Physical Sciences and Mathematics Commons^™

Large Global Variations In Measured Airborne Metal Concentrations Driven By Anthropogenic Sources, Jacob Mcneill, Randal V. Martin, Nofel Lagrosas, 35 Co-Authors

SOSE Affiliate: Manila Observatory

Globally consistent measurements of airborne metal concentrations in fine particulate matter (PM_2.5) are important for understanding potential health impacts, prioritizing air pollution mitigation strategies, and enabling global chemical transport model development. PM_2.5 filter samples (N ~ 800 from 19 locations) collected from a globally distributed surface particulate matter sampling network (SPARTAN) between January 2013 and April 2019 were analyzed for particulate mass and trace metals content. Metal concentrations exhibited pronounced spatial variation, primarily driven by anthropogenic activities. PM_2.5 levels of lead, arsenic, chromium, and zinc were significantly enriched at some locations by factors of 100–3000 compared …

Epithermal Mineralization Of The Bonanza-Sandy Vein System, Masara Gold District, Mindanao, Philippines, Jilian Aira S. Gabo-Ratio, Alfred Elmer Buena, Barbie Ross B. Villaplaza, Betchaida D. Payot, Carla B. Dimalanta, Karlo L. Queaño, Eric A. Andal, Graciano P. Yumul Jr

Environmental Science Faculty Publications

The Masara Gold District in southeastern Mindanao island is an area of prolific hydrothermal copper and gold mineralization. This study documents the mineralization characteristics of the NW-trending Bonanza-Sandy epithermal veins to constrain possible hydrothermal fluid sources and ore-forming mechanisms. Epithermal mineralization in the NW veins is divided into three main stages: Stage 1 - massive quartz-sulfide; Stage 2 - massive to amorphous quartz-carbonate (calcite); and Stage 3 - colloform-cockade quartz-carbonate (bladed rhodochrosite). Stage 1 is the main gold mineralization phase, with chalcopyrite, pyrite, sphalerite and galena occurring with native gold and tellurides. Stages 2 and 3 contain invisible gold in …

Sigma Coloring And Edge Deletions, Agnes Garciano, Reginaldo M. Marcelo, Mari-Jo P. Ruiz, Mark Anthony C. Tolentino

Mathematics Faculty Publications

A vertex coloring c : V(G) → N of a non-trivial graph G is called a sigma coloring if σ(u) is not equal to σ(v) for any pair of adjacent vertices u and v. Here, σ(x) denotes the sum of the colors assigned to vertices adjacent to x. The sigma chromatic number of G, denoted by σ(G), is defined as the fewest number of colors needed to construct a sigma coloring of G. In this paper, we consider the sigma chromatic number of graphs obtained by deleting one or more of its edges. In particular, we study the difference σ(G)−σ(G−e) …

A Climatological Analysis Of The Monsoon Break Following The Summer Monsoon Onset Over Luzon Island, Philippines, Lyndon Mark P. Olaguera, Jun Matsumoto, Hisayuki Kubota, Esperanza O. Cayanan, Flaviana D. Hilario

Physics Faculty Publications

This study investigates the climatology of the monsoon break following the onset of the summer rainy season over Luzon Island (120–122.5°E, 13–22°N) in the Philippines from 1979–2017. The first post-onset monsoon break is remarkable in stations located over the north and central Luzon Island and occurs climatologically in early June. Composite analysis of the large-scale circulation features during the monsoon break period shows that this break is associated with the westward extension of the western North Pacific Subtropical High (WNPSH), which weakened the monsoon southwesterlies and induced enhanced low-level divergence over Luzon Island. The westward extension of the WNPSH may …

Development Of A Mobile Ten Frames App For Philippine K-12 Schools, Debbie Marie Versoza, Ma. Louise Antonette N. De Las Peñas, Jumela F. Sarmiento, Mark Anthony C. Tolentino, Mark L. Loyola

Mathematics Faculty Publications

This paper reports on the Quick Images app, whose design framework is informed by research on ten-structured thinking and gamification principles. Inclusivity was also a major consideration, especially in the context of a developing country. Thus, the app was made freely available and required only moderate system requirements. Pilot studies revealed that the app has the potential to promote children’s ability to see two-digit numbers in relation to tens and ones, which is a major goal of elementary school mathematics. Collaborations with the Philippine Department of Education to ensure the app’s sustained use are also discussed.

