1,134 research outputs found

    EXPERIMENTAL STUDY AND ANALYTICAL METHOD OF PARTIALLY CONCRETE-FILLED STEEL BRIDGE PIERS UNDER BI-DIRECTIONAL DYNAMIC LOADING

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    From past large earthquake, it has been recognized that the highway steel bridge piers in urban areas play a very important role in the social lifeline system. The seismic design specification of steel bridge piers introduced in the current Japan allows independent, longitudinal, and transverse forces. To date the seismic performance of steel bridge piers has been widely studied through static cyclic loading tests, pseudo-dynamic loading tests, and numerical analysis in a single lateral direction under constant axial force. However, the actual seismic waves consist of three-directional components and the seismic response of bridge piers is simultaneously affected by the two horizontal components. It is difficult to properly evaluate the seismic performance of bi-directional horizontal seismic motions through single-directional loading tests because of the complex behavior of local buckling and inelastic behavior caused in the component plates of the pier at the ultimate state. To clarify the seismic performance of partially concrete-filled steel bridge piers subjected to bi-directional seismic loading, the performance of partially concrete-filled steel bridge piers under actual earthquake conditions was investigated using 20 square section specimens through cyclic static loading tests and single-and bi-directional hybrid loading tests in this study. Three acceleration records of two horizontal NS and EW direction components in three different ground types, obtained during the 1995 Kobe Earthquake, were adopted during the dynamic tests. The experimental results clarified that the maximum displacement and residual displacement under actual earthquake conditions cannot be correctly estimated by conventional single-directional loading test results in medium and soft ground types, and the filled-in concrete can effectively improve the seismic resistance performance in sufficiently high concrete filled steel bridge piers. In this study, an analytical model consisting of a concentrated mass and a rigid bar with multiple springs located at the base was developed to simulate the hysteretic behavior of partially concrete-filled steel bridge piers subjected to single- or bi-directional ground motions. In order to describe the complicated nonlinear behavior of each spring element accurately, a series of approximate curves whose parameters were determined by results of single-directional static cyclic loading tests had been adopted. To examine the validity of the proposed model, the results due to the simulation were compared with those of static cyclic tests, single- and bi-directional hybrid tests. By comparison, it is demonstrated that the proposed multiple-spring model can predict well the hysteretic behavior of partially concrete-filled thin-walled steel bridge piers with square cross-section

    Investigation of Noncovalent Complexes Between β-Cyclodextrin and Polyamide Acids Containing N-Methylpyrrole and N-Methylimidazole by Electrospray Ionization Mass Spectrometry

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    Electrospray ionization (ESI) mass spectrometry was utilized to investigate noncovalent complexes between β-cyclodextrin (β-CD) and five novel polyamide acids containing N-methylpyrrole and N-methylimidazole. The 1:1 binding mode was specified by examining the binding stoichiometry from ESI mass spectra. It found that polyamide acids with β-CD have binding affinities in the order: ImImImβCOOH > ImPyImβCOOH > ImPyPyβCOOH > PyPyPyβCOOH > NO2PyPyPyβCOOH. The method gives, simultaneously, the binding constants between β-CD and polyamide acids based on a novel linear equation

    Theoretical Study on Superradiant Raman Scattering with Rubidium Atoms in An Optical Cavity

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    Superradiant Raman scattering of Rubidium atoms has been explored in the experiment [Nature 484, 78 (2012)] to prove the concept of the superradiant laser, which attracts significant attentions in quantum metrology due to the expected ultra-narrow linewidth down to millihertz. To better understand the physics involved in this experiment, we have developed a quantum master equation theory by treating the Rubidium atoms as three-level systems, and coupling them with a dressed laser and an optical cavity. Our simulations show different superradiant Raman scattering pulses for the systems within the crossover and strong coupling regime, and the shifted and broader spectrum of the steady-state Raman scattering. Thus, our studies provide a unified view on the superradiant Raman scattering pulses, and an alternative explanation to the broad spectrum of the steady-state Raman scattering, as observed in the experiment. In future, our theory can be readily applied to study other interesting phenomena relying on the superradiant Raman scattering, such as magnetic field sensing, real-time tracking of quantum phase, Dicke phase transition of non-equilibrium dynamics and so on.Comment: 9 pages, 11 figure

