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Stem cell transplantation, especially treatment with bone marrow mesenchymal stem cells (BMSCs), has been considered a promising therapy for the locomotor and neurological recovery of spinal cord injury (SCI) patients. However, the clinical benefits of BMSCs transplantation remain limited because of the considerably low viability and inhibitory microenvironment. In our research, low‐intensity pulsed ultrasound (LIPUS), which has been widely applied to clinical applications and fundamental research, was employed to improve the properties of BMSCs. The most suitable intensity of LIPUS stimulation was determined. Furthermore, the optimized BMSCs were transplanted into the epicenter of injured spinal cord in rats, which were randomized into four groups: (a) Sham group (n = 10), rats received laminectomy only and the spinal cord remained intact. (b) Injury group (n = 10), rats with contused spinal cord subjected to the microinjection of PBS solution. (c) BMSCs transplantation group (n = 10), rats with contused spinal cord were injected with BMSCs without any priming. (d) LIPUS‐BMSCs transplantation group (n = 10), BMSCs stimulated with LIPUS were injected at the injured epicenter after contusion. Rats were then subjected to behavioral tests, immunohistochemistry, and histological observation. It was found that BMSCs stimulated with LIPUS obtained higher cell viability, migration, and neurotrophic factors expression in vitro. The rate of apoptosis remained constant. After transplantation of BMSCs and LIPUS‐BMSCs postinjury, locomotor function was significantly improved in LIPUS‐BMSCs transplantation group with higher level of brain‐derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in the epicenter, and the expression of neurotrophic receptor was also enhanced. Histological observation demonstrated reduced cavity formation in LIPUS‐BMSCs transplantation group when comparing with other groups. The results suggested LIPUS can improve BMSCs viability and neurotrophic factors expression in vitro, and transplantation of LIPUS‐BMSCs could promote better functional recovery, indicating possible clinical application for the treatment of SCI.

The Qimantagh area of Northwest China lies in the western part of the East Kunlun Orogenic Belt and is characterized by extensive magmatism, particularly in the Triassic. However, recent research has shown that Devonian magmatism was also widespread in this area and has a genetic relationship with mineralization. This article presents a detailed study of three types of Early Devonian intrusions: high-K calc-alkaline granites, A-type granites, and mafic intrusions, all from the Qimantagh region. These rocks were subjected to precise zircon U–Pb dating, major and trace element analyses, and Sr–Nd isotope measurements, focusing on the Lalingzaohuo (eastern Qimantagh) and Yemaquan (central Qimantagh) monzogranites, as well as the coeval Tanbeixuefeng (western Qimantagh) mafic dike swarm. To better understand the Early Devonian igneous activity in the Eastern Kunlun, data for other coeval granitoids were compared with our data. The Yemaquan monzogranite yielded a mean zircon U–Pb age of 400.5 ± 1.4 Ma....

To investigate how a back propagation neural network based on genetic algorithm (GA-BPNN) optimizes the low-intensity pulsed ultrasound (LIPUS) stimulation parameters to improve the bone marrow mesenchymal stem cells (BMSCs) viability further. The LIPUS parameters were set at various frequencies (0.6, 0.8, 1.0, and 1.2 MHz), voltages (5, 6, 7, and 8 V), and stimulation durations (3, 6, and 9 minutes). As only some discrete points can be set up in the experiments, the optimal LIPUS stimulation parameter may not be in the value of these settings. The GA-BPNN algorithm is used to optimize parameters of LIPUS to increase the BMSCs viability further. The BMSCs viability of the LIPUS-treated group was improved up to 19.57% (P<0.01). With the optimization via the GA-BPNN algorithm, the viability of BMSCs was further improved by about 5.36% (P<0.01) under the optimized condition of 6.92 V, 1.02 MHz, and 7.3 min. LIPUS is able to improve the BMSCs viability, which can be improved further by LIPUS with parameter optimization via GA-BPNN algorithm.

There are many various patterns for electricity market. Different countries adopt different patterns according to their own characteristics. However, no matter what pattern they adopt, there must be a certain structure similar to long-term market and real-time market where power sellers usually make electricity transaction. From the view of electricity power sellers, it is the key for hydropower enterprise (Power seller) to find an optimal sale strategy which can maximize the amount of electricity sale while minimizing the probability of risk. In this paper, on the base of analysis on the deterministic gross generation, a mathematic model is established to gain the maximal income of electricity sale in the case of considering risk factors, and to investigate the relationship between risk factors and electricity sale distribution in the two markets, long-term market and real-time market. Then, subsequently, the optimal strategy of electricity sale distribution of gross generation will be obtained in every market in order to maximize the total expected benefit. The feasibility and validness of the Model are verified by its application to a case as well.