Profile Of Volatile Organic Compounds (Vocs) From Cold-Processed And Heat-Treated Virgin Coconut Oil (Vco) Samples, Ian Ken D. Dimzon, Grace B. Tantengco, Noel A. Oquendo, Fabian M. Dayrit

Chemistry Faculty Publications

Virgin coconut oil (VCO) can be prepared with or without heat. Fermentation and centrifuge processes can be done without the use of heat (cold process), while expelling involves heat due to friction. Volatile organic compounds (VOCs) from VCO samples prepared using these three methods were collected using solid phase microextraction (SPME) and analyzed using gas chromatography–mass spectrometry (GC-MS). Twenty-seven VCO samples from nine VCO producers were analyzed. The VOCs from refined, bleached, and deodorized coconut oil (RBDCO) were also obtained for comparison. Fourteen compounds were found to be common in more than 80% of the VCO samples analyzed. These included: …

Weaving Mathematics, Ma. Louise Antonette N. De Las Peñas

Magisterial Lectures

In this lecture, Dr. De las Peñas talks about the intersection of mathematics and Philippine indigenous weaving.

Speaker:

Ma. Louise Antonette N. De Las Peñas is a Professor at the Department of Mathematics and currently the Associate Dean for Research and Creative Work, Loyola Schools, Ateneo De Manila University, Philippines. Her research interests are discrete geometry, mathematical crystallography, group theory, and technology in mathematics education.

She is a recipient of several research awards including the National Research Council of the Philippines (NRCP) Achievement Award in the Mathematical Sciences and the Philippine Commission on Higher Education Republica National Research Award. She …

The Identification Of Heavy Metal Accumulator Ferns In Abandoned Mines In The Philippines With Applications To Mine Rehabilitation And Metal Recovery, Rene Juna R. Claveria, Teresita R. Perez, Ian A. Navarrete, Rubee Ellaine C. Perez, Brian Christian C. Lim

Environmental Science Faculty Publications

This paper focuses on the identification of some plant accumulators of heavy metals that can facilitate mine remediation and rehabilitation in the Philippines and metal recovery or phytomining. Most of these hyperaccumulators are ferns that thrive very well in different terrains and of particular interest are Pityrogramma calomelanos, Pteris vittata, and Pteris melanocaulon that are abundant in abandoned CueAu mining areas. The amounts of Cu and As in the soil and in the aboveground (AG) and belowground (BG) components of the accumulator ferns were determined and the Bioaccumulation Factor (BF) and the Translocation Factor (TF) were derived. Efforts to …

The Limits Of Machine Learning, Ma. Mercedes T. Rodrigo

Magisterial Lectures

In this lecture, Dr. Rodrigo discusses how machine-learned models are constrained by the data on which they are based and by the human beings who control them.

Speaker: Ma Mercedes T Rodrigo is a professor at the Department of Information Systems and Computer Science, the head of the Ateneo Laboratory for the Learning Sciences, and the Executive Director of Arete. Her areas of specialization are educational technology, artificial intelligence in education, and educational data mining.

Bentonite Reinforced Chitosan Scaffold: Effect Of Bentonite Exfoliation On Scaffold Properties, Soma Chakraborty, Cristine Joy M. Pimentel

Chemistry Faculty Publications

Chitosan is under investigation as biodegradable scaffolding material for tissue engineering. Crosslinked chitosan alone cannot form a self-supporting scaffold hence it needs reinforcement. The group reported fabrication of chitosan scaffolds reinforced by exfoliated and non-exfoliated bentonite and compared their properties. Scaffolds were fabricated by freeze-drying technique. Bentonite was exfoliated by allowing it to swell in water for a certain time interval. XRD profile showed that swelling reduced the crystallinity of bentonite. Both types of bentonite dispersed well in the chitosan matrix and imparted structural stability to the scaffolds. Scaffolds had interconnected pores, apparent porosity of scaffold with exfoliated bentonite was …

