60 research outputs found
An Improved Predefined-time Adaptive Neural Control Approach for Nonlinear Multiagent Systems
Synchronous MDADT-Based Fuzzy Adaptive Tracking Control for Switched Multiagent Systems via Modified Self-Triggered Mechanism
In this paper, a self-triggered fuzzy adaptive switched control strategy is proposed to address the synchronous tracking issue in switched stochastic multiagent systems (MASs) based on mode-dependent average dwell-time (MDADT) method. Firstly, a synchronous slow switching mechanism is considered in switched stochastic MASs and realized through a class of designed switching signals under MDADT property. By utilizing the information of both specific agents under switching dynamics and observers with switching features, the synchronous switching signals are designed, which reduces the design complexity. Then, a switched state observer via a switching-related output mask is proposed. The information of agents and their preserved neighbors is utilized to construct the observer and the observation performance of states is improved. Moreover, a modified self- triggered mechanism is designed to improve control performance via proposing auxiliary function. Finally, by analysing the re- lationship between the synchronous switching problem and the different switching features of the followers, the synchronous slow switching mechanism based on MDADT is obtained. Meanwhile, the designed self-triggered controller can guarantee that all signals of the closed-loop system are ultimately bounded under the switching signals. The effectiveness of the designed control method can be verified by some simulation results
Author Correction: The disease resistance protein SNC1 represses the biogenesis of microRNAs and phased siRNAs.
The original version of this Article contained an error in the spelling of the author Beixin Mo, which was incorrectly given as Beixing Mo. This has now been corrected in both the PDF and HTML versions of the Article
Critical role of FGF21 in diabetic kidney disease: from energy metabolism to innate immunity
Diabetic kidney disease (DKD) stands as the predominant cause of chronic kidney disease (CKD) on a global scale, with its incidence witnessing a consistent annual rise, thereby imposing a substantial burden on public health. The pathogenesis of DKD is primarily rooted in metabolic disorders and inflammation. Recent years have seen a surge in studies highlighting the regulatory impact of energy metabolism on innate immunity, forging a significant area of research interest. Within this context, fibroblast growth factor 21 (FGF21), recognized as an energy metabolism regulator, assumes a pivotal role. Beyond its role in maintaining glucose and lipid metabolism homeostasis, FGF21 exerts regulatory influence on innate immunity, concurrently inhibiting inflammation and fibrosis. Serving as a nexus between energy metabolism and innate immunity, FGF21 has evolved into a therapeutic target for diabetes, nonalcoholic steatohepatitis, and cardiovascular diseases. While the relationship between FGF21 and DKD has garnered increased attention in recent studies, a comprehensive exploration of this association has yet to be systematically addressed. This paper seeks to fill this gap by summarizing the mechanisms through which FGF21 operates in DKD, encompassing facets of energy metabolism and innate immunity. Additionally, we aim to assess the diagnostic and prognostic value of FGF21 in DKD and explore its potential role as a treatment modality for the condition
Homozygous p.Ser267Phe in SLC10A1 is associated with a new type of hypercholanemia and implications for personalized medicine.
