Allan Abraham B. Padama
Institute of Mathematical Sciences and Physics
College of Arts and Sciences
UP Diliman
Dilute Concentrations of Sb (Bi) Dopants in Sn-site Enhance the Thermoelectric Properties of TiNiSn Half-Heusler Alloys: A First-principles Study, Japanese Journal of Applied Physics, 59(3): 035003, 2020
Enthalpy and defect formation energies of Sb- and Bi- modified TiNiSn alloys.
Figure-of-merit of Sb- and Bi- modified TiNiSn alloys.
In this work, we studied the properties of thermoelectric materials based on Titanium-Nickel-Tin (TiNiSn) alloys. Thermoelectric materials are used to convert thermal energy to electric energy. They are used to harvest waste heat for energy efficiency and for cooling related applications. By performing computational investigations based on density functional theory, we showed that it is possible to enhance the thermoelectric property of the material by incorporating low concentration of Bismuth (Bi) or Antimony (Sb). These alloying species will replace some of the Sn atoms in the TiNiSn. The improved property of the modified TiNiSn is due to factors such as increased mobility and the increased number of electrons in the system. We also showed that the formation of the modified material is energetically favored and thus, it is possible that such material could be synthesized experimentally. This study gives option and motivation to experimentalists in realizing efficient and stable thermoelectric materials.
Significance:
Thermoelectric materials can directly convert thermal energy to electric energy. Given this ability, they are usually employed in devices to harvest waste heat for energy efficiency and for cooling related applications. Titanium-Nickel-Tin (TiNiSn) based alloys are popular materials for thermoelectric applications due to their stability and good efficiency. Interestingly, it is found that modifying the material by alloying it with other elements would further improve its stability and performance. Our study focused on the (atomic-scale) design of modified TiNiSn. Our results provide insights on the type and concentration of alloying element that will improve the thermoelectric property of TiNiSn. Researchers could likewise utilize the methods employed in our work to measure the stability and the thermoelectric properties of other materials. Lastly, this study gives option and motivation to experimentalists in realizing efficient and stable thermoelectric materials.
Link to the article: https://doi.org/10.35848/1347-4065/ab74c8
Impact factor: (2018/2019) (2018/2019) 1.471
Ferdinand G. Manegdeg1 , Leif Oliver B. Coronado1 and Ronard G.Paña1
1Department of Mechanical Engineering, College of Engineering (UP Diliman)
Medical Waste Treatment and Electricity Generation Using Pyrolyzer-Rankine Cycle for Specialty Hospitals in Quezon City, Philippines,
IOP Conference Series: Earth and Environmental Science, 463: 012180, doi://10.1088/1755-1315/463/1/012180, 2020
The research was about the application of a pyrolyzer, a thermochemical equipment that decomposes input products like wastes using heat which operates at a vacuum condition, for treatment of medical waste. Since medical waste is hazardous and dangerous to health for it may still contain viruses and microorganisms that can harm individuals, treatment like autoclaving is applied. The problem is this type of treatment is energy intensive that is why an alternative is being proposed in this study. Also, one benefit of using pyrolyzer is that it generates synthetic gas which can be used as a fuel for power generation. Waste generation from four specialty hospitals in Quezon city was surveyed, namely Lung Center of the Philippines, National Kidney and Transplant Institute, Philippine Heart Center, and Philippine’s Children Medical Center. It includes data gathering, characterization and weighing of the actual wastes from these institutions. The collected data would determine the type of waste produced, amount in weight, and daily rate of waste generation which is essential to calculate the calorific value and the design of the pyrolyzer. Numerical simulations were applied using the equation of and economic value of the proposed technology was assessed.
Significance:
The research which focused on the study of using Pyrolyzer to the treatment of medical wastes with the additional benefit of generating energy for specialty hospitals in Quezon city, Philippines could be a revolutionary research. Since, it employs a better alternative in terms of energy and economic impact. Medical waste is considered to be hazardous and toxic that is why it is forbidden by law to dispose of it without any treatment. In the Philippines, autoclaving is the most used treatment process for hazardous waste. This kind of treatment utilized high energy for its process which is not sustainable for all of the hospitals while the treatment of applying pyrolyzer could be a state-of-the-art technology since it would not only treat the waste but also produce energy for the beneficiary of the hospital or any organization in the grid.
