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UPSI Digital Repository (UDRep)
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| Latest addition to the database : |
| 2551 | 2023 Article | Phytochemicals and Antibacterial activity of Zingiber zerumbet growing in Negeri Sembilan, Malaysia Nur Atielia Preshahdin The present study is aimed at analysing the chemical composition of essential oil and screening the phytochemicals in crude extracts from the rhizomes of Zingiber zerumbet (L.) Roscoe ex Sm. (Zingiberaceae) as well as determining their antibacterial activity. The essential oil was extracted from the fresh rhizomes using the hydrodistillation method and analysed by gas chromatography-mass spectrometry (GC-MS). The phytochemicals from the dried rhizomes were extracted by sequential maceration technique using n-hexane, ethyl acetate, and methanol, while phytochemical screening was carried out using standard chemical tests. Antibacterial activity was screened using the disc diffusion method. A total of 31 components (94.5%) were detected in the rhizome oil with zerumbone (28.4%), terpinen-4-ol (16.5%) and α-humulene (11.1%) as the main components. Phytochemical screening of the extracts obtained from the dried rhizomes disclosed the existence of steroids, terpenes, quinones, flavonoids, p..... 376 hits |
| 2552 | 2023 Article | Perceptions of Genetics Difficulty among Science students Adelana, Owolabi P. This study examines the perceptions of genetics difficulties among science students in senior secondary schools. This became imperative due to the incessant poor performance of students in genetics, whose study holds tremendous promise for disease diagnosis, treatment, and prevention among men, animals and plants. Moreover, studies of this nature are scarce in Nigeria, hence the need to fill the existing research gap. To carry out the study, the descriptive survey research design was adopted. The sample comprised 351 biology students. Data was collected using “The Genetics Perceptions Questionnaire (GPQ) (r = .70). Descriptive statistical analysis of the data collected shows that while the majority (312, 88.9%; >11.1%, 39) of science students perceived genetics to be interesting, yet, they listed a lack of Biology laboratory for practical classes (x = 1.66, rated 1), not enough time to learn (x = 1.60, rated 2), and teacher’s poor teaching method (x = 1.56, rated 3), as factors aff..... 528 hits |
| 2553 | 2023 Article | Mathematical model development of Evacuated Glass-Thermal Absorber Tube Collector (EGATC) for air heating application Zairul Azrul Zakaria For decades, solar energy as one of the endless energy sources has become the most public preference as a means to accommodate space heating. Various studies on solar thermal technologies have been worked out to replace outdated systems. However, conventional solar thermal systems offer two drawbacks such as diffuse solar radiation conditions that can lead to insufficient heating during winter and autumn, and limitations of the solar collector orientation that need to be opposed at a correct tilted angle towards maximizing the performance of the system. Previous studies have proposed an integrated design that consists of the evacuated tube and a preheating double-pass flow thermal absorber arrangement, namely, Evacuated Glass-Thermal Absorber Tube Collector (EGATC) to overcome these problems. Therefore, this research has discussed further on the formulated mathematical modeling of the design. EGATC components used to convert solar radiation into heat that stabilized and increased the o..... 275 hits |
| 2554 | 2023 Article | Flavonoids from the Borneo Plant species Eusideroxylon zwageri Teijsm. & Binn. Muhammad Afiffikri Ahmad A new flavonoid, 7,3ˊ-dihydroxy-3,5,4ˊ-trimethoxyflavone, along with two known flavonoids,
7-hydroxy-5,4ˊ-dimethoxyflavone and 7-hydroxy-3,5,4ˊ-trimethoxyflavone were isolated from the leaves ethyl acetate extract of Eusideroxylon zwageri Teijsm. & Binn. (Lauraceae). Structures were elucidated by spectroscopic techniques such as NMR, IR, and Orbitrap Mass Spectrometry.
