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Volume 4, Issue No 4, December 2017 <<Previous Volume II Next Volume>>
Issues in Volume 4 Cover Page and Table of Contents Full Articles
Effects of String Tension to Fundamental Frequency of Sound and Body Vibration of Sape
Tee Hao Wong; Jackson Hian Wui Chang; Fuei Pien Che; Jedol Dayou. 2017. Transactions on Science and Technology, 4(4), 437 - 441 Abstract Sape is one of the popular stringed type traditional musical instruments in Sarawak, Malaysia. It was normally played to a form of ritualistic music to induce trance in the past. It is now gradually became a social instrument to accompany dances and for entertainment and therefore, there is a growing interest in this instrument. This paper discusses the effects of the string tension to the sound frequency and body vibration produced. This effect was investigated using three sapes made from the same wood but with different sizes. The study began by tuning the string of the instrument into three different tensions (high, medium & low). The string was plucked as in ordinary play which causes the body of the sape to vibrate, and at the same time generate sound. The sound signal was recorded using a microphone simultaneously with the body vibration signal using an accelerometer. These signals were then analyzed in MATLAB to obtain the fundamental frequency from the frequency spectrum. It was found that for high and medium string tension, the fundamental frequency of both the body vibration and sound of the sape give similar values. However, when the string tension is low, the fundamental frequency of the sound produced was higher compared to body vibration. This could be because string at higher tension modifies the vibrational mode of the sape body according to its frequency. View article
A Study on Tuaran River Channel Planform and the Effect of Sand Extraction on River Bed Sediments
Jayawati Montoi; Siti Rahayu Mohd. Hashim; Sanudin Tahir. 2017. Transactions on Science and Technology, 4(4), 442 - 448 Abstract River sand extraction is known as one of the main factors that induces the significant changes on river planform. This paper main objective is to study on the significance of planform changes on Tuaran River from 2003 to 2016 and sediment composition changes due to this activity. The study on channel planform focuses on four single wavelength channel bends which are located at the downstream of Tuaran River. Two meander features which are the channel width (w) and radius of curvature (Rc) were measured from digitized Google Earth satellite image year 2003, 2013, 2014 and 2016 and overlay with the Department of Survey and Mapping Malaysia (JUPEM) topographic map using Geographic Information System (GIS) software and georeferenced to World Geodetic System (WGS) 1984. Four sites which are located at the downstream of Tuaran River were selected to determine the river bed sediments composition. Three of the four sites are located at the sand extraction area whilst one site is a controlled area with no sand extraction activity. River bed sediments were collected and the sediments composition was analyzed using Mann Whitney and Kruskal-Wallis tests to determine the composition difference between the areas and the inner parts of the river. The analyses result showed that the pattern of channel planform changed throughout the years except between 2013 and 2014. Sand extraction activity altered river planform at a faster rate than normal river process where the reduction width of the river in this extraction area is significantly larger. Mann Whitney test on the river bed sediment shows that sediment composition is significantly differed with respect to the areas. Meanwhile, the Kruskal Wallis test showed that the area with no sand extraction has a significant difference in particles mean size between the outer bank, inner bank and middle part of the river unlike the area with active sand extraction. These findings proved that sand extraction activity has changed the river bed sediments distribution in extent changing the channel planform of the Tuaran River. View article
Runoff and Soil Erosion in Selectively-logged Over Forest, Danum Valley Sabah, Malaysia
