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The total oxidizable precursor (TOP) assay has been extensively used for detecting PFAS pollutants that do not have analytical standards. It uses hydroxyl radicals (HO•) from the heat activation of persulfate under alkaline pH to convert H-containing precursors to perfluoroalkyl carboxylates (PFCAs) for target analysis. However, the current TOP assay oxidation method does not apply to emerging PFAS because (i) many structures do not contain C-H bonds for HO• attack and (ii) the transformation products are not necessarily PFCAs. In this study, we explored the use of classic acidic persulfate digestion, which generates sulfate radicals (SO4-•), to extend the capability of the TOP assay. We examined the oxidation of Nafion-related ether sulfonates that contain C-H or -COO-, characterized the oxidation products, and quantified the F atom balance. The SO4-• oxidation greatly expanded the scope of oxidizable precursors. The transformation was initiated by decarboxylation, followed by various spontaneous steps, such as HF elimination and ester hydrolysis. We further compared the oxidation of legacy fluorotelomers using SO4-• versus HO•. The results suggest novel product distribution patterns, depending on the functional group and oxidant dose. The general trends and strategies were also validated by analyzing a mixture of 100000- or 10000-fold diluted aqueous film-forming foam (containing various fluorotelomer surfactants and organics) and a spiked Nafion precursor. Therefore, (1) the combined use of SO4-• and HO• oxidation, (2) the expanded list of standard chemicals, and (3) further elucidation of SO4-• oxidation mechanisms will provide more critical information to probe emerging PFAS pollutants.

Laccases from white-rot fungi catalyze lignin depolymerization, a critical first step to upgrading lignin to valuable biodiesel fuels and chemicals. In this study, a wildtype laccase from the basidiomycete Fomitiporia mediterranea (Fom_lac) and a variant engineered to have a carbohydrate-binding module (Fom_CBM) were studied for their ability to catalyze cleavage of β-O-4 ether and C-C bonds in phenolic and non-phenolic lignin dimers using a nanostructure-initiator mass spectrometry-based assay. Fom_lac and Fom_CBM catalyze β-O-4 ether and C-C bond breaking, with higher activity under acidic conditions (pH < 6). The potential of Fom_lac and Fom_CBM to enhance saccharification yields from untreated and ionic liquid pretreated pine was also investigated. Adding Fom_CBM to mixtures of cellulases and hemicellulases improved sugar yields by 140% on untreated pine and 32% on cholinium lysinate pretreated pine when compared to the inclusion of Fom_lac to the same mixtures. Adding either Fom_lac or Fom_CBM to mixtures of cellulases and hemicellulases effectively accelerates enzymatic hydrolysis, demonstrating its potential applications for lignocellulose valorization. We postulate that additional increases in sugar yields for the Fom_CBM enzyme mixtures were due to Fom_CBM being brought more proximal to lignin through binding to either cellulose or lignin itself.

Background: Chronic alcohol users often exhibit an increased minimum alveolar concentration (MAC) of sevoflurane, yet the specific mechanism remains unclear. It has been reported that ethanol exposure can upregulate the protein expression and enzyme activity of cytochrome P450 2E1 (CYP2E1). CYP2E1 is a key enzyme that converts 2–5% of sevoflurane into equimolar amounts of hexafluoroisopropanol (HFIP) and F−. This study aims to explore whether ethanol exposure could alter sevoflurane metabolism through CYP2E1 modulation, potentially explaining the increased MAC observed in alcohol users. Methods: Eighty adult male Sprague-Dawley (SD) rats were randomly divided into two groups and received either 50% ethanol (dose: 3 g/kg) or 0.9% saline twice daily by gavage. After 1, 2, 3, and 4 weeks of gavage, ten rats were randomly selected from each group to undergo 1-hour anesthesia with 2.3% sevoflurane. Blood samples were collected after anesthesia to measure the concentration of free HFIP using gas chromatography. Additionally, the left lobe tissue of the liver was collected for the analysis of CYP2E1 protein expression by Western blot and CYP2E1 enzyme activity by colorimetric assay. Correlations between these parameters were analyzed using Pearson's correlation. Results: In the ethanol group, CYP2E1 expression, activity, and the concentration of free HFIP were significantly higher at all time points compared to the control group (P < 0.05), except for protein expression in the first week (P > 0.05). Within-group comparisons indicated no significant changes in any of the parameters for the control group (P > 0.05). In the ethanol group, there was no difference in free HFIP concentration between the first and second weeks (P > 0.05), but a significant increase was observed in the third and fourth weeks (P < 0.01); protein expression and enzyme activity significantly varied over time, especially showing a notable increase from the first to the third and fourth weeks (P < 0.05). Correlation analysis revealed strong positive correlations between free HFIP concentration and CYP2E1 activity (r = 0.7898), free HFIP concentration and CYP2E1 expression (r = 0.8418), and CYP2E1 activity and expression (r = 0.8740), all with P < 0.001. Conclusions: Ethanol exposure increased both the expression and enzymatic activity of CYP2E1, consequently enhancing the metabolism of sevoflurane. [ABSTRACT FROM AUTHOR]

The realization of lithium‐metal (Li) batteries faces challenges due to dendritic Li deposition causing internal short‐circuit and low Coulombic efficiency. In this regard, the Li‐deposition stability largely depends on the electrolyte, which reacts with Li to form a solid electrolyte interphase (SEI) with diverse physico‐chemical properties, and dictates the interphasial kinetics. Therefore, optimizing the electrolyte for stability and performance remains pivotal. Hereof, glyme ethers are an emerging class of electrolytes, showing improved compatibility with metallic Li and enhanced stability in Li─Air and Li─Sulfur batteries. Yet, the criteria for selecting glyme solvents, particularly concerning Li deposition and dissolution processes, remain unclear. The SEI characteristics and Li deposition/dissolution processes are investigated in glyme‐ether‐based electrolytes with varying chain lengths, using lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and lithium nitrate (LiNO₃) salts under high capacity and limited electrolyte conditions. Longer glymes led to more homogeneous SEI, particularly pronounced with LiNO₃, minimizing surface roughness during stripping, and promoting compact Li deposits. Higher reductive stability, resulting in homogeneous interphasial properties, and slower kinetics due to high desolvation barrier and viscosity, underline stable Li growth in longer glymes. This study clarifies factors guiding the selection of glyme ether‐based electrolytes in Li metal batteries, offering insights for next‐generation energy storage systems. [ABSTRACT FROM AUTHOR]

Background: cultivated and wild plants are used to treat different ailments. The Astragalus genus is found in temperate and dry climates; thus, it is found in Egypt and the arab world. Astragalus caprinus has a good amount of bioactive chemicals, which may help explain its therapeutic effects in reducing the risk of consequences from disease. Method: The phytochemical investigation of the herb and roots of Astragalus caprinus L. included the analytical characterization for the petroleum ether components by GC/MS, unsaponifiable matter (unsap. fraction), and fatty acids (FAME) investigation by GLC analysis. Main flavonoids were chromatographically isolated from ethyl acetate and n-butanol extracts. In vitro antimicrobial activity has been tested against the Gram-positive bacteria Staphylococcus aureus and Streptococcus mutans for different plant extracts, the Gram-negative bacteria Pseudomonas aeruginosa and Klebsiella pneumonia, the fungus Candida albicans and Aspergillus niger, and the Escherichia coli bacterium. Metabolite cytotoxicity was examined using the MTT assay against HepG-2 (human liver carcinoma) and MCF-7 (breast carcinoma). Results: Identifying the important components of the herb and root petroleum ether extracts was achieved. Using column chromatography, luteolin, cosmosiin (apigenin-7-O-glucoside), and cynaroside (luteolin-7-O-glucoside) were separated and identified using UV, NMR, and Mass Spectroscopy. Root extracts displayed potential antimicrobial activity against most of the tested pathogens. Both extracts (herb and roots) were active against the MCF-7 cell line and HepG-2 cell line with IC50 62.5 ± 0.64 and 72.4 ± 2.3 µg/ml, and 75.9 ± 2.5 and 96.8 ± 4.2 µg/ml, respectively. Conclusion: Astragalus caprinus seems to be a promising source of bioactive compounds that could potentially aid in preventing disease complications and address common health issues in developing countries. Moreover, the various parts of this plant could be utilized as natural raw materials for producing health-boosting products that could address common health issues in developing countries. [ABSTRACT FROM AUTHOR]

