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A spontaneous fuel cell is developed in this paper to treat benzoic acid, a precursor of several organic pollutants found in agro-industrial effluents. The innovative concepts behind the cell design are that at room temperature and atmospheric pressure, the reactor could accelerate the removal of benzoic acid and the generation of electricity. Experiments were performed to investigate the influences of hydrogen peroxide concentration, flow rate, electrolyte concentration, and the pH value of hydrogen peroxide solution to optimize the operating parameters for the spontaneous fuel cell, while chemical oxygen demand analysis was performed to assess the extent of degradation. It was found that in the presence of benzoic acid (0.025 mol l), HO (10 %) and a flow rate of 13.5 ml per minute, the voltage reaches a stable value of 65 mV, and the current is 100 μA during the early stage of reaction, which is slightly lower than that of some microbial fuel cells. However, the microbial fuel cell is rather problematic because of its long treatment period, inhibitory properties, and secondary pollution. These results show that the spontaneous fuel cell is promising for energy reclamation with the removal of organics and might lead to consideration of the electrochemical role in wastewater treatment. [ABSTRACT FROM AUTHOR]

Disodium monoalkyl diphenyl oxide disulfonates (MADS) with different carbon chains (C-MADS, n = 8, 12, 16) were synthesized through the steps of alkylation-sulfonation-neutralization using fatty alcohols (C, C, C), diphenyl oxide and fuming sulfuric acid (20 % free SO) as reagents. The structures of the products were identified by infrared spectroscopy and electrospray ionization-mass spectrometry. The surface properties, emulsification, wettability alteration and salinity and hardness tolerance of the products were systematically investigated. The results show that the critical micelle concentration (CMC) of CMADS, CMADS and CMADS are 7.24 × 10, 1.49 × 10 and 2.09 × 10 mol/L. The surface tensions at the CMC ( γ) of each product are 37.5, 38.9 and 46.8 mN/m. The negative logarithm of the surfactant concentration in the bulk phase required to produce a 20 mN/m reduction in the surface tension of the solvent ( pC) increases with the increase in the alkyl chain length. The emulsifying ability of C-MADS is better than C-MADS and C-MADS, and the MADS showed less oil-wet nature. The salinity and hardness tolerance of MADS is much stronger than that of conventional surfactants. [ABSTRACT FROM AUTHOR]

C, as one of carbon nanomaterials widely used in various fields, could be released into the water environment thus exerting some potential health risks to human beings. This work examined the behavior of aqueous stable colloidal nano-C (nC) aggregates under different environmental conditions including Polyethylene glycol octylphenol ether (TX100) micelles concentration, pH, and reaction time when exposed to TX100 micelles. Results show that the nC aggregates became more dispersive and restored the capability of generating the singlet oxygen when exposed to TX100 micelles. With the increase of TX100 concentration, smaller average size of nC aggregates was observed in dynamic light scattering (DLS) analysis, the fluorescence intensity of TX100 was more quenched by nC aggregates, and the kinetic rate constant of generating the singlet oxygen for nC aggregates was improved. The mean size of nC aggregates in the presence of TX100 had no obvious variations when the pH ranged from 4 to 8. The longer reaction time between nC aggregates and TX100 led to a higher kinetic rate constant of generating the singlet oxygen. Collective data suggest that variations in physicochemical properties of nC aggregates are strongly dependent on the surrounding media under different environmental conditions and directly govern nC's transport behavior and potential toxicity. [ABSTRACT FROM AUTHOR]

Synergistic interactions between zwitterionic surface active ionic liquids (SAILs), N-alkyl-N′-carboxymethyl imidazoliumm inner salts ([N-Cn, N′-CO2-Im],n = 12, 14), and a traditional twin-tail anionic surfactant (dioctyl sulphosuccinate sodium salt, AOT) in aqueous solution has been studied by surface tension and fluorescence measurements at 298.15 K. The results imply that the mixed systems have superior surface activity in comparison to individual surfactant, and they all present a non-ideal behavior with synergism. The strength of interactions between two surfactants increases with the enhancement of the hydrocarbon chain of the zwitterionic SAILs. Compared with interaction parameters in mixed monolayer, the larger value of interaction parameters in mixed micelles indicates that the mixed micelle formation is more favorable. Additionally, a series of thermodynamic parameters such as the standard Gibbs free energy of adsorption (), the standard Gibbs free energy of micellization (), and excess free energy of micellization (ΔGex) have been calculated. The negative values ofandshow that both micellization and adsorption of surfactants are spontaneous, while the negative value of ΔGexindicates the formation of stable mixed micelles for [N-Cn, N′-CO2-Im]/AOT mixture, which can potentially be useful for industrial preparations and medicinal formulations. [ABSTRACT FROM AUTHOR]