Fera Cleophas; Baba Musta; Puah Mui How; Kawi Bidin. 2017. Transactions on Science and Technology, 4(4), 449 - 459 Abstract This study on soil loss and runoff using bounded runoff plot was carried out in selectively-logged over forest in Danum Valley Lahad Datu Sabah. The purpose of this study was to quantify the effect of forest cover disturbance and recovery on runoff and sediment production within the forest patches, and to better understand the key controlling factors. Runoff plots were set up in forest areas which experienced different levels of logging disturbances and recovery that has been logged 28 years prior to this study, i.e. logged hillslope, skid trail, and patches of undisturbed/control hillslope area. The magnitude of runoff and soil loss from skid track plot was found to be the highest (2.72 t ha-1 yr-1), followed by logged slope (2.56 t ha-1 yr-1) and control plot (0.13 t ha-1 yr-1). Physical properties of soil (ie: soil compaction) appeared to be important factor that determine the magnitude of soil loss. View article
The Monsoon Effect on Rainfall and Solar Radiation in Kota Kinabalu
Khan Vun Teong; Kartini Sukarno; Jackson Hian Wui Chang; Fuei Pien Chee; Chong Mun Ho; Jedol Dayou. 2017. Transactions on Science and Technology, 4(4), 460 - 465 Abstract Kota Kinabalu is located near the equator with a typically tropical climate, abundant rainfall, high and uniform temperatures, plentiful sunlight and high humidity that comes almost all year. The main economic activities in Kota Kinabalu such as agriculture, fishery, and tourism are highly impacted by the monsoon climate. This study analyzed the monthly time-variability of rainfall and solar radiation in Kota Kinabalu and monsoon temporal from October 2013 to September 2014. The daily average rainfall data were collected from Kota Kinabalu Meteorological Department, while, the solar radiation data with a ten minutes interval were obtained using LI-200 pyronometer. Subsequently, the maximum and minimum monthly average of solar radiation and cumulative rainfall were obtained. The paper examines the observed fluctuation of these variables and attempts to explain their possible relationship. The findings indicate that the period when the southwest monsoon season brings greater rainfall has lesser solar radiation. However, the level of solar radiation does not have an inverse relationship with rainfall amount. This could be due to the variation in air mass, short-term high-intensity rainfall or diurnal variation of rainfall. The city also received higher amount of rainfall in inter-monsoon period in October 2013 than that in the inter-monsoon in April 2014. This phenomenon happened due to the tail effect of typhoons that happen in Philippines. Sudden increases in wind speed up to average 33 km/h also happened during this inter-monsoon period. View article
Tropical Climate Constructed Wetlands as an Urban Stormwater Quality Improvement
Nur Asmaliza Mohd Noor; Lariyah Mohd Sidek; Kamisah Ariffin. 2017. Transactions on Science and Technology, 4(4), 466 - 475 Abstract The rapid development in an urban area can drastically change the land use and deteriorate the quality of source water. The contribution of higher intensity of rainfall will also worsen the problem and affect the quality of water. Constructed wetland is an essential component in improving the quality of stormwater and as an alternative method to reduce flood in urban area. It has been widely used in developed countries and temperate climate for the stormwater quality improvement. However, in Malaysia it can be considered as a new innovation and has not been widely implemented nationwide. The aim of this paper is to evaluate the function of constructed wetland in tropical climate as stormwater quality improvement with the experience from three constructed wetlands situated in Penang, Selangor and Kuala Lumpur in Malaysia. The data collected from these wetland systems used to treat stormwater runoff or runoff-impacted surface waters were examined and compared in order to identify any obvious trends that may aid future stormwater treatment wetland design efforts. The parameters measured and discussed in this paper are Total Phosphorus (TP), Biological Oxygen Demand (BOD), Total Nitrogen (TN), Total Suspended Solid (TSS) and Chemical Oxygen Demand (COD). The results indicate that the mean pollutant removal for BOD ranged from 8.73% to 39.03%, COD ranged from 11.74% to 27.66%, TSS ranged from -72.70% to 73.64%, TP ranged from 1.32% to 57.69% and TN ranged from 3.50% to 70.56%. The findings also indicate that the mean outlet concentrations for BOD, COD and TSS comply with the Water Quality Index Class II, thus far, partially fulfil the government’s policies. Findings from this study can be used significantly to enhance the knowledge in constructed wetland under tropical climate where it can serve effectively for managing urban runoff using control at source approach. View article
Lipid Distribution Associated With a Clandestine Grave: A Burial in Mangrove Soil
