199 research outputs found

    PREPARATION AND APPLICATION PROPERTIES OF Ti-Si GLYCOL SALT CATALYSTS FOR POLYESTERS

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    Silicon catalysts have very low catalytic activity in polyester (PET). However, titanium catalysts have high catalytic activity in polyester. The simultaneous use of titanium and silicon catalysts is effective in reducing the activity of a single titanium catalytic base agent. In addition, the glycol salts of titanium and silicon (Ti-EG and Si-EG) prepared in the present invention for use in the polyester catalytic process can avoid the introduction of other groups of impurities during the polyester catalytic process, which would lead to premature capping of the polyester in the process of polycondensation and chain building and make it difficult to increase the molecular weight, and thus affect the quality of the polyester. It has been verified that the ratio of Ti:Si is 1:1 (mol), and total amount added to the catalyst is 0.15% of the raw material amount, and the polycondensation temperature was 260-280 °C for 60 min. Compared with the single Ti-EG catalyst, the b* value of the synthesized PET was significantly reduced, and the molecular weight and other indexes did not change too much. In addition, at the end of catalysis, the catalyst was uniformly dispersed in the reaction system, which could be used as a matting agent for PET

    Suppressed Expression of CXCL14 in Hepatocellular Carcinoma Tissues and Its Reduction in the Advanced Stage of Chronic HBV Infection.

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    Introduction(#br)CXCL14 was a significantly under-expressed mRNA in hepatocellular carcinoma tissues according to our microarray analysis, as well as head and neck squamous cell carcinoma and cervical squamous cell carcinoma. CXCL14 was considered a tumor suppressor in some studies; however, its role in HBV infection has not been identified.(#br)Methods(#br)CXCL14 mRNA expression was quantified from 20 male HCC patients, and the fold change in cancer tissues was calculated by comparisons with normal adjacent tissues. Overall, 212 patients with chronic HBV infection and 180 HBV-free controls were recruited to investigate the association between CXCL14 polymorphisms and HBV progression as well as liver function parameters. Serum CXCL14 levels were determined by enzyme-linked immunosorbent assay (ELISA), and comparisons were made between different HBV status and different CXCL14 genotypes.(#br)Results(#br)The mRNA expression of CXCL14 was 0.33-fold in HCC tissues when compared with adjacent tissues. The frequencies of rs2237062 and rs2547, but not rs2237061, were significantly different between patients with mild hepatitis and moderate-to-severe hepatitis. Moreover, rs2237062 and rs2547 polymorphisms correlated with impaired liver function parameters. ELISA results suggested that HBV-free controls had the highest level of CXCL14, while mild hepatitis patients had low levels, and patients with moderate-to-severe hepatitis had the lowest level. GA+AA genotypes of rs2547 were associated with reduced levels of serum CXCL14 because it introduced a stop codon at residue 109.(#br)Conclusion(#br)CXCL14 was significantly suppressed in HBV-related HCC tissues, and its polymorphisms were linked with advanced stage chronic HBV infection and impaired liver function

    High-efficiency single-photon source above the loss-tolerant threshold for efficient linear optical quantum computing

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    Photon loss is the biggest enemy for scalable photonic quantum information processing. This problem can be tackled by using quantum error correction, provided that the overall photon loss is below a threshold of 1/3. However, all reported on-demand and indistinguishable single-photon sources still fall short of this threshold. Here, by using tailor shaped laser pulse excitation on a high-quantum efficiency single quantum dot deterministically coupled to a tunable open microcavity, we demonstrate a high-performance source with a single-photon purity of 0.9795(6), photon indistinguishability of 0.9856(13), and an overall system efficiency of 0.712(18), simultaneously. This source for the first time reaches the efficiency threshold for scalable photonic quantum computing. With this source, we further demonstrate 1.89(14) dB intensity squeezing, and consecutive 40-photon events with 1.67 mHz count rate

    The LAMOST Survey of Background Quasars in the Vicinity of the Andromeda and Triangulum Galaxies -- II. Results from the Commissioning Observations and the Pilot Surveys

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    We present new quasars discovered in the vicinity of the Andromeda and Triangulum galaxies with the LAMOST during the 2010 and 2011 observational seasons. Quasar candidates are selected based on the available SDSS, KPNO 4 m telescope, XSTPS optical, and WISE near infrared photometric data. We present 509 new quasars discovered in a stripe of ~135 sq. deg from M31 to M33 along the Giant Stellar Stream in the 2011 pilot survey datasets, and also 17 new quasars discovered in an area of ~100 sq. deg that covers the central region and the southeastern halo of M31 in the 2010 commissioning datasets. These 526 new quasars have i magnitudes ranging from 15.5 to 20.0, redshifts from 0.1 to 3.2. They represent a significant increase of the number of identified quasars in the vicinity of M31 and M33. There are now 26, 62 and 139 known quasars in this region of the sky with i magnitudes brighter than 17.0, 17.5 and 18.0 respectively, of which 5, 20 and 75 are newly-discovered. These bright quasars provide an invaluable collection with which to probe the kinematics and chemistry of the ISM/IGM in the Local Group of galaxies. A total of 93 quasars are now known with locations within 2.5 deg of M31, of which 73 are newly discovered. Tens of quasars are now known to be located behind the Giant Stellar Stream, and hundreds behind the extended halo and its associated substructures of M31. The much enlarged sample of known quasars in the vicinity of M31 and M33 can potentially be utilized to construct a perfect astrometric reference frame to measure the minute PMs of M31 and M33, along with the PMs of substructures associated with the Local Group of galaxies. Those PMs are some of the most fundamental properties of the Local Group.Comment: 26 pages, 6 figures, AJ accepte

