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Aerosol microbiome studies have received increased attention as technological advancements have made it possible to dive deeper into the microbial diversity. To enhance biomass collection for metagenomic sequencing, long-term sampling is a common strategy. While the impact of prolonged sampling times on microorganisms' culturability and viability is well-established, its effect on nucleic acid stability remains less understood but is essential to ensure representative sample collection. This study evaluated four air samplers (SKC BioSampler, SASS3100, Coriolis μ, BioSpot-VIVAS 300-P) against a reference sampler (isopore membrane filters) to identify nucleic acid stability during long-term sampling. Physical sampling efficiencies determined with a fluorescent tracer for three particle sizes (0.8, 1, and 3 μm), revealed high efficiencies (> 80% relative to reference) for BioSampler, SASS3100, and BioSpot-VIVAS for all particle sizes, and for Coriolis with 3 μm particles. Coriolis exhibited lower efficiency for 0.8 μm (7%) and 1 μm (50%) particles. During 2-h sampling with MS2 and Pantoea agglomerans, liquid-based collection with Coriolis and BioSampler showed a decrease in nucleic acid yields for all test conditions. BioSpot-VIVAS displayed reduced sampling efficiency for P. agglomerans compared to MS2 and the other air samplers, while filter-based collection with SASS3100 and isopore membrane filters, showed indications of DNA degradation for 1 μm particles of P. agglomerans after long-term sampling. These findings show that long-term air sampling affects nucleic acid stability in both liquid- and filter-based collection methods. These results highlight bias produced by bioaerosol collection and should be considered when selecting an air sampler and interpreting aerosol microbiome data. [ABSTRACT FROM AUTHOR]

INTRODUCTION: The absence of a consistent downward G vector can make separation of gases from liquids challenging, such as in field medicine without stable upright equipment or during spaceflight. This limits the use of medical equipment and procedures like administration of intravenous (IV) fluids in microgravity and can make field medicine hazardous. Administering IV fluids and medications in microgravity requires a technique to separate air from the liquid phase. Current commercial filters for separation of gases are incompatible with high flow and blood. We present a novel filter designed to provide adequate air clearance without a consistent downward G vector. METHODS: I nline air-eliminating filters were designed for use with IV fluid tubing in microgravity using computer-aided design software and printed using nylon 12 on an EOS Selective Laser Sintering 3D printer. A 0.2-μm membrane filter was adhered around a central, hollow pillar with external spiral baffles allowing separation and venting of air from the fluid. Results were compared against commercially available inline air-eliminating filters. RESULTS: The 3D-printed filters outperformed the commercial filters in both percentage of air removed and flow rates. The centrifugal, baffled filter had flow rates that far exceeded the commercial filters during rapid transfusion. DISCUSSION: I V fluid administration is an often underappreciated and a necessary basic requirement for medical treatment. An air-eliminating filter compatible with blood and rapid transfusion was developed and validated with crystalloid solutions to allow the successful administration of IV fluid and medication without a consistent downward G vector. [ABSTRACT FROM AUTHOR]

A recent study published in the American Journal of Respiratory & Critical Care Medicine investigated the presence of nanoplastics in the human respiratory system. The study found that nanoplastics, specifically polyethylene (PE) and polypropylene (PP), were detected in the bronchoalveolar lavage fluid (BALF) of participants with respiratory diseases. The concentrations of PE and PP in the BALF samples were significantly higher than those in control samples. This study provides important insights into the presence of nanoplastics in the lower respiratory tract and highlights the need for further research on the potential adverse effects of nanoplastics on human health. [Extracted from the article]

Controlled environment agriculture has the potential to enhance agriculture sustainability, a United Nations sustainable development goal. Enclosed agricultural facilities can be used in locations that cannot support field agriculture while reducing water usage and increasing productivity relative to open field agriculture. The primary challenges with operation arise from energy consumption to maintain the proper growth conditions. Membrane processes can reduce energy consumption by controlling temperature, humidity, and carbon dioxide concentration. Membrane processes also can minimize water consumption by enabling the use of non-conventional water resources and reducing wastewater production. The literature describing these applications is reviewed and opportunities for future innovation are discussed. [ABSTRACT FROM AUTHOR]

In order to develop a standardized nomenclature for the mechanisms and materials utilized during extracorporeal blood purification, a consensus expert conference was convened in November 2022. Standardized nomenclature serves as a common language for reporting research findings, new device development, and education. It is also critically important to support patient safety, allow comparisons between techniques, materials, and devices, and be essential for defining and naming innovative technologies and classifying devices for regulatory approval. The multidisciplinary conference developed detailed descriptions of the performance characteristics of devices (membranes, filters, and sorbents), solute and fluid transport mechanisms, flow parameters, and methods of treatment evaluation. In addition, nomenclature for adsorptive blood purification techniques was proposed. This report summarizes these activities and highlights the need for standardization of nomenclature in the future to harmonize research, education, and innovation in extracorporeal blood purification therapies. [ABSTRACT FROM AUTHOR]

Globally, billions of people burn fuels indoors for cooking and heating, which contributes to millions of chronic illnesses and premature deaths annually. Additionally, residential burning contributes significantly to black carbon emissions, which have the highest global warming impacts after carbon dioxide and methane. In this study, we use Fourier transform infrared spectroscopy (FTIR) to analyze fine-particulate emissions collected on Teflon membrane filters from 15 cookstove types and 5 fuel types. Emissions from three fuel types (charcoal, kerosene, and red oak wood) were found to have enough FTIR spectral response for functional group (FG) analysis. We present distinct spectral profiles for particulate emissions of these three fuel types. We highlight the influential FGs constituting organic carbon (OC) using a multivariate statistical method and show that OC estimates by collocated FTIR and thermal–optical transmittance (TOT) are highly correlated, with a coefficient determination of 82.5 %. As FTIR analysis is fast and non-destructive and provides complementary FG information, the analysis method demonstrated herein can substantially reduce the need for thermal–optical measurements for source emissions. [ABSTRACT FROM AUTHOR]

