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- PublicationSynthesis Of Novel Carbon Dots From Polyalthia Longifolia Leaf For In Vitro Cytotoxicity Against Hela Cells(2024-09)Carbon dots (CDs), known for their outstanding fluorescence properties, have found extensive applications in medicine and pharmacy owing to their biocompatibility and nano-sized attributes. However, the potential cytotoxic effects of CDs derived from Polyalthia longifolia rich with various pharmacological activity remain underexplored. To address this gap, the current study synthesized, characterized, and investigated the toxicity against RAW264.7 cells, as well as photoinduced cytotoxicity against HeLa cells of the CDs derived from P. longifolia. Various methods, including transmission electron microscopy (TEM), X-ray diffraction (XRD), ultraviolet-visible (UV-vis) spectroscopy, zeta potential, and Fouriertransform infrared spectroscopy (FTIR), were employed to characterize the CDs. Additionally, the toxicity of the synthesized CDs was evaluated against RAW 264.7 cells, and the photo-induced cytotoxicity was assessed against HeLa cells under white light. Moreover, the impact of photo activation on ROS generation in HeLa cells also investigated. The synthesized spherical black spheres exhibited an average size of 6.29 ± 0.31 nm (TEM), consisting of both crystalline and amorphous phases of carbon (XRD), and a negative zeta potential of -20.7 ± 2.01 mV. The synthesized CDs emitted blue fluorescence when exposed to UV light at 365 nm and exhibited a prominent UVvisible absorption peak in the UV region. FTIR analysis revealed the existence of diverse functional groups on the CDs. The toxicity evaluation of synthesized CDs indicated low toxicity, promoting RAW264.7 cell viability within the 500–8000 μg range (P<0.05).
- PublicationTeachers’ Attitude And Teaching Practices Towards Entrepreneurial Skills: An Exploratory Study On Middle School Science Teachers Of Sindh Province, Pakistan(2024-08)There is an increasing demand for entrepreneurial skills. The World Economic Forum has established that the majority of the work activities will be automated by the year 2055, creating more complex roles and challenges for future employees. As there is a rise in the number of unsuccessful employees in Pakistan, that is a concern about introducing entrepreneurial skills at the school level. In the case of Pakistan, entrepreneurial skills are emphasized as one of the significant aspects of the middle-level curriculum. However, in schools, particularly in government schools, students are lacking entrepreneurial skills. Science is considered one of the pivotal subjects to develop students’ entrepreneurial skills. The interrelation of entrepreneurial skills and science education in this study portrays the associative nature of both areas. This study accentuates that students with a strong background of scientific knowledge and a solid grasp of entrepreneurial skills are more well-equipped for the demands of the modern world workforce and can enliven innovative ideas. In fulfilling these responsibilities, a teacher should hence have entrepreneurial essence and skills. The attitude and teaching practices of science teachers reflect their entrepreneurial skills. For the purpose of exploring the attitudes and teaching practices of science teachers, this study adopted a qualitative exploratory research approach. An exploratory design enables active participation of the participants, allowing them to generate new knowledge. A purposive sampling approach was employed in selecting the 14 participants who fulfilled the criteria.
- PublicationTertiary Education Trust Fund’s Intervention In The Training And Development Of Academics In Nigerian Public Universities(2024-09)Public universities in Nigeria are confronted with a mirage of challenges which include: a shortage of qualified academics, low research output, poor global ranking and unaccredited academic programmes, et cetera. Therefore, TETFund intervention in the training and development of academics of public universities through study fellowship, sponsorship of conference attendance and institutional-based research became imperative, given the New Public Management (NPM) that emphasises effectiveness, efficiency and economy. The main objective of this research is to assess the contribution of TETFund’s intervention in the training and development of academics at public universities in Nigeria. The institutional theory that emphasises isomorphism and a balanced scorecard model of performance measurement guided the research. The mixed-methods approach affords the use of both quantitative (questionnaire) and qualitative (interview) means of data collection simultaneously, and subsequently allows integration while discussing the finding through triangulation. Multiple regression analysis was used as statistical tools of analysis with the help of Statistical Package for Social Sciences software while the Nvivo 12 software was used to analyse the interview data obtained. The result revealed that there is a positive outcome as a result of the intervention which includes an increased number of qualified academics and improved global ranking. It also highlighted the inhibiting factors to the performance of the contribution of the intervention. The study recommended among other things that electronic means of communication be deployed in a complementary manner to the usual means (hard copies) so that documents that need to be submitted are done electronically to ensure that delays of submission are reduced to the barest minimum while approval and release of funds happen promptly. It concludes that TETFund intervention has contributed positively to the training and development of university academics. However, there is room for improvement to enhance better service delivery in Nigerian public universities.
