1,682 research outputs found

    Transverse Velocity Field Measurement in High-Resolution Solar Images Based on Deep Learning

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    To address the problem of the low accuracy of transverse velocity field measurements for small targets in high-resolution solar images, we proposed a novel velocity field measurement method for high-resolution solar images based on PWCNet. This method transforms the transverse velocity field measurements into an optical flow field prediction problem. We evaluated the performance of the proposed method using the Ha and TiO datasets obtained from New Vacuum Solar Telescope (NVST) observations. The experimental results show that our method effectively predicts the optical flow of small targets in images compared with several typical machine- and deep-learning methods. On the Ha dataset, the proposed method improves the image structure similarity from 0.9182 to 0.9587 and reduces the mean of residuals from 24.9931 to 15.2818; on the TiO dataset, the proposed method improves the image structure similarity from 0.9289 to 0.9628 and reduces the mean of residuals from 25.9908 to 17.0194. The optical flow predicted using the proposed method can provide accurate data for the atmospheric motion information of solar images. The code implementing the proposed method is available on https://github.com/lygmsy123/transverse-velocity-field-measurement.Comment: 14 pages, 10 figures, 4 tables. Accepted for publication in Research in Astronomy and Astrophysic

    Potential effectiveness of traditional Chinese medicine for cardiac syndrome X (CSX): a systematic review and meta-analysis

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    BACKGROUND: Treatment of cardiac syndrome X with unknown pathological mechanism remains a big challenge for clinicians. Complementary and alternative medicine may bring a new choice for its management. The aim of this study is to evaluate the clinical effects of traditional Chinese medicine on cardiac syndrome X patients. METHODS: We systematically searched databases such as Cochrane CENTRAL, PubMed, EMBASE, CBM, Chinese National Knowledge Infrastructure (CNKI), WanFang and VIP, and handsearched relevant journals to identify randomized controlled trials. Following the steps of systematic review recommended by the Cochrane group, we assessed the quality of included studies, extracted valid data and undertook meta-analysis. RESULTS: Twenty one moderate-to low-quality randomized controlled trials involving 1143 patients were included. The results showed that traditional Chinese medicine could improve angina [OR=1.34, 95% CI: 1.2 to 1.50], electrocardiogram (ECG), endothelin-1 (ET-1) levels, prolong exercise duration in treadmill tests, and reduce angina frequency per week compared with routine treatment. No other side effect was reported except two cases of stomach pain. CONCLUSION: Compared with conventional treatment, traditional Chinese medicine shows the potential of optimizing symptomatic outcomes and improving ECG and exercise duration. The efficacy of TCM may find explanation in its pharmacological activity of adjusting the endothelial function. TCM, as a kind of alternative and complementary medicine, may provide another choice for CSX patients

    High-temperature high-sensitivity AlN-on-SOI Lamb wave resonant strain sensor

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    A piezoelectric AlN-on-SOI structured MEMS Lamb wave resonator (LWR) is presented for high-temperature strain measurement. The LWR has a composite membrane of a 1 Ī¼m thick AlN film and a 30 Ī¼m thick device silicon layer. The excited acoustic waves include Rayleigh wave and Lamb waves. A tensile strain sensor has been prepared with one LWR mounted on a uniaxial tensile plate, and its temperature characteristics from 15.4Ā°C to 250Ā°C and tensile strain behaviors from 0 Ī¼Ļµ to 400 Ī¼Ļµ of Rayleigh wave and S4 mode Lamb wave were tested. The temperature test verifies the adaptability of the tensile strain sensor to temperature up to 250Ā°C, and S4 mode Lamb wave and Rayleigh wave represent almost the same temperature characteristics. The strain test demonstrates that S4 mode Lamb wave shows much higher strain sensitivity (-0.48 ppm/Ī¼Ļµ) than Rayleigh wave (0.05 ppm/Ī¼Ļµ) and confirms its advantage of strain sensitivity. Finally, for this one-LWR strain sensor, a method of beat frequency between S4 mode Lamb wave and Rayleigh wave is proposed for temperature compensation and high-sensitivity strain readout

    Hepatic hydrothorax after blunt chest trauma

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    AbstractWe report a successful treatment result in a rare case of hepatitis C virus-related cirrhosis, who had sustained hydrothorax after blunt thoracoabdominal trauma. This was a female patient with liver cirrhosis, Childā€“Turcotteā€“Pugh class A, without ascites before injury. She sustained blunt thoracoabdominal trauma with a left clavicle fracture dislocation and right rib fractures. There was no hemopneumothorax at initial presentation. However, dyspnea and right pleural effusion developed gradually. We inserted a chest tube to relieve the patient's symptoms, and the daily drainage amount remained consistent. Hepatic hydrothorax was confirmed by the intraperitoneal injection of radioisotope 99mTc-sulfur colloid that demonstrated one-way transdiaphragmatic flow of fluid from the peritoneal cavity to pleural cavities. Finally, the hydrothorax was treated successfully by minocycline-induced pleural symphysis. To the best of our knowledge, this is the first case of hepatic hydrothorax developed after thoracoabdominal trauma

    Spleen artery embolization increases the success of nonoperative management following blunt splenic injury

