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The present work details the development of carbon fiber-reinforced epoxy membranes with excellent rejection of small-molecule dyes. It is a proof-of-concept for a more sustainable membrane design incorporating carbon fibers, and their recycling and reuse. 4,4-methylenebis(cyclohexylamine) (MBCHA) polymerized with either bisphenol-A-diglycidyl ether (BADGE) or tetraphenolethane tetraglycidylether (EPON Resin 1031) in polyethylene glycol (PEG) were used to make monolithic membranes reinforced by nonwoven carbon fibers. Membrane pore sizes were tuned by adjusting the molecular weight of the PEG used in the initial polymerization. Membranes made of BADGE-MBCHA showed rejection of Rose Bengal approaching 100%, while tuning the pore sizes substantially increased the rejection of Methylene Blue from ~65% to nearly 100%. The membrane with the best permselectivity was made of EPON-MBCHA polymerized in PEG 300. It has an average DI flux of 4.48 LMH/bar and an average rejection of 99.6% and 99.8% for Rose Bengal and Methylene Blue dyes, respectively. Degradation in 1.1 M sodium hypochlorite enabled the retrieval of the carbon fiber from the epoxy matrix, suggesting that the monolithic membranes could be recycled to retrieve high-value products rather than downcycled for incineration or used as a lower selectivity membrane. The mechanism for epoxy degradation is hypothesized to be part chemical and part physical due to intense swelling stress leading to erosion that leaves behind undamaged carbon fibers. The retrieved fibers were successfully used to make another membrane exhibiting similar performance to those made with pristine fibers.

Objective: This study aimed to compare the alveolar sealing performance between free gingival graft (FGG) and porcine collagen membrane (MS) and qualitatively assess patient-centered outcomes via a visual analog scale. Method and materials: Eighteen patients were randomly divided into control (FGG) and test (MS) groups. After extraction, all the alveoli were filled with bovine bone grafts (small granules) and sealed. Follow-up was during the immediate postoperative period and after 3, 7, 15, 30, 60, 90, and 120 days. After 180 days, before implant placement, tissue samples were obtained for histologic analysis. The epithelial tissues were morphometrically measured for each sample. Qualitative information on the patient's perception of the treatment was collected after 7 days. Results: A faster healing was observed for the MS group. After 60 days, all the sites from the MS were partially healed, in contrast with only five from the FGG. The histologic results after 120 days showed for the FGG group a predominant acute inflammatory process, whereas chronic processes were observed for the MSgroup. The mean epithelial heights found for the FGG and MS were 535.69 pm and 495.33 pm, respectively (P = .54). The intragroup analysis showed significant variance among the data (P<.001) for both groups. The qualitative result showed statistically more significative comfort for the MS group (P < .05). Conclusion: Within the limitations of the study, both techniques effectively promote alveolar sealing. However, the visual analog scale result was superior and more signiffcant for the MS group, with faster wound healing and lower discomfort. [ABSTRACT FROM AUTHOR]

An emerging cellular engineering method creates synthetic polymer matrices inside cells. By contrast with classical genetic, enzymatic, or radioactive techniques, this materials-based approach introduces non-natural polymers inside cells, thus modifying cellular states and functionalities. Here, we cover various materials and chemistries that have been exploited to create intracellular polymer matrices. In addition, we discuss emergent cellular properties due to the intracellular polymerization, including nonreplicating but active metabolism, maintenance of membrane integrity, and resistance to environmental stressors. We also discuss past work and future opportunities for developing and applying synthetic cells that contain intracellular polymers. The materials-based approach will usher in new applications of synthetic cells for broad biotechnological applications.

Abstract: The aim of this study is to enable the hydrogen economy and decarbonize various sectors in our environment that requires less expensive and more durable water electrolyzers, which can meet the Hydrogen-Shot target. The key is to improve the ionomer interfaces in low-temperature water electrolyzers as rapidly as possible, but to do so, it requires a systematic and holistic campaign combining both experiments and theory. In this perspective, we discuss the issues of electrolyzers and needs for translational science. We then present the approach that the Energy EarthShot Research Center: Center for Ionomer-based Water Electrolysis is taking in hopes of inspiring the community with this approach that can be leveraged to multiple problems and technologies. Graphical abstract: (Figure presented.) Highlights: One way to achieve the Hydrogen-Shot goal of low-cost, clean hydrogen, is advancing research and development on the interfaces of water electrolyzers for both performance and lifetime. The Center for Ionomer-based Water Electrolysis is exploring new techniques and strategies to not only interrogate interfacial phenomena in water electrolyzers to increase efficiency and durability, but also a new paradigm related to synergistic, cojoined experimental and theoretical research. Discussion: Catalyst\ionomer interfaces are complex and not fully understood, but through investigating different interfaces and utilizing digital and physical twins, we can elucidate key mechanisms and understanding. Understanding the dynamic double layer in electrochemical systems that use solid electrolytes is crucial to identifying and mitigating the controlling phenomena to enable increased performance and durability at the technology level. Studying the time and length scales of interfacial changes can be a powerful tool to understand reaction mechanisms and changes in the electrolyzer performance and durability.

Nafion, a perfluorosulfonic acid ionomer, has been well-studied for decades due to its key role as an ion-conductive membrane in electrochemical energy conversion and storage applications. When hydrated, this membrane phase separates into a complex hierarchical nanostructure with hydrophilic domains that facilitate ion transport. Hard X-ray scattering has been a powerful technique in understanding Nafion due to its capabilities in capturing the ionomer’s nanophase separated structure, which gives rise to contrast between polymer and water domains. More recently, resonant X-ray scattering, which tunes to elemental absorption edges to provide specificity on constituent elements, has been explored to highlight key interactions related to the sulfonic acid groups within its structure. Here, we study the Nafion nanostructure by combining hard X-ray scattering and tender resonant X-ray scattering (TReXS) at the sulfur K-edge to reveal a mesoscopic feature corresponding to a correlation length of approximately 40 nm that has been challenging to resolve with hard X-ray studies. Additionally, we study the effect of the dispersion solvent composition that plays a key role in the formation of this mesoscale feature. Notably, TReXS can attain high contrast to decipher this mesoscale morphology even for dry polymer membranes under a vacuum, which typically have reduced contrast for hard X-rays. We find that the correlation length of this mesoscale feature decreases with increasing water fraction in the dispersion, which is the opposite trend exhibited by the smaller intercrystalline feature in the same membranes. This study showcases the utility of TReXS to uncover multiscale morphological details in functional polymers that are not always revealed by other methods like hard X-ray scattering. We illustrate this with Nafion, which is a relevant ion-conducting polymer for electrochemical technologies.

