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21.
Strategically fabricated theranostic nanocarrier delivery system is an unmet need in personalized medicine. Herein, this study reports a versatile folate receptor (FR) targeted nanoenvelope delivery system (TNEDS) fabricated with gold core silica shell followed by chitosan–folic acid conjugate surface functionalization by for precise loading of doxorubicin (Dox), resembled as Au@SiO2‐Dox‐CS‐FA. TNEDS possesses up to 90% Dox loading efficiency and internalized through endocytosis pathway leading to pH and redox‐sensitive release kinetics. The superior FR‐targeted cytotoxicity is evaluated by the nanocarrier in comparison with US Food and Drug Administration (FDA)‐approved liposomal Dox conjugate, Lipodox. Moreover, TNEDS exhibits theranostic features through caspase‐mediated apoptosis and envisages high surface plasmon resonance enabling the nanoconstruct as a promising surface enhanced Raman scattering (SERS) nanotag. Minuscule changes in the biochemical components inside cells exerted by the TNEDS along with the Dox release are evaluated explicitly in a time‐dependent fashion using bimodal SERS/fluorescence nanoprobe. Finally, TNEDS displays superior antitumor response in FR‐positive ascites as well as solid tumor syngraft mouse models. Therefore, this futuristic TNEDS is expected to be a potential alternative as a clinically relevant theranostic nanomedicine to effectively combat neoplasia.  相似文献   
22.
Items made of glass, ceramic, etc. are normally stored in stacks and get damaged during the storage due to the accumulated stress of heaped stock. These items are known as breakable items. Here a multi-item inventory model of breakable items is developed, where demands of the items are stock dependent, breakability rates increase linearly with stock and nonlinearly with time. Due to non-linearity and complexity of the problem, the model is solved numerically and final decisions are made using Genetic Algorithm (GA). In a particular case, model is solved analytically as well as numerically and results are compared. Models are developed with both crisp and uncertain inventory costs. For uncertain inventory costs both fuzzy and stochastic parameters are considered. A chance constrained approach is followed to deal with simultaneous presence of stochastic and fuzzy parameters. Different numerical examples are used to illustrate the problem for different cases.  相似文献   
23.
The paper deals with an economic manufacturing quantity (EMQ) model for time-dependent (quadratic) demand pattern. Every manufacturing sector wants to produce perfect quality items. But in long run process, there may arise different types of difficulties like labor problem, machinery capabilities problems, etc., due to that the machinery systems shift from in-control state to out-of-control state as a result the manufacturing systems produce imperfect quality items. The imperfect items are reworked at a cost to become the perfect one. The rework cost may be reduced by improvements in product reliability i.e., the production process depend on time and also the reliability parameter. We want to determine the optimal product reliability and production rate that achieves the biggest total integrated profit for an imperfect manufacturing process using Euler–Lagrange theory to build up the necessary and sufficient conditions for optimality of the dynamic variables. Finally, a numerical example is discussed to test the model which is illustrated graphically also.  相似文献   
24.
Recently, in the literature, a measure of tail heaviness has been proposed based on Rényi entropy. This measure is very useful in the sense that it can be used to measure tail heaviness even for the distributions for which the kurtosis measure does not exist. Nadarajah and Zografos [Nadarajah, Zografos, Information Sciences 153 (2003), 119-138] have derived the expression for this measure for different univariate continuous distributions. But, this measure can only be used for the lifetime of a new item. In case of used item, this measure needs some modification. In this paper, we have modified the measure accordingly so that it can be used in the case of used item and also for the new item. We have also derived expressions for this measure for sixteen different univariate distributions and ten other standard distributions derived from the general distributions used in reliability and survival analysis. The most of the results obtained in the literature in this direction can be obtained as particular cases of our general results.  相似文献   
25.
A novel approach has been taken to produce (1) spherical Al2O3 particles by decarbonisation and (2) spherical AlN particles by nitridation and subsequent decarbonisation of C@Al2O3 composite particles. C@Al2O3 composite particles have been prepared by heterogeneous nucleation and crystallisation of Al(NO3)3 on surfactant encapsulated carbon nano particles followed by evaporative decomposition of the nitrate. Overpressure (0.4 MPa) of nitrogen and a temperature range (1723–1873 K) have been used for nitridation. Whiskers as well as spherical particles of AlN have been observed in the final product. The final product has been characterised by X-Ray Diffraction, Scanning Electron Microscope and Carbon–Hydrogen–Nitrogen content analysis by Elemental Analyser and the mechanism of the nitridation reaction has been analysed. The average size of the spherical AlN particles consisting of crystallites in nano-dimensions (30–50 nm) could be varied from 100 nm to 8 μm by changing the composition of the sol.  相似文献   
26.
