently correlated with comparable recurrence rates, free margins R0, postoperative mortality, and complication rates. Concerning the last one, certain reviews reported a higher rate of major complications. Overall survival and disease-free survival remained comparable between the RPS-VR and other surgical techniques in treating PDAC. (4) Conclusions: The analysis emphasizes how RPS-VR is a resembling approach in terms of surgical outcomes and aligns with existing literature findings in this field.

The promoting and inhibitory mechanism of interaction between waste tires and Spirulina on their co-pyrolysis

Energy utilization of biomass and waste is an important thrust for carbon emission reduction. Co-pyrolysis is conductive to efficiently converting algae and waste tires, due to their complementary pyrolysis characteristics. However, the influence of the interaction between algae and waste tires on co-pyrolysis behavior is still controversial, due to the internal mechanism of interaction is unclear. Therefore, in this study, mechanism experiments and theoretical calculations were used to comprehensively investigate the interaction mechanism between Spirulina (SP) and waste tires (WT). The co-pyrolysis of SP and WT can be divided into two main steps: low-temperature SP decomposition and high-temperature WT decomposition. The activation energies of WT and mixture increase with the conversion rate, while those of SP change little at low conversion rates (<60 %). The pyrolysis activation energies of mixture are lower than the theoretical values, as the blending ratio of SP below 50 %. The interaction between SP and WT has both promoting and inhibiting effects on the pyrolysis of mixture. The attack of free radicals from SP pyrolysis and ash in WT promotes the pyrolysis of mixture, but the low-temperature polymerization reactions and high-temperature aromatization reactions inhibit the release of pyrolysis products. The formation of benzene compound is promoted due to the attack of free radicals and the polymerization between SP and WT.

Long-Term Outcomes of Robotic Versus Laparoscopic Total Mesorectal Excisions: A Propensity-Score Matched Cohort study of 5-year survival outcomes.

To compare long-term outcomes between laparoscopic and robotic total mesorectal excisions (TMEs) for rectal cancer in a tertiary center. Laparoscopic rectal cancer surgery has comparable long-term outcomes to the open approach, with several advantages in short-term outcomes. However, it has significant technical limitations, which the robotic approach aims to overcome. We included patients undergoing laparoscopic and robotic TME surgery between 2013 and 2021. The groups were compared after propensity-score matching. The primary outcome was 5-year overall survival (OS). Secondary outcomes were local recurrence (LR), distant recurrence (DR), disease-free survival (DFS), and short-term surgical and patient-related outcomes. A total of 594 patients were included, and after propensity-score matching 215 patients remained in each group. There was a significant difference in 5-year OS (72.4% for laparoscopy vs 81.7% for robotic, P = 0.029), but no difference in 5-year LR (4.7% vs 5.2%, P = 0.850), DR (16.9% vs 13.5%, P = 0.390), or DFS (63.9% vs 74.4%, P = 0.086). The robotic group had significantly less conversion (3.7% vs 0.5%, P = 0.046), shorter length of stay [7.0 (6.0-13.0) vs 6.0 (4.0-8.0), P < 0.001), and less postoperative complications (63.5% vs 50.7%, P = 0.010). This study shows a correlation between higher 5-year OS and comparable long-term oncological outcomes for robotic TME surgery compared to the laparoscopic approach. Furthermore, lower conversion rates, a shorter length of stay, and a less minor postoperative complications were observed. Robotic rectal cancer surgery is a safe and favorable alternative to the traditional approaches.

Alkaline earth metal modified La-Fe based perovskite enhances hydroxyl radicals for efficient coke cleaning

The low conversion rate of coke during online coke cleaning is due to the stable structure of graphite carbon, which makes it difficult to react with steam. Therefore, there is an urgent need to design a catalyst for catalytic graphite carbon conversion to achieve efficient in situ coke cleaning. Alkaline earth metal Sr modified La-Fe based perovskite LSF-x (x = 0, 0.2, 0.4, 0.6, 0.8, 1) were prepared by hydrothermal method. DFT and experimental results indicate that doping Sr at the A-site reduces the adsorption energy barrier of water molecules, promotes the decomposition of water molecules to produce absorbed and free hydroxyl radicals, and thereby enhances the conversion of graphite carbon. At 900 °C, a catalytic coke conversion of 97.32% in the presence of La0.2Sr0.8FeO3 was achieved, which was 2.09 times the value without a catalyst. The research results provide a certain theoretical basis for catalytic heterogeneous reactions.