Color and physico-mechanical properties change from 10 months of natural outdoor weathering for injection molded bamboo flour (BF)/polypropylene (PP) foamed composites were investigated. The composite surface morphology, before and after exposure, was observed by using environmental scanning electron microscopy (ESEM). Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) were used to characterize the chemical structures. Natural weathering was shown to cause more discoloration and surface deterioration, while the physico-mechanical properties, rheological behavior, and thermal stability were less negatively affected for composites with higher BF amount ranging from 0 to 35 wt%. The rheological behavior results indicated decreases in the storage and loss moduli and the complex viscosity of weathered composites. Crossover frequency was found to increase and the average molecular weight decreased. The initial thermal decomposition temperature declined in foamed PP by 25℃ and in 35% BF/PP foamed composite by 6℃, indicating a slight decline in thermal stability, as shown by thermogravimetric (TG) analysis. Photodegradation, photooxidation, and matrices chain scission in the composites were confirmed by FTIR and XPS analyses.

This work mainly studied the effects of hot extrusion on microstructure, texture and mechanical properties of Mg-5Li-3Al-2Zn alloy. The results show that the microstructures of as-cast and as-extruded alloys both consist of α-Mg matrix and lamellar eutectic structure (α-Mg and AlLi phases). During the hot extrusion, the large eutectic structure of as-cast alloy was crushed into small eutectic structure and the grains were effectively refined. A {0002} basal texture was formed after hot extrusion. The as-extruded alloy exhibits remarkably improved tensile properties, which is mainly attributed to the grain refinement and the formation of texture.

Based on the analysis of water supply and water demand in Tianjin city, the early-warning index system of water resources was determined. Then, applying the relative principle of catastrophe theory, all kinds of the slope change-points of early-warning index curves, including the differences of water supply and water demand, water supply, water demand, increasing curve of population in Tianjin, total industrial output value and increasing curve of GDP are obtained by the rate analysis for slope change-point. So, the slope change-points model is established for early-warning system of water resources security in Tianjin City. After applying the theory of set pair analysis, which set a pair of “water-rich state (flood disaster)” and “water-shortage state (drought disaster)”, early-warning threshold and degree of water resources security are uniformly presented by the index of difference of water supply and demand. In this way, we could illustrate the early-warning degrees. Finally, according to the ...

the layout and the characteristics of the cascade reservoirs and hydropower stations in the upper reaches of the Yellow River, determine that cascade hydropower stations scheduling must be operated based on the joint operation between Longyangxia and Liujiaxia cascade hydropower stations, especially on flood control operation. This paper deeply analyzes design flood storage area of the Liujiaxia composition and Longyangxia-Liujiaxia joint flood regulating principle on the basis of analyzing and calculating each ten-day design flood of the Tangnaihai above main stream and the intervals. Therefore, the reasonable combination of interval flood and the process of Longyangxia reservoir flood discharge is confirmed, and thereby, studying Liujiaxia reservoir inflowing design flood under a controlling operation of flood limited water level for a period of ten-day to ensure the safety of Liujiaxia reservoir flood control.

Because of nonlinear dynamic performances and uncertain working environment, precise motion control of Automatic Underwater Vehicle (AUV) has always been a problem. For the time lag and nonlinearity of AUV, a new method called Predictive S Control (PSC) based on model of Support Vector Machine (SVM) is presented. Firstly, in establishing the model of SVM, the fine property of approaching to the nonlinear model is utilized to solve the predictive problem. Then, the control parameters of S controller are optimized by constructing the error function. At last the motion control of AUV is realized. It has been proved that this method is feasible and effective. Using this method, a good control result is obtained in the simulation.

Based on the historic and current status of the development of tidal power station, the developments of tidal power station is reviewed in this paper, including unit selection, hydropower calculations, station construction and integrated management. Thus, operating Principle, various technical problems and improving technologies of tidal power station management are systematically analyzed. Then, combined with the latest advances of current research of tidal power, the tendency and further research on operation management of tidal power station is presented in the end.

Owing to the complex operating environment of underwater vehicles, many uncertainties of sensors data, big noises of sensors , low precision and high rate of wild points of underwater acoustic sensors, data processing of motion sensors data for underwater vehicle navigation system becomes extremely important. The integrated navigation system of autonomous underwater vehicle based on dead-reckoning is introduced. An modified adaptive Kalman filter is adopted for underwater vehicle sensors information data processing. Experimental results show that the modified self-adaptive Kalman filter(SAKF) is effective, and can meet the underwater robots perform a variety of tasks in the navigation and positioning accuracy..

