Piece Of Membrane Research Articles

A humidity resistant radon source developed by ion exchange of radium in a membrane

ObjectiveTo develop a humidity resistant radon source on a membrane based on the ion exchange technique. Methods226Ra in its standard solution was adsorbed in the HP membrane through cation exchange. The radioactivity of 226Ra in the membrane was determined through the measurements of 226Ra activities in the solution before and after the adsorption using a HPGe γ spectrometer. The emanation coefficients of radon from the membrane in different humidity conditions were quantified through the measurements of radon concentrations in a close loop mode using the AlphaGUARD DF2000 radon monitor. Long-term measurements of radon concentrations in the close loop and a standard chamber using the membrane as radon source were performed to verify the stability of radon emanation from the source. ResultsA piece (70 ​mm ​× ​20 ​mm) of the HP membrane could adsorb 51.2 kBq of 226Ra in about 30 ​min. The emanation coefficient of radon from the membrane could reach as high as 0.997, and it was hardly changed in a humidity range from 7.5% RH to 94.5 ​% RH. The variation of the radon production rate from the source was only ±1.2 ​% in two weeks at a general laboratory condition, and its emanation stability was also confirmed in a standard radon chamber by using the membrane source for one month. ConclusionThe radon membrane source developed in this study has a stable emanation coefficient regardless the environmental humidity. It can be used as a flow-through radon source in a standard radon chamber.

Sustainability-Driven Accelerated Shear-Mediated Immunoassay for Amyotrophic Lateral Sclerosis Detection.

Healthcare facilities produce millions of tons of waste annually, with a significant portion consisting of diagnostic plasticware. Here, we introduce a new detection platform that completely replaces traditional assay plates with a piece of membrane, offering a much greener and more sustainable alternative. The membrane, integrated within the portable vortex fluidic device (P-VFD), enables rapid detection of a clinically relevant protein biomarker, urinary p75ECD. This biomarker is utilized to evaluate the prognosis, disease severity, and progression of amyotrophic lateral sclerosis (ALS). This assay has a limit-of-detection (LOD) of 4.03 pg, which is comparable to the plate-based assay (2.24 pg) and has been optimised through a full factorial design of experiments (DOE) and response surface methodology (RSM). P-VFD has great potential in quantifying p75ECD in human biofluids and can significantly reduce the assay time to 5 min compared to the current plate-based p75ECD ELISA assay (3 days), with at least a 4.4-fold reduction in the usage of the detection antibody.

Removal of Micropollutants in Water Reclamation by Membrane Filtration: Impact of Pretreatments and Adsorption.

Organic micropollutants (OMPs) present in water and wastewater are in the spotlight because of their potentially harmful effects even at low concentrations and the difficulties of their elimination in urban wastewater treatment plants (UWWTPs). This study explores the impact of some membrane filtration processes on the removal of a group of 11 OMPs with an eye on the effects of two pretreatments (i.e., coagulation and adsorption onto powdered activated carbon (PAC)) and the adsorption of OMPs onto the membranes on the overall removal. For this purpose, ultrafiltration (UF) and nanofiltration (NF) experiments were conducted with selected OMPs spiked in ultrapure water and secondary effluents from UWWTPs. It was observed that the adsorption of OMPs onto the membranes was influenced by the characteristics of the membranes, as well as the presence of effluent organic matter (EfOM). Since adsorption was the dominant mechanism for the rejection of OMPs by UF membranes, a study of the adsorption equilibrium of the micropollutants using UF membrane pieces as the adsorbent was conducted. The adsorption isotherms for the most hydrophobic OMPs fitted the Langmuir model. The efficiency of coagulation and powdered activated carbon (PAC) adsorption coupled with UF were also investigated. Both pretreatments alleviated membrane fouling and improved the rejection of organic and inorganic matter. The PAC pretreatment significantly improved the removal of OMPs in the combined PAC/UF process. The best options for achieving reclaimed water with satisfactory physicochemical quality, nearly devoid of OMPs and microorganisms, and suitable for diverse reuse purposes are either the NF treatment or the combination of PAC/UF.