Flexible zeolite membranes are promising for scalable and adaptable separation of critical gases such as helium; however, the synthesis of such membranes remains a significant challenge. In this study, we report the successful fabrication of crack‐free ZSM‐5 zeolite membranes on polytetrafluoroethylene (PTFE) supports using a seeded growth method. PTFE‐supported membranes exhibit unprecedented helium permeance of over 6.7×10−7 mol m−2 s−1 Pa−1 and high He/N2 and He/CH4 separation factors of 17 and 83 respectively, surpassing current state‐of‐the‐art membranes. These flexible membranes maintain excellent separation performance even after bending and stretching. Furthermore, large‐scale membranes demonstrate stable helium separation from multicomponent gas mixtures, showcasing their significant potential for practical helium extraction from natural gas. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) are considered promising candidates for large‐scale energy storage due to their high safety, low cost, and environmental friendliness. As a core component, separator plays a unique yet oftentimes overlooked role in providing electrochemical stability in AZIBs. This concept focuses on the exquisite structure‐property relationship of separators, highlighting three forms of these components and their structural design requirements, i. e., traditional membranes, solid‐state electrolytes, and electrode coatings. The mechanism by which separators influence the zinc anode and the cathode is discussed. The article also identifies the challenges and potential future directions for functional separators in the development of high‐performance AZIBs. [ABSTRACT FROM AUTHOR]

Over the past few decades, chemical vapor deposition (CVD) of [2.2]paracyclophanes has captured significant attention as an emergent technology, producing conformal, chemically pure, and pinhole‐free coatings for biomedical and industrial applications. Compelling examples range from functional CVD polymers to tailored nanostructures. In this work, the unique functional properties of polymers derived from [2.2]paracyclophanes are connected with emergent applications. Special attention is given to the function‐property relationships in the areas of electronic materials, biomaterials, and separation materials. A particular focus is to highlight the versatility of CVD polymerization to process these polymers. [ABSTRACT FROM AUTHOR]

The persistence of defects in polycrystalline membranes poses a substantial obstacle to reaching the theoretical molecular sieving separation and scaling up production. The low membrane selectivity in most reported literature is largely due to the unavoidable non‐selective defects during synthesis, leading to a mismatch between the well‐defined pore structure of polycrystalline molecular sieve materials. This paper presents a novel approach for minimizing non‐selective defects in metal–organic framework (MOF) membranes by a constricted crystal growth strategy in a confined environment. The in situ ZIF formation using the densely packed seeding array between the substrate and the pre‐grown top ZIF layer yields a confined membrane interlayer, which is highly uniform with a tightly packed crystalline structure. Unlike uncontrolled crystal growth, we purposely regulate the interlayer membrane growth in the direction parallel to the substrate. A notable 99 % decrease in defects in the confined interlayer was achieved compared to the random‐grown top layer, leading to a ~353 % increment in H2/N2 selectivity over the non‐confined reference MOF membrane. The performance of this new membrane sits in the optimal range above the Robeson upper bound. The membrane boasts a balanced high H2 permeability (>5000 Barrer) and selectivity (>50), significantly surpassing peer ZIF membranes. [ABSTRACT FROM AUTHOR]

Refractance window drying is a technique that has great potential to dry commodities, with better quality at an affordable cost. However, there is still a lack of awareness regarding its use and implementation in academic curricula as well as in industry. This study aims to design and develop a low-cost and effective Internet of Things (IoT) enabled Infrared (IR) assisted refractance window dryer. The effect of different flexible materials used as membranes with the same thickness was also investigated. Then, experiments were conducted on papaya pulp to study the performance of the developed dryer. The drying time (reduced moisture content up to 4%) was observed for the papaya pulp sample by employing Low-density polyethylene (LDPE), Polypropylene (PP), Polytetrafluoroethylene (PTFE), White Polyethylene Terephthalate (W-PET) and Transparent polyethylene terephthalate (T-PET) material as a membrane were 300, 330, 360, 330, and 300 min respectively. After thoroughly testing membrane materials properties, it is concluded that the T-PET membrane has superior thermal, mechanical, and optical properties. After an exhaustive examination of the marketplace scrutiny, the payback period was found to be 0.55 years. [ABSTRACT FROM AUTHOR]

To improve alkaline water electrolysis, catalyst coated diaphragms are prepared on Zirfon UTP 500 using polyvinylalcohol as a binder and Raney Ni and Pt (20% Pt/C; nanoparticular Pt) as catalysts to enhance the hydrogen evolution reaction. The catalyst coated diaphragms are tested under close to industrial conditions to assess their electrochemical performance and stability (60+ h). Raney Ni loaded diaphragms show 200 mV cell potential reduction at low temperature, and 150 mV at high temperature throughout the entire current density range. Nanoparticulate Pt and Pt/C loaded diaphragms perform well at low current densities (<30 mA/cm2), where a overpotential reduction of 150 mV is attained. At higher current densities (>30 mA/cm2) the reduction is smaller at only 50–100 mV throughout the entire temperature range, caused by an increase in Tafel slope. Long-term measurements and SEM/EDX show that the catalyst layers become unstable after several hours of experiments. [Display omitted] • Pt and Raney Ni coated diaphragms with PVA tested were under industrial conditions. • Flow cell measurements showed cell potential improvement of 100–150 mV. • Tafel slope for Pt in 27 wt% KOH small at low currents and large at high currents. • Raney Ni performed excellent throughout all temperature and current ranges. • Stability tests of up to 60 h were conducted. [ABSTRACT FROM AUTHOR]

This study loaded different amounts of UiO‐66‐NH2 onto sulfonated polyphenylene sulfide fibers (SPPS), successfully loading UiO‐66‐NH2 on SPPS fibers confirmed by energy dispersive x‐ray spectroscopy, x‐ray diffraction, and Fourier transform infrared spectroscopy. The UiO‐66‐NH2‐X@SFM were then impregnated in Nafion solution to obtain UiO‐66‐NH2‐X@SFM/Nafion composite membranes. The thermal stability, dimensional stability, mechanical properties, proton conductivity, methanol resistance, and other properties of the UiO‐66‐NH2‐X@SFM/Nafion composite membranes were subsequently comprehensively characterized. The proton conductivity of the UiO‐66‐NH2‐8@SFM/Nafion composite membrane at 80°C and 100% RH was measured to be 0.286 S cm−1, which exhibited a significant enhancement of 1.75 times compared with the original membrane. Simultaneously, the composite membrane demonstrated a remarkable reduction in methanol permeation rate. At 40°C and 100% RH, the UiO‐66‐NH2‐8@SFM/Nafion composite membrane has a selectivity of up to 20.7 × 104 S s cm−3 and a single cell density of 88.3 m W cm−2 at 60°C and 100% RH. [ABSTRACT FROM AUTHOR]

Critical water crisis due to overpopulation, industrialization and urbanization has resulted to the shortfall of providing safe drinking water to one billion people in the world. This work intends to fabricate modified hydrophobic polyvinylidene fluoride (PVDF) membrane by hydrophilic chitosan extracted from waste fish scales for wastewater treatment. Chitosan was blended with PVDF in N-methyl-2-pyrrolidone solution by solution casting method. Three different concentrations of 1, 3 and 5 wt% of chitosan were taken. The morphological, spectral and thermal analysis of the produced films were elaborately studied. The contact angle decreased with the increase of chitosan content from 82.64° to 60.97°. The tensile strength decreases from 1.11 to 0.38 MPa and Young’s modulus decreased from 12.08 to 7.4 MPa with increase in chitosan content in the film from 1 to 3 %. The performance of microparticle embedded membrane was compared with the pristine PVDF membrane, and it was affirmed that the microsized-chitosan embedded PVDF membrane manifests a broad promising application perspective towards wastewater treatment owing to its excellent water flux (76 L m−2 h−1) as well as antibacterial properties. [ABSTRACT FROM AUTHOR]

