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Two-dimensional (2D) AMX2 compounds are a family of mixed ionic and electronic conductors (where A is a monovalent metal ion, M is a trivalent metal, and X is a chalcogen) that offer a fascinating platform to explore intrinsic coupled ionic-electronic properties. However, the synthesis of 2D AMX2 compounds remains challenging due to their multielement characteristics and various by-products. Here, we report a separated-precursor-supply chemical vapor deposition strategy to manipulate the chemical reactions and evaporation of precursors, facilitating the successful fabrication of 20 types of 2D AMX2 flakes. Notably, a 10.4 nm-thick AgCrS2 flake shows superionic behavior at room temperature, with an ionic conductivity of 192.8 mS/cm. Room temperature ferroelectricity and reconfigurable positive/negative photovoltaic currents have been observed in CuScS2 flakes. This study not only provides an effective approach for the synthesis of multielement 2D materials with unique properties, but also lays the foundation for the exploration of 2D AMX2 compounds in electronic, optoelectronic, and neuromorphic devices. 2D AMX2 compounds (where A is a monovalent metal ion, M is a trivalent metal, and X is a chalcogen) are a family of materials with coupled ionic-electronic properties. Here, the authors report a chemical vapor deposition strategy to fabricate 20 types of 2D AMX2 flakes, exhibiting superionic conductivity or room temperature ferroelectricity. [ABSTRACT FROM AUTHOR]

In this paper, we mainly study the asymptotic monotonicity of positive solutions for fractional parabolic equation on the right half space. First, a narrow region principle for antisymmetric functions in unbounded domains is obtained, in which we remarkably weaken the decay condition u → 0 at infinity and only assume its growth rate does not exceed | x | γ (0 < γ < 2 s ) compared with (Adv. Math. 377:107463, 2021). Then we obtain asymptotic monotonicity of positive solutions of fractional parabolic equation on R + N × (0 , ∞) . [ABSTRACT FROM AUTHOR]

Background: Vulvovaginal candidiasis (VVC) is a public health issue worldwide. Little is known of the optimal treatment of recurrent VVC (RVVC) has not been established. Objective: Through the in vitro antifungal susceptibility profiling of VVC isolates, we hope to foster significant improvements in the control and treatment of this disease. Methods: Candida isolates from VVC patients were collected from 12 hospitals in 10 cities across China. Species were identified by phenotype analysis and DNA sequencing. Species were identified by phenotype analysis and DNA sequencing. Susceptibilities to 11 drugs were determined by Clinical and Laboratory Standards Institute broth microdilution. Results: 543 strains were isolated from those VVC patients enrolled in this study, of which, 15.7% were from RVVC. The most commonly identified species was C. albicans (460, 84.71%), and the most commonly non-albicans Candida spp. (NAC) was C. glabrata (47, 8.66%). NAC also included C. Krusei, Meyerozyma Guillermondii, Meyerozyma Caribbica, C. Tropicalis, C. Parapsilosis, and C. Nivariensis. Most C. albicans isolates were susceptible to caspofungin (99.8%), followed by fluconazole (92%) and voriconazole (82.6%). The proportion of C. albicans strains with wild type (WT) MICs that were susceptible to amphotericin B and caspofungin were 98%, followed by posaconazole at 95%, itraconazole at 86%, fluconazole at 74% and voriconazole at 54%. The fluconazole MICs for C. albicans were lower than those for NAC (P < 0.05), while the itraconazole MICs showing no significant difference (P > 0.05). The susceptible rate of uncomplicated VVC to fluconazole was 92%. The proportion of WT strains to fluconazole in RVVC was much lower than that in other types of VVC (67 vs. 77%, P < 0.05). However, the proportions of WT strains to itraconazole in RVVC was over 85%, which was much higher than that to fluconazole (87 vs. 67%, P < 0.05). Conclusions: C. albicans was still the predominant pathogen for VVC in China, while C. glabrata was the main species in NAC. Fluconazole could still be used as an empirical treatment for uncomplicated VVC. However, fluconazole may not be the first choice for the therapy of RVVC. In such cases, itraconazole appears to be the more appropriate treatment. As for VVC caused by NAC, nonfluconazole drugs, such as itraconazole, may be a good choice. [ABSTRACT FROM AUTHOR]

Silver nanoplates were for the first time synthesized on electrospun chitosan/polyethylene oxide (CS/PEO) fibers via tollens reaction. Ag nanoplates/CS/PEO fibers were used as the SERS-active substrates for quantitative evaluation of 2-naphthylthiol, with an enhancement factor (1.41 ± 0.07) × 106. The SERS-active substrates are flexible, stable, and easy for transportion and preservation, and act as the SERS platform for sensitive detection of the target. Thiram and thiabendazole as the representatives of pesticide residues were identified and detected by the Ag nanoplates/CS/PEO fibers, exhibiting linear response ranges from 10−11 to 10−7 M with a detection limit of 10−11 M. The Ag nanoplates/CS/PEO fibers meet the requirement of thiram detection in practical samples, such as apple, pear, tomato, and cucumber juices. The strategy revealed the feasibility of fabrication of Ag nanoplates on electrospun fibers via tollens reaction and SERS sensing of pesticides in real samples. [ABSTRACT FROM AUTHOR]

