Behaviour and design of high strength steel homogeneous and hybrid welded I-section beams

The behaviour and design of high strength steel (HSS) beams are addressed in the present study. Six in-plane three-point bending tests on three different welded I-sections − two homogeneous S690 steel welded I-sections and one hybrid welded I-section with S690 steel flanges and an S355 steel web, were first conducted. The beam tests were carried out in major axis bending and a bespoke restraint system was designed and employed in the test programme to prevent lateral-torsional buckling. Following the experimental investigation, a thorough finite element (FE) modelling programme was performed, which included a validation study confirming the accuracy of the developed FE models in replicating the flexural behaviour of HSS welded I-section beams, and a parametric study generating additional FE data on HSS welded I-section beams over a broader range of cross-sectional slendernesses, steel grades and loading configurations. The test results obtained in the present study and collected from the literature, together with the generated FE data from the parametric study, were used to evaluate the suitability of the current Eurocode 3 cross-section slenderness limits for HSS homogeneous and hybrid welded I-sections in bending. It is shown that the current Eurocode Class 2 and Class 3 slenderness limits are suitable for the classification of the outstand flange (in compression) and internal web (in bending) elements of both HSS homogeneous and hybrid welded I-sections subjected to major axis bending, while stricter Class 1 slenderness limits are considered necessary to achieve sufficient rotation capacity for plastic design. The findings from the present study indicate that plastic design can be used for HSS structures, provided the proposed stricter Class 1 slenderness limits are employed

Comment on "Single-mode excited entangled coherent states"

In Xu and Kuang (\textit{J. Phys. A: Math. Gen.} 39 (2006) L191), the authors claim that, for single-mode excited entangled coherent states $| \Psi_{\pm}(\alpha,m)>$, \textquotedblleft the photon excitations lead to the decrease of the concurrence in the strong field regime of $| \alpha | ^{2}$ and the concurrence tends to zero when $| \alpha | ^{2}\to \infty$". This is wrong.Comment: 4 apges, 2 figures, submitted to JPA 15 April 200

Analysis of Controlling Genes for Tiller Growth of \u3cem\u3ePsathyrostachys juncea\u3c/em\u3e Based on Transcriptome Sequencing Technology

Tillering is an important trait of bunch grass that affects biomass and seed yield. Psathyrostachys juncea is a typical perennial bunch grass, and unraveling the regulatory mechanisms of tillering in P. juncea could be helpful to improve the yield of perennial gramineous forages. Hence, we selected the tiller node of P. juncea for transcriptome sequencing to determine the differentially expressed genes (DEG) between high and low tillering materials. The metabolic pathway was studied，candidate genes were screened, and reference genes stability were evaluated. The results showed that approximately 5466 DEGs were identified between two P. juncea genotypes that significantly differed in tiller number. Pathway enrichment analysis indicated that DEGs related to the biosynthesis of three classes of phytohormones, i.e., strigolactones (SLs), auxin (IAA), and cytokinin (CTK), as well as “nitrogen metabolism” and “biosynthesis of lignin” dominated the differences between the dense and sparse tillering genotypes. Meanwhile, the reference gene Actin1, having with the best stability, was screened from twelve highest expression level genes and was used in verification of ten tillering candidate genes. The candidate genes revealed in our research are involved in the regulation of tillering in perennial grasses and are available for new breeding resources establishment for high-yield perennial grasses

A Fair and Secure Cluster Formation Process for Ad Hoc Networks

An efficient approach for organizing large ad hoc networks is to divide the nodes into multiple clusters and designate, for each cluster, a clusterhead which is responsible for holding intercluster control information. The role of a clusterhead entails rights and duties. On the one hand, it has a dominant position in front of the others because it manages the connectivity and has access to other node¿s sensitive information. But on the other hand, the clusterhead role also has some associated costs. Hence, in order to prevent malicious nodes from taking control of the group in a fraudulent way and avoid selfish attacks from suitable nodes, the clusterhead needs to be elected in a secure way. In this paper we present a novel solution that guarantees the clusterhead is elected in a cheat-proof manner