Industrial wastewater from various manufacturing sectors poses a significant environmental concern due to the release of dyes, heavy metals, and pollutants into natural water streams. Effective treatment of large volumes of industrial wastewater is crucial to mitigate this issue. Conventional industrial wastewater filtration systems often prove to be inefficient, necessitating the exploration of alternative and cost‐effective water filtration methods. In this study, we drew inspiration from the natural adsorption and purification properties of corncob to develop a novel green composite membrane filter. The composite membrane filters, named MCAPCB and MCATPCB, were formulated by incorporating powdered corncob (PCB) and alkali/hydrogen peroxide‐treated powdered corncob (TPCB) into cellulose acetate. The adsorption properties of the composite filters were evaluated using UV–Vis spectrophotometry for dye adsorption and inductively coupled plasma optical emission spectroscopy (ICP‐OES) and atomic absorption spectroscopy (AAS) for heavy metal adsorption. The results demonstrated that MCATPCB20, incorporating 20 wt% TPCB, exhibited remarkable performance in the removal of methylene blue dye, with an adsorption efficiency of 97.46%. In comparison, MCAPCB20, incorporating 20 wt% PCB, achieved a dye adsorption efficiency of 80.15%. Moreover, MCATPCB20 displayed exceptional heavy metal removal capabilities, effectively rejecting 98% and 95% of cadmium and lead, respectively, from water samples containing 1 ppm of each metal. The composite filter membranes containing 20 wt% TPCB exhibited superior adsorption efficiency, flexibility, and stability. This enhanced performance can be attributed to the higher carboxyl content in TPCB, achieved through alkali treatment, which significantly increased the adsorption capacity of MCATPCB20. Characterization studies employing XRD, SEM, contact angle, BET, ICP‐OES, and UV measurements further supported the efficacy of MCATPCB as an effective filter system for water purification. [ABSTRACT FROM AUTHOR]

Traditionally, automated slide scanning involves capturing a rectangular grid of field‐of‐view (FoV) images which can be stitched together to create whole slide images, while the autofocusing algorithm captures a focal stack of images to determine the best in‐focus image. However, these methods can be time‐consuming due to the need for X‐, Y‐ and Z‐axis movements of the digital microscope while capturing multiple FoV images. In this paper, we propose a solution to minimise these redundancies by presenting an optimal procedure for automated slide scanning of circular membrane filters on a glass slide. We achieve this by following an optimal path in the sample plane, ensuring that only FoVs overlapping the filter membrane are captured. To capture the best in‐focus FoV image, we utilise a hill‐climbing approach that tracks the peak of the mean of Gaussian gradient of the captured FoVs images along the Z‐axis. We implemented this procedure to optimise the efficiency of the Schistoscope, an automated digital microscope developed to diagnose urogenital schistosomiasis by imaging Schistosoma haematobium eggs on 13 or 25 mm membrane filters. Our improved method reduces the automated slide scanning time by 63.18% and 72.52% for the respective filter sizes. This advancement greatly supports the practicality of the Schistoscope in large‐scale schistosomiasis monitoring and evaluation programs in endemic regions. This will save time, resources and also accelerate generation of data that is critical in achieving the targets for schistosomiasis elimination. [ABSTRACT FROM AUTHOR]

The rapid expansion of the textile industry in Tunisia has resulted in everincreasing discharges of wastewater, making it necessary to set up treatment systems allowing i) its discharge into the environment or ii) to recycle the water in the textile plant. In this study, several unitary operations were tested in order to improve the treated water quality. Thus, the following unit operations were applied: adsorption using Natural Clay (NC) and Powdered Activated Carbon (PAC), ultrafiltration (UF) and nanofiltration (NF) individually or in synergy: UF, nanofiltration, PAC-UF, NC-UF, UF-NF et Adsorption-UF/NF. The experiments were carried out on real textile effluent containing Indigo blue dye. A threshold concentration was observed above which performance no longer increases. NF alone showed better reduction of COD (67%), color (78%), and turbidity (98%) than UF alone (26%, 48%, 95%, respectively). The coupling UF-NF showed a clear improvement in water quality in terms of color (99%) and COD (98%) with an improvement in the NF flux from 67.81 L/h.m2 to 90.62 L/h.m2. No fouling was observed for NF while it is significant during UF. The used of adsorption as pretreatment to filtration leads to an enhancement of the treatment performances with a removal of 99.9%, 99.5% and 79.5% respectively for turbidity, color and COD for NC-UF and a removal of 100%, 99.4% and 79.6% respectively for turbidity, color and COD for PAC-UF. Moreover, the addition of adsorbent controls the fouling and a constant and high flux is quickly attained and remains stable over time. The use of natural clay as adsorbent represents an economically profitable solution since it can be obtained locally and the clay used can be reused in the ceramic industry as an additive for road surfacing without the need for regeneration. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman spectroscopy (SERS) has been extensively researched in bacterial detection due to its rapid nature. However, in practical applications, signal instability can easily lead to result deviations. Particularly in quantitative detection, the uneven spatial distribution of plasmonic "hotspots" and the non-uniform distribution of samples in the substrate can affect signal intensity, resulting in unreliable detection. The quantitative process is complex and challenging. To address this issue, this study proposes a novel strategy for bacterial detection that combines SERS with colorimetry. The method involves labeling bacteria using 4-MPBA@AuNPs. The labeled samples are qualitatively detected through SERS by being dropped onto a PTFE filter membrane and quantitatively analyzed through colorimetry by adding a NaCl solution. Four typical bacterial strains are chosen to validate the integrated method. The findings demonstrate its efficacy in facilitating qualitative bacterial analysis within the range of 101–108 CFU mL−1. Moreover, the method allows for preliminary concentration quantification, achieving precise detection within the 104–108 CFU mL−1 range. The innovative aspect of this study lies in the development of a novel synergistic detection strategy, integrating SERS qualitative analysis with colorimetric quantitative analysis. This approach maximizes the advantages of both techniques by enabling simultaneous qualitative and quantitative detection of bacteria on a universal substrate. It enhances the operational efficiency and result reliability of bacterial detection in real-world applications while retaining its inherent speed. [ABSTRACT FROM AUTHOR]

Membrane technology has been broadly used in environmental and biological fields due to the advantages of low cost, short time, and simple operation. It can be utilized to separate metal ions, small molecules, nanomaterials, and biomolecules. In recent years, many efforts have been made to expand atomic spectrometry (AS) based on filter-assisted separation. This article reviews recent advances in filter membranes including cellulose-based membranes, octadecyl silica membranes, and liquid membranes assisted separation combined with AS. The applications of the filter-assisted procedure in AS were classified and reviewed, including the detection of trace metal ions, nanomaterials, and biomolecules. We also discuss the future perspectives of filter membrane separation by combining AS. [ABSTRACT FROM AUTHOR]

Membrane separation technology, as an important means of treating oily wastewater, is considered to be one of the most promising oil/water separation technologies. However, problems such as membrane contamination and single separation performance have also hindered its wider application. In this study, polydopamine (PDA)-Ag nanospheres were prepared by oxidant-induced dopamine polymerization and in situ reduction with silver ions, and assembled onto silanized poly(vinylidene fluoride) (PVDF) filtration membranes by a vacuum-assisted operation. The separation efficiency of the PDA–Ag@PVDF filter membrane for the dichloroethane oil-in-water emulsion was 98.8%, and the removal rate of malachite green dye in the emulsion was as high as 98%. After multiple separation/UV irradiation cycles, the flux recovery rate was greater than 98.7%. The PDA–Ag@PVDF filter membrane is a multifunctional and self-cleaning separation membrane, whose excellent properties make it promising in the field of oil/water separation. [ABSTRACT FROM AUTHOR]