The global population is increasing, and emerging technologies have led to an unprecedented rise in worldwide energy consumption. Moreover, there is an urgent need to decrease the emission of harmful greenhouse gases linked to the utilization of fossil fuel reserves, which are depleted rapidly. In this context, polymer electrolyte membrane (PEM) fuel cells have emerged as the most promising energy source. One innovative energy system with significant potential is the direct borohydride fuel cell (DBFC), which offers a remarkable energy storage and conversion capacity. This technology has gained significant attention due to its impressive theoretical specific energy, convenient storage capabilities, and environmentally friendly characteristics. The distinctive capabilities of this technology have attracted the interest of both academic and industrial domains, owing to its versatile applicability across a broad spectrum of applications. This article provides thorough insights into the types of PEMs, catalysts, and factors limiting their practical applications in DBFCs. The mechanism of fuel oxidation, degradation, and mitigation measures of PEM in DBFCs are discussed in detail. By highlighting the notable advantages of PEMs in DBFCs, such as their permeability and minimal fuel crossover, ion conductivity, and stability, we demonstrate the significant potential of PEM membranes in DBFCs. Additionally, we have presented several representative examples that showcase the diverse range of potential applications for PEM membranes in fuel cells. Finally, we have addressed key challenges in this field, providing valuable insights for future research endeavours. • Recent advances in polymer electrolyte membranes and catalysts in direct borohydride fuel cell applications are summarized. • The working mechanism, elemental relationship, and transport coefficients are thoroughly elaborated. • Emphasis is targeted on the degradation of membranes in the long run and their mitigation strategies. • Practical viability and sustainability constraints and suggestions are also discussed. [ABSTRACT FROM AUTHOR]

Membrane separation processes play a crucial role in gas separation applications, with the need for ongoing development to fulfill new needs for today's challenges. For this purpose, novel 2D nanomaterials are progressively showing promise over conventional polymer‐based membrane material, exhibiting excellent molecular transport properties. Beyond the 2D materials already studied in this field, this article presents the first gas separation performances of vanadium pentoxide membrane. Brand new in gas separation topic, 2D van der Waals nanoribbons of V2O5 are successfully synthesized and layered on an anodic aluminum oxide substrate. Gas permeation analysis of He, N2, and CO2 are performed on various membranes made from different quantities of the nanomaterial. Gas permeance results suggest a deviation from an expected Knudsen diffusion mechanism of the V2O5‐based membrane for He separation. The ideal selectivities of He/N2 and He/CO2 are compared to Robeson's upper bound for polymeric membranes. V2O5 membranes, prepared with the highest V2O5 quantity, exceeded the upper bound from 2008 for He/N2 and 2019 (the most recent) for He/CO2, demonstrating the interesting potential of V2O5 2D materials for gas separation. [ABSTRACT FROM AUTHOR]

Vesicles bud from maturing Golgi cisternae in a programmed sequence. Budding is mediated by adaptors that recruit cargoes and facilitate vesicle biogenesis. In Saccharomyces cerevisiae, the AP-3 adaptor complex directs cargoes from the Golgi to the lysosomal vacuole. The AP-3 core consists of small and medium subunits complexed with two non-identical large subunits, ß3 (Apl6) and d (Apl5). The C-termini of ß3 and d were thought to be flexible hinges linking the core to ear domains that bind accessory proteins involved in vesicular transport. We found by computational modeling that the yeast ß3 and d hinges are intrinsically disordered and lack folded ear domains. When either hinge is truncated, AP-3 is recruited to the Golgi, but vesicle budding is impaired and cargoes normally sorted into the AP-3 pathway are mistargeted. This budding deficiency causes AP-3 to accumulate on ring-like Golgi structures adjacent to GGA adaptors that, in wild-type cells, bud vesicles downstream of AP-3 during Golgi maturation. Thus, each of the disordered hinges of yeast AP-3 has a crucial role in mediating transport vesicle formation at the Golgi. [ABSTRACT FROM AUTHOR]

Leishmaniasis is recognized as a serious public health problem in Brazil and around the world. The limited availability of drugs for treatment, added to the diversity of side effects and the emergence of resistant strains, shows the importance of research focused on the development of new molecules, thus contributing to treatments. Therefore, this work aimed to identify leishmanicidal compounds using a peptide dimerization strategy, as well as to understand their mechanisms of action. Herein, it was demonstrated that the dimerization of the peptide TSHa, (TSHa)2K, presented higher potency and selectivity than its monomeric form when evaluated against Leishmania mexicana and Leishmania amazonensis. Furthermore, these compounds are capable of inhibiting the parasite cysteine protease, an important target explored for the development of antileishmanial compounds, as well as to selectively interact with the parasite membranes, as demonstrated by flow cytometry, permeabilization, and fluorescence microscopy experiments. Based on this, the identified molecules are candidates for use in in vivo studies with animal models to combat leishmaniasis. [ABSTRACT FROM AUTHOR]

Mitochondria are dynamic, intracellular organelles with a separate genome originating from prokaryotes. They perform numerous functions essential for cellular metabolism and energy production. Mitochondrial‐derived vesicles (MDVs) are single or double membrane‐enclosed vesicles, formed and released from the mitochondrial sub‐compartments into the cytosol, in response to various triggers. MDVs interact with other organelles such as lysosomes and peroxisomes or may be incorporated and excreted via extracellular vesicles (EVs). MDVs selectively incorporate diverse protein and lipid cargoes and are involved in various functions such as mitochondrial quality control, immunomodulation, energy complementation, and compartmentalization and transport. This review aims to provide a summary of the current knowledge of MDVs biogenesis, release, cargoes, and roles. [ABSTRACT FROM AUTHOR]

Microfluidic devices have been the subject of considerable attention in recent years. The development of novel microfluidic devices, their evaluation, and their validation requires simulations. While common methods based on Computational Fluid Dynamics (CFD) can be time-consuming, 1D simulation provides an appealing alternative that leads to efficient results with reasonable quality. Current 1D simulation tools cover specific microfluidic applications; however, these tools are still rare and not widely adopted. There is a need for a more versatile and adaptable tool that covers novel applications, like mixing and the addition of membranes, and allows easy extension, resulting in one comprehensive 1D simulation tool for microfluidic devices. In this work, we present an open-source, modular, and extendable 1D simulation approach for microfluidic devices, which is available as an open-source software package at https://github.com/cda-tum/mmft-modular-1D-simulator. To this end, we propose an implementation that consists of a base module (providing the core functionality) that can be extended with dedicated application-specific modules (providing dedicated support for common microfluidic applications such as mixing, droplets, membranes, etc.). Case studies show that this indeed allows to efficiently simulate a broad spectrum of microfluidic applications in a quality that matches previous results or even fabricated devices. [ABSTRACT FROM AUTHOR]

