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Extended finite element frame based on Abaqus is applied to research the crack propagation problem of two-dimensional long rectangular thin plate. Presuppose type I crack with different horizontal locations and longitudinal dimensions, the propagation characteristics of the edge crack is discussed with the objects of structural flexibility of the thin plate, crack propagation length and plastic zone of crack tip etc. The results indicate that the horizontal location of the initial crack has a small influence on the crack propagation characteristics, and it only affects the local flexibility of the thin plate as well as the dimension and shape of plastic zone of crack tip. The longitudinal dimension of the initial crack obviously nonlinear influence on various parameters of the crack propagation characteristics. In view of the disastrous consequence of crack propagation, the vibration characteristics of the thin plate with different crack dimensions and crack locations are discussed based on the experiment and simulation modal analysis on the thin plate, thus providing basis for prior estimation and control for crack generation and propagation. [ABSTRACT FROM AUTHOR]

Kalman filtering requires the calculation of Jacobian matrix in integrated navigation, when the model is too complex or Jacobian matrix cannot be obtained it is difficult to deal with the issue, the UKF sequential filtering method was proposed. To solve these problems, the method used the UKF filter, the GPS information and navigation information, successively using new information to make correction estimates. The method was used in ship navigation, and the simulation results proved the effectiveness of the algorithm. [ABSTRACT FROM AUTHOR]

The Braitenberg vehicle as a simple conceptual model to characterize the response behaviors of animals or insects under a stimulus is widely used to develop autonomous vehicles able to adapt to the varying environments. Considerable effort has been devoted to building neuromorphic processors with the software in the vehicles; however, there has been no demonstration of Braitenberg vehicle with neuromorphic hardware so far. Herein, a Braitenberg vehicle with simple memristive neuromorphic circuits is built for the first time. This vehicle exhibits adaptive behaviors in the supervised learning process and is eventually trained to conduct the task of tracking path. Moreover, the memristive circuit in the vehicle demonstrates a very short response latency (≈56 ns) to input sensory information. Herein, an alternative promising solution to build self‐adaptive robots and pave the way for the realization of autonomous robots based on memristive neuromorphic circuits is offered.

The article presents information on a study related to the expression of regulator gene proto-oncogene c-myc in the Tarim deer antler in different growth stages. The method includes examination of gene expression location by immunohitochemistry and quantitative analysis of c-myc expression by fluorescent quantitative polymerase chain reaction. The results show positive expression of c-myc in inner root sheath of hair follicle and hair matrix of dermal layer.

Background: The very low density lipoprotein receptor gene (VLDLR), a member of the low density lipoprotein receptor (LDLR) gene family, plays a crucial role in the synthesis of yolk protein precursors in oviparous species. Differential splicing of this gene has been reported in human, rabbit and rat. In chicken, studies showed that the VLDLR protein on the oocyte surface mediates the uptake of yolk protein precursors into growing oocytes. However, information on the VLDLR gene in duck is still scarce. Methods: Full-length duck VLDLR cDNA was obtained by comparative cloning and rapid amplification of cDNA ends (RACE). Tissue expression patterns were analysed by semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR). Association between the different genotypes and egg performance traits was investigated with the general linear model (GLM) procedure of the SAS® software package. Results: In duck, two VLDLR transcripts were identified, one transcript (variant-a) containing an O-linked sugar domain and the other (variant-b) not containing this sugar domain. These transcripts share ∼70 to 90% identity with their counterparts in other species. A phylogenetic tree based on amino acid sequences showed that duck VLDLR proteins were closely related with those of chicken and zebra finch. The two duck VLDLR transcripts are differentially expressed i.e. VLDLR-a is mainly expressed in muscle tissue and VLDLR-b in reproductive organs. We have localized the duck VLDLR gene on chromosome Z. An association analysis using two completely linked SNP sites (T/C at position 2025 bp of the ORF and G/A in intron 13) and records from two generations demonstrated that the duck VLDLR gene was significantly associated with egg production (P < 0.01), age of first egg (P < 0.01) and body weight of first egg (P < 0.05). Conclusions: Duck and chicken VLDLR genes probably perform similar function in the development of growing oocytes and deposition of yolk lipoprotein. Therefore, VLDLR could be a candidate gene for duck egg performance and be used as a genetic marker to improve egg performance in ducks. [ABSTRACT FROM AUTHOR]