This study aims to produce diisopropyl ether (DIPE) via isopropanol dehydration using cobalt-phosphate-supported natural zeolite catalysts. The catalytic activities of the zeolite/CoO and zeolite/Co(H2PO4)2 were compared. The asprepared catalysts were assessed using X-ray diffraction (XRD), scanning electron microscopy (SEM) with energydispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, and N2 adsorption-desorption. Surface acidity was determined using the gravimetric method with pyridine as the probe. The results of this study showed that natural zeolite was favorably impregnated by CoO and Co(H2PO4)2 species. The impregnation process affected the textural and acidic features of the catalysts. The zeolite/Co(H2PO4)2 catalyst with a loading of 8 mEq.g-1 exhibited the highest surface acidity of 1.827 mmol.g-1. This catalyst also promoted the highest catalytic activity towards isopropanol dehydration, with an isopropanol conversion of 66.19%, DIPE selectivity, and yield of 46.72% and 34.99%, respectively. The cobalt phosphate species promoted higher catalytic activity for isopropanol dehydration than the CoO species. This study demonstrated the potential of cobalt phosphate-supported natural zeolite catalysts for DIPE production with adequate performance. [ABSTRACT FROM AUTHOR]

Comblike polycarboxylate superplasticizers (PCs) have been widely used as construction and building materials by means of high fluidity and fine dispersibility via electrostatic repulsion and steric hindrance. The conventional PCs are usually synthesized by free radical polymerization, which limit to understand and even distort the structure-property relationship due to the random molecular structure and the broad polydispersity. In this work, polycarboxylate ether superplasticizers of acrylic acid (AA) and ethylene glycol monovinyl PEG (EPEG) with controlled structure were prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization. The resultant copolymers (denoted as EPCs) were characterized by FT-IR, 1H NMR and GPC spectroscopy. The effect of actual acid/ether (AA/EPEG) ratio on the adsorption capacity and dispersion ability of EPCs in cement paste were deeply investigated. These results demonstrate that the dispersibility of EPCs with controlled molecular weights and comparatively narrow polydispersity indexes (PDI=1.2–1.4) strongly depends on the acid/ether ratio. With an increase of the feed molar ratio of AA/EPEG from 4∶1 to 8∶1 , the molecular weight and their distribution of EPCs increases accordingly. In addition, the adsorption capacity and dispersion property of EPCs to cement are densely related to the molecular structure and composition and superior to that of conventional PC analogues. A possible mechanism was proposed that EPCs can act uniformly on the surface of cement particles due to the well-defined molecular structure and well-distributed molecular weight, which is different from the conventional PCs, which will offer the fundamentals of design and synthesis for polycarboxylate superplasticizers with controlled structures. [ABSTRACT FROM AUTHOR]

Coupling by metal–carbene transfer enables the formation of several different bonds at the carbenoid site, enabling prochiral Csp3 centers that are fundamental three-dimensional substructures for medicines to be forged with increased efficiency. However, strategies using bulk chemicals are rare because of the challenge of breaking two unactivated geminal bonds. Herein, we report the reactivity of ethers to form metal–carbene intermediate by cleavage of α-Csp3–H/Csp3–O bonds, which achieve selective coupling with arylmagnesium bromides and chlorosilanes. These couplings are catalysed by cyclic (alkyl)(amino)carbene-chromium complex and enable the one-step formation of 1,n-arylsilyl alcohols and α-arylated silanes. Mechanistic studies indicate that the in-situ formed low-valent Cr might react with iodobenzene to form phenyl radical species, which abstracts the α-H atom of ether in giving α-oxy radical. The latter combines with Cr by breaking α-Csp3–O bond to afford metal–carbene intermediate, which couples with aryl Grignard and chlorosilane to form two σ-bonds. Harnessing carbenoid intermediates during organic transformations is an essential strategy for catalysis but strategies using bulk chemicals are rare due to the challenge of breaking two unactivated geminal bonds. Here, the authors report the reactivity of readily available ethers to form a metal–carbene intermediate via radical-relay bond cleavage. [ABSTRACT FROM AUTHOR]

Poly-ether-ether-ketone (PEEK) and PEEK composites are outstanding candidates for biomedical applications, such as orthopedic devices, where biocompatibility and modulus match with surrounding tissue are requisite for long-term success. The mechanical properties can be optimized by incorporating fillers such as continuous and chopped carbon fibers. While much is known about the mechanical and tribological behavior of PEEK composites, there are few articles that summarize the viability of using PEEK reinforced with carbon fibers in orthopedic implants. This paper reviews biocompatibility, tribological, and mechanical studies on PEEK and their composites with carbon fibers, notably PEEK reinforced with polyacrylonitrile (PAN)-based carbon fibers and PEEK reinforced with pitch-based carbon fibers, for application in orthopedics and total joint replacements (TJRs). The main objectives of this review are two-fold. Firstly, this paper aims to assist designers in making informed decisions on the suitability of using PEEK and PEEK composites in orthopedic applications; as it is not well understood how these materials perform on the whole in orthopedics and TJRs. Secondly, this paper aims to serve as a centralized paper in which researchers can gain information on the tribological and mechanical advancements of PEEK and PEEK composites.

Non-covalent interactions are of significance in supramolecular chemistry and biochemistry, while synthetic procedures driven by these weak interactions remain challenging and rare. Inspired by the lone pair-π interaction presence in the Z-DNA structure, a light-induced regioselective sulfonation of ethers taking advantage of the lone pair-π interaction between the oxygen of ethers and sulfonyl chlorides has been disclosed. Moreover, this strategy is also applicable to the sulfonation of aniline derivatives. Features of the methods include readily accessible starting materials, high atom-economy, green and photocatalyst-free conditions and broad functional group tolerance. Mechanism studies suggest that the lone pair-π interaction plays an important role to initiate the transformation.

Traditional Chinese medicine (TCM) has been considered, for many years, an important source of medicine to treat different diseases. As a type of TCM, Illicium simonsii Maxim (ISM) is used as an anti-inflammatory, anti-bacterial, and anti-virus. Besides, ISM is also used in the treatment of cancer. In order to evaluate the anti-hepatocellular carcinoma (HCC) activity, petroleum ether extract was prepared from part of the fruit of ISM. First, the compounds of the petroleum ether fraction of Illicium simonsii Maxim (PEIM) were identified using LC-MS/MS analysis. Next, the cell viability and morphological changes were evaluated by MTT assay and Hoechst staining. In addition, the effect of PEIM on the levels of inflammatory factors (TNF-α, IL-1β, and IL-6) was determined using the ELISA kit. Furthermore, apoptosis was evaluated by flow cytometry, and gene expression and the regulation of signaling pathways were investigated, respectively, by real-time fluorescence quantitative PCR (RT-qPCR) and western blot. Results showed that a total of 64 compounds were identified in the PEIM. Additionally, the PEIM had anti-HCC activity against HepG2 cells, in which the half maximal inhibitory concentration (IC50) was 55.03 μg·mL−1. As well, the PEIM was able to modulate the expression of TNF-α, IL-1β, and IL-6, while we also found that it induced HepG2 cell apoptosis through the activation of P53 mRNA and caspase-3 mRNA. Finally, the PEIM possibly downregulated the expression of TLR4, MyD88, p-NF-κBp65, TNF-α, IL-1β, INOS, IL-6, JAK2, STAT3, CyclinD1, CDK4, MDM2, and Bcl-2, and upregulated the expression of P53, P21, Bax, Cytochrome-C, Caspase-9, and Caspase-3 in HepG2 cells. These findings may confirm that the PEIM has possible anti-HCC effects. However, additional studies are required to fully understand the mechanisms of action of the PEIM and the signaling pathways involved in its effects. Moreover, the anti-HCC activity of the PEIM should be studied in vivo, and signaling pathways involved in its effects should be explored to develop the anti-HCC drug. [ABSTRACT FROM AUTHOR]

