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This paper considers a class of multi-agent distributed convex optimization with a common set of constraints and provides several continuous-time neurodynamic approaches. In problem transformation, l 1 and l 2 penalty methods are used respectively to cast the linear consensus constraint into the objective function, which avoids introducing auxiliary variables and only involves information exchange among primal variables in the process of solving the problem. For nonsmooth cost functions, two differential inclusions with projection operator are proposed. Without convexity of the differential inclusions, the asymptotic behavior and convergence properties are explored. For smooth cost functions, by harnessing the smoothness of l 2 penalty function, finite- and fixed-time convergent algorithms are provided via a specifically designed average consensus estimator. Finally, several numerical examples in the multi-agent simulation environment are conducted to illustrate the effectiveness of the proposed neurodynamic approaches. [ABSTRACT FROM AUTHOR]

Under the development trend of large-size antennas, the demand for modular expansion of synthetic aperture radar antennas is increasing, and the connection mechanism is an important part of the modular expansion. This paper designed and studied the connection mechanism between the basic units of the planar deployable antenna mechanism. Firstly, for the basic deployable units of a new type of planar deployable antenna spatial support mechanism proposed previously by the author, the connection mechanism between the basic units was synthesized, and a series of feasible planar deployable mechanism configurations were obtained. Meanwhile, a spatial support mechanism for planar deployable antennas with scissor was optimally constructed by analysis. Through finite element comparative analysis, it was found that the mechanism improves the stiffness and reduces the maximum deformation. Then, scale optimization was performed by using the control variable method. Finally, the prototype was developed, and experimental research was conducted to verify the feasibility of the mechanism. The spatial support mechanism of the planar deployable antenna with scissor proposed in this paper improves the reliability, stiffness, modal, and other related properties of the unfolding process. Therefore, it has broad application prospects in the field of aerospace deployable antennas. • Propose a method to design the connection mechanism between the basic deployable units. • Design a spatial support mechanism for planar deployable antenna without P joints. • Compare the stiffness of the new mechanism and the previous one. • Develop a prototype of the proposed support mechanism and validate the motion principle. [ABSTRACT FROM AUTHOR]

Adult mammary stem cells (aMaSCs) are vital to tissue expansion and remodeling during the process of postnatal mammary development. The protein C receptor (Procr) is one of the well-identified surface markers of multipotent aMaSCs. However, an understanding of the regulatory mechanisms governing Procr's protein stability remains incomplete. In this study, we identified Glycoprotein m6a (Gpm6a) as a critical protein for aMaSC activity modulation by using the Gpm6a knockout mouse model. Interestingly, we determined that Gpm6a depletion results in a reduction of Procr protein stability. Mechanistically, Gpm6a regulates Procr protein stability by mediating the formation of lipid rafts, a process requiring Zdhhc1 and Zdhhc2 to palmitate Gpm6a at Cys17,18 and Cys246 sites. Our findings highlight an important mechanism involving Zdhhc1- and Zdhhc2-mediated Gpm6a palmitoylation for the regulation of Procr stability, aMaSC activity, and postnatal mammary development. [Display omitted] • Loss of Gpm6a hinders mammary gland development and reduces the activity of aMaSCs • Gpm6a deficiency disrupts Procr protein stability by inhibiting the formation of lipid rafts • Palmitoylation of Gpm6a, mediated by Zdhhc1 and Zdhhc2, is crucial for the aMaSC activity Chen et al. demonstrate that Gpm6a deficiency reduces the activity of adult MaSCs. Gpm6a regulates the stability of the Procr protein by mediating the formation of lipid rafts. The palmitoylation of Gpm6a, facilitated by Zdhhc1 and Zdhhc2, is essential for Procr protein stability and adult MaSC activity. [ABSTRACT FROM AUTHOR]

In this paper, a novel spatial support mechanism for planar deployable antennas is designed based on the motion principle of planar deployable antennas and the spatial mechanism theory. The composition principle of the novel mechanism and its geometric characteristics are analyzed, and its degrees of freedom are calculated based on the constraint topological diagram. Subsequently, kinematic analysis is conducted, and the angular velocity, linear velocity, and linear acceleration of each component in the mechanism are calculated. Then, numerical calculation and simulation are performed to verify the correctness of the theoretical analysis results. The performance analysis of the spatial support mechanism is completed. A prototype of the proposed support mechanism is developed and tested to validate the feasibility of the mechanism principle. The present work can provide reference for the design and engineering application of this type of mechanisms. • 1.Propose a novel support mechanism for planar deployable antennas. • 2.Analyze the DOFs, kinematics, dynamics based on the constraint topological diagram. • 3.Develop a prototype of the proposed support mechanism and validate the motion principle. [ABSTRACT FROM AUTHOR]