Xueer Chock; Siti Sofo Ismail. 2017. Transactions on Science and Technology, 4(4), 476 - 481 Abstract Locating clandestine grave is difficult using the traditional methods as it is time consuming, costly and involves a lot of human power. By determining the soil lipid distribution for each decomposition stages, the prior presence of a body in a grave can be confirmed and the estimated postmortem interval (PMI) can be established. In this study, fatty flesh of commercial pig (Sus Scrofa) was allowed to decompose under controlled laboratory experiment, mimicking a burial in a shallow grave. The fatty flesh was buried in mangrove soil under tropical climate. Soils were collected at eight designated sampling points, representing different decomposition stages. Lipids were extracted using Modified Bligh-Dyer Extraction Method and analyzed with Gas Chromatography-Flame Ionization Detector (GC-FID). The common lipids found were palmitic acid (C16:0), stearic acid (C18:0), oleic acid (C18:1) and cholesterol. Obvious difference in lipid content was observed in soil with and without burial. Lipid is a suitable burial biomarker for forensic scientists and law enforcements in solving crime cases. View article
Mapping Vegetation Cover of Acacia mangium Plantation by Age
Aqilah Nabihah Anuar; Ismail Jusoh; Affendi Suhaili; Mohamad Bodrul Munir. 2017. Transactions on Science and Technology, 4(4), 482 - 488 Abstract This paper aims to provide a method in mapping the vegetation cover of Acacia mangium plantation using the advanced survey technology of satellite remote sensing. This method would serve as an alternative to the conventional field sampling which is laborious and time consuming. Satellite images obtained from Landsat 8, provide the current view on vegetation cover of the whole plantation area. Two areas were targeted for the study which was area with A. mangium stands aged below 5 years old and another aged above 5 years old. Image analyses performed on Landsat 8 satellite image showed that vegetation coverage in area over 5 years old stands were significantly denser compared to within 5 years old stands. Low solar radiation (reflectance) was detected on area with high vegetation cover while higher radiation was detected on lesser vegetation cover. Overall findings of the study shows that the older A. mangium stand age greatly decreased the transmittance and reflectance of solar radiation in the visible light spectrum due to the increase in biomass. Hence, biomass played a key factor in distinguishing the vegetation covers between the two age classes (below 5 years old and above 5 years old). View article
Concentration and Time Dependent Cytotoxic effect of Methanolic Crude Extracts of Pseuduvaria macrophylla on the Human Cancer Cell Line
Atiqah Aziz; Mohd Zukiflee Abu Bakar; Farida Zuraina Mohd Yusof. 2017. Transactions on Science and Technology, 4(4), 489 - 497 Abstract The previous study demonstrated promising anti-cancer potential in methanolic crude extracts using single concentration, especially on breast cancer cells under 24 hours treatment. The present study investigates the effective concentration of bark and leaf methanolic extract on MCF-7 breast cancer cell line under 48 and 72 hours of treatment. The method employed was MTT assay to determine the half maximal inhibitory concentration (IC50) of both extracts at different concentration under 48 & 72 hours of treatment. The IC50 was obtained by plotting the concentration (µg/mL) versus the percentage of inhibition of each extract. The MCF7 cell line had decreased response to both extracts within 72 hours but showing promising cytotoxicity within 48 hours especially for leaf methanolic extracts at concentration of 140 µg/mL ± 0.23 to inhibit 50% of tested cancer cell line, meanwhile the medium inhibitory concentration (IC50) of bark methanolic extract on MCF7 cells was 242 µg/mL ± 0.13. The results showed that the the IC50 of leaf methanolic extracts was comparably lower than the IC50 of bark methanolic extracts. In fact, leaf methanolic extracts demonstrated better efficacy on the MCF7 after been treated within 48 hours compared to 72 hours. In other words, leaf methanolic extract more potent than bark methanolic extracts. View article
Pharmacophore Modelling of Phytochemicals from Clinacanthus nutans for Antimicrobial Activity