The hydroxypropyl chitosan (HPCH) and hydroxyethyl chitosan (HECH) are multifunctional chitosan derivatives with biocompatible and biodegradable properties. Due to their hydroxypropyl and hydroxethyl groups, they have water solubility, moisture retention, and gelling properties. In this study, the chitosan derivatives HPCH and HECH were obtained in two steps alkalisation and etherification. For alkalisation, chitosan was kept in an alkaline medium at -18C for 7 days. For etherification; the reaction was carried out for 48 hours by mixing alkaline chitosan with propylene oxide and ethylene oxide separately in a pressure reactor. The structures of the obtained HPCH and HECH were characterised by FT-IR, 1H(13C)-NMR, XRD, and TG analysis methods. Since the degree of deacetylation (DA) of chitosan is 75-85%, the chitosan units contain N-acetyl (-N-(CO)-CH3)) groups in addition to NH2 functional groups. When the 1H(13C)-NMR spectrum of chitosan was examined, the peak value of these acetyl groups was observed at δ1.89 ppm. When the XRD spectra were examined, it was observed that the strong peak in chitosan at 2θ-20° was weakened in HPCH and HECH. In addition, the thermal stability of HPCH and HECH was found to be higher than chitosan in TG analysis. [ABSTRACT FROM AUTHOR]

Three new heteroleptic Ag(I) complexes, labeled as [AgL(POP)]BF4 (1–3), were successfully synthesized and comprehensively characterized. Here, L represents 2,9-bis((E)-4-methoxystyryl)-1,10-phenanthroline (L1), 2,9-bis((E)-4-methylthiostyryl) -1,10-phenanthroline (L2), and 2,9-bis((E)-4-diethylaminostyryl)-1,10-phenanthroline (L3), while POP stands for Bis[(2-diphenylphosphino)phenyl] ether. The stability of these compounds in solution was confirmed through multinuclear 1D (1H, 13C, 31P) and 2D NMR (COSY, NOESY, HMBC, HSQC) spectroscopies. Additionally, their molecular structure was elucidated via X-ray crystallography. The photophysical properties of the complexes were assessed both in the solid state and in solution (dichloromethane). Compounds 1–3 demonstrated moderate emissions in solution, with quantum yields ranging from 11–23%. Interestingly, their solid-state luminescent behavior differed. Large bathochromic shifts (42–75 nm) of the emission maxima and a decrease in quantum yields (2.5–9.5%) were evident, possibly due to the presence of excimers. Compound 3 stands out as a rare example of an Ag(I) red-color emitter. [ABSTRACT FROM AUTHOR]

Biopolymers are biodegradable and renewable and can significantly reduce environmental impacts. For this reason, biocomposites based on a plasticized starch and cross-linker matrix and with a microfibrillated OCC cardboard cellulose reinforcement were developed. Biocomposites were prepared by suspension casting with varied amounts of microfibrillated cellulose: 0, 4, 8, and 12 wt%. Polyethylene glycol diglycidyl ether (PEGDE) was used as a cross-linking, water-soluble, and non-toxic agent. Microfibrillated cellulose (MFC) from OCC cardboard showed appropriate properties and potential for good performance as a reinforcement. In general, microfiber incorporation and matrix cross-linking increased crystallization, reduced water adsorption, and improved the physical and tensile properties of the plasticized starch. Biocomposites cross-linked with PEGDE and reinforced with 12 wt% MFC showed the best properties. The chemical and structural changes induced by the cross-linking of starch chains and MFC reinforcement were confirmed by FTIR, NMR, and XRD. Biodegradation higher than 80% was achieved for most biocomposites in 15 days of laboratory compost. [ABSTRACT FROM AUTHOR]

In this paper, sulfonic acid functionalized benzothiazole ionic liquid ([(CH2)3SO3HBth] [H2PO4]) and graphene oxide were combined together through the cation‐π. The sulfonated poly (ether ether ketone) was doped with ionic liquid‐modified GO (IL‐GO) to prepare the SPEEK/IL‐GO composite membrane through the solution casting method. The SO3H and benzothiazole rings act as both proton acceptors and proton donors during proton transport and can replace the role of water in medium‐ and high‐temperature environments, increasing the proton transport sites to a certain extent and increasing the proton conductivity of the SPEEK/IL‐GO composite membrane. The proton conductivity of the SPEEK/IL‐GO‐2 composite membrane achieved an 18.02 mS/cm at 120°C, which is 2.43 times higher than that of the pristine SPEEK membrane. This paper provided a method for increasing proton conductivity and limiting IL loss of the SPEEK membrane. Highlights: [(CH2)3SO3HBth][H2PO4] and graphene oxide were combined through cation‐π.The benzothiazole ring and SO3H form acid–base pairs.The proton conductivity of SPEEK/IL‐GO‐2 membrane achieved 18.02 mS/cm. [ABSTRACT FROM AUTHOR]

Ion mobility mass spectrometry (ESI-tims-ToF–MS, syringe pump infusion) has been applied to glucose and oligosaccharide ethers derived from hydroxyethyl-methyl celluloses (HEMC) and hydroxyethyl celluloses (HEC) after permethylation and partial depolymerization: by hydrolysis without or with subsequent reductive amination with m-amino benzoic acid (mABA) or by reductive cleavage. As model compounds without tandem substitution methoxyethylated methylcellulose was used. Regioisomeric glucose ethers were separated according to their ion mobility, and positions of substitution could be assigned. Glucose ethers including isomers with tandem substitution showed additional signals with a smaller collision cross-section (CCS) than core-substituted isomers. Positional isomers of cellobiose ethers were only partly resolved due to too high complexity but showed a characteristic fingerprint that might allow classifying samples. Relative intensities of signals of glucose ether isomers could only be quantified in case of ABA derivatives with its fixed charge, while sodium adducts of methoxyethyl ethers showed an influence of the MeOEt position on ion yield. Results were in very good agreement with reference analysis. [M + Na]+ adducts of α- and β-anomers of glucose derivatives were separated in IM, complicating position assignment. This could be overcome by reductive cleavage of the permethylated HE(M)C yielding 1,5-anhydroglucitol-terminated oligosaccharides, showing the best resolved fingerprints of the cellobiose ethers of a particular cellulose ether. With this first application of ion mobility MS to the analysis of complex cellulose ethers, the promising potential of this additional separation dimension in mass spectrometry is demonstrated and discussed. [ABSTRACT FROM AUTHOR]

In this study we develop novel type of antibacterial chitosan-propolis NPs to improve theantimicrobial activity against various pathogens. To this aim, we primarily extracted propolis with methylal and ethanol as green solvents and its encapsulation with chitosan NPs. The developed propolis loaded chitosan NPs indicated antimicrobial and anti-biofilm properties against various gram positive and negative. FTIR revealed the successful encapsulation of the propolis extract with Ethanol (PE) and Methylal (PM) into the chitosan nano career matrix. HPLC and GC-MASS also confirmed the presence of flavonoids and phenols compounds of propolis extracted with both solvents. In addition, we confirmed the total phenolic and flavonoid compounds in propolis by calorimetric method of Folin–Ciocalteu and aluminum trichloride complex formation assays, respectively. PE-CH and PM-CH were optimized regarding physicochemical properties such as particle size, zeta potential, and poly dispersity index (PDI) index. DLS and SEM micrographs confirmed a spherical morphology in a range of 360–420 nm with Z potential values of 30–48 mV and PDI of 0.105–0.166 for PE-CH and PM-CH, respectively. The encapsulation efficiency was evaluated using colorimetric analysis, with median values ranging from 90 to 92%. The MIC values within the range of 2 to 230 µg/ml and MBC values between 3 to 346 μg/ml against both gram-positive and negative bacteria. While both PE and PM showed a significant reduction in the number of E. coli, S. aureus, and S. epidermidis, the use of PE-CH and PM-CH led to a statistically significant and greater reduction in number of E. coli, S. aureus, and S. epidermidis strains on the biofilm, pre-formed biofilm and planktonic phases. Besides, the DPPH assay showed significant antioxidant activity for these NPs within the range of 36 to 92%. MTT assay for MHFB-1, HFF, L929, MDF, and MCF-7 cells exhibited statistically significant differences in each other that show the IC50 between 60–160 µg/ml for normal cells and 20 for cancer cells. Finally the present study indicated that both PM and PM-CH greater than PE and PE-CH in which contain high flavonoid and phenolic contents with a high antioxidation potential antioxidant properties, which could be beneficial for cell proliferation and antibiotic and anticancer applications. [ABSTRACT FROM AUTHOR]