Summary: Tannins, which are known as anti‐nutrient compounds with capability of limiting proteins and minerals bioavailability, are present in Persian gum. Ultrafiltration (UF, polysulfone membrane, 30 and 90 kDa, 1, 2 and 5 bar) and nanofiltration (NF, polysulfone, 400 Da, 2.5 and 5 bar) were used to remove tannin from the soluble fraction of Persian gum. The results revealed that the highest amount of tannin removal was achieved in UF (5 bar) and NF (5 bar). However, the use of the membrane process significantly decreased the apparent viscosity of the permeate, which might have an undesirable effect on the functionality of the gum. The effects of membrane molecular weight cut‐off, feed temperature, ultrasound pre‐treatment, feed concentration and pH, on the amount of tannic acid reduction, and changes in permeate flux, volume concentration factor difference, tannin reduction efficiency, and permeate apparent viscosity were evaluated. The results showed that total tannin removal efficiency was increased by ultrasound pre‐treatment, reduction of feed pH, and higher membrane molecular weight cut‐off. Increasing the feed temperature and concentration enhanced the apparent viscosity of permeate, although its value was lower than the control sample. [ABSTRACT FROM AUTHOR]

Background: The subcellular distribution of CD30 on mast cells and the presence of eosinophils in cutaneous mastocytosis require further investigation, especially as the cell surface expression of CD30 is critical for the therapeutic response of systemic mastocytosis to brentuximab vedotin. Objective: Investigation of 147 biopsy specimens from 143 patients with cutaneous mastocytosis for mast cell density and distribution, frequency of CD30 expression, CD30 staining patterns, and presence and distribution of eosinophils. Correlation with clinical patterns. Methods: Retrospective multicenter immunohistochemical study of CD30 expression, eosinophils and basic clinical data in cutaneous mastocytosis. Results: CD30 expression was found in all samples (cut‐off: ≥1%), whereby the staining was predominantly cytoplasmic in 99% of the samples. Additional membrane staining was detected in 62% of the samples. Surface expression of CD30 was more common in biopsy specimens with a high mast cell burden and in biopsy specimens with a higher CD30 expression rate. Eosinophils were admixed in 58% of the samples. Females and older patients showed a trend of a lower mast cell burden. Limitations: Retrospective study on formalin‐fixed and paraffin‐embedded tissue without functional analysis. Conclusion: Most cases of cutaneous mastocytosis show cell surface expression of CD30 expression and is, therefore, in principle, accessible for therapy with antibodies against CD30, provided the overall situation of the patient warrants. [ABSTRACT FROM AUTHOR]

The metabolites synthesized by plants to protect themselves serves as natural antimicrobial agents used in biomaterials. In this study, avocado oil (AO), was incorporated as a plant source and natural antimicrobial agent into polycaprolactone (PCL) membranes. The effects of varying AO ratios (25, 50, and 100 wt%.—PCL@25AO, PCL@50AO, PCL@100AO) on PCL membrane morphology, chemical structure, wettability, antimicrobial activity, and cell viabilities were investigated. It was demonstrated that the AO acts as a pore‐forming agent in solvent‐casted membranes. Young's modulus of the membranes varied between 602.68 and 31.92 MPa and more flexible membranes were obtained with increasing AO content. Inhibition zones of AO were recorded between 7.86 and 13.97 mm against clinically relevant microbial strains including bacteria, yeast, and fungi. Antimicrobial activity of AO was retained in PCL membranes at all ratios. Resazurin assay indicated that PCL@25AO membranes were cytocompatible with mouse fibroblast cells (L929 cell line) on day 6 showing 72.4% cell viability with respect to neat PCL membranes. Viability results were supported by scanning electron microscopy images and DAPI staining. The overall results of this study highlight the potential of PCL@25AO membranes as a biomaterial with antimicrobial properties, cytocompatibility, and mechanical strength suitable for various biomedical applications. [ABSTRACT FROM AUTHOR]

Rubber (cis-1,4-polyisoprene) is produced in cytosolic unilamellar vesicles called rubber particles (RPs), and the protein complex responsible for this synthesis, the rubber transferase (RTase), is embedded in, or tethered to, the membranes of these RPs. Solubilized enzyme activity is very difficult to achieve because the polymerization of highly hydrophilic substrates into hydrophobic polymers requires a polar/non-polar interface and a hydrophobic compartment. Using guayule (Parthenium argentatum) as a model rubber-producing species, we optimized methods to isolate RP unilamellear membranes and then a subset of membrane microdomains (detergent-resistant membranes) likely to contain protein complexes such as RTase. The phospholipid and sterol composition of these membranes and microdomains were analyzed using thin-layer chromatography (TLC) and liquid chromatography tandem mass spectroscopy (LC-MS/MS). Our data indicate that RP membranes consist predominantly of phosphatidic acid-containing membrane microdomains (DRMs or "lipid rafts"). Proteomic analyses of guayule RP membranes and membrane microdomains identified 80 putative membrane proteins covering 30 functional categories. From this population, we have tentatively identified several proteins in multiple functional domains associated with membrane microdomains which may be critical to RTase function. Definition of the mechanisms underlying rubber synthesis will provide targets for both metabolic engineering and breeding strategies designed to increase natural rubber production in latex-producing species. [ABSTRACT FROM AUTHOR]

Shrimp and crab shells are the most promising and viable source of raw material for the manufacturing of chitin and its derivatives. In-depth understanding of the biological properties of chitin and scientific advancements in the field of nanotechnology have enabled the development of high-performance chitin nanomaterials. Nanoscale chitin is of great economic value as a functional and reinforcement material for a wide range of applications including water purification. The use of nano-chitin to produce (bio) nanocomposites offers a good opportunity to prepare membrane materials with enhanced functional and structural properties. Chitosan-based membranes are found to be effective in water purification for the removal of pollutants like organic wastes, heavy metals, antibiotics, pathogenic microbes and acid waste. These membranes are environmentally friendly and can be used as a method to reduce humic acid waste from the aquatic environment. This review focuses on the preparation, characterization and chemical modification of nano chitin membrane and its application for water purification and water treatment. [ABSTRACT FROM AUTHOR]

Organic solvent reverse osmosis (OSRO) is an emerging and promising technology for the separation of organic mixtures, which is realized by differential transport rates of organics through polymer membranes. However, the solvent transport characteristics and separation mechanism within OSRO systems remain unclear. Herein, we investigate the solvent transport behavior in polymer membranes with intrinsic microporosity by combining nonequilibrium molecular dynamics simulations with solvent permeation examinations. The results indicate that organic molecules permeate through the micropores in a clustered state driven by both pressure and concentration gradients. The selectivity of solvents is co‐determined by their sorption and diffusion in the swollen polymer membranes with a microporous character. The sorption selectivity is predominant in the overall selectivity toward polar ethyl ether/n‐butanol separation, whereas diffusion selectivity is more critical in nonpolar 1,3,5‐triisopropylbenzene/toluene separation. Generally, this work provides valuable insights into the development of next‐generation OSRO membranes for solvent separation. [ABSTRACT FROM AUTHOR]

Transforming atmospheric water vapor into liquid form can be a way to supply water to arid regions for uses such as drinking water, thermal management, and hydrogen generation. Many current methods rely on solid sorbents that cycle between capture and release at slow rates. We envision a radically different approach where water is transformed and directly captured into a liquid salt solution that is suitable for subsequent distillation or other processing using existing methods. In contrast to other methods utilizing hydrogels as sorbents, we do not store water within hydrogels--we use them as a transport medium. Inspired by nature, we capture atmospheric water through a hydrogel membrane "skin" at an extraordinarily high rate of 5.50 kgm-2 d-1 at a low humidity of 35%. and up to 16.9 kgm-2 d-1 at higher humidities. For a drinking-water application, calculated performance of a hypothetical one-square-meter device shows that water could be supplied to two to three people in arid environments. This work is a significant step toward providing new resources and possibilities to water-scarce regions. [ABSTRACT FROM AUTHOR]

