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The homogeneous Fenton process involves both coagulation and oxidation, but it requires added acidity, so it is rarely used to control membrane fouling. This work found that the pH of neutral simulated wastewater sharply declined to 4.1 after pre-treatment with 0.1 mM Fenton reagent (Fe 2+ :H 2 O 2 =1:1) without added acidity. This occurred mainly because the trace homogeneous Fenton reagent induced in situ acid production by organic matter in the wastewater, which supplied the acidic conditions required for the Fenton reaction and ensured that the reaction could proceed continuously. Then, oxidation during the pre-Fenton process enhanced the electrostatic repulsion forces and effectively weakened the hydrogen bonds of organic matter at the membrane surface by altering the net charge and hydroxyl content of organic matter, while coagulation caused the foulants to gather and form large aggregates. These changes diminished the deposition of foulants onto the membrane surface and resulted in a looser fouling layer, which eventually caused the membrane fouling rate to decline from 83 % to 24 % and the flux recovery rate to increase from 44 % to 98 % during 2 h of filtration. This membrane fouling mitigation ability is much superior to that of pre-H 2 O 2 , pre-Fe 2+ or pre-Fe 3+ processes with equivalent doses., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Preparation of the NC-Cu@Ti electrode involved electrochemical deposition of nanocrystalline copper on the surface of titanium foil using a constant potential method, intended for high stability anode-free zinc ion battery (ZIB) anode material applications. This paper examines the effect of Cu 2+ concentration in the electrodeposition solution on the structure and morphology of copper crystals on the NC-Cu@Ti electrode surface. The study also assesses how the interfacial properties of the NC-Cu@Ti electrode affect the process of anodic zinc deposition without anodic ZIBs. Our data suggest that with a voltage setting of -0.95 V and a copper ion concentration of 0.5 M in the solution, the deposition rate of copper crystals on the NC-Cu@Ti-0.5 electrode remains consistent. The resultant crystal phase surface appears smooth with a fine grain size. The NC-Cu@Ti-0.5 electrodes have increased hydrogen potentials and superior corrosion resistance; noting zinc nucleation sites at a mere 21.4 mV, it can provide stable electrochemical conditions for the zinc deposition interface of ZIBs and accelerate the process of zinc desolvation and nucleation. The constructed Zn//NC-Cu@Ti-0.5 asymmetric cell displays swift zinc deposition/stripping kinetics, elevated Coulombic efficiency, and prolonged stability (maintaining nearly 99% after 200 cycles). This performance significantly extends the service life relative to the Zn//Zn symmetric cell, which operates stably for 400 h at 1 mA/cm 2 . Moreover, the NC-Cu@Ti-0.5//MnO 2 ZIBs offer enhanced conductivity and magnification performance to the pure zinc anode ZIBs. This study presents a novel approach for the low-cost and rapid preparation of anode materials for high-performance free-anode ZIBs.

Protein palmitoylation, a cellular process occurring at the membrane-cytosol interface, is orchestrated by members of the DHHC enzyme family and plays a pivotal role in regulating various cellular functions. The M2 protein of the influenza virus, which is acylated at a membrane-near amphiphilic helix serves as a model for studying the intricate signals governing acylation and its interaction with the cognate enzyme, DHHC20. We investigate it here using both experimental and computational assays. We report that altering the biophysical properties of the amphiphilic helix, particularly by shortening or disrupting it, results in a substantial reduction in M2 palmitoylation, but does not entirely abolish the process. Intriguingly, DHHC20 exhibits an augmented affinity for some M2 mutants compared to the wildtype M2. Molecular dynamics simulations unveil interactions between amino acids of the helix and the catalytically significant DHHC and TTXE motifs of DHHC20. Our findings suggest that the binding of M2 to DHHC20, while not highly specific, is mediated by requisite contacts, possibly instigating the transfer of fatty acids. A comprehensive comprehension of protein palmitoylation mechanisms is imperative for the development of DHHC-specific inhibitors, holding promise for the treatment of diverse human diseases., (© 2023. The Author(s).)