Background. Dental implantation has become a standard procedure with high success rates, relying on achieving osseointegration between the implant surface and surrounding bone tissue. Polyether ether ketone (PEEK) is a promising alternative to traditional dental implant materials like titanium, but its osseointegration capabilities are limited due to its hydrophobic nature and reduced surface roughness. Objective. The aim of the study is to increase the surface roughness and hydrophilicity of PEEK by treating the surface with piranha solution and then coating the surface with epigallocatechin-3-gallate (EGCG) by electrospraying technique. Materials and Methods. The study includes four groups intended to investigate the effect of piranha treatment and EGCG coating: a control group of PEEK discs with no treatment (C), PEEK samples treated with piranha solution (P), a group of PEEK samples coated with EGCG (E), and a group of PEEK samples treated with piranha solution and coated with EGCG (PE). Surface roughness, wettability, and microhardness were assessed through statistical analysis. Results. Piranha treatment increased surface roughness, while EGCG coating moderated it, resulting in an intermediate roughness in the PE group. EGCG significantly improved wettability, as indicated by the reduced contact angle. Microhardness increased by about 20% in EGCG-coated groups compared to noncoated groups. Statistical analysis confirmed significant differences between groups in all tests. Conclusion. This study demonstrates the potential of EGCG coating to enhance the surface properties of PEEK as dental implants. The combined piranha and EGCG modification approach shows promise for improved osseointegration, although further vivo research is necessary. Surface modification techniques hold the key to optimizing biomaterial performance, bridging the gap between laboratory findings and clinical implementation in dental implantology. [ABSTRACT FROM AUTHOR]

Sunflowers are widely cultivated as a cash crop in the Inner Mongolia Autonomous Region, China. However, due to the lack of efficient resource utilization techniques, most of the sunflower stalks are discarded. In the Hetao irrigation area, the problem of desertification has prompted the limited use of sunflower straw to construct physical sand barriers for windbreaks and sand stabilization. In response to this, this study focuses on synthesizing a cellulose ether sand-fixing material using sunflower straw, the primary agricultural waste in Denkou County, Hetao irrigation district. This material enhances the effective adhesion between sand grains, reduces porosity among loose sand grains, and inhibits sand grain movement. The findings from this study conclusively demonstrate that the sand-fixing materials under investigation meet international standards for mechanical properties. They effectively transform loose, unconnected sand grains into a state with strong adhesion properties. [ABSTRACT FROM AUTHOR]

Phenazine-based redox-active centers are capable of averting chemical bond rearrangements by coupling during the reaction process, leading to enhanced stabilization of the material. When introduced into a high-performance polymer with excellent physicochemical properties, they can be endowed with electrochemical properties and related prospective applications while maintaining the capabilities of the materials. In this study, a facile C-N coupling method was chosen for the synthesis of serial poly(aryl ether sulfone) materials containing phenazine-based redox-active centers and to explore their electrochemical properties. As expected, the cyclic voltammetry curves of PAS-DPPZ-60, which basically overlap after thousands of cycles, indicate the stability of the electrochemical properties. As an electrochromic material, the transmittance change in PAS-DPPZ-60 exhibits only a slight attenuation after as long as 600 cycles. Meanwhile, as an organic battery cathode material, PAS-DPPZ has a theoretical specific capacity of 126 mAh g−1, and the capacity retention rate is 82.6% after 100 cycles at a 0.1 C current density. The perfect combination of advantageous features between phenazine and poly(aryl ether sulfone) is considered to be the reason for the favorable electrochemical performance of the material series. [ABSTRACT FROM AUTHOR]

2(C37H48N4O5), C4H10O, orthorhombic, P212121 (no. 19), a = 11.8629(3) Å, b = 23.3541(6) Å, c = 27.4519(7) Å, V = 7605.5(3) Å3, Z = 4, Rgt(F) = 0.0355, wRref(F2) = 0.0979, T = 123 K. [ABSTRACT FROM AUTHOR]

Diaryl difluoromethanes are valuable targets for medicinal chemistry because they are bioisosteres of diaryl ethers and can function as replacements for diaryl methane, ketone, and sulfone groups. However, methods to prepare diaryl difluoromethanes are scarce, especially methods starting from abundant aryl halides. We report the Pd-catalyzed aryldifluoromethylation of aryl halides with aryldifluoromethyl trimethylsilanes (TMSCF2 Ar). The reaction occurs when the catalyst contains a simple, but unusual, dialkylaryl phosphine ligand that promotes transmetallation of the silane. Computational studies show that reductive elimination following transmetallation occurs with a low barrier, despite the fluorine atoms on the α-carbon, due to coordination of the difluorobenzyl π-system to palladium. The co-development of a cobalt-catalyzed synthesis of the silanes broadened the scope of the process including several applications to the synthesis biologically relevant diaryl difluoromethanes.

Because of environmental impact, there is a great need for chemosensors, especially for toxic heavy metals such as lead. The conventional instrumental analytical techniques rarely provide an available real-time sensing platform, thus the development of highly selective and stable synthetic chemosensor molecules is of great importance. Acridono-18-crown-6 ethers have such properties, and much research has proven their outstanding applicability in various supramolecular devices. In this present work, we aimed to enable their covalent immobilization capability by synthesizing functionalized derivatives while preserving the favored molecular recognition ability. Several new macrocycle analogues were synthesized, while synthetization difficulties and design aspects were also dealt with. The selectivity of the macrocycle analogues was studied using UV–Vis spectroscopy and compared with that of the parent compounds. The ultimate crown ether derivative showed high Pb2+-selectivity, reversibility (decomplexation by extraction with water) and stability. [ABSTRACT FROM AUTHOR]

Aromatic nucleophilic substitution polymerization was used to synthesize five poly(ether nitrile imide)s (PENIs) that include benzonitrile and bulky cardo groups from a mixture of phenolphthalein (PP), 4,4′‐bis(4‐fluorophthalimide) diphenyl ether (4,4′‐BFPI), and 2,6‐difluorobenzonitrile (DFBN). The structure and properties relationship of PENIs with different ratios of DFBN and 4,4′‐BFPI was explored. It was found that the glass transition temperature (Tg) of PENIs decreased from 280 to 260°C, while the temperature of 5% thermal weight loss (T5%) in N2 increased from 429 to 453°C as the benzonitrile content in PENI increased. The produced PENI films had good mechanical characteristics, including tensile strengths of 103–112 MPa, elongations at break of 5.6%–8.2%, and tensile moduli of 2.9–3.4 GPa. Furthermore, the solubility and melt processability were also improved with the introduction of the benzonitrile group. Compared with poly(ether ketone imide)s (PEKIs) and poly(ether sulfone imide)s (PESIs), PENIs with benzonitrile displayed higher Tg, tensile modules, and lower complex viscosity. [ABSTRACT FROM AUTHOR]

20-Hydroxyecdysone and several of its oxidized derivatives exert cytoprotective effect in mammals including humans. Inspired by this bioactivity of ecdysteroids, in the current study it was our aim to prepare a set of sidechain-modified derivatives and to evaluate their potential to protect the blood-brain barrier (BBB) from oxidative stress. Six novel ecdysteroids, including an oxime and five oxime ethers, were obtained through regioselective synthesis from a sidechain-cleaved calonysterone derivative 2 and fully characterized by comprehensive NMR techniques revealing their complete 1H and 13C signal assignments. Surprisingly, several compounds sensitized hCMEC/D3 brain microvascular endothelial cells to tert-butyl hydroperoxide (tBHP)-induced oxidative damage as recorded by impedance measurements. Compound 8, containing a benzyloxime ether moiety in its sidechain, was the only one that exerted a protective effect at a higher, 10 μM concentration, while at lower (10 nM– 1 μM) concentrations it promoted tBHP-induced cellular damage. Brain endothelial cells were protected from tBHP-induced barrier integrity decrease by treatment with 10 μM of compound 8, which also mitigated the intracellular reactive oxygen species production elevated by tBHP. Based on our results, 17-oxime ethers of oxidized ecdysteroids modulate oxidative stress of the BBB in a way that may point towards unexpected toxicity. Further studies are needed to evaluate any possible risk connected to dietary ecdysteroid consumption and CNS pathologies in which BBB damage plays an important role. [ABSTRACT FROM AUTHOR]