#2834 Analysis of cyst hetero- and homogeneity to unravel common pathways in autosomal dominant polycystic kidney disease

Abstract Background and Aims Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease, with a prevalence of 1 in ca. 1000 individuals and accounting for 10% of the European dialysis population. It is most frequently (75-80%) caused by mutations in the PKD1 gene encoding Polycystin-1. Besides systemic manifestations such as liver cysts, hypertension and cardiac abnormalities, the most prominent phenotype is the gradual development of kidney cysts, leading to kidney enlargement and a decline in kidney function leading to end-stage kidney disease at an average age of ca. 50 years. The cysts arise from tubular epithelial cells in the nephron that start to dedifferentiate, proliferate and eventually secrete fluid into the cyst lumen promoting its swelling. This process is molecularly regulated by changes in Ca2+, cAMP, PKA and PI3K-Akt-mTOR signaling, among others. The renal cysts are further characterized by ciliary dysfunction, altered signal transduction, loss of polarity, apoptosis, mitochondrial abnormalities, metabolic reprogramming, inflammation, oxidative stress and epigenetic changes. However, the exact sequence of events and their relative importance in the process of cyst formation remains unclear. Therefore, we analyzed the transcriptomic cyst hetero- and homogeneity to identify the pathways that were different, but also shared among individual cysts. Method We performed RNA-Seq analysis on 40 individual cystic membranes of nephrectomized kidneys of 4 PKD1 patients. We included 4 samples of macroscopically healthy tissue from 2 ADPKD kidneys (histologically confirmed to have microcysts) and 4 samples from 4 healthy kidneys. Principal component, cluster and trajectory analysis was performed to explore cyst heterogeneity. Adjacent pieces of cystic membrane were analyzed for histology (H&E, Sirius Red) or stained with FITC-tagged Lotus Tetragonolobus Lectin (LTL) or Dolichos Biflorus Agglutinin (DBA), a proximal and distal tubular marker, respectively. Results Although the cysts clearly separated from the healthy tissues in the analyses, there was also a distinct heterogeneity observed among the cysts that was independent of patient, gender, cyst size, location or fluid color. Pathway analysis revealed that these changes were characterized by a gradual increase of interstitial (remodeling) and inflammation markers, and a gradual decrease in differentiation markers (e.g. development, intercellular junctions, basement membrane) along the trajectory pseudotime. We could identify 6 clusters of cystic samples, with 2 clusters deviating from the main trajectory. With respect to tubular/epithelial dedifferentiation, the decrease in proximal tubular markers already occurred in microcystic tissue and was stronger compared to the other tubular segments. Consequently, none of the analyzed cystic membranes stained positive for LTL, while others showed clear staining for DBA. Microcysts on the other hand stained positive for LTL or DBA. Several cysts showed RNA marker expression of multiple tubular segments. Indeed, smaller macrocysts (diameter in the mm range) were lined by both LTL- and DBA-positive regions. Conclusion By analyzing transcriptomic hetero- and homogeneity among individual cysts, the molecular alterations in ADPKD progression can be tracked down and determined whether they occur similarly in all cysts or at different levels. Our data also suggest that loss of proximal tubular markers in macrocysts is more prominent compared to the decrease in distal markers. Finally, inner cyst walls can consist of cyst-lining cells of multiple origins.

Constituents of Coliform Species Contained in the Permeate of Microfiltration Membranes in Wastewater Treatment

MBRs (Membrane bioreactors) have been increasingly employed for municipal and industrial wastewater treatment in the last decades for their small footprint and excellent effluent quality. However, microorganisms are often detected in the permeates of microfiltration (MF) membranes even with small pore sizes. Coliform bacteria are known for indicating the potential presence of pathogenic bacteria that cause infectious disease such as bacteremia, respiratory tract infections, and urinary tract infections. Thus, the retention of coliform bacteria by membrane processes is important when the membrane process is utilized in water reclamation. In this study, a microbial community of coliform bacteria in the permeates of MF membranes with different pore sizes (0.2, 0.4, and 0.8 µm) was identified. The results showed that the dominant coliform bacteria changed from Enterobacter spp. and Citrobacter spp. in the activated sludge to Enterobacter spp. and Klebsiella spp. in the permeate of MF membranes, while some pieces of membranes showed complete retention. The bacterial regrowth on the surface of the piping system on the permeate side could be a significant factor contributing to the frequent and exclusive detection of Enterobacter spp. and Klebsiella spp. in the case of membranes with small pore size (0.2 and 0.4 µm) after a long continuous filtration time. To indicate the public health-related risk of treated wastewater by MF, Escherichia coli may not be a suitable indicator species because E. coli is relatively retentive in MF compared to other coliforms.

