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To fabricate hydrophilic and anti-fouling PVDF ultrafiltration membrane, a kind of tailor-made symmetrical amphiphilic triblock copolymer, polyacryloylmorpholine- b -poly (methyl methacrylate)- b -polyacryloylmorpholine (PACMO- b -PMMA- b -PACMO, termed as PAMA), was prepared via RAFT polymerization and employed as an in situ surface segregation modifier. FTIR, 1H NMR, and GPC were used to verify the well-defined chemical structure of PAMA. The hydrophilic PACMO segments of PAMA were enriched on the surface of membrane skin and interior pores as confirmed by ATR-FTIR, XPS, EDX, and water contact angle tests, endowing the blend membranes with outstanding hydrophilicity. The different cross-sectional and surface morphologies of the PVDF/PAMA blend membranes indicated that the introduction of PAMA modifiers could manipulate membrane structure due to their strong pore-forming ability. Compared with the pure PVDF membrane, PVDF/PAMA blend membranes showed higher permeability for water (28.1 times higher), excellent rejection for bovine serum albumin (up to 98.3%), and enhanced fouling resistance with a higher flux recovery ratio (up to 98.1%). Therefore, the approach of in situ surface segregation employed the RAFT mediated well-defined amphiphilic PAMA triblock copolymer modifiers for the preparation of anti-fouling PVDF membranes showed a great potential in water purification. [ABSTRACT FROM AUTHOR]

Abstract: A fluorinated monomer of 2-(2,2,2-trifluoroethoxy)ethyl methacrylate (FEMA) was prepared by a “one pot” process and then a novel fluorinated methacrylate polymer, poly[2-(2,2,2-trifluoroethoxy)ethyl methacrylate] (PFEMA), was successfully synthesized via miniemulsion polymerization using cetyltrimethyl ammonium bromide (CTAB) as emulsifier, hexadecane (HD) as co-stabilizer and 2,2′-azobisisobutyronitrile (AIBN) as initiator. The chemical structure of PFEMA was characterized by FT-IR, 1H NMR and 19F NMR. GPC results show that the number average molecular weight (M n) of PFEMA was as high as 8.5×105 g/mol and the polydispersity index (PDI) was only 1.3. SEM and DLS characterizations showed that the morphology of PFEMA latex was uniform spheres with the diameter of about 110–125nm. It was also found that PFEMA has high thermo-stability (T d >200°C), low glass transition temperature (T g =13.0°C), and nice hydrophobicity (θ water =99.9°). Comparison studies on PFEMA and poly(2,2,2-trifluoroethyl methacrylate) show that an introduced functional group (–CH2CH2O–) has a significant effect on lowering T g and improving hydrolysis resistance without impairing surface properties. [Copyright &y& Elsevier]

• Quaternary ammonium and zwitterion dual-functionalized PDB- b -PSB brushes on MF membrane surface were fabricated. • The membrane pore size was not significantly changed by the coating. • Surface hydrophilicity of M/PDB- b -PSB membrane enhanced obviously. • M/PDB- b -PSB membrane with passive anti-adhesive and upper active biocidal properties. • Modification strategy for ant-biofouling membrane was facile and promising. In order to improve permeability and biofouling resistance of microfiltration (MF) membranes, quaternary ammonium and zwitterion dual-functionalized diblock polyelectrolyte copolymers, poly(dimethylaminoethyl methacrylate-butylammonium bromide)- b -poly(sulfobetaine methacrylate) (PDB- b -PSB) prepared via RAFT polymerization, were immobilized on commercial poly(vinylidene fluoride) (PVDF) MF membrane surface via using a versatile and facile mussel-inspired method to fabricate hierarchical copolymer brushes. Hierarchical PDB- b -PSB brushes contained bottom passive anti-adhesive zwitterionic PSB layer and upper active biocidal quaternary ammonium PDB layer. The surface chemical composition and morphology characterizations of pure and modified membranes demonstrated that PDB- b -PSB copolymers were successfully grafted to the dopamine-modified membrane surface via thiol mediated Michael addition reaction, which did not significantly change the membrane pore structure. However, the initial contact angle of PDB- b -PSB modified membrane (M/PDB- b -PSB) was changed from 128° for pure membrane (M/pure) to 43.2° and became 0° within 10 s, indicating the enhanced hydrophilicity. More importantly, the M/PDB- b -PSB membrane exhibited active biocidal effects against E. coli and S. aureus with inhibition rates over 98% and the E. coli and S. aureus suspension fluxes of M/PDB- b -PSB membranes were 1.61 times and 1.35 times higher than those of M/pure membranes. The M/PDB- b -PSB membrane had excellent anti-biofouling property with a better water flux recovery rate of 72%, which was 30% higher than that of the M/pure membrane. Moreover, PDB- b -PSB brushes showed a good immobilization stability. Therefore, the approach of poly(dopamine)-assisted fabrication of anti-biofouling MF membranes with quaternary ammonium and zwitterion dual-functionalized diblock copolymers had a prospect application in membrane-based separation technology and water purification. [ABSTRACT FROM AUTHOR]

