Malaysian Journal of Science 2023-06-28T16:32:08+08:00 Prof. Dr. Wan Haliza binti Abd Majid Open Journal Systems <p style="text-align: justify;">Malaysian Journal of Science (MJS) is the official peer-reviewed open-access journal of the <a href="">Faculty of Science, Universiti Malaya</a>. Effective from the year 2020 onwards, the frequency of regular issues publication is three times a year. MJS is indexed in <a href="">Scopus</a>, <a href=";as_sdt=0%2C5&amp;q=Malaysian+Journal+of+Science&amp;btnG=">Google Scholar</a>, <a href="">Chemical Abstracts Service Database</a>, <a href="">ASEAN Citation Index (ACI)</a>, and <a href="">MYCite</a>.</p> <p style="text-align: justify;">MJS is a reputable journal with a growing audience, which focuses on current developments in all disciplines of science. The journal publishes original articles, review articles, short communications, and case reports that are of importance to the scientific community. </p> <p style="text-align: justify;"><strong>eISSN : 2600-8688<br /></strong><strong><strong>Print ISSN : 1394-3065<br /></strong></strong><strong><strong>Publisher : Faculty of Science, Universiti Malaya</strong></strong> </p> WHAT IS THE TRUE CARBON FRACTION VALUE OF MANGROVE BIOMASS? 2022-06-23T15:40:11+08:00 Rahman Maryono Oktavia Nurmawaty Sigiro <p>Carbon stock in mangrove stands is estimated through the biomass approach multiplied by the value of the mangrove carbon fraction. Many researchers use the value of 47% as the carbon fraction value for all mangrove species which should be based on the actual carbon content value. The research was conducted using the literature review method using a database ScienceDirect and Google Scholar until 2022. The search strategy was carried out using keywords: mangrove biomass, mangrove carbon stock, organic carbon of mangrove, carbon fraction of mangrove biomass, and chemical composition of mangrove biomass. The results showed that the value of the carbon fraction with the approach of organic carbon content was 46.4% and lower than the value of the carbon fraction with the approach of compounds making up mangrove biomass, which was 46.82%. This value was contributed by carbohydrates at 26.20%, amino acids 2.97%, tannins 3.22%, lignins 3.38%, fatty acids 7.69%, triterpenoids 3.17%, and n-alkanes 0.19. %. The estimation of mangrove carbon stock in forests with homogeneous species can use the value of carbon fraction in each mangrove species, namely 46.3% for <em>B. gymnorrhiza</em>, 45.9% for <em>R.</em> <em>apiculata</em>, and 47.1% for <em>S.</em> <em>alba</em><em>. </em>Meanwhile , a carbon fraction value of 46.82% can be used for all true mangrove species to estimate the carbon stock in forests with heterogeneous mangrove species.</p> 2023-06-28T00:00:00+08:00 Copyright (c) 2023 Malaysian Journal of Science DETERMINATION OF URANIUM CONCENTRATIONS IN RICE SAMPLES AVAILABLE IN THE IRAQI MARKET USING THE CR-39 DETECTOR 2022-11-01T12:47:07+08:00 Auday Al-Bayati Adawiya Alwan Hussein A. Miran <p>&nbsp;In this study, the results of the uranium concentrations and specific activity in 10 rice samples are described using a solid-state track detector (CR-39). Samples were collected from various local Iraqi markets with different origins (Iraq, India, America, and Thailand). Our findings found that the results of uranium concentration in all studied samples are ranging from (0.55 ± 0.28 to 1.74 ± 0.31) ppm with a weighted average of (1.24 ± 0.99) ppm. Also, results demonstrate that the specific activity values of the studied samples swing between values of (6.88 ± 3.52 and 21.49 ± 3.85) Bq/Kg. The obtained results of the studied rice samples are indicated that it is less than the acceptable limit of those studies established by many organizations such as the United Nations scientific committee on the effects of atomic radiation (UNSCEAR), the international atomic energy agency (IAEA), the world health organization (WHO), and others.</p> 2023-06-28T00:00:00+08:00 Copyright (c) 2023 Malaysian Journal of Science THE EFFECTIVENESS OF APPLICATIONS OF BETEL (Piper Betel Linn.) LEAF EXTRACT AND BACTERIOCIN FOR TEAT DIPPING DURING MILKING HANDLING IN INDONESIAN DAIRY FARMING 2022-06-23T14:15:41+08:00 Iyep Komala Irma Isnafia Arief Afton Atabany Lucia Cyrilla ENSD <p>This study aims to investigate the effectiveness of teat dipping using sirih leaf extract (Piper betle) and bacteria in dairy farms located in Cijeruk Subdistrict, Bogor Regency, West Java. The research employs an experimental design utilizing a Completely Randomized Design (CRD) with four treatments: (1) teat dipping with masofilm (2% iodine) as the positive control, (2) teat dipping with bacteriocin (protein content = 11.17 g mL-1) (P1), (3) teat dipping with betel leaf extract (25% concentration-based) (P2), and (4) teat dipping without any additional treatment, serving as the negative control. Each treatment is replicated three times. The observed parameters include the reduction in somatic cell count (SCC) and total plate count (TPC) in cow's milk. Data were collected through sampling from 12 cows and analyzed using milk quality analysis to assess the conditions of dairy farms in Cijeruk Subdistrict.