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    AbstractBackgroundSpleen artery embolization (SAE) may increase the success rate of nonoperative management (NOM). The present study investigated the clinical outcome after the installation of SAE in the management of blunt splenic injury.MethodsA retrospective review of hospital records was performed to enroll patients with blunt injury of the spleen. Demographic data and information about the injury severity score, organ injury scale, hospitalization days, management and final outcomes were evaluated. Patients were separated into early and late groups according to the year that SAE was selectively used (2003ā€“2004 and 2005ā€“2008).ResultsSix of eleven (55%) patients in the early group were successfully managed without surgery for blunt splenic injury, whereas all of the 38 patients (100%) in the late group were successfully managed without surgery. Eleven patients (11 of 38; 28.9%) received SAE in the late group. The rate of NOM increased from 55% in the early group to 100% in the late group (pĀ <Ā 0.001). Both early and late groups had similar injury severity score, length of hospitalization, blood transfusion, and complications, and there was no mortality.ConclusionPerformance of SAE for the patients with blunt splenic injury could increase the successful rate of NOM significantly and safely. An algorithm including the angioembolization might be beneficial in the management of patients with blunt spleen trauma

    Microstructural Study of MgB2 in the LiBH4-MgH2 Composite by Using TEM

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    The hampered kinetics of reactive hydride composites (RHCs) in hydrogen storage and release, which limits their use for extensive applications in hydrogen storage S1and energy conversion, can be improved using additives. However, the mechanism of the kinetic restriction and the additive effect on promoting the kinetics have remained unclear. These uncertainties are addressed by utilizing versatile transmission electron microscopy (TEM) on the LiBH4-MgH2 composite under the influence of the 3TiCl3āˆ™AlCl3 additives. The formation of the MgB2 phase, as the rate-limiting step, is emphatically studied. According to the observations, the heterogeneous nucleation of MgB2 relies on different nucleation centers (Mg or TiB2 and AlB2). The varied nucleation and growth of MgB2 are related to the in-plane strain energy density at the interface, resulting from the atomic misfit between MgB2 and its nucleation centers. This leads to distinct MgB2 morphologies (bars and platelets) and different performances in the dehydrogenation kinetics of LiBH4-MgH2. It was found that the formation of numerous MgB2 platelets is regarded as the origin of the kinetic improvement. Therefore, to promote dehydrogenation kinetics in comparable RHC systems for hydrogen storage, it is suggested to select additives delivering a small atomic misfit

    Granzyme G is expressed in the two-cell stage mouse embryo and is required for the maternal-zygotic transition

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    <p>Abstract</p> <p>Background</p> <p>Detailed knowledge of the molecular and cellular mechanisms that direct spatial and temporal gene expression in pre-implantation embryos is critical for understanding the control of the maternal-zygotic transition and cell differentiation in early embryonic development. In this study, twenty-three clones, expressed at different stages of early mouse development, were identified using differential display reverse transcription polymerase chain reaction (DDRT-PCR). One of these clones, which is expressed in 2-cell stage embryos at 48 hr post-hCG injection, shows a perfect sequence homology to the gene encoding the granzyme G protein. The granzyme family members are serine proteases that are present in the secretory granules of cytolytic T lymphocytes. However, the pattern of granzyme G expression and its function in early mouse embryos are entirely unknown.</p> <p>Results</p> <p>Upon the introduction of an antisense morpholino (2 mM) against granzyme G to knock-down endogenous gene function, all embryos were arrested at the 2- to 4-cell stages of egg cleavage, and the <it>de novo </it>synthesis of zygotic RNAs was decreased. The embryonic survival rate was dramatically decreased at the late 2-cell stage when serine protease-specific inhibitors, 0.1 mM 3,4-dichloroisocoumarin (3,4-DCI), and 2 mM phenyl methanesulphonyl fluoride (PMSF), were added to the <it>in vitro </it>embryonic culture medium. Survival was not affected by the addition of 0.5 mM EDTA, a metalloproteinase inhibitor.</p> <p>Conclusion</p> <p>We characterized for the first time the expression and function of <it>granzyme G </it>during early stage embryogenesis. Our data suggest that granzyme G is an important factor in early mouse embryonic development and may play a novel role in the elimination of maternal proteins and the triggering of zygotic gene expression during the maternal-zygotic transition.</p

    Anti-HCV reactive volunteer blood donors distribution character and genotypes switch in Xi'an, China

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    HCV is prevailed in the world as well as in China. Blood transfusion is one of the most common transmission pathways of this pathogen. Although data of HCV infection character were reported during the past years, anti-HCV reactive profile of China donors was not fully clear yet. Furthermore, infection progress was found related to the HCV genotype. Different genotype led to different efficacy when interferon was introduced into HCV therapy. Here we provided character data of HCV infection in China blood donors from the year of 2000 to 2009. The infection rate in local donors was lower than general population and descended from 0.80% to 0.40% or so in recent years. About 83% HCV strains were categorized into genotypes 1b and 2a. But 1b subtype cases climbed and 2a subtype cases decreased. The current study threw more light on HCV infection of blood donors in China, at least in the Northern region
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