Tibial plateau fractures are associated with poor functional outcomes and a low conversion rate to total knee arthroplasty.

The aim of this study was to analyse the functional outcome and the conversion rate to total knee arthroplasty (TKA) after surgically treated tibial plateau fractures (TPF). All patients undergoing surgical treatment of TPF at a single institution between January 2003 and December 2019 were retrospectively reviewed. The Knee injury and Osteoarthritis Outcome Score (KOOS) and Tegner activity scale (TAS) were collected. The conversion rate to TKA was examined 2, 5, 7 and 10 years after surgical treatment of TPF. Ninety-four patients, with a mean follow-up of 110.6 months (±60.0), were included in the functional outcome assessment. Mean KOOS scores were 75.4 for symptoms, 80.6 for pain, 84.3 for activities of daily living (ADL), 59.5 for sports and 61.3 for QOL. All subscales were significantly lower on the injured side compared with the contralateral leg. Lower KOOS was observed in patients with hardware removal and Schatzker type 5 and 6 injuries. Median TAS was postinjury (4) significantly lower than preinjury (5) (p < 0.001). The conversion rate to TKA was 6.3%, 10.9%, 11.7% and 12.2% after 2,5,7 and 10 years of follow-up, respectively. Patients undergoing TKA were older than patients with no conversion to TKA (2 years follow-up 53.8 vs. 64.5 years, p = 0.026). TPFs decrease the function of the knee when compared with the contralateral side and to the preoperative condition. Bicondylar fractures are associated with worse functional outcomes. A conversion rate to TKA of 12.2% was found at 10 years follow-up. Level III.

Changes in chemical components and hepatoprotective effect of red Panax notoginseng processed by aspartic acid impregnation treatment.

Red Panax notoginseng (RPN) is one of the major processed products of P. notoginseng (PN), with more effective biological activities. However, the traditional processing method of RPN has some disadvantages, such as low conversion rate of ginsenosides and long processing time. In this work, we developed a green, safe, and efficient approach for RPN processing by aspartic acid impregnation pretreatment. Our results showed that the optimized temperature, steaming time, and concentration of aspartic acid were 120 °C, 1 h, and 3% respectively. The original ginsenosides in PN treated by aspartic acid (Asp-PN) were completely converted to rare saponins at 120 °C within just 1 h. The concentration of the rare ginsenosides in Asp-PN was two times higher than that in untreated RPN. In addition, we examined the protective effect of RPN and Asp-PN on acetaminophen-induced liver injury in a mouse model. The results showed that Asp-PN has significantly more potent hepatoprotective action than the RPN. The hepatoprotection of Asp-PN in acetaminophen-induced hepatotoxicity may be due to its anti-oxidative stress, anti-apoptotic, and anti-inflammatory activities. These results indicated that aspartic acid impregnation pretreatment may provide an effective method to shorten the steaming time, improve the conversion rate of ginsenosides, and enhance hepatoprotective activity of RPN. © 2024 Society of Chemical Industry.

Comparing oncologic and surgical outcomes of robotic and laparoscopic pancreatoduodenectomy in patients with pancreatic cancer: a propensity-matched analysis.