</p> 2023-06-28T00:00:00+08:00 Copyright (c) 2023 Malaysian Journal of Science THE BENEFITS OF FERMENTED GOAT’S MILK WHEY MASK WITH HONEY AND RED FRUIT (Pandanus conoideus) AS ANTIOXIDANT AGENT 2023-01-25T09:59:45+08:00 Yulia Yasmin Pratiwi Irma Isnafia Arief M.Sriduresta Soenarno <p>Goat’s milk fermented whey, honey, and red fruit extract can be used for making face masks because they can increase the effectiveness of mask. Whey has smaller fat globules so it helped nutrients absorbed better in to the skin, the honey and red fruit contain flavonoids and phenolics to keep skin moist, clean, and it also produced the antioxidant properties of fermented whey masks. This study aimed to determine the formulation of the fermented whey mask as well as its physical characteristics and antioxidant properties. Fermented whey masks were tested for their physical characteristic such as pH, water activity, spreading ability, drying time and antioxidant properties to see which formulation produced a mask with good test results. The study was tested using a completely randomized factorial design. Result showed that mask with addition of 10% honey had better physical characteristic such as pH, water activity, spreading ability, drying time and antioxidant activity than the addition of 5% honey. Results gained from this study were prospected to be developed into the shelf life stability and dermatologically because it has the potential to be developed commercially.</p> 2023-06-28T00:00:00+08:00 Copyright (c) 2023 Malaysian Journal of Science SLOW AND FAST SUBSYSTEMS FOR COMPLEX UNCOMPETITIVE INHIBITOR MECHANISMS 2022-07-09T22:58:29+08:00 Honar Hamad Sarbaz Hamza Abdullah Khoshnaw Muhammad Shahzad <p>To fully understand intricate enzyme reaction models, one must explore beyond the confines of chemical and biological tools and look toward mathematical modeling and model reduction techniques. Mathematical modeling and model reduction techniques have the potential to provide a vast array of analysis tools for such models. This piece of work entails a review and discussion of a complex noncompetitive inhibitor model. This model is composed of seven non-linear differential equations with constant rates. We propose two efficient model reduction techniques: quasi- steady-state approximation (QSSA) and quasi-equilibrium approximation (QEA). By utilizing the suggested methods, the model equations are segregated into slow and fast subsystems, leading to the attainment of reduced models and slow manifolds with fewer variables and parameters. The outcomes manifest some analytical approximate solutions for the proposed model and establish a profound agreement between model dynamics for both the original and the reduced models. Observing that the reduced models can accurately identify certain critical model parameters is intriguing.</p> 2023-06-28T00:00:00+08:00 Copyright (c) 2023 Malaysian Journal of Science SOLUTION OF ORDINARY DIFFERENTIAL EQUATION vvi (u)=f(u,v,v',v'',v''') USING EIGHTH AND NINTH ORDER RUNGE-KUTTA TYPE METHOD 2022-12-28T16:44:24+08:00 Manpreet Kaur Sangeet Kumar Jasdev Bhatti <p>The present paper presents the numerical conclusion to solve sixth order initial value ordinary differential equation (ODE). The concept of order conditions for three stage eighth order (RKSD8) &amp; four stage ninth order Runge-Kutta methods (RKSD9) has been derived for finding global truncation error of differential equation The global and local truncated errors norms, zero stability of extended Runge-Kutta method (RK) is well defined and demonstrated with the help of an example.