Pesticide residues in grapes could be transferred to fermentation system during the wine-making process, which may interfere the normal proliferation of Saccharomyces cerevisiae and subsequently affect the safety and quality of wine products. However, the interaction between pesticides and Saccharomyces cerevisiae is still poorly understood. Herein, the fate, distribution and interaction effect with Saccharomyces cerevisiae of five commonly-used pesticides during the wine-making process were evaluated. The five pesticides exerted varied inhibition on the proliferation of Saccharomyces cerevisiae , and the order of inhibition intensity was difenoconazole > tebuconazole > pyraclostrobin > azoxystrobin > thiamethoxam. Compared with the other three pesticides, triazole fungicides difenoconazole and tebuconazole showed stronger inhibition and played a major role in binary exposure. The mode of action, lipophilicity and exposure concentration were important factors in the inhibition of pesticides. Saccharomyces cerevisiae had no obvious impacts on the degradation of target pesticides in the simulated fermentation experiment. However, the levels of target pesticides and their metabolite were significantly reduced during the wine-making process, with the processing factors ranged from 0.030 to 0.236 (or 0.032 to 0.257) during spontaneous (or inoculated) wine-making process. As a result, these pesticides were significantly enriched in the pomace and lees, and showed a positive correlation (R2 ≥ 0.536, n = 12, P < 0.05) between the hydrophobicity of pesticides and distribution coefficients in the solid-liquid distribution system. The findings provide important information for rational selection of pesticides on wine grapes and facilitate more accurate risk assessments of pesticides for grape processing products. [Display omitted] • Difenoconazole and tebuconazole strongly inhibited on Saccharomyces cerevisiae. • Action mode, lipophilicity and concentration were key factors in inhibition of pesticide. • Five pesticide residues were obviously reduced in wine after wine-making process. • Lipophilic pesticides tended to be enriched in the pomace and lees. [ABSTRACT FROM AUTHOR]

For the selective catalytic reduction of NO x with NH 3 (NH 3 -SCR) reaction, how to precisely adjust the reducibility and surface acidity over SCR catalysts remains a fundamental challenge. Here, a very facile and effective way, the addition of WO x species using an incipient wetness impregnation method, to balance the redox and acidic properties of CeO x for optimizing its SCR performance was proposed. Especially, nanopolyhedron CeO x with predominately exposed (111) facet was prepared as the support of W y Ce catalysts. As an effective surface modifier, the WO x species could not only suppress the over-oxidation of NH 3 over CeO x by partially covering oxygen vacancies, but also supply abundant Brønsted and Lewis acid sites, which stemmed from W O, W O W, Ce O W bonds and electronically deficient unsaturated Cen+, Wn+ cations, respectively. As a result, the SCR activity and N 2 selectivity of W y Ce catalysts were significantly improved at the same time, through the balance between the redox and acidic properties. The above results might open a new avenue for the design and preparation of more efficient SCR catalysts. [Display omitted] • The role of surface oxygen vacancies on W y Ce catalysts was illustrated in detail. • The WO x species on W y Ce catalysts could simultaneously adjust their redox and acidic properties. • The type of acid sites stemmed from WO x species over W y Ce catalysts was precisely distinguished. • The relationship of balance between redox and acidic properties over W y Ce catalysts was discussed thoroughly. [ABSTRACT FROM AUTHOR]

Nitrogen-doped carbons (NC) and carbon nitride (C 3 N 4) belong to the two fundamental pillars of functionalized carbon materials that have broad applications in different fields. The synthesis of NC and C 3 N 4 often starts from different precursors, and a general approach that can offer both architectures is still highly sought. Herein, a facile Triton X-100-assisted copolymerization-carbonization strategy is reported to fulfill this task. By moderating the weight ratios of Triton X-100 and several conventional precursors of C 3 N 4 (e.g., dicyandiamide, urea, and cyanamide), a series of both types of N-functionalized carbons with controllable N dopants is successfully afforded. The yielded solids transform from graphitic C 3 N 4 with low surface areas to porous NC when the weight ratio reaches the critical values. This phenomenon might be attributed to the intensified copolymerization between the intermediates of both starting precursors during the carbonization, resulting in increased oxygen content and decreased N:C ratio in the products. Both the bulk and activated carbon-supported materials are then designed and used as metal-free catalysts in the dehydrochlorination of ethylene dichloride, a key reaction in polyvinyl chloride manufacture. It is found that NC is significantly more active than C 3 N 4 , but the corresponding supported catalysts exhibit an opposing trend. The structure-activity correlations suggest both the number of different N defects and the surface areas might play key roles in determining the dehydrochlorination chemistry. Tailor synthesis of C 3 N 4 and N-doped carbons with controllable N defects was enabled by a newly developed approach through co-pyrolysis of Triton X-100 and conventional C 3 N 4 precursors. [Display omitted] [ABSTRACT FROM AUTHOR]

• A fluorescent sensor based on S-CQDs was constructed to detect pirimicarb. • A green deep eutectic solvent was synthesized to extract pirimicarb. • S-CQDs had vast negative charges as the fluorescence probe. • Electrostatic interactions led to fluorescence quenching of S-CQDs. • The proposed extraction and detection strategy has prospects in food analysis. A novel deep eutectic solvent-based extraction and sulfur-doped carbon quantum dots (S-CQDs) serving as fluorescence probes to detect pirimicarb in cereals were established. The deep eutectic solvent was synthesized using choline chloride and butanediol, achieving direct and efficient extraction of pirimicarb residue in the cereals. The fluorescence quenching of S-CQDs was caused by the electrostatic interaction between the negatively charged S-CQDs and positively charged thiocholine, which was the hydrolysate of acetylthiocholine. The fluorescence of S-CQDs was enhanced as the activity of acetylcholinesterase (AChE) was inhibited by pirimicarb, achieving the detection of pirimicarb in the cereal samples. The limit of detection (LOD) was 0.006 μg mL−1. The recovery ranged from 96.6% to 108.2%. This extraction and detection method of pirimicarb based on an environmentally friendly DES and S-CQD fluorescent sensor maintains good stability and convenience, offering a promising strategy for extracting and testing harmful substances in food samples. [ABSTRACT FROM AUTHOR]