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In this paper, eleven high-strength steel tube confined self-stressing concrete (HSTCSC) short columns were tested to study their strengthening mechanism and axial compression performance. The effects of different material strengths, cross-section types, and hollow ratios on the axial mechanical properties of the HSTCSC short columns were investigated using the finite element analysis method. Experimental results highlighted that the HSTCSC short columns presented the waist drum-type failure mode significantly, with a higher axial load-bearing capacity and deformation performance, and possess a large safety reserve. It was also found that the axial compression property of the HSTCSC short column could be improved significantly due to the joint action of the micro-expansion of the self-stressing concrete and the hoop constraint of the high-strength steel tube. Moreover, the circular cross-section HSTCSC short columns were found to result in better mechanical performance after yielding of the high-strength steel tubes, especially entering the strengthening section. Under the condition of equal steel content ratio and cross-section area, the single-layer circular HSTCSC short columns were found to have the largest load-bearing capacities after yielding the high-strength steel tubes, followed by the double-layer circular HSTCSC short columns, and then the double-layer square HSTCSC short columns. The hollow rate of the cross-section could also decrease the load-bearing capacity of the HSTCSC short column with both circular and square sections, although increasing the hollow rate could save material and reduce the weight of the structure. The finite element analysis results showed that the proposed finite element model could be employed to simulate the compressive behavior of HSTCSC short columns with high calculation accuracy.

Numerical research is conducted to investigate the effects of plasma boundary shape on the tearing mode triggering explosive bursts in toroidal tokamak plasmas. In this work, m/n = 2/1 mode is responsible for the triggering of the explosive burst. Plasma boundary shape can be adjusted via the adjustment of the parameters triangularity δ and elongation κ. The investigations are conducted both under low β (close to zero) and under finite β regimes. In the low β regime, triangularity and elongation both have stabilizing effect on the explosive burst and the stabilizing effect of elongation is stronger. Under a large elongation (κ = 2.0), the elongation effect can evidently enhance the stabilizing effect in a positive triangularity regime, but barely affects the stabilizing effect in a negative triangularity regime. In the finite β regime, the explosive burst is delayed in comparison with that in the low β regime. Similar to the low β cases, the effects of triangularity and elongation both are stabilizing. Under a large elongation (κ = 2.0), the elongation effect can evidently enhance the stabilizing effect on the explosive burst in a positive triangularity regime, but impair the stabilizing effect in a negative triangularity regime. The explosive burst disappears in the large triangularity case (δ = 0.5), indicating that the explosive burst can be effectively prevented in experiments via carefully adjusting plasma boundary shape. Moreover, strong magnetic stochasticity appears in the negative triangularity case during the nonlinear phase.

Background Coronary distensibility index (CDI), as an early predictor of cardiovascular diseases, has the potential to complement coronary computed tomography angiography (cCTA)-derived fractional flow reserve (CT-FFR) for predicting major adverse cardiac events (MACEs). Thus, the prognostic value of CT-FFR combined with CDI for MACEs is worth exploring. Methods Patients with a moderate or severe single left anterior descending coronary artery stenosis were included and underwent FFR and CDI analysis based on cCTA, followed up at least 1 year, and recorded MACEs. Multivariate logistic regression analysis was performed to determine independent predictors of MACEs. The area under of receiver operating characteristic (ROC) curve was used to evaluated evaluate the diagnostic performance of CT-FFR, CDI, and a combination of the two. Results All the vessel-specific data were from LAD. 150 patients were analysed. 55 (37%) patients experienced MACEs during follow-up. Patients with CT-FFR ≤ 0.8 had higher percentage of MACEs compared with CT-FFR > 0.8 (56.3% vs.7.3%, p p p = 0.025), triglyceride (p = 0.015), CT-FFR ≤ 0.80 (p = 0.038), and CDI (p p = 0.0002). Conclusion Our study provides initial evidence that combining CDI with CT-FFR shows incremental discriminatory power for MACEs over CT-FFR alone, independent of clinical risk factors. Diabetes and triglyceride are also associated with MACEs.