A Novel Low-Power Synchronous Preamble Data Line Chip Design For Oscillator Control Interface, Shih-Lun Chen, Tsun-Kuang Chi, Min-Chun Tuan, Chiung-An Chen, Liang-Hung Wang, Wei-Yuan Chiang, Ming-Yi Lin, Patricia Angela R. Abu

Department of Information Systems & Computer Science Faculty Publications

In this paper, a novel low-power synchronous preamble data line protocol chip design for serial communication is proposed. The serial communication only uses two wires, chip select (CS) and secure digital (SD), to transmit and receive data between two devices. The proposed protocol aims to use a fewer number of wires for the interface, therefore reducing the complexity as well as the area of the chip design. Moreover, it increases the efficiency through a synchronous serial communication-controlled oscillator. The low-power synchronous preamble data line protocol design was successfully verified using a field-programmable gate array (FPGA) as a master device and …

Low Cost Aip Design In 5g Flexible Antenna Phase Array System Application, Wei-Shin Tung, Wei-Yuan Chiang, Chih-Kai Liu, Chiung-An Chen, Pei-Zong Rao, Patricia Angela R. Abu, Wan-Ming Chen, Faisal Asadi, Shih-Lun Chen

Department of Information Systems & Computer Science Faculty Publications

In this paper, a low cost 28 GHz Antenna-in-Package (AIP) for a 5G communication system is designed and investigated. The antenna is implemented on a low-cost FR4 substrate with a phase shift control integrated circuit, AnokiWave phasor integrated circuit (IC). The unit cell where the array antenna and IC are integrated in the same plate constructs a flexible phase array system. Using the AIP unit cell, the desired antenna array can be created, such as 2 × 8, 8 × 8 or 2 × 64 arrays. The study design proposed in this study is a 2 × 2 unit cell …

Feasibility Of Modifying Existing Chemistry Demonstrations By Using Substitute Materials, Dane Mykel M. Quiambao, Armando M. Guidote Jr, Rhodora F. Nicdao

Chemistry Faculty Publications

This study aimed to reiterate the use of Chemistry demonstrations as effective teaching tools to students while addressing some of its drawbacks, which discourages teachers from doing them such as cost and safety. Four chosen existing Chemistry demonstrations (Blue Bottle Experiment, Copper Sulfate Experiment, Blown Away, Dancing Flames) were modified by using substitute reagents, which are more accessible, relatively safer, and at lower cost. These demonstrations were chosen based on how easily the substitute reagents will be obtained. Afterwards, with the permission of a private junior high school, they were presented to a group of Grade 9 students of their …

Mapping Geographical Inequalities In Access To Drinking Water And Sanitation Facilities In Low-Income And Middle-Income Countries, 2000–17, Aniruddha Deshpande, Robert C. Reiner Jr, Veincent Christian F. Pepito, Arianna Maever L. Amit, Local Burden Of Disease Wash Collaborators, 665 Co-Authors

Ateneo School of Medicine and Public Health Publications

Background

Universal access to safe drinking water and sanitation facilities is an essential human right, recognised in the Sustainable Development Goals as crucial for preventing disease and improving human wellbeing. Comprehensive, high-resolution estimates are important to inform progress towards achieving this goal. We aimed to produce high-resolution geospatial estimates of access to drinking water and sanitation facilities.

Methods

We used a Bayesian geostatistical model and data from 600 sources across more than 88 low-income and middle-income countries (LMICs) to estimate access to drinking water and sanitation facilities on continuous continent-wide surfaces from 2000 to 2017, and aggregated results to policy-relevant …

Pathways Of Hope, Jose Ramon T. Villarin

Magisterial Lectures

In part two of Fr. Jett’s lecture, he discusses the ways in which we can respond to the ecological problems that we face.

