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Rapid urbanization will cause various land use changes and the vast occupation of green spaces, a critical factor in the deterioration of biodiversity in urbanized areas. Some species of wildlife are endangered due to habitat shrunk and fragmentation. However, Malaysia's current biodiversity protection range is still limited. The Ecological Network (EN) refers to a framework of ecological components, which can be obtained by geographical and technical approaches to support more ecological diversity ranges. Furthermore, little research has been found on EN in Malaysia and the impact of land use change on EN. Therefore, the Selangor region is selected as the study area. This paper quantifies land use change and measures the extent of land use change to obtain the EN's change. The result has shown that forestland has decreased, explored by people for housing and agriculture from 2000 to 2020. The EN has a trend of fragmentation. Overall, this study's results imply that the land use change led to EN's worsened performance from 2000 to 2020 in the study area. This paper hopes that this research could help supply information on conserving biodiversity in future development and urban sustainable planning in Malaysia. [ABSTRACT FROM AUTHOR]

This paper aims to develop a measurement of spiritual poverty for an urban residents based on the spiritual concept and practice of purifying of the self (Tazkiyah Al-Nafs). This follows the process of cleansing of the self, where the nature of bad practices are replaced with those of good practices. A quantitative approach was utilised by distributing questionnaires to 528 urban Muslim households in Kuala Lumpur, Selangor and Putrajaya, Malaysia, which was then analysed using descriptive analysis. This was, then, followed by the usability assessments by 14 experts from academia and industry, where the data was analysed using the 'fuzzy delphi method'. Findings indicated that 27.84% of respondents experienced spiritual poverty relating to the emotional indicator, 17.42% experienced from a perceptual indicator, while 91.86% of respondents experienced poverty from a practices indicator perspective. The study points out that the elements of emotion, perception and practice as indicators holds significance in measuring spiritual poverty with a percentage expert consensus of 78.6% on emotion and perception indicators and 85.7% on practices indicator. The results gives credence to the expansion of the concept of multidimensional poverty, to include measuring psycho-spiritual deprivations as one component of poverty in addition to measuring both monetary and non-monetary factors as currently being advocated. This study calls for further exploration of this important area relating to self development, which has been overlooked in poverty measurements. [ABSTRACT FROM AUTHOR]

The present paper discussed the comparison of the persistence and mobility of metsulfuron-methyl from a residue field trial experiment and simulation using a VARLEACH model. The residue field trial experiment was performed at Sungai Buloh Oil Palm Estate, Selangor. The plots were treated with metsulfuron-methyl at two treatment rates of 15 g a.i ha−1 (T1) and 30 g a.i ha−1 (T2). Soil samples were collected at 0, 1, 3, 7, 14, 21, 30, 60 and 90 days after treatment (DAT) and analysed subsequently