The world is constantly challenged regarding managing environmental and ecological contamination due to human and industrial activities. This is because of the constant threat posed by pollution. Nowadays, membrane‐based technology is a growing field, making practically all the separation of foulant from wastewater possible. The membrane fouling resulting from the interaction between the foulant and the membrane surface presents a challenge for the technology in maintaining performance over extended periods of operation. As a result, there is a rising interest in research focusing mainly on creating patterned membrane surfaces that reduce fouling and effectively enhance the surface area. This article comprehensively overviews the most recent and cutting‐edge techniques that can be applied to modify and construct high‐performance patterned membranes suitable for ultrafiltration, microfiltration, nanofiltration, and reverse osmosis (UF, MF, NF, and RO) water purification processes. In this study, recent developments in membrane material are dissected, focusing on methods for improving surface chemistry, structure, and hydrodynamics, as well as the consequences of these characteristics on filtering performance. [ABSTRACT FROM AUTHOR]

Although filtration is one of the most common steps in sample preparation for chemical analysis, filter membrane materials can leach contaminants and/or retain some analytes in the filtered solutions. In multiclass, multiresidue analysis of veterinary drugs, it is challenging to find one type of filter membrane that does not retain at least some of the analytes before injection in ultrahigh‐performance liquid chromatography‐tandem mass spectrometry (UHPLC‐MS/MS). In this study, different filter membranes were tested for use in UHPLC‐MS/MS analysis of 183 diverse drugs in bovine muscle, kidney, and liver tissues. Membranes evaluated consisted of polytetrafluoroethylene (PTFE), polyvinylidene difluoride (PVDF), polyethersulfone, nylon, and regenerated cellulose. Drug classes represented among the analytes included β‐agonists, β‐lactams, anthelmintics, macrolides, tetracyclines, sulfonamides, tranquilizers, (fluoro)quinolones, anti‐inflammatories, nitroimidazoles, coccidiostats, phenicols, and others. Although the presence of a matrix helped reduce the binding of analytes on surface active sites, all of the filter types partially retained at least some of the drugs in the final extracts. In testing by flow‐injection analysis, all of the membrane filters were also observed to leach interfering components. Ultimately, filtration was avoided altogether in the final sample preparation approach known as the quick, easy, cheap, effective, rugged, safe, efficient, and robust (QuEChERSER) mega‐method, and ultracentrifugation was chosen as an alternative. [ABSTRACT FROM AUTHOR]

Herein, a new type of infrared film using single‐walled carbon nanotubes (SWNTs) is developed. The optimal sonication settings to produce SWNTs with the highest possible absorption of infrared light are discovered. A hybrid infrared modulator that combines SWNTs with ionic liquids, with a very fast response time is also developed. By carefully controlling the size of the SWNT bundles and the pore size of the filter membrane used to deposit the SWNTs, a response time of a few hundred microseconds (635 μs) at the half‐power point is achieved, which is the optical 3‐dB point. This technology has the potential to be used in a variety of innovative applications, such as smart windows and military camouflage, due to its excellent infrared optical properties. [ABSTRACT FROM AUTHOR]

Herein, a novel technology named coaxial electro‐spraying/electrospinning was successfully introduced, which can simultaneously prepare nanofibers and nanoparticles. First, the device contains an outer nozzle and an inner nozzle, which combine electrospinning with electro‐spraying technology. Then, the polyamide 6 (PA6) was spun to prepare the nanofibers from the inner nozzle, and the silver nanoparticles (Ag NPs) into the PA6 solution were sprayed to prepare the nanoparticles from the outer nozzle. PA6 nanofibers (NFs)/Ag nanoparticles (NPs) antibacterial composite membranes for the filtration of fine particulate pollutants were successfully prepared using coaxial electro‐spraying/electrospinning. The microstructure, physical properties, and antibacterial properties of the composite membrane were investigated. The results show that Ag NPs are successfully loaded in situ onto PA6 NFs of approximately 100 nm to form a three‐dimensional (3D) structure. The filtration efficiency of the 3D structured filtration membrane reaches 90.98%, compared to only 12.78% for the melt‐blown cloth mask filter material when tested with polystyrene microspheres (PS) of 200 nm. The contact angle of the composite membrane decreased from 145.47° to 44.11°, indicating a significant improvement in the hydrophilicity of the membrane. Furthermore, depositing Ag on the surface fibers resulted in an impressive antibacterial rate of 99.75% against Penicillium. [ABSTRACT FROM AUTHOR]

Rapid social and industrial development has resulted in an increasing demand for fossil fuel energy, which increases particulate matter (PM) pollution. In this study, we employed a simple one-step electrospinning technique to fabricate polysulfone (PSF) fiber membranes for PM filtration. A 0.3 g/mL polymer solution with an N,N-dimethylformamide:tetrahydrofuran volume ratio of 3:1 yielded uniform and bead-free PSF fibers with a diameter of approximately 1.17 μm. The PSF fiber membrane exhibited excellent hydrophobicity and mechanical properties, including a tensile strength of 1.14 MPa and an elongation at break of 116.6%. Finally, the PM filtration performance of the PSF fiber membrane was evaluated. The filtration efficiencies of the membrane for PM2.5 and PM1.0 were approximately 99.6% and 99.2%, respectively. The pressure drops were 65.0 and 65.2 Pa, which were significantly lower than those of commercial air filters. Using this technique, PSF fiber membrane filters can be easily fabricated over a large area, which is promising for numerous air filtration systems. [ABSTRACT FROM AUTHOR]

Rationale: Air pollution caused by wildfire smoke is linked to adverse health outcomes, especially for people living with asthma. Objectives: To evaluate whether government rebates for high-efficiency particulate air (HEPA) filters, which reduce concentrations of smoke particles indoors, are cost effective in managing asthma and preventing exacerbations in British Columbia (BC), Canada. Methods: We used a Markov model to analyze health states for asthma control, exacerbation severity, and death over a retrospective time horizon of 5 years (2018–2022). Concentrations of wildfire smoke–derived particulate matter with an aerodynamic diameter ⩽2.5 μm (PM2.5) from the Canadian Optimized Statistical Smoke Exposure Model and relevant literature informed the model. The base-case analysis assumed continuous use of a HEPA filter. Costs and quality-adjusted life-years (QALYs) resulting from varying rebates were computed for each Health Service Delivery Area (HSDA). Measurements and Main Results: In the base-case analysis, HEPA filter use resulted in increased costs of $83.34 (SE, $1.03) and increased QALYs of 0.0011 (SE, 0.0001) per person. The average incremental cost-effectiveness ratio among BC HSDAs was $74,652/QALY (SE, $3,517), with incremental cost-effectiveness ratios ranging from $40,509 to $89,206 per QALY in HSDAs. Across the province, the intervention was projected to prevent 4,418 exacerbations requiring systemic corticosteroids, 643 emergency department visits, and 425 hospitalizations during the 5-year time horizon. A full rebate was cost effective in 1 of the 16 HSDAs across BC. The probability of cost-effectiveness ranged from 0.1% to 74.8% across HSDAs. A $100 rebate was cost effective in most HSDAs. Conclusions: The cost-effectiveness of HEPA filters in managing wildfire smoke–related asthma issues in BC varies by region. Government rebates up to two-thirds of the filter cost are generally cost effective, with a full rebate being cost effective only in Kootenay Boundary. [ABSTRACT FROM AUTHOR]

