10 research outputs found
On the Bartlett Adjustment for the Partial Likelihood Ratio Test in the Cox Regression Model
The Bartlett adjustment for the partial likelihood ratio test in Cox regression model is established under one-dimensional parameter. If the baseline hazard is unspecified, the adjustment factor can be estimated from the data. The procedure give more accurate probability than the normal approximation to the log-rank test. Abbreviated Title. Bartlett's Adjustment for Partial Likelihood. AMS 1980 subject classification. Primary 62E20, 62G05; Secondary 62P10. Key Words and Phrases. Adjustment, Asymptotic Expansion, Partial likelihood, Cox regression model, Survival data. 1. Introduction and result. In parametric inference, the likelihood ratio test is one of the most popular statistics for inference. One reason for its popularity is the Bartlett (1937) adjustment to the likelihood ratio statistics. When the sample size is small, this adjustment may have a significant improvement over the ordinary asymptotic theory. For a detailed account and the proof, see Barndoff-Nielsen and Cox (1..
Optimal Velocity Control for a Battery Electric Vehicle Driven by Permanent Magnet Synchronous Motors
The permanent magnet synchronous motor (PMSM) has high efficiency and high torque density. Field oriented control (FOC) is usually used in the motor to achieve maximum efficiency control. In the electric vehicle (EV) application, the PMSM efficiency model, combined with the EV and road load system model, is used to study the optimal energy-saving control strategy, which is significant for the economic operation of EVs. With the help of GPS, IMU, and other information technologies, the road conditions can be measured in advance. Based on this information, the optimal velocity of the EV driven by PMSM can be obtained through the analytical algorithm according to the efficiency model of PMSM and the vehicle dynamic model in simple road conditions. In complex road conditions, considering the dynamic characteristics, the economic operating velocity trajectory of the EV can be obtained through the dynamic programming (DP) algorithm. Simulation and experimental results show that the minimum energy consumption and global energy optimization can be achieved when the EV operates in the economic operation area
Technical Report Accompanying
this report. This report is composed of three parts. The first part provides the proof of (3.1) of GFG. The second part derives (3.3) and (3.4) of GFG. The third part formulates and proves an asymptotic convergence theorem for the sequential monitoring of the H-class of statistics proposed in GFG. 1. Proof of the asymptotic representation ( 3.1 ) of GFG Conditions o
Ni electrodes with 3D-ordered surface structures for boosting bubble releasing toward high current density alkaline water splitting
The performance of alkaline water electrolysis (AWE) at high current densities is limited by gas bubble generation on the surface of electrodes, which covers active sites and blocks mass transfer, resulting in lower AWE efficiency. Here, we utilize electro-etching to construct Ni electrodes with hydrophilic and aerophobic surfaces to improve the efficiency of AWE. Ni atoms on the Ni surface can be exfoliated orderly along the crystal planes by electro-etching, forming micro-nano-scale rough surfaces with multiple crystal planes exposed. The 3D-ordered surface structures increase the exposure of active sites and promote the removal of bubbles on the surface of the electrode during the AWE process. In addition, experimental results from high-speed camera reveal that rapidly released bubbles can improve the local circulation of electrolyte. Lastly, the accelerated durability test based on practical working condition demonstrates that the 3D-ordered surface structures are robust and durable during the AWE process
Discovery of 3,3′-Spiro[Azetidine]-2-oxo-indoline Derivatives as Fusion Inhibitors for Treatment of RSV Infection
A new series of 3,3′-spirocyclic-2-oxo-indoline
derivatives was synthesized and evaluated against respiratory syncytial
virus (RSV) in a cell-based assay and animal model. Extensive structure–activity
relationship study led to a lead compound <b>14h</b>, which
exhibited excellent <i>in vitro</i> potency with an EC<sub>50</sub> value of 0.8 nM and demonstrated 71% oral bioavailability
in mice. In a mouse challenge model of RVS infection, <b>14h</b> demonstrated superior efficacy with a 3.9log RSV virus load reduction
in the lung following an oral dose of 50 mg/kg
Edoxaban versus warfarin in patients with atrial fibrillation
Contains fulltext :
125374.pdf (publisher's version ) (Open Access)BACKGROUND: Edoxaban is a direct oral factor Xa inhibitor with proven antithrombotic effects. The long-term efficacy and safety of edoxaban as compared with warfarin in patients with atrial fibrillation is not known. METHODS: We conducted a randomized, double-blind, double-dummy trial comparing two once-daily regimens of edoxaban with warfarin in 21,105 patients with moderate-to-high-risk atrial fibrillation (median follow-up, 2.8 years). The primary efficacy end point was stroke or systemic embolism. Each edoxaban regimen was tested for noninferiority to warfarin during the treatment period. The principal safety end point was major bleeding. RESULTS: The annualized rate of the primary end point during treatment was 1.50% with warfarin (median time in the therapeutic range, 68.4%), as compared with 1.18% with high-dose edoxaban (hazard ratio, 0.79; 97.5% confidence interval [CI], 0.63 to 0.99; P<0.001 for noninferiority) and 1.61% with low-dose edoxaban (hazard ratio, 1.07; 97.5% CI, 0.87 to 1.31; P=0.005 for noninferiority). In the intention-to-treat analysis, there was a trend favoring high-dose edoxaban versus warfarin (hazard ratio, 0.87; 97.5% CI, 0.73 to 1.04; P=0.08) and an unfavorable trend with low-dose edoxaban versus warfarin (hazard ratio, 1.13; 97.5% CI, 0.96 to 1.34; P=0.10). The annualized rate of major bleeding was 3.43% with warfarin versus 2.75% with high-dose edoxaban (hazard ratio, 0.80; 95% CI, 0.71 to 0.91; P<0.001) and 1.61% with low-dose edoxaban (hazard ratio, 0.47; 95% CI, 0.41 to 0.55; P<0.001). The corresponding annualized rates of death from cardiovascular causes were 3.17% versus 2.74% (hazard ratio, 0.86; 95% CI, 0.77 to 0.97; P=0.01), and 2.71% (hazard ratio, 0.85; 95% CI, 0.76 to 0.96; P=0.008), and the corresponding rates of the key secondary end point (a composite of stroke, systemic embolism, or death from cardiovascular causes) were 4.43% versus 3.85% (hazard ratio, 0.87; 95% CI, 0.78 to 0.96; P=0.005), and 4.23% (hazard ratio, 0.95; 95% CI, 0.86 to 1.05; P=0.32). CONCLUSIONS: Both once-daily regimens of edoxaban were noninferior to warfarin with respect to the prevention of stroke or systemic embolism and were associated with significantly lower rates of bleeding and death from cardiovascular causes. (Funded by Daiichi Sankyo Pharma Development; ENGAGE AF-TIMI 48 ClinicalTrials.gov number, NCT00781391.)