DSpace Collection:
http://scholars.ntou.edu.tw/handle/123456789/11111
Wed, 29 Nov 2023 06:14:39 GMT2023-11-29T06:14:39ZIn situ derived sulfated/sulfonated carbon nanogels with multi-protective effects against influenza a virus
http://scholars.ntou.edu.tw/handle/123456789/23740
Title: In situ derived sulfated/sulfonated carbon nanogels with multi-protective effects against influenza a virus
Authors: Lin, Hung-Yun; Luo, Ka-Long; Mao, Ju-Yi; Lin, Chin-Jung; Wang, Chen-Yow; Panny, Lauren; Chen, Shiow-Yi; Lin, Shih-Chao; Huang, Chih-Ching; Harroun, Scott G.; Wang, Robert Y. L.; Wu, Chang-Jer
Abstract: Pandemic of H1N1 infections are frequently reported around the world. Despite the availability of influenza remedies, the high tendency for influenza virus to mutate can lead to the emergence of drug-resistant strains. Additionally, the adverse effects of current anti-flu drugs have led some countries to implement restrictions on to use. In response to the urgent demand to explore and design novel antivirals, we have developed a potent alginate (Alg)-derived anti-flu material, from seaweeds. The preparation involves a one-step pyrolytic reaction of a mixture of sodium alginate and ammonium sulfite (AS), which forms carbonized nanogels (CNGs). We have characterized the chemical and physical properties of these Alg@AS CNGs, validated the anti-flu activity in vitro and in vivo, and explored the underlying mechanism. Our results indicate that the Alg@AS CNGs possess abundant sulfite/sulfate surface moieties, exhibit high biocompatibility and remarkable viral suppression properties against H1N1. The viral suppression of Alg@AS CNGs was found to be superior to other sulfated polysaccharides, such as fucoidan, carrageenan, and chondroitin sulfate. The administration of Alg@AS CNGs to H1N1-infected cells and mice resulted in higher cellular viabilities and mouse survival rates, respectively. Improved pathological indices were observed in lung sections, which showed substantially reduced gene expression of inflammatory mediators in tissues upon Alg@AS CNG treatment. We further showed that the Alg@AS CNGs could inhibit H1N1 infection by binding to viral particles and lowering the oxidative stress in cells. In summary, Alg@AS CNGs that were developed in this study were shown to exhibit potential anti-flu activity that protected animals from this lethal health challenge. These findings show that Alg@AS CNGs could be a potential candidate for future pharmaceutical development as an influenza remedy.Tue, 17 Jan 2023 00:00:00 GMThttp://scholars.ntou.edu.tw/handle/123456789/237402023-01-17T00:00:00ZSolving Nonlinear Boundary Value Problems with Nonlinear Integral Boundary Conditions by Local and Nonlocal Boundary Shape Functions Methods
http://scholars.ntou.edu.tw/handle/123456789/23717
Title: Solving Nonlinear Boundary Value Problems with Nonlinear Integral Boundary Conditions by Local and Nonlocal Boundary Shape Functions Methods
Authors: Liu, Chein-Shan; Chen, Yung-Wei; Shen, Jian-Hung
Abstract: The paper considers the second-order nonlinear boundary value problem (NBVP), which is equipped with nonlinear integral boundary conditions (BCs). Two novel iterative algorithms are developed to overcome the difficulty of NBVP with double nonlinearities involved. In the first iterative algorithm, two nonlocal shape functions incorporating the linear integral terms are derived, and a nonlocal boundary shape function (NBSF) is formulated to assist the solution. Let the solution be the NBSF so that the NBVP can be exactly transformed into an initial value problem. The new variable is a free function in the NBSF, and its initial values are given. For the NBVP with linear integral BCs, three unknown constants are to be determined, while for the nonlinear integral BCs, five unknown constants are to be determined. Twopoint local shape functions and local boundary shape functions are derived for the second iterative algorithm, wherein the integral terms in the boundary conditions are viewed as unknown constants. By a few iterations, four unknown constants can be determined quickly. Through numerical experiments, these two iterative algorithms are found to be powerful for seeking quite accurate solutions. The second algorithm is slightly better than the first, with fewer iterations and a more accurate solution.Sat, 01 Jan 2022 00:00:00 GMThttp://scholars.ntou.edu.tw/handle/123456789/237172022-01-01T00:00:00ZNumerical and Approximate Analytic Solutions of Second-order Nonlinear Boundary Value Problems