Modeling and study of pressure-dependent boiling crisis in membrane-based heat sink

A theoretical model is developed to study the pressure-dependent boiling crisis of membrane-based heat sink. It has been reported that the critical heat flux of this heat sink can be increased to 1.8 kW/cm2 by using a piece of hydrophobic membrane to promote bubble departure. In the modeling, two boiling crisis mechanisms are applied. The free energy and the forces acting on the bubble are considered in the calculations of the bubble's geometric dimensions, the vapor venting rate, and the pressure drop for driving the wicking flow. Wetting and the evaporating rate beneath the bubble are computed based on the reported coupled wicking and evaporation model. The modeling explains why there exist two regions in the profile of the critical heat flux against the pressure drop. The time for rewetting the dry spot is obtained with the modeling to establish the correlation between the critical heat flux and the pressure drop at higher heat flux. When the boiling surface has a relatively high area ratio, the modeling error is 3 % with the suggested membrane permeability and critical temperature rise of the dry spot.

Free light-shape focusing in extreme-ultraviolet radiation with self-evolutionary photon sieves

Extreme-ultraviolet (EUV) radiation is a promising tool, not only for probing microscopic activities but also for processing nanoscale structures and performing high-resolution imaging. In this study, we demonstrate an innovative method to generate free light-shape focusing with self-evolutionary photon sieves under a single-shot coherent EUV laser; this includes vortex focus shaping, array focusing, and structured-light shaping. The results demonstrate that self-evolutionary photon sieves, consisting of a large number of specific pinholes fabricated on a piece of Si3N4 membrane, are capable of freely regulating an EUV light field, for which high-performance focusing elements are extremely lacking, let alone free light-shape focusing. Our proposed versatile photon sieves are a key breakthrough in focusing technology in the EUV region and pave the way for high-resolution soft X-ray microscopy, spectroscopy in materials science, shorter lithography, and attosecond metrology in next-generation synchrotron radiation and free-electron lasers.

Fabrication of bimetallic Co/Ni composite oxides on Ni-foam as a highly active monolithic membrane catalyst for the reduction of 4-nitrophenol

The development of highly active non-noble metal catalysts is the prerequisite for the practical application of the reduction of 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) by NaBH4. In this work, inexpensive Co/Ni bimetallic composite oxide integral membrane catalysts with different metal-ion molar ratios towards 4-NP reduction were grown on the nickel foam (NF) substrate by a facile oxalate-pyrolysis method. Benefiting from the synergistic effect between Co and Ni elements, special crystalline phase of NiCo2O4 with high electron transfer capacity and uniform nanoflake array structure, the NF-based monolithic membrane catalyst with a Co/Ni molar ratio of 2:1 (Co2Ni1) exhibited the optimal activity for the catalytic reduction of 4-NP. A reduction ratio of 96.71% for 250 mL of 4-NP with an initial concentration of 15 mg/L could be reached within 25 min under the reaction conditions as follows: two pieces of Co2Ni1 catalytic membranes (20 × 40 mm2), 0.015 mol/L NaBH4 and a temperature of 25 °C. The corresponding kinetic reaction rate constant was 0.1410 min−1, which was 2.0 and 15.5 times higher than that of pure Co3O4 and NiO. Moreover, the activation energy, enthalpy and entropy for the reaction were calculated as 17.44 kJ/mol, 14.97 kJ/mol and −210.61 J•mol−1•K−1, respectively. Notably, the reduction rates of 4-NP remained at around 97% during thirteen consecutive catalytic runs, indicating the good reusability of the Co2Ni1 integral membrane catalyst. These results show that NF-based Co/Ni composite oxide membrane is a promising integral catalyst for converting of 4-NP into 4-AP owing to its excellent properties and easy recovery feature.