Successful applications of electrical capacitance tomography (ECT) depend on the speed and precision of the image reconstruction algorithms. In this paper, based on the semiparametric model, a generalized objective functional that considers the outliers in the measured capacitance data and the model error is proposed. A regularized combination minimax estimation is developed. An efficient algorithm, which integrates the advantages of the homotopy method where the homotopy equation is designed by the fixed-point homotopy and solved using the fixed-point iteration algorithm based on the alternate iteration scheme, the quantum particle swarm optimization algorithm that is coupled with the crossover and mutation operators, and the simulated annealing algorithm, is proposed. This algorithm is tested by the noise-free capacitance data and the noise-contaminated capacitance data, and encouraging results are observed. Numerical simulation results reveal the effectiveness and superiority of the proposed algorithm. In the cases of the reconstructed objects considered in this paper, the reconstructed results by the proposed algorithm show great improvement in the spatial resolution and accuracy. The spatial resolution of the reconstructed images is enhanced, and the artifacts in the reconstructed images can be removed effectively. Furthermore, the reconstructed results by the proposed algorithm under the noise-contaminated capacitance data reveal that the proposed algorithm is very competent to deal with the inaccurate nature in the capacitance data. Consequently, a promising algorithm is introduced for ECT image reconstruction.

Electrical capacitance tomography (ECT) is considered as a promising tomography technology, and exactly reconstructing the original objects is highly desirable in real applications. In this paper, a generalized image reconstruction model that simultaneously considers the inaccurate property in the measured capacitance data and the linearization approximation error is presented. A generalized objective function, which has been developed using a combinational M-estimation and an extended stabilizing item, is proposed. The objective function unifies six estimation methods into a concise formula, where different estimation methods can be easily obtained by selecting different parameters. The homotopy method that integrates the beneficial advantages of the alternant iteration scheme is employed to solve the proposed objective function. Numerical simulations are implemented to evaluate the numerical performances and effectiveness of the proposed algorithm, and the numerical results reveal that the proposed algorithm is efficient and overcomes the numerical instability in the process of ECT image reconstruction. For the reconstructed objects in this paper, a dramatic improvement in accuracy and spatial resolution can be achieved, which indicates that the proposed algorithm is a promising candidate for solving ECT inverse problems.

Regional operation of the electricity market has begun in China. With the development of China’s market economy, hydropower will enter the arena of bidding for connection to the grid in light of “fair, impartial and open” principles. For the electricity market, the solution of an inter-plant economical operation of a cascade hydropower system is extremely important. If a hydropower company is incapable of predicting the generation capability and the amount of generation of hydropower stations as well as the risk-rate corresponding to various generation amounts, then there is no information available to the hydropower company to refer to when it makes future agreements in a certain period. This paper develops mathematical models of (1) total minimum stored energy consumption and (2) total minimum water consumption for a cascade hydropower system. The models provide a solution to the problem of rational distribution of next-day’s generating schedule in a cascade hydropower system awarded a contract in the bidding for connection to the grid. A case study is conducted to verify the effectiveness and applicability of the methodology.

Gene mapping of a mouse coat mutation has been investigated. First, 100 10-bp random primers were used to amplify DNA, but the mutation could not be located by this method because there were no correlation between the amplified products and coat phenotypes. Second, by usingIdh1, Car2, Mup1, Pgb1, Hbb, Es10, Es1, Mod1, Gdc1, Ce2, Es3 as genetic markers, linkage test crosses (two-point test) consisting of intercrossing uncovered BALB/c mice (homozygotes) to CBA/N and C57BV6 mice with normal hair and backcrossing the heterozygotes of the F1 to the uncovered BALB/c mice were made. It was soon evident that the mutation was linked toEs3 on chromosome 11. Furthermore, three-point test was made by usingEs3 and D11Mit8 (a microsatellite DNA) as genetic markers. The result showed that the mutation was linked toEs3 with the percentage recombination of (7.89 ± 2.19)%, and linked to Dl1Mit8 with the percentage recombination of (26.30± 3.57)%. The percentage recombination betweenEs3 and D11Mit8 was (32.90±3.81)%. The mutation was named Uncovered, with the symbolUncv. According to the recombinations, the loci order was D11Mit8-26.30±3.57-Uncv- 7.89 -2.19-Es3. From the location on the chromosome, it was concluded that the mutation was a new mutation which affected the skin and hair structure of mouse. TheUncv has entered MGD (Mouse Genome Database).