Activated blood coagulation factor X (FXa) plays a critical initiation step of the blood-coagulation pathway and is considered a desirable target for anticoagulant drug development. It is reversibly inhibited by nonvitamin K antagonist oral anticoagulants (NOACs) such as apixaban, betrixaban, edoxaban, and rivaroxaban. Thrombosis is extremely common and is one of the leading causes of death in developed countries. In previous studies, novel thiourea and oxime ether isosteviol derivatives as FXa inhibitors were designed through a combination of QSAR studies and molecular docking. In the present contribution, molecular dynamics (MD) simulations were performed for 100 ns to assess binding structures previously predicted by docking and furnish additional information. Moreover, three thiourea- and six oxime ether-designed isosteviol analogs were then examined for their drug-like and ADMET properties. MD simulations demonstrated that four out of the nine investigated isosteviol derivatives, i.e., one thiourea and three oxime ether ISV analogs, form stable complexes with FXa. These derivatives interact with FXa in a manner similar to Food and Drug Administration (FDA)-approved drugs like edoxaban and betrixaban, indicating their potential to inhibit factor Xa activity. One of these derivatives, E24, displays favorable pharmacokinetic properties, positioning it as the most promising drug candidate. This, along with the other three derivatives, can undergo further chemical synthesis and bioassessment. [ABSTRACT FROM AUTHOR]

As a high-performance engineering plastic, polyarylene ether nitrile (PEN) is widely used in many fields. The presence of cyano groups of PEN ensures its good adhesion to other substrates, but the inherent low crystallinity of PEN limits its application. In this work, the poly(aryl ether ketone) segment was introduced into PEN via copolymerization using both 2,6-Dichlorobenzonitrile and 4,4′-Difluorobenzophenone as the starting reagents to prepare poly (ether nitrile ketone) (BP-PENK). The effect of composition and thermal treatment on the crystallization behavior and properties of poly (ether nitrile ketone) were systematically studied. It was found that when the content of DFBP is 30%, the copolymer BP-PENK30 had the best mechanical properties, with a tensile strength of 109.9 MPa and an elongation at a break value of 45.2%. After thermal treatment at 280 °C for 3 h, BP-PENK30 had the highest crystallinity with a melting point of 306.71 °C, a melting enthalpy of 5.02 J/g, and crystallinity of 11.83%. Moreover, with the increase in crystallinity, the dielectric constant and energy density increased after thermal treatment. Therefore, the introduction of poly(aryl ether ketone) chain segments and thermal treatment can effectively improve the crystallization and the comprehensive properties of PEN. [ABSTRACT FROM AUTHOR]

Study design: A retrospective study. Objective: The aim of this study was to compare clinical and radiological outcomes of the anterior cervical discectomy and fusion (ACDF) with a novel zero-profile variable-angle (Zero-P VA) spacer and a traditional poly-ether-ether-ketone (PEEK) cage and plate system in cases pertaining to cervical radiculopathy/myelopathy. Summary of background data: There are two conventional types of ACDF procedures aimed at treating symptomatic cervical spondylosis. The first one involves an uninstrumented "stand-alone" approach utilizing bone graft/cage, while the second incorporates bone graft/cage in conjunction with a front plate positioned before the vertebral bodies. Both procedures have their own inherent advantages and disadvantages. The Zero-P VA spacer, however, represents a unique synthesis by amalgamating the advantages of both traditionally typical procedures. Notably, this spacer can potentially circumvent the issue related to prevertebral soft-tissue disturbance and reduce the occurrence of dysphagia. Methods: Using our surgical database, the authors systematically conducted a retrospective analysis encompassing all patients who underwent single-level ACDF between January 2018 and January 2019, with a minimum two-year follow-up. Patients either received a Zero-P VA implant or PEEK cage coupled with plating. The Japanese Orthopedic Association (JOA) score and Visual Analogue Scale (VAS) for arm and neck pain were documented. Dysphagia was evaluated using the Eating Assessment Tool-10 (ETA-10). Additional parameters such as cervical alignment, fusion rate and the incidence of postoperative complications were assessed. Results: According to the outcomes of the statistical analysis, there was no substantial disparity that emerged in the advancements observed in the JOA and VAS metrics between the two study cohorts. Noteworthy, however, the ETA-10 scores were statistically significantly reduced in the Zero-P VA group compared to the cage and plating group (p < 0.05). At the final follow-up, there were no statistically significant differences in the height of the operated segment, Cobb angle of the fused segment, C2–C7 Cobb angle and fusion rate between the two groups (p > 0.05). However, postoperative complications were slightly lower in patients with the Zero-P VA group (7.69%) as compared to the cage and plating group (16.67%). Conclusion: The clinical outcomes observed with the Zero-P VA spacer used for single-level ACDF were found to be satisfactory. The performance of this device is comparable or even superior to the traditional cage and plating method in preventing postoperative dysphagia and mitigating potential complications associated with the use of a plate. [ABSTRACT FROM AUTHOR]

Seventeen new xanthene-1,8-dione derivatives were synthesized and evaluated as cytotoxic agents against the lung carcinoma cell line (A549). Compound 9-(4-(benzyloxy)phenyl)-3,4,5,6,7,9-hexahydro-1H-xanthene-1,8(2H)-dione (4a) showed good cytotoxic effects (34.59 μM) in comparison to cis-platin. Docking results showed 4a could interact with DNA as intercalation. Calculated ligand efficiency of compound 4a was more than daunomycin. Based on the results, it can be concluded that compound 4a is a suitable DNA binding agent. [ABSTRACT FROM AUTHOR]

Phase equilibria, interdiffusion and structure in the initial uncured mixtures of epoxy oligomer–polysulfone–alkyl glycidyl ether were studied. Binodal curves were constructed on isothermal sections of the ternary phase diagram. Thermodynamic mixing parameters were calculated and spinodal curves were plotted. The interdiffusion coefficients of components, establishing the technological modes of mixing the components, were determined. To validate the phase diagram, the phase structure of mixtures, the composition of which at a temperature of 40 °C corresponds to heterogeneous and homogeneous regions, was studied. [ABSTRACT FROM AUTHOR]

The following paper proposes a modern method of obtaining an extract from Viola tricolor L. with a high rutin content and enhanced antioxidant activity. Conventional isolation of active substances from plant raw material is high‐cost, elaborate and often harmful to the environment. The ultrasonic assistance micelle‐mediated extraction method (UAMME) and the cloud‐point extraction/separation technique are interesting alternatives. This work discusses the relationship between salt concentration and the cloud‐point extraction (CPE) yield. The molecular dynamic simulations investigated the impact of hydrocarbon chain length and the ratio of oxyethylene/oxypropylene units of model surfactants on the interactions between extraction system components. Micellar extract from the Viola tricolor was obtained using C9‐11 Pareth‐5 at 1 wt/vol% and subsequently concentrated by CPE with the addition of NaCl in concentrations from 5% to 30%. For comparison, water and ethanol extracts were also prepared. Antioxidant properties, polyphenols and flavonoid contents were measured for all samples. The HPLC method was used to determine the rutin concentration. The simulation part of the study confirmed the dependence of bioflavonoid solubilization efficiency on the surfactant structure. The determined descriptors allowed for finding the optimal structure of the model surfactants and gave a hint for their application to obtain extracts with high concentrations of antioxidants. [ABSTRACT FROM AUTHOR]

BACKGROUND: In 2015, the U.S. Consumer Product Safety Commission (CPSC) received and then, in 2017, granted a petition under the Federal Hazardous Substances Act to declare certain groups of consumer products as banned hazardous substances if they contain nonpolymeric, additive organohalogen flame retardants (OFRs). The petitioners asked the CPSC to regulate OFRs as a single chemical class with similar health effects. The CPSC later sponsored a National Academy of Sciences, Engineering, and Medicine (NASEM) report in 2019, which ultimately identified 161 OFRs and grouped them into 14 subclasses based on chemical structural similarity. In 2021, a follow-up discussion was held among a group of scientists from both inside and outside of the CPSC for current research on OFRs and to promote collaboration that could increase public awareness of CPSC work and support the class-based approach for the CPSC’s required risk assessment of OFRs. OBJECTIVES: Given the extensive data collected to date, there is a need to synthesize what is known about OFR and how class-based regulations have previously managed this information. This commentary discusses both OFR exposure and OFR toxicity and fills some gaps for OFR exposure that were not within the scope of the NASEM report. The objective of this commentary is therefore to provide an overview of the OFR research presented at SOT 2021, explore opportunities and challenges associated with OFR risk assessment, and inform CPSC’s work on an OFR class-based approach. DISCUSSION: A class-based approach for regulating OFRs can be successful. Expanding the use of read-across and the use of New Approach Methodologies (NAMs) in assessing and regulating existing chemicals was considered as a necessary part of the class-based process. Recommendations for OFR class-based risk assessment include the need to balance fire and chemical safety and to protect vulnerable populations, including children and pregnant women. The authors also suggest the CPSC should consider global, federal, and state OFR regulations. The lack of data or lack of concordance in toxicity data could present significant hurdles for some OFR subclasses. The potential for cumulative risks within or between subclasses, OFR mixtures, and metabolites common to more than one OFR all add extra complexity for class-based risk assessment. This commentary discusses scientific and regulatory challenges for a class-based approach suggested by NASEM. This commentary is offered as a resource for anyone performing class-based assessments and to provide potential collaboration opportunities for OFR stakeholders. [ABSTRACT FROM AUTHOR]