Speaker: Fr Jose Ramon T Villarin SJ, is an atmospheric scientist, Jesuit, and outgoing President of the Ateneo De Manila University (2010-2020). Before being elected as University President, he was president of Xavier University-Ateneo De Cagayan. His research and contribution in the field of climate change earned him a seat as the lead reviewer of the UN Convention on Climate Change.

The Pope, The Poor, The Planet, Jose Ramon T. Villarin

Magisterial Lectures

Fr. Jett discusses the complex nature of environmental issues, focusing on climate change as an example, the need to shift to a more integral ecology, and what we need to do as a community and as individuals.

Speaker: Fr Jose Ramon T Villarin SJ, is an atmospheric scientist, Jesuit, and outgoing President of the Ateneo De Manila University (2010-2020). Before being elected as University President, he was president of Xavier University-Ateneo De Cagayan. His research and contribution in the field of climate change earned him a seat as the lead reviewer of the UN Convention on Climate Change.

The Origin Of The Universe: A Vast And Expanding Universe, Bienvenido F. Nebres Sj

Magisterial Lectures

In this video, Fr. Ben delivers a lecture for the course entitled Science, Technology, and Society (STS 10) about the beginnings of our universe: from the big bang, to now.

Speaker: Fr Bienvenido F Nebres, SJ is a Filipino scientist, mathematician, and Jesuit who was the longest-serving university president of the Ateneo de Manila University. He served as University President from 1993-2011. He received the title of National Scientist of The Philippines in 2011 for his contributions in the fields of STEM, education, and development.

The Origin Of The Universe: An Amazing And Mysterious Universe, Bienvenido F. Nebres Sj

Magisterial Lectures

In this video, Fr. Ben delivers a lecture for the course entitled Science, Technology, and Society (STS 10) about blackholes, stardust, and the forces that govern the universe.

Speaker: Fr Bienvenido F. Nebres S.J. is a Filipino scientist, mathematician, and Jesuit who was the longest-serving university president of the Ateneo de Manila University. He served as University President from 1993-2011. He received the title of National Scientist of The Philippines in 2011 for his contributions in the fields of STEM, education, and development.

Teaching College Chemistry In The Time Of Covid-19 Pandemic: A Personal Account Of Teaching In The Old Normal Vs. The New Normal, Armando M. Guidote Jr

Chemistry Faculty Publications

The SARS CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus 2), cause of COVID-19 (CoronaVirus Disease 2019) has afflicted close to 10 million people all over the world resulting to almost half a million deaths. This disease is severely contagious and necessitates social or physical distancing between persons. As such, traditional face-to-face learning is not advised and teachers need to shift to online teaching. There are challenges to online teaching and learning for students, teachers, and the higher education institute, e.g. hardware, bandwidth, and software issues. These will be difficult but these can be overcome eventually. This work is a personal account …

Concerning A Decision-Diagram-Based Solution To The Generalized Directed Rural Postman Problem, Renzo Roel P. Tan, Jun Kawahara, Kazushi Ikeda, Agnes Garciano, Kyle Stephen S. See

Mathematics Faculty Publications

Decision-diagram-based solutions for discrete optimization have been persistently studied. Among these is the use of the zero-suppressed binary decision diagram, a compact graph-based representation for a specified family of sets. Such a diagram may work out combinatorial problems by efficient enumeration. In brief, an extension to the frontierbased search approach for zero-suppressed binary decision diagram construction is proposed. The modification allows for the inclusion of a class-determined constraint in formulation. Variations of the generalized directed rural postman problem, proven to be nondeterministic polynomial-time hard, are solved on some rapid transit systems as illustration. Lastly, results are juxtaposed against standard integer …

Assessing Resilience Against Floods With A System Dynamics Approach: A Comparative Study Of Two Models, Maksims Feofilovs, Francesco Romagnoli, Charlotte Kendra Z. Gotangco, Jairus Carmela C. Josol, Jean Meir Jardeleza, Joseph Emauel Litam, Joaquin Ignacio Campos, Katrina Abenojar

Environmental Science Faculty Publications

Purpose

This paper aims to present the concepts of two different ways of generating a dynamic structure of the urban system to further allow in understanding specific urban behavior facing against flood and further evaluate the potential effect of specific resilience strategies aiming to decrease the exposure and vulnerability of the system.

