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To reduce the loss of the high-frequency drive circuit of silicon carbide metal oxide semiconductor transistor (SiC MOSFET) and to better utilize the performance of the SiC MOSFET, a high-frequency drive circuit based on discrete components (DC-RGD) is proposed in this paper. The inductance is added to provide a low-impedance circuit for the gate charge/discharge circuit of the SiC MOSFET, enhancing the circuit’s immunity to interference. At the same time, an auxiliary switching tube is added to form an active clamping circuit to reduce the impact of parasitic parameters on the drive waveform in high-frequency applications. A negative voltage is generated by adding a series capacitor to the drive circuit, ensuring the auxiliary switch is on during SiC MOSFET turn-off. This switch is not driven by an additional drive circuit, thus simplifying the circuit. The operation and losses of the circuit are analyzed, and the design methodology of the circuit is given. Finally, a Boost converter with an input of 24 V and an output of 48 V/5 A is constructed. The operating waveforms at a frequency of 0.5 MHz are tested, and the loss of the driving circuit is only 0.317 W. The results show that the proposed driving circuit ensures the reliability of the SiC MOSFETs and is able to solve the problem of the driving waveform oscillations efficiently, with a better anti-interference capability and lower loss.

The mechanisms underlying type-2 diabetic neuropathic pain (DNP) are unclear. This study investigates the coupling of postsynaptic density-95 (PSD-95) to N-methyl-D-aspartate receptor subunit 2B (GluN2B), and the subsequent phosphorylation of GluN2B (Tyr1472-GluN2B) in the spinal cord in a rat model of type-2 DNP. Expression levels of PSD-95, Tyr1472-GluN2B, Ca2+/calmodulin-dependent protein kinase II (CaMKII) and its phosphorylated counterpart (Thr286-CaMKII), and α-amino-3-hydroxy-5-methyl-4-soxazole propionic acid receptor subtype 1 (GluR1) and its phosphorylated counterpart (Ser831-GluR1) were significantly increased versus controls in the spinal cord of type-2 DNP rats whereas the expression of total spinal GluN2B did not change. The intrathecal injection of Ro25-6981 (a specific antagonist of GluN2B) or Tat-NR2B9c (a mimetic peptide disrupting the interaction between PSD-95 and GluN2B) induced an antihyperalgesic effect and blocked the increased expression of Tyr1472-GluN2B, CaMKII, GluR1, Thr286-CaMKII, and Ser831-GluR1 in the spinal cords; the increase in spinal cord PSD-95 was not affected. These findings indicate that the PSD-95-GluN2B interaction may increase phosphorylation of GluN2B, and subsequently induce the expression of phosphorylation of CaMKII and GluR1 in the spinal cord of type-2 DNP rats. Targeting the interaction of PSD-95 with GluN2B may provide a new therapeutic strategy for type-2 DNP.

The aim of the present study was to further elucidate the role of JAK2/STAT3-CAV-1-NR2B on painful diabetic neuropathy. In vivo, the mechanical withdrawal threshold and thermal withdrawal latency were measured to evaluate neuropathic pain behaviors (n=8), while western blot (n=5) and an immunofluorescence double staining experiment (n=6) were performed to understand the molecular mechanism. In vitro, the individual culture of BV2 mouse microglia cell lines, the co-culture of BV2 mouse microglia cell lines and PC12 rat neuron cell lines, and western blot analysis were performed to understand the molecular mechanism between microglia and neurons. The expression of p-JAK2, p-STAT3, t-CAV-1, and p-NR2B was upregulated in the dorsal horn of DNP rats throughout the experiment. Through the immunofluorescence double staining experiment, it was found that p-STAT3 was mainly expressed in activated microglia, and this condition can be stably maintained for approximately 2 weeks after the establishment of the DNP model. The intrathecal injection of JAK2 inhibitor AG490 can relieve the abnormal expression of p-JAK2, p-STAT3, t-CAV-1, and p-NR2B, and relieve pain. The remission of AG490 began on the third day, and it could be stably sustained for 14 days. In vitro high-glucose induced the activation of p-STAT3 in microglia, thereby upregulating the expression of p-CAV-1 and p-NR2B in neurons in the co-culture system. JAK2 inhibitor AG490 can alleviate the abnormal expression of these proteins in the JAK2/STAT3-CAV-1-NR2B signaling pathway in vitro. Microglial JAK2/STAT3 signaling probably contributes to neuropathic pain by activating the CAV-1-NR2B pathway.