    A Curve Approximated Hysteresis Model for Steel Bridge Columns

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    In this paper,a curve approximated hysteresis model for SDF analysis is proposed to predict the nonlinear response of bridges supported by steel columns with suitable scope of severe damaged deterioration domain. Instead of multiple straight lines,a series of curves are adopted to precisely describe complicated force-displacement hysteresis behavior of the column. The P-δ effect, hardeing effect in unloading-reloading hysteresis loops, deterioration of strength and stiffness are taken into account. Parameters of proposed hysteresis model for three types of steel pier specimens used in this study are calibrated by six static cyclic tests. To verify the accuracy of the proposed model, eleven pseudo-dynamic tests are conducted. By comparing the simulation and the test results,the differences between the predicted nonlinear seismic response using the proposed model and pseudo-dynamic tests are found to be, averagely, 5% in maximum response displacement,22% in residual displacement and 4% in the amount of energy dissipation

    Transcriptome analysis of epithelioma papulosum cyprini cells after SVCV infection

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    BACKGROUND: Spring viraemia of carp virus (SVCV) has been identified as the causative agent of spring viraemia of carp (SVC) and it has caused significant losses in the cultured common carp (Cyprinus carpio) industry. The molecular mechanisms that underlie the pathogenesis of the disease remain poorly understood. In this study, deep RNA sequencing was used to analyse the transcriptome and gene expression profile of EPC cells at progressive times after SVCV infection. This study addressed the complexity of virus–cell interactions and added knowledge that may help to understand SVCV. RESULTS: A total of 33,849,764 clean data from 36,000,000 sequence reads, with a mean read length 100 bp, were obtained. These raw data were assembled into 88,772 contigs. Of these contigs, 19,642 and 25,966 had significant hits to the NR and Uniprot databases where they matched 17,642 and 13,351 unique protein accessions, respectively. At 24 h post SVCV infection (1.0 MOI), a total of 623 genes were differentially expressed in EPC cells compared to non-infected cells, including 288 up-regulated genes and 335 down-regulated genes. These regulated genes were primarily involved in pathways of apoptosis, oxidative stress and the interferon system, all of which may be involved in viral pathogenesis. In addition, 8 differentially expressed genes (DEGs) were validated by quantitative PCR. CONCLUSIONS: Our findings demonstrate previously unrecognised changes in gene transcription that are associated with SVCV infection in vitro, and many potential cascades identified in the study clearly warrant further experimental investigation. Our data provide new clues to the mechanism of viral susceptibility in EPC cells. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/1471-2164-15-935) contains supplementary material, which is available to authorized users

    Some Results on Anonymity in Hybrid Encryption

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    Anonymity(key-privacy) as well as security(data-privacy) are all important features in public-key encryption applications. In this paper two new and general concepts, named “relevant anonymity” and “relevant security”, are defined. Based-upon these concepts some general results on anonymity in public-key encryption are proved, which fall in three categories. The first results are two general relationships between anonymity and security; the second are a sufficient and necessary condition for chosen-plaintext anonymity in Fujisaki-Okamoto hybrid construction and a sufficient condition for its chosen-ciphertext anonymity; the third is a sufficient condition for chosen-ciphertext anonymity in Okamoto-Pointcheval hybrid construction (REACT). All these conditions are also easy-to-use criteria in practice. By examples such general consequences are applied to some specific schemes and as a result anonymity of some well-known schemes are re-established in a simpler way. Furthermore, NISSIE scheme PSEC-/1/2/3’s chosen-ciphertext anonymity are proved

    The rise of urbanism and exchange network: reconstruction of a 4000-year local history of Xinjiang, northwestern China

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    Urbanization is one of the milestones in the development of human society. Many regions in the southern parts of ‘the old world’ demonstrating an early emergence of agriculture also witnessed the flourishing of some of the earliest cities. Recent, yet still sparse, archaeological evidence appears to indicate a relatively later time for early urbanism in central Eurasia. However, given its vital geographic location and cultural nexus between East and West, more attention should be paid to the sedentary communities and their cities in oases amid the vast droughty desert, particularly in light of the rapidly increasing number of publications on early pastoralism and related communication routes along mountain chains and rivers. This study reveals the trajectory of urbanization and its role in the establishment of an exchange network in Xinjiang’s oasis region via reconstruction of the chronological sequence of the local societal history of the Baiyang River Basin along the southern piedmont of the Eastern Tianshan Mountains. A thorough archaeological investigation and refined radiocarbon dating programme was carried out and coupled with information from historical documentation within a Bayesian statistical framework. The results indicate three pulses of local urbanization during: the Early Iron Age, Tang–Yuan period, and Qing Dynasty, respectively. Combining this with evidence from other parts of Xinjiang, we re-evaluate the role of oasis urbanism in the promotion of trans-regional exchange