• Three kinds of comb-shaped amphiphilic PEME triblock copolymers were synthesized. • Effects of PEME with different hydrophilic block length on membrane structure-property relationship. • M-2 membrane exhibited high BSA solution flux (150 L·m−2·h−1) and excellent rejection (99.99%). • M-2 membrane overcame the permeability-selectivity trade-off for BSA solution separation. In order to reduce membrane fouling and fabricate highly selective membranes with high water permeability, three kinds of comb-shaped amphiphilic triblock copolymers, poly[poly(ethylene glycol) methacrylate]- b -poly(methyl methacrylate)- b -poly[poly(ethylene glycol) methacrylate] (PPEGMA- b -PMMA- b -PPEGMA, named as PEME), were synthesized via RAFT polymerization and used as modifiers to prepare poly(vinylidene fluoride) (PVDF) blend membranes by the non-solvent induced phase separation (NIPS) method. The effects of PEME with different hydrophilic PPEGMA length on the surface chemical structure, morphology, permeability and antifouling properties of the blend membranes were investigated detailedly. The results from ATR-FTIR and XPS tests confirmed that hydrophilic PPEGMA segments in PEME were enriched on the membrane surface due to PEME induced surface segregation. With the increase of the hydrophilic chain length in PEME, the mean pore size, porosity and roughness of the blend membrane increased gradually, indicating the modifier had the ability to adjust the membrane pore structure. Compared with pure membrane, the hydrophilicity of blend membranes was enhanced and the protein adsorption of representative bovine serum albumin (BSA) decreased obviously. After three cycles of the water-BSA-water, the M-2 blend membrane exhibited high BSA solution flux (150 L·m−2·h−1), excellent rejection (up to 99.99%) and satisfactory antifouling performance. In addition, compared with the recently published PVDF blend ultrafiltration membranes prepared by NIPS method, the M-2 membrane with surface small pore size, high flux, high selectivity and low fouling properties overcame the permeability-selectivity trade-off for BSA solution separation and showed a good application prospect for efficiently protein separation. [ABSTRACT FROM AUTHOR]

Superhydrophilic and underwater superoleophobic membranes have recently attracted significant interest as materials for effective oil-water emulsion separation. In this work, a superwetting membrane with a spider web structured gel layer was designed for efficient oil-water separation. Biomaterial, carboxymethyl cellulose (CMC), was used as the raw material, a spider web structured gel layer was constructed on the PVDF membrane surface by heat-treatment and chemical cross-linking. The hydrophilic gel layer imparted excellent superhydrophilic and underwater superoleophobic properties to the membrane, while the special spider web structure improved the membrane mechanical stability. The fabricated membrane exhibited superhydrophilicity and underwater superoleophobicity. Among different CMC concentration-modified membranes, the M-0.5 membrane containing 0.5 wt% CMC exhibited a flux of 612 L·m−2 h−1 during dichloromethane oil-water emulsion separation, which was 4.2-fold higher than that of the pristine PVDF membrane, while the membrane showed efficient oil-water separation capacity. Additionally, the water flux recovery reached as high as 93.3 %, and oil rejection attained 99.1 %. Meanwhile, the spiderweb-structured gel layer on the membrane surface displayed good mechanical stability. In summary, this novel membrane-modification method, inspired by the spider web structure, was simple, cost effective and environmentally friendly, thereby making it promising for future preparation of highly efficient oil-water emulsion separation membranes. [Display omitted] • The natural biomaterial CMC was used as a gel material to modify the membrane. • Bionic-inspired construction of spider web-like gel layer on membranes. • The ultrathin gel layer on the membrane surface did not block the membrane pores. • The membrane exhibited separation performance and anti-fouling properties for oil-water emulsions. • The special spider web structure gel layer enhanced the membrane mechanical properties. [ABSTRACT FROM AUTHOR]

