5,715 research outputs found
Comparison of anticoagulation quality between acenocoumarol and warfarin in patients with mechanical prosthetic heart valves. insights from the nationwide plectrum study
Vitamin K antagonists are indicated for the thromboprophylaxis in patients with mechanical prosthetic heart valves (MPHV). However, it is unclear whether some differences between acenocoumarol and warfarin in terms of anticoagulation quality do exist. We included 2111 MPHV patients included in the nationwide PLECTRUM registry. We evaluated anticoagulation quality by the time in therapeutic range (TiTR). Factors associated with acenocoumarol use and with low TiTR were investigated by multivariable logistic regression analysis. Mean age was 56.8 ± 12.3 years; 44.6% of patients were women and 395 patients were on acenocoumarol. A multivariable logistic regression analysis showed that patients on acenocoumarol had more comorbidities (i.e., ≥3, odds ratio (OR) 1.443, 95% confidence interval (CI) 1.081-1.927, p = 0.013). The mean TiTR was lower in the acenocoumarol than in the warfarin group (56.1 ± 19.2% vs. 61.6 ± 19.4%, p < 0.001). A higher prevalence of TiTR (<60%, <65%, or <70%) was found in acenocoumarol users than in warfarin ones (p < 0.001 for all comparisons). Acenocoumarol use was associated with low TiTR regardless of the cutoff used at multivariable analysis. A lower TiTR on acenocoumarol was found in all subgroups of patients analyzed according to sex, hypertension, diabetes, age, valve site, atrial fibrillation, and INR range. In conclusion, anticoagulation quality was consistently lower in MPHV patients on acenocoumarol compared to those on warfarin
Statin liver safety in non-alcoholic fatty liver disease: A systematic review and metanalysis
Aims Statin liver safety in non-alcoholic fatty liver disease (NAFLD) patients is not well defined. We analysed differences in liver function tests, including alanine transaminase aminotransferase (ALT), aspartate transaminase (AST) and gamma-glutamyl transpeptidase (GGT) in NAFLD patients treated or not treated with statins. Methods We performed a systematic review of MEDLINE via PubMed and EMBASE databases and metanalysis of clinical studies investigating levels of ALT, AST and GGT in NAFLD according to statin treatment. Mean difference (MD) and percentage MD were calculated between the two groups. Results We included 22 studies with 2345 NAFLD patients. Overall, 16 were before-after interventional, five were cross-sectional and one was combined cross-sectional/interventional study. In all interventional studies, except one, patients had raised ALT, AST and GGT at baseline. Interventional studies showed reduced ALT values with an MD reduction of -27.2 U/L (95% CI -35.25/-19.15) and a percentage MD reduction of -35.41% (95% CI -44.78/-26.04). Also, AST values were reduced after statin treatment in interventional studies with an MD of -18.82 U/L (95% CI -25.63/-12.02) (percentage -31.78%, 95% CI -41.45/-22.11). Similarly, GGT levels were reduced after statin treatment with an MD of -19.93 U/L (95% CI -27.10/-12.77) (percentage -25.57%, 95% CI -35.18/-15.97). Cross-sectional studies showed no difference in AST and GGT values between patients treated with and without statins. Conclusion In interventional studies, ALT, AST and GGT were reduced after statin treatment with a percentage mean difference of -35.41%, -31.78% and -25.57%, respectively, while observational studies showed a null effect, suggesting liver safety of statins in NAFLD patients
A Study of Marketing Strategy of Sony Electron in China
本文首先对索尼的企业创建、品牌成长、在华历程进行简要回顾。然后运用PEST、波特五力模型、SWOT分析法分析索尼电子在中国市场面临的宏观环境及所处的行业结构,揭示环境和行业结构对索尼电子带来的机会和挑战,分析索尼电子在中国营销的优势、劣势。在此基础上,以4P理论为视角,从产品、价格、渠道、促销四个方面对索尼在华营销策略进行了研究。研究发现,在产品策略方面,索尼注重以消费者需求为导向提供产品,在塑造品牌形象的同时不断加强售后服务网络的建设,以切实的行动维护消费者的利益,赢得了消费者的青睐;在价格策略方面,索尼主要采用了高价位的策略来提升产品定位,采用波浪式的降价来促销中等价位产品,结合中国市场的...The paper first makes a concise review of Sony’s history and its development in China. The paper then analyzes the macro environments and the industrial structure of Sony Electric in China by methods of PEST, Porter’s Five Forces Model and SWOT, to reveal opportunities and threats coming from the environments and the industrial structure, and analyzes Sony’s advantages and disadvantages in China’s...学位:文学硕士院系专业:新闻传播学院广告学系_传播学学号:3062007115249
Atrial fibrillation pattern, left atrial diameter and risk of cardiovascular events and mortality. A prospective multicenter cohort study.