Objective This paper proposes a new photoacoustic computed tomography (PACT) imaging system employing dual ultrasonic transducers with different frequencies. When imaging complex biological tissues, photoacoustic (PA) signals with multiple frequencies are produced simultaneously; however, due to the limited bandwidth of a single-frequency transducer, the received PA signals with specific frequencies may be missing, leading to a low imaging quality. Methods In contrast to our previous work, the proposed system has a compact volume as well as specific selection of the detection center frequency of the transducer, which can provide a comprehensive range for the detection of PA signals. In this study, a series of numerical simulation and phantom experiments were performed to validate the efficacy of the developed PACT system. Results The images generated by our system combined the advantages of both high resolution and ideal brightness/contrast. Conclusion The interchangeability of transducers with different frequencies provides potential for clinical deployment under the circumstance where a single frequency transducer cannot perform well.

Evaluating the impacts of human activity on river runoff has important implications for regional water resource management. Here, we used seven tree-ring width chronologies to establish a regional mean tree-ring width chronology from the northern mountain of Delingha, Qaidam Basin. We conducted the correlation, moving correlation and regression analysis of regional mean tree-ring width chronology with runoff data from Bayin River gauge station. Then, we stimulated the June runoff of Bayin River from 1956 to 2002. The results showed that the highest correlation coefficient was found for June runoff (评估人类活动对径流的影响,对区域水资源开发管理有借鉴和指导意义。利用柴达木盆地北部山区7个祁连圆柏树轮宽度数据,建立区域平均树轮宽度年表。通过对区域平均树轮宽度年表与巴音河水文站径流量进行相关、滑动相关和回归分析,模拟了巴音河1956—2002年6月天然径流量变化,进而分析出人类活动对径流量的影响。结果表明: 树轮平均年表与6月径流量的相关性最强(

The surface modification of polyacrylonitrile (PAN) fibers with boric acid was utilized to modulate the homogeneity of the radial structure of the PAN fibers during thermal stabilization. Exothermic peaks of the fibers were put off by boric acid, and unreacted nitrile groups of the oxidized PAN fibers increased with the boron content, indicating that boric acid on the fiber surface had an retardant effect on the thermal stabilization of PAN fibers. The relative skin thicknesses of the oxidized PAN fibers were quantitatively measured by sulfuric acid etching and SEM observation. The value increased obviously with the boron content, which could be further elevated by increasing stabilization time or decreasing stabilization temperature. Oxidized PAN fibers with more homogeneous radial structure can thus be obtained with the modification of boric acid, which might be beneficial for the preparation of high performance carbon fibers.

Based on Revit BIM platform and geotechnical exploration borehole data, a method to obtain arbitrary profile data of geological body is proposed. The extraction of attribute data such as profile and lithology of 3D geological body and arbitrary angle cutting plane is realized in the form of plug-in, and the input function of slope stability analysis parameters is developed on the basis of profile model.

Based on the investigation data of geotechnical engineering, aiming at the problem that the large-scale linear engineering survey data can not be expressed visually, the modeling method and modeling flow of 3D geological model are summarized. The preliminary modeling of topography, bad geological structure and stratum entity based on Civil 3D platform is realized, especially the establishment of landslide and debris flow model in bad geological structure. At the same time, the rapid modeling method of roadbed and tunnel based on Civil 3D component editor is studied.