</p> 2023-06-28T00:00:00+08:00 Copyright (c) 2023 Malaysian Journal of Science EVALUATION OF Zr, Ni-Cr, And Au-Ag APPLIED MATERIALS USING FEM ON PROSTHETIC CROWNS 2022-03-29T17:10:36+08:00 P Vicky Kumar Anil Kumar Birru Nelson Muthu <p>The crown is a steady prosthesis designed to restore the functionality of a damaged tooth along, with its shape and size. They are also used to reinforce the tooth that poses long-term risk due to wide cavities and accidental injuries. The crowns are fixed using dental cement made of different materials such as porcelain cement, ceramics, etc. The present work aims to assess the mechanical properties – stiffness and strength, of the single molar crown prosthetic tooth materials to determine the efficacy of each material under typical masticatory load observed in clinical settings. To this end, the finite element method (FEM) is used to analyze the mechanical behavior of the molar crowns made of Zirconium (Zr), Nickel Chromium (Ni-Cr), and Gold alloy (Au-Ag). The crown models were created in Solidworks and exported to the ANSYS FE package. The exported three-dimensional models were subjected to varying loading conditions – vertical and oblique forces to the tooth axis under suitable displacement boundary conditions. Due to a relatively high elastic modulus, the Zr and Ni-Cr alloy exhibited a higher stress concentration and lower deformation on the crown’s intaglio surface compared to the Au-Ag alloy.</p> 2023-06-28T00:00:00+08:00 Copyright (c) 2023 Malaysian Journal of Science SPECTRAL AND STRUCTURAL ANALYSIS FOR SODIUM SILICATE-BASED AEROGEL VIA NORMAL DRYING PRESSURE 2022-08-29T17:27:42+08:00 Wasan H. Al-husseny Israa F. Al-Sharuee Ban R. Ali <p>Five types of silica aerogel were prepared at ambient pressure: sodium silicate, TEOS, and sodium silicate, with TEOS utilized as precursors. We investigated the effects of catalysis, mixing water or ethanol with the precursors, as well as the procedure of modification. Aqueous is a low-cost alternative, and many applications utilize it. A manufacturing colloidal silicic acid hydrosol was created from the ion exchange of an industrial water glass. The properties of physical, chemical, and hydrophobicity were examined via density, XRD, FTIR, and contact angle. BET, FESEM, and EDS analysis determined the structural properties. The silica hydrogel's pore liquid (H<sub>2</sub>0) was successively removed. The spectral properties confirmed the modification by the derived high contact angle of 152º, low transparency, and amorphous structure. The resulting aerogel monoliths have a well-developed mesoporous structure, a large specific surface area of 961 m2/g, and a low density of 0.04 g/cm3.</p> 2023-06-28T00:00:00+08:00 Copyright (c) 2023 Malaysian Journal of Science ANNUAL EFFECTIVE DOSE ESTIMATION DUE TO THE NATURAL RADIOACTIVITY IN YAM TUBERS (Dioscorea rotundata) CULTIVATED IN NORTHCENTRAL NIGERIA 2022-08-21T11:47:18+08:00 Matthew Tikpangi Kolo Oyeleke Ismail Olarinoye Simon Olonkwoh Salihu Hauwau Kulu Shuaibu Funmilayo Ayedun <p>Yam tubers (<em>Dioscorea rotundata</em>) and soil from commercially cultivated farmland in northcentral Nigeria were collected and investigated for their natural radioactivity content using a 3” × 3” NaI(Tl) gamma detector. Average activities of <sup>238</sup>U, <sup>232</sup>Th and <sup>40</sup>K in the investigated farm soil were 38.13±3.76 Bq kg<sup>-1</sup>, 15.06±0.99 Bq kg<sup>-1</sup> and 381.80±15.50 Bq kg<sup>-1,</sup> respectively. The results agree with the world’s acceptable levels of safety. Activities measured in the yam tubers were in the range from BDL -76.68±9.73 Bq kg<sup>-1</sup> for <sup>238</sup>U, BDL - 19.77±1.30 Bq kg<sup>-1 </sup>for <sup>232</sup>Th and 312.50±20.73 - 627.94±38.37 Bq kg<sup>-1</sup> for <sup>40</sup>K, with average values of 29.23±4.0, 13.10±0.72 and 445.10±27.20 Bq kg<sup>-1,</sup> respectively. The total effective dose from radionuclide intake from yam ingestion fluctuated between 272.12 μSv y<sup>-1</sup> and 935.97 μSv y<sup>-1</sup>. Correlation analysis identified <sup>238</sup>U and <sup>232</sup>Th as the leading contributors to the total effective dose from ingesting yam tubers cultivated in northcentral Nigeria.</p> 2023-06-28T00:00:00+08:00 Copyright (c) 2023 Malaysian Journal of Science THE STRUCTURE OF THERMOLUMINESCENCE TRAPS IN AQUEOUS GROWN KCl 2022-10-13T22:15:47+08:00 Ruchi Pandey Rajendra Kumar Sumit Tiwari S. D. Pandey <p>The results of TL studies in aqueous grown undoped KCl crystals are reported. A de-convolution of TL curve into five component peaks has been performed and trap depths have been obtained. The importance of bi-vacancy has been established as a fundamental trap and its anion vacancy end has also been proposed as a suitable trap for thermoluminescence in KCl crystals. The traps at anion vacancies linked to impurity vacancy I-V pairs have also been envisaged and the shift in the depths of traps is attributed to the electric field of I-V pairs in the lattice caused by inherent divalent ions. Some traps linked to hydroxyl groups have also been identified.</p> 2023-06-28T00:00:00+08:00 Copyright (c) 2023 Malaysian Journal of Science