Heavy metal pollution can significantly harm water systems and human health. Combining photoelectrocatalytic (PEC) and nanofiltration (NF) membrane separation technologies can effectively remove heavy metal ions from wastewater. In this study, a water bath method was used to form SrF 2 /Ti 3 C 2 T x (ST) nanoparticles on the surface of polyvinylidene fluoride (PVDF) membranes and an additional polyamide (PA) functional layer was formed at the interface by crosslinking. ST@PA composite NF membranes (STPP) with good photocatalytic performance were obtained. The separation and catalytic properties of the STPP membranes were controlled by the ST content, which modifies the surface structure and properties of the membranes. The membrane with optimal ST crosslinking exhibited a water contact angle of 50.8°, pure water flux of 24.6 L·m -2 ·h -1 ·bar -1 , and rejection rates of Mn 2+ , Ni 2+ , Cu 2+ , and Zn 2+ of 98.8%, 95.3%, 95.7%, and 97.3%, respectively, under PEC-assisted separation with visible light illumination from a Xe lamp (300 W) and an applied voltage (2 V). The STPP membranes showed improved rejection rates of heavy metal ions under PEC-assisted operation. The mechanism for the improved membrane performance under PEC conditions was preliminarily clarified considering the relationship between the photocatalytic and filtration properties of STPP membranes along with the influence of light irradiation and an external voltage on the heavy metal ions. The generation of electrons, holes, superoxide radicals, and hydroxyl radicals during membrane operation enhances the rejection rates of heavy metal ions. Based on these results, STPP membranes are considered a promising technology for industrial applications in heavy metal removal., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Importance: Influenza viruses are a public health concern since they cause seasonal outbreaks and occasionally pandemics. Our study investigates the importance of a protein modification called "palmitoylation" in the replication of influenza B virus. Palmitoylation involves attaching fatty acids to the viral protein hemagglutinin and has previously been studied for influenza A virus. We found that this modification is important for the influenza B virus to replicate, as mutating the sites where palmitate is attached prevented the virus from generating viable particles. Our experiments also showed that this modification occurs in the endoplasmic reticulum. We identified the specific enzymes responsible for this modification, which are different from those involved in palmitoylation of HA of influenza A virus. Overall, our research illuminates the similarities and differences in fatty acid attachment to HA of influenza A and B viruses and identifies the responsible enzymes, which might be promising targets for anti-viral therapy., Competing Interests: The authors declare no conflict of interest.

Owing to the symbiotic relationship between the microbiota and the human body, the microbiome is considered a "second human genome". Microorganisms are inextricably associated with human diseases and can affect the host phenotype. In the present study, 25 female patients with stage 5 chronic kidney disease (CKD5) undergoing hemodialysis in our hospital and 25 healthy subjects were recruited. The structure of the oral microbiota of the study participants was analyzed using the MiSeq PE300 sequencing platform and high-throughput 16S rDNA sequencing. The microbiota was compared between the groups using QIIME and the stats package in R. In total, 1,336 operational taxonomic units (OTUs) were obtained, and the relative frequencies of 450 OTUs differed significantly between the two groups (P < 0.05), indicating that the samples were rich in OTUs. A comparison of β-diversity indicated a significant difference in the microbial community structure between the two groups (P < 0.05). These results indicated that the biological diversity of the oral microbiota was highly correlated with CKD5. In this experiment, 189 genera, with significant differences in abundance between the groups (P < 0.05), were found. Furthermore, differences in the structure of the oral microbiota were observed between the groups at the phylum, class, order, family, and genus levels. Collectively, an imbalance in the oral microbiota may accelerate the progression of CKD and cause additional complications., Competing Interests: None., (AJTR Copyright © 2023.)