Background Vein graft restenosis (VGR), which appears to be caused by dyslipidemia following vascular transplantation, seriously affects the prognosis and long-term quality of life of patients. Methods This study analyzed the genetic data of restenosis (VGR group) and non-stenosis (control group) vessels from patients with coronary heart disease post-vascular transplantation and identified hub genes that might be responsible for its occurrence. GSE110398 was downloaded from the Gene Expression Omnibus database. A repeatability test for the GSE110398 dataset was performed using R language. This included the identification of differentially expressed genes (DEGs), enrichment analysis via Metascape software, pathway enrichment analysis, and construction of a protein–protein interaction network and a hub gene network. Results Twenty-four DEGs were identified between VGR and control groups. The four most important hub genes ( KIR6.1, PCLP1, EDNRB, and BPI) were identified, and Pearson’s correlation coefficient showed that KIR6.1 and BPI were significantly correlated with VGR. KIR6.1 could also sensitively predict VGR (0.9 Conclusion BPI and KIR6.1 were differentially expressed in vessels with and without stenosis after vascular transplantation, suggesting that these genes or their encoded proteins may be involved in the occurrence of VGR.

Large burst activity, identified as toroidal Alfvén eigenmode (TAE) avalanche, occurs frequently in neutral-beam heated plasmas in National Spherical Torus Experiment (NSTX). Based on the typical experimental observation of TAE avalanche on NSTX, a self-consistent nonlinear multiple wave-number (k ∥ ≃ n/R, where n toroidal mode-number and R major radius) simulation associated with TAE avalanches is performed using the experimental parameters and profiles before the occurrence of TAE avalanche as the M3D-K input. The wave–wave nonlinear coupling among different modes and the resonant interaction between different modes and energetic-ions during TAE avalanches are identified in the nonlinear multiple wave-number simulations. The resonance overlap during the TAE avalanche is clearly observed in the simulation. It is found that the effective wave–wave coupling and a sufficiently strong drive are two important ingredients for the onset of TAE avalanches. TAE avalanche is considered to be a strongly nonlinear process and it is always accompanied by the simultaneous rapid frequency-chirping and large amplitude bursting of multiple modes and significant energetic-ion losses. The experimental phenomenon is observed on NSTX and is qualitatively reproduced by the simulation results in this work. These findings indicate that the onset of avalanche is triggered by nonlinearity of the system, and are also conducive to understanding the underlying mechanism of avalanche transport of energetic particles in the future burning plasmas, such as International Thermonuclear Experiment Reactor.

Background: Glioma, as the most common aggressive malignant tumor in the central nervous system, is still an insurmountable disease in neural system. The potential mechanism of its carcinogenesis remains largely unclear. Methods: In the present study, we identified dysregulated lncRNA solute carrier family 8 member A1 antisense RNA 1 (SLC8A1-AS1) as associated with glioma based on The Cancer Genome Atlas （TCGA）data. Validation experiment was conducted to confirm a high expression level of lncRNA SLC8A1-AS1 in glioma tissues. Results: Down-regulation of lncRNA SLC8A1-AS1 suppressed proliferation, clone formation, migration and invasion of glioma cells in vitro and in vivo. Moreover, lncRNA SLC8A1-AS1 silencing decreased the activity of the Wnt/β-catenin pathway and suppressed the epithelial to mesenchymal transition (EMT) in glioma cells. Conclusions: Collectively, these findings provide a novel insights into the function and mechanism of lncRNA SLC8A1-AS1 in the pathogenesis of glioma and highlight its potential as a therapeutic target for glioma intervention.

Background We studied the characteristics and regularity of appropriate insertion points for percutaneous pedicle screw placement in the lumbar spine using C-arm X-ray fluoroscopy. The purpose of this study was to improve the accuracy of percutaneous pedicle screw placement and reduce the incidence of superior-level facet joint violation. Methods Six normal spinal specimens were included. Three different methods for placing percutaneous pedicle screws in the lumbar spine were applied, including the Roy-Camille method, Magerl method and Weinstein method. The relationships among the insertion point, pedicle projection and proximal facet joint on C-arm X-ray films were studied. The projection morphology of the vertebral pedicle in different segments of the lumbar spine was observed. The relationship between the outer edge of the pedicle projection and the outer edge of the cranial articular process was also studied. The distance between the insertion point and the facet joint (M1), the distance between the insertion point and outer edge of the cranial articular process (M2), and the distance between the insertion point and the projection center of the pedicle (M) were measured. Results In this study, we found that the projection shape of the vertebral pedicle differed across segments of the lumbar spine: the shape for L1-L3 was oval, and that for L4-L5 was round. The radiographic study showed that the outer edge of the cranial articular process was located on the lateral side of the outer edge of the pedicle projection and did not overlap with the pedicle projection. M for the Weinstein group was larger than that for the Roy-Camille group (P P Conclusion Under C-arm X-ray fluoroscopy, we were able to accurately identify the characteristics and regularity of the appropriate insertion point for percutaneous pedicle screw placement in the lumbar spine, which was important for improving the accuracy of percutaneous pedicle screw placement and reducing the incidence of superior-level facet joint violation.