http://scholars.ntou.edu.tw/handle/123456789/23716
Title: Numerical and Approximate Analytic Solutions of Second-order Nonlinear Boundary Value Problems
Authors: Liu, Chein-Shan; Shen, Jian-Hung; Chen, Yung-Wei
Abstract: The shooting method consists of guessing unknown initial values, transforming a second-order nonlinear boundary value problem (BVP) to an initial value problem and integrating it to obtain the values at the right end to match the specified boundary condition, which acts as a target equation. In the shooting method, the key issue is accurately solving the target equation to obtain highly precise initial values. Due to the implicit and nonlinear property, we develop a generalized derivative-free Newton method (GDFNM) to solve the target equation, which offers very accurate initial values. Numerical examples are examined to show that the shooting method together with the GDFNM can generate a very accurate solution. Additionally, the GDFNM can successfully solve the three-point nonlinear BVPs with high accuracy. A new splitting-linearizing method is developed to express the approximate analytic solutions of nonlinear BVPs in terms of elementary functions, which adopts the Lyapunov technique by inserting a dummy parameter into the governing equation and the power series solution. Then, linearized differential equations are sequentially solved to derive the analytic solution.Sat, 01 Jan 2022 00:00:00 GMThttp://scholars.ntou.edu.tw/handle/123456789/237162022-01-01T00:00:00ZPeriodic solutions of nonlinear ordinary differential equations computed by a boundary shape function method and a generalized derivative-free Newton method
http://scholars.ntou.edu.tw/handle/123456789/23704
Title: Periodic solutions of nonlinear ordinary differential equations computed by a boundary shape function method and a generalized derivative-free Newton method
Authors: Liu, Chein-Shan; Chang, Chih-Wen
Abstract: In the paper, the period of an n-dimensional nonlinear dynamical system is computed by a formula derived in an (n + 1)-dimensional augmented state space. The periodic conditions and nonlinear first-order ordinary differential equations constitute a specific periodic boundary value problem within a time interval, whose length is an unknown finite constant. Two periodic problems are considered: (I) boundary values are given and (II) boundary values are unknown. A boundary shape function method (BSFM), using the derived shape functions, is devised to an initial value problem with the initial values of new variables given, whereas the terminal values and period are determined by iterative algorithms. The periodic solutions obtained by the BSFM satisfy the periodic conditions automatically. For the sake of comparison, the iterative algorithms based on the shooting method are developed, directly implementing the Poincare map with the fictitious time integration method to determine the periodic solutions, where the periodic conditions are transformed to a mathematically equivalent scalar equation. Owing to the implicit, non-differentiable and nonlinear property of the scalar equation, we develop a generalized derivative-free Newton method (GDFNM) to solve the periodic problem of case (I), which can pick up very accurate period through a few iterations. In numerical examples the computed order of convergence displays the merit of the proposed iterative algorithms. The BSFM and GDFNM are better than the shooting method from the aspects of convergence speed, accuracy and stability. A conventional Poincare mapping method is introduced to solve the periodic problems with the same parameters. The BSFM converges faster and more accurate than the Poincare mapping method and is less sensitive to the initial guesses of initial values and period.Wed, 01 Feb 2023 00:00:00 GMThttp://scholars.ntou.edu.tw/handle/123456789/237042023-02-01T00:00:00Z