A study on the extraction and purification technology of tea sapogenin

In order to extract and purify tea sapogenin, first the extraction liquid is obtained using mechanically pressed tea-seeds as raw material, which will be decreased by organic solvent. When the conditions like the methanol volume fraction is 75v/v, solid-liquid is 1:4 and the ultrasonic frequency is 25.8 Hz, extract them for 30 min. After this, collect the extraction liquid and slowly add in Hz-841 macroporous resin column, then elute it with 0.3% NaOH. The third step is to elute with ethanol of different concentrations after the coloring pigment is got rid of, and then detect it with thin layer chromatography (TLC). It is discovered that there is only tea sapogenin in the 35 – 95v/v ethanol elution liquid. The last step is to collect the 95% ethanol elution liquid and vacuum condense it; and then tea-Tea sapogenin with a purity of 96% can be obtained

Dynamical Evolution of Interacting Modified Chaplygin Gas

The cosmological model of the modified Chaplygin gas interacting with cold dark matter is studied. Our attention is focused on the final state of universe in the model. It turns out that there exists a stable scaling solution, which provides the possibility to alleviate the coincidence problem. In addition, we investigate the effect of the coupling constants $c_{1}$ and $c_{2}$ on the dynamical evolution of this model from the statefinder viewpoint. It is found that the coupling constants play a significant role during the dynamical evolution of the interacting MCG model. Furthermore, we can distinguish this interacting model from other dark energy models in the $s-r$ plane.Comment: 10 pages, 6 figures, accepted for publication in Int. J. Mod. Phys.

Rigidity of minimal submanifolds in hyperbolic space

We prove that if an $n$-dimensional complete minimal submanifold $M$ in hyperbolic space has sufficiently small total scalar curvature then $M$ has only one end. We also prove that for such $M$ there exist no nontrivial $L^2$ harmonic 1-forms on $M$

Local infiltration analgesia versus femoral nerve block in total knee arthroplasty: A meta-analysis

AbstractIntroductionLocal infiltration analgesia (LIA) and femoral nerve block (FNB) are both used for the pain management after total knee arthroplasty (TKA). Controversy still remains regarding the optimal technique for pain relief in patients undergoing TKA. The purpose of this meta-analysis was to compare the analgesia achieved with LIA and the one from FNB following TKA.HypothesisLIA achieves better pain control than FNB in patients with TKA.MethodsDatabases, including Pubmed, EMBASE, the Cochrane Library and Web of Science were comprehensively searched to identify studies comparing LIA with FNB for patients with TKA. Two reviewers independently selected trials, extracted data, and assessed the methodological qualities of included studies. Data were analyzed by RevMan 5.2.ResultsNine RCTs involving 782 patients were included. LIA achieved more rapid pain relief (VAS) at 6h postoperatively [SMD6h=−0.92, 95% CI (−1.38, −0.47)] than FNB. There were no significant differences at 24h and 48h [SMD24h=−0.03, 95% CI (−0.46, 0.40); SMD48h=0.28, 95% CI (−0.35, 0.91)], VAS with activity at 24h and 48h [SMD6h=−0.54, 95% CI (−1.62, 0.54); SMD24h=−0.22, 95% CI (−1.41, 0.96); SMD48h=−0.08, 95% CI (−0.52, 0.69)], opioid consumption at 24h and 48h [SMD24h=−0.24, 95% CI (−0.82, 0.34); SMD48h=0.15, 95% CI (0.25, 0.54)] and length of hospital stay [MD=−0.52, 95% CI (−1.13, 0.09)].DiscussionLIA may be the better choice in the pain management of TKA for it could achieve fast pain relief and is easier to perform than FNB for patients with TKA.Level of evidenceLevel II, meta-analysis and systematic review