Link to the article: https://iopscience.iop.org/article/10.1088/1755-1315/463/1/012180
Impact factor: Not applicable
Maria Ines Rosana D. Balangue-Tarriela
National Institute of Geological Sciences
College of Science
UP Diliman
Geology, Alteration, and Mineralization of the Kay Tanda Epithermal Gold Deposit, Lobo, Batangas, Philippines, Resource Geology, 69 (4): 351-384, 2019
The Philippine Archipelago is dotted with numerous ore deposits of different types, including but not limited to laterite deposits, massive sulphides, porphyry copper deposits and epithermal Au deposits. The Kay Tanda mineral deposit in Batangas province is one of the least studied Philippine epithermal deposits. Epithermal deposits are formed by hot circulating solutions with temperatures not more than 300degC (hydrothermal fluids) depositing metals ( gold, silver and other metals) at shallow levels (up to 2 km deep).
This paper presents results of field mapping, core logging and laboratory analyses (petrographic and mineragraphic analyses, X-ray diffraction, scanning electron microscope (SEM) and electronmicroprobe analysis (EPMA) that describes the Kay Tanda deposit in terms of the geology, mineralization style and paragenesis, age (K-Ar) and mineralization controls (fluid inclusions and mineralogy).
The Kay Tanda deposit is characterized by an intrusive heat source and associated volcanic rocks. Mineralization determined by K-Ar dating, was dated around 5.9 ± 0.2 to 5.5 ± 0.2 Ma. The fluid responsible for the formation of the deposit evolved from acidic to near neutral pH and temperatures from 220deg to 290deg C with boiling as the main process that led to the deposition. Paragenetic studies, fluid inclusion studies, quantitative gas analysis and hydrothermal mineralogy indicated at least six stages of hydrothermal and ore mineralization resulting to the deposition of Au and base metal (Pb, Cu, Zn).
It is believed that mixed species planting benefits conservation, increase carbon stock potentials, reduce negative effects on soil of fast-growing trees, and provide natural habitats for local fauna.
Significance:
The research presents geological, hydrothermal alteration, and mineralization characteristics (assemblage, stages, style, age, paragenetic sequence of ore deposition), as well as the hydrothermal fluid properties of one of the least, studied epithermal gold deposit in Batangas, the Kay Tanda deposit. The information from this research will be valuable in establishing metallogenic history of Batangas and can contribute to the search and understanding of epithermal deposits in the Philippines and other areas.
Link to the article: https://onlinelibrary.wiley.com/doi/abs/10.1111/rge.12205
Impact factor: (2018/2019) 1.109
Emmanuel S. Baja1 and Paul Marl B. Medina2
1Institute of Clinical Epidemiology, National Institutes of Health (UP Manila)
2Department of Biochemistry and Molecular Biology, College of Medicine (UP Manila)
Development of a Mobile Game to Influence Behavior Determinants of HIV Service Uptake Among Key Populations in the Philippines: User-Centered Design Process,
JMIR Serious Games, 7(4): e13695, doi: 10.2196/13695, 2019
To curb the HIV epidemic around the world, a new game application has been developed to raise awareness about the deadly disease. Dubbed as Battle in the Blood (#BitB), the app is a unique puzzle and turn-based combat mobile game designed to influence social norms, knowledge and attitudes towards HIV/AIDs. It aims to challenge the belief that infected individuals can no longer live a long and fulfilling life. #BitB is a “digital advocacy gaming application” that has been developed to help address the barriers to HIV testing and counseling. The problem here in the Philippines is the stigma and the lack of information on HIV, especially among the MSMs (males having sex with males) and TGW (transgender women). They are afraid to undergo testing. They don’t want to go to clinics because they are afraid of the possible results, #BitB game is the first gaming app that would hopefully help increase the uptake of HIV testing and treatment in the Philippines. It very powerful communication tool to address the stigma of HIV especially among young MSMs and transgender women who are at a higher risk for HIV infection. This project wants the public to know that there are medications for HIV. It is a chronic disease like diabetes. A HIV positive individual can still live a normal productive life if one adheres to his/her medication and observes a healthy lifestyle.