Advanced PEM Electrolyzer Membrane for Hydrogen Crossover Mitigation

Proton Exchange Membrane (PEM) electrolyzers are a promising technology to produce hydrogen as a clean energy carrier. However, a significant challenge is hydrogen crossover, especially at high pressures (>40 bar) and when utilizing thin (<100 um) membranes. This poses significant safety hazard due to the mixing of H2 with oxygen, especially in the balance of plant due to higher void volumes.Mitigating membrane crossover is therefore critical to the safety of the entire PEM electrolyzer system. Several research groups have demonstrated preliminary works on the H2 crossover mitigated membrane for PEM electrolyzers. Klose et al. [1] implemented a Pt interlayer between one piece of NR212 membrane and a piece of N115 membrane. The work showed significant reduction of H2 crossover in their design compared to the regular PFSA membrane. However, the work only demonstrated the effectiveness of crossover reduction under ambient pressure. Moreover, the spraying method they proposed is not readily scalable. Stahler et al. [2] demonstrated that applying an interlayer between the anode catalyst layer and recombination layer will help to reduce the H2 crossover. However, this work also failed to demonstrate mitigation at high H2 pressure. Additionally, each of these methods used Pt/C in the recombination layer. Carbon, though robust in the fuel cell applications may readily oxidize at the higher electrolyzer potentials. This could have consequences on membrane durability.Preliminary data has demonstrated that our proposed mitigate strategy can significantly reduce the H2 crossover. The MEA with regular NR212 membrane cannot be operated safely under 70 oC under even mild pressure. However, with our addition of the highly efficient recombination layer, the crossover can be dropped to 6% LEL even at 40 bar. This discovery will help to improve the PEM electrolyzer safety dramatically.

Ultra-trace determination of cadmium in water and food samples by a thin-film microextraction using a supported liquid membrane combined with smartphone-based colorimetric detection.

A mixture of n-octanol and dithizone was introduced as an effective and novel extraction agent in a thin-film microextraction technique for the pre-concentration of cadmium ions. The extraction agent was immobilized on small pieces of porous polypropylene flat membrane as a supported liquid membrane. The analyte extraction was performed by immersing the modified film in the sample solution, and via a complex formation between the immobilized dithizone on the film and cadmium ions. After the thin-film microextraction process, the colored cadmium-dithizone complex was directly measured by a smartphone colorimetric analysis. Under optimized conditions, the linear dynamic range, the limit of detection, and the limit of quantification were 0.5-300.0, 0.1, and 0.4μg L-1, respectively. The developed technique was successfully employed to quantify cadmium ions in water and food samples. The high relative recovery values (95.0-103.0%) along with relative standard deviations of less than 2.5% were obtained for the spiked samples.

Lead-imprinted polyvinylidene fluoride membrane for selective removal of lead from contaminated water: material fabrication, filtration application, and mechanism study.

The drinking water has become contaminated with lead in many countries across the world. In this study, a novel lead-imprinted polyvinylidene fluoride (PVDF) membrane was successfully fabricated for selective decontamination of lead from water. First of all, the membrane fabrication process was explored and optimized. The physical and chemical properties were then studied for a better understanding of the features of the membrane. The performance of lead removal by the adsorptive membrane was evaluated by systematic batch adsorption experiments, including pH effect, kinetics, isotherm, selectivity, and regeneration studies. The results indicated that the adsorptive membrane showed a high adsorption capacity of 40.59 mg Pb/g at the optimal pH of 5.5, fast kinetics of 2 h, high selectivity towards lead, and outstanding regeneration performance. The Langmuir equation fitted the isotherm better than the Freundlich equation, while the pseudo-second-order model and pore diffusion model well described the kinetics. The adsorptive membrane showed high selectivity towards lead in the lead/zinc binary solution. In the continuous filtration study, a small piece of adsorptive membrane could treat 3.75 L of lead solution. The XPS studies revealed that the lead uptake was mainly due to the complex reaction between lead and carboxyl and hydroxyl in the membrane.

Determination of the Sterilization Dose of Gamma-Ray Irradiation for Polyvinyl Alcohol-Collagen-Chitosan Composite Membrane as a Material for Periodontal Regenerative Surgery.