Purpose: To identify the genetic cause of patients with primary ciliary dyskinesia (PCD) and male infertility from two unrelated Han Chinese families. Methods: We conducted whole-exome sequencing of three individuals with PCD and male infertility from two unrelated Chinese families, and performed a targeted look-up for DNAAF6 variants in our previously reported cohort of 442 individuals (219 with isolated oligoasthenospermia and 223 fertile controls). Ultrastructural and immunostaining analyses of patients' spermatozoa were performed. The pathogenicity of the variants was validated using patient's spermatozoa and HEK293T cells. Intracytoplasmic sperm injection (ICSI) treatment was conducted in two patients. Results: We identified one novel hemizygous frameshift variant (NM_173494, c.319_329del: p.R107fs) of DNAAF6 gene (previously named PIH1D3) in family 1 and one novel hemizygous missense variant (c.290G>T: p.G97V) in family 2. No hemizygous deleterious variants in DNAAF6 were detected in the control cohort of 442 individuals. Ultrastructural and immunostaining analyses of patients' spermatozoa showed the absence of outer and inner dynein arms in sperm flagella. Both variants were proven to lead to DNAAF6 protein degradation in HEK293T cells. Both patients carrying DNAAF6 variants underwent one ICSI cycle and delivered one healthy child each. Conclusion: We identified novel DNAAF6 variants causing male infertility and PCD in Han Chinese patients. This finding extended the spectrum of variants in DNAAF6 and revealed new light on the impact of DNAAF6 variants in sperm flagella. [ABSTRACT FROM AUTHOR]

To predict and analyze the municipal solid waste (MSW) pyrolysis and gasification process in an updraft fixed bed more veritably and appropriately, numerical modeling based on Gibbs energy minimization was executed using the Aspen plus software. The RYield module was combined with the RGibbs module to describe the pyrolysis section, while the RGibbs module was used for the gasification section individually. The proposed model was used to forecast and analyze the target performance parameters including syngas composition, lower heating value (LHV) and carbon conversion rate under different conditions of the gasification temperatures, and ratios and types of gasifying agents. The results indicate that there is a good agreement between the experimental data and the simulated data obtained using this model. The predicted optimum gasification temperature is approximately 750°C, and the best ratio of water vapor as gasifying agent is around 0.4. The mixture of flue gas and water vapor has an economical and recycled prospect among four commonly used gasifying agents. [ABSTRACT FROM AUTHOR]

Redox-responsive surfactant based on selenium atom has recently attracted considerable interests. Herein, we have designed and synthesized three selenium-containing cationic surfactants with different headgroups, including N-(benzylselanyl-undecyl)-N,N,N-trimethyl ammonium bromide (BSeTAB)/pyridinium bromide (BSePyB)/methylpyrrolidinium bromide (BSeMPB). Their micellization in dilute solution was investigated by surface tension and conductivity, and was related to redox-induced change in molecular structure. Both 1H NMR and ESI-MS spectra demonstrated that selenide in the reduced form is transformed into selenoxide after oxidation with H2O2, whatever the headgroup is. The formation of selenoxide not only increases the hydrophilicity of surfactant, resulting in a more negative ∆Gadso, larger cmc, cmc/C20 ratio, and Gmin, compared to the reduced forms, but also provides a new polar headgroup, making it behave like bola-type structure and enhancing the hydrophilicity. The relatively smaller cmc, larger cmc/C20 ratio, and more negative ∆Gmo value all revealed that the pyridinium or pyrrolidinium polar headgroup is more favorable for the micelle formation than the trimethylammonium group. The thermodynamic parameters showed that the micellization is transformed from entropy-driven mode to enthalpy-driven mode with increasing temperature and the transition temperature at which ∆Hmo equals to −T∆Smo is lowest for BSeMPB, and highest for BSePyB. [ABSTRACT FROM AUTHOR]

The design and synthesis of highly active non-noble metal oxide catalysts, such as transition- and rare-earth-metal oxides, have attracted significant attention because of their high efficiency and low cost and the resultant potential applications for the degradation of volatile organic compounds (VOCs). The structure-activity relationships have been well-studied and used to facilitate design of the structure and composition of highly active catalysts. Recently, non-noble metal oxides with porous structures have been used as catalysts for deep oxidation of VOCs, such as aromatic hydrocarbons, aliphatic compounds, aldehydes, and alcohols, with comparable activities to their noble metal counterparts. This review summarizes the growing literature regarding the use of porous metal oxides for the catalytic removal of VOCs, with emphasis on design of the composition and structure and typical synthetic technologies. [ABSTRACT FROM AUTHOR]