Significance:
The Philippines has the fastest growing HIV epidemic in the Southeast Asia region. The dominant mode of transmission reported in the Philippines is sexual contact among males who have sex with males (MSM) and transgender women (TGW). Mobile games contain structural elements that effectively engage users and it is through these elements that mobile games could influence behavior determinants. Players can model health-related behavior and witness positive and negative outcomes within a safe environment. This study aimed to develop a playable and acceptable game for health, targeted at young key populations in the Philippines. The resulting product is a game that is accessible, simple, and entertaining because of universally recognized game mechanics, small file size, and offline gameplay. The game called Battle in the Blood (BitB) is a serious mobile game application that could help change the behavior of vulnerable age groups towards HIV-related risks.
Link to the article: https://games.jmir.org/2019/4/e13695/
Impact factor: (2018/2019) 3.351
Derick Erl B. Sumalapao1 and Nelson R. Villarante2
1Department of Epidemiology and Biostatistics, College of Public Health (UP Manila)
2Department of Physical Sciences and Mathematics, College of Arts and Sciences (UP Manila)
In vitro Resistance Pattern of Selected Antifungal Azoles against Candida albicans Biofilms on Silicone Nasogastric Tube,
Journal of Pure and Applied Microbiology, 13(4): 1881-1891, 2019
Fig. 1. Fluorescence microscopy of Candida albicans biofilms (in white arrows) on the surface of silicone nasogastric tube at (A) 24 h, (B) 48 h, and (C) 72 h. Magnification: X40
Fig. 2. Susceptibility profile of (A) 24-h, (B) 48-h, and (C) 72-h Candida albicans biofilm: fluconazole (FCA), miconazole (MCL), posaconazole (POS), and voriconazole (VO)
Prolonged use of implanted medical devices has been linked with device-associated infections. Since enteral tube feeding is increasing worldwide, the present study described the morphology of Candida albicans biofilms on the surface of silicone nasogastric tube using fluorescence microscopy. With the emergence of multidrug-resistant fungal infections, the present study assessed the susceptibility profile of the biofilms to antifungal azoles namely fluconazole, miconazole, voriconazole, and posaconazole using the standard disc diffusion method. Microscopic studies of C. albicans biofilms revealed a complex heterogeneous structure with yeast cells and hyphal elements entrenched within a polysaccharide matrix. Planktonic C. albicans cells remained susceptible with posaconazole, fluconazole, miconazole, and voriconazole. However, the fungal biofilms exhibited resistance with miconazole.
Significance:
Findings of the present study can possibly provide information regarding the resistance of fungal biofilms with antifungal azoles. Demonstration of common biofilm features will extend the findings of this study beyond fungi to polymicrobial infections, as new information and insights will influence several disciplines ranging from environmental microbiology to pharmaceutical drug design intended for biofilm-associated infections.
Link to the article: https://doi.org/10.22207/JPAM.13.4.01
Impact factor: Not applicable
Derick Erl B. Sumalapao1 and Nelson R. Villarante2
1Department of Epidemiology and Biostatistics, College of Public Health (UP Manila)
2Department of Physical Sciences and Mathematics, College of Arts and Sciences (UP Manila)
A Second-order Kinetic Model on the Survival Profile of Candida albicans in biofilms,
Current Research in Environmental & Applied Mycology 9(1): 187-193, 2019
Fig. 1 – Micrographs of Candida albicans biofilms on (A) polyvinyl chloride endotracheal tube, (B) silicone urinary catheter, and (C) silicone nasogastric tube surfaces. Structures in yellow arrows indicate 24-h biofilm formation viewed using light microscopy at high power objective.
Fig. 2 – Morphological appearance of Candida albicans colonies in Sabouraud dextrose agar plates, 24 h incubation at 37°C
The prevalent use of indwelling medical devices has almost paralleled the increasing frequency of fungal infections commonly found in clinical practice. The present study examined Candida albicans biofilms on the surfaces of polyvinyl chloride endotracheal tube, silicone urinary catheter, and silicone nasogastric tube. The viable C. albicans in biofilms were quantified using standard plating procedure. Several kinetic rate equations were employed to describe the survival profile of the viable population. Candida albicans exhibited remarkably heterogeneous growth patterns on the different medical devices reflecting variations on its adhesion potential and biofilm formation. A significant difference in the viability of C. albicans in biofilms on the surfaces of the medical devices was observed among monitoring points. Survival profile of C. albicans in biofilms followed a second-order kinetic model.