Membrane sterility is very necessary considering its function as an implant material. Therefore, this research aims to determine the dose of gamma-ray irradiation for the sterilization of polyvinyl alcohol (PVA)-collagen-chitosan composite membranes used as regenerative surgery materials. A total of 100 pieces of the composite membranes were prepared in a size of 2.0 × 1.5 cm by mixing 7.5% PVA, 3% collagen, and 2% chitosan using the film casting method in three batches. Furthermore, the bioburden test was performed to determine the initial microbial count in the sample by following ISO 11737-1. The results were used to ascertain the dose of gamma-ray irradiation on the sample according to ISO 11137-2. The dose verification test was then performed at the sterility assurance level 10-6. The average result of the bioburden test from three batches was 6.6 colony forming unit; hence, the verification dose was 4.8 kGy. In the verification dose test, since there was only one contaminated sample, the sterility dose test was continued. The sterile gamma-ray irradiation dose for PVA-collagen-chitosan composite membrane was 17.1 kGy.

Lipase-interfacial catalytic systems based on hybrid membranes constructed via electrospinning and gelation

Based on the core appeal of increasing the catalytic interface area, the innovation of structural interface design in the field of lipase catalysis is increasingly demanding. Inspired by wetting and infiltration of fabric, two radically new catalytic systems were developed by electrospinning and gelation. The water swelling (containing lipase) and oil infiltration (containing substrate) of hydrogel fiber-hydrophobic fiber hybrid membranes (hg-HMs) or hydrogel-hydrophobic block fiber hybrid membranes (hg-BHMs) created efficient water-oil interfaces for lipases. The specific activity of lipases inside hg-HMs and hg-BHMs reached 2.56-fold and 2.12-fold separately that in the macroscopic “oil-up/water-down” system, and 1.93-fold and 2.01-fold that in the emulsion catalytic system. The lipases in hg-HMs and hg-BHMs retained high efficiency along time (3.97-fold and 3.54-fold after 3 h of catalysis) with additionally excellent advantages in wide range of temperature and pH, and reusability. Excitingly, with increased pieces of membranes, the assembled hybrid membrane reactors (HMRs) showed a significant increase in catalytic efficiency but basically unchanged specific activity in finite space, which extremely magnified advantage over the control group. This study was a meaningful exploration of micro interfacial lipase catalytic system, which is helpful for further application of liquid-liquid interfacial catalysis in food industry.

„MAGIC“ AMNIOTIC MEMBRANE IN EYE SURGERY

Our goal is to prove that during corneal perforation, when it is larger than 3 mm, we should not rush to perform keratoplasty (cornea transplant). First, we should do our best and fight to the end to preserve a patient's own cornea, in which the amniotic membrane will help us. In 15 patients with corneal perforation, where the size of the perforation exceeded 3-4 mm, surgical treatment was performed and a piece of the amniotic membrane was applied to the cornea. In 14 patients out of 15, their own cornea and moderate or high vision have been preserved. And only 1 patient required keratoplasty.

CRISPR/Cas12a-Enabled Multiplex Biosensing Strategy Via an Affordable and Visual Nylon Membrane Readout.

Most multiplex nucleic acids detection methods require numerous reagents and high-priced instruments. The emerging clustered regularly interspaced short palindromic repeats (CRISPR)/Cas has been regarded as a promising point-of-care (POC) strategy for nucleic acids detection. However, how to achieve CRISPR/Cas multiplex biosensing remains a challenge. Here, an affordable means termed CRISPR-RDB (CRISPR-based reverse dot blot) for multiplex target detection in parallel, which possesses the advantages of high sensitivity and specificity, cost-effectiveness, instrument-free, ease to use, and visualization is reported. CRISPR-RDB integrates the trans-cleavage activity of CRISPR-Cas12a with a commercial RDB technique. It utilizes different Cas12a-crRNA complexes to separately identify multiple targets in one sample and converts targeted information into colorimetric signals on a piece of accessible nylon membrane that attaches corresponding specific-oligonucleotide probes. It has demonstrated that the versatility of CRISPR-RDB by constructing a four-channel system to simultaneously detect influenza A, influenza B, respiratory syncytial virus, and SARS-CoV-2. With a simple modification of crRNAs, the CRISPR-RDB can be modified to detect human papillomavirus, saving two-thirds of the time compared to a commercial PCR-RDB kit. Further, a user-friendly microchip system for convenient use, as well as a smartphone app for signal interpretation, is engineered. CRISPR-RDB represents a desirable option for multiplexed biosensing and on-site diagnosis.

In vitro analysis of factors affecting the continuous hemodiafiltration clearance of teicoplanin.