If fine and compressible particle systems need to be separated, the ground layer compaction caused by the compacting of the filter cake leads to high flow resistances. Thin‐film filtration is a suitable method to avoid the limiting effect of the filter cakes. Gas‐impermeable filter membranes prevent shrinkage cracking, which can occur during demoisturing of the filter cakes. Titanium dioxide and baker's yeast are used as model particle systems, which are present in different concentrations and are filtered with track‐etched membranes in different particle‐to‐pore size ratios. The parameters determined during the investigation are the residual moisture, the specific solid mass, and the completeness of the discharge. Filtration causes progressive blocking of the membrane pores, resulting in filter medium resistances that are increased by up to a factor of 175. Metabolism of yeast can cause bubbles to accumulate on the membrane and decreasing the free filter area. Without regeneration the specific solid mass flow rate is reduced by 61 % for titanium dioxide and by 13 % for yeast under ideal conditions of this experimental study. [ABSTRACT FROM AUTHOR]

Background: Of all ultraviolet (UV) radiations reaching the earth, UVA1 rays have a higher potential of penetrating and producing clinically harmful consequences. While UV radiations up to 370 nm are well‐blocked by current sunscreens, a photoprotection gap remains for the UVA1 wavelengths between 370 and 400 nm. Objective: This study was to assess under outdoor summer conditions the impact on pigmentation and skin ageing signs of a protection against UVA1 using methoxypropylamino cyclohexenylidene ethoxyethylcyanoacetate (MCE) filter added to a reference SPF50 sunscreen, in comparison with the same sunscreen without the MCE filter. Materials and Methods: This prospective randomized comparative intra‐individual study was conducted in 113 women in Brazil and China. Subjects had their face and two forearms exposed twice‐daily to a 1‐h outdoor sunlight exposure over 8 weeks. Before exposure, the SPF50 sunscreen containing 3% MCE was applied on one half‐face and one forearm and the same reference product without MCE on the other half‐face and forearm. Primary study endpoint was skin colour changes (chromametry). Other endpoints included expert panel grading of pigmentation and facial skin ageing, and naïve panel assessment of facial skin radiance and homogeneity. Results: After 8 weeks, the skin was darker on both forearms but the increase in sun‐induced pigmentation was smaller with the SPF50/MCE sunscreen. Expert panel evaluations showed no change in severity scores for pigmentation and a decreased severity scores for facial skin ageing in areas protected with the SPF50/MCE product: severity scores in areas protected with the SPF50 alone were either increased (pigmentation) or unchanged (skin ageing). Naïve panel evaluations of skin radiance and homogeneity showed statistically significant superiority of the SPF50/MCE product. Conclusion: Overall, this study demonstrates that a protection with the SPF50/MCE sunscreen significantly reduces pigmentation and ageing signs compared to the same SPF50 sunscreen. [ABSTRACT FROM AUTHOR]

With the increasing development of low-permeability reservoirs, the significance of conformance control treatment has risen considerably. To address the conflict between injectability and plugging performance, as well as to enhance the deep migration capacity of conformance control agents, preformed submicron crosslinked polymer coils (SCPCs) have been manufactured using aqueous solution dispersion polymerization. Fourier transform infrared and scanning electron microscopy were employed to examine the chemical structure and micromorphology, while particle size distribution, zeta potential, rheological, and filtration properties were analyzed. The effectiveness of conformance control was confirmed through the parallel core displacement. The effective particle size of SCPCs was at a submicron level (500~800 nm). SCPCs exhibit a transitional threshold concentration between gel and sol states (0.25 wt%~0.5 wt%). SCPCs can efficiently block the 1.2 μm microporous filter membrane. The filtration time is up to 67.8 min. SCPCs can improve the water absorption rate of lower permeability cores from 21.21% to 57.89% with a permeability difference of 5. Therefore, SCPCs have good injectability, plugging performance, and deep migration capacity and can be used for conformance control in low-permeability reservoirs. [ABSTRACT FROM AUTHOR]

Transmission of an airborne disease can occur when an individual exhales respiratory particles that contain infectious pathogens. Surgical face masks are often used to reduce the amount of respiratory aerosol emitted into the environment by an individual while also lowering the concentration of particles the individual inhales. Respiratory aerosol generation is activity-dependent with high person-to-person variability. Moreover, mask fit differs among people. Here, we measure the efficacy of surgical masks (EN14683 Type IIR) in reducing both aerosol (0.3 − 20 µm diameter) and droplet (20 − 1000 µm diameter) emission during breathing, speaking and five speech and language therapy tasks performed by a human cohort. When participants wore a surgical face mask, measured particle number concentrations at the front of the mask were always lower than that for breathing without mitigation in place. For breathing and speaking, the through-mask filtration efficiencies were 80% and 87%, respectively, while for voice therapy tasks the through-mask filtration efficiencies ranged from 89% ("Hey!") to 95% (/a::/). Size-dependent through-mask filtration efficiencies were high (80 – 95%) for particles 0.5 − 2 µm diameter, with masks filtering a greater fraction of larger particle sizes. For particle sizes >4 µm diameter, filtration efficiencies of surgical face masks for all tested respiratory tasks were ∼100%. Surgical face masks significantly reduced the number of particles emitted from all respiratory activities. These results have implications for developing effective mitigations for disease transmission through inhalation. [ABSTRACT FROM AUTHOR]

Bio-based polymers and their derivatives are promising green alternatives to petroleum-based polymers in the preparation of membranes. In this study, we developed microfiltration membranes based on acetylated cellulose ether (ACE), a high-molecular-weight cellulose-derived biopolymer, using vapor-induced phase separation. The properties of these membranes were analyzed and compared with those of a commercial cellulose acetate (CA) membrane. The pore sizes and pore distributions of the ACE membranes were controlled by the polyethylene glycol additives used in the preparation of the membranes. The ACE membranes with pore sizes of 0.20–0.53 μm were effective in removing Escherichia coli bacteria, demonstrating their viability in sterilization applications. The ACE membrane also exhibited high pure water permeance values (25,000 L m−2 h−1 bar−1) and lower non-specific protein binding compared to those of the commercial CA membrane. We believe that our study findings will promote the use of bio-based ACE membranes in commercial applications. [ABSTRACT FROM AUTHOR]

