University of the Philippines

About: University of the Philippines is a education organization based out in Quezon City, Philippines. It is known for research contribution in the topics: Population & Health care. The organization has 4589 authors who have published 4437 publications receiving 114846 citations. The organization is also known as: UP.

Estimating risk difference in multicenter studies under baseline-risk heterogeneity.

Abstract: Summary. In this paper, we consider the case of efficient estimation of the risk difference in a multicenter study allowing for baseline heterogeneity. We consider the optimally weighted estimator for the common risk difference and show that this estimator has considerable bias when the true weights (which are inversely proportional to the variances of the center-specific risk difference estimates) are replaced by their sample estimates. In addition, we propose a new estimator for this situation of the Mantel-Haeiiszel type that is unbiased and, in addition, has a smaller variance for small sample sizes within the study centers. Simulations illustrate these findings.

Efficacy and Safety of Subcutaneous Golimumab in Methotrexate-Naive Patients With Rheumatoid Arthritis: Five-Year Results of a Randomized Clinical Trial.

Abstract: Objective: To evaluate the safety and efficacy of golimumab through 5 years in adults with active rheumatoid arthritis (RA) who had not previously received methotrexate (MTX). Methods: In the GO-BEFORE study, 637 MTX-naive adult patients with active RA were randomized (1:1:1:1) to placebo + MTX (group 1), golimumab 100 mg + placebo (group 2), golimumab 50 mg + MTX (group 3), or golimumab 100 mg + MTX (group 4). Inadequate responders in groups 1, 2, and 3 entered early escape at week 28 to golimumab 50 mg + MTX, golimumab 100 mg + MTX, or golimumab 100 mg + MTX, respectively; remaining patients in group 1 could cross over to golimumab 50 mg + MTX at week 52. Assessments included the American College of Rheumatology 20%/50%/70% improvement criteria (ACR20/50/70) response, the Disease Activity Score in 28 joints (DAS28) using C-reactive protein (CRP) level, and the modified Sharp/van der Heijde score (SHS). Efficacy was analyzed using an intent-to-treat (ITT) analysis. Pharmacokinetics and immunogenicity were evaluated at selected visits. Results: A total of 422 patients completed golimumab treatment through week 256. At week 256, 72.8%, 54.6%, and 38.0% of all patients in the full ITT population (n = 637) had an ACR20/50/70 response, respectively; 84.1% had a good or moderate DAS28-CRP response; and 72.7% had a clinically meaningful improvement in physical function. Radiographic progression was minimal in all treatment groups through week 256, and the overall mean change from baseline in SHS was 1.36. Serum trough golimumab concentrations were approximately dose proportional and maintained through week 256. Antibodies to golimumab occurred in 9.6% of patients through week 256. Infections were the most common type of adverse event (AE); 204 of 616 patients (33.1%) had ≥1 serious AE. Conclusions: Clinical efficacy with golimumab treatment was maintained through week 256 of the GO-BEFORE trial of MTX-naive RA patients. No unexpected AEs occurred; safety results through 5 years are consistent with earlier reports.

Leaching of chrysocolla with Ammonia-Ammonium carbonate solutions

Abstract: Chrysocolla was leached in solutions of ammonium hydroxide and ammonium carbonate as a function of the variables: temperature (25 to 55 ‡C), ammonia-ammonium ratio (0.0:1.0 to 1.0:0.0), total ammonia concentration (0.25 to 6.0 M), and particle size (100 to 400 mesh). A model of the leaching behavior was deduced based on: (1) the activation energy of 60.75 kJ/mole (14.51 kcal/mole) for 3 M total NH3 which was dependent on both total ammonia concentration and temperature; (2) first-order dependence of rate on [(NH4)2CO3]; (3) dependence of initial reaction rate on reciprocal of particle diameter; and (4) morphological evidence from SEM and ED AX measurements of diffusion and leaching occurring primarily in surface microcracks and not in the submicroscopic pores. In addition to the importance of diffusion through microcracks in rate control chemical reaction at active surface sites to produce the species, CuNH 3 2 +, is also important. Only a fraction of the Cu atoms react that are exposed to lixiviant. Higher ammonia-ammonium ion concentrations, higher temperatures, or much longer times are required for more refractory Cu atoms to dissolve.

Analysis of competition between wet-seeded rice and barnyardgrass (Echinochloa crus-galli) using a response-surface model

Abstract: Competition between wet-seeded rice and barnyardgrass under two distinct environments was analyzed using a two-parameter response–surface model at the International Rice Research Institute in the Philippines. The findings showed that this model could predict crop yield loss due to weed competition over a wide range of crop and weed densities. The low-tillering, new plant–type cultivar was a weaker competitor and had a higher yield loss than high-tillering cultivar ‘IR72’ and a hybrid. Increasing the crop density could reduce yield loss due to weed competition. This effect was greater for the new plant type than for IR72 and the hybrid when barnyardgrass density was low. In contrast, this effect was less for the new plant type than for IR72 and the hybrid when the weed density was high. Competitiveness of the three rice cultivars was also affected by season. Crop yield loss was higher in the wet season than in the dry season. Nomenclature: Barnyardgrass, Echinochloa crus-galli (L.) Beauv. ECHCG; r...