Exploration for sustainable energy resources is essential to minimize the dependence on fossil fuels and to improve environmental parameters. Here, the possibility of utilizing bio‐waste‐derived electrolytes as an electrical energy resource by placing them across semipermeable membranes prepared through parallel stacking of coir fibers is examined. The nanofluidic membrane (d‐CF‐V) prepared by modifying the inner walls of the bio‐fluidic channels with atomically thin layers of vanadium pentoxide (VO) shows excellent perm‐selectivity (t+ = 0.87, with 1000‐fold concentration difference) and electricity conversion efficiency (≈ 28.2%). With simulated sea and river water, the d‐CF‐V yields output energy up to 2.4 W m−2, similarly with mineral acid bases (0.5 m HCl and 0.01 m NaOH), the d‐CF‐V shows an energy output of 11.8 W m−2. The sun‐dried Garcinia morella (Kuji thekera), and charred peels of Musa balbisiana (banana) are used as sustainable sources of bio‐electrolytes, which in combination with permselective d‐CF‐V yielded a power density of ≈1.4 W m−2. By replacing standard Ag/AgCl electrodes with nanomaterials exhibiting contrasting charge transfer activities, oxidized carbon nanotube membrane (o‐CNT) and polyaniline (PANI) membrane the output voltage is enhanced from –127 to –568 mV and current output is increased from 10.2 to 51.5 µA. [ABSTRACT FROM AUTHOR]

Bioinspired smart surfaces, such as slippery liquid‐infused porous surfaces (SLIPS), have garnered significant attention due to their efficacy in self‐cleaning, antifouling, and antibacterial applications. Despite their advantages, SLIPS exhibit limitations such as compromised transparency, insufficient stability, and limited slippery performance, which have hindered their widespread practical use. To address these challenges, this article proposes a rational design utilizing a void‐centered poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF) membrane for slippery liquid‐infused porous surfaces with exceptional flexibility, transparency, durability, and superior slippery performance. These advancements promise to enhance high‐performance, self‐cleaning, and antifogging coatings. The membranes, featuring large‐area, thickness‐customizable void‐centered PVDF, are fabricated through a two‐step process involving phase separation and selective etching. The utilization of PVDF polymer, which has a refractive index similar to that of silicon‐based lubricant oil, enhances transparency, while macrovoids positioned at the membrane's center, acting as oil reservoirs, improve the stability and performance of the SLIPS surfaces. Experimental findings demonstrate remarkable transparency of up to 93% in the visible light range and a lubricant oil uptake of 2.32 at a porosity of 70%. Moreover, the developed SLIPS exhibit outstanding durability, maintaining slippery performance with sliding angles of <10° following exposure to either 400 consecutive droplets or aging for up to 40 days. This study significantly contributes to the development of future SLIPS, particularly for applications such as antifogging coatings on vehicle glass and solar panels, and self‐cleaning surfaces. [ABSTRACT FROM AUTHOR]

The lipophilization of polyphenols (phenolipids) may increase their affinity for membranes, leading to better antioxidant protection. Cholesteryl esters of caffeic, dihydrocaffeic, homoprotocatechuic and protocatechuic acids were synthetized in a one-step procedure with good to excellent yields of ~50–95%. After evaluation of their radical scavenging capacity by the DPPH method and establishing the anodic peak potential by cyclic voltammetry, their antioxidant capacity against AAPH-induced oxidative stress in soybean PC liposomes was determined. Their interaction with the liposomal membrane was studied with the aid of three fluorescence probes located at different depths in the membrane. The cholesteryl esters showed a better or similar radical scavenging capacity to that of α-tocopherol and a lower anodic peak potential than the corresponding parental phenolic acids. Cholesteryl esters were able to protect liposomes to a similar or greater extent than α-tocopherol. However, despite their antiradical capacity and being able to penetrate and orientate in the membrane in a parallel position to phospholipids, the antioxidant efficiency of cholesteryl esters was deeply dependent on the phenolipid polyphenolic moiety structure. When incorporated during liposome preparation, cholesteryl protocatechuate and caffeate showed more than double the activity of α-tocopherol. Thus, cholesteryl phenolipids may protect biomembranes against oxidative stress to a greater extent than α-tocopherol. [ABSTRACT FROM AUTHOR]

The separation of used engine oil (UEO) with an ultrafiltration (UF) membrane made of commercial copolymer of poly(acrylonitrile-co-methyl acrylate) (P(AN-co-MA)) has been investigated. The P(AN-co-MA) sample was characterized by using FTIR spectroscopy, 13C NMR spectroscopy, and XRD. The UF membrane with a mean pore size of 23 nm was fabricated by using of non-solvent-induced phase separation method—the casting solution of 13 wt.% P(AN-co-MA) in dimethylsulfoxide (DMSO) was precipitated in the water bath. Before the experiment, the used engine oil was diluted with toluene, and the resulting UEO solution in toluene (100 g/L) was filtered through the UF membrane in the dead-end filtration mode. Special attention was given to the evaluation of membrane fouling; for instance, the permeability of UEO solution was dropped from its initial value of 2.90 L/(m2·h·bar) and then leveled off at 0.75 L/(m2·h·bar). However, the membrane cleaning (washing with toluene) allowed a recovery of 79% of the initial pure toluene flux (flux recovery ratio), indicating quite attractive membrane resistance toward irreversible fouling with engine oil components. The analysis of the feed, retentate, and permeate by various analytical methods showed that the filtration through the UF membrane made of P(AN-co-MA) provided the removal of major contaminants of used engine oil including polymerization products and metals (rejection—96.3%). [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Clinical Considerations Conclusions Clinical Significance Acute traumatic defects in the esthetic zone pose a significant challenge in dental implant rehabilitation, requiring innovative techniques to achieve optimal functional and esthetic outcomes. This article investigates the use of a novel combination of root submergence and guided bone regeneration (GBR) to address these defects. The goal is to evaluate the potential of this integrated approach for achieving predictable bone regeneration and long‐term tissue stability.Studies have shown significant improvements in soft‐tissue contour, papilla preservation, and emergence profile when root submergence is employed. Despite these benefits, the integration of root submergence with GBR remains underexplored in the literature. This combination shows considerable potential for achieving predictable bone regeneration and sustaining tissue stability in the esthetic zone.The integration of root submergence with GBR offers a promising solution for managing traumatic defects in the esthetic zone by enhancing soft‐tissue contours and facilitating predictable bone regeneration. However, additional clinical studies are needed to support the long‐term success of this innovative approach in dental implant rehabilitation.The combined use of root submergence and GBR for treating acute traumatic defects in the esthetic zone represents a notable advancement in dental implant rehabilitation. This article presents a detailed analysis of the rationale, technique, and clinical outcomes of this approach, underscoring its importance in achieving optimal esthetic and functional outcomes for patients with complex clinical needs. [ABSTRACT FROM AUTHOR]