Minimally invasive Pancreatoduodenectomy (MIPD), or the Whipple procedure, is increasingly utilized. No study has compared laparoscopic (LPD) and robotic (RPD) approaches, and the impact of the learning curve on oncologic, technical, and post-operative outcomes remains relatively understudied. The National Cancer Database was queried for patients undergoing LPD or RPD from 2010 to 2020 with a diagnosis of pancreatic cancer. Outcomes were compared between approaches using propensity-score matching (PSM); the impact of annual center-level volume of MIPD was also assessed by dividing volume into quartiles. A total of 3,342 patients were included. Most (n = 2,716, 81.3%) underwent LPD versus RPD (n = 626, 18.7%). There was a high rate (20.2%, n = 719) of positive margins. Mean length-of-stay (LOS) was 10.4 ± 8.9days. Thirty-day mortality was 2.8% (n = 92) and ninety-day mortality was 5.7% (n = 189). PSM matched 625 pairs of patients receiving LPD or RPD. After PSM, there was no differences between groups based on age, sex, race, CCI, T-stage, neoadjuvant chemo/radiotherapy, or type of PD. After PSM, there was a higher rate of conversion to open (HR = 0.68, 95%CI = 0.50-0.92)., but there was no difference in LOS (HR = 1.00, 95%CI = 0.92-1.11), 30-day readmission (HR = 1.08, 95% CI = 0.68-1.71), 30-day (HR = 0.78, 95% CI = 0.39-1.56) or 90-day mortality (HR = 0.70, 95% CI = 0.42-1.16), ability to receive adjuvant therapy (HR = 1.15, 95% CI = 0.92-1.44), nodal harvest (HR = 1.01, 95%CI = 0.94-1.09) or positive margins (HR = 1.19, 95% CI = 0.89-1.59). Centers in lower quartiles of annual volume of MIPD demonstrated reduced nodal harvest (p = 0.005) and a higher rate of conversion to open (p = 0.038). Higher-volume centers had a shorter LOS (p = 0.012), higher rate of initiation of adjuvant therapy (p = 0.042), and, most strikingly, a reduction in 90-day mortality (p = 0.033). LPD and RPD have similar surgical and oncologic outcomes, with a lower rate of conversion to open in the robotic cohort. The robotic technique does not appear to eliminate the "learning curve", with higher volume centers demonstrating improved outcomes, especially seen at minimum annual volume of 5 cases.

Biosynthesis of mannose from glucose via constructing phosphorylation-dephosphorylation reactions in Escherichia coli

d-mannose has been widely used in food, medicine, cosmetic, and food-additive industries. To date, chemical synthesis or enzymatic conversion approaches based on iso/epimerization reactions for d-mannose production suffered from low conversion rate due to the reaction equilibrium, necessitating intricate separation processes for obtaining pure products on an industrial scale. To circumvent this challenge, this study showcased a new approach for d-mannose synthesis from glucose through constructing a phosphorylation-dephosphorylation pathway in an engineered strain. Specifically, the gene encoding phosphofructokinase (PfkA) in glycolytic pathway was deleted in Escherichia coli to accumulate fructose-6-phosphate (F6P). Additionally, one endogenous phosphatase, YniC, with high specificity to mannose-6-phosphate, was identified. In ΔpfkA strain, a recombinant synthetic pathway based on mannose-6-phosphate isomerase and YniC was developed to direct F6P to mannose. The resulting strain successfully produced 25.2 g/L mannose from glucose with a high conversion rate of 63% after transformation for 48 h. This performance surpassed the 15% conversion rate observed with 2-epimerases. In conclusion, this study presents an efficient method for achieving high-yield mannose synthesis from cost-effective glucose.

Consumer insights into the at-home liking of commercial beers: Integrating nonvolatile and volatile flavor chemometrics.