Using CuI as a catalyst, N, N-diisopropylethylamine as ligand, n-butylamine as a base, and CHCN as solvent, the Glaser reaction of N-[5-( S)-alkoxy-2(5 H)-furanonyl] amino acid propargyl esters 1 at room temperature was investigated, and a series of new chiral 2(5 H)-furanone derivatives containing 1,3-butadiyne structure have been synthesized as designed, with yields of 49-84 % (mostly over 66 %). Sixteen target molecules 2 were characterized by FTIR, H NMR, C NMR, MS, and elemental analysis. The brief synthesis of the series 2(5 H)-furanones derivatives with different functional units will afford not only an important synthetic strategy for the bioactive 2(5 H)-furanone derivatives as potential drug molecules but also a basis for the chiral polydiacetylene materials. [ABSTRACT FROM AUTHOR]

The multifunctional fluorescent brighteningagents (FBAs) simultaneouslypossessing chiral 2(5H)-furanone and bis-1,2,3-triazolemoieties are synthesized as designed via the Click reaction of N-[(5S)-5-menthoxy-2(5H)-furanonyl] amino acid propargyl esters with 4,4′-diazidostilbene-2,2′-disulfonatesodium salt tetrahydrate in high yields (over 90%). Their structuresare systematically characterized. In addition, the testing resultsof their properties from fluorescence spectroscopy, photoisomerization,and ultraviolet (UV) protection factor (UPF) test show that the novelFBAs have excellent fastness to acid and light, as well as UV resistance.Especially, when a larger alkyl group in the side chain of amino acidmoiety is introduced into the structure of the FBA, the designed compoundhas a better fluorescent brightening effect as anticipated. Moreover,in the experiments of its sorption on paper fibers, the scanning electronmicroscopy (SEM) images with it show a rough surface, while otherswithout it show a relatively smooth surface. [ABSTRACT FROM AUTHOR]

In this paper, nichrome was adopted as a substrate, to fabricate the pre-anodized inlaying ultrathin carbon paste electrode (PAIUCPE). The electrochemical behaviors and diffusion mechanisms of three dihydroxybenzene isomers at the electrode were carefully investigated. The effect of pH on oxidation peak current was also detailedly explained. The results were shown that oxidation peak current not only related to the reaction of electroactive materials at the working electrode, but also depended on the reaction variable of reduction at the auxiliary electrode. The oxidation peaks of hydroquinone (HQ), catechol (CC) and resorcinol (RC) located at 0.181 V, 0.288 V and 0.736 V. For CC, RC and HQ, the oxidation peak currents were linear to the concentrations at the range of 5.0 × 10−6∼5.0 × 10−4 mol/L, 3.0 × 10−6∼5.0 × 10−4 mol/L and 4.0 × 10−6∼4.0 × 10−4 mol/L with the detection limits of 2.0 × 10−7 mol/L, 1.2 × 10−7 mol/L and 1.2 × 10−7 mol/L, respectively. The proposed method was successfully applied in the simultaneous determination of dihydroxybenzene isomers in artificial sewage samples with satisfactory results. [ABSTRACT FROM AUTHOR]

To further verify the forming mechanism of multi-core structure during the direct melt copolycondensation of lactic acid (LA) with the compounds containing multifunctional groups, the biodegradable material poly(lactic acid -co-glycerol) [P(LA- co-GL)] was synthesized as designed using L-lactic acid ( L-LA) and glycerol (GL) as the starting materials. For the molar feed ratio n(LA)/ n(GL) of 60/1, the optimal synthetic conditions were discussed. Using 0.3 wt% stannous oxide (SnO) as the catalyst, after the prepolymerization was carried out at 140 °C for 8 h, the melt copolymerization for 8 h at 160 °C gave the polymer with the biggest intrinsic viscosity ([ η]) 0.76 dL•g. The copolymers P(LA- co-GL)s at different molar feed ratios were characterized by Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (H-NMR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Increasing the molar feed ratio n(LA)/ n(GL), the weight-average molecular weight (M) didn't increase all the time, but a peak of M was formed, which indeed validated the above special phenomenon during the direct melt copolycondensation of LA with the monomers containing multifunctional groups. However, the forming mechanism of multi-core copolymer was different when multihydroxyl alcohol (e.g. GL) was used as the monomer containing multifunctional groups. Because the multi-core structure was linked by the ether bonds with less reversibility in the reaction, the biggest M of copolymers was relatively lower. For GL with three terminal hydroxyls as the core, only when n(LA)/ n(GL) was more than 100/1, the star-shaped polylactic acid (SPLA) containing one core could be obtained. [ABSTRACT FROM AUTHOR]