    Insulin Resistance and Oxidative Stress: In Relation to Cognitive Function and Psychopathology in Drug-Naive, First-Episode Drug-Free Schizophrenia

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    Objective: The present study aimed to examine whether insulin resistance and oxidative stress are associated with cognitive impairment in first-episode drug-free schizophrenia (SZ) patients. Methods: Ninety first-episode SZ patients and 70 healthy controls were enrolled. Fasting insulin (FINS) and markers of oxidative stress [oxidized glutathione (GSSG), superoxide dismutase (SOD), nitric oxide (NO) and uric acid (UA) levels] were measured in serum before pharmacological treatment was initiated. Psychiatric symptoms and cognitive function were assessed with the Positive and Negative Syndrome Scale (PANSS) and MATRICS Consensus Cognitive Battery (MCCB), respectively. In addition, the homeostatic model assessment of insulin resistance (HOMA-IR) was also studied. Results: HOMA-IR and serum levels of GSSG and NO were significantly higher in SZ patients than in healthy controls (P \u3c 0.001), while the serum levels of SOD were significantly lower than in healthy controls (P \u3c 0.001). HOMA-IR, GSSG and NO levels were significantly correlated to the total cognitive function scores of the patient group (r = -0.345,-0.369,-0.444, respectively, P \u3c 0.05). But these factors were not co-related to the cognitive functions in the healthy control group. And, levels of SOD, UA were not associated with the total cognitive function scores in both the patient and the healthy control groups. NO was positively correlated with general pathological and the total score in the PANSS, and was negatively correlated with six cognitive domains (r = -0.316 to -0.553, P \u3c 0.05). Conclusions: The levels of insulin resistance and oxidative stress are elevated, and correlated with the severity of cognitive impairment in drug-naive, first-episode SZ patients. Treatment approaches targeting on reducing insulin resistance and oxidative stress may improve cognitive function in SZ patients

    The influence of gold mining wastes on the migration-transformation behavior and health risks of arsenic in the surrounding soil of mined-area

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    Understanding the characteristic heavy metals and their migration-transformation behavior in mining areas is essential for the prevention and control of mining pollution. This study selected a gold mine in the Anqing-Guichi ore-cluster region in the Middle-Lower Yangtze metallogenic belt as the research area, the concentrations, and migration-transformation mechanisms of metalloid As and typical heavy metals (Cd, Zn, Pb, Cu, Cr, and Ni) in gold mining wastes (mine tailings and sewage sludge) and the surrounding soil (farmland soil and soil a mining area) were investigated. The results showed that the concentration of As was high in both mining wastes and soils, and the geo-accumulation index values of As in soils ranging from 1.44–6.70, indicated that As pollution was severe in the soil. Besides, a close correlation between the concentration of As and the content of iron was observed by XRF analysis, in conjunction with SEM observations, most As-bearing phases are embedded in Fe, O, and Si compounds. According to EDS and XPS results, the Fe-O-As particle was suggested to be Fe-(oxy)hydroxides with absorbed or co-precipitated As. Furthermore, the arsenic phase observed in the soils were consistent with the weathering oxidation products in the tailings, demonstrating that the mineral particles in the tailings could migrate into soils via atmospheric transport, rainwater leaching, surface runoff, etc., and consequently result in heavy metal accumulation. The sequential chemical extraction result showed that the residual state of As in the soil exceeded 60%, and As posed no risk to low risk according to the Risk assessment code result. However, due to the high concentration and high mobility of arsenic, its environmental impact cannot be ignored even if its bio-accessibility in mined area soil is low

    A Truncated IL‐17RC Peptide Ameliorates Synovitis and Bone Destruction of Arthritic Mice

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134880/1/adhm201600668_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134880/2/adhm201600668-sup-0001-S1.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/134880/3/adhm201600668.pd
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