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Untangling the connection between endocrine disrupting compounds, river pollution classes, and socioeconomic factors
No full textThe contamination of endocrine disrupting compounds (EDCs) stands as an emerging environmental concern, leading to subsequent environmental and human exposure. A comprehensive analysis identified a total of 18 EDCs, including pharmaceuticals, hormones, and plasticizers, in Malaysian rivers classified into distinct pollution classes: “Clean”, “Moderately Polluted”, and “Polluted”. The highest concentration of EDCs was observed in the “Moderately Polluted” Kim Kim River, notably containing 16.25 µg/L of caffeine. Caffeine exhibited ubiquitous presence across all pollution classes, with the Klang River (“Polluted”) showing the peak concentration at 13.62 µg/L. In contrast, the “Clean” Kuantan River displayed the highest EDC concentration at 1.28 µg/L of bisphenol A. All individual EDCs posed negligible ecological risks, with RQ values below 0.01 (RQm < 8.70 × 10⁻3). Similarly, negligible risks were observed for most EDCs under the worst-case scenario (RQex < 2.36 × 10⁻3). Noteworthy findings included the detection of previously undetected pharmaceuticals such as diphenhydramine on a global scale. Variability in the distribution of EDCs among river pollution classes exhibited statistically significant differences in their concentrations. The socioeconomic impact was evident, with gross domestic product (GDP) and population size positively influencing EDC concentrations, emphasizing the interconnected dynamics of urbanization, healthcare development, and pharmaceutical consumption. Additionally, the study identified negligible to low ecological risks associated with both individual and combined exposures to EDCs under general and worst-case scenarios. However, higher EDC risks were observed even in rivers classified as “Clean” or “Moderately Polluted”, highlighting the need for more comprehensive monitoring strategies that account for emerging contaminants
Analytic Hierarchy Progress (AHP) for Construction Technologies Adoption in the Malaysian Construction Industry
Get PDFDigital technologies are vital for boosting productivity and efficiency in Malaysia's construction industry. Despite a 74% awareness rate of Building Information Modeling (BIM) reported in the Malaysia BIM Report 2019, adoption remains limited. This study employs a quantitative methodology, using questionnaire surveys to assess the need for technology adoption among industry players. The findings aim to inform the development of a decision-making tool for selecting suitable technologies for construction projects. By identifying key challenges arising from limited digital adoption, the research proposes strategies to enhance technology integration. Expected outcomes include improved project outcomes, reduced cost overruns, minimized delays, and enhanced industry productivity. Ultimately, these advancements will contribute to Malaysia's GDP growth while addressing critical inefficiencies in the construction sector. Promoting digital adoption is essential for elevating the industry's performance and ensuring its long-term sustainability
Development of A Neuroscreen-1 Cell-Based In Vitro Parkinson’s Disease Model and Discovery of PLT50: Neuroprotective Effects and Molecular Mechanisms
No full textParkinson’s disease (PD) is the second most common neurodegenerative disease and the fastest-growing neurological disorder in the world. To date, no disease-modifying drug is approved clinically for treating PD. The complex pathology of PD remains a challenge in PD drug discovery. Hence, a cellular model of PD that can replicate such pathological features is useful for advancing our understanding of the underlying pathological mechanisms, identifying therapeutic targets, and screening for drug candidates. Phenotypic drug screening using an in vitro cellular model is an important approach in PD drug discovery. As most central nervous system (CNS) drugs come from natural products, this is an important source of potential drugs for PD. This study aimed to develop and optimise an in vitro Neuroscreen-1 (NS-1) cell-based PD model to screen potential compounds from plants and investigate their molecular mechanisms. This in vitro PD model used the neurotoxin 6-hydroxydopamine (6-OHDA) to mimic the pathogenesis of PD. The model's optimisation includes the cell density and cell confluency of NS-1 cells and the concentration of 6-OHDA. Our optimisation experiments showed that 10 µM 6-OHDA is sufficient to induce cell death for screening compounds via cell viability readout as compared to reported concentrations of 20-300 µM of 6-OHDA. PD involves the progressive loss of dopaminergic neurons in the substantia nigra and the accumulation of Lewy bodies, which contains α-syn aggregates. Pathological hallmarks such as dopamine secretion, α-syn expression and neuronal apoptosis were assessed to show the proof of concept of the model. We showed that the model replicated the pathology of PD by showing cells dying from apoptosis and reducing dopamine secretion. Although NS-1 cell line is an effective model for studying dopaminergic neuronal death via apoptosis, it is not a suitable model for α-synucleinopathy. We demonstrated that HEK293T cell line is a suitable cellular model for investigating endogenous