Abstract
Metabolite alteration has been associated with the pathogenesis of inflammatory bowel disease (IBD), including colitis. Mannose, a natural bioactive monosaccharide that is involved in ...metabolism and synthesis of glycoproteins, exhibits anti-inflammatory and anti-oxidative activities. We show here that the circulating level of mannose is increased in patients with IBD and mice with experimental colitis. Mannose treatment attenuates intestinal barrier damage in two mouse colitis models, dextran sodium sulfate (DSS)-induced colitis and spontaneous colitis in
IL-10
-deficient mice. We demonstrate that mannose treatment enhanced lysosomal integrity and limited the release of cathepsin B, preventing mitochondrial dysfunction and myosin light chain kinase (MLCK)-induced tight junction disruption in the context of intestinal epithelial damage. Mannose exerts a synergistic therapeutic effect with mesalamine on mouse colitis. Cumulatively, the results indicate that mannose supplementation may be an optional approach to the treatment of colitis and other diseases associated with intestinal barrier dysfunction.
In order to improve the inherent drawbacks of particle swarm optimization (PSO), an effective informed adaptive PSO (EIA-PSO) algorithm that has better equilibrium characteristic between global ...search and local search is proposed. In this paper, an electrochemical-based proton exchange membrane fuel cell (PEMFC) mechanism model suitable for engineering optimization is developed, and a parameter-identification-technique-based EIA-PSO for this mechanism model is presented. In order to verify the validity of the advanced method, comparisons between experimental data and simulation data are carried out. The results demonstrate that EIA-PSO can make the mechanism model with identified parameters fit the experimental data with higher precision even in the presence of measurement noise. Therefore, EIA-PSO is an optional effective technique for identifying the parameters of the PEMFC mechanism model.
In this paper, we investigate the problem of stabilization for sampled-data fuzzy systems under variable sampling. A novel Lyapunov-Krasovskii functional (LKF) is defined to capture the ...characteristic of sampled-data systems, and an improved input delay approach is proposed. By the use of an appropriate enlargement scheme, new stability and stabilization criteria are obtained in terms of linear matrix inequalities (LMIs). Compared with the existing results, the newly obtained ones contain less conservatism. Some illustrative examples are given to show the effectiveness of the proposed method and the significant improvement on the existing results.
This technical note is concerned with the simultaneous stabilization and robust performance control for a class of polynomial nonlinear systems. Building on the tenets of state-dependent polynomial ...Lyapunov functions, we present sufficient conditions for simultaneous stabilization with and without Hinfin performance. These conditions can be verified by the recently developed sum of squares technique which essentially solves a linear matrix inequality feasibility problem.
Xanthones are secondary metabolites found in plants, fungi, lichens, and bacteria from a variety of families and genera, with the majority found in the Gentianaceae, Polygalaceae, and Clusiaceae. ...They have a diverse range of bioactivities, including anti-oxidant, anti-bacterial, anti-malarial, anti-tuberculosis, and cytotoxic properties. Xanthone glucosides are a significant branch of xanthones. After glycosylation, xanthones may have improved characteristics (such as solubility and pharmacological activity). Currently, no critical review of xanthone glucosides has been published. A literature survey including reports of naturally occurring xanthone glucosides is included in this review. The isolation, structure, bioactivity, and synthesis of these compounds were all explored in depth.
This paper proposes a precise real-time wind speed estimation method and sensorless control for variable-speed variable-pitch wind turbine power generation system (WTPGS). The wind speed estimation ...is realized by a nonlinear input–output mapping extreme learning machine (ELM). A specific design characteristic of the wind turbine is used for improving the mapping accuracy with considering the variable pitch angle. Moreover, since the design is independent of the environmental air density, the proposed ELM wind speed estimation method is robust to the air density variations. The estimated wind speed is then used to determine the optimal rotational speed command for maximum power point tracking. A fast and effective ELM mapping based pitch controller is proposed too when the WTPGS operates in its high wind speed region. The ELM pitch controller can act much faster and more precise than conventional pitch controllers. Furthermore, the complicated design precess for the parameters of conventional pitch controllers will be avoided in the proposed method. The effectiveness of the proposed methods are verified both by simulations and experiments on a WTPGS installed with Permanent Magnet Synchronous Generator (PMSG).
This paper investigates frequency-domain properties of reset systems with arbitrary reset matrices and their application in disturbance rejection. First, we investigate the sinusoid input response of ...a reset system. Then, through calculating the describing function, we reveal how the reset matrix affects the frequency-domain properties of the reset system. At last, we generalize the reset phase-lead controller to the nonzero reset matrix case. As an application, the proposed reset phase-lead controller is applied to compensate for the phase lag caused by a narrow band compensator for midfrequency disturbance in hard-disk-drive systems. Simulation results show that the proposed control scheme can enhance the midfrequency disturbance attenuation without degrading stability.
•This paper presents the first reported ACB terminal unit model.•The model encapsulates mechanical and thermal aspects.•A compromise is made between underlying physics and suitability for ...applications.•The model is obtained under the unique condition of ACB.•The model is accurate and robustness.
This paper proposes a hybrid dynamic model of active chilled beam (ACB) terminal unit. The model encapsulates mechanical and thermal aspects of the confined air jet and the cooling coil contained in the terminal unit and could be divided into two sub-models respectively. The models for the primary air, secondary air and mixing of them are together taken as the confined air jet sub-model. Another sub-model is the heat transfer description of the cooling coil. The model is kept simple and practical, avoiding sophisticated jet flow theories as well as heat transfer theories. Thus, in deriving the model using first principles and estimating it experimentally, a reasonable compromise is made between capturing exact underlying physics and suitability for engineering applications. Supported by experimental results from a pilot plant, unknown model parameters are identified by either a linear or nonlinear least-squares method. It is shown that static and dynamic performances of the model are satisfied, which reflect the effectiveness of this hybrid modeling technique as well. The model developed in this work is expected to have wide control and optimization applications.
This paper proposes a recursive delta-operator-based subspace identification method with fixed data size. The majority of existing subspace identification methods are constrained to discrete-time ...systems because of the disparity in Hankel matrices. Additionally, due to the storage cost, LQ-factorization and singular value decomposition in identification methods are best suited for batch processing rather than online identification. The continuous-time systems are transformed into state space models based on the delta-operator to address these issues. These models approach the original systems when the sampling interval approaches zero. The size of the data matrices is fixed to reduce the computing load. By fading the impact of past data on future data, the amount of data storage can be decreased. The effectiveness of the proposed method is illustrated by the continuous stirred tank reactor system.
This paper aims to study phospholipid (PL) profiling of muscle from Ctenopharyngodon idellus during room-temperature storage for 72 h by direct-infusion electrospray ionization tandem mass ...spectrometry (ESI–MS/MS). Five classes of PLs, including phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylserine (PS), and sphingomyelin (SM), were analyzed. At least 110 molecular species of PLs were identified, including 32 species of PC, 34 species of PE, 24 species of PS, 18 species of PI, and 2 species of SM. The result showed that oxidation and hydrolysis are the two main causes for the deterioration of PLs in fish muscle during storage. Most content of PL molecular species increased and then decreased gradually. However, some special PE molecular species with former low abundance, such as PE 32:1, PE 34:2, and PE 34:1, emerged during the storage in quantity. It indicated that those PE molecular species may come from the microbe bred in the muscle. This phenomenon was found and discussed for the first time. The possible relevance between the emergence of these special PE molecular species and the freshness of the fish muscle during storage will be investigated in further studies.
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