Interval-valued hesitant fuzzy linguistic set, as an extension of linguistic term set and interval-valued hesitant fuzzy set, can effectively describe uncertainty, hesitancy, and inconsistency inherent in decision-making process. In this paper, a method based on comprehensive cloud aggregation operators is developed for solving multi-attribute group decision-making (MAGDM) problems with interval-valued hesitant fuzzy linguistic numbers (IVHFLNs). First, a comprehensive cloud of an IVHFLN is defined according to the cloud model. Using the comprehensive cloud, a distance measure between two comprehensive clouds is proposed and a distance measure for comprehensive cloud matrices is developed. Then, some generalized geometric aggregation operators of comprehensive clouds for IVHFLNs are introduced, including a comprehensive cloud generalized weighted geometric operator, a comprehensive cloud generalized ordered weighted geometric operator, and a comprehensive cloud generalized hybrid geometric operator. Subsequently, two approaches are presented to compute the deviations among attributes. Then, a programming model of maximizing deviation is established to derive the attribute weights objectively. To determine DMs’ weights, a technique for order preference by similarity to ideal solution-based approach is put forward in interval-valued hesitant fuzzy linguistic environment. The individual order of alternatives for each decision maker is obtained by the comprehensive cloud aggregation operator. To generate the collective order of alternatives, a multi-objective assignment model is constructed and transformed into a single-objective program to resolve. Thus, a method based on comprehensive cloud aggregation operators is proposed for MAGDM with IVHFLNs. Finally, two examples of application are given to demonstrate the applicability and effectiveness of the proposed method.

In supply chain management, supplier selection can be treated as a type of hierarchical multi-criteria decision-making (MCDM) problems since it involves various criteria and hierarchical structure among criteria often exists. This paper investigates a kind of MCDM problems with two-level criteria and develops a novel hybrid method integrating TL-ANP (2-tuple linguistic analytic network process) and IT-ELECTRE II (interval 2-tuple Elimination and Choice Translating Reality II). Considering interactions among criteria, a TL-ANP approach, in which comparison matrices are consistent 2-tuple linguistic preference relations, is put forward to determine weights of criteria and sub-criteria. To deal with the case of criteria being not compensated, an IT-ELECTRE II approach is proposed. In this approach, ratings of alternatives on sub-criteria are represented as interval 2-tuple linguistic variables. A possible degree and a likelihood-based preference degree are respectively defined, followed by concordance, discordance and indifferent sets. Afterwards, concordance and discordance indices are identified and applied to establish net concordance and net discordance indices. Further, comprehensive dominant values of alternatives are obtained to rank alternatives. Thereby, a novel hybrid method is presented for MCDM with two-level criteria under interval 2-tuple linguistic environment. At length, a real case of supplier selection is examined and comparison analyses are conducted to illustrate the application and superiority of the proposed method. [ABSTRACT FROM AUTHOR]