The experimental results of an air-core pulse transformer are presented, which is very compact (<10 Kg in weight) and is primed by a capacitor bank that is fabricated in such a way that the capacitor bank with its switch takes the shape of single-turn rectangular shaped primary of the transformer. A high voltage capacitor assembly (pulse-forming-line capacitor, PFL) of 5.1 nF is connected with the secondary of transformer. The transformer output voltage is 160 kV in its second peak appearing in less than 2 μS from the beginning of the capacitor discharge. The primary capacitor bank can be charged up to a maximum of 18 kV, with the voltage delivery of 360 kV in similar capacitive loads.  相似文献   
27.
28.
This paper presents the recently introduced modified subgradient method for optimization and its effectiveness in a fuzzy transportation model. Here a multi-item balanced transportation problem (MIBTP) is formulated where unit transportation costs are imprecise. Also available spaces and budgets at destinations are limited but imprecise. The objective is to find a shipment schedule for the items that minimizes the total cost subjected to imprecise warehouse and budget constraints at destinations. The proposed model is reduced to a multi-objective optimization problem using tolerances, then to a crisp single-objective one using fuzzy non-linear programming (FNLP) technique and Zimmermann's method. The above fuzzy MIBTP is also reduced to another form of deterministic one using modified sub-gradient method (MSM). These two crisp optimization problems are solved by Genetic Algorithm (GA). As an extension, fuzzy multi-item balanced solid transportation problems (STPs) with and without restrictions on some routes and items are formulated and reduced to deterministic ones following FNLP and Zimmermann's methods. These models are also solved by GA. Models are illustrated numerically, optimum results of fuzzy MIBTP from two deductions are compared. Results are also presented for different GA parameters.  相似文献   
29.

In welding processes, the selection of optimal process parameter settings is very important to achieve best weld qualities. In this work, neuro-multi-objective evolutionary algorithms (EAs) are proposed to optimize the process parameters in friction stir welding process. Artificial neural network (ANN) models are developed for the simulation of the correlation between process parameters and mechanical properties of the weld using back-propagation algorithm. The weld qualities of the weld joint, such as ultimate tensile strength, yield stress, elongation, bending angle and hardness of the nugget zone, are considered. In order to optimize those quality characteristics, two multi-objective EAs that are non-dominated sorting genetic algorithm II and differential evolution for multi-objective are coupled with the developed ANN models. In the end, multi-criteria decision-making method which is technique for order preference by similarity to the ideal solution is applied on the Pareto front to extract the best solutions. Comparisons are conducted between results obtained from the proposed techniques, and confirmation experiments are performed to verify the simulated results.

  相似文献   
30.
Barium orthovanadate (Ba3V2O8), a derivative of perovskite family has been prepared using a mixed-oxide technique. The room temperature X-ray diffraction analysis has confirmed the formation of a single phase compound in trigonal crystal structure. The study of microstructure by scanning electron microscopy shows that the compound has well defined grains, distributed uniformly throughout the surface. The studies of dielectric parameters (εr and tan δ) of the compound as a function of temperature at three different frequencies (100, 500, 1,000 kHz) exhibit that they are almost temperature independent at low and medium temperature ranges. Detailed studies of impedance and related parameters exhibit that the electrical properties of the material are strongly dependent on temperature, and bear a good correlation with its microstructures. The bulk resistance, evaluated from complex impedance spectra, is found to be decreasing with rise in temperature. It shows that the material has negative temperature co-efficient of resistance similar to that of semiconductors. The same behaviour has also been observed in the study of I–V characteristics of the material. The complex electric modulus analysis indicates the possibility of hopping conduction mechanism in the system with non-exponential type of conductivity relaxation. The nature of variation of dc conductivity with temperature confirms the Arrhenius behavior of the material. The ac conductivity spectra show a typical signature of an ionic conducting system, and are found to obey Jonscher’s universal power law.  相似文献   
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