2,930 research outputs found

    Self-organization and phase transition in financial markets with multiple choices

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    Market confidence is essential for successful investing. By incorporating multi-market into the evolutionary minority game, we investigate the effects of investor beliefs on the evolution of collective behaviors and asset prices. When there exists another investment opportunity, market confidence, including overconfidence and under-confidence, is not always good or bad for investment. The roles of market confidence is closely related to market impact. For low market impact, overconfidence in a particular asset makes an investor become insensitive to losses and a delayed strategy adjustment leads to a decline in wealth, and thereafter, one's runaway from the market. For high market impact, under-confidence in a particular asset makes an investor over-sensitive to losses and one's too frequent strategy adjustment leads to a large fluctuation in asset prices, and thereafter, a decrease in the number of agents. At an intermediate market impact, the phase transition occurs. No matter what the market impact is, an equilibrium between different markets exists, which is reflected in the occurrence of similar price fluctuations in different markets. A theoretical analysis indicates that such an equilibrium results from the coupled effects of strategy updating and shift in investment. The runaway of the agents trading a specific asset will lead to a decline in the asset price volatility and such a decline will be inhibited by the clustering of the strategies. A uniform strategy distribution will lead to a large fluctuation in asset prices and such a fluctuation will be suppressed by the decrease in the number of agents in the market. A functional relationship between the price fluctuations and the numbers of agents is found

    Data Processing Pipeline for Pointing Observations of Lunar-based Ultraviolet Telescope

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    We describe the data processing pipeline developed to reduce the pointing observation data of Lunar-based Ultraviolet Telescope (LUT), which belongs to the Chang'e-3 mission of the Chinese Lunar Exploration Program. The pointing observation program of LUT is dedicated to monitor variable objects in a near-ultraviolet (245-345 nm) band. LUT works in lunar daytime for sufficient power supply, so some special data processing strategies have been developed for the pipeline. The procedures of the pipeline include stray light removing, astrometry, flat fielding employing superflat technique, source extraction and cosmic rays rejection, aperture and PSF photometry, aperture correction, and catalogues archiving, etc. It has been intensively tested and works smoothly with observation data. The photometric accuracy is typically ~0.02 mag for LUT 10 mag stars (30 s exposure), with errors come from background noises, residuals of stray light removing, and flat fielding related errors. The accuracy degrades to be ~0.2 mag for stars of 13.5 mag which is the 5{\sigma} detection limit of LUT.Comment: 10 pages, 7 figures, 4 tables. Minor changes and some expounding words added. Version accepted for publication in Astrophysics and Space Science (Ap&SS

    Tetra­aqua­(2,2′-bipyridine-κ2 N,N′)magnesium(II) bis­(4-fluoro­benzoate)

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    The title compound, [Mg(C10H8N2)(H2O)4](C7H4FO2)2, consists of a bivalent [Mg(C10H8N2)(H2O)4]2+ cation and two 4-fluorbenzoate anions. In the complex cation, the MgII atom is coordinated by two N atoms from a 2,2′-bipyridine ligand and four water O atoms in a distorted MgN2O4 octa­hedral geometry. The MgII atom is located on a twofold rotation axis and thus a cation exhibits C 2 mol­ecular symmetry. The 2,2′-bipyridine ligands exhibit nearly perfect planarity (r.m.s. deviations = 0.0061 Å). In the crystal, O—H⋯O and C—H⋯O hydrogen bonds link the cations and anions into a three-dimensional supra­molecular network

    Abnormal magnetoresistance behavior in Nb thin film with rectangular antidot lattice

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    Abnormal magnetoresistance behavior is found in superconducting Nb films perforated with rectangular arrays of antidots (holes). Generally magnetoresistance were always found to increase with increasing magnetic field. Here we observed a reversal of this behavior for particular in low temperature or current density. This phenomenon is due to a strong 'caging effect' which interstitial vortices are strongly trapped among pinned multivortices.Comment: 4 pages, 2 figure