This paper investigates the group decision making (GDM) problems with interval-valued Atanassov intuitionistic fuzzy preference relations (IV-AIFPRs) and develops a novel method for solving such problems. A new consistency index of an Atanassov intuitionistic fuzzy preference relation (AIFPR) is introduced to judge the consistency of an AIFPR and then a convergent iterative Algorithm I is designed to repair the consistency of an AIFPR with unacceptable consistency. Subsequently, the consistency and acceptable consistency of an IV-AIFPR are defined through separating an IV-AIFPR into two AIFPRs. Based on Algorithm I, a new iterative Algorithm II is devised to repair the consistency of an IV-AIFPR with unacceptable consistency. Afterwards, to determine decision makers’ (DMs’) weights objectively, an optimization model is established by minimizing the deviations between each individual IV-AIFPR and the collective one. This model is skillfully transformed into a linear goal program to resolve sufficiently considering different principles of decision making. A linear program is built to derive interval-valued Atanassov intuitionistic fuzzy (IVAIF) priority weights of alternatives. Then, a TOPSIS (technique for order performance by similarity to an ideal solution) based approach is proposed to rank such IVAIF priority weights. Thereby, a method for GDM with IV-AIFPRs is put forward. At length, a practical example of a virtual enterprise partner selection is provided to illustrate the feasibility and validity of the proposed method. [ABSTRACT FROM AUTHOR]

This paper develops a new method for solving multiple attribute group decision-making (MAGDM) problems with Atanassov’s interval-valued intuitionistic fuzzy values (AIVIFVs) and incomplete attribute weight information. Firstly, we investigate the asymptotic property of the Atanassov’s interval-valued intuitionistic fuzzy (AIVIF) matrix. It is demonstrated that after applying weights an infinite number of times, all elements in an AIVIF matrix will approach the same AIVIFV without regard to the initial values of elements. Then, the weight of each decision maker (DM) with respect to every attribute is determined by considering the similarity degree and proximity degree simultaneously. To avoid weighting an AIVIF matrix too many times, the collective decision matrix is transformed into an interval matrix using the risk coefficient of DMs. Subsequently, to derive the attribute weights objectively, we construct a multi-objective interval-programming model that is solved by transforming it into a linear program. The ranking order of alternatives is generated by the comprehensive interval values of alternatives. Finally, an example of a research and development (R&D) project selection problem is provided to illustrate the implementation process and applicability of the method developed in this paper. [ABSTRACT FROM AUTHOR]

Primary osteoporosis is an age-related disease, and the main cause of this disease is the failure of bone homeostasis. Previous studies have shown that primary osteoporosis is associated with gene mutations. To explore the functional modules of the PPI (protein-protein interaction) network of differentially expressed genes (DEGs), and the related pathways participating in primary osteoporosis. The gene expression profile of primary osteoporosis GSE35956 was downloaded from the GEO (Gene Expression Omnibus) database and included five MSC (mesenchymal stem cell) specimens of normal osseous tissue and five MSC specimens of osteoporosis. The DEGs between the two types of MSC specimens were identified by the samr package in R language. In addition, the functions and pathways of DEGs were enriched. Then the DEGs were mapped to String to acquire PPI pairs and the PPI network was constructed with by these PPI pairs. Topological properties of the network were calculated by Network Analyzer, and modules in the network were screened by Cluster ONE software. Subsequently, the fronting five modules whose P-value was less than 1.0e-05 were identified and function analysis was conducted. A total of 797 genes were filtered as DEGs from these ten specimens of GSE35956 with 660 up-regulated genes and 137 down-regulated genes. Meanwhile, up-regulated DEGs were mainly enriched in functions and pathways related to cell cycle and DNA replication. Furthermore, there were 4,135 PPI pairs and 377 nodes in the PPI network. Four modules were enriched in different pathways, including cell cycle and DNA replication pathway in module 2. In this paper, we explored the genes and pathways involved in primary osteoporosis based on gene expression profiles, and the present findings have the potential to be used clinically for the future treatment of primary osteoporosis.