Significance:
Quantitative descriptions regarding growth patterns and kinetic profile of Candida albicans were obtained on these model biofilms. These findings can provide additional information to better understand the complex biology of C. albicans and to possibly explain the resistance patterns of fungal biofilms with the existing available antifungal drugs.
Link to the article: http://www.creamjournal.org/pdf/CREAM_9_1_16.pdf
Impact factor: Not applicable
Tomas D. Reyes Jr.
Institute of Renewable Natural Resources
College of Forestry and Natural Resources
UP Los Baños
Diversity and Carbon Stock Assessment of an Indigenous Philippine Tree Farm, IOP Conference Series: Earth and Environmental Science, 449: 012033, 2020
Native trees at the farm
Façade of the University Indigenous Tree Farm
This research was conducted in the Bohol Island State University (BISU) Indigenous Tree Farm. It is a one-hectare tree farm planted to more than one thousand native trees collected in all parts of Bohol province. It serves as a showcase farm, not only of the university but also of the Department of Environment and Natural Resources (DENR) – Bohol. It becomes part of the environment/nature tourism circuit of the province and now considered sources of seeds for nearby communities and interested individuals.
The study intends to present the farm’s baseline data on species richness and diversity including its contribution to the regional carbon stocks. Species richness, in this study, means the number of species in the whole tree farm. There were about 44 species with a mean number of individuals of about 29. This totaled to 1,342 individuals of varying morpho-measurements such as diameter (cm) and height (m). Species diversity was computed to be 2.9 and this value according to Fernando et al. (1998) means moderate diversity. Diversity is the combined estimates of species richness and individual species counts. Large number of species and more even distribution of individuals in each species, means high species diversity. Diversity values range from <1 to >5. Recruitment of new species from seeds brought by hoarding animals was found evident and may increase the diversity in the next five to 10 years.
The computed overall tree carbon stock of a six-year old tree farm was about 9.205 tons. This is quite small compared to a one-generation-old (50-75 years) forest stand with carbon stocks ranging from 200 to 350 tons of carbon per hectare. Determining the tree farm’s current carbon stock, and perhaps monitoring its regular growth, would somehow provide baseline information on how large or small tree farms and plantations store biomass and sequester carbon from the atmosphere. Sequestration rate may also be computed from these repeated measurements.
It is believed that mixed species planting benefits conservation, increase carbon stock potentials, reduce negative effects on soil of fast-growing trees, and provide natural habitats for local fauna.
Significance:
This research is an additional contribution to studies related to diversity assessment and carbon stock estimation in indigenous tree farms in the country. It is imperative that baseline information on diversity and carbon stocks be determined especially if regular monitoring and assessment are to be conducted. The farm started to gain new species recruits brought by birds, bats and hoarding rodents. The BISU Indigenous Tree Farm is one of the successful DENR-certified tree farms in Bohol established in 2014.
Link to the article: https://iopscience.iop.org/article/10.1088/1755-1315/449/1/012033
Impact factor: Not applicable
John Aries I. Malahito1 and Maria Ana T. Quimbo1
1Institute for Governance and Rural Development, College of Public Affairs and Development (UP Los Baños)
Creating G-Class: A Gamified Learning Environment for Freshman Students,
E-learning and Digital Media. 17(2):, 94-110, 2020
In this era of digital media, teachers are competing against technological advancements in gaining students’ engagement and attention. Incorporating game elements in the learning environment known as gamification is a new field of study that re-engages students in learning. This study was done primarily to create a gamified learning environment that will serve as another teaching strategy to engage students in learning. The learning environment was aligned with the principles of gamification and was called Gamified-Class or simply G-Class. Using data gathered from 27 freshman college students, G-Class was developed following the Analysis–Design–Development–Implementation–Evaluation model of instructional design and using the Mechanics–Dynamics–Aesthetics framework of game design. The material was implemented in a General Physics class through a quasi experimental research design. A G-Class mobile and desktop application together with a user guide was created. G-Class was evaluated both as instructional design material and as instructional task. As an instructional design, it was assessed in terms of content and learning objectives; design, interactivity, and usability; and assessment aligned with learning outcomes. As an instructional task, G-Class was assessed using the Intrinsic Motivation Inventory which consisted of four subscales in a 7-point Likert scale, namely, interest/enjoyment, perceived competence, choice, and pressure/tension. Overall, G-Class was given a positive rating both as instructional material and as an instructional task. With an overall rating of 5.60, students were found to be more engaged with their subject. Applying gamification in the learning environment pointed to its beneficial effects in enhancing students’ engagement in learning.