The emergence of facial masks as a critical health intervention to prevent the spread of airborne disease and protect from occupational nanomaterial exposure highlights the need for fundamental insights into the interaction of nanoparticles (<200 nm) with modern polymeric mask filter materials. While most research focuses on the filtration efficiency of airborne particles by facial masks based on pore sizes, pressure drop, or humidity, only a few studies focus on the importance of aerosol surface charge versus filter surface charge and their role in the net particle filtration efficiency of mask filters. In this study, experiments were conducted to assess mask filter filtration efficiency using positively and negatively charged polystyrene particles (150 nm) as challenge aerosols at varying humidity levels. Commercial masks with surface potential (Ψf) in the range of −10 V to −800 V were measured by an electrostatic voltmeter and used for testing. Results show that the mask filtration efficiency is highly dependent on the mask surface potential as well as the charge on the challenge aerosol, ranging from 60% to 98%. Eliminating the surface charge results in a maximum 43% decrease in filtration efficiency, emphasizing the importance of electrostatic charge interactions during the particle capture process. Moreover, increased humidity can decrease the surface charge on filters, thereby decreasing the mask filtration efficiency. The knowledge gained from this study provides insight into the critical role of electrostatic attraction in nanoparticle capture mechanisms and benefits future occupational and environmental health studies. [ABSTRACT FROM AUTHOR]

This study aimed to investigate new green methods based on combined ultrasound- and enzyme-assisted technologies to isolate bioactive peptides from Cladophora vagabunda green macroalga. Also, their antioxidant and antiproliferative activity was analysed in view of biomedical applications. Algal powder was sonicated in alkaline buffer, pH 8, at 37 °C, for 1 h. The extract was treated with proteinase K and alcalase, respectively, to obtain two protein hydrolysates. Each hydrolysate was fractionated by centrifugal ultrafiltration using filter membranes with molecular weight cut-off (MWCO) at 3 kDa, to separate small peptides. The fractions were analyzed for Trolox Equivalent Antioxidant Capacity (TEAC). The results showed higher capacity of hydrolysates obtained by alcalase treatment to scavenge free radicals. Additionally, the antiproliferative activity was evaluated in HT-29 tumor cells cultivated in the presence of peptides obtained by alcalase treatment and the results showed a decrease of cell viability below 70% after 48 h of cultivation. In conclusion, peptide fractions isolated by green techniques from C. vagabunda alga had significant biological activity and are recommended for further testing as therapeutic agents. [ABSTRACT FROM AUTHOR]

Purpose: the article presents the result of an attempt to assess the possibility of using scanning electron microscopy and energy dispersive spectroscopy (SEM/EDS) to identify silica nanoparticles (SiO2), which, due to the size of individual particles (200 nm), can be used as coronavirus markers in simulation tests. Methodology: SEM/EDS evaluation was performed using three different media types; namely membrane filters, sponge filters and graphite discs. Result: SEM/EDS studies, consisting in determining the morphology and grain size of SiO2 markers and X-ray microanalysis of their elemental composition, proved that this technique can be successfully used to identify markers. Originality: due to their particle size, ease of handling with various types of surfaces, and biological and physicochemical neutrality, silica markers can act as coronavirus substitutes in experimental studies. [ABSTRACT FROM AUTHOR]

Microplastics are an emerging and persistent form of environmental contaminants, and they have been detected in a variety of environments. Most researchers have focused on microplastics in marine environments, but there are relatively fewer studies on farmland soil ecosystems. Therefore, the aim of this study was to investigate feasible and effective methods for the identification and quantification of microplastics in farmland soil using pyrolysis-gas chromatography mass spectrometry (Pyr-GC-MS). In this work, we report on the application of density flotation, filter membranes, and digestion for effective separation and preconcentration of microplastics in soil samples. Subsequently, we optimised the density separation approach according to the number of flotations and the density of the flotation solution. The results showed that flotation twice with NaCl solution and once with ZnCl2 solution achieved a high recovery rate of microplastics at the lowest cost. A recovery percentage of 77.30–94.87% was achieved. The precision of the recovery expressed as the relative standard deviation (RSD) of the peak area was 5.05% for polyethylene (PE) microplastics, 1.71% for polypropylene (PP) microplastics, and 0.78% for polystyrene (PS) microplastics. The above data indicated that the proposed method showed excellent reproducibility and high sensitivity. Among the samples, the main component was PE (60%), followed by PP (20%) and PS (20%). The average concentrations of PE, PP, and PS microplastics in the soil were 685.55, 1069.98, and 864.23 μg/g, respectively. Based on these results, we conclude that our method has the potential for application in routine analyses. [ABSTRACT FROM AUTHOR]

Pectin, which is made from citrus peel and waste, is one of the most commonly used compounds in the food industry. For large-scale production, a combination of membrane-vacuum filtering has been suggested as an alternative to traditional methods of purifying the acidic solution for pectin extraction. This study investigates the main factors involved in the membrane filtering system for the separation of fibrous materials from an acidic pectin solution under vacuum. These factors include filter aid particle size, the amount of filter aid (perlite) added to the solution, and the vacuum level. They affect separation quality, volumetric flow rate, and energy consumption. A vacuum separation device was developed for this purpose to separate the fibrous material dissolved in the solution. The independent variables were examined at three levels, and the data were analyzed. The optimum value for each variable was determined using the response surface method (RSM). Results revealed that increasing the vacuum level from 0.2 to 0.4 bar increases the flow rate 6.5-fold, while further increase in the vacuum level decreases the flow rate. This indicates clogging of the paper filter and decreased flow rate at a vacuum level of 0.6 bar and perlite particle size of 100 microns. The evaluation results showed that the thickness of the perlite layer has the greatest effect on the separation efficiency. When increased from 1 to 2 cm, it increases the efficiency 2.5-fold. The maximum value of separation efficiency was obtained at a vacuum level of 0.2 bar, a particle size of 20 microns, and a perlite thickness of 2 cm. The energy consumption of 60-micron perlite was 0.74 Wh in the optimal state, while the larger and smaller sizes of perlite had 4.5 times the energy consumption. These findings are applicable in the industrial-scale implementation of a biomaterial separation system using vacuum membrane filtering. [ABSTRACT FROM AUTHOR]

During the consolidation period of vacuum preloading drainage of dredged mud slurry, the clogging behaviors of the filter drainage structural layers and the core boards of prefabricated vertical drains (PVD) determine the drainage capacities of PVD. However, currently, there is a lack of comprehensive research on the evaluation criteria for these two clogging behaviors. Therefore, based on typical dredged mud slurry, typical geomembranes, and raw material core boards with different bending forms, relevant macro and micro-scale experimental studies have been carried out in this study. The research results show that (1) with the application of the gradient ratio test method, the clogging behaviors of filter membranes of PVD under graded vacuum preloading can be effectively simulated. Also, in the design of graded vacuum preloading, characteristics of equivalent pore sizes and pore structures should be emphasized to investigate the suitability of filtration and drainage performance of PVD filter membranes. (2) The compressive yield strength of core board grooves is a key factor influencing the reduction rate of flow capacity. The reduction rate of flow capacity and well resistance increment can be used as comprehensive indicators reflecting the clogging behaviors of core boards, while the bending angles and bending rates of core boards can be used as specific technical indicators. (3) The proposed clogging evaluation criteria for PVD are as follows: a filter membrane gradient ratio (GR) > 4.0, a core board bending rate >60% and a core board bending angle < 45°, or a reduction rate of flow capacity of bending drainage board > 90% or well-resistance increment > 9. Also, these criteria can be incorporated into the control indicators for drainage performance of PVD used in such types of foundations. [ABSTRACT FROM AUTHOR]