A numerical simulation method using the model of the gas-cotton two-phase is used to analyze the distribution of the cotton in the rectangular pipeline for a horizontal foreign fiber removed device. According to the motion characteristics of the cotton, the optimum length of the rectangular pipeline is found and the distribution of the cotton in the pipeline is obtained. The simulation results show that the optimum length is for the cross-section pipeline. At the same time, in the range of the cotton mainly flows in the middle of the pipeline bottom and the maximum volume fraction of the cotton is 4.5%, at the both sides of the pipeline bottom the cotton is less and the average volume fraction of the cotton is 1%, and there is no the cotton in the middle and upper part of the pipeline; in the range of , the cotton increases rapidly in the middle and upper part of the pipeline and the volume fraction is about 2.7% at ; in the range of , the cotton flows steadily and the volume fractions of the cotton are the same in the middle and upper part of the pipeline, about 2.7% but 1.5% in the lower part of the one. In addition, for the level centers of the cross-sections perpendicular to the cotton flow direction, in the unsteady zone the volume fraction curves of the cotton are symmetrical like a saddle, and in the steady zone the cotton is evenly distributed and its volume fraction curves are horizontal lines.

This paper analysis the basic principles of the genetic algorithm (GA) and simulated annealing algorithm (SA) thoroughly. According to the characteristics of mutil-objective location routing problem, the paper designs the hybrid genetic algorithm in various components, and simulate achieved the GSAA (Genetic Simulated Annealing Algorithm).Which architecture makes it possible to search the solution space easily and effectively without overpass computation. It avoids effectively the defects of premature convergence in traditional genetic algorithm, and enhances the algorithms global convergence. Also it improves the algorithms convergence rate to some extent by using the accelerating fitness function. Still, after comparing with GA and SA, the results show that the proposed Genetic Simulated Annealing Algorithm has better search ability. And the emulation experiments show that this method is valid and practicable.

Based on the non-linearization of hydraulic cylinder controlled by servo valve system, the system mathematics model was difficult to be deduced. In the paper, by combining the rich model base of AMESim with Powerful function of numerical calculation of Matlab software, combined simulation for two softwares was presented. The simulation results were virtually the actual work conditions; also it provided better reference value for the next experiment research.

Amino group-functionalized magnetic particles have wide applications in enzyme immobilization, DNA extraction, drug delivery, water purification, catalysis, and sensor. In this paper, Fe3O4/PPy microspheres with a well-defined coreshell structure have been prepared through an interfacial polymerization approach without surfactant. The magnetic composite spheres were characterized with XRD, FTIR, SEM, TEM, and magnetometry techniques, and further tested as the adsorbent to isolate plasmid DNA from Escherichia coli (E. coli) DH5α cells. The magnetic separation yields high-quality plasmid DNA in satisfying productivity as compared to the conventional phenolchloroform extraction.

Cotton processing technology in an automatic production line was presented. A pipeline used to set an apparatus for removing the foreign fiber was chosen in the cotton processing technology. The distribution and velocity of the cotton in five positions of the central plane of the pipeline were simulated by the Fluent software. The simulated curves of the cotton distribution and velocity were obtained. According to the curves, there is the optimal length of the cotton conveyed pipeline with a certain cross-section area to set the apparatus for removing the foreign fiber. There is no the steady zone if the pipeline length is shorter than the optimal value, and if longer than it, the pipeline will waste the material and space. The steady zone is determined by the forces. In the certain position of the straight pipeline away from the curved pipeline, the various forces, which act on the cotton or foreign fiber, are in the dynamic equilibrium, and the distribution and velocity of the cotton are steady. For the rectangular pipeline with the cross-section area 2960×120mm , its total length should be 7000mm, the steady zone length of the cotton distribution is about 2500mm, and the steady zone of its velocity is 1000mm. In the common part of their steady zones the apparatus for removing the foreign fiber may be setting rationally.

The reaction of Et3GeCH=CH2 + Et3SiOH → Et3SiO–Ge–Et3 + CH2=CH2 has been studied using quantum chemistry methods. Geometries of reactants, transition states, and products have been optimized respectively at the b3lyp/6-311+g(2d,2p) level. The rate constants were evaluated using canonical variational transition state theory (CVT) and canonical variational transition state theory with small-curvaturetunneling contributions (CVT/SCT) over the temperature range of 200-3500K. The CVT/SCT rate constants exhibit typical non-Arrhenius behavior, and a three-parameter rate-temperature formula has been fitted as follows: k(T)=1.43×10-38T 5.41exp(-13200/T) (in units of cm3 molecule-1s-1).

