SC I E N C E DI L I M A N is published semi-annually (June and December) by the University of the Philippines Diliman through the Office of the Vice Chancellor for Research and Development. The journal features articles of pure and applied sciences. Editorial Board Editor in Chief Jonas P. Quilang, Ph.D. Associate Editors Jose Maria P. Balmaceda, Ph.D. University of the Philippines Louis Angelo M. Danao, Ph.D. University of the Philippines Carlos Primo C. David, Ph.D. University of the Philippines Christian N. Della, Ph.D. University of Glasgow Singapore Arnold M. Guloy, Ph.D. University of Houston Gil S. Jacinto, Ph.D. University of the Philippines Dennis I. Merino, Ph.D. Southeastern Louisiana University Arnel A. Salvador, Ph.D. University of the Philippines Terence P. Tumolva, D.Eng. University of the Philippines Irene M. Villaseñor, Ph.D. University of the Philippines Managing Editor Conchitina R. Cruz, Ph.D. University of the Philippines Editorial Assistant Narita E.C. de las Alas Layout Artist Mirriam M. Velasco Copyeditor Jean Lau Wang On the Cover: The cover image shows the diagram of sensing Uric acid (UA) using a fabricated sensor based on Urate Oxidase (UOx) and Copper (II/I) oxide (CuO/Cu2O) on the surface of a Carbon Paste Electrode (CPE). The UOx-CuO-CPE sensor may be developed into low-cost sensing material for health monitoring applications. Photo from Allan Christopher Yago. Contents of this journal may not be reproduced without the publisher’s written permission except for fair use, i.e. , for personal, educational and research purposes, in accordance with copyright law. Reprinting and republication in any other journal or compilation is likewise prohibited except as provided in the Publication Agreement when the author reprints his/her article for inclusion in any publication where he/she is the author or editor, subject to giving proper credit to the original publication of the article in the journal. The views expressed in the articles are those of the authors and do not necessarily reflect the views of the publisher and the editors. Science Diliman July-December 2020 • Vol. 32 No. 2ISSN Print 0115-7809 ISSN Online 2012-0818 INTERNATIONAL ADVISORY BOARD Teofilo A. Abrajano, Jr., Ph.D. King Abdullah University of Science and Technology Kingdom of Saudi Arabia Rigoberto C. Advincula, Ph.D. Case School of Engineering Case Western Reserve University, USA Kenneth A. Buckle, Ph.D. Professor Emeritus School of Chemical Engineering The University of New South Wales, Australia Jose B. Cruz, Jr., Ph.D. Professor Emeritus University of Illinois, USA University of California, Irvine, USA The Ohio State University, USA John P. Encarnacion, Ph.D. Department of Earth and Atmospheric Sciences Saint Louis University, USA Mihali A. Felipe, Ph.D. Gerstein Lab, Bioinformatics Yale University, USA Robert J. Howell, Ph.D. Department of Mechanical Engineering The University of Sheffield, United Kingdom Jeanmaire E. Molina, Ph.D. Department of Biology Long Island University, Brooklyn, USA Rudolf A. Roemer, Ph.D. Department of Physics University of Warwick, United Kingdom Raul K. Suarez, Ph.D. Professor Emeritus University of California, Sta. Barbara, USA Myra O. Villareal, Ph.D. Life and Environmental Sciences Graduate School University of Tsukuba, Japan