Manila Journal of Science 10 (2017), pp. 101-114

Status of Coral Communities and Reef-Associated Fish and Invertebrates in Batangas and Northern Palawan

Abstract

The present study shows the status of certain reefs of Batangas and northern Palawan using data gathered with volunteers, community members, local governments, and civil society groups utilizing Reef Check® methods. Both provinces have mean densities of less than 1 per 100 m2 for most of the fish and invertebrate indicators—signifying that they are overfished. Read More

Manila Journal of Science 10 (2017), pp. 87-101

Diversity and Phylogenetic Relationships Among Isolated Root Symbiotic Fungi from Drynaria quercifolia L. in La Union, Philippines

Abstract

Drynaria quercifolia is an epiphytic fern often exposed to water- and light-stressed environments. One distinct ecophysiological adaptation of epiphytic ferns is their symbiotic relationship with fungi. This is the first study undertaken to explore the phylogenetic relationship, colonization, occurrence rate, and diversity of RSF found in D. quercifolia. Two hundred seventy-eight RSF isolates were collected from 300 representative root segments. Genomic DNA of the RSF was extracted, and the ITS (internal transcribed spacer) region of the 18S ribosomal DNA (rDNA) was sequenced. Thirteen species were recorded. Eight of the 13 RSF were identified up to the species level using the Basic Local Alignment Search Tool nucleotide search program (BLASTn) to their closest type match available on the databank of NCBI. However, five RSF were undescribed. Read More

Manila Journal of Science 10 (2017), pp. 75-86

Sponsored Game With Fuzzy Coalitions

Abstract

Sponsorship is a way of expressing support where an individual or group gives provision (financial or in other forms) to an event, activity, person, or organization. When it comes to business, the two involved parties in a sponsorship are expected to engage in a mutual trading relationship so that each one expects to gain some benefit. In 2012, Nocon’s study introduced a game that models sponsorship, called sponsored game. In this type of game, there are two sets of players: the sponsors and the team players. Read More

Manila Journal of Science 10 (2017), pp. 65-74

A Study of Knowledge, Attitude, and Practices Regarding Malaria Among Inhabitants of Ezinihite Local Government Area, Imo State, Eastern Nigeria

Abstract

Accurate knowledge, attitudes, and practices of the individuals of a community remain vital to effective malaria control. The study assessed the knowledge, attitudes, and practices regarding malaria among respondents in selected communities of Ezinihite L.G.A. of Imo State using structured questionnaires. Four communities in Ezinihite L.G.A with indigenous malaria cases were randomly selected. All the household heads were visited prior to the study. A total of 443 respondents from the four communities participated. Sociodemographic data showed that the respondents were of different age groups and educational, marital, and occupational status. Read More

Manila Journal of Science 10 (2017), pp. 44-63

Quantum Chemical Studies on Corrosion Inhibition of 1, 3-Thiazine Derivatives for Mild Steel in Acidic Media: DFT Approach

Abstract

Quantum chemical calculations via B3LYP/631G(d.p) level were performed on 1,3-Thiazine derivatives used as corrosion inhibitors for mild steel in acidic media. The calculated molecular properties such as the highest occupied molecular orbital energy (EHOMO), Lowest unoccupied molecular orbital (ELUMO), chemical hardness (ŋ), energy band gap (Eg), dipole moment, electronegativity (χ), fraction of electron transfer (ΔN), and global nucleophillicity index (ω) were correlated to the observed corrosion efficiency. Read More

Landslide Susceptibility Mapping

Landslide Susceptibility Mapping in a Geologically Complex Terrane: A Case Study From Northwest Mindoro, Philippines

Abstract

Northwest Mindoro is underlain by inherently weak materials that are the product of arc-continent collision involving the Philippine Mobile Belt and the Palawan Microcontinental Block. Consequent to having an arc-continent collision setting, the frequent exposure to precipitation and the human-induced pressure on the environment is the occurrence of landslides in the island. Because of the complicated tectonic makeup of the area and the complex controls to slope failures, a variety of approaches to landslide susceptibility assessment was used and compared. Read More

Manila Journal of Science 10 (2017), pp. 16-24

A Sum Labelling for Some Families of Unicyclic Graphs

Abstract

In 2008, H. Fernau et al. provided an optimal sum labelling scheme of the generalized friendship graph and showed that its sum number is 2. The generalized friendship graph is a symmetric collection of cycles meeting at a common vertex. This graph fq,p may also be viewed as a graph obtained by considering several copies of a cycle and identifying a vertex from each cycle and merging them into a single vertex. Read More

Manila Journal of Science 10 (2017), pp. 1-15

Oscillation Propagation in a Two-Dimensional Lattice of Mutually Repressive Nodes

Abstract

Concurrent decision-making networks represent decision systems where the utility of a component (node) becomes dominant by repressing other nodes. These networks are commonly used in modeling competitive interactions in the computational, biological, and social sciences. Most of the existing studies about concurrent decision-making focus on equilibrium convergence of the utilities. However, there are many cases where oscillations can arise. Here, we consider concurrent decision-making networks that follow a two-dimensional lattice topology where one node is a source of oscillations. Read More

Arboleda

Density Functional Theory–Based Study of the Structural Properties of Hexagonal Boron Nitride/Graphene Hetero-Bilayer and Silicene/Hexagonal Boron Nitride/Graphene Hetero-Structures for Thin Film Transistor Applications

Abstract

The geometric properties and structural stability of hexagonal boron nitride on graphene (h-BN/G) hetero-bilayer and silicene on hexagonal boron nitride on graphene (Si/h-BN/G) hetero-structure were investigated using density functional theory. The calculations were performed through the Vienna Ab Initio Simulation package (VASP) implemented with three different approximations, namely, the local density approximation (LDA), general gradient approximation (GGA), and GGA with Tkatchenko–Scheffler van der Waals (vdW) correction. In reference to the experimental interlayer distance and binding energy between graphitic layers, the h-BN/G hetero-bilayer and Si/h-BN/G hetero-structures were stable. Read More