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21.
This study evaluated the releasing performance of tara tannin, a cocktail of plant polyphenols, incorporated in submicron fiber, produced by the electrospinning process. Polylactic acid was used as a polymer matrix that carried two loading levels of tara tannin, 14.3 and 22.3% dry weight in the final product. The fiber diameter of composite fibers was in the range 500–700 nm. The release of tara tannin was controlled by material attachment as there was no evidence of chemical bonding between materials. This was further confirmed by FTIR and DSC. From the five combinations of acid that were presented in tara tannin, galloylquinic acid, with the smallest molecular weight composition, was released in the largest proportion (%molar) and exhibited antioxidant activity. This was confirmed by 2,2‐diphenyl‐1‐picrylhydrazyl assay and HPLC‐MS analyses. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43646.  相似文献   
22.
The aim of these investigations is to find the numerical performances of the delay differential two-prey and one-predator system. The delay differential models are very significant and always difficult to solve the dynamical kind of ecological nonlinear two-prey and one-predator system. Therefore, a stochastic numerical paradigm based artificial neural network (ANN) along with the Levenberg-Marquardt backpropagation (L-MB) neural networks (NNs), i.e., L-MBNNs is proposed to solve the dynamical two-prey and one-predator model. Three different cases based on the dynamical two-prey and one-predator system have been discussed to check the correctness of the L-MBNNs. The statistic measures of these outcomes of the dynamical two-prey and one-predator model are chosen as 13% for testing, 12% for authorization and 75% for training. The exactness of the proposed results of L-MBNNs approach for solving the dynamical two-prey and one-predator model is observed with the comparison of the Runge-Kutta method with absolute error ranges between 10−05 to 10−07. To check the validation, constancy, validity, exactness, competence of the L-MBNNs, the obtained state transitions (STs), regression actions, correlation presentations, MSE and error histograms (EHs) are also provided.  相似文献   
23.
The purpose of this study was to assess and evaluate new bone formation in rabbit marginal mandibular defects using expanded bone marrow-derived osteoprogenitor cells seeded in three-dimensional scaffolds of polycaprolactone/tricalcium phosphate (PCL/TCP). Bone marrow was harvested from the rabbit ilium and rabbit bone marrow-derived osteoprogenitor cells were isolated and expanded in standard culture medium and osteogenic medium supplement. The cells were then seeded into the PCL/TCP scaffolds and the cell/scaffold constructions were implanted into prepared defects in rabbit mandibles. PCL/TCP scaffold alone and autogenous bone graft from the mandible were also implanted into the other prepared defects. The specimens were evaluated at 4 and 8 weeks after the implantation using clinical, radiographic, and histological techniques. The results of the experimental group demonstrated more newly formed bone on the surface and in the pores of the PCL/TCP scaffolds. In addition, the osteoblasts, osteocytes, and new bone trabeculae were identified throughout the defects that were implanted with the cell/scaffold constructions. The PCL/TCP alone group was filled mostly with fibrous cells particularly in the middle region with less bone formation. These results would suggest that the derived osteotoprogenitor cells have the potential to form bone tissue when seeded onto PCL/TCP scaffolds.  相似文献   
24.
This paper proposes a method for solving mixed-integer nonlinear programming problems to achieve or approach the optimal solution by using modified genetic algorithms. The representation scheme covers both integer and real variables for solving mixed-integer nonlinear programming, nonlinear programming, and nonlinear integer programming. The repairing strategy, a secant method incorporated with a bisection method, plays an important role in converting infeasible chromosomes to feasible chromosomes at the constraint boundary. To prevent premature convergence, the appropriate diversity of the structures in the population must be controlled. A cross-generational probabilistic survival selection method (CPSS) is modified for real number representation corresponding to the representation scheme. The efficiency of the proposed method was validated with several numerical test problems and showed good agreement.  相似文献   
25.
This article focuses on the molecular modeling of the release of doxorubicin from capsules composed of glucosamine(ethylene glycol) oligomers. Doxorubicin forms micelle structures with glucosamine(ethylene glycol), and the drug release mechanism can be studied through the modeling of oligomeric bond breaking under acidic, neutral, or basic conditions. Under these conditions, the activation energies were calculated to be 145.51, 135.78, and 287.60 kcal/mol, respectively, at the B3LYP/6-31G//PM3 level. Based on these values, doxorubicin can be released into acidic and neutral solutions but not into basic solution. Ethylene glycol chain length in glucosamine(ethylene glycol) also effects drug release. As the length of ethylene glycol increases, the amount of drug released increases under acidic conditions, but decreases under neutral and basic conditions. When the drug is released from glucosamine(ethylene glycol) oligomers, the drug molecule and glucosamine(ethylene glycol) molecules form a micelle structure. Studies found that, as the length of the ethylene glycol chains increases, the micelle structure is more easily formed. The ethylene glycol group can deliver doxorubicin to cancer cells in micelle form.  相似文献   
26.
The goal of this research is to introduce the simulation studies of the vector-host disease nonlinear system (VHDNS) along with the numerical treatment of artificial neural networks (ANNs) techniques supported by Levenberg-Marquardt backpropagation (LMQBP), known as ANNs-LMQBP. This mechanism is physically appropriate, where the number of infected people is increasing along with the limited health services. Furthermore, the biological effects have fading memories and exhibit transition behavior. Initially, the model is developed by considering the two and three categories for the humans and the vector species. The VHDNS is constructed with five classes, susceptible humans , infected humans , recovered humans , infected vectors , and susceptible vector based system of the fractional-order nonlinear ordinary differential equations. To solve the number of variations of the VHDNS, the numerical simulations are performed using the stochastic ANNs-LMQBP. The achieved numerical solutions for solving the VHDNS using the stochastic ANNs-LMQBP have been described for training, verifying, and testing data to decrease the mean square error (MSE). An extensive analysis is provided using the correlation studies, MSE, error histograms (EHs), state transitions (STs), and regression to observe the accuracy, efficiency, expertise, and aptitude of the computing ANNs-LMQBP.  相似文献   
27.
The current investigations are presented to solve the fractional order HBV differential infection system (FO-HBV-DIS) with the response of antibody immune using the optimization based stochastic schemes of the Levenberg-Marquardt backpropagation (LMB) neural networks (NNs), i.e., LMBNNs. The FO-HBV-DIS with the response of antibody immune is categorized into five dynamics, healthy hepatocytes (H), capsids (D), infected hepatocytes (I), free virus (V) and antibodies (W). The investigations for three different FO variants have been tested numerically to solve the nonlinear FO-HBV-DIS. The data magnitudes are implemented 75% for training, 10% for certification and 15% for testing to solve the FO-HBV-DIS with the response of antibody immune. The numerical observations are achieved using the stochastic LMBNNs procedures for soling the FO-HBV-DIS with the response of antibody immune and comparison of the results is presented through the database Adams-Bashforth-Moulton approach. To authenticate the validity, competence, consistency, capability and exactness of the LMBNNs, the numerical presentations using the mean square error (MSE), error histograms (EHs), state transitions (STs), correlation and regression are accomplished.  相似文献   
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