    Specific Correlation between the Hegu Point (LI4) and the Orofacial Part: Evidence from an fMRI Study

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    Acupoint specificity is a foundational concept in acupuncture theory. It is closely related to the function of the acupoint. In this study, we sought to probe the central mechanisms of the specific correlation between LI4 and orofacial part in Bell’s palsy patients. In total, 36 patients with left Bell’s palsy were divided into three groups in random order, and each group received transcutaneous electrical acupoint stimulation (TEAS) at only one of three acupoints (LI4, ST6, and a sham point). A single-block fMRI design paradigm was applied to separately detect neural activity related to different stages of TEAS (prestimulation resting state, stimulation, and poststimulation resting state). Functional magnetic resonance imaging data were acquired during TEAS. There were extensive neuronal activities in the LI4 and ST6 groups and significant differences between stimulation at real and sham points. Brain regions were activated more by real acupoint TEAS than by sham point TEAS. Brain regions that were activated with LI4 and ST6 were broadly overlapping and adjacent. Our results provide supplementary neuroimaging evidence for the existence of acupoint specificity. These results may confirm the central mechanisms of the specific correlation between the Hegu point and the orofacial part

    The validation of the standard Chinese version of the European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire 30 (EORTC QLQ-C30) in pre-operative patients with brain tumor in China

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    <p>Abstract</p> <p>Background</p> <p>Health related quality of life (HRQOL) has increasingly emphasized on cancer patients. The psychometric properties of the standard Chinese version of the European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire 30 (EORTC QLQ-C30, version 3.0) in brain tumor patients wasn't proven, and there was no baseline HRQOL in brain tumor patients prior to surgery.</p> <p>Methods</p> <p>The questionnaire EORTC QLQ-C30 (version 3.0) was administered at three time points: T1, the first or the second day that patients were hospitalized after the brain tumor suspected or diagnosed by MRI or CT; T2, 1 to 2 days after T1, (T1 and T2 were both before surgery); T3, the day before discharge. Clinical variables included disease histologic types, cognitive function, and Karnofsky Performance Status.</p> <p>Results</p> <p>Cronbach's alpha coefficients for multi-item scales were greater than .70 and multitrait scaling analysis showed that most of the item-scale correlation coefficients met the standards of convergent and discriminant validity, except for the cognitive functioning scale. All scales and items exhibited construct validity. Score changes over peri-operation were observed in physical and role functioning scales. Compared with mixed cancer patients assessed after surgery but before adjuvant treatment, brain tumor patients assessed pre-surgery presented better function and fewer symptoms.</p> <p>Conclusions</p> <p>The standard Chinese version of the EORTC QLQ-C30 was overall a valid instrument to assess HRQOL in brain tumor patients in China. The baseline HRQOL in brain tumor patients pre-surgery was better than that in mixed cancer patients post-surgery. Future study should modify cognitive functioning scale and examine test-retest reliability and response validity.</p

    Prevalence and in-hospital outcomes of diabetes among patients with acute coronary syndrome in China: findings from the Improving Care for Cardiovascular Disease in China-Acute Coronary Syndrome Project

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    Abstract Background Guidelines have classified patients with acute coronary syndrome (ACS) and diabetes as a special population, with specific sections presented for the management of these patients considering their extremely high risk. However, in China up-to-date information is lacking regarding the burden of diabetes in patients with ACS and the potential impact of diabetes status on the in-hospital outcomes of these patients. This study aims to provide updated estimation for the burden of diabetes in patients with ACS in China and to evaluate whether diabetes is still associated with excess risks of early mortality and major adverse cardiovascular and cerebrovascular events (MACCE) for ACS patients. Methods The Improving Care for Cardiovascular Disease in China-ACS Project was a collaborative study of the American Heart Association and the Chinese Society of Cardiology. A total of 63,450 inpatients with a definitive diagnosis of ACS were included. Prevalence of diabetes was evaluated in the overall study population and subgroups. Multivariate logistic regression was performed to examine the association between diabetes and in-hospital outcomes, and a propensity-score-matched analysis was further conducted. Results Among these ACS patients, 23,880 (37.6%) had diabetes/possible diabetes. Both STEMI and NSTE-ACS patients had a high prevalence of diabetes/possible diabetes (36.8% versus 39.0%). The prevalence of diabetes/possible diabetes was higher in women (45.0% versus 35.2%, p < 0.001). Even in patients younger than 45 years, 26.9% had diabetes/possible diabetes. While receiving comparable treatments for ACS, diabetes/possible diabetes was associated with a twofold higher risk of all-cause death (adjusted odds ratio 2.04 [95% confidence interval 1.78–2.33]) and a 1.5-fold higher risk of MACCE (adjusted odds ratio 1.54 [95% confidence interval 1.39–1.72]). Conclusions Diabetes was highly prevalent in patients with ACS in China. Considerable excess risks for early mortality and major adverse cardiovascular events were found in these patients. Trial registration NCT02306616. Registered December 3, 201
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