Traditional thin film composite polyamide nanofiltration (NF) membranes are difficult to simultaneously achieve high rejection for salts that are divalent anionic and cationic, and their separation selectivity for mono-/di-valent salt separation is usually poor. Herein, novel polyesteramide NF membranes were developed by interfacial polymerization on modified poly(vinylidene fluoride) (PVDF) substrates containing tannic acid (TA) self-assembled coating (TC@PVDF). TC@PVDF substrates were firstly fabricated via non-solvent induced phase separation technology using amphiphilic hyperbranched poly(methyl methacrylate- co -N-methylacrylamide) (HPMH) copolymers as in situ modifiers and TA aqueous solution as coagulation bath. The self-assembly behavior between TA and HPMH results in the increase of substrate surface hydrophilicity, electronegativity and pore size, which would facilitate the storage and uniform distribution of aqueous monomer piperazine on the substrate surface. For these reasons, TA coating interlayered NF (TCi-NF) membrane exhibits a thick polyesteramide layer with crisscrossing ridge surface morphology, a low molecular weight and a small pore size. The TCi-NF membrane not only demonstrates high rejection toward Na 2 SO 4 (99.3 %) and MgCl 2 (95.7 %), but also displays exceptional separation selectivity for both mono-/di-valent anions [α(Cl−/SO 4 2−) = 49] and mono-/di-valent cations [α(Na+/Mg2+) = 52]. Since the surface charge property of TCi-NF membrane is close to weak negativity, electrostatic effect between charged ions and membrane surface would be weakened, so the separation mechanism mainly depends on the size exclusion effect. Specifically, the TCi-NF membrane displays stable long-term separation performance and high salt concentration resistance. Therefore, this research provides a new preparation strategy for improving the precise desalination performance of thin film composite NF membranes. [Display omitted] • Tannic acid (TA) aqueous solution as coagulation bath adjusts structure of substrates by surface self-assembly. • TA coating interlayer (TCi) plays multiple roles in interfacial polymerization process. • Weakly negative TCi-NF membrane with low MWCO and small pore size. • Outstanding separation selectivity for both Cl−/SO 4 2− and Na+/Mg2+. • Excellent long-term stability and high salt concentration resistance. [ABSTRACT FROM AUTHOR]

To explore breast cancer (BC) patients' participation in breast reconstruction (BR) decision-making and specific decisional needs, especially the manifestations and causes of decisional conflicts, in China. A mixed-methods study was conducted using triangulation of data from interviews and a questionnaire survey with health care professionals (HCPs) and BC patients with BR decision-making experience at 5 Beijing centers. The Ottawa Decision Support Framework guided (ODSF) the qualitative and quantitative data analyses. A total of 82.53% of Chinese BC patients would consider BR. Seven themes captured patients' BR decisional needs per the ODSF: inadequate support/resources (100%, 58.82%) and knowledge (75%, 52.94%) were most frequently cited. Health beliefs (unclear values) reflected Chinese characteristics. Patients had inadequate knowledge (M=19.99/50, SD=8.67) but positive BR attitudes (M=59.48/95, SD=10.45). BR decisions for Chinese BC patients are complex and often accompanied by decisional conflicts. Inadequate knowledge and inadequate support and resources contribute to these conflicts, emphasizing the need for culturally tailored information and support to promote SDM. HCPs need specialized training in SDM to guide patients in decision-making. It is essential to provide relevant resources and support that are culturally and clinically appropriate for Chinese patients. • Chinese breast cancer patients face decisional conflicts and lack knowledge/support for breast reconstruction (BR). • Cultural characteristics and health beliefs influence the decision-making process for BR among Chinese patients. • Tailored information and support are vital to promote shared decision-making (SDM) and meet individual patient needs. [ABSTRACT FROM AUTHOR]