Tiara Nales Nyawai; Mohd Razip Asaruddin; Mohd Farhan Ariffeen Rosli; Ardy Mursyid Romli; Sam Ezekiel Radhakrishnan; Muhammad Norhelmi Ahmad. 2017. Transactions on Science and Technology, 4(4), 498 - 503 Abstract Pharmacophore modelling is incorporated as a part of approach in computer-aided drug design (CADD) which assists high-throughput virtual screening and drug design. It offers information on protein-ligand interaction as well as pharmacophore features responsible for interaction with the protein target. Current studies of phytochemicals isolated from Clinacanthus nutans Lindau locally known as belalai gajah are rich of flavonoids and phenolic compounds which able to induce antimicrobial activity. However, essential information of compounds activity against target protein is still inadequate. Hexane, ethyl acetate and methanol fractions of C. nutans showed no inhibition zone against Gram-negative bacterial strain namely Escherichia coli and Gram-positive bacterial strains namely Staphylococcus aureus and Salmonella typhimurium. Pharmacophore model generated from selected broad-spectrum antibiotics (cefixime, ampicillin, amoxicillin and ciprofloxacin) revealed features of hydrogen bond donor and acceptor, hydrophobic and aromatic ring. Six C-glycosyl flavones reported from literature have more similar features and higher fit-value to generated pharmacophore model. We recommend further study to determine minimum inhibitory concentration of C. nutans using various solvent extracts to justify claim of antimicrobial activity of this plant. Synergic effect and concentration of bioactive flavonoids against antimicrobial activity also need to be considered in future studies. View article
Above-ground Space Utilization and Feeding Guild of Tropical Rainforest Birds in Sarawak, Borneo
Sing-Tyan Pang; Attiqqah Fadziliah Sapian; Khatijah Ismail; Andrew Alek Tuen. 2017. Transactions on Science and Technology, 4(4), 504 - 512 Abstract Above-ground space within tropical rainforests harbour many bird species. However, the mechanism for their coexistence remains largely unknown. Avian feeding guilds are known to be good indicator of habitat specialization, but the details of how bird use of above-ground space, especially in reference to feeding remain unclear. Double-stacked mist-nets, with a total of six shelves and extending up to 3.6 metres above ground, were deployed at 30 forest sites in the Baram, Baleh and Pelagus regions of Sarawak, Borneo (East Malaysia). A total of 2,613 birds, comprising 124 species, were captured. Eight feeding guilds were identified, with insectivores being the most abundant. Most birds were captured at shelf 3 and 4, equivalent to 1.2 to 2.4 metres above-ground. Both the number of species and individuals captured in the shelves increased from the ground upwards to reach a maximum at shelf 3, after which it decreased. Insectivores were the most common guilds at the lowest two shelves, accounting for 68 % in shelf 1 and 47 % in shelf 2. This study shows that tropical forest birds are able to coexist in the relative safety of the above-ground space by exploiting different food resources indicating the importance of feeding guild in determining vertical stratification of avifauna species. View article
Growth and Yield of Acacia mangium Based on Permanent Sampling Plots in a Plantation
Ismail Jusoh; Joanna Kiung Suteh; Nur Syazni Adam. 2017. Transactions on Science and Technology, 4(4), 513 - 518 Abstract Acacia mangium is a very fast growing species belonging to the family fabaceae. It has been introduced in plantations in Sarawak, Malaysia for its rapid growth and wide range of adaptability. These plantations are anticipated to play the important roles in maintaining the commercial supply of logs thus reducing timber demand from the natural forests. Many plantations now used genetically improved material whose characters and properties have been improved through many years of research. Thus the study of growth and yield are crucial in order to have a more proper planning and management of this forest resource. This study assessed the growth and yield of the two acacias namely Acacia mangium superbulk or Acacia superbulk which is actually a second generation A. mangium and Acacia hybrid. The data obtained from permanent sampling plots (PSPs) of DAIKEN Plantation Sdn. Bhd. Bintulu were analysed to determine their mean annual increment (MAI) and periodic annual increment (PAI) in terms of diameter at breast height (DBH) and volume. Survival rate reduced as age of stand increased. Although DBH and height increased in size but the mean annual height and DBH increments decreased with age. The largest mean DBH recorded for Acacia superbulk and Acacia hybrid PSPs were 23.6 and 25.6 cm, respectively. Mean total height measured for Acacia superbulk and Acacia hybrid PSPs were 32.4 and 30.2 m, respectively. The highest volume mean annual increment was 27.4 m3/ha/yr (6.9 years old) and 26.5 m3/ha/yr (7.4 years old) for Acacia superbulk and Acacia hybrid, respectively. Initially growth in volume increased then began to decrease from seven years. Results of the four PSPs indicated that the maximum growth in volume per ha was attained at approximately seven years old stands. View article |