Self‐organizing protein patterns are crucial for living systems, governing important cellular processes such as polarization and division. While the field of protein self‐organization has reached a point where basic pattern‐forming mechanisms can be reconstituted in vitro using purified proteins, understanding how cells can dynamically switch and modulate these patterns, especially when transiently needed, remains an interesting frontier. Here, we demonstrate the efficient regulation of self‐organizing protein patterns through the modulation of simple biophysical membrane parameters. Our investigation focuses on the impact of membrane affinity changes on Min protein patterns at lipid membranes composed of Escherichia coli lipids or minimal lipid compositions, and we present three major results. First, we observed the emergence of a diverse array of pattern phenotypes, ranging from waves over flower‐shaped patterns to snowflake‐like structures. Second, we demonstrated the dependency of these patterns on the density of protein‐membrane linkers. Finally, we demonstrate that the shape of snowflake‐like patterns is fine‐tuned by membrane charge. Our results demonstrate the significant influence of membrane linkage as a straightforward biophysical parameter governing protein pattern formation. Our research points towards a simple yet intriguing mechanism by which cells can adeptly tune and switch protein patterns on the mesoscale. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) membranes have been widely studied and used for gas separation processes, but some structural changes are necessary to guarantee high membrane selectivities. The thermal reduction process stands out for reducing the interlayer channel size of the GO nanosheets to improve the molecular sieving mechanism. Herein, thermally annealed GO layers were deposited on the outer surface of porous alumina hollow fiber substrates and the produced composite membranes were tested for selective hydrogen (H 2) separations. The influence of the thermal annealing process at different mild temperatures (80 and 160 °C) on the characteristics of the GO structure was investigated towards the improvement of the membrane efficiency for H 2 separation. ATR-FTIR results confirmed the elimination of oxygenated groups, and XRD analyses showed the GO interlayer space decreased from 8.71 to 7.38 Å after the thermal annealing process at 160 °C. The GO thermally annealed membrane presented an H 2 permeance of 2032.47 ± 101.69 GPU and an H 2 /N 2 selectivity of 12.16 ± 0.30, which is 315% greater than the selectivity of the pristine GO membrane. Hence, the application of the thermal reduction method to produce GO membranes with greater selectivities is a viable alternative to deal with gas separation processes. • A thin graphene oxide (GO) layer was deposited on asymmetric Al 2 O 3 hollow fibers. • Thermal treatment at 160 °C produced a quasi-reduced GO membrane. • The GO d-space decreased with the thermal treatment at a mild temperature of 160 °C. • H 2 /CO 2 and H 2 /N 2 selectivities were boosted with the thermal treatment. [ABSTRACT FROM AUTHOR]

As electronic devices tend to be an integrated, intelligent, and lightweight development, the need to develop lightweight, low-reflective electromagnetic interference (EMI) shielding materials for wearable and portable electronic devices and other emerging areas of electromagnetic shielding is particularly critical. Currently, absorption-dominated shielding materials mainly focus on three-dimensional porous materials such as aerogels and foams, which cannot meet the increasing needs of light and thin requirements. Herein, an electromagnetic shielding composite membrane featured with an asymmetric structure was constructed by different electrical–magnetic gradients of cellulose nanofiber (CNF)/carbon nanotubes (CNTs)/cobalt tetroxideferrate (CoFe2O4) multilayers combined with a layer of CNF/silver-plated aramid fibers (Ag-AFs) through a facile vacuum-assisted filtration (AVF) process. The CNF/Ag-AFs layer acts as a reflection layer at the bottom to block the transmitted electromagnetic wave. The absorption layer consists of three layers of a CNF/CNTs/CoFe2O4 membrane, where the dual electromagnetic gradients were constructed by changing the ratio of CNTs and CoFe2O4 in each layer. The whole composite membrane exhibits tightly stacked multilayer microstructures. Owing to the unique structural design, this CACC-D membrane has an increasing conductive gradient and decreasing permeable gradient along the direction of electromagnetic wave incidence and achieves an average EMI SE of 31.52 dB (>99.9%) in the X-band, and the reflectivity is as low as 0.40 at the thickness of only 144 μm, fully realizing the absorption-dominated shielding mechanism. In addition, the composite membrane has a stable thermal property and fascinating mechanical properties, with a high breaking strength of 30.59 MPa and can recover quickly after 180° bending. We believe that this work provides ideas for the preparation of thin, lightweight, and high EMI shielding performance materials. [ABSTRACT FROM AUTHOR]

Aromatic amine-supported N-functionalization of graphene oxide (GO) was carried out via aniline vapor exposure for different durations (15–240 min), and the repercussions on the strontium (Sr-(II)) adsorption ability of nanoscale-thick GO membranes (0.1–0.5 mg) were investigated. Characterization of aniline vapor-subjected GO substantiates significant amendments in the GO layer as well as functional group structures, restoration of the π-conjugation network, and integration of diverse N moieties, including precursor aniline molecules and its derivatives. Incorporation of aniline derivatives escalated the Sr-(II) adsorption ability of the GO membrane from ∼310 to ∼600 mg/g and induced Sr-(II) preferential sites that facilitate ∼540 mg/g adsorption, even in the presence of competing Mg2+/Ba2+ ions. Aniline-subjected GO membranes displayed a cumulative Sr-(II) sorption capacity of ∼1500 mg/g via multiple filtration cycles, a notable Sr-(II) desorption of ∼25%, and an overall adsorption capacity of ∼1295 mg/g when subjected to multiple (Sr2+/Mg2+/Ba2+) ions. Further, the pronounced enhancement in the Sr adsorption capacity of aniline-subjected GO nanoparticle (GONP) membranes reiterated the affinity of N-group-amended GO layers toward Sr2+ ions despite the limitations on surface area. These aniline-supported N-functionalization and Sr-(II) sorption studies unveil the efficiency of the acquiescent aromatic ring allied with the electron-donating amine group in generation of abundant/versatile N moieties and the resultant enhancement of Sr-(II) adsorption ability. [ABSTRACT FROM AUTHOR]

Rough endoplasmic reticulum (ER) sheets are a fundamental domain of the ER and the gateway into the secretory pathway. Although reticulon proteins stabilize high-curvature ER tubules, it is unclear whether other proteins scaffold the flat membranes of rough ER sheets. Through a proteomics screen using ER sheet-localized RNA-binding proteins as bait, we identify the sigma-1 receptor (SigmaR1) as an ER sheet-shaping factor. High-resolution live cell imaging and electron tomography assign SigmaR1 as an ER sheet-localized factor whose levels determine the amount of rough ER sheets in cells. Structure-guided mutagenesis and in vitro reconstitution on giant unilamellar vesicles further support a mechanism whereby SigmaR1 oligomers use their extended arrays of amphipathic helices to bind and flatten the lumenal leaflet of ER membranes to oppose membrane curvature and stabilize rough ER sheets. [Display omitted] • SigmaR1 and RNA-binding proteins Lyric and Lrrc59 partition into ER sheets • Changing SigmaR1 levels alters the balance of ER sheets and tubules in cells • SigmaR1 proliferates polyribosome-studded rough ER sheets • The flat lumenal surface of SigmaR1 oligomers opposes tubulation in vivo and in vitro Sawyer et al. utilize high-resolution fluorescence microscopy and EM tomography in cells in combination with a minimal in vitro reconstitution system to identify SigmaR1 as an integral ER membrane protein complex that is necessary and sufficient to stabilize rough ER sheets and oppose tubule formation. [ABSTRACT FROM AUTHOR]