We present an efficient and easy synthesis method for incorporating organocatalytic moieties into Zr-metal organic frameworks (Zr-MOFs). The catalytic activity and selectivity of the new chiral catalysts were improved by adjusting the aperture of the MOF cavities. The hole size of the Zr-MOF was modulated by adding acid and replacing bridge ligands during synthesis. The difunctional chiral units of amino acid-thiourea are anchored onto the Zr-MOF by a mild synthesis method from an isothiocyanate intermediate which could effectively avoid the racemization of chiral moieties in the synthesis process. By means of specific surface area measurement (BET), scanning electron microscopy (SEM) and powder X-ray Diffraction (PXRD), it was confirmed that Zr-MOFs with different pore sizes were synthesized without breaking the basic octahedral structure of the MOF. Finally, good yields (up to 83%) and ee values (up to 73%) were achieved with the new heterogeneous catalysts in 48 hours for the aldol reaction of 4-nitrobenzaldehyde with acetone. By contrast, using the catalyst support without modulating the synthesis, the yield (30%) and the ee-value (26%) were both low. Experiments have confirmed the important influence on the reaction selectivity of providing a suitable reaction environment by controlling the aperture of MOF cavities., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Emerging infectious diseases, especially if caused by bat-borne viruses, significantly affect public health and the global economy. There is an urgent need to understand the mechanism of interspecies transmission, particularly to humans. Viral genetics; host factors, including polymorphisms in the receptors; and ecological, environmental, and population dynamics are major parameters to consider. Here, we describe the taxonomy, geographic distribution, and unique traits of bats associated with their importance as virus reservoirs. Then, we summarize the origin, intermediate hosts, and the current understanding of interspecies transmission of Middle East respiratory syndrome coronavirus (MERS-CoV), severe acute respiratory syndrome coronavirus (SARS-CoV), SARS-CoV-2, Nipah, Hendra, Ebola, Marburg virus, and rotaviruses. Finally, the molecular interactions of viral surface proteins with host cell receptors are examined, and a comparison of these interactions in humans, intermediate hosts, and bats is conducted. This uncovers adaptive mutations in virus spike protein that facilitate cross-species transmission and risk factors associated with the emergence of novel viruses from bats., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Multiband-compatible stealth materials play an increasingly crucial role in the field of modern military defence because they can enable the targeted objects to dodge advance detection technologies. In this study, chain-like Fe 3 O 4 @poly(ethyleneglycol dimethacrylate-co-methacrylic acid) nanocomposites were constructed as precursors through the magnetic field-induced distillation precipitation polymerisation. Then, the liquid-phase seed-mediated growth method, together with subsequent calcination, was applied to introduce SnO 2 shells and remove poly(ethyleneglycol dimethacrylate-co-methacrylic acid) shells, which led to the successful preparation of innovative core-shell Fe 3 O 4 @SnO 2 nanochains. The unique microstructure and appropriate components endowed nanochains with multiple functional applications. The minimum reflection loss value was approximately -39.4 dB (5.67 GHz), exhibiting excellent microwave absorption performance. The possible microwave absorption mechanisms involve interfacial polarisation, space charge polarisation, natural resonance, and multiple reflections and scatterings. The optimal infrared reflectivity reached 0.64, 0.51, and 0.37 in three atmospheric windows, indicating outstanding infrared stealth performance, which was attributed to the intense infrared reflection of SnO 2 shells. Furthermore, three nanochains showed different colours (dark green, brick red, and bright orange), revealing selection absorption for visible light. This can be attributed to the combined effect of visible responses of SnO 2 shells along with Bragg diffraction from the periodic arrangement of Fe 3 O 4 particles in a single nanochain. Thus, core-shell Fe 3 O 4 @SnO 2 nanochains can be considered as promising radar-infrared-visible compatible stealth materials. This discovery opens a new means to exploit multiband-compatible stealth materials., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Recent pandemics of zoonotic origin were caused by members of coronavirus (CoV) and influenza A (Flu A) viruses. Their glycoproteins (S in CoV, HA in Flu A) and ion channels (E in CoV, M2 in Flu A) are S-acylated. We show that viruses of all genera and from all hosts contain clusters of acylated cysteines in HA, S and E, consistent with the essential function of the modification. In contrast, some Flu viruses lost the acylated cysteine in M2 during evolution, suggesting that it does not affect viral fitness. Members of the DHHC family catalyze palmitoylation. Twenty-three DHHCs exist in humans, but the number varies between vertebrates. SARS-CoV-2 and Flu A proteins are acylated by an overlapping set of DHHCs in human cells. We show that these DHHC genes also exist in other virus hosts. Localization of amino acid substitutions in the 3D structure of DHHCs provided no evidence that their activity or substrate specificity is disturbed. We speculate that newly emerged CoVs or Flu viruses also depend on S-acylation for replication and will use the human DHHCs for that purpose. This feature makes these DHHCs attractive targets for pan-antiviral drugs.