An environmentally friendly and lead-free perovskite CsBiBr 3 was co-doped by Ni and Mn successfully. Their structures and physicochemical features were systematically characterized. The biggest H 2 evolution rate reaches 61.8 μ mol g−1 h−1 for 1c under IR light irradiation, corresponding to an AQY of 0.67% and solar-to-chemical conversion efficiency of 0.46%, achieving 24 h-recycles of repeated H 2 generation. • An environmentally friendly and lead-free perovskite CsBiBr 3 was co-doped by Ni and Mn and characterized systematically. • Under IR light irradiation, 1c exhibits excellent photocatalytic properties and 24 h-recycles of repeated H 2 evolution. • This pioneering example offers a nanoplatform for tunable perovskite CsBiBr 3 nanomaterials. [ABSTRACT FROM AUTHOR]

Astrocytes play a pivotal role in maintaining the central nervous system (CNS) homeostasis and function. In response to CNS injuries and diseases, reactive astrocytes are triggered. By purifying and genetically profiling reactive astrocytes, it has been now found that astrocytes can be activated into two polarization states: the neurotoxic or pro-inflammatory phenotype (A1) and the neuroprotective or anti-inflammatory phenotype (A2). Although the simple dichotomy of the A1/A2 phenotypes does not reflect the wide range of astrocytic phenotypes, it facilitates our understanding of the reactive state of astrocytes in various CNS disorders. This article reviews the recent evidences regarding A1/A2 astrocytes, including (a) the specific markers and morphological characteristics, (b) the effects of A1/A2 astrocytes on the neurovascular unit, and (c) the molecular mechanisms involved in the phenotypic switch of astrocytes. Although many questions remain, a deeper understanding of different phenotypic astrocytes will eventually help us to explore effective strategies for neurological disorders by targeting astrocytes. • A1/A2 astrocytes and their specific markers are closely related to various CNS injuries and diseases. • A1/A2 astrocytes have diverse effects on the neurovascular unit in CNS injuries and diseases. • The local extracellular and intracellular signals regulate phenotypic switch of astrocytes. • Targeting A1/A2 astrocytes may be a potential strategy for most neurological disorders. [ABSTRACT FROM AUTHOR]

Uremia is a common syndrome that happens to nearly all end-stage kidney diseases, which profound have changes in human gene expressions, but the related pathways are poorly understood. Gene Ontology categories and Kyoto Encyclopedia of Genes and Genomes pathways enriched in the differentially expressed genes (DEGs) were analyzed by using clusterProfiler, org.Hs.eg.db, and Pathview, and protein–protein interaction (PPI) network was built by Cytoscape. We identified 3432 DEGs (including 3368 down- and 64 up-regulated genes), of which there were 52 different molecular functions, and 178 genes were identified as immune genes controlled by the four transcription factors (POU domain class 6 transcription factor 1 (POU6F1), interferon regulator factor 7 [IRF7], forkhead box D3 (FOXD3), and interferon-stimulated response element [ISRE]). In the gender research, no significant difference was observed. The top 15 proteins of 178 immune-related genes were identified with the highest degree in PPI network. The DEG analysis of uremia patients was expected to provide fundamental information to relieve pain and add years to their life. [ABSTRACT FROM AUTHOR]