In the treatment of sepsis, continuous hemodiafiltration (CHDF) and the administration of antibiotics such as teicoplanin (TEIC) are frequently performed in parallel. We aimed to clarify the factors influencing the CHDF clearance (CLCHDF ) of TEIC using a polymethylmethacrylate (PMMA) membrane or a polyacrylonitrile and sodium methallyl sulfonate copolymer membrane coated with polyethylenimine (AN69ST). We also investigated whether the adsorption of TEIC onto the hemofilters inhibits the adsorption of interleukin (IL)-6 onto the membranes. TEIC, human serum albumin (HSA), and IL-6 were incubated with pieces of hemofilter membranes and adsorption rates were calculated. The CLCHDF , diafiltration rate, and adsorption rate of TEIC were calculated using an in vitro CHDF circuit model. The adsorption rates of TEIC onto the pieces of PMMA and AN69ST membranes ranged from 15.0% to 100% and from -10% to 5%, respectively. The adsorption rate of IL-6 was similar with or without TEIC. The CLCHDF and adsorption rate of TEIC under PMMA-CHDF depended on HSA, but not on effluent flow rate (Qe). The CLCHDF under AN69ST-CHDF depended on HSA and Qe. The observed CLCHDF under AN69ST-CHDF was similar to the predicted value (the product of Qe and the plasma unbound fraction). The observed CLCHDF under PMMA-CHDF was 2.0-7.8 times greater than the predicted value. Adsorption mainly contributes to the CLCHDF of TEIC using PMMA membranes, whereas diafiltration mainly contributes to the CLCHDF of TEIC using AN69ST membranes. TEIC adsorption might not affect the adsorption of IL-6 onto PMMA membrane.

Differentiation of Fibroblasts Into Myofibroblasts in the Arachnoid Membrane of Moyamoya Disease.

Moyamoya disease (MMD) is a very specific disorder in terms of spontaneous development of extracranial-to-intracranial collateral circulation through the dura mater, but the underlying mechanisms are unclear. This study aimed to investigate the role of the arachnoid membrane in this unique angiogenesis in MMD. A piece of arachnoid membrane and 1- to 2-mL cerebrospinal fluid were simultaneously harvested during surgery from 26 patients with MMD. The specimens were also collected during surgery as the controls from 6 patients with atherosclerotic carotid artery diseases. The arachnoid membrane was subjected to immunohistochemistry and the cerebrospinal fluid was used to measure the concentration of cytokines using ELISA. The number of cells positive for PDGFR (platelet-derived growth factor receptor) α was significantly higher in MMD than in the controls (5.4±3.1 versus 2.3±2.1 cells/field; P=0.02). The results were same in PDGFRβ-positive cells (10.1±4.6 versus 4.8±2.8; P=0.01) and α-SMA (alpha-smooth muscle actin)-positive cells (8.8±3.1 versus 2.0±2.5; P<0.01). On multicolor immunofluorescence, 80.5±15.6% of cells positive for PDGFRα in MMD also expressed α-SMA, being significantly higher than 14.6±7.2% in the controls (P<0.01). The density of collagen in the arachnoid membrane was significantly higher in MMD than in the controls (60.3±15.0% versus 40.1±15.3%; P<0.01). In MMD, advanced disease stage was significantly associated with a larger number of α-SMA-positive cells in the arachnoid membrane (P=0.04). On ELISA, the cerebrospinal fluid concentrations of bFGF (basic fibroblast growth factor), HGF (hepatocyte growth factor), and TGF (transforming growth factor)-β1 were significantly higher in MMD than in the controls. Based on these findings, MMD may elevate the concentrations of angiogenic factors in the cerebrospinal fluid and then promote the proliferation of fibroblasts in the arachnoid membrane and their differentiation into myofibroblasts, which may, in turn, enhance the production of collagen essential for spontaneous collateral formation across the arachnoid membrane.