α-synucleinopathy as 6-OHDA increased the expression of pathological/phosphorylated α-syn. The model was validated by screening plant-derived neuroprotectants: alpha-mangostin (α-MG), beta-mangostin (β-MG) and gamma-mangostin (γ-MG). With the validated model, we screened compounds from three plants genera: Callophyllum, Uncaria and Aglaia. Screening compounds from the plant genus Callophyllum showed four xanthones - ananixanthone, thwaitesixanthone, brasixanthone B and trapezifolixanthone to be neuroprotective in the in vitro PD model. This is the first report of thwaitesixanthone and brasixanthone B possessing neuroprotective properties. Three compounds (catechin/epicatechin) - EF3, SPB, and SP1 from genus Uncaria also showed neuroprotective activity in PD. A novel compound, PLT50 from genus Aglaia was found to have greatest neuroprotective activity. Therefore, it was selected for further investigation of its neuroprotective mechanisms. PLT50 reduced mitochondrial dysfunction by increasing mitochondrial membrane potential (MMP) and lowering the oxidative stress from 6-OHDA. PLT50 also increased pAKT as a survival signalling pathway for PD. Receptor-mediated mechanisms involving cannabinoid 1 receptor, adenosine A2A receptor, 5-HT1A receptor and CXCR4 receptor were investigated. Results showed that PLT50’s anti-apoptotic effect was abolished when treated with 5-HT1A receptor and CXCR4 receptor antagonist, suggesting the receptors were involved in the protective mechanism. Fluorescent-labelled ligand competitive assay confirmed the binding of PLT50 to the 5-HT1A and CXCR4 receptor. PLT50 is potentially an agonist for the two receptors. In summary, this study established and optimised a cellular PD model using NS-1 cells and provide the first report of HEK293T cells as a model for α-synucleinopathy. Compound PLT50 from genus Aglaia is potentially a PD disease-modifying drug involving two receptors, 5-HT1A and CXCR4
Impact of particulate matter exposure on forced vital capacity and respiratory symptoms in landfill workers
Get PDFIntroduction: Exposure to particulate matter in the workplace has been identified as a major contributing factor to respiratory diseases including decreased lung function. In developing countries, health and safety of landfill workers receives little attention. Thus, it is necessary to conduct an in-depth investigation into particulate matter exposure and its link to disease. This study to investigate the relationship between exposure of Particulate Matter (PM2.5) on forced vital capacity and respiratory symptoms in landfill workers.
Materials and methods: Measurements of PM2.5 parameter air samples were taken using an SNDWAY brand detector from five locations. Interviews using questionnaires with 49 landfill worker respondents were conducted to determine respiratory symptoms. Forced vital capacity was examined with a Voldyne 4000 incentive spirometer and the results were analyzed with chisquare statistical analysis.
Results: The highest PM2.5 concentrations occurred during the day in the west, east, and center, which fall into the unhealthy category. Most of the respondents had abnormal forced vital capacity (32 people, 65.3%) and respiratory symptoms (43 respondents, 87.8%). Chi-square analysis showed a statistically significant association between PM2.5 exposure and abnormal FVC with a p-value of 0.002 and an Odds Ratio (OR) of 10.0 (95% CI: 2.41–41.58).
Conclusion: This study found a significant association between PM2.5 exposure and abnormal Forced Vital Capacity (FVC) in landfill workers (p = 0.002; OR= 10.0; 95% CI: 2.41–41.58). These findings indicate that workers exposed toPM2.5 are at increased risk of lung function impairment, underscoring the need for routine respiratory health monitoring and targeted exposure mitigation in landfill environments
Gut and skin microbial profiling of healthy and dropsy diseased Malaysian Mahseer Empurau (Tor tambroides) following exposure to antimicrobial agents
Get PDFAims: The study was aimed to identify bacterial pathogens from dropsy diseased Tor tambroides, compare the isolated
bacteria from dropsy and healthy Empurau and assess their sensitivity towards various antibiotics. Methodology and results: To identify the possible causative agents of dropsy in diseased fish, we conducted pure culture of bacteria using spread plate techniques, Gram’s staining, KOH string test, 16S rRNA gene sequencing and antibiotics susceptibility test. Plate and microscopic observation revealed that most bacterial strains from healthy and
dropsy diseased Empurau are Gram-negative, KOH reaction-positive and rod-shaped. The characterization of 16S rDNA
sequence revealed that most of the bacteria were Pseudomonas spp., with a higher number identified in dropsy-affected
Empurau than healthy ones. It is postulated that P. fluorescens, Aeromonas spp., Citrobacter freundii and P. congelans are the major causative agents of dropsy disease in Empurau fishes, but further investigations are required to strengthen this claim. Antibiotic susceptibility tests uncovered two multi-drug resistant bacterial strains (resistant to at least three antibiotics) from the gut and skin of healthy Empurau fish, respectively. Interestingly, all dropsy diseased Empurau gut isolates were susceptible to Morepenem and Tetracyclin, whereas all dropsy diseased Empurau skin isolates were susceptible to Chloramphenicol.