Consumer acceptability of beers is influenced by product formulation and processing conditions, which impart unique sensory profiles. This study used multivariate techniques to evaluate at-home consumer sensory acceptability of six commercial beers considering their style, fermentation type, and chemical composition. Samples included top-fermented beers (American India Pale Ale and Stout) and bottom-fermented beers (Pilsner, zero-alcohol Pilsner, Vienna Lager, and Munich Dunkel). Beer consumers (n = 50) conducted sensory hedonic, check-all-that-apply (CATA) and just-about-right (JAR) tests. Chemometric variables included iso-alpha-acids, hordenine, and volatile aromatic compounds, quantified by chromatographic methods, whereas bitterness units (IBU) were determined spectrophotometrically. Lager beers had higher acceptability than top-fermented beer (p < .05) for all attributes. Light-colored beers and medium-height foams had the highest liking scores for visual sensory attributes. Higher concentrations of bitter-tasting molecules, hordenine, and acidity decreased the liking scores of top-fermented (Ale) beers, as a sensory penalty analysis suggested. In contrast, the most favored beers (Pilsners and Munich Dunkel) contained higher fusel alcohol esters linked to fruity aromatic notes. Although a low conversion rate of fatty acids into fruity esters was noted in nonalcoholic Pilsner, its overall liking score was not statistically different from the alcoholic version. However, consumers perceived the nonalcoholic Pilsner as less bitter than its alcoholic counterpart even when IBUs were nonsignificantly different. This study emphasized the significance of understanding beer chemometrics to comprehend consumer acceptability, highlighting the crucial role of bitter molecules. Hence, hordenine, acidity, and volatile contents provided additional and valuable insights into consumer preferences.

Length effect of short base resin on thermomechanical properties of crosslinked epoxy resin via molecular dynamics simulation

Epoxy resin is commonly used as the matrix in carbon fiber-reinforced polymer (CFRP), fabricated through the curing reaction of the base resin and curing agent, whose properties have a deep relationship with the crosslinking degree of the polymer. However, under certain circumstances, the desired conversion rate cannot be achieved in the experiments. To shed light on this phenomenon and the underlying mechanisms, the curing process of diglycidyl ether of bisphenol A (DGEBA) with different chain lengths and 4,4′-diamino diphenyl sulfone (4,4′-DDS) was simulated as per our previously developed crosslinking algorithm. The longer chain length postpones but does not change the reaction progress (like the gel point), leading to a lower conversion rate, and ultimately a decrease in the diffusion coefficient. In addition, the influence on the glass transition temperature is the result of the competing effects of the conversion rate and monomer diffusivity. Moreover, the negligible effect on thermal conductivity is closely linked with a slight change in the monomeric degree index (MDI), reflecting the whole internal intrinsic structure. Furthermore, the effect on Young's modulus and yield stress has a deep relationship with the ring degree index (RDI), i.e., higher RDI demands more non-bonded energy for the collective movement of monomer chains. Our systematic investigation unifies the mechanism of the impact of chain length on various thermomechanical properties, which is instructive for the improved performance of epoxy resins.

Farm factors influencing spatial variations of cropland use and change in the context of urban expansion: The case of Jimma City, Southwest Ethiopia

Urban factors comprising economic and population growth are widely discussed as determinants of cropland-use change decisions and urbanization containment. Despite the academic discussion, farm factors remain detached from urban planning theories and practices. This study used a cross-sectional survey and remote sensing data to investigate farm factors influencing farmers’ cropland-use decisions. To measure human farm factors, a structured questionnaire was used to collect quantitative data from a randomly selected 300 farmers in Jimma peri-urban areas while an unstructured questionnaire was used to gather views of conveniently recruited participants. Landsat-8 and the Digital Elevation Model (DEM) were employed to extract the physical factors. The Ordinary Least Squares (OLS) model was used to determine significant farm factors of cropland-use decisions and the Geographical Weighted Regression (GWR) model was applied to map the spatial variation in cropland-use decisions along the rural-urban continuum. The results revealed that farm factors influenced the cropland-use decisions of farmers. Cropland-use conversion rates increase with distance to the urban center due to greater access to social services. The conversion rates also increase with decreasing slope gradients and good soil quality. Farmers with higher farm income, labour, and extension have lower cropland-use conversion rates while those with higher non-farm income and labour, family size, farm size, and education have higher conversion rates. The findings of this study suggest that government policies aimed at restricting urban growth and sustaining ecosystem services should adopt farm factors to preserve prime cropland-use along the rural-urban continuum. Considering farm factors in urban land-use planning also promotes synergistic rural-urban planning integrations to bring balanced rural-urban development, poverty reduction, slow urban migration, and smart urban growth.