A pair of mutant mice with a first sparse coat appeared spontaneously in the production stock of BALB/c mice with a normal coat. After being sib-mated, they produced three phenotypes in their progeny: mice with normal hair, mice with a first sparse coat and then a fuzzy coat, and uncovered mice. Genetic studies revealed the mutants had inherited an autosomal monogene that was semi-dominant. By using 11 biochemical loci – Idh, Car2, Mup1, Pgm1, Hbb, Es1, Es10, Gdc, Ce2, Mod1 and Es3 – as genetic markers, two-point linkage tests were made. The results showed the gene was assigned to chromosome 11. The result of a three-point test with Es3 and D11Mit8 (microsatellite DNA) as markers showed that the mutation was linked to Es3 with the recombination fraction 7·89±2·19%, and linked to D11Mit8 with the recombination fraction 26·30±3·57%. The recombination fraction between Es3 and D11Mit8 was 32·90±3·81%. It is suggested that the mutation is a new genetic locus that affected the skin and hair structure of the mouse. The mutation was named uncovered, with the symbol Uncv. Further studies showed the mutation affected not only the histology of skin and hair but also the growth and reproductive performance of the mice. The molecular characterization of the Uncv locus needs to be further studied.

This paper examines long-term optimal operation using dynamic programming for a large hydropower system of 10 reservoirs in Northeast China. Besides considering flow and hydraulic head, the optimization explicitly includes time-varying electricity market prices to maximize benefit. Two techniques are used to reduce the ‘curse of dimensionality’ of dynamic programming with many reservoirs. Discrete differential dynamic programming (DDDP) reduces the search space and computer memory needed. Object-oriented programming (OOP) and the ability to dynamically allocate and release memory with the C++ language greatly reduces the cumulative effect of computer memory for solving multi-dimensional dynamic programming models. The case study shows that the model can reduce the ‘curse of dimensionality’ and achieve satisfactory results.

Economic risk of project is the largest and most important risk. Along with carrying the Middle Route of the South-to-North Water Diversion Project into execution, how much water to transfer is a controversial problem. Synthetically considering the risk characteristic of the hydraulic engineering benefit for flood control, electricity generation, water supply, irrigation efficiency and annual cost, a model of economic risk analysis is established with the Principle Of Maximum Entropy (POME). It presents comprehensively contrastive analysis on the economic risk about 3 schemes (water transfer of 8.2×109 m3, 15×109 m3, 22×109 m3 respectively) for Middle Route of South-North Water Diversion Project, which will provide some references for the ascertaining of water-transfer volume and determining the base for more detailed risk analysis.

Diabetic neuropathic pain is associated with increased glutamatergic input in the spinal dorsal horn. Group I metabotropic glutamate receptors (mGluRs) are involved in the control of neuronal excitability, but their role in the regulation of synaptic transmission in diabetic neuropathy remains poorly understood. Here we studied the role of spinal mGluR5 and mGluR1 in controlling glutamatergic input in a rat model of painful diabetic neuropathy induced by streptozotocin. Whole-cell patch-clamp recordings of lamina II neurons were performed in spinal cord slices. The amplitude of excitatory post-synaptic currents (EPSCs) evoked from the dorsal root and the frequency of spontaneous EPSCs (sEPSCs) were significantly higher in diabetic than in control rats. The mGluR5 antagonist 2-methyl-6-(phenylethynyl)-pyridine (MPEP) inhibited evoked EPSCs and sEPSCs more in diabetic than in control rats. Also, the percentage of neurons in which sEPSCs and evoked EPSCs were affected by MPEP or the group I mGluR agonist was significantly higher in diabetic than in control rats. However, blocking mGluR1 had no significant effect on evoked EPSCs and sEPSCs in either groups. The mGluR5 protein level in the dorsal root ganglion, but not in the dorsal spinal cord, was significantly increased in diabetic rats compared with that in control rats. Furthermore, intrathecal administration of MPEP significantly increased the nociceptive pressure threshold only in diabetic rats. These findings suggest that increased mGluR5 expression on primary afferent neurons contributes to increased glutamatergic input to spinal dorsal horn neurons and nociceptive transmission in diabetic neuropathic pain.

The immune algorithm-based particle swarm optimization (IA-PSO), which is proposed by involving the immune information processing mechanism into the original particle swarm optimal algorithm, improves the ability to find the globally excellent result and the convergence speed with its special concentration selection mechanism and immune vaccination. Based on analyzing the model of load distribution among cascade hydropower stations and the traits of IA-PSO, the corresponding mathematical description and the solution procedure made with IA-PSO are given in detail. The result demonstrates that IA-PSO can achieve both a superior load distribution scheme and a higher convergence precision as compared to PSO, and will hopefully be applied to solving more extensive optimization problems.