Asymmetric ethers such as Cyclopentyl Methyl Ether (CPME) found their application as alternative solvents in technology; they are often labeled as "green solvents" as they can be prepared using renewable feedstock. They are almost immiscible with water and can be easily regenerated. Based on earlier experiments with CPME preparation in laboratory conditions and the estimated product yields, an initial assessment of the reaction mixture separation train was performed, for the chosen production capacity of 100 kg·h−1 of CPME. Following suitable thermodynamic model selection, basic analyses in Aspen Plus software were executed. Reactor effluent containing eight chemical species was subjected to multiple separation steps including extraction and several rectifications including one vapor phase compression step to yield saleable products with sufficient purity and unreacted chemicals recyclable to the reactor. Basic simulations were performed to find the optimal working conditions of individual columns and to estimate the associated energy needs. Basic design, without any heat or work integration measures, required a total heating duty of 787 kW and a total cooling duty of 614 kW. This yielded a specific heat consumption of 28.3 GJ per ton of the main product (CPME) which is unacceptably high as it represents around 70% of its chemical energy content (heating value). Further research will be devoted to reducing heating and cooling duty by integrated separation train design development to comply with the reduced carbon footprint mandatory for the syntheses and separations of green solvents. [ABSTRACT FROM AUTHOR]

INTRODUCTION 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), a metabolite of tobacco-specific nitrosamine (TSNA) 4-(methylnitrosamino)-1-(3-pyridyl)-1- butanone (NNK), is a tobacco-specific carcinogen. Spirometry values (FEV1%, PEF%, etc.) are commonly used as clinical indicators to assess the condition of lung function and the results can be used to diagnose respiratory diseases. However, the relationship between urinary NNAL levels and lung function is unclear. METHODS We performed a secondary dataset analysis of the three cycles of the National Health and Nutrition Examination Survey (NHANES) from 2007 to 2012. The association of urinary NNAL with spirometry values was assessed using weighted linear models. In addition, subgroup analyses by gender were also tested. RESULTS One unit increased in urinary NNAL could result in a 28% decrease of FEV1/FVC% (mean difference, MD= -0.28; 95% CI: -0.39 -- -0.17), 44% decrease of FEV1% (MD= -0.44; 95% CI: -0.69 -- -0.18), and FEV1/FEV6% and FEV3/FEV6% decreased by 20% and 8%, respectively. Increased urinary NNAL was associated with lower PEF% (MD= -0.85; 95% CI: -1.19 -- -0.51), FEF25-75% (MD= -1.40; 95% CI: -1.94 -- -0.87), and FENO (MD= -0.67; 95% CI: -0.92 -- -0.42). But forced expiratory time (FET) showed an increment (MD=0.10; 95% CI: 0.03-0.16). The FEV1/FEV6% and FEV3/FEV6% showed decreasing trend from the lowest urinary NNAL quartiles to the highest urinary NNAL quartiles, while FET showed an increased trend. PEF%, FEF 25-75%, and FENO showed the same decreasing trend (all p<0.05). In addition, urinary NNAL seemed to affect spirometry values more in males. CONCLUSIONS Urinary NNAL was negatively correlated with FEV1/FVC%, FEV1%, FEV1/FEV6%, FEV3/FEV6%, PEF%, FEF25-75%, and FENO, which was closely related to lung function. [ABSTRACT FROM AUTHOR]

Selective oxidative C–O coupling of hydrazones with diacetyliminoxyl is demonstrated, in which diacetyliminoxyl plays a dual role. It is an oxidant (hydrogen atom acceptor) and an O-partner for the oxidative coupling. The reaction is completed within 15–30 min at room temperature, is compatible with a broad scope of hydrazones, provides high yields in most cases, and requires no additives, which makes it robust and practical. The proposed reaction leads to the novel structural family of azo compounds, azo oxime ethers, which were discovered to be highly potent fungicides against a broad spectrum of phytopathogenic fungi (Venturia inaequalis, Rhizoctonia solani, Fusarium oxysporum, Fusarium moniliforme, Bipolaris sorokiniana, Sclerotinia sclerotiorum). [ABSTRACT FROM AUTHOR]

Confronting the pressing challenge of freshwater scarcity, polymeric membrane-based water treatment technology has emerged as an essential and effective approach. Poly(arylene ether)s (PAEs) polymers, a class of high-performance engineering thermoplastics, have garnered attention in recent decades as promising membrane materials for advanced water treatment approaches. The PAE-Based membranes are employed to resist the shortages of most common polymeric membranes, such as chemical instability, structural damage, membrane fouling, and shortened lifespan when deployed in harsh environments, owing to their excellent comprehensive performance. This article presents the advancements in the research of several typical PAEs, including poly(ether ether ketone) (PEEK), polyethersulfone (PES), and poly(arylene ether nitrile) (PEN). Techniques for membrane formation, modification strategies, and applications in water treatment have been reviewed. The applications encompass processes for oil/water separation, desalination, and wastewater treatment, which involve the removal of heavy metal ions, dyes, oils, and other organic pollutants. The commendable performance of these membranes has been summarized in terms of corrosion resistance, high-temperature resistance, anti-fouling properties, and durability in challenging environments. In addition, several recommendations for further research aimed at developing efficient and robust PAE-based membranes are proposed. [ABSTRACT FROM AUTHOR]

The present review explores the critical role of oxime and oxime ether moieties in enhancing the physicochemical and anticancer properties of structurally diverse molecular frameworks. Specific examples are carefully selected to illustrate the distinct contributions of these functional groups to general strategies for molecular design, modulation of biological activities, computational modeling, and structure–activity relationship studies. An extensive literature search was conducted across three databases, including PubMed, Google Scholar, and Scifinder, enabling us to create one of the most comprehensive overviews of how oximes and oxime ethers impact antitumor activities within a wide range of structural frameworks. This search focused on various combinations of keywords or their synonyms, related to the anticancer activity of oximes and oxime ethers, structure–activity relationships, mechanism of action, as well as molecular dynamics and docking studies. Each article was evaluated based on its scientific merit and the depth of the study, resulting in 268 cited references and more than 336 illustrative chemical structures carefully selected to support this analysis. As many previous reviews focus on one subclass of this extensive family of compounds, this report represents one of the rare and fully comprehensive assessments of the anticancer potential of this group of molecules across diverse molecular scaffolds. [ABSTRACT FROM AUTHOR]

The present study deals with the effect of Multiwall Carbon Nanotube (MWCNT) and its functionalized (carboxyl and amine) MWCNT on the mechanical properties of Poly Aryl Ether Ketone (PAEK) polymer composites. The incorporation of nanomaterials into polymer matrices has garnered considerable attention due to the potential for enhancing material performance. The existing literature lacks in providing a thorough understanding of the intricate impacts of MWCNTs on PAEK composites, motivating the need for this research. The study examines the varied concentrations of MWCNT and functionalized (carboxyl and amine) MWCNT as 0.25, 0.5 and 0.75 weight percentages. These composites were prepared using a twin-screw extruder via the melt compounding method. The specimens were meticulously prepared through injection molding, adhering to American Society for Testing and Materials (ASTM) standards. Samples were assessed for tensile strength, impact strength, flexural strength, heat deflection temperature, hardness, and density. The key findings reveal a significant and gradual improvement in tensile strength, impact strength, flexural strength, and heat deflection temperature up to a 0.5% filler loading, followed by a reduction at higher concentrations of filler in PAEK matrices. Remarkably, the most notable improvements are observed with amine functionalized MWCNT. These findings highlight the potential of functionalized MWCNTs in enhancing the mechanical properties of PAEK polymer composites. The implications of this study offer valuable insights for material scientists, engineers, and industries aiming to enhance the performance of PAEK-based materials. The identified results provide advanced polymer composites for specific applications. [ABSTRACT FROM AUTHOR]