Significance:
This study designed a hybrid framework to create a gamified learning environment. This is based on the premise that technological advancements are becoming more and more accessible to the learners and a common notion is to utilize those advancements in the learning environment. A learning environment where gamification can be applied is on an e-learning environment. An e-learning environment has the advantage of developing students’ desired learning content and gives them a new and innovative way to learn through utilizing digital and electronic media (Lin et al., 2014). Since gamification is a recent research development and is still in progress, there is still a limited sample of empirical studies in gamifying a learning environment. Recent researches are varied when it comes to the effects of gamification elements mainly due to lack of comparison groups, short treatments, singular assessments, and a lack of validated measures (Hanus and Fox, 2015; Lieberoth, 2014). Thus, this study intends to contribute to the literature concerning the development of a gamified learning environment. This will also help instructional designers in making learning materials that are aligned with the concepts of gamification. It is believed that gamifying the learning environment will help students be more engaged and motivated to learn in an enjoyable and entertaining way. This may indirectly, if not directly, result to an increased performance of the students in terms of their academic standing.
Link to the article: https://journals.sagepub.com/doi/10.1177/2042753019899805
Impact factor: Not applicable
Derick Erl B. Sumalapao1 and Nelson R. Villarante2
1Department of Epidemiology and Biostatistics, College of Public Health (UP Manila)
2Department of Physical Sciences and Mathematics, College of Arts and Sciences (UP Manila)
Polymeric Compositions of Medical Devices Account for the Variations in Candida albicans Biofilm Structural Morphology,
Current Research in Environmental & Applied Mycology 10(1): 1–9, 2020
Fig. 1 – Scanning electron micrographs of Candida albicans biofilms on the surfaces of polyvinyl chloride endotracheal tube (A, B), silicone urinary catheter(C, D), and silicone nasogastric tube (E, F) at 72 h. Magnification: X2000 (A, C, E), X5000 (B, D, F).
Fig. 2 – Infrared spectroscopic profile of (A) polyvinyl chloride endotracheal tube, (B) silicone urinary catheter, and (C) silicone nasogastric tube.
The increase in the number of fungal infections has been associated with the prevalent use of medical devices. This study assessed the morphological structure of Candida albicans biofilms on the surfaces of medical devices using scanning electron microscopy and characterized the polymeric compositions of these medical devices using infrared spectroscopic study. Biofilms on the surfaces of these medical devices exhibited variations in morphological topographies ranging from the presence of ellipsoid and spherical yeast cells joining end to end, to the growth of pseudohyphae and hyphae formation with chains of cylindrical cells, and the formation of several microcolonies entrenched in a polymeric matrix. The differences in the spectroscopic profiles of the medical devices accounted for the variations in the structural morphology of these biofilms.
Significance:
Given the information on the variations in the morphological appearance of the biofilms on medical device surfaces, these differences on the polymeric compositions of the medical devices can provide explanations on the adhesion potential, biofilm formation, structural morphology, and subsequent susceptibility pattern of the sessile organism to antifungal drugs.
