Mean Response Models of Repeated Measurements in Presence of Varying Effectiveness Onset

Repeated measurements are often collected over time to evaluate treatment efficacy in clinical trials. Most of the statistical models of the repeated measurements have been focusing on their mean response as function of time. These models usually assume that the treatment has persistent effect of constant additivity or multiplicity on the mean response functions throughout the observation period of time. In reality, however, such assumption may be confounded by the potential existence of the so-called effectiveness action onset, although they are often unobserved or difficult to obtain. Instead of including nonparametric time-varying coefficients in the mean response models, we propose and study some semiparametric mean response models to accommodate such effectiveness times. Our methodologies will be demonstrated by a real randomised clinical trial data

Semiparametric Regression Analysis of Mean Residual Life with Censored Survival Data

As a function of time t, mean residual life is the remaining life expectancy of a subject given survival up to t. The proportional mean residual life model, proposed by Oakes & Dasu (1990), provides an alternative to the Cox proportional hazards model to study the association between survival times and covariates. In the presence of censoring, we develop semiparametric inference procedures for the regression coefficients of the Oakes-Dasu model using martingale theory for counting processes. We also present simulation studies and an application to the Veterans\u27 Administration lung cancer data

Supersolidity from defect-condensation in the extended boson Hubbard model

We study the ground state phase diagram of the hard-core extended boson Hubbard model on the square lattice with both nearest- (nn) and next-nearest-neighbor (nnn) hopping and repulsion, using Gutzwiller mean field theory and quantum Monte Carlo simulations. We observe the formation of supersolid states with checkerboard, striped, and quarter-filled crystal structures, when the system is doped away from commensurate fillings. In the striped supersolid phase, a strong anisotropy in the superfluid density is obtained from the simulations; however, the transverse component remains finite, indicating a true two-dimensional superflow. We find that upon doping, the striped supersolid transitions directly into the supersolid with quarter-filled crystal structure, via a first-order stripe melting transition.Comment: Revtex 4, 6 pages, 9 figure

Investigation of intrinsic channel characteristics of hydrogenated amorphous silicon thin-film transistors by gated-four-probe structure

We use a new hydrogenated amorphous silicon (a-Si:Ha-Si:H) device structure, the gated-four-probe a-Si:Ha-Si:H thin-film transistor (TFT), to investigate the intrinsic channel characteristics of inverted-staggered a-Si:Ha-Si:H TFTs without the influence of source/drain series resistances. The experimental results have shown that, for the conventional a-Si:Ha-Si:H TFT structure, the field-effect mobility, threshold voltage, and field-effect channel conductance activation energy have a strong dependence on a-Si:Ha-Si:H thickness and TFT channel length. On the other hand, for the gated-four-probe a-Si:Ha-Si:H TFT structure, these values are a-Si:Ha-Si:H thickness and TFT channel length independent, clearly indicating that this new a-Si:Ha-Si:H TFT structure can be effectively used to measure the channel intrinsic properties of a-Si:Ha-Si:H TFTs. © 1998 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70688/2/APPLAB-72-22-2874-1.pd

Assessing the safety and efficacy of switching to brinzolamide/timolol fixed combination as a replacement therapy in patients with uncontrolled intraocular pressure in Taiwan

AbstractPurposeThe objective of this study is to assess the safety and efficacy of switching to brinzolamide 1% and timolol 0.5% fixed combination (BTFC) from prior pharmacotherapy in patients with open-angle glaucoma (OAG) or ocular hypertension (OH) in Taiwan.MethodsThis was a multicenter, open-labeled, interventional prospective study. The 8-week study involved patients with OAG or OH with uncontrolled intraocular pressure (IOP) and consisted of three study visits to the clinical site. Patients were instructed to discontinue their prior medications at the first visit, prior to starting the study medication. Enrolled patients were dosed with BTFC twice daily in both eyes for 8 weeks. IOP measurements and safety evaluations were conducted at both Week 4 and Week 8.ResultsA total of 74 patients were enrolled. The overall mean IOP reductions from baseline after Week 8 of BTFC was 3.45 mmHg (15.42%); when subgrouped by prior medication class (β-blockers vs. non-β-blockers), the reduction in mean IOP after transitioning to BTFC at Week 8 was as follows: subgroup β-blockers were 3.23 mmHg (14.9 %) and non-β-blockers were 3.58 mmHg (15.25%). All mean IOP changes from baseline were statistically significant (p < 0.001). Of the 69 patients (per protocol population) who were switched to BTFC regardless of prior therapy, 37 (53.6%) patients at Week 4 and 38 (55.1%) patients at Week 8 had IOP ≤ 18 mmHg. No treatment-related serious adverse events were reported in this study.ConclusionThe results of this study demonstrated the potential benefit of using BTFC as a replacement therapy in order to ensure adequate IOP control. BTFC administered twice daily was safe and effective in patients with uncontrolled IOP in Taiwan