Inspired by trimethylamine N -oxide (TMAO) secreted by saltwater fish, a novel ultra-low fouling material of N -oxide zwitterion (PTMAO) was introduced to the membrane surface via a dual-biomimetic strategy for efficient oil–water separation at near "zero pressure". [Display omitted] • Synthesized a novel N -oxide zwitterionic (PTMAO) material with ultra-low fouling. • Direct linkage of positive and negative charges (N+-O−) in PTMAO provided excellent hydrophilicity. • Bioinspired PTMAO was introduced into the membrane surface by biomimetic co-deposition chemistry. • PTMAO was introduced to endow the membrane with super-hydrophilic and oil repellent properties. • Membrane prepared by dual-biomimetic strategy showed efficient oil–water separation property. Superwetting membranes have good prospective for treatment of oil-containing wastewaters. However, development of simple and environment-friendly membranes with efficient oil–water separation performance remains a great challenge that needs to be addressed urgently. In this study, inspired by the secretion of trimethylamine- N -oxide (TMAO) by saltwater fish, we report a novel N ‑oxide zwitterionic polymer (PTMAO) with ultralow fouling property possessing directly linked opposite charges in their molecules and superior hydrophilicity, as compared to conventional zwitterionic ones. Using biomimetic co-deposition technique of dopamine (DA) and PTMAO, a zwitterionic polymer network was formed via self-polymerization of DA and followed by hydrogen bonding and cation-π effects between the oxidatively generated polydopamine (PD) and PTMAO. As expected, the fabricated membrane exhibited excellent superhydrophilicity and underwater superoleophobicity. The M–PD/PT/2:2 membrane achieved high efficiency of oil–water separation performance under ultra-low-pressure conditions, with an oil–water emulsion flux of 1121.1 L/m2 h, a recovery rate of 93.1%, and oil rejection as high as 99.2% in the cyclic oil–water emulsion separation process. Meanwhile, the M–PD/PT/2:2 membrane showed excellent stability. Therefore, this work provides a new idea for the preparation of superwetting membranes using dual-biomimetic techniques for effective separation of oil–water emulsion. [ABSTRACT FROM AUTHOR]

Resveratrol (RES) is a plant extract with excellent antioxidant, biocompatibility, anti-inflammatory and inhibition of platelet aggregation. RES-modified polysulfone (PSF) hemodialysis membranes have been fabricated using an immersion phase transformation method. The antioxidant properties of the blend membranes were evaluated in terms of their 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonate) (ABTS+), reactive oxygen species (ROS) free radicals scavenging, total antioxidant capacity (T-AOC) of serum and lipid peroxidation inhibition. The observed results of decreasing DPPH and ABTS+ levels, scavenging ROS, significant inhibition of lipid peroxidation and improving the T-AOC of serum all contribute to the recovery of oxidative balance and the use of RES as an antioxidant modifier. The antioxidant stability of PSF/RES blend membranes was also studied. Moreover, the results of blood compatibility experiments showed that the addition of RES improved the blood compatibility of PSF membrane, inhibited the adhesion of red blood cells and platelets; inhibited complement activation; and reduced the blood cells deformation rate. The dialysis simulation experiment indicated that PSF/RES membrane (M-3) can clear 90.33% urea, 89.50% creatinine, 74.60% lysozyme and retention 90.47% BSA. All these results showed the new PSF/RES blend membranes have potential to be used in the field of hemodialysis to improve oxidative stress status in patients. [Display omitted] • Resveratrol, a natural plant-based antioxidant, was introduced into polysulfone dialysis membrane. • The modified membranes had strong oxidation resistance that could scavenge free radicals and inhibit lipid peroxidation. • The antioxidant activity of modified membranes was extraordinary stable for 60 d preservation. • The modified membranes had excellent blood compatibility, cytocompatibility and dialysis performance. [ABSTRACT FROM AUTHOR]