Link to the article: http://www.creamjournal.org/pdf/CREAM_10_1_1.pdf
Impact factor: Not applicable
Emmanuel S. Baja
Institute of Clinical Epidemiology
National Institutes of Health
UP Manila
Validity Study of the Roll-Over Test and Risk Factors for Preeclampsia in Four Health Districts of Surigao City, Philippines, Acta Medica Philippina, 53(4): 344-349, 2019
Roll-over, a test to assess the risk of pre-eclampsia in pregnant women. A comparison of blood pressure is made with the woman lying on her left side and on her back; an excessive increase in blood pressure when she rolls to the supine position indicates an increased risk of pre-eclampsia. The test is performed between 28 and 32 weeks of pregnancy with the woman lying on her left side until the diastolic blood pressure. The roll-over test has gained some popularity because it is easy to perform, but its validity remains questionable. This study reassessed the validity of the roll-over test to screen women who will develop preeclampsia in the course of their pregnancies in a resource challenged community-based setting. The results of the study may be used by the rural health workers to determine and assess the early occurrence of pre-eclampsia among pregnant women particularly in those areas in the Philippines where scarcity of medical equipment is rampant. With this, maternal deaths may be avoided.
Significance:
Preeclampsia occurs in about 2% to 8% of pregnancies after mid-gestation. It is the most common medical complication of pregnancy whose incidence has continued to increase worldwide. Several factors have been previously incriminated as predisposing to the development of preeclampsia, namely age of the mother, previous preeclampsia, family history of preeclampsia, multiple pregnancy, pre-existing medical condition: insulin dependent diabetes, chronic hypertension, renal disease, autoimmune disease, antiphospholipid syndrome, parity, time between pregnancies, period of sexual cohabitation before pregnancy, maternal physical activity during pregnancy, previous abortions, miscarriages and stress. Early detection of preeclampsia will allow for more intensive antenatal surveillance, early management to avert complications such as seizure, cardiovascular and metabolic complications and even death. Screening pregnant women who are likely to develop preeclampsia during the course of their pregnancies is still the subject of many researches.
Link to the article: https://actamedicaphilippina.upm.edu.ph/index.php/acta/article/view/46
Impact factor: Not applicable
Charis Mae T. Neric1 and Cenon D. Elca1
1Department of Agricultural and Applied Economics, College of Economics and Management (UP Los Baños)
Screening for Collusion in the Philippine Chicken Meat, Chicken Egg, and Pork Markets,
Journal of International Society for Southeast Asian Agricultural Sciences, 25(1): 135-147, 2019
Chicken meat retail prices from 1990 to 2017 highlighting the effect of the entry of the Bounty Agro Ventures Incorporated in 2002, and the effect of smuggling in 2010
Pork retail prices from 1990 to 2017 highlighting the effect of San Miguel Corporation’s acquisition of the Pure Foods Corporation and the effect of smuggling
The paper tested for the possibility of illegal practices (i.e. collusion) of producers in the chicken meat, chicken eggs, and pork markets in the Philippines. This was done by identifying significant breaks (i.e. shifts) in the prices of these commodities from 1990 to 2017. It was found out that structural changes in the three industries and changes in output prices were related. Specifically, the analysis of retail prices of the three commodities showed statistically significant changes that correspond to important events like entry in and merger within the three industries.
The entry of a new player in and merger within the three industries may have accelerated the increase in prices. The effect of entry of a new player, however, is counter to economic logic since the increase in supply is expected to decrease prices. While these may seem beneficial to consumers, this issue has to be looked at in terms of its the effect on competition especially those involved in small-scale production. This study highlights the need for concerned agencies to devise measures to address the anti-competitive behavior of producers.
Significance:
Chicken meat, chicken eggs, and pork are regularly consumed by Filipinos, and as such, the market condition of these products including the available quantity of supply and the retail prices, as well as the current policy setting in the livestock and poultry industry, could significantly affect consumers. For instance, high prices offered by producers and market intermediaries would imply reduction of consumer welfare through lower consumption. Since prices are greatly influenced by the degree of competition in the market, increasing market competition through policy reforms could help lower prices and attract new customers. Thus, market competition aided by policy can help protect the welfare of both consumers and producers.
Moreover, since one of the concerns of the Philippine Competition Commission is to penalize anti-competitive agreements such as market collusion or the formation of cartel among industry players, the paper provides the essential first step in identifying which firms exhibit suspicious behavior and may be candidates for further scrutiny by concerned agencies.
Link to the article: http://issaasphil.org/wp-content/uploads/2019/06/13.-Neric-et-al-2019-Screening-for-Collusion-in-the-Philippine-Chicken-Meat-Chicken-Egg-and-Pork-Markets-FINAL.pdf
Impact factor: Not applicable
