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101.
In this paper, a sliding-mode approach is proposed for exponential H synchronization problem of a class of master–slave time-delay systems with both discrete and distributed time-delays, norm-bounded nonlinear uncertainties and Markovian switching parameters. Using an appropriate Lyapunov–Krasovskii functional, some delay-dependent sufficient conditions and a synchronization law, which include the master–slave parameters are established for designing a delay-dependent mode-dependent sliding mode exponential H synchronization control law in terms of linear matrix inequalities. The controller guarantees the H synchronization of the two coupled master and slave systems regardless of their initial states. Two numerical examples are given to show the effectiveness of the method.  相似文献   
102.
Determination of amyloid β (Aβ) isoforms and in particular the proportion of the Aβ 1-42 isoform in cerebrospinal fluid (CSF) of patients suspected of Alzheimer’s disease might help in early diagnosis and treatment of that illness. Due to the low concentration of Aβ peptides in biological fluids, a preconcentration step prior to the detection step is often necessary. This study utilized on-chip immunoprecipitation, known as micro-immunoprecipitation (μIP). The technique uses an immunosorbent (IS) consisting of magnetic beads coated with specific anti-Aβ antibodies organized into an affinity microcolumn by a magnetic field. Our goal was to thoroughly describe the critical steps in developing the IS, such as selecting the proper beads and anti-Aβ antibodies, as well as optimizing the immobilization technique and μIP protocol. The latter includes selecting optimal elution conditions. Furthermore, we demonstrate the efficiency of anti-Aβ IS for μIP and specific capture of 5 Aβ peptides under optimized conditions using various subsequent analytical methods, including matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), capillary electrophoresis, microchip electrophoresis, and immunoblotting. Synthetic Aβ peptides samples prepared in buffer and spiked in human CSF were analyzed. Finally, on-chip immunoprecipitation of Aβ peptides in human CSF sample was performed.  相似文献   
103.
The present study was to examine the effects of personal and university bounded factors in students mental health in north of Fars province, Iran. The effects of these factors on university students' psychopathology within a survey design were investigated among 300 participants--94 males and 206 females, who were selected through random sampling method and the degrees of their mental health, were measured by SCL-90-R checklist. Overall findings supported that gender, marital status, socioeconomic status as personal factors, and type of university as within university factor would influence students' mental health. So males, married, and students with moderate and high socioeconomic status had more significant better mental health situation than females, singles and those with low socioeconomic status. Finally, ethnicity, dormitory and non-dormitory residence, native or non-native being, discipline, school and faculty, and academic performance variables were not effective on students' mental health significantly. Here, it was suggested an explanatory triangle model for university students' mental health explanation with respect to gendered and socio-cultural contexts and their implications in clinical and educational settings.  相似文献   
104.
105.
In this paper, we study characteristics of polymers (methylcellulose, hypromellose ((hydroxypropyl)methyl cellulose), poly(vinylpyrrolidone), and poly(vinyl alcohol)) with different chemical structures for microchip electrophoresis of non-denatured protein samples in a plastic microchip made of poly(methyl methacrylate) (PMMA). Coating efficiency of these polymers for controlling protein adsorption onto the channel surface of the plastic microchip, wettability of the PMMA surface, and electroosmotic flow in the PMMA microchannels in the presence of these polymers were compared. Also relative electrophoretic mobility of protein samples in solutions of these polymers was studied. We showed that when using low polymer concentrations (lower than the polymer entanglement point) where the sieving effect is substantially negligible, the interaction of the samples with the polymer affected the electrophoretic mobility of the samples. This effect can be used for achieving better resolution in microchip electrophoresis of protein samples.  相似文献   
106.
The problem of positioning of actuators and sensors on smart materials has been a point of interest in recent years. This is due to the fact that in many practical applications there are limitations in space, weight, etc. of the smart structures, which make the problem of positioning more complex. In addition, it is required that the actuators/sensors have the best possible performance. The development of smart structures technology in recent years has provided numerous opportunities for vibration control applications. The use of piezoelectric ceramics or polymers has shown great promise in the development of this technology. The employment of piezoelectric material as actuators in vibration control is beneficial because these actuators only excite the elastic modes of the structures without exciting the rigid-body modes. This is important since very often only elastic motions of the structures are needed to be controlled. The purpose of this paper is to introduce a novel approach developed for optimizing the location of piezoelectric actuators for vibration suppression of flexible structures. A flexible fin with bonded piezoelectric actuators is considered in this study. The frequency response function (FRF) of the system is then recorded and maximization of the FRF peaks is considered as the objective function of the optimization algorithm to find the optimal placement of the piezoelectric actuators on the smart fin. Three multi-layer perceptron neural networks are employed to perform surface fitting to the discrete data generated by the finite element method (FEM). Invasive weed optimization (IWO), a novel numerical stochastic optimization algorithm, is then employed to maximize the weighted summation of FRF peaks. Results indicate an accurate surface fitting for the FRF peak data and an optimal placement of the piezoelectric actuators for vibration suppression is achieved.  相似文献   
107.
The attempt is made to produce recombinant factor VIII but the first step in producing such product is production and purification of rabbit’s polyclonal antibody against factor VIII. The second and third steps involve monoclonal antibody and recombinant factor VIII production. Factor VIII is one of the most important coagulating factor where its deficiency leads to diseases like hemophilia type A or classic. It is an inherited disease. Previously, it was obtained through fractionation of blood plasma of blood donors. After processing, factor VIII could be used to manage such patients. Due to transfer of viral disease like hepatitis and HIV through factor VIII obtained by fractionation, high cost of production, insufficiency of the donors and the process of virus removal, thus production of factor VIII through recombinant technology can be useful and helpful. The reaction between antibody and antigen is one the most specific reaction; therefore, such reaction can be employed to identify factor VIII. Thereby, rabbits were injected several times with adjuvant-linked antigen to produce antibody. The antibody was separated from the blood sample, purified and used to identify factor VIII in the research.  相似文献   
108.
109.
In this article a methodology is presented to extract indicators that appropriately measure the information society and the digital divide between countries and the relevant statistics that the majority of countries can collect. With the help of content analysis, the entropy method, and consideration of the diffusion aspects of digitalization, 37 reputable information society and digital divide models are analyzed to indentify “core information and communication technology (ICT) indicators.” To overcome the limitation of the nonexistence of data, the information and the knowledge embedded in information society and digital divide models are employed as proxies for experts' opinions for extracting the core ICT indicators. Comparison of the prior indicators and the proposed ones reveals that the former ignore three important dimensions: e-learning, e-government, and networked world enablers.  相似文献   
110.
The paper relates the power engineering problem of the extremal values of effective energy flow to a well established branch of mathematics; namely, the spectral analysis of linear operators. Variation of the effective energy flow in a linear time-invariant power distribution system is studied in the light of numerical range of the operator representing the system [Eqs. (18, 19)]. A knowledge of this range and its extremal values depends on the evaluation of eigenvalues and eigenvectors of a complex network function. In most cases an exact evaluation is practically unattainable (Section V). Simple and practical estimations of the energy dissipation range are presented. The novel spectral approach to energy problems may hopefully find useful applications in power transmission and distribution.  相似文献   
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