Zhejiang Gongshang University

About: Zhejiang Gongshang University is a education organization based out in Hangzhou, China. It is known for research contribution in the topics: Adsorption & Supply chain. The organization has 8258 authors who have published 7670 publications receiving 90296 citations. The organization is also known as: Zhèjiāng Gōngshāng Dàxué.

Design of Optimal Monitor-Based Supervisors for a Class of Petri Nets With Uncontrollable Transitions

Abstract: For a class of Petri nets whose uncontrollable influence subnets are forward synchronization and backward conflict-free nets, this paper proposes an algorithm to transform a given generalized mutual exclusion constraint (GMEC) into an optimal admissible one. Based on the proposed constraint transformation, a method is given to synthesize an optimal monitor-based supervisors. The proposed method utilizes an optimal monitor-based supervisor to enforce a GMEC containing infinite elements, which has not been seen in any prior research. Moreover, it has higher computational efficiency at the expense of application scope than some existing methods. An example is used to illustrate the application of the proposed method.

Fluorescent 3-hydroxy-4-pyridinone hexadentate iron chelators: intracellular distribution and the relevance to antimycobacterial properties.

Abstract: We report the synthesis and characterization of a fluorescent iron chelator (4), shown to be effective in inhibiting the growth of Mycobacterium avium in macrophages, together with the synthesis and characterization of two unsuccessful analogues selected to facilitate identification of the molecular properties responsible for the antimicrobial activity. Partition of the chelators in liposomes was investigated and the compounds were assessed with respect to uptake by macrophages, responsiveness to iron overload/iron deprivation and intracellular distribution by flow cytometry and confocal microscopy. The synthesis of the hexadentate chelators is based on a tetrahedral structure to which three bidentate 3-hydroxy-4-pyridinone chelating units are linked via amide bonds. The structure is synthetically versatile, allowing further addition of functional groups such as fluorophores. Here, we analyse the non-functionalized hexadentate unit (3) and the corresponding rhodamine B (4) and fluorescein (5) labelled chelators. The iron(III) stability constant was determined for 3 and the values log beta = 34.4 and pFe(3+) = 29.8 indicate an affinity for iron of the same order of magnitude as that of mycobacteria siderophores. Fluorescence properties in the presence of liposomes show that 4 strongly interacts with the lipid phase, whereas 5 does not. Such different behaviour may explain their distinct intracellular localization as revealed by confocal microscopy. The flow cytometry and confocal microscopy studies indicate that 4 is readily engulfed by macrophages and targeted to cytosol and vesicles of the endolysosomal continuum, whereas 5 is differentially distributed and only partially colocalizes with 4 after prolonged incubation. Differential distribution of the compounds is likely to account for their different efficacy against mycobacteria.

Characterization of dietary fiber from wheat bran (Triticum aestivum L.) and its effect on the digestion of surimi protein

Abstract: Dietary fiber is a class of polysaccharides that can not be digested by the gastrointestinal tract but have a significant physiological role. In this study, the insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) were obtained by enzymatic hydrolysis and lyophilization of wheat bran (Triticum aestivum L.). The physicochemical properties were to evaluated by laser diffraction, scanning electron microscopy, Fourier-transform infrared spectroscopy and X-ray diffraction. The results showed that the IDF was good at absorbing peanut oil (5.86 g/g), lard (9.63 g/g), cholesterol (4.11 mg/g in small intestine and 2.87 mg/g in stomach), sodium cholate (3.19 mg/g) and nitrite (100% at 105 min), while the SDF showed impressive DPPH, ABTS•+ and hydroxyl radical scavenging capacity. Finally, the surimi was fortified with IDF or SDF for in vitro protein digestion assay, and the physiological effects of dietary fiber resulted in a general reduction in digestibility with increased dosages of IDF and SDF. The functional properties of dietary fiber are potentially related with achieving healthy weight, making it a good additive in surimi products industry.