A full understanding of RNA-mediated biology would require the knowledge of three-dimensional (3D) structures, structural flexibility and stability of RNAs. To predict RNA 3D structures and stability, we have previously proposed a three-bead coarse-grained predictive model with implicit salt/solvent potentials. In this study, we will further develop the model by improving the implicit-salt electrostatic potential and involving a sequence-dependent coaxial stacking potential to enable the model to simulate RNA 3D structure folding in divalent/monovalent ion solutions. As compared with the experimental data, the present model can predict 3D structures of RNA hairpins with bulge/internal loops (, 24 pages,8 figures

To observe the open angle (OA), cervical curvature angle (CA), preoperative spinal cord compression rate(PSCR), postoperative spinal cord shift (PSCS) in patients with chronic compressive cervical myelopathy undergoing C3-7 single open laminoplasty, and to explore the possible mechanism and influencing factors of postoperative average spinal cord drift, so as to provide objective basis for predicting PSCS.From May 2012 to July 2016, 32 patients with multi-segmental chronic compressive cervical myelopathy who underwent single-door laminoplasty in our department were analyzed retrospectively, including 14 cases of cervical spondylotic myelopathy, 8 cases of developmental cervical spinal stenosis with cervical myelopathy, and 10 cases of ossification of posterior longitudinal ligament. The OA of cervical spine was measured on CT, the CA was measured on X-ray, the PSCR and PSCS were measured on MRI. The patients were divided into two groups according to PSCS(group A=2.5 mm, group B2.5 mm). In the group A, there were 11 males and 6 females, with an average age of (56.58±9.80) years old, a mean course of the disease of (23.52±7.86) months; while in group B, there were 6 males and 9 females, with an average age of (58.46±12.53) years old, a mean course of disease of (21.13±7.75) months. The correlation analysis between PSCS and OA, CA and PSCR was performed, and multiple linear analysis of correlated parameters was carried out.The OA in group A was (40.47±9.45) °, in group B was (27.84±5.67) °. The OA in group A was higher than that in group B (PSCS is the result of OA, CA and PSCR, among which PSCR has the most important influence, OA is the second, CA is the least. PSCS can be predicted by 0.059×OA+0.113×PSCR-2.266 equation, which provides a theoretical basis for preoperative evaluation of spinal cord decompression after surgery.

To explore the influencing factors and possible mechanism of axial symptoms(AS) after C₃-C₇ single open-door laminoplasty in patients with chronic compression cervical myelopathy.The clinical data of 32 patients with multi-segment chronic compression cervical cord disease treated by C₃-C₇ single open-door laminectomy from May 2012 to July 2016 were retrospectively analyzed. Including cervical spondylotic myelopathy of 14 cases, developmental cervical stenosis complicated with cervical myelopathy of 8 cases, ossification of posterior longitudinal ligament(OPLL) of 10 cases. There were 17 males and 15 females, aged from 47 to 82 years old with an average of 57.46 year, the course of disease was 5 to 35 months with an average of 22.4 months. The opening angle(OA), cervical curvature angle(CA), preoperative spinal cord compression rate(PSCR) and postoperative spinal cord shift (PSCS) were recorded. After 2 weeks of surgery, determining whether occurred an AS condition according to the AS assessment criteria, the patients were divided into a axial symptom group and a non-axial symptom group, the general data and imaging parameters of the two groups were compared and the factors that may be postoperative AS were analyzed by binary Logistic regression analysis.At 2 weeks after operation, 13 patients occurred AS. There was no significant difference in gender, age and course of disease between axial symptom group and a non-axial symptom group (CA, PSCR, and PSCS are related influencing factors of AS, and PSCS is a high risk factor for AS. C₄,₅ nerve traction caused by posterior spinal movement, postoperative dural self-expansion causes greater traction of the spinal cord, excessive deformation of the cervical spinal cord causes autonomic nerve damage or necrosis that dominates blood vessels may be the pathogenesis of AS, but this is only a theoretical inference, and further improved experiment is necessary to verify it in the future.