Conclusion, significance and impact of study: The data on the possible causative agents of dropsy disease in Empurau fishes will be beneficial in managing fish bacterial diseases. The local aquaculture yield can be further
improved through future research and elucidation on the biochemical characterization and disease management of bred
Empurau fish
Assessment for learning practices among Malay language teachers in Malaysia National Type Chinese School
Get PDFThis study investigates the issues Malay language teachers in Malaysia National Types Chinese School (SJKC) regarding the inconsistent application assessment for learning (AfL) practices, the persistence of traditional teacher-
centered, and the challenge of aligning AfL practices with curriculum standards and assessment criteria. These issues have a critical impact on the effectiveness of assessment, teaching, and learning. Given AfL’s potential to address educational challenges and enhance student outcomes, this study is highly relevant. To achieve this goal, a qualitative case study design approach, six participants were selected using the following criteria in purposive
sampling, using data gathered from in-depth semi-structured interviews, informal conversations, lesson plans and assessment methods. Thematic analysis conducted using Atlas.ti, revealed three main themes: knowledge of
AfL, AfL practice, and obstacles and challenges. The results show that most teachers primarily use belief AfL to improve student outcomes, but there are significant differences between beliefs and practices. Moreover, lack of
knowledge which poses challenges due to shifts in curriculum standards and assessment administration in school. Given the results, suggestions embedding AfL principle into AfL practices to develop an objective framework for AfL and tracking second language learners’ language proficiency and progress, improving learning outcomes and language
acquisition
Pemodelan Ruang dan Masa Kes Jenayah Harta Benda dan Kekerasan di Wilayah Persekutuan Kuala Lumpur dan Wilayah Persekutuan Putrajaya
Get PDFPenyelidikan ini menganalisis data jenayah harta benda dan jenayah kekerasan sepanjang tempoh enam tahun, dari tahun 2015 hingga tahun 2020. Ia meliputi bidang kuasa Ibu Pejabat Polis Kontinjen Kuala Lumpur (IPPKKL) yang meliputi Wilayah Persekutuan Kuala Lumpur (WPKL) dan Wilayah Persekutuan Putrajaya (WPP). Kajian ini menggunakan teknologi Sistem Maklumat Geografi (GIS) untuk mengenal pasti jenayah melalui rekod yang terperinci mencakupi kanun keseksaan, lokasi dan masa kejadian. Ia mendedahkan taburan ruang dan masa kejadian jenayah, mengenal pasti hotspots serta memodelkan hubungan antara jenayah dengan faktor guna tanah dan demografi. Permasalahan kajian ini terbahagi kepada tiga iaitu (i). Dinamika kes jenayah harta benda dan kekerasan; (ii). Kes jenayah harta benda dan kekerasan dalam konteks ruang-masa; dan (iii). Hubungan antara faktor demografi dan guna tanah dengan kes jenayah harta benda dan kekerasan. Objektif Kajian pula terbahagi kepada tiga iaitu (i). Mengenal pasti arah aliran dan taburan ruangan kes jenayah harta benda dan kekerasan di kawasan kajian. (ii). Menganalisis variasi corak pengelompokan kes jenayah harta benda dan kekerasan dari segi ruang dan ruang-masa di kawasan kajian berdasarkan guna tanah terlibat. dan (iii). Memodelkan hubungan faktor demografi dan guna tanah dengan kes jenayah harta benda dan kekerasan di kawasan kajian. Kaedah analisis yang digunakan di dalam kajian ini ialah Analisis Deskriptif, Spatial Autocorrelation (Global Moran's I Index), Emerging Hot Spot Analysis (EHSA), Mean Center (MC), Standard Deviational Ellipse (SDE) dan Linear Regression (LR). Analisis mendedahkan Spatial Autocorrelation yang ketara dalam kejadian jenayah harta benda, terutamanya pada tahun 2016, yang menunjukkan corak pengelompokan. Sebaliknya, jenayah kekerasan menunjukkan taburan yang lebih kompleks dengan pengelompokan yang ketara hanya diperhatikan pada tahun 2018. Analisis EHSA dengan jenayah harta benda dan kekerasan menunjukkan guna tanah pengangkutan dan jalan dan perumahan dan kediaman menunjukkan nilai yang paling signifikan. Regresi linear menunjukkan faktor guna tanah pengangkutan dan jalan dan kediaman