Vitiligo (VIT) is caused by loss and degradation of functional epidermal melanocytes. Studies have indicated that melanocyte destruction may be associated with an imbalance between regulatory T cells (Treg cells) and effector T cells (Teff cells). The current study aimed to investigate the molecular mechanism through which Treg/Teff balance affects VIT pathogenesis. To explore this, peripheral blood mononuclear cells were isolated from patients with VIT and healthy individuals. The present study revealed that the proportions of CD4+ T cells, Treg cells and T helper 1 (Th1) cells were decreased in patients with VIT, but those of Teff cells (Th17 and Th22 cells) were increased; additionally, Foxp3 expression was decreased, but the expression levels of interferon-γ, interleukin (IL)-17A and IL-22 were increased. Furthermore, in patients with VIT, microRNA (miR)-21-5p expression was decreased, while that of STAT3 was increased. Further in vitro experiments in CD4+ T cells revealed that STAT3 was targeted by miR-21-5p. Functional analysis further indicated that miR-21-5p overexpression in Th17-polarized CD4+ T cells decreased the proportion of Teff cells and associated cytokines, such as IL-17A and IL-22, but increased the proportion of Treg cells and Foxp3. However, the effects of miR-21-5p overexpression were partly reversed by STAT3 overexpression. Increased apoptosis of melanocytes was detected after co-culture with Th17-polarized CD4+ T cells in the presence of a miR-21-5p mimic. However, this indirect effect of the miR-21-5p mimic on melanocytes was decreased via STAT3 overexpression. Therefore, miR-21-5p may protect melanocytes via targeting STAT3 and regulating Treg/Teff balance. The current findings may provide a possible treatment method for managing VIT. [ABSTRACT FROM AUTHOR]

Antioxidant status is considered as important factor in the pathogenesis of vitiligo. However, there are controversial findings about serum status of antioxidants in vitiligo patients. The purpose of this study was to systematically review the evidences comparing the serum levels of antioxidant vitamins and minerals between vitiligo patients and controls, and performing meta-analysis of the results. A comprehensive search was performed for studies comparing the serum status of antioxidant vitamins and minerals using following databases since inception up to 30 April 2020; PubMed, EMBASE, Scopus, and Web of Science. Data extraction was done by two independent reviewers. The data was pooled for serum level of each antioxidant comparing between vitiligo and control groups. Thirteen studies were included in this systematic review. The serum level of vitamin A, C, E, selenium, zinc and copper were compared between vitiligo patients and controls in these studies. Eleven studies including 570 vitiligo cases and 580 controls were included in the meta-analysis. Serum vitamin A and copper level in vitiligo patients were only evaluated in single studies and not included in meta-analysis. Based on fixed effect model, there were no statistical difference between two groups regarding serum vitamin C (OR = 1.17, 95 % CI, 0.74–1.84, P = 0.495), and vitamin E (OR = 0.61, 95 % CI, 0.30–1.25, P = 0.180). Higher serum zinc can decrease the risk of vitiligo based on sensitivity analysis of the results. (OR = 0.29, 95 % CI 0.15−0.54, P < 0.001). Higher serum selenium level significantly increased the risk of vitiligo (OR = 4.31, 95 % CI, 2.72–6.81, P < 0.001). Vitamin A was not significantly different in two reported groups (6.35 ± 1.53 vs 6.77 ± 1.46 μg/mL, P > 0.05). Copper was significantly higher in vitiligo patients compared to controls (129 ± 33 vs 99 ± 19 μg /100 mL, P = 0.002). The current meta-analysis of data on serum level of most studied antioxidants (vitamin C, vitamin E, zinc and selenium) in patients suffering vitiligo showed that higher serum selenium (OR = 4.31) and lower zinc level (OR = 0.29) can increased the risk of vitiligo. Potential mechanism associated with preventive effects of zinc and the depigmentation effect of selenium should be more elucidated in further studies. [ABSTRACT FROM AUTHOR]

Adversarial training has become the mainstream method to boost adversarial robustness of deep models. However, it often suffers from the trade-off dilemma, where the use of adversarial examples hurts the standard generalization of models on natural data. To study this phenomenon, we investigate it from the perspective of spatial attention. In brief, standard training typically encourages a model to conduct a comprehensive check to input space. But adversarial training often causes a model to overly concentrate on sparse spatial regions. This reduced tendency is beneficial to avoid adversarial accumulation but easily makes the model ignore abundant discriminative information, thereby resulting in weak generalization. To address this issue, this paper introduces an Attention-Enhanced Learning Framework (AELF) for robustness training. The main idea is to enable the model to inherit the attention pattern of standard pre-trained model through an embedding-level regularization. To be specific, given a teacher model built on natural examples, the embedding distribution of teacher model is used as a static constraint to regulate the embedding outputs of the objective model. This design is mainly supported with that the embedding feature of standard model is usually recognized as a rich semantic integration of input. For implementation, we present a simplified AELFs that can achieve the regularization with single cross entropy loss via the parameter initialization and parameter update strategy. This avoids the extra consistency comparison operation between embedding vectors. Experimental observations verify the rationality of our argument, and experimental results demonstrate that it can achieve remarkable improvements in generalization under the high-level robustness. [ABSTRACT FROM AUTHOR]