A novel, simple, and rapid method is demonstrated for measuring the pore size and pore size distribution of filtration membranes (FMs) used in aqueous applications with fluorescence probes. Because the selected fluorescent probes are mixable and have strong signals, combined with the operation of dead-end filtration, this method only requires small amounts of reagents; additionally, it is time-efficient by avoiding multiple rounds of filtration. This method detects the size of a FM pore throat (i.e., the narrowest position of a pore tunnel), which is more consistent with the actual filtration situation. The conditions, such as probe concentration, temperature, transmembrane pressure difference, and types of surfactants, have been optimized. The experimental results show that the fluorescence probe method has good accuracy and reproducibility for measuring the pore size and pore size distribution of both organic and inorganic FMs. The method is particularly suitable for rapid testing of the filtration performance (nominal pore size≥0.02 μm) of purchased or synthetic membranes in the laboratory. [ABSTRACT FROM AUTHOR]

The Member States of the European Union pledged to reduce greenhouse gas emissions by 80–95% by 2050. Shallow geothermal systems might substantially contribute by providing heating and cooling in a sustainable way through seasonally storing heat and cold in the shallow ground (<200 m). When the minimum yield associated with the installation of a cost-effective aquifer thermal energy storage (ATES) system cannot be met, borehole thermal energy storage, relying mostly on the thermal conductivity of the ground, is proposed. However, for large-scale applications, this requires the installation of hundreds of boreholes, which entails a large cost and high disturbance of the underground. In such cases, ATES systems can nevertheless become interesting. This paper presents a case study performed on a Ghent University campus (Belgium), where the feasibility of ATES in an area with a low transmissivity was determined. The maximum yield of the aquifer was estimated at 5 m3/h through pumping tests. Although this low yield was attributed to the fine grain size of the aquifer, membrane filtering index tests and long-term injection tests revealed that the clogging risk was limited. A groundwater model was used to optimize the well placement. It was shown that a well arrangement in a checkerboard pattern was most effective to optimize the hydraulic efficiency while maintaining the thermal recovery efficiency of the ATES system. Hence, for large-scale projects, efficient thermal energy storage can also be achieved using a (more cost-effective) ATES system even in low-permeability sediments. [ABSTRACT FROM AUTHOR]

Environmental DNA (eDNA) is a powerful technique for the non-invasive and comprehensive monitoring of entire ecosystems. Despite its many advantages, the use of eDNA in South Africa as an assessment tool for fish biodiversity is largely underutilised. This study was performed as an initial screening to assess the efficiency of the eDNA method for characterising fish communities in South African waters using the metabarcoding approach. Water samples were collected from eight estuaries and vacuum filtered using 0.45 μm nylon membrane filters. DNA was extracted from the filters, and sample extracts underwent PCR assaying using MiFish primers for the 12S rRNA gene, prior to being sequenced on the Illumina MiSeq platform. The resulting sequence data produced 1 574 092 raw reads, which resulted in 119 operational taxonomic units (OTUs) after filtering and clustering. Taxonomic assignment of the OTUs produced four different taxonomic groups and one group representing unidentified sequences. The group with the highest number of OTUs (54%) was assigned to fish taxa consisting of 12 families and 22 genera identified across all estuaries, with only 16 taxa identified to species level. As this was a preliminary study, few samples were collected, and therefore several recommendations for a more comprehensive study design are provided. Overall, these results support the hypothesis that the eDNA metabarcoding approach can efficiently detect fish species in South African estuarine environments. [ABSTRACT FROM AUTHOR]

Membrane fractionation with track-etched membranes was used to size-profile the microelement composition of water-extractable soil colloids (WESCs). The aim of the study is the element composition of narrow WESC fractions of typical chernozems in the range of 0.01–10 µm. Micro-/ultrafiltration through a cascade of track-etched polycarbonate membrane filters with pore sizes of 5, 2, 1, 0.8, 0.4, 0.2, 0.1, 0.05, 0.03, and 0.01 µm at room temperature was used. ICP–AES using direct spraying of obtained fractions without decomposition was used; Al, Ba, Cd, Cr, Cu, Fe, Mn, Si, Sr, Ti, Zn, Ca, K, Mg, Na, P, and S were found. Narrow WESC fractions differ significantly. For macro- and microelements, maximum amounts of Si, Al, Fe, and Ti and their maximum percentages are observed in fractions with sizes above 1 µm, while Ca, Mg, Mn, Cu, Zn, K, and S are accumulated more in fractions with sizes below 1 µm. The developed approach provides preparative isolation of a detailed set of narrow WESC fractions in the micrometer–nanometer range. This provides element soil profiles that reveal distinct differences and the individual character of each fraction as well as trends in changes in the mineral matrix and microelement composition with fraction size. [ABSTRACT FROM AUTHOR]

In this study, we aimed to develop a novel method to quantify residual colorants in the water supply using a spectrocolorimeter. Cross-tests of color and turbidity showed that standard color solutions of 1–50 color units had a turbidity of ˂0.094 nephelometric turbidity unit (NTU) and turbidity standard solutions of 0.1–5 NTU had color measurements of 0 true color unit, indicating limitations in measuring colorants using conventional methods. Therefore, the samples were diluted stepwise to 1 L and filtered through a 0.45 μm cellulose membrane; then, the residuals colorants were measured using membrane filter colorimetry (MFC) with a spectrocolorimeter to determine the color difference. The color difference exhibited a high correlation with turbidity. Furthermore, scanning electron microscopy/energy-dispersive X-ray spectroscopy and inductively coupled plasma-optical emission spectrometry analyses of the same samples confirmed that the main components of the colorants were iron and manganese; the concentration of these substances in the samples was measured using MFC with the standards Fe2O3·H2O and MnO2. The results confirmed a high correlation between the color difference (△E*ab) and concentration of the samples and standard substances. Our findings suggest that MFC is a promising approach for measuring colorants in drinking water. [ABSTRACT FROM AUTHOR]