The N-myc downstream regulated gene (Ndrg) family consists of four main members Ndrg1, 2, 3, and 4. The Ndrg genes are involved in many vital biological events including development. However, comprehensive expression patterns of this gene family during vertebrate embryogenesis remain largely unknown. Here, we analyzed the Ndrg family from the evolutionary perspective and examined the expression patterns of the Ndrg genes during Xenopus tropicalis embryogenesis. Different Ndrg family members of vertebrates are separated into different homology clusters which can be further classified into two groups and each Ndrg family member is well conserved during evolution. The temporal and spatial expression patterns of Ndrg1, 2, 3 and 4 are different during early Xenopus tropicalis development. Ndrg1, 2 and 4 are maternally expressed genes while Ndrg3 is a zygotically expressed gene. The Ndrg genes are differentially expressed in the developing central nervous system, the developing sensory organs, and the developing excretory organs. Moreover, they also show other specific expression domains. Our results indicate that the Ndrg genes exhibit specific expression patterns and may play different roles during vertebrate embryogenesis.

In our efforts to investigate the relationships between the metal ions and the structures of their complexes based on N-donor ligand, 1-(4-pyridylmethyl)-1H-benzimidazole (L), and their complexes [Ag(L)(ClO4)]n (1),{[Cu(L)2 (ClO4)2](H2O)2}n (2) were synthesized and structurally characterized by elemental analyses, IR spectra and single-crystal X-ray diffraction analysis. Structural analyses show that 1 possess one-dimensional (1D) double helix chain structure, which further forms two-dimensional supramolecular framework connected by Ag···Ag and Ag···O weak interactions. When the metal ion was changed to Cu(II), 2 was obtained, which shows a two-fold interpenetrating three-dimensional diamond network. The results show that the metal ions and weak interactions play important roles in the construction of such coordination architectures. X-ray powder diffractions show that the bulk synthesized materials and the crystals used for diffraction are homogeneous. Meanwhile, the photoluminescent property of the comp...

There are high organic matter and cation exchange capacity (CEC) in paper mill sludge, which can be used efficiently to amend soil properties and promote the growth of crops. The batch method was used to investigate effects of paper sludge on adsorption and desorption of Cd (II) and Pb (II) in two types paddy soil (red soil, purple soil), through adding paper sludge to red soil and purple soil. The results showed that isothermal sorption process of Cd (II) and Pb (II) by soils and paper sludge could be well described by Langmuir equation and Freundlich equation, and all coefficients (r) were higher than 0.9. The purple soil had a higher sorption capacity of Cd (II) and Pb (II) than red soil. The sorption capacities of Cd (II) and Pb (II) in soils increased after added paper sludge, and they reached adsorption equilibrium as the percentages of paper sludge were 10%, 1% in red soil and purple soil, respectively. The desorption capacities of Cd (II) and Pb (II) in soils decreased after added paper sludge, and they reached minimum as the percentages of paper sludge were 5%, 2% in red soil and purple soil, respectively. It was better to immobilize Cd (II) and Pb (II) after added paper sludge, thus paper mill sludge can relieve the migration of heavy metals in soil-crop systems. It can provide a new way for safe using of heavy metal contaminated soil and resource utilization of paper sludge.