dan perumahan mempunyai korelasi yang kuat untuk jenayah harta benda manakala jenayah kekerasan mempunyai korelasi yang kuat dengan guna tanah industri dan badan air. Faktor demografi pula menunjukkan populasi lelaki dan populasi perempuan mempunyai korelasi yang kuat dengan jenayah harta benda dan kekerasan. Penemuan ini menekankan sifat dinamik corak jenayah, dipengaruhi oleh pembangunan bandar, jumlah penduduk dan jurang sosioekonomi. Implikasi kajian terbahagi kepada lima iaitu (i). peningkatan keberkesanan strategi kawasan panas (hotspots policing), (ii). perancangan guna tanah yang lebih strategik, (iii). pengurusan demografi dalam kawasan berisiko, (iv). kesan sosioekonomi dan kesejahteraan komuniti dan (v). pemantauan dan penilaian berasaskan data untuk dasar pencegahan jenayah. Kesimpulanya, kajian ini mendapati bahawa jenayah harta benda dan kekerasan di Kuala Lumpur dan Putrajaya menunjukkan pola taburan ruang-masa yang berbeza, dipengaruhi oleh faktor guna tanah dan demografi. Penggunaan GIS menunjukkan hubungan kuat antara jenayah harta benda dengan guna tanah pengangkutan dan kediaman, manakala jenayah kekerasan lebih berkait dengan guna tanah industri dan badan air. Hasil ini menekankan pentingnya strategi pencegahan jenayah yang berasaskan data serta perancangan guna tanah dan pengurusan populasi yang lebih strategik di kawasan berisiko tinggi
Low variations in anatomical characters of lowland and upland rice from Sarawak, Malaysian Borneo
Get PDFOryza sativa L. or commonly known as rice belongs to the family of Poaceae. In Malaysia, rice is normally cultivated
either as lowland or upland rice. The present study was undertaken with the objective to characterise and document the variations in anatomical traits of leaf, midrib and the root of 22 lowland and 22 upland rice accessions. The leaf, midrib and root anatomy of the lowland and upland rice accessions have the same fundamental anatomical structure. Stomata were found abundant on the abaxial surface as compared to the adaxial surface in general. It is interesting to note that the upland rice accessions, in general, had higher stomatal density on the adaxial surface. In addition, the upland rice accessions, in general, had larger root and stele diameters as compared to lowland rice accessions. The variation in root diameter is associated to the changes in the number and size or width of cortical cells and stele diameter. Wider stele may allow higher plant water status under water deficit, due to higher hydraulic conductivity. In addition, greater xylem diameter (indicated by larger stele diameters) is linked to better axial conductance, which improved rice’s ability to absorb
and hold more water during water-limiting conditions. These traits are possibly advantageous for upland rice for efficient water capture, especially under water-deficit stress
Factors Affecting Student Academic Performance : A Systematic Review
Get PDFThis systematic review synthesizes evidence on factors affecting Student Academic Performance (SAP), focusing on individual, family, school, and social dimensions. A comprehensive search using Google Scholar covered studies from 2000 to July 2024. Thematic synthesis revealed that individual factors such as age, gender, motivation, self-efficacy, and test anxiety significantly impact SAP. Family influences, including parents’ education, income, and involvement, were also crucial. School-related factors like teachers’ qualifications, self-efficacy, and teaching methods emerged as important, while social factors such as peer relationships, social support, private tutoring, and socioeconomic status also played key roles. However, inconsistencies were found in the magnitude and direction of some effects, indicating the need for further exploration of these influences. The educational relevance and implications of this research are significant, as it highlights a comprehensive understanding of the factors influencing SAP across multiple dimensions—individual, family, school, and social. Practically, this research provides crucial insights for educators, policymakers, and stakeholders to implement targeted interventions that foster supportive learning environments, ultimately enhancing student outcomes