SLC10A1 codes for the sodium-taurocholate cotransporting polypeptide (NTCP), which is a hepatocellular transporter for bile acids (BAs) and the receptor for hepatitis B and D viruses. NTCP is also a target of multiple drugs. We aimed to evaluate the medical consequences of the loss of function mutation p.Ser267Phe in SLC10A1. We identified eight individuals with homozygous p.Ser267Phe mutation in SLC10A1 and followed up for 8-90 months. We compared their total serum BAs and 6 species of BAs with 170 wild-type and 107 heterozygous healthy individuals. We performed in-depth medical examinations and exome sequencing in the homozygous individuals. All homozygous individuals had persistent hypercholanemia (P = 5.8 × 10-29). Exome sequencing excluded the involvement of other BA metabolism-associated genes in the hypercholanemia. Although asymptomatic, all individuals had low vitamin D levels. Of six adults that were subjected to bone mineral density analysis, three presented with osteoporosis/osteopenia. Sex hormones and blood lipids were deviated in all subjects. Homozygosity of p.Ser267Phe in SLC10A1 is associated with asymptomatic hypercholanemia. Individuals with homozygous p.Ser267Phe in SLC10A1 are prone to vitamin D deficiency, deviated sex hormones and blood lipids. Surveillance of these parameters may also be needed in patients treated with drugs targeting NTCP.This project is supported by the National Natural Science Foundation of China (31471193, 81570539, 81370535, 91331204 and 31525014). S.X. acknowledges financial support from the Strategic Priority Research Program (XDB13040100) and Key Research Program of Frontier Sciences (QYZDJ-SSW-SYS009) of the Chinese Academy of Sciences (CAS)
Numerical Analysis of the Diaphragm Valve Throttling Characteristics
The throttling characteristics of the diaphragm valve are numerically studied in this paper. Firstly, the diaphragm deformation performance is analyzed by a finite element method, while the upper boundary morphology of the internal flow field under different valve openings was obtained. Then the two-dimensional simulation of the weir diaphragm valve flow field is carried out in order to explore the optimal design of flow path profile. The study shows that the throttling characteristics can be improved by flatting the ridge side wall, widening the top of the ridge and gently flatting the internal protruding of the flow path. In addition, using the local grid encryption techniques based on velocity gradient adaptive and y+ adaptive can improve the accuracy of simulation results. Finally, a cavitation two-phase flow simulation is carried out. The results show that cavitation may occur below 50% opening of diaphragm valve in ultra-pure water system, which becomes more intense with the increase of inlet pressure and even leading to flow saturation on the micro-orifice state
Charge-Sensitive Optical Detection of Binding Kinetics between Phage-Displayed Peptide Ligands and Protein Targets
Phage display technology has been a powerful tool in peptide drug development. However, the supremacy of phage display-based peptide drug discovery is plagued by the follow-up process of peptides synthesis, which is costly and time consuming, but is necessary for the accurate measurement of binding kinetics in order to properly triage the best peptide leads during the affinity maturation stages. A sensitive technology is needed for directly measuring the binding kinetics of peptides on phages to reduce the time and cost of the entire process. Here, we show the capability of a charge-sensitive optical detection (CSOD) method for the direct quantification of binding kinetics of phage-displayed peptides to their target protein, using whole phages. We anticipate CSOD will contribute to streamline the process of phage display-based drug discovery
Effect of chlorine on performance of Pd catalysts prepared via colloidal immobilization
This contribution shows the effect of residual chlorine on the catalytic performance of a Pd-based catalyst in the hydrogenation of nitrite for cleaning of drinking water. The catalyst was prepared via immobilization a colloidal Pd nanoparticles using activated carbon as support. Different amount of hydrochloric acid (HCl) was added to immobilize the Pd colloid on the carbon support, facilitating the removal of the residual stabilizer, polyvinyl alcohol (PVA), from the surface of the Pd nanoparticles (NPs). The catalysts were characterized by TEM, CO-chemisorption, XRF, N2 physisorption, UV-vis spectroscopy, and XPS. The activity and selectivity of the catalysts were measured for nitrite hydrogenation in semi-batch operation. The results show that PVA can be removed completely at pH below 2. The residual chlorine on the catalysts can be removed by reduction in H2/N2 at a mild temperature, i.e. 200°C, regardless the amount of HCl used. Nevertheless, high concentration of HCl during immobilization (pH 1) causes partial Pd re-dissolution according to UV-vis spectroscopy, resulting in formation of highly dispersed Pd clusters that could not be detected with TEM. Reduction of this catalyst with high chlorine content in H2 at 200°C is resulting in formation of relatively large Pd particles via sintering. Without pre-reduction at 200°C, residual chlorine can also be removed almost completely during the hydrogenation reaction at room temperature. The activity of the Pd catalyst is insensitive to the chlorine concentration below 30μmolL-1 in the aqueous reaction mixture. Interestingly, the selectivity to N2 is improved by adding chlorine to the reaction mixture, independent of the way chlorine is added, i.e. via the catalyst or added directly to the reaction solution
- …