The development of the electroplating and battery industries has increased the environmental problems and the needs for resource recovery of Cd(II). In this study, the Electro-membrane extraction (EME) behaviour of Cd(II) was investigated by using polymer inclusion membrane with bis(2-ethylhexyl) phosphate as carrier and polyvinyl chloride as base polymer(PD-PIM) at 0-80 V. Results showed that the EME of Cd(II) by PD-PIM can be obtained in the feed phase with pH 3-8 and stripping phase of dilute acid. Voltage is the main factor to increase the mass transfer rate of Cd(II). The applied electric field reduced the mass transfer activation energy of Cd(II) by PD-PIM and weakened the mass transfer interference of Cd(II) on the background material of the feed phase. After using kerosene-stabilised PD-PIM for operation at pH5, 60 V for 120 h, Cd(II) in the 1 L solution reduced from 15 mg/L to 0.08 mg/L, and the enrichment factor was 9.79., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A polymer inclusion membrane (PIM) that contains a polyvinyl chloride (PVC) polymer matrix and 1-octanol (OCT) as specific carrier (PO-PIM) was prepared to investigate the mass transfer behaviour of phenol in aqueous solutions. Results showed that the mass transfer behaviour of the PO-PIM for phenol conformed to the first-order kinetics. In addition, the mass transfer efficiency for phenol reached the maximum when the OCT content was 82.8 wt%. The mass transfer activation energy (E a ) was 14.46 kJ mol -1 , which indicated that intramembranous diffusion was the main controlling factor in the mass transfer process. The introduction of hydrophobic additives, such as kerosene, liquid paraffin and vegetable oil, into the PO-PIM could remarkably improve its stability. In an aqueous solutions of phenol ranging from 0 mg L -1 to 9000 mg L -1 , the initial flux (J 0 ) of kerosene/PVC/OCT-PIM (KPO-PIM) was positively correlated with the initial concentration of phenol. For a stripping solution with a feed solution pH of 2.0 and a sodium hydroxide concentration of 0.1 mol L -1 , the maximum permeability coefficient during stable mass transfer reached 12.55 μm s -1 . At a mass transfer area of 3.14 cm 2 , an enrichment factor (EF) of 3.5 for 200 mg L -1 of phenolic aqueous solution was achieved within 48 h through KPO-PIM., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

To investigate how the characteristics of pregenerated organic fouling layers on nanofiltration (NF) membranes influence the subsequent gypsum scaling behavior, filtration experiments with gypsum were carried out with organic-fouled poly(piperazineamide) NF membranes. Organic fouling layer on membrane was induced by bovine serum albumin (BSA), humic acid (HA), and sodium alginate (SA), respectively. The morphology and components of the scalants, the role of Ca(2+) adsorption on the organic fouling layer during gypsum crystallization, and the interaction forces of gypsum on the membrane surface were investigated. The results indicated that SA- and HA-fouled membranes had higher surface crystallization tendency along with more severe flux decline during gypsum scaling than BSA-fouled and virgin membranes because HA and SA macromolecules acted as nuclei for crystallization. Based on the analyses of Ca(2+) adsorption onto organic adlayers and adhesion forces, it was found that the flux decline rate and extent in the gypsum scaling experiment was positively related to the Ca(2+)-binding capacity of the organic matter. Although the dominant gypsum scaling mechanism was affected by coupling physicochemical effects, the controlling factors varied among foulants. Nevertheless, the carboxyl density of organic matter played an important role in determining surface crystallization on organic-fouled membrane., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Fouling behaviours and antifouling properties of polyvinylidene fluoride (PVDF) ultrafiltration membranes blending with polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP) and polymethyl methacrylate (PMMA) had been investigated using the secondary effluent as the filtration medium. The results demonstrated that the antifouling properties of membranes using PVA and PVP as the additives were generally stronger than those using PMMA. Additives PVA and PVP could effectively improve the structural property and hydrophilicity of the membrane and result in an outstanding antifouling property. A dense membrane surface could prevent low molecular foulants from entering into the membrane pores, depositing on the membrane with a loose spongy layer and penetrating into the internal macropore structure. The not fully generated internal macropores on the membrane surface were trend to be plugged, which resulted in serious flux decay and the membrane fouling was irreversible. Filtration cake formed on the membrane due to concentration polarization, which caused membrane flux decline and high flux recovery after cleaning.