- PublicationEffect of molecular structures and concentration of hardener on thermal characteristics of epoxy underfill(2024-08-02)The reliability and performance of electronic packaging is greatly dependant on the underfill material. The underfill material operate as a barrier to keep out environmental elements like moisture, pollutants, and mechanical harm. On the other hand, variables like curing temperature and molecular structure could have an impact on the curing rate of the underfill materials which determines its qualities and performance. In this work, the effect of different molecular structures (i.e. linear and aromatic) and anhydride hardener’s concentration (i.e. 1.0 and 1.5 weight ratio) of the underfill materials on the thermal behaviour were compared, characterised and studied in anhydride-epoxy curing system. The chemical, physical, and thermal properties of the underfill material were evaluated using Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), hardness test, and optical image. It could be observed that all epoxy underfills in this study were completely cured by the disappearance of peaks at 1848 – 1774 cm-1 and 887 cm-1 in the FTIR spectrum that correspond to the anhydride and epoxy respectively. From the DSC and TGA analyses, it was found that the molecular structure (i.e. aromatic and linear) contributes to the thermal stability and flexibility of the epoxy underfill in the DSC. The glass transition temperature (Tg) could be observed at -2oC for EPM (Epoxy-Polyethylene Glycol-Maleic Anhydride) and none in the EHM (Epoxy-Hydroquinone-Maleic Anhydride) for the temperature range of 25 to -40 oC. This is due to the linear molecular structure that contributing to the easier chain segment movement between the crosslinks while the aromatic restricted the chain movement thus increasing the Tg. Moreover, hardness studies indicate that aromatic structure (EHM) is harder than linear structure (EPM). This is further supported by the optical picture, which indicates that EPM is more flexible than EHM. Additionally, it has been determined by DSC, TGA, and hardness tests that the presence of aromatic and linear structures would affect the thermal and physical performance.
- PublicationLow-cost condition monitoring for unbalanced motor systems using tuned dynamic vibration absorber(2025-02)Unbalanced motor is referred to the situation of a rotating system where there is an uneven distribution of mass, resulting the significant vibration or imbalance problems. Poor management of unbalanced motor can lead to various issues, such as increased vibration, decreased efficiency, and potential damage of both motor and the integrated system. This study investigates the performance of reduction vibration for an integrated unbalanced motor-beam structure using a Tuned Dynamic Vibration Absorbers (TDVA), with different types of TDVA stiffness (stainless steel, aluminium, brass and titanium). To gain a better nderstanding of the system dynamic behavior, the natural frequencies of the beam were determined using an Experimental Modal Analysis prior to implementing the TDVA. The Operational Deflection Shapes (ODS) experiment was conducted in the z-axis direction with three different motor speeds; 880 RPM (14.8 Hz), 2100 RPM (35 Hz) and 2800 RPM (46.5 Hz) to observe the most significant vibration of the beam during operation. Later, the TDVA which consisted of two secondary masses, was employed to modify the structural dynamic response of the beam. The lengths of the TDVA masses were adjusted based on the motor speed to optimize vibration reduction of the beam. The selection of TDVA stiffness materials was driven by their varying densities, moduli of elasticity and damping capacities, providing insight into their suitability for specific operating frequencies and conditions. Various TDVA stiffness materials were applied to determine the most effective vibration attenuation and it was found that aluminium material has produced the highest attenuation of 93.18 % at motor speed of 2880 RPM. Furthermore, a low-cost condition-based monitoring (CBM) system was developed using an Arduino Uno microcontroller connected to a Raspberry Pi. This system utilized an MPU9250 sensor which is cost-effective and appropriate for vibration measurement. The CBM system dashboard was hosted using the cloud, allowing real-time access to the vibration data. The system employed four programmable conditions to continuously assess the vibration activities. This affordable approach offers an accessible solution for small-scale industries, reducing reliance on expensive industrial-grade analyzers. In the event of abnormal vibration, the CBM system can trigger a notification alert, serving as a preventive measure against structure failures. The findings contribute to broader applications, including the improvement of maintenance strategies across various industries, emphasizing the transformative impact of combining effective vibration control and low-cost monitoring systems. It is also contributes to the understanding of the effect of different TDVA stiffness materials on the vibration control of beam structures with the additional of practical approach for real-time condition monitoring to improve system reliability.
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- ItemMorphological, Pathogenic, Genetic And Molecular Variabilities Of Fusarium Spp., The Pathogens Of Asparagus Crown And Root Rot In Malaysia And Brunei Darussalam(Universiti Sains Malaysia, 2006-04)Asparagus (Asparagus officinalis) is becoming more important in South East Asia (SEA) and quickly becoming a preferred vegetable. All varieties planted throughout SEA have been and now are still facing the most destructive disease i.e. asparagus crown and root rot. The main aim of the thesis was to collect and isolate Fusarium spp. from asparagus plants showing crown and root rot symptoms and their soils in Malaysia and Brunei Darussalam. The other objectives were to evaluate pathogenicity and genetic diversity within the Fusarium spp. and their variability using peR-based RAPD. A total of 110 isolates comprising five species of Fusarium have been isolated from six sampling areas in Malaysia and one in Brunei Darussalam. The five species identified were F. proliferatum, F. oxysporum, F. solani, F. semitectum and F. /ongipes, based on morphological characteristics. F. proliteretum and F. oxysporum represented the highest percentage (830/0). Pathogenicity tests of F. proiiteretum and F. oxysporum isolates by inoculating healthy asparagus seedlings var. UC157 in the greenhouse confirmed that all isolates tested were pathogenic. The typical symptoms were initially observed as yellowing of leaves and branches. Infected plants were stunted with reddishbrown discoloration and shrivelled roots. Sliced crowns and stems clearly showed reddish-brown discolorations of the infected tissues. Heavily infected plants collapsed and died.