• Single-step fabrication of copper-LIG composite electrodes and filters. • Disinfection performance with bacteria and enteric virus. • The best electrochemical activity of Cu-LIG with 1% of Cu NPs. • Optimizing Cu-LIG disinfection performance with or without potential. • Application Cu-LIG membrane filters for water purification. Waterborne pathogens pose a lifelong threat, necessitating advanced disinfection systems with state-of-the-art materials. Laser-Induced Graphene (LIG), a 3-dimensional form of graphene, is a widely known electrode material for its electrically-induced antimicrobial properties. However, LIG surfaces exhibit antimicrobial properties exclusively in the presence of electricity. In this work, copper-doped LIG (Cu-LIG) composite electrodes and filters were developed with enhanced antimicrobial properties in single-step laser scribing. The work emphasizes the optimization of copper doping with LIG for both electrical and non-electrical-based disinfection. The copper doping was optimized to a minimal concentration (∼1%) just to enhance the electrochemical properties of LIG. Furthermore, the excess addition of copper was helpful towards non-electricity-based treatment without significant leaching. The prepared surfaces were tested in both electrodes and filter configuration and showed excellent antibacterial and antiviral activity against mixed bacterial culture and a model enteric virus, MS2 bacteriophage. On the application of 2.5 V with Cu-LIG electrodes, 6-log removal of bacteria and virus was achieved. Furthermore, the membrane-based electroconductive filters were tested in a flow-through configuration and demonstrated 6-log removal at 2.5 V with a flux of ∼ 500 (L·m2)/h with both bacteria and viruses at minimum energy expense. Additionally, reactive oxygen species scavenging and hydrogen peroxide generation experiments have confirmed the role of electrical effects and indirect oxidation on the inactivation mechanism. The prepared Cu-LIG composite surfaces showed potential for environmental remediation applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The experiment was to establish an analytical method for the simultaneous determination of 20 kinds of mycotoxins in maize straw feed by QuEChERS-UPLC-MS/MS. The samples were extracted with acetonitrile-acetic acid (95 : 5), and the supernatant was purified by anhydrous MgSO4, PSA and C18. Then an appropriate amount of supernatant was blown to dry with nitrogen. The samples were reconstituted with methanol-water-acetic acid (30 : 70 : 0.1), passed through a PTFE filter membrane, and separated on a C18 chromatographic column. Using the multiple reaction monitoring (MRM) scan mode to monitor the target compounds and the results were quantified by the external standard method. The results showed that the linear ranges of the 20 mycotoxins were good, and the correlation coefficients (R²) were greater than 0.99. The limits of detection were 0.15~3.10 µg/kg, with limits of quantification were 0.49~10.33 µg/kg. The recoveries at the three levels were within the range of 70.4%~118.3%, with relative standard deviations of 1%~10% (n=6). The study indicates that the method was easy to operate, reproducible and highly accurated and sensitive, which can be used for routine screening of mycotoxins in corn stalk feed. [ABSTRACT FROM AUTHOR]

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Lack of access to potable drinking water is a crucial problem faced by many communities globally, especially poverty-stricken rural regions and urban and peri-urban settlements. Consumption of contaminated drinking water leads to both chronic and acute health consequences, especially in the case of young children and immunocompromised individuals. The sixth UN Sustainable Development Goal (SDG) seeks to provide universal access to safe drinking water by the year 2030. Household water treatment systems (HWTSs), such as membrane filters and chlorination tablets, have been researched and proposed as solutions for water treatment in developing economies for decades because they can provide localized solutions that best fit the context of the community of intervention. Despite increased resources, funding, and effort, many HWTSs fail long-term, sustained implementation in developing economies. This study takes a holistic approach, considering factors from both the technical and operational environment to identify factors and circumstances that inhibit these treatment technologies. Results from an analysis of 30 articles show that studies predominantly focus on factors related to system design and performance (e.g., contaminant removal efficacy, system flow rate, impact of turbidity). Many studies also focus on factors surrounding user perception and behavior. Factors with lower coverage in the data set relate to operation and maintenance, financial sustainability, supply chain, and the legal and regulatory structures. These findings are situated within a holistic conceptual framework that serves as a resource for knowledge transfer and can be updated to fit a variety of contexts. [ABSTRACT FROM AUTHOR]

PURPOSE Etoposide, a topoisomerase II inhibitor used clinically to treat cancer, has been associated with severe anaphylactic infusion related adverse drug reactions (ADRs). In a previous study we identified a hydrophilic polyethersulfone filter as a possible cause of increased rates of pediatric etoposide infusion reactions. In this multidisciplinary follow-up analytical study, we aimed to assess the chemical structure of etoposide after passing through the same hydrophilic polyethersulfone filter. METHODS An etoposide 0.4 mg/mL infusion was prepared under aseptic conditions and then passed through a standard IV infusion set with an in-line filter in place. Samples were taken in triplicate using a needle-less access system to include sampling sites directly from the IV bag port and from the IV tubing both before and after the in-line filter. Samples were diluted into mobile phase, then an aliquot was injected into a high-performance liquid chromatography mass spectrometry HPLC-MS (Thermo TSQ Quantum Ultra) system coupled to a Diode Array Detector (DAD) (Thermo Dionex Ultimate 3000). Etoposide was monitored using a selected reaction monitoring scan (SRM) of 606.2/228.8 and wavelengths of 210, 220, 254, and 280 nm for 30 minutes. RESULTS No detectable differences were observed upon comparing the three samples. Based on these results, a chemical change in etoposide resulting from an in-line filter is unlikely to be the primary cause of increased rates of infusion reactions. CONCLUSION Pharmacists working in healthcare systems, observe many ADRs, but rarely have the resources necessary to investigate the potential etiology or causality. This report highlights importance of multi-disciplinary collaboration to investigate serious ADRs. [ABSTRACT FROM AUTHOR]

this study presents a method to recover the response function of a flexible latex membrane undergoing a dynamic event by volume oscillation using Double Digital Fringe Projection to measure the profile of the surface in a sequence of frames. By applying a frequency filter to the interference pattern, a moiré pattern was obtained. Optical phase retrieval from individual frames was performed using the Isotropic Quadrature Transform Algorithm. This fringe projection technique enables full-field measurements, including edges where other techniques could not perform due to shadows generated by the tilt angle. The procedure was devised as a non-contact system to retrieve the deformation function of a flexible surface, enhancing a valuable aspect of the methodology. The results demonstrate successful recovery of the membrane response function, highlighting the relevance of the method for accurate deformation measurements using a straightforward system. These outcomes provide significant value for the development of precise measurement techniques for flexible structures in engineering applications, such as soft robotics, biomedical devices, and material science. [ABSTRACT FROM AUTHOR]

Contamination of water with heavy metals as lead (Pb2+) is a relevant problematic issue. In this work, we have tested different types of dendritic materials for lead removal from water and further recovery. The systems employed are magnetic nanoparticles (MNP) modified with monocarboxylate and dendritic carboxylate ligands, and they are compared to pristine MNP and carbosilane dendrimers. They are all effective at removing Pb2+, but the key variations are in their recyclability. The usage of a filtering membrane was required for dendrimers, which was significantly degraded by the acidic media. In terms of MNP, those that were covered by dendritic molecules were clearly less damaged in acidic media. Finally, isotherm analysis revealed that Pb2+ interacts differently with unmodified and modified MNP. [ABSTRACT FROM AUTHOR]