Vapor phase infiltration (VPI) has emerged as a promising tool for fabrication of novel hybrid materials. In the field of polymeric gas separation membranes, a beneficial impact on stability and membrane performance is known for several polymers with differing functional groups. This study for the first time investigates VPI of trimethylaluminum (TMA) into poly(1‐trimethylsilyl‐1‐propyne) (PTMSP), featuring a carbon–carbon double bond as functional group. Saturation of the precursor inside the polymer is already attained after 60 s infiltration time leading to significant densification of the material. Depth profiling proves accumulation of aluminum in the polymer itself, but a significantly increased accumulation is visible in the gradient layer between polymer and SiO2 substrate. A reaction pathway is proposed and supplemented by density‐functional theory (DFT) calculations. Infrared spectra derived from both experiments and simulation support the presented reaction pathway. In terms of permeance, a favorable impact on selectivity is observed for infiltration times up to 1 s. Longer infiltration times yield greatly reduced permeance values close or even below the detection limit of the measurement device. The present results of this study set a strong basis for the application of VPI on polymers for gas‐barrier and membrane applications in the future. [ABSTRACT FROM AUTHOR]

Background A rapid expansion of study on platelet-rich fibrin (PRF) has gained more attention in the subject. In this study, bibliometrics were used to assess the outputs and trends of relevant PRF studies. An in-depth analysis of the publication patterns and progress in PRF research worldwide was conducted for the purpose of filling in this research gap. Materials and Methods The analysis included 946 papers sourced from Web of Science that included 842 original articles and 104 reviews. A number of factors including country/region, institution, journal, and author were taken into account. Research on PRF development trends was mapped using the frequency of keywords. Results In terms of the total number of publications, China ranked first with 199 papers, whereas the United States ranked first on the H-index with 37. PRF is an active research area in stomatology and craniomaxillofacial surgery. Keywords provided by the authors were designated to three clusters: red, green, and blue. "Growth factor," "platelet-rich plasma," and "bone regeneration" were the most frequent keywords in each cluster, which reflect the current interests in corresponding fields. Bone regeneration post-dental extractions is one of the main application directions in the field of oral and maxillofacial surgery. "Membrane," "injectable PRF (I-PRF)," "case report," and "advanced PRF (A-PRF)" were relative recent keywords in all clusters, indicating that manufacturing processes and new applications are promising research hotspots in the field. Conclusion In the future, the applications of modified PRF, such as I-PRF, are promising research hotspots. Moreover, strict randomized controlled trials on PRF deserve more attention. The results of this analysis may be helpful for all scholars seeking to expand researches and innovations in the field of PRF. [ABSTRACT FROM AUTHOR]

Pervaporation has been a central subject in the research community within the scope of the further development of energy- and cost-efficient alternatives to conventional liquid–liquid separation technologies. The potential eligibility of four commercial membranes (ZEBREX ZX0, PERVAPTM 4155-80, PERVAPTM 4100, PERVAPTM 4101) for use in an integrated dehydration application of a diethyl carbonate/water/ethanol mixture by pervaporation was assessed experimentally. The impact of feed concentration, operating temperature, pressure, and sweep gas flow rate on membrane separation performance, including permeation flux, permeate quality, selectivity, and permeance, was thoroughly investigated. Applying the ZX0 membrane delivered the best qualities of all tested membranes of the permeate stream, with a water concentration of mostly >98%. In comparing the water flux, the ZX0 membrane remained reasonably competitive with the polymer membranes. Furthermore, the sweep gas volume flow rate and the operating temperature were identified as influencing the flux significantly but not the product composition. At the same time, the feed concentration of water also influenced the water purity within the permeate. The experiments were monitored with a partial least squares model, allowing a quick assessment of obtained samples while delivering accurate results. [ABSTRACT FROM AUTHOR]

Chronic subdural hematoma (CSDH) is a prevalent neurosurgical condition characterized by blood accumulation within the border cell layer. Despite various treatment options—medical, endovascular, and surgical—recurrence rates remain high. Our pilot study investigates the safety and efficacy of endoscopic membranectomy (EM) in reducing recurrence in nonhomogenous CSDH. This was a prospective single-arm interventional pilot study from March to June 2023. It included patients of all ages who presented with symptomatic nonhomogenous CSDH requiring surgical intervention. A total of 19 patients were enrolled in this study. The average age was 60.4 ± 10.4 years. The male:female ratio was 5.3:1. In this group, 73.7% (n = 14) of patients had a history of trauma. All patients presented with a history of altered sensorium and contralateral limb weakness. The most common type of CSDH was trabecular (42.1%), followed by gradient (21%), separated (15.8%), and laminar (15.8%). The average duration of surgery was 43.42 ± 10 minutes. CSDH may be thin or thick based on its tractability and has significance in EM technique. All patients started recovering within 24 hours. All patients were asymptomatic, without any neurologic deficit, at 2 weeks, and remained so at the 6-month review. In 17 patients, the 6-month follow-up computed tomography did not show any bleeding/recurrence. There were no postoperative seizures, wound-healing issues, or infections. There are multiple treatment options for CSDH at present. EM is a potentially safe and effective treatment for CSDH, with lower recurrence and faster recovery. Large-scale controlled studies on EM are required. [ABSTRACT FROM AUTHOR]

This study investigates simulation of pharmaceutical separation via membrane distillation process by computational simulation and machine learning modeling strategy. The efficacy of three regression models, i.e., Multi-layer Perceptron (MLP), Gamma Regression, and Support Vector Regression (SVR) in predicting the solute concentration, C(mol/m³), was evaluated. The hyper-parameters were optimized by fine-tuning the models using the Red Deer Algorithm (RDA). Computational analyses were carried out for removal of pharmaceuticals from solution by membrane distillation in continuous mode. Mass transfer and machine learning models were implemented focusing on concentration of solute in the feed section of membrane. Results indicate that the Multi-layer Perceptron model achieved great accuracy with an R2 of 0.9955, an MAE of 0.0084, and an RMSE of 0.0148, effectively capturing complex nonlinear relationships in the data. Gamma Regression also performed acceptably, with fitting R2 of 0.9214, showing its suitability for positively skewed data. The Support Vector Regression model, while capturing the general trend, showed the lowest performance with an R2 of 0.8710. These findings suggest that the Multi-layer Perceptron is the most accurate model for this dataset, followed by Gamma Regression and Support Vector Regression. This underscores the importance of careful model selection and optimization in regression analysis in combination with computational simulation of membrane processes. [ABSTRACT FROM AUTHOR]