Robotic-assisted versus conventional laparoscopic surgery in the management of obese patients with early endometrial cancer in the sentinel lymph node era: a randomized controlled study (RObese)

BackgroundNearly 65% of patients with endometrial cancer who undergo primary hysterectomy have concurrent obesity. Retrospective data show advantages in using robotic surgery in these patients compared with conventional laparoscopy, namely...

Fellow Eyes Conversion Rates in Patients With Unilateral Exudative Age-Related Macular Degeneration: An Academy IRIS® Registry Analysis.

This study aimed to examine conversion rates from non-exudative to exudative age-related macular degeneration (AMD) in the fellow eye of patients with unilateral exudative AMD using the Academy IRIS® Registry. This study was a retrospective, cohort analysis from 2016 to 2019. Patient and disease characteristics including initial AMD stage were collected. Cox proportional-hazard (PH) and logistic regression modeling were performed. The risk of conversion was lower for men relative to women and for Asians and Blacks relative to Whites. Compared to never-smokers, active smokers were at increased risk of conversion, and compared to initially early non-exudative AMD eyes, intermediate and advanced non-exudative AMD eyes had higher rates of conversion. Compared to active choroidal neovascularization eyes, eyes with inactive choroidal neovascularization and inactive scars had lower rates of fellow eye conversion. In this cohort analysis of unilateral exudative AMD patients, women, Whites, and active smokers had higher rates of non-exudative to exudative AMD conversion in the fellow eye. [Ophthalmic Surg Lasers Imaging Retina 2024;55:220-226.].

Meta-analysis of randomized clinical trials comparing robotic versus laparoscopic surgery for mid-low rectal cancers

Robotic surgery (RS) is experiencing major development, particularly in the context of rectal cancer. The aim of this meta-analysis was to summarize data from the literature, focusing specifically on the safety and effectiveness of robotic surgery in mid-low rectal cancers, based on the hypothesis that that robotic surgery can find its most rational indication in this anatomical location. The meta-analysis was conducted according to the PRISMA 2000 recommendations, including all randomized trials that compared robotic surgery versus laparoscopic surgery (LS) that were found in the Medline-PICO, Cochrane Database, Scopus and Google databases. Data were extracted independently by two reviewers. The risk of bias was analyzed according to the Cochrane Handbook method and the certainty of the evidence according to the GRADE method. The analysis was carried out with R software Version 4.2-3 using the Package for Meta-Analysis "meta" version 6.5-0. Eight randomized trials were included (with a total of 2342 patients), including four that focused specifically on mid-low rectal cancer (n=1,734 patients). No statistically significant difference was found for overall morbidity, intra-operative morbidity, anastomotic leakage, post-operative mortality, quality of mesorectal specimen, and resection margins. The main differences identified were a lower conversion rate for RS (RR=0.48 [0.24-0.95], p=0.04, I2=0%), and a longer operative time for RS (mean difference=39.11min [9.39-68.83], p<0.01, I2=96%). The other differences had no real clinical relevance, i.e., resumption of flatus passage (5hours earlier after RS), and lymph node dissection (one more lymph node for LS). This meta-analysis does not confirm the initial hypothesis and does not show a statistically significant or clinically relevant benefit of RS compared to LS for mid-low rectal cancer.

Early experience with robotic pancreatoduodenectomy versus open pancreatoduodenectomy: nationwide propensity-score-matched analysis.