NC machine plays an irreplaceable role in the modern manufacturing because of its high machining processing accuracy, quality stable, flexibility. Through using the Renishaw ML10 laser interferometer detect the positioning accuracy and repositioning accuracy of X axis and Z axis of the HTC20 series of NC machine tools. According to the detection result compensate NC system to meet the machining accuracy requirement. The result shows that the error compensation of NC system is a effective method to improve the position accuracy of NC machine.

In order to learn the mechanical properties of deep-sea mooring lines, experimental studies involved in strength properties have been carried out in this thesis. In the fiber strength performance test, the small force-large deformation experimental device has been designed and optimized. As the fiber diameter is very small (about 40µm), microscope is chosen to measure the diameter. The intensity curve of fiber is divided into three typical phases. The yield strength, breaking strength and elastic modulus in initial stage can be calculated and the elastic modulus is basically a constant. With the increasing of loading rate, the breaking force reduces and gradually tends to stabilize. It has got the formula, breaking strength ?.

With the continuous development of aviation technology, reliability requirements for air power is growing. As an important component, air static inverter air power has been studied extensively. In this paper, we study the following about the design of the front push-pull forward converter of Aeronautical Static Inverter: First, we design the Push-Pull Forward DC/DC converter control system on the basis of small-signal modeling; Secondly set control system parameters ; Finally, Through the simulation in MATLAB Simulink, we verify the design of the converter control parameter is reasonable, and then verify that Double-loop push-pull Forward DC/DC converter control system in the aviation static inverter is effectiveness.

This paper deals with an isolation design methods of buried segment pipeline for large ground displacement in earthquake. The buried pipeline is always damaged due to the strong shaking and earthquake-induced large or permant ground displacement and deformation (PGD), including liquefaction, rock and soil slope failure, fault and fissure. Based on the seismic response analysis for buried segment pipeline, the isolation mechanism and an equipment for resisting ground displacement trigged by liquefaction and fault is presented in this paper. Some related parameters to isolation system like stiffness and damp of isolator, soil types and its displacement, depth of pipeline, are discussed for developing a reliable isolation system fitting the buried segment pipeline.

Safety is the most important thing in coal mine production. There are many kinds of hidden dangers. In order to discover and eliminate the hidden dangers, the safety supervision becomes one of the most popular methods in current coal mine safety management, but there is not an unitive and normalized flow of collection, transmission, and processing and so on links of safety supervision information. Through applying the thought of business optimization, this paper formed a set of safety supervision information flow, supplied method and technical support for the coal mine management.

The carotid body (CB) senses changes in arterial blood PO2and modulates respiratory movement. It is generally accepted that the dopaminergic type I cells in the CB are chemoreceptors. However, it has not been clarified whether the carotid body has the ability to perceive the stimulation of proinflammatory cytokines. Interleukin 6 (IL-6) as a multifunctional cytokine plays a pivotal role in host defense mechanism. In the present study, we observed the expression of IL-6Ra mRNA and protein in the carotid body using immunohistochemistry, Western blots, and in situ hybridization. The results confirmed the presence of IL-6Ra proteins and mRNAs in the glomus cells of rat carotid body. These results suggest that the function of the carotid body may be influenced by the proinflammatrory cytokines through their receptors. © 2006 Wiley-Liss, Inc.

One hundred and twenty-eight cases of lumbar intervertebral disc protrusion were randomly divided into treatment group, in which 70 cases were treated with electroacupuncture, TDP plus Tuina, and control group, in which 58 cases were treated with electroacupuncture plus TDP. The curative rate in the treatment group was higher than that in the control group (64.3% vs 31.0%,P<0.01). The total effective rate was 100% in the treatment group, 91.3% in the control group; the effect of the former was better than that of the latter (P<0.05).

A series of non‐coplanar and flexible xanthone derivatives (III), (IV) and (VI) is synthesized as potential α‐glucosidase inhibitors.