BACKGROUND There are conflicting evidence on the association between atrial fibrillation (AF) pattern, such as persistent/permanent (Pers/Perm) and paroxysmal (PAF) AF and risk of ischemic events. We investigated if left atrial diameter (LAd) may affect the risk of cardiovascular outcomes according to AF pattern. METHODS Prospective multicenter observational including 1,252 non-valvular AF patients (533 PAF and 719 Pers/Perm AF). Study endpoints were cardiovascular events (CVEs), major adverse cardiac events (MACE) and CV death. LA anteroposterior diameter (LAd) was obtained by transthoracic echocardiography. RESULTS Pers/Perm AF patients had a higher proportion of LAd above median than PAF (≥44 mm, 59.5% vs 37.5% respectively, P < .001). In a mean follow-up of 42.2 ± 31.0 months (4,315 patients/year) 179 CVEs (incidence rate [IR] 4.2%/year), 133 MACE (IR 3.1%/year), and 97 CV deaths (IR 2.2%/year) occurred. Compared to patients with LAd below median, those with LAd above the median had a higher rate of CVEs (log-rank test, P < .001), MACE (log-rank test P < .001), and CV death (log-rank test P < .001). Multivariable Cox regression analysis showed that LAd above the median was associated with CVEs, (HR 1.569, 95% CI 1.129-2.180, P = .007) MACE (HR 1.858, 95% CI 1.257-2.745, P = .002) and CV death (HR 2.106, 95% CI 1.308-3.390, P = .002). The association between LAd and outcomes was evident both in PAF and Pers/Perm AF patients. No association between AF pattern and outcomes was found. CONCLUSION LAd is a simple parameter that can be obtained in virtually all AF patients and can provide prognostic information on the risk of CVEs, MACE and CV death regardless of AF pattern
A pulsed nanosecond IR laser diode system to automatically test the Single Event Effects in the laboratory
Abstract A pulsed nanosecond IR laser diode system to automatically test the Single Event Effects in laboratory is described. The results of Single Event Latchup (SEL) test on two VLSI chips (VA_HDR64, 0.8 and 1.2 μm technology) are discussed and compared to those obtained with high-energy heavy ions at GSI (Darmstadt)
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Low‐cost flexible thin‐film detector for medical dosimetry applications
The purpose of this study is to characterize dosimetric properties of thin film photovoltaic sensors as a platform for development of prototype dose verification equipment in radiotherapy. Towards this goal, flexible thin‐film sensors of dose with embedded data acquisition electronics and wireless data transmission are prototyped and tested in kV and MV photon beams. Fundamental dosimetric properties are determined in view of a specific application to dose verification in multiple planes or curved surfaces inside a phantom. Uniqueness of the new thin‐film sensors consists in their mechanical properties, low‐power operation, and low‐cost. They are thinner and more flexible than dosimetric films. In principle, each thin‐film sensor can be fabricated in any size (mm2 – cm2 areas) and shape. Individual sensors can be put together in an array of sensors spreading over large areas and yet being light. Photovoltaic mode of charge collection (of electrons and holes) does not require external electric field applied to the sensor, and this implies simplicity of data acquisition electronics and low power operation. The prototype device use for testing consists of several thin film dose sensors, each of about 1.5 cm×5 cm area, connected to simple readout electronics. Sensitivity of the sensors is determined per unit area and compared to EPID sensitivity, as well as other standard photodiodes. Each sensor independently measures dose and is based on commercially available flexible thin‐film aSi photodiodes. Readout electronics consists of an ultra low‐power microcontroller, radio frequency transmitter, and a low‐noise amplification circuit implemented on a flexible printed circuit board. Detector