Although robotic pancreatoduodenectomy has shown promising outcomes in experienced high-volume centres, it is unclear whether implementation on a nationwide scale is safe and beneficial. The aim of this study was to compare the outcomes of the early experience with robotic pancreatoduodenectomy versus open pancreatoduodenectomy in the Netherlands. This was a nationwide retrospective cohort study of all consecutive patients who underwent robotic pancreatoduodenectomy or open pancreatoduodenectomy who were registered in the mandatory Dutch Pancreatic Cancer Audit (18 centres, 2014-2021), starting from the first robotic pancreatoduodenectomy procedure per centre. The main endpoints were major complications (Clavien-Dindo grade greater than or equal to III) and in-hospital/30-day mortality. Propensity-score matching (1 : 1) was used to minimize selection bias. Overall, 701 patients who underwent robotic pancreatoduodenectomy and 4447 patients who underwent open pancreatoduodenectomy were included. Among the eight centres that performed robotic pancreatoduodenectomy, the median robotic pancreatoduodenectomy experience was 86 (range 48-149), with a 7.3% conversion rate. After matching (698 robotic pancreatoduodenectomy patients versus 698 open pancreatoduodenectomy control patients), no significant differences were found in major complications (40.3% versus 36.2% respectively; P = 0.186), in-hospital/30-day mortality (4.0% versus 3.1% respectively; P = 0.326), and postoperative pancreatic fistula grade B/C (24.9% versus 23.5% respectively; P = 0.578). Robotic pancreatoduodenectomy was associated with a longer operating time (359 min versus 301 min; P < 0.001), less intraoperative blood loss (200 ml versus 500 ml; P < 0.001), fewer wound infections (7.4% versus 12.2%; P = 0.008), and a shorter hospital stay (11 days versus 12 days; P < 0.001). Centres performing greater than or equal to 20 robotic pancreatoduodenectomies annually had a lower mortality rate (2.9% versus 7.3%; P = 0.009) and a lower conversion rate (6.3% versus 11.2%; P = 0.032). This study indicates that robotic pancreatoduodenectomy was safely implemented nationwide, without significant differences in major morbidity and mortality compared with matched open pancreatoduodenectomy patients. Randomized trials should be carried out to verify these findings and confirm the observed benefits of robotic pancreatoduodenectomy versus open pancreatoduodenectomy.

Thirteen Years of Impactful, Minimally Invasive Coronary Surgery: Short- and Long-Term Results for Single and Multi-Vessel Disease

Objectives: Minimally invasive coronary surgery (MICS) via lateral thoracotomy is a less invasive alternative to the traditional median full sternotomy approach for coronary surgery. This study investigates its effectiveness for short- and long-term revascularization in cases of single and multi-vessel diseases. Methods: A thorough examination was performed on the databases of two cardiac surgery programs, focusing on patients who underwent minimally invasive coronary bypass grafting procedures between 2010 and 2023. The study involved patients who underwent either minimally invasive direct coronary artery bypass grafting (MIDCAB) for the revascularization of left anterior descending (LAD) artery stenosis or minimally invasive multi-vessel coronary artery bypass grafting (MICSCABG). Our assessment criteria included in-hospital mortality, long-term mortality, and freedom from reoperations due to failed aortocoronary bypass grafts post-surgery. Additionally, we evaluated significant in-hospital complications as secondary endpoints. Results: A total of 315 consecutive patients were identified between 2010 and 2023 (MIDCAB 271 vs. MICSCABG 44). Conversion to median sternotomy (MS) occurred in eight patients (2.5%). The 30-day all-cause mortality was 1.3% (n = 4). Postoperative AF was the most common complication postoperatively (n = 26, 8.5%). Five patients were reoperated for bleeding (1.6%), and myocardial infarction (MI) happened in four patients (1.3%). The mean follow-up time was six years (±4 years). All-cause mortality was 10.3% (n = 30), with only five (1.7%) patients having a confirmed cardiac cause. The reoperation rate due to graft failure or the progression of aortocoronary disease was 1.4% (n = 4). Conclusions: Despite the complexity of the MICS approach, the results of our study support the safety and effectiveness of this procedure with low rates of mortality, morbidity, and conversion for both single and multi-vessel bypass surgeries. These results underscore further the necessity to implement such programs to benefit patients.