    Recent advances in double-lumen tube malposition in thoracic surgery: A bibliometric analysis and narrative literature review

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    Thoracic surgery has increased drastically in recent years, especially in light of the severe outbreak of the 2019 novel coronavirus disease (COVID-19). Routine “passive” chest computed tomography (CT) screening of inpatients detects some pulmonary diseases requiring thoracic surgeries timely. As an essential device for thoracic anesthesia, the double-lumen tube (DLT) is particularly important for anesthesia and surgery. With the continuous upgrading of the DLTs and the widespread use of fiberoptic bronchoscopy (FOB), the position of DLT in thoracic surgery is gradually becoming more stable and easier to observe or adjust. However, DLT malposition still occurs during transferring patients from a supine to the lateral position in thoracic surgery, which leads to lung isolation failure and hypoxemia during one-lung ventilation (OLV). Recently, some innovative DLTs or improved intervention methods have shown good results in reducing the incidence of DLT malposition. This review aims to summarize the recent studies of the incidence of left-sided DLT malposition, the reasons and effects of malposition, and summarize current methods for reducing DLT malposition and prospects for possible approaches. Meanwhile, we use bibliometric analysis to summarize the research trends and hot spots of the DLT research

    Abnormal magnetoresistance behavior in Nb thin film with rectangular antidot lattice

    Full text link
    Abnormal magnetoresistance behavior is found in superconducting Nb films perforated with rectangular arrays of antidots (holes). Generally magnetoresistance were always found to increase with increasing magnetic field. Here we observed a reversal of this behavior for particular in low temperature or current density. This phenomenon is due to a strong 'caging effect' which interstitial vortices are strongly trapped among pinned multivortices.Comment: 4 pages, 2 figure

    Emission dynamics of GaN-based blue resonant-cavity light-emitting diodes

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    Abstract(#br)We fabricated GaN-based blue resonant-cavity light-emitting diodes (RCLEDs) by inserting InGaN quantum well (QW) active region between two dielectric distributed Bragg reflectors (DBRs). Due to the different gain enhancement factors in a single device, multi-longitudinal modes were observed and tuned with changing the injection current density: pure-blue (PB) at low current density, violet-blue (VB) at intermediate current density, and PB again at high current density. The variation of emission spectra is explained by the competition between band-filling effect and self-heating effect

    Curative Effects of ZHENG-Based Fuzheng-Huayu Tablet on Hepatitis B Caused Cirrhosis Related to CYP1A2 Genetic Polymorphism

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    Aim. To investigate the correlation of Fuzheng-Huayu tablet (FZHY) efficacy on chronic hepatitis B caused cirrhosis (HBC) and single nucleotide polymorphisms (SNPs) of CYP1A2. Methods. After 111 cases of HBC with 69 excess, 21 deficiency-excess, and 21 deficiency ZHENGs (ZHENG, also called traditional Chinese medicine syndrome) were treated by FZHY for 6 months, clinical symptoms, Child-Pugh score, and ZHENG score were observed. Three of the SNPs in CYP1A2 gene were detected and analyzed using SNaPshot assay. Results. In ZHENG efficacy between effective and invalid groups, there was significant difference (P<0.001). The ZHENG deficiency was significantly correlated with FZHY efficacy (P<0.05). AA genotype of CYP1A2-G2964A was significantly different with GG genotype (P<0.05) between CYP1A2 Genotypes and FZHY efficacy on ZHENG. More importantly, GA plus AA genotype of CYP1A2-G2964A was significantly different with deficiency ZHENG (P<0.05) between CYP1A2 genotypes and FZHY efficacy on ZHENG. Conclusion. FZHY improved ZHENG score of HBC, and these efficacies may relate to CYP1A2-G2964A sites. It was suggested that CYP1A2-G2964A locus is probably a risk factor for ZHENG-based FZHY efficacy in HBC
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