Electrospinning is a technique that can produce cost‐efficient, large output, very permeable membranes with high surface‐to‐mass ratio, and be used for many different applications. In this research, poly(ether sulfone) (PES) electrospun fibers were prepared for potential application in oil/water separation. A comprehensive investigation was carried out to study how the performance of the electrospun fibers is influenced by various operating conditions and the composition of the solution. The electrospun mats were evaluated by SEM, tensile test, TGA, and water contact angle techniques. The morphology of the fabricated membranes has been altered due to changes in the process and solution parameters. This alteration is evident when comparing mats that have been solely electrospray to those with the highest density of junctions between the nanofibers. Due to the utilization of a combination of solvents, namely N,N‐dimethylformamide, and N‐methyl‐pyrrolidinone (DMF/NMP), the mechanical properties of the fabricated membranes were enhanced. With this trick, a membrane with a tensile strength of 8.9 MPa was obtained, which had a relatively good performance in oil/water separation. This enhancement occurs through the improved fusion of inter‐fiber junction points, which is facilitated by the presence of NMP, a high vapor pressure component, in the solvent mixture. Thermal analysis showed suitable thermal stability for a model of prepared membranes. The prepared PES membrane in optimum electrospinning condition, was used in the oil/water separation process and was found to be 80% efficient. Oil/water separation experiments for PES showed its bright future in the treatment of oil/water wastewater. Highlights: The effect of solution and process parameters was studied on PES electrospinning.The tensile strength of the membrane was improved by using DMF/NMP solvent.The PES membrane showed its bright future in the oil/water separation. [ABSTRACT FROM AUTHOR]

The study is dedicated to the consideration of lower alkyl ethers of glycerol as potential components of low-melting technical fluids (e.g., heat transfer fluids, hydraulic fluids, aircraft de-icing fluids, etc.). Four isomeric mixtures of glycerol ethers (GMME—monomethyl; GDME—dimethyl; GMEE—monoethyl; GDEE—diethyl) were synthesized from epichlorohydrin and methanol/ethanol in the presence of sodium and subjected to detailed characterization as pure compounds and as aqueous solutions (30–90 vol%). The temperature and concentration dependencies of density, viscosity, cloud point, boiling range, specific heat capacity, thermal conductivity, and rubber swelling were obtained. On the basis of the data obtained, a comparison was made between the aqueous solutions of glycerol ethers and of other common bases for low-melting liquids (glycerol, ethylene glycol, and propylene glycol). Pure glycerol ethers could potentially be used as technical fluids in a very wide temperature range—from −114 to 150 °C. It was further demonstrated that in low temperature applications (e.g., in low-temperature chiller systems) the glycerol-ether-based aqueous heat transfer fluids could provide enhanced efficiency when compared to the glycerol- or propylene-glycol-based ones due to their lower viscosities and favorable environmental properties. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) presents a significant challenge to global healthcare systems, with current treatments offering only modest relief and often bringing unwanted side effects, necessitating the exploration of more effective and safer drugs. In this study, we employed the Caenorhabditis elegans (C. elegans) model, specifically the AD-like CL4176 strain expressing the human Aβ(1–42) protein, to investigate the potential of Reineckia carnea extract and its fractions. Our results showed that the Reineckia carnea ether fraction (REF) notably diminished the paralysis rates of CL4176 worms. Additionally, REF also attenuated the neurotoxicity effects prompted by Tau proteins in the BR5270 worms. Moreover, REF was observed to counteract the accumulation of Aβ and pTau proteins and their induced oxidative stress in C. elegans AD-like models. Mechanistic studies revealed that REF's benefits were associated with the induction of autophagy in worms; however, these protective effects were nullified when autophagy-related genes were suppressed using RNAi bacteria. Together, these findings highlight Reineckia carnea ether fraction as a promising candidate for AD treatment, warranting further investigation into its autophagy-inducing components and their molecular mechanisms. [ABSTRACT FROM AUTHOR]

A known dihydrofuranocoumarin ester; deltoin (1), together with five known sesquiterpene coumarin ethers; umbelliprenin (2), farnesyl scopoletin (3), karatavicinol (4), colladonin (5), colladin (6), and a novel sesquiterpene coumarin ether; 14′-hydroxybadrakemin (7) were isolated from the cytotoxic dichloromethane extract of the roots of Heptaptera triquetra. The cytotoxic activity of the isolated coumarins were evaluated against COLO205 (colon), KM12 (colon), A498 (renal) and UO31 (renal) cancer cell lines. [ABSTRACT FROM AUTHOR]

Density and viscosity measurements were carried out at 25 °C (298.15 K) on six binary di(or tri)glyme/organic carbonate (dimethylcarbonate, ethylene carbonate or propylene carbonate) systems and on multicomponent systems containing di(or tri)glyme/ organic carbonate mixtures. The effect of the organic carbonate composition on the excess weight volume (VwE), the deviation viscosity ( Δ η ), the partial weight and apparent weight volumes of glymes is interpreted in terms of competitive interactions and/or of differences in size or shape between glymes and organic carbonates. In addition, a model, based on viscosity data, is developed for the first time to determine the hydrodynamic volumes of glymes. The comparison of hydrodynamic volumes with Van der Waals volumes makes it possible to highlight and quantify the possible interactions between glymes and pure organic carbonates, and the association of triglyme molecules in organic carbonate EC/PC mixtures. The effect of LiPF6 and NaPF6 salts at 1 mol⋅L−1 in the glyme/organic carbonate mixtures appears to significantly reduce the volumes of glymes. By this, the strong interactions between salts and glymes are shown. [ABSTRACT FROM AUTHOR]

Poly (lactic acid) (PLA) is a promising green substitute for conventional petroleum-based plastics in a variety of applications. However, the wide application of PLA is still limited by its disadvantages, such as slow crystallization rate, inadequate gas barrier, thermal degradation, etc. In this study, lignin (1, 3, 5 PHR) was incorporated into PLA to improve the thermal, mechanical, and barrier properties of PLA. Two low-viscosity epoxy resins, ethylene glycol diglycidyl ether (EGDE) and poly (ethylene glycol) diglycidyl ether (PEGDE), were used as compatibilizers to enhance the performance of the composites. The addition of lignin improved the onset degradation temperature of PLA by up to 15 °C, increased PLA crystallinity, improved PLA tensile strength by approximately 15%, and improved PLA oxygen barrier by up to 58.3%. The addition of EGDE and PEGDE both decreased the glass transition, crystallization, and melting temperatures of the PLA/lignin composites, suggesting their compatabilizing and plasticizing effects, which contributed to improved oxygen barrier properties of the PLA/lignin composites. The developed PLA/lignin composites with improved thermal, mechanical, and gas barrier properties can potentially be used for green packaging applications. [ABSTRACT FROM AUTHOR]

The activation of ethers by weak interactions is a long-standing objective in supramolecular catalysis, but yet it remains an underdeveloped topic. The obstacles towards solving this problem are prominent since it is difficult for a weak interaction to cleave a relatively strong C-O σ-bond and moreover, the ionic intermediate composing of an alkoxide ion and an electrophilic carbocation would deactivate weak interaction donors. Herein, we describe a distinctive activation mode, dual Se···π and Se···O bonding, that could activate benzylic as well as allylic ether C-O σ-bonds to achieve cyclization, coupling and elimination reactions. This dual Se···π and Se···O bonding catalysis approach could tolerate various alkoxide leaving groups, while the other representative weak interaction donors showed no catalytic activity. The activation of ethers by weak interactions in supramolecular catalysis remains challenging. Here, the authors describe an activation mode based on dual Se···π and Se···O bonding, that can activate benzylic as well as allylic ether C-O σ-bonds to achieve cyclization, coupling and elimination reactions. [ABSTRACT FROM AUTHOR]