output is digitized and transmitted wirelessly to an external host computer where it is integrated and processed. A megavoltage medical linear accelerator (Varian Tx) equipped with kilovoltage online imaging system and a Cobalt source are use to irradiate different thin‐film detector sensors in a Solid Water phantom under various irradiation conditions. Different factors are considered in characterization of the device attributes: energies (80 kVp, 130 kVp, 6 MV, 15 MV), dose rates (different ms × mA, 100–600 MU/min), total doses (0.1 cGy‐500 cGy), depths (0.5 cm–20 cm), irradiation angles with respect to the detector surface (0°‐180°), and IMRT tests (closed MLC, sweeping gap). The detector response to MV radiation is both linear with total dose (~1‐400 cGy) and independent of dose rate (100‐600 Mu/min). The sensitivity per unit area of thin‐film sensors is lower than for aSi flat‐panel detectors, but sufficient to acquire stable and accurate signals during irradiations. The proposed thin‐film photodiode system has properties which make it promising for clinical dosimetry. Due to the mechanical flexibility of each sensor and readout electronics, low‐cost, and wireless data acquisition, it could be considered for quality assurance (e.g., IMRT, mechanical linac QA), as well as real‐time dose monitoring in challenging setup configurations, including large area and 3D detection (multiple planes or curved surfaces). PACS number: 87.56.F
Data acquisition system for a proton imaging apparatus
New developments in the proton-therapy field for cancer treatments, leaded Italian physics researchers to realize a proton imaging apparatus consisting of a silicon microstrip tracker to reconstruct the proton trajectories and a calorimeter to measure their residual energy. For clinical requirements, the detectors used and the data acquisition system should be able to sustain about 1 MHz proton rate. The tracker read-out, using an ASICs developed by the collaboration, acquires the signals detector and sends data in parallel to an FPGA. The YAG:Ce calorimeter generates also the global trigger. The data acquisition system and the results obtained in the calibration phase are presented and discussed
Protons in near earth orbit
The proton spectrum in the kinetic energy range 0.1 to 200 GeV was measured
by the Alpha Magnetic Spectrometer (AMS) during space shuttle flight STS-91 at
an altitude of 380 km. Above the geomagnetic cutoff the observed spectrum is
parameterized by a power law. Below the geomagnetic cutoff a substantial second
spectrum was observed concentrated at equatorial latitudes with a flux ~ 70
m^-2 sec^-1 sr^-1. Most of these second spectrum protons follow a complicated
trajectory and originate from a restricted geographic region.Comment: 19 pages, Latex, 7 .eps figure
Isotopic Composition of Light Nuclei in Cosmic Rays: Results from AMS-01
The variety of isotopes in cosmic rays allows us to study different aspects
of the processes that cosmic rays undergo between the time they are produced
and the time of their arrival in the heliosphere. In this paper we present
measurements of the isotopic ratios 2H/4He, 3He/4He, 6Li/7Li, 7Be/(9Be+10Be)
and 10B/11B in the range 0.2-1.4 GeV of kinetic energy per nucleon. The
measurements are based on the data collected by the Alpha Magnetic
Spectrometer, AMS-01, during the STS-91 flight in 1998 June.Comment: To appear in ApJ. 12 pages, 11 figures, 6 table
Search for antihelium in cosmic rays
The Alpha Magnetic Spectrometer (AMS) was flown on the space shuttle
Discovery during flight STS-91 in a 51.7 degree orbit at altitudes between 320
and 390 km. A total of 2.86 * 10^6 helium nuclei were observed in the rigidity
range 1 to 140 GV. No antihelium nuclei were detected at any rigidity. An upper
limit on the flux ratio of antihelium to helium of < 1.1 * 10^-6 is obtained.Comment: 18 pages, Latex, 9 .eps figure
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