Design/methodology/approach

Two system dynamics model structures are presented in form of Casual Loop Diagrams.

Findings

The main differences among the tow approaches are the time horizon and the approach that regulates the assessment of the resilience through a dynamic composite indicator: the first model refers to baseline at …

Water-Electricity-Light System: Technology Innovations, Paul M. Cabacungan, Gregory L. Tangonan, Nerissa G. Cabacungan

Environmental Science Faculty Publications

This paper presents the design of the Water-Electricity-Light System (WELS) that is an integration of technologies composed of rain catcher, mechanical filter and UV irradiation, solar panel, charge converter, LED light, inverter and car battery. We traced back its development from a bulky and expensive system that was meant to generate drinking water into a more innovative water cleaning system that integrated lighting and cellphone charging. We tracked the improvements applied to the system to make the design more efficient yet simple enough to be replicated and customized in order to address varied needs. We shared the alterations made to …

Chitosan Curcumin Film As A Sensor For Detection Of O-Nitrophenol And Fluoride Ion Using Fluoresce Quenching Technique, Soma Chakraborty, Andrea Paola D. Ilagan

Chemistry Faculty Publications

Curcumin was immobilized in chitosan films fabricated by solvent casting method. The amount of curcumin immobilization was more when methanol was used as a solvent to dissolve curcumin than the butanol solvent. The maximum amount of curcumin immobilized per gram of chitosan film was 0.023 g. Immobilized curcumin was not released back in water even after prolong contact of the films with water. Fluorescence intensity of the films got quenched when these films were in contact with an aqueous solution of o-nitrophenol (ONP) and sodium fluoride (NaF). The extent of quenching depended on the concentration of these attributes. Fluorescence intensity …

Approximation And Computational Complexity Of Some Hammock Variations Of The Poset Cover Problem, Ivy Ordanel, Proceso L. Fernandez Jr, Richelle Ann B. Juayong, Henry N. Adorna

Department of Information Systems & Computer Science Faculty Publications

The Hammock(⏟𝟐, 𝟐 , … , 𝟐 / 𝒌 )-Poset Cover Problem is a variation of the Poset Cover Problem with the same input – set {𝑳_𝟏, 𝑳_𝟐, … , 𝑳_𝒎} of linear orders over the set {𝟏, 𝟐, … ,𝒏}, but the solution is restricted to a set of simple hammock(𝟐⏟, 𝟐 , … , 𝟐 / 𝒌 ) posets. The problem is NP-Hard when 𝒌 ≥ 𝟑 but is in 𝑷 when 𝒌 = 𝟏. The computational complexity of the problem when 𝒌 = 𝟐 is not yet known. In this paper, …

Underwater Gesture Recognition Using Classical Computer Vision And Deep Learning Techniques, Mygel Andrei M. Martija, Jakov Ivan S. Dumbrique, Prospero C. Naval Jr.

Mathematics Faculty Publications

Underwater Gesture Recognition is a challenging task since conditions which are normally not an issue in gesture recognition on land must be considered. Such issues include low visibility, low contrast, and unequal spectral propagation. In this work, we explore the underwater gesture recognition problem by taking on the recently released Cognitive Autonomous Diving Buddy Underwater Gestures dataset. The contributions of this paper are as follows: (1) Use traditional computer vision techniques along with classical machine learning to perform gesture recognition on the CADDY dataset; (2) Apply deep learning using a convolutional neural network to solve the same problem; (3) Perform …

Phytoremediation Of Heavy Metal Contaminated Wastes From Small-Scale Gold Mining Using Pityrogramma Calomelanos, Zar Che Win, Leslie Joy L. Diaz, Teresita R. Perez, Kiyohiko Nakasaki