To determine further the enhancement and mitigation mechanisms of protein fouling, filtration experiments were carried out with polyvinylidene fluoride (PVDF) ultrafiltration (UF) membranes and bovine serum albumin (BSA) over a range of ionic strengths. The interaction forces, the adsorption behavior of BSA on the membrane surface, and the structure of the BSA adsorbed layers at corresponding ionic strengths were investigated. Results indicate that when the ionic strength increased from 0 to 1 mM, there was a decrease in the PVDF-BSA and BSA-BSA electrostatic repulsion forces, resulting in a higher deposition rate of BSA onto the membrane surface, and the formation of a denser BSA layer; consequently, membrane fouling was enhanced. However, at ionic strengths of 10 and 100 mM, membrane fouling and the BSA removal rate decreased significantly. This was mainly due to the increased hydration repulsion forces, which caused a decrease in the PVDF-BSA and BSA-BSA interaction forces accompanied by a decreased hydrodynamic radius and increased diffusion coefficient of BSA. Consequently, BSA passed more easily through the membrane and into permeate. There was less accumulation of BSA on the membrane surface. A more nonrigid and open structure BSA layer was formed on the membrane surface.

To further unravel the organic fouling behavior of polyvinylidene fluoride (PVDF) ultrafiltration (UF) membranes, the adhesion forces of membrane-foulant and foulant-foulant were investigated by atomic force microscopy (AFM) in conjunction with self-made PVDF colloidal probe and foulant-coated colloidal probe, respectively. Fouling experiments with bovine serum albumin, sodium alginate, humic acid, and secondary wastewater effluent organic matter (EfOM) were carried out with PVDF UF membrane. Results showed a positive correlation between the membrane-foulant adhesion force and the flux decline rate and extent in the initial filtration stage, whereas the foulant-foulant interaction force was closely related to the pseudostable flux and the cake layer structure in the later filtration stage. For each type of foulant used, the membrane-foulant adhesion force was much stronger than the foulant-foulant interaction force, and membrane flux decline mainly occurred in the earlier filtration stage indicating that elimination of the membrane-foulant interaction force is important for the control of membrane fouling. Upon considering the foulant-foulant interaction force and the membrane flux recovery rate of fouled membranes, it was evident that the main contributor to physically irreversible fouling is the foulant-foulant interaction force.

By adopting the bifunctional group reagent methylene-di-paraphenylene iso-cyanate (MDI), a ring antibiotic chiral stationary phase (CSP) was prepared in non-aqueous dimethylfomamide (DMF) with vancomycin which is a macrocyclic glycopeptide antibiotics bonded on gamma-amidopropyl silica gel. It was used in the chiral separation in high performance liquid chromatography. The results showed that vancomycin CSP synthesized in this way can be well used in enantiomer separation of the chiral compounds in normal and reversed-phase. It can be confirmed that the separation capability in reversed-phase is better than that in normal phase. Seventeen pairs of enantiomers were separated in reversed-phase mode, and the results showed a wide range of application. The phosphorus buffer system was better than the triethylamineacetic acid buffer system. The resolution of some chiral drugs such as D,L-dansyl amino acid has certain rule, and provides information about absolute configuration. The aging or denaturalization can not happen in the CSP when phase system was transformed, so it has some stability. The mechanism of the separation was analyzed and found to be the same as that of Armstrong.