Double enzymes coupled screening assisted molecular modification of α-Amino acid ester acyltransferase for L-Alanyl-l-Glutamine biosynthesis

L-Alanyl-l-Glutamine (Ala-Gln) is a kind of functional dipeptide, which is widely used in food and health care. Ala-Gln can be synthesized from l-glutamine and l-alanine methyl ester hydrochloride by α-Amino acid ester acyltransferase (AET). Still, the low catalytic efficiency and conversion rate of AET are key limiting factors in Ala-Gln production. In this study, the mutant library of AET were built based on structural model and semi-rational design. To facilitate the screening of AET mutants, the double enzymes coupled screening method was constructed and optimized. The amino acid residues I115, D203, F211, D300, A298, and R334 were selected as candidate mutation sites by alanine scanning and virtual saturation mutation and the catalytic activity of the optimal mutation A298C increased by 23.7%. Molecular dynamics simulation and molecular docking analysis suggested that the increased flexibility of the catalytic pocket in AET (A298C) and the formation of additional hydrogen bonds with substrate contributed to the improvement of enzyme activity.

Enhanced bacterial cellulose production in Gluconacetobacter xylinus by overexpression of two genes (bscC and bcsD) and a modified static culture

Bacterial cellulose (BC), a nanostructured material, is renowned for its excellent properties. However, its production by bacteria is costly due to low medium utilization and conversion rates. To enhance the yield of BC, this study aimed to increase BC yield through genetic modification, specifically by overexpressing bcsC and bcsD in Gluconacetobacter xylinus, and by developing a modified culture method to reduce medium viscosity by adding water during fermentation. As a result, BC yields of 5.4, 6.2, and 6.8 g/L were achieved from strains overexpressing genes bcsC, bcsD, and bcsCD, significantly surpassing the yield of 2.2 g/L from wild-type (WT) strains. In the modified culture, the BC yields of all four strains increased by >1 g/L with the addition of 20 mL of water during fermentation. Upon comparing the properties of BC, minimal differences were observed between the WT and pbcsC strains, as well as between the static and modified cultures. In contrast, BC produced by strains overexpressing bcsD had a denser microstructural network and exhibited demonstrated higher tensile strength and elongation-to-break. Compared to WT, BC from bcsD overexpressed strains also displayed enhanced crystallinity, higher degree of polymerization and improved thermal stability.

Continuous Flow System for Highly Efficient and Durable Photocatalytic Oxidative Coupling of Methane.

Photocatalytic oxidative coupling of methane (OCM) into value-added industrial chemicals offers an appealing green technique for achieving sustainable development, whereas it encounters double bottlenecks in relatively low methane conversion rate and severe overoxidation. Herein, we engineer a continuous gas flow system to achieve efficient photocatalytic OCM while suppressing overoxidation by synergizing the moderate active oxygen species, surface plasmon-mediated polarization, and multipoint gas intake flow reactor. Particularly, a remarkable CH4 conversion rate of 218.2 μmol h-1 with an excellent selectivity of ∼90% toward C2+ hydrocarbons and a remarkable stability over 240 h is achieved over a designed Au/TiO2 photocatalyst in our continuous gas flow system with a homemade three-dimensional (3D) printed flow reactor. This work provides an informative concept to engineer a high-performance flow system for photocatalytic OCM by synergizing the design of the reactor and photocatalyst to synchronously regulate the mass transfer, activation of reactants, and inhibition of overoxidation.

Comparison of treatment methods in plastron appendicitis: a tertiary center experience.

It is controversial which treatment method is superior in plastron appendicitis and the research is still going on. The aim of this study is to compare treatment methods for plastron appendicitis in the adult population with our experience. The data of 92 patients who were diagnosed with plastron appendicitis in university hospital between 2015 and 2021 were analyzed retrospectively. Data were taken from the hospital database. The patients were divided into three groups: those treated with primary surgery, with interval appendectomy and only with conservative method. Interval appendectomy resulted in a lower rate of conversion to open surgery compared to primary surgery, shorter operative time, and lower complication rates. Surgical procedures were found to be superior in detecting neoplasms compared to conservative treatment. After conservative treatment, one of three patients was retreated with the diagnosis of acute appendicitis. In plastron appendicitis, routine interval appendectomy can be performed due to its advantages over other treatments such as the frequency of attacks after conservative treatment, the risk of the tumor being overlooked in conservative treatment, and the high rate of complications and conversion to open surgery in the primary surgery group.