The shortcomings encountered from the use of conventional methods of refining draw considerable attention when it comes to the processing of edible oils. The present invention to this effect is the usage of membrane technology, which stands out as a suitable alternative, as it offers significant advantages such as minimal chemical additions, low energy consumption, and the retention of nutrients and other desired components. This paper seeks to ascertain the quality of edible oil extracted by different solvents, refined via membrane filtration. Amounts of 25 mL of crude oil sample were extracted with three different solvents (n-hexane, ethanol, and n-hexane-ethanol blend) from seeds of Hildegardia barteri (Mast.) Kosterm. and were refined using a micro-filter of pore size of 0.45 µm and an ultrafiltration membrane with 50 kDa cut off before bleaching and deodorizing to obtain table oil. Proximate composition and elemental analyses were carried out on the table oil samples produced and compared with food-grade standards. Results obtained showed 0.133–0.53% moisture content, 0.04% ash, 98.90–99.67% ether extract, 0.23% carbohydrate, and elemental compositions of 51.60–55.00% C, 6.12–6.30% H, 6.21–6.28% O, 0.01–0.02% N, and 13.0–15.0% P for edible oil samples. The findings of this study indicate that edible oil produced from the seeds of H. barteri via membrane technology yields good-quality oil for commercial production, except for the need to enhance further reduction of phosphorus content. [ABSTRACT FROM AUTHOR]

A novel membrane consisting of cellulose acetate (CA) nanofibers and poly(N‐isopropylacrylamide) (PNIPAM) microparticles is successfully fabricated by simultaneous electrospinning and electrospraying. The CA/PNIPAM membrane has highly effective gravity‐driven separation performances for both oil/water mixtures and oil‐in‐water emulsions. It separates oil droplets from oil‐in‐water mixtures and oil‐water emulsions with rejection rates of 99.83% and 96%, respectively. In order to examine the contribution of PNIPAM particles, the performance of the CA/PNIPAM membrane is compared with the CA membrane. Increased hydrophilicity due to the inclusion of the PNIPAM particles between CA nanofibers results in a higher rejection ratio and superior antifouling performance. While the CA membrane becomes unusable after 10 cycles during the separation of the oil–water emulsion, the CA/PNIPAM membrane is still in good shape after 20 cycles. The self‐cleaning ability of the membrane is examined through the permeation flux below and above the lower critical solution temperature (LCST) of PNIPAM. The reversible thermo‐responsive flux variation proves that the pore sizes increase at temperatures above the LCST of PNIPAM. Moreover, when the lubricating oil–water emulsion is filtered through the membrane, the permeate changes from clear to turbid due to the nonretained oil particles as the temperature passes through the LCST. [ABSTRACT FROM AUTHOR]

Like all raw materials of plant origin, persimmon fruits are considered a material rich in carbohydrates. This subtropical plant grows almost throughout the entire territory of the Republic of Azerbaijan. Despite the widespread distribution of this plant in the republic, very few types of products are produced from it. The main reason why persimmon fruits are not used effectively from a production point of view is that they have astringent properties. Since fruit carbohydrates play an important role in eliminating the tart taste of persimmons, the study of the carbohydrate complex was considered as a basic condition. After fractionation of carbohydrates with a water-alcohol mixture, certain stresses arise in the filter residue, which consists of cellulose-lignin. These stresses are analyzed using tensors. It has been established that the size of the filter pores is about 0.005÷0.05 microns, and the volume of these pores is 0.062÷0.195 cm³/g. The clearance coefficient averaged 19.97 %. It is known that the outer layer of a plant cell consists of cellulose and other structural compounds. These substances determine the porosity of the material. The mass fraction of the final product of the fractional residue, more precisely cellulose, averaged 0.63 %. The use of the resulting filter membrane in the clarification of fruit juices has shown its usefulness in industry. It has been established that the selectivity of these membranes for various amino acids is 5÷18 %, and for minerals 1÷30 %. The lipid resistance of the membranes was high. It should be noted that cellulose has the ability to restore its structure and at the last stage acts only as a filter membrane. This explains the usefulness of the celluloselignin mixture as a membrane material. [ABSTRACT FROM AUTHOR]

The purpose of this research was to determine the isotope concentration of the actinide radioelements 238U, 232Th series, and 239Pu in biological samples (urine) using the alpha spectroscopy system. The samples were selected from the residence of high natural background radiation (HNBR) area and analyzed using chemical procedure. The separated sample was placed on a membrane filter by the sedimentation method, and it was prepared for counting with the alpha spectrometry system. The average radioactive concentrations found in these samples were as follows: 234U > 226Ra > 230Th > 228Ra > 228Th > 224Ra > 232Th > 239Pu. The average concentrations of 234U and 226Ra were much greater than the other radionuclides. [ABSTRACT FROM AUTHOR]

The accumulation of proteins in filter membranes limits the efficiency of filtering technologies for cleaning wastewater. Efforts are ongoing to coat commercial filters with different materials (such as titanium dioxide, TiO2) to reduce the fouling of the membrane. Beyond monitoring the desired effect of the retention of biomolecules, it is necessary to understand what the biophysical changes are in water-soluble proteins caused by their interaction with the new coated filter membranes, an aspect that has received little attention so far. Using spin-label electron paramagnetic resonance (EPR), aided with native fluorescence spectroscopy and dynamic light scattering (DLS), here, we report the changes in the structure and dynamics of bovine serum albumin (BSA) exposed to TiO2 (P25) nanoparticles or passing through commercial polyvinylidene fluoride (PVDF) membranes coated with the same nanoparticles. We have found that the filtering process and prolonged exposure to TiO2 nanoparticles had significant effects on different regions of BSA, and denaturation of the protein was not observed, neither with the TiO2 nanoparticles nor when passing through the TiO2-coated filter membranes. [ABSTRACT FROM AUTHOR]

Measurement of electrical potential difference (Δψ) in membrane vesicles (chromatophores) from the purple bacterium Rhodobacter sphaeroides associated with the surface of a nitrocellulose membrane filter (MF) impregnated with a phospholipid solution in decane or immersed into it in the presence of exogenous mediators and disaccharide trehalose demonstrated an increase in the amplitude and stabilization of the signal under continuous illumination. The mediators were the ascorbate/N,N,N′N′-tetramethyl-p-phenylenediamine pair and ubiquinone-0 (electron donor and acceptor, respectively). Although stabilization of photoelectric responses upon long-term continuous illumination was observed for both variants of chromatophore immobilization, only the samples immersed into the MF retained the functional activity of reaction centers (RCs) for a month when stored in the dark at room temperature, which might be due to the preservation of integrity of chromatophore proteins inside the MF pores. The stabilizing effect of the bioprotector trehalose could be related to its effect on both the RC proteins and the phospholipid bilayer membrane. The results obtained will expand current ideas on the use of semi-synthetic structures based on various intact photosynthetic systems capable of converting solar energy into its electrochemical form. [ABSTRACT FROM AUTHOR]