Keywords: Eusideroxylon zwageri, Lauraceae, flavonoid.. 533 hits |
| 2555 | 2023 Article | Development and effectiveness of I-Algebra module towards Malaysian year five pupils achievement and motivation S.W. Sathiyan Mooruthy S/O Subramaniam This study aims to develop and evaluate the effectiveness of the I-Algebra module, which employed the Normative Algebra Strategy (NAS). The development of the module was based on the adaptation of the Sidek model. The study also analyses the effect of the module on year five pupils' achievement and motivation. Quantitative approaches with the quasi-experimental design used for this study. Module was developed based the two phases stated in Sidek model, first phase is the draft phase of the module and the second phase is the phase that tries and evaluates the module. The module was evaluated by a panel of three experts to determine the content validity of the module. To determine the reliability and effectiveness of I-Algebra module, a pilot study was conducted which involved 30 year five pupils. The respondents were chosen using cluster sampling methods where they were divided equally into the treatment and the control groups. Data were analysed using SPSS software version 25 for infer..... 354 hits |
| 2556 | 2023 Article | Comparative Phytochemical and Antioxidant analysis of the leaf extracts of Two Nigerian medicinal plants Olalekan, Afolayan Michael Bridelia ferruginea (Benth., Euphorbiaceae), prominently found in Savannah regions, is commonly used as an ethnomedicine for the treatment of several ailments in many parts of Africa. Piliostigma thonningii (Schum., Fabaceae) is used for various medicinal purposes in African countries with some pharmacological activities established from the crude extracts including antibacterial, antihelminthic, antiinflammatory and antilipidemic activities. In the present study, crude methanolic extract and fractions of B. ferruginea and P. thonningii were examined for their phytochemical constituents and antioxidant activity using standard protocols. Qualitative phytochemical screening of B. ferruginea crude extract revealed the presence of tannins, saponins, phlobatanins, flavonoids, steroids, alkaloids, glycosides, phenols and resins while it tested negative for triterpenoids, carbohydrates, terpenoids and anthraquinones; the quantitative phytochemical analysis showed that it contained 1.5% saponi..... 555 hits |
| 2557 | 2023 Article | Chemical composition of the Essential oil of Litsea resinosa blume and acetylcholinesterase activity Abubakar Siddiq Salihu The essential oil of Litsea resinosa Blume (Lauraceae) was obtained by hydrodistillation and was fully characterized by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). A total of twenty-eight components were identified in the essential oil, which made up 90.8% of the total oil. The essential oil consists mainly of β-caryophyllene (22.5%), α-humulene (15.4%), caryophyllene oxide (9.2%), germacrene D (5.6%), and β-selinene (5.0%). The essential oil showed significant activity against acetylcholinesterase with a percentage inhibition of 72.4%.
Keywords: Litsea resinosa, Lauraceae, essential oil, caryophyllene, acetylcholinesterase.. 468 hits |
| 2558 | 2023 Article | Antimalarial assessment of certain 1,2,4-Triazoles and Benzoquinolones against Plasmodium knowlesi A1H1 Nurul Syafiqah Rezali Previous studies have reported the use of nitrogen-heterocyclic compounds to treat malaria. Interestingly, quinolone and 1,2,4-triazole scaffolds demonstrated an outstanding capacity to target at least two stages of the malaria parasite life cycle, especially when they are hybrid with other nitrogen heterocycles. Thus, the objective of this study is to assess the drug susceptibility of Plasmodium knowlesi A1H1 parasites to certain 1,2,4-triazoles and benzoquinones that bear pyrrolidinones using a plasmodium lactate dehydrogenase assay. All synthesized compounds showed moderate activity against P. knowlesi A1H1 with EC50 values in the range of 13.39-28.85 μM. Both 1,2,4-triazoles and quinolone derivatives were synthesized using commercially available pyrrolidinones.
Keywords: 1,2,4-Triazoles; quinolones; antimalarial, Plasmodium knowlesi A1H1.. 613 hits |
| 2559 | 2023 Article | Agent Navigation based on Boundary Value Problem Using Iterative Methods Farhah Athirah Musli This paper presents the simulation of numerical solutions to the navigational problem of an agent traveling safely in its environment. The approach is based on the numeric solutions of the boundary value problem (BVP) that generate harmonic potential fields through a differential equation whose gradient represents navigation routes to the destination. Two methods, namely KSOR and KAOR, were tested to solve the BVP. KSOR and KAOR are variants of the standard SOR and AOR methods, respectively. In this work, the KSOR and KAOR methods were used to solve the BVP by applying Laplace's equation to obtain harmonic functions. The generated harmonic functions are then utilized by the searching algorithm to find a smooth navigational route for an agent to travel in its environment without colliding with any obstacles. The numerical results from the solutions of BVP demonstrate that the KAOR provides a faster execution time with fewer iterations compared to the KSOR method.
Keywords: KSOR, KAOR, ..... 565 hits |
| 2560 | 2023 Article | A stability analysis for Radiation Effects on Marangoni Convection boundary layer over a permeable surface Nor Azian Aini Mat The objectives are to derive the stability analysis theoretically and to set up the stability analysis
numerically for radiation effects on Marangoni convection boundary layer over a permeable
surface. The stability analysis is used to determine which branch solutions are stable and
physically realisable. The stability can be tested via the smallest eigenvalue. Negative smallest
eigenvalue produces an initial growth of disturbance and the flow becomes unstable. In contrast,
the positive smallest eigenvalue results in an initial decay of the disturbance, thus the flow is
stable. The research has an implication in order to identify which solution is stable, whether the
first or the second solution.
Keywords: permeable surface, dual solution, stability analysis.. 538 hits |
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