The effects of allophane (ALL) as a synergistic agent on the flame retardancy and thermal stability of intumescent flame-retardant (IFR) polypropylene composites were studied by limiting oxygen index (LOI), UL-94 test, cone calorimeter test (CONE) and thermogravimetric analysis. The incorporation of ALL led to enhanced thermal stability, LOI value and UL-94 ratings. CONE tests indicated that heat release rate, peak rate of heat release, smoke production rate, total smoke production and mass loss values of PP/IFR/ALL sample were much lower than those of PP/IFR and pure PP samples. Fourier transform infrared spectrometry result proved the presence of silicoaluminophosphate which can act as a catalytic agent to enhance the oxidative dehydration crosslinking charring process. Scanning electron microscopy and Raman spectra observation demonstrated that ALL could promote forming homogenous and compact char layer. The mechanical properties of PP composites were also improved by the loading of ALL. [ABSTRACT FROM AUTHOR]

Let α and s be real numbers satisfying 0< s< α< n. We are concerned with the integral equation where $\frac{n-s}{n-\alpha}< p< \alpha^{*}(s)-1$ with $\alpha^{*}(s)=\frac{2(n-s)}{n-\alpha}$. We prove the nonexistence of positive solutions for the equation and establish the equivalence between the above integral equation and the following partial differential equation [ABSTRACT FROM AUTHOR]

A series of Mn-Co mixed oxide nanorods with homogeneous worm-like pores were facilely prepared by a sol-gel chelating method. With incorporating Mn into CoO, the formation of solid solution with spinel structure inhibits the growth of nanoparticles which is benefit to keep smaller crystal size and higher surface area. XPS and H-TPR results indicate that there are more high manganese valence (Mn and Mn) and adsorbed oxygen species as well as low-temperature reducibility for the mixed oxide catalysts, as a result of the strong synergistic effect between Mn and Co species in solid solution, which will play a key role in catalytic activity. The as-prepared catalysts were used for catalytic deep oxidation of benzene which is a typical carcinogenic VOC. The catalytic activities over the mixed oxides with varied mole ratio are much higher than that on the single MnO or CoO. The MnCo sample showed the best activity with T for benzene conversions into CO were low to 237 °C at a high space velocity of 120,000 mL g h. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

ZnO and Sn-, Ga- and Mn-doped ZnO nanoparticles were prepared by a coprecipitation method, and characterized by scanning electron microscopy (SEM), energy dispersive spectra (EDS), X-ray diffraction (XRD) and Raman spectra. The gas sensing properties were studied using formaldehyde, relative humidity, NH, toluene and CO as the probes. The results show that all particles have wurtzite ZnO phase, though Sn-ZnO has a relatively smaller particle (and crystallite) size than the other three samples. Gas sensing property tests reveal that the temperature where the gas sensing maximum is gained ( T) is changed by different dopants: Sn-ZnO and Mn-ZnO have relatively lower T (∼100°C lower) compared with that of pure ZnO, while Ga-ZnO has the same T as pure ZnO except in CO sensing. Thermoluminescence (TL) spectra were used to investigate the mechanism of T change. The peak positions of Ga-ZnO and ZnO are the same at 300-350°C, while that of Sn-ZnO shifts to 250-300°C, which might contribute to the same T of Ga-ZnO and pure ZnO and relatively lower T of Sn-ZnO. In the case of Mn-ZnO, the luminescence emission is evidently limited by its black color. [ABSTRACT FROM AUTHOR]

Polyacrylonitrile fibers with and without magnetic nanoparticles (Fe3O4 NPs) were prepared by electrospinning. The pure polyacrylonitrile (PAN) fibers and the composited polyacrylonitrile (PAN/Fe3O4) fibers were studied with respect to their capability for enrichment of glycoproteins. Specifically, the glycoproteins ovalbumin (OB) and transferrin (Trf) were studied and compared to the non-glycoproteins bovine serum albumin and lysozyme. Following adsorption and subsequent protein elution with 0.1 wt% of CTAB solution, the glycoproteins were analyzed by SDS polyacrylamide gel electrophoresis. The strong interaction between PAN or PAN/Fe3O4 fibers and glycoproteins is attributed to the synergistic effects of hydrophilic and hydrogen bond interactions. The PAN/Fe3O4 fibers have an attractive additional feature of allowing magnetic separation. The PAN and PAN/Fe3O4 fibers have a high adsorption capacity toward OB and Trf. The treated PAN/Fe3O4 fibers display good selectivity, fast adsorption kinetics, and were applied to extractions of mixed protein samples. The detection limits of OB and Trf are 0.32 and 0.22 μg·mL−1, respectively. The PAN/Fe3O4 fibers offered an alternative solution for adsorption of glycoproteins from biological samples. [ABSTRACT FROM AUTHOR]