Environmental Science Faculty Publications

In this study, viability of employing the waste treatment technique for industrial application was conducted by setting up a phytoremediation protocol for field application where heavy metal (Arsenic and Copper) contaminated adsorbents, i.e. coco peat and nanofiber membrane, used for the treatment of wastewater were also included. An arsenic hyperaccumulator, Pityrogramma calomelanos was used for the treatment of mine wastes-tailings, coco peat and nanofiber membrane. Phytoremediation procedure was established by investigating planting parameters namely ; plot height - (9 cm and 15 cm) and planting distance- (15 cm and 20 cm) for a period of five months. Translocation factor and …

Geometric Realizations Of Abstract Regular Polyhedra With Automorphism Group H3, Mark L. Loyola, Jonn Angel L. Aranas

Mathematics Faculty Publications

A geometric realization of an abstract polyhedron P is a mapping that sends an i-face to an open set of dimension i. This work adapts a method based on Wythoff construction to generate a full rank realization of an abstract regular polyhedron from its automorphism group Gamma. The method entails finding a real orthogonal representation of Gamma of degree 3 and applying its image to suitably chosen (not necessarily connected) open sets in space. To demonstrate the use of the method, it is applied to the abstract polyhedra whose automorphism groups are isomorphic to the non-crystallographic Coxeter group H3.

Geochemistry Of The Late Cretaceous Pandan Formation In Cebu Island, Central Philippines: Sediment Contributions From The Australian Plate Margin During The Mesozoic, Jerali D. Rodrigo, Jilian Aira S. Gabo-Ratio, Karlo L. Queaño, Allan Gil S. Fernando, Leopoldo P. De Silva Jr, Kotaro Yonezu, Yu Zhang

Environmental Science Faculty Publications

The Late Cretaceous Pandan Formation in Cebu Island is one of the oldest sedimentary units in the Central Philippines. The inconsistencies in geological descriptions and interpretation of the depositional environment of the Pandan Formation complicated efforts to determine the origin and tectonic history of the basement of Cebu Island. This study therefore looks into the petrological and geochemical characteristics of the Pandan Formation and their implications for the tectonic development of the Philippine Arc during the late Mesozoic. Petrographic analyses indicate significant contribution from mafic sources with additional inputs from felsic rocks, siliciclastics and metamorphic sources. Enrichment of detrital quartz …

Non-Tropical Cyclone Related Winter Heavy Rainfall Events Over The Philippines: Climatology And Mechanisms, Lyndon Mark Olaguera, Jun Matsumoto, Julie Mae Dado, Gemma T. Narisma

Physics Faculty Publications

This study investigates non-tropical cyclone (TC) related boreal winter heavy rainfall events that lead to extensive flooding (HRF) over the Philippines through a case study and composite analysis. The HRF event examined occurred during January 16–22, 2017 over Cagayan de Oro City (CDO) in Mindanao Island (122–127°E, 5–10°N). The accumulated rainfall over CDO reached by about 180 mm from 00 UTC January 16 to 00 UTC January 17, 2017, exceeding the climatological maximum daily rainfall in January over this area. The interaction of a westward propagating cyclonic circulation over Mindanao Island (MCC) and a shearline that is associated with an …

Design Of A Remote Real-Time Groundwater Level And Water Quality Monitoring System For The Philippine Groundwater Management Plan Project, Carlos M. Oppus, Ma. Aileen Leah G. Guzman, Maria Leonora Guico, Jose Claro N. Monje, Mark Glenn F. Retirado, John Chris T. Kwong, Genevieve C. Ngo, Annael J. Domingo

Electronics, Computer, and Communications Engineering Faculty Publications

Recent technological advances allow us to utilize remote monitoring systems or real-time access of data. While the use of remote monitoring systems is not new, there are still numerous applications that can be explored and improved on, one such is groundwater level and quality monitoring. In the Philippines, the extraction of groundwater for both domestic use and industrial use are manually monitored by the government’s concerned agency and is done at least once per year. With this current setup, the real and significant state of the groundwater is not reflected in a way that is most valuable to the government …