The cold sintering process (CSP) was used to produce membranes and improve the densification of a geopolymer-zeolite matrix, fully recycling a waste geopolymer powder. The role of CSP parameters were studied varying temperature (25, 40 and 80°C), applied pressure (56 MPa and 168 MPa) and reactive solution (H 2 O, KOH or NaOH 2, 4, 6, 8 M). CSP applied on the waste geopolymer powder (molar ratio Si/Al = 2.0 and K/Al = 1.0) resulted in relative densities ranging from about 50–77%, while modal pores varied from 0.006 µm to 0.017 µm in the mesopore range. Compressive strength was up to 45 MPa. The addition of 10 wt% of the waste geopolymer powder to a geopolymer- zeolite powder containing 81% of in situ synthetized NaA phase allowed a densification approaching 70% with mechanical strength up to 7.4 MPa. • Membranes were produced by cold sintering process (CSP). • A waste geopolymer powder was recycled to produce membranes. • Relative densities were 50–77% and modal pores 0.006–0.017 µm. • CSP on a geopolymer-NaA zeolite powder allowed a densification approaching 70%. [ABSTRACT FROM AUTHOR]

Natural plant-derived compounds with broad-spectrum antimicrobial activity have become an effective strategy against multidrug-resistant bacteria. The present study was designed to compare the antibacterial activity of six chlorogenic acid (CA) isomers extracted from stevia and investigated the underlying antibacterial mechanisms involved. The results indicated that isochlorogenic acid C (ICAC) exhibited the strongest antibacterial activity against the tested bacteria, especially E. coli, at a 2 mg/mL minimum inhibitory concentration (MIC) and 8 mg/mL minimum bactericidal concentration (MBC). At the MBC, ICAC inhibited 72.66% of the clinical multidrug-resistant strains. Scanning electron microscopy (SEM) revealed that ICAC induced considerable morphological alterations in E. coli ATCC25922 and C4E2. The significant increase in the activity of extracellular alkaline phosphatase (AKP) indicated that ICAC damages the permeability of the bacterial cell wall. Additionally, the intracellular membrane (IM) permeability and the content of lipopolysaccharide (LPS), a main component of the outer membrane (OM), were determined. The significant decrease in LPS content and increased leakage of intracellular proteins and K+ from E. coli indicated that ICAC could induce the exfoliation of OM and disrupt IM permeability, resulting in the loss of barrier function. The uptake of propidium iodide (PI), a compromised cell membrane nucleic acid stain, and confocal laser scanning microscopy (CLSM) further demonstrated that ICAC disrupted IM integrity. Moreover, the bactericidal effect and damage to bacterial microstructural function occurred in a dose-dependent manner. These data demonstrate that ICAC has excellent antibacterial activity and is a promising approach for overcoming the antibiotic resistance of pathogenic bacteria. [ABSTRACT FROM AUTHOR]

Appropriate nutrient sources and optimized doses of plant nutrients for space and lunar farming have remained key challenges prompting investigations to sort out biologically viable options including human urine. Therefore, a trial was performed to compare the hydroponic growth of sugar beets using a standard nutrient solution and the same nutrient solution with a 10% replacement of an artificial urine solution that had been concentrated using direct contact membrane distillation (DCMD). The response variables included yield-contributing traits and root parameters (plant height, stem diameter, length and fresh weight of leaf and root, whole plant fresh weight), along with beet characteristics (diameter, length, and fresh weight at harvest). The results revealed that 10% synthetic urine treatment produced significantly taller plants (33%, 3%, and 8% at the 4th, 6th, and 10th week after sowing, respectively) and recorded 52% and 40% greater leaf width at the 4th and 6th weeks, respectively, compared to the control. In contrast, 10% replacement with synthetic urine in the nutrient performed statistically below par compared to the control treatment by producing 9% and 17% lower leaf width at the 8th and 10th weeks, respectively. Additionally, at the harvest, 10% synthetic urine treatment gave taller plants with greater stem length and root length (2.3%, 8.6%, and 59%, respectively) than the control. Moreover, the replacement treatment remained superior by showing higher root weight and stem diameter at harvest but performed below par compared to the control in leaf width and whole plant fresh weight. At harvest, both treatments remained statistically non-significant in terms of beet length, however the control surpassed synthetic urine treatment by yielding 37% and 103% higher width and fresh weight of beets, respectively. Based on recorded findings, it may be inferred that synthetic urine holds potential as a valuable plant nutrient source for producing sugar beets in an indoor hydroponic system, though not comparable in some respects with the control (standardized plant nutrient medium) for some plant measurements. [ABSTRACT FROM AUTHOR]

The deoxygenation process in water used in well injection operations is an important matter to eliminate corrosion in the petroleum industry. This study used molecular dynamics simulations to understand the behavior of siloxane surfaces by studying the surface properties with two functional groups attached to the end of siloxane and their effect on the deoxygenation process. The simulations were performed using LAMMPS to characterize surface properties. Jmol software version 14 was used to generate siloxane chains with (8, 20, and 35) repeat units. We evaluated properties such as total energy, surface tension, and viscosity. Then, we used siloxane as a membrane to compare the efficiency of deoxygenation for both types of functional groups. The results indicated that longer chain lengths increased the total energy and viscosity while decreasing surface tension. Replacing methyl groups with trifluoromethyl (CF3) groups increased all the above mentioned properties in varying proportions. Trifluoromethyl (CF3) groups showed better removal efficiency than methyl (CH3) groups but allowed more water to pass. Furthermore, the simulations were run using the class II potential developed by Sun, Rigby, and others within an explicit-atom (EA) model. This force field is universally applicable to the atomistic simulation of polymers, inorganic small molecules, and common organic molecules. [ABSTRACT FROM AUTHOR]

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A new type of separation materials for alkaline water electrolyzers has been obtained: a diaphragm synthesized by the phase inversion method and a multilayer microfilm membrane with zirconium hydroxide hydrogel as a hydrophilic filler. Experimental data on their porosity, electrical conductivity, and gas density, as well as the results of their tests as part of an alkaline electrolyzer battery are presented in comparison with a porous diaphragm based on polysulfone with a hydrophilic filler (TiO2), synthesized by the traditional phase inversion method. The advantages and disadvantages of new materials are assessed, and ways for further research and development are determined. [ABSTRACT FROM AUTHOR]

A new composite separation membrane was developed by using organically modified montmorillonite (OMMT) as an additive. The effects of OMMT on the modification and properties of PVDF composite membranes were investigated. It is found that different kinds and amounts of OMMT into the casting solution can obviously change the pure water flux, separation performance and hydrophilicity of composite membrane in varying degrees. When the TA/PDA-MMT was 0.5 wt%, the pure water flux of the membrane reached the maximum, which was 584.7 L/(m2·h), about 6 times that of the original membrane. The OMMT/PVDF composite membrane had good hydrophilicity and stability in the treatment of oily wastewater. The development of novel OMMT/PVDF composite membrane will provide a new idea for solving the problem of oily wastewater treatment. [ABSTRACT FROM AUTHOR]

Zeolites have been used as a separation membrane material by taking advantages of their unique adsorption properties and molecular sieving properties based on the micropores. Zeolite membranes are widely used in practical applications, mainly for dehydration of organic solvents. Furthermore, the research and development continue toward large-scale implementation in the energy and carbon neutral field. The high heat and chemical resistance of zeolite membranes are also expected to be utilized as membrane reactors. Zeolite membrane and membrane separation will contribute to the fulfillment of a carbon-neutral society through energy saving in separation, reaction, and CO2 recovery. In this review, the basic structure, the synthesis methods and the applications of zeolite membranes are introduced. The recent research trends of zeolite membrane in the research and applications are also explained. [ABSTRACT FROM AUTHOR]