Regeneration capacity varies greatly among different animal species. In vertebrate, amphibian especially the Urodela, has been used as a powerful model system to study the mechanism of tissue regeneration because of the strong ability to regenerate their damaged or lost appendages. Pachytriton brevipes, a species of newt, which is widely distributed in south of China, can completely restore their damaged limbs within several months. In this study, we use modified suppression subtractive hybridization assay and dot-blot screening to identify candidate genes involved in tissue regeneration in P. brevipes. We successfully isolated 81 ESTs from a forward regeneration subtraction library. And we further verified the differential expression of four candidate genes, Rpl11, Cirbp, Ag2 and Trimx, between regenerating blastema and non-regeneration tissues by in situ hybridization. These genes were also be further characterized by phylogenetic and bioinformatic analysis. In general, we provided a comparative experimental approach to study the mechanisms of vertebrate regeneration.

The paper presents the rutting test using cylinder specimen with flexible constraint on the basis of Chinas existing rutting tests. Through laboratory rutting tests by comparing the use of the rutting plate specimen and that of the cylinder specimen, it concludes that by the use of the latter, the specimen shape is easy to control, the variability of the rutting depth is small and the ability to distinguish asphalt mixture is equivalent to the test using the plate specimen, and proves the feasibility of using the cylinder specimen with flexible constraint to carry out laboratory rutting test.

It put forward the new technology of reinforcing tie-beam with steel plate yoke to reinforcing the bridge based on analysis the reasons of the defection of the reinforcement trussed arch bridge deeply. In the text it analysis the mechanism of the steel plate yoke on the theory of the constant improvement in the horizontal distribution and transverse pre-tensile stress designing and introduce the construction technics of the reinforcement technology particularly. It is proved that the combined reinforcing technologies are effective according to test factual bridge.

This paper summarizes the development of electronic records management, and due to current defects and shortcomings, discusses the more effective and reasonable information security management program. For the system security issues, the paper has done an overall security analysis of system from the application layer, network layer, and database layer to physical and management levels, and has made a system’s security strategy.

This paper carried research on seed rain intensity, seed rain time, the effects of sound seed input density of Castanopsis fargesii population and Castanopsis carlesii population in the Three Gorges Reservoir. The result showed that: (1) the seed production of Castanopsis carlesii and Castanopsis fargesii was low in the studied population, the seed rain was 36.5 seeds • m-2, 22.6 seeds • m-2, and the sound seed input density were 20.5 seeds • m-2, 9.6 seeds • m-2 respectively. (2) infesting and decay were the main causes of seed losing, 43.8% lost in Castanopsis carlesii population and 67.5% lost in Castanopsis fargesii population. (3) the duration of Castanopsis carlesii and Castanopsis fargesii population’s seed rain were 47days and 37 days, but there was a different top time between two populations, the seed rain peak of Castanopsis carlesii population was from middle to late November, with a distinguishable dropping peak, and the seed rain peak of Castanopsis fargesii population was from early to middle November.(4) temperature has significant effect on sound seed input density of Castanopsis carlesii population, temperature and wind speed have significant effect on sound seed input density of Castanopsis fargesii population.

In recent years, GSM communication network has developed rapidly, which has basically covered the whole country and has been improved the quality of network communication. The public communication network transmission is used GSM power equipment information, which is a power of new communication system and the distributed power equipment monitoring to achieve the new ideas. This article is based on the research and the practice, and it puts forward and develops the practical GSM network based on the master station software of distribution transformer monitoring. It is used to implement the data transmission between the serial port and the database. The module provides a common library interface to other programs that can be called directly. Distribution transformer monitoring is the main part of the master station software to develop and use the Power Builder. PowerBuilder native database is used the local relational database SQL Anywhere and the GSM distribution transformer monitoring system of the master station software is used the standard Windows interface style and modular design. The system can be used as an important part of power management, and the urban distribution network automation is also a useful addition to favorable scheduling and allocation of a reasonable load, which has the good social and economic benefit.