- PublicationPhysiological And Histopathological Analyses Of Silicon Mediated Resistance On Rigidoporus Microporus In Rubber Rootstock Seedlings (Hevea Brasiliensis)(2022-09)White root disease (WRD) is the most severe root disease caused by a soil-borne fungus, mainly Rigidoporus microporus. This pathogen destroys the root system, leading to the death of the rubber tree, Hevea brasiliensis Muell. Arg. The periodical application of chemical fungicides (propiconazole) to control this pathogen has caused environmental pollution issues, hazardous to users, and costly. As an option, the application of silicon integrated fertiliser has proven to be successful in managing diseases on rice, apple, chestnut tree and many else. This study aimed to explore the possibility of using soluble silicon to control the incidence of WRD. The variability study and laccase enzyme production test on nine R. microporus isolates from the culture stock were carried out to select three isolates that showed a significant virulence level. In a pathogenicity test, selected isolates of R. microporus were then inoculated on rubber rootstock seedlings to choose the most virulent isolate. Ayer Molek (AM) isolate was indicated to be the most virulent isolate of R. microporus and had been used in further experiments as a primary source of the pathogen. As an alternative element to propiconazole fungicides, studies had been conducted to determine the effect of different types of soluble silicon (silicic acid, sodium meta-silicate, sodium silicate, and calcium silicate) application on R. microporus growth in both in-vitro and in-vivo study.
- ItemThe Jetty Dwellers Of Penang : Incorporation And Marginalisation Of An Urban Clan Community(Universiti Sains malaysia, 1980-05)This study represents an attempt to analyze at the micro-level the process of socio-economic change in an urban poor community within a metropolitan centre in the Third World. The community chosan — the Chew Jetty settlement in Georgetown, Penang Island, Malaysia - is a waterfront settlement created about a century ago by Chinese migrants sharing a common geographical, historical and lineage origin. Using the world-system approach as a theoretical framework and employing a combination of social research techniques, the study seeks to reconstruct the historical transformation of the jetty community's internal socio-economic structure and the dynamics of its adaptive responses to external changes.
- ItemRepresentation Of Women In Selected Television Dramas Across Different Political Regimes In Pakistan(Universiti Sains Malaysia, 2018-07)Media has a prominent and important role in the representation of different groups, classes and genders in a society. This study aims to examine the representation of women in the television dramas across four different political ruling regimes in Pakistan. The relationship of policies and programs of political ruling governments with the ideology of patriarchy is observed from the representation of women and issues of violation of women’s rights in the television drama. From the Marxist feminist theoretical perspective, the relationship between the hegemony of powerful ruling class and the ideology of patriarchy to the exploitation of a subordinate class of women is examined. The research gap is filled by analysing the representation of women and issues of violation of women’s rights in television dramas across different political regimes in Pakistan which was not explored by previous researchers. The methodological framework is designed using content analysis to examine the representation of women and issues of violation of women’s rights in selected television dramas. The findings of the study revealed that representation of women is neither the reflection of ruling programmes and policies for women nor the real image of women in society. Moreover, the issues of violation of women’s rights are not highlighted through all dramas analysed. However, images of women in television dramas across different political regimes are constructed under the ideology of patriarchy to represent women as a weak and subordinate class in Pakistani society.
- PublicationMicrowave – assisted extraction (mae) of rhizome kaempferia parviflora crude and its biological activity(2021-06-01)Extraction is a process to separate the desired natural products from the raw materials. It has been used in various industry such as food and pharmaceutical industries to achieve certain level of nutrients in the products. However, traditional extraction method required a large volume of solvents and longer extraction time. Hence, advanced extraction which is microwave-assisted extraction was carried out. This research study focusses on green extraction technique where the solvent used is water. Microwave-assisted extraction (MAE) was optimized by Response Surface Methodology (RSM) to enhance the extraction of rhizome K. Parviflora crude. The optimization was done to get the optimum microwave power, microwave extraction time and solvent to feed ratio with maximum response. Central Composite Design (CCD) was selected as a model for RSM to evaluate the first and second-order polynomial model. The analysis of variance was used to evaluate the model fitness and optimal condition. Considering the maximum content of extracted yield, total phenolic content and antioxidant activity, the optimal conditions for all investigated response were obtained at microwave power of 360 W, microwave time of 2 min and solvent feed ratio of (10:1). Under the optimal condition, obtained K. Parviflora crude extract contained 16.72% yield of crude extract, 18.24 μg /ml of total phenolic content and 142.681 μg/ml of antioxidant activity. The study revealed that the response surface methodology (RSM) is an efficient statistical method for preparing appropriate empirical model related to the independent variables and predicting the optimum conditions influencing K. Parviflora crude extract. Microwave-assisted extraction is an environmental-friendly technique for extractions of bioactive compounds and an attractive alternative procedure in industry food and traditional herb.