Hydrophilic polymers with low affinity for foulants were broadly utilized as functional membrane surface modifiers to mitigate fouling owing to superior hydration capability. Herein, novel hydrophilic hyperbranched poly(N-acryoyl morpholine) (HPA) synthesized through one-step RAFT polymerization was immobilized onto commercial PVDF microfiltration membrane surface using biomimetic adhesion polydopamine as an intermediate reaction platform. The surface composition and morphology of HPA decorated membranes (M-PD/HPA) were examined, demonstrating that the nano-sized HPA was facilely anchored on the membrane surface without obviously changing membrane pore size and distribution. In comparision with hydrophobic pure membrane (M-PVDF), hydrophilic and underwater superoleophobic M-PD/HPA exhibited excellent multiple defense capability toward oil, protein and bacteria due to the presence of a steric repulsive barrier of hydrated HPA layer. For model hexane-in-water emulsion separation at 0.02 MPa, permeation flux of M-PD/HPA up to 149.8 L m−2 h−1 was improved by three times and the rejection was up to 99.5%. Importantly, for the separation of complex artificial oily wastewater, relevant flux reduction of M-PD/HPA was decreased from 60.9% of M-PVDF to 36.8% and flux recovery ratio of M-PD/HPA was increased from 34.8% to 82.6%. Therefore, M-PD/HPA has a promising prospect for emulsified oil separation and water purification. Unlabelled Image • Novel hydrophilic hyperbranched Poly(N-acryoyl morpholine) (HPA) synthesized by one-pot RAFT. • HPA was immobilized on membrane surface via biomimetic adhesive chemistry. • HPA coating simultaneously enhanced surface hydrophilicity and roughness. • HPA modified membrane with enhanced separation and antifouling performance. [ABSTRACT FROM AUTHOR]

• Schizophrenia exhibited reduced theta-band power and graph measures. • Clozapine treatment can significantly reduce task-related theta-band power. • Schizophrenia exhibited weaker frontal-occipital and temporal-occipital connections. • A classification accuracy of 84.48% was obtained between schizophrenia and healthy controls. Previous studies have reported that schizophrenia (SZ) patients showed selective reinforcement learning deficits and abnormal feedback-related event-related potential (ERP) components. However, how the brain networks and their topological properties evolve over time during transient feedback-related cognition processing in SZ patients has not been investigated so far. In this paper, using publicly available feedback-related ERP data which were recorded from SZ patients and healthy controls (HC) when they performed a reinforcement learning task, we carried out an event-related network analysis where topology of brain functional networks was characterized with some graph measures including clustering coefficient (C), global efficiency (E global) and local efficiency (E local) on a millisecond timescale. Our results showed that the brain functional networks displayed rapid rearrangements of topological properties during transient feedback-related cognition process for both two groups. More importantly, we found that SZ patients exhibited significantly reduced theta-band (time window of 170–350 ms after stimuli onset) brain functional connectivity strength, E global , E local and C in response to negative feedback stimuli compared to HC group. The network based statistic (NBS) analysis detected one significantly decreased theta-band subnetwork in SZ patients mainly involving in frontal-occipital and temporal-occipital connections compared to HC group. In addition, clozapine treatment seemed to greatly reduce theta-band power and topological measures of brain networks in SZ patients. Finally, the theta-band power, graph measures and functional connectivity were extracted to train a support vector machine classifier for classification of HC from SZ, or Cloz + SZ or Cloz- SZ, and a relatively good classification accuracy of 84.48%, 89.47% and 78.26% was obtained, respectively. The above results suggested a less optimal organization of theta-band brain network in SZ patients, and studying the topological parameters of brain networks evolve over time during transient feedback-related processing could be useful for understanding the pathophysiologic mechanisms underlying reinforcement learning deficits in SZ patients. [ABSTRACT FROM AUTHOR]