Protected Laparoscopic Large Ovarian Cyst Aspiration: A 5-Step Alternative to Laparotomy

In this video, we describe a 5-step surgical technique that allows us to safely incise and aspirate the content of large ovarian cysts through a single-port laparoscopic incision. This allows performing laparoscopic oophorectomies instead of large xipho-pubic laparotomies. A stepwise demonstration of the technique with narrated video footage. Ovarian masses, especially cysts, are common gynecologic conditions [1]. However, depending on their size, large adnexal cysts are usually managed with transverse or midline laparotomies [2]. This is to prevent cyst ruptures and abdominal contamination and ensure oncological safety of the procedure [3-5]. Different leak-proof aspiration techniques have been described in the literature allowing for safe large cyst aspiration and adnexectomy through a mini-laparotomy incision or via laparoscopy [2,3,6-10]. We describe a 5-step surgical technique allowing for closed aspiration of ovarian intracystic fluid and adnexectomy while respecting oncological safety. Step 1: Perform diagnostic laparoscopy to rule out peritoneal carcinomatosis contraindicating this procedure and then after cyst exposition, thoroughly dry the cyst wall. Step 1 Bis: Cut the cuff of a sterile glove to prepare a square piece of membrane. Step 2: Place a protective gauze and then apply the surgical glue to the ovarian cyst wall followed by the glove/membrane application. Perform a purse suture through the glove/membrane and the ovarian wall superficially to ensure further adhesion and prevent ovarian fluid spillage. Step 3: Incise the ovarian wall, introduce the aspiration cannula and tighten the purse suture to aspirate the cystic fluid. Step 4: After aspiration is complete, tighten the suture and close the glove to guarantee a closed space and prevent abdominal contamination. Step 5: Perform laparoscopic oophorectomy or cystectomy. Safely remove the specimen in an endoscopic retrieval bag through the trocar incision. This technique allows safe laparoscopic large ovarian cysts resections while respecting oncologic safety and preventing intra-abdominal spillage and contamination.

Industrial-scale fabrication of mordenite membranes by dual heating method for production of ethyl acetate in an industrial VP-esterification plant

High-performance industrial-scale mordenite membranes were successfully prepared on 100-cm-long tubular macroporous mullite supports using a large autoclave containing 50 pieces (membrane area: 1.88 m 2 ) by a dual heating method. The effects of different heating methods on temperature and concentration distribution in the industrial autoclave were discussed in detail. Mordenite membranes prepared using a dual heating method by eliminating the temperature and concentration gradients showed excellent reproducibility, with an average flux of more than 2 kg m −2 h −1 for separation of a 90 wt% HAc/H 2 O mixture at 90 °C. The qualification rate of industrial-scale membranes produced in a single autoclave was more than 90%. Additionally, 345 pieces of industrial-scale mordenite membranes with a total membrane area of ca. 12.6 m 2 were assembled into 3 membrane modules in an industrial vapor permeation (VP) plant to intensify esterification of acetic acid and ethanol by rapid dehydration. The industrial VP-esterification plant produced 99.5 wt% ethyl acetate with a product flow rate of about 140 kg h −1 and the annual output exceeded 1000 tons. Importantly, the industrial plant showed an excellent stability for operating over 100 d, illustrating that the industrial-scale mordenite membranes had a high stability in industrial application of esterification of acetic acid and ethanol to produce ethyl acetate. • 50 pieces of 100-cm-long mordenite membranes were prepared in a single autoclave. • Reproducible industrial-scale membranes were synthesized by a dual heating method. • Ethyl acetate was produced by coupling of esterification with VP in an industrial plant. • Industrial VP-esterification plant showed a good stability for operating over 100 d.

A multifunctional and low-energy electrochemical membrane system for chemical-free regulation of solution pH

A proper pH environment is essential for a wide variety of industries and applications especially related to water treatment. Current methods for pH adjustment including addition of acid/base and electrochemical processes demonstrate disadvantages associated with environment and energy. Here, we designed a multifunctional electrochemical membrane system (EMS) with one piece of filtration membrane inserted into an electrochemical cell. When electrical field was applied, OH− and H+ ions were produced from reduction and oxidation reactions at cathode and anode, respectively. The membrane posed a resistance for the transport of OH− and H+ ions and prevented their mixing in the cell. The EMS can be also operated in a filtration mode, which could simultaneously regulate permeate and feed pH and accomplish water filtration. In both non-filtration and filtration modes, EMS could achieve effective control of solution pH over a wide range by exerting different voltages without dosing any chemicals. Under the voltage of 1.2 V, the solution pH could reach and be maintained at 10.7 and 3.3 in cathodic and anodic channels, respectively. Furthermore, it was experimentally demonstrated that the EMS only consumed extremely low energy. This, together with membrane filtration in an integrated manner, highlights the huge potential of the EMS for applications in various water industries.