To determine whether Ca2+/calcineurin mediated the inhibitory effects of nitric oxide/cGMP-dependent protein kinase (NO/PKG) on the proliferation of vascular smooth muscle cells (VSMC).Proliferation and viability of primary VSMC from rat aorta were measured using [3-(4,5-dimethyl thiazol-2-yl)-2, 5-diphenyl tetrazolium bromide] (MTT) assay and acridine orange and ethidium bromide staining, respectively. Cytosolic Ca2+ was determined by Fluo-3/AM. Calcineurin protein and its activity were assayed using immunoblotting and free inorganic phosphate analysis, respectively.(±)-S-nitroso-N-acetyl-penicillamine (SNAP) and Sp-8-(4-chlorophenylthio)-guanosine-3′,5′-cyclic monophosphorothioate (Sp-8-pCPT-cGMPS) decreased phenylephrine (PE)-induced proliferation of VSMC by 27.3% and 36.6%, respectively, but Rp-8-[(4-chlorophenyl)thio]-guanosine-3′,5′-cyclic monophosphorothioate (Rp-8-pCPTcGMPS) increased PE-induced proliferation of VSMC. SNAP, Sp-8-pCPT-cGMPS, and Rp-8-pCPT-cGMPS did not affect the viability of VSMC. Calcineurin protein was decreased by 63.1% and its activity was decreased by 59.7% in smooth muscle cells (SMC) pretreated with verapamil (Ver) and then stimulated by PE. In SMC pretreated with Ver, the absorbance of cells stimulated by PE decreased by 22.0% and was further inhibited by the additional treatment of SNAP and Sp-8-pCPTcGMPS. In SMC pretreated with cyclosporin A (CsA), the absorbance of cells stimulated by PE decreased by 36.7%, but could not be further altered by the additional treatment of SNAP, Sp-8-pCPT-cGMPS, and Rp-8-pCPT-cGMPS. In addition, Ver inhibited PE-induced intracellular Ca2+ variations, which could be further inhibited by SNAP and Sp-8-pCPT-cGMPS, but not by Rp-8-pCPT-cGMPS. Moreover, the increase in calcineurin activity induced by PE was inhibited by SNAP and Sp-8-pCPT-cGMPS, but was promoted by Rp-8-pCPT-cGMPS.NO/PKG regulates calcineurin activity via the modulation of intracellular Ca2+ concentration, and thus partially inhibits the proliferation of VSMC without affecting their viability. [ABSTRACT FROM AUTHOR]

As the increment of services with same function and different QoS in the internet,in order to select and rank the services that fulfill users’ functionality requirements and QoS requirements,a multi-strategy QoS-aware service ranking and selection approach is presented.Considering service performance,and service operation,maintenance costs,an extended Web service QoS model was developed.To determine how well a service satisfies users’and operators’ concerned QoS requirements,a set of functions is presented to normalize services’QoS on various QoS aspects with different metrics and scales,also to compute services satisfaction scores ,and to combine the users’satisfaction scores and the operators’scores together as an overall satisfaction scores based on certain strategy.A prototype system was built for service selection and ranking,and the model above was verified through an application case.

C-boivinopyranosyl flavones have rarely been isolated from nature. In the search for anti-HBV (hepatitis b virus) constituents of Alternanthera philoxeroides, two new compounds, luteolin-6-C-β-d-boivinopyranosyl-3′-O-β-d-glucopyranoside (1) and chrysoeriol-6-C-β-d-boivinopyranosyl-4′-O-β-d-glucopyranoside (2), along with three known C-boivinopyranosyl flavones (compounds 3–5) were isolated. Their structures were determined by spectroscopic analyses including 1D and 2D NMR, HR-ESI-MS, IR spectra. Compounds 1, 2 and 3 showed significant anti-HBV activities through specifically inhibiting the secretion of HBsAg in HepG2.2.15.