Electrospray printing is an additive manufacturing technique where a precursor solution composed of a solute material in a compatible solvent is subjected to a high electric potential, generating a spray of charged, solvent-encapsulated particles. Due to the high surface area to volume ratio, the solvent rapidly evaporates to deposit dry or partially-wet solute material onto a target surface. Over time, a thin continuous film is formed. Material emitted by electrospray is highly charged and will follow the electric field lines established between the emitter and a grounded target. As a result, this process is best suited for deploying material onto (grounded) conductive surfaces and can be used to create conformal coatings, even on non-line-of-sight surfaces. In contrast, delivering material to insulating surfaces is more difficult due to the accumulation of charge on the target, inhibiting the deposition of the solute and preventing the formation of a continuous film. We report on a new approach to improve deposition on dielectric (insulating) targets by manipulating the electric field and distribution of charge in the vicinity of the target surfaces. Colloidal silver in triethylene glycol monomethyl ether is deployed to create a conformal coating on packages consisting of a (i) broadband radiator encapsulated in epoxy molding compound, and (ii) a model silicon flip chip assembly. We seek to replace board level shielding and provide electromagnetic interference protection for a system-in-package at frequencies from 100 MHz to 6 GHz, with a target of 60 dB of isolation at 1 GHz. [ABSTRACT FROM AUTHOR]

Lariat ethers are macrocyclic polyethers—crown ethers—to which sidearms are appended. 4,13-Diaza-18-crown-6 having twin alkyl chains at the nitrogens show biological activity. They exhibit antibiotic activity, but when co-administered at with an FDA-approved antibiotic, the latter's potency is often strongly enhanced. Potency enhancements and resistance reversals have been documented in vitro for a range of Gram-negative and Gram-positive bacteria with a variety of antimicrobials. Strains of E. coli and Staphylococcus aureus having resistance to a range of drugs have been studied and the potency enhancements (checkerboards) are reported here. Drugs included in the present study are ampicillin, cefepime, chlortetracycline, ciprofloxacin, doxycycline, kanamycin, minocycline, norfloxacin, oxycycline, penicillin G, and tetracycline. Enhancements of norfloxacin potency against S. aureus 1199B of up to 128-fold were observed. The properties of these lariat ethers have been studied to determine solubility, their membrane penetration, cytotoxicity and mammalian cell survival, and their effect on bacterial efflux pumps. It is shown that in some cases, the lariat ethers have complex antimicrobials with considerable selectivity. Based on these observations, including 1:1 complexation between lariat ethers and antimicrobials and the cytotoxicity of the MeI salts showing a separation index of 32-fold, they hold significant potential for further development. [ABSTRACT FROM AUTHOR]

Ethylene glycol (EG) produced from biomass is a promising candidate for several new applications. In this paper, EG derivatives such as mono- and di-tert-butyl ethers are considered. However, accurate thermodynamic data are essential to optimise the technology of the direct tert-butyl ether EG synthesis reaction or reverse process isobutene release. The aim of this work is to measure the vapour pressures and combustion energies for these ethers and determine the vaporisation enthalpies and enthalpies of formation from these measurements. Methods based on the First and Second Law of Thermodynamics were combined to discover the reliable thermodynamics of ether synthesis reactions. The thermochemical data for ethylene glycol tert-butyl ethers were validated using structure–property correlations and quantum chemical calculations. The literature results of the equilibrium study of alkylation of EG with isobutene were evaluated and the thermodynamic functions of ethylene glycol tert-butyl ethers were derived. The energetics of alkylation determined according to the “First Law” and the “Second Law” methods agree very well. Some interesting aspects related to the entropy of ethylene glycol tert-butyl ethers were also revealed and discussed.

Background: Bauhinia thonningii is a plant traditionally used against many human diseases such as gastric ulcers, fever, inflammations, coughs, dysentery, diarrhea, and malaria. In the present investigation, the cytotoxicity of methanol extract of Bauhinia thonningii leaves (BTL), fractions and the isolated phytoconstituents was determined in a panel of 9 human cancer cell lines including drug sensitive and multidrug-resistant (MDR) phenotypes. The acute and sub-chronic oral toxicity of BTL was investigated as well. Methods: Compounds were isolated using chromatographic techniques while their chemical structures were determined using spectroscopic methods. The resazurin reduction assay (RRA) was used to evaluate the cytotoxicity of samples, propidium iodide (PI) for apoptosis, 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylbenzimidazolylcarbocyanine iodide (JC-1) staining for mitochondrial membrane potential (MMP) analysis, 2´,7´-dichlorodihydrofluoresceine diacetate (H2DCFH-DA) staining for the quantification of reactive oxygen species (ROS), whereas Caspase Glo assays were combined by means of flow cytometry. Furthermore, the toxicological investigations were performed as recommended by the Organization for Economic Cooperation and Development (OECD). Results: The botanicals as well as 6-C-methylquercetin-3,7-dimethyl ether (2), quercetin-3-O-L-rhamnopyranoside (5), quercetin-3-O-β-glucopyranoside (6), 6,8-C-dimethylkaempferol 3,7-dimethyl ether (7), and 6,8-C-dimethylkaempferol-3-methyl ether (8) had promising cytotoxic effects in the 9 tested cancer cell lines. The IC50 values below 20 µg/mL (botanicals) or 10 µM (compounds) on at least 1/9 tested cancer cell lines were considered. The best cytotoxic effects with IC50 values below 5 µM were achieved with compounds 7 against CEM/ADR5000 leukemia cells (2.86 µM) and MDA-MB-231-pcDNA breast adenocarcinoma cells (1.93 µM) as well as 8 against CCRF-CEM leukemia cells (3.03 µM), CEM/ADR5000 cells (2.42 µM), MDA-MB-231-pcDNA (2.34 µM), and HCT116 p53−/− cells (3.41 µM). BTL and compound 8 induced apoptotic cell death in CCRF-CEM cells through caspase activation, alteration of MMP, and increased ROS production. BTL did not cause any adverse effects in rats after a single administration at 5000 mg/kg or a repeated dose of 250 mg/kg body weight (b. w.). Conclusion: Bauhinia thonningii and its constituents are sources of cytotoxic drugs that deserve more in-depth studies to develop novel antiproliferative phytomedicine to fight cancer including resistant phenotypes. [ABSTRACT FROM AUTHOR]

BACKGROUND: Children are routinely exposed to chemicals known or suspected of harming brain development. Targeting Environmental Neuro- Development Risks (Project TENDR), an alliance of >50 leading scientists, health professionals, and advocates, is working to protect children from these toxic chemicals and pollutants, especially the disproportionate exposures experienced by children from families with low incomes and families of color. OBJECTIVE: This scoping review was initiated to map existing literature on disparities in neurodevelopmental outcomes for U.S. children from population groups who have been historically economically/socially marginalized and exposed to seven exemplar neurotoxicants: combustion-related air pollution (AP), lead (Pb), mercury (Hg), organophosphate pesticides (OPs), phthalates (Phth), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs). METHODS: Systematic literature searches for the seven exemplar chemicals, informed by the Population, Exposure, Comparator, Outcome (PECO) framework, were conducted through 18 November 2022, using PubMed, CINAHL Plus (EBSCO), GreenFILE (EBSCO), and Web of Science sources. We examined these studies regarding authors’ conceptualization and operationalization of race, ethnicity, and other indicators of sociodemographic and socioeconomic disadvantage; whether studies presented data on exposure and outcome disparities and the patterns of those disparities; and the evidence of effect modification by or interaction with race and ethnicity. RESULTS: Two hundred twelve individual studies met the search criteria and were reviewed, resulting in 218 studies or investigations being included in this review. AP and Pb were the most commonly studied exposures. The most frequently identified neurodevelopmental outcomes were cognitive and behavioral/psychological. Approximately a third (74 studies) reported investigations of interactions or effect modification with 69% (51 of 74 studies) reporting the presence of interactions or effect modification. However, less than half of the studies presented data on disparities in the outcome or the exposure, and fewer conducted formal tests of heterogeneity. Ninety-two percent of the 165 articles that examined race and ethnicity did not provide an explanation of their constructs for these variables, creating an incomplete picture. DISCUSSION: As a whole, the studies we reviewed indicated a complex story about how racial and ethnic minority and low-income children may be disproportionately harmed by exposures to neurotoxicants, and this has implications for targeting interventions, policy change, and other necessary investments to eliminate these health disparities. We provide recommendations on improving environmental epidemiological studies on environmental health disparities. To achieve environmental justice and health equity, we recommend concomitant strategies to eradicate both neurotoxic chemical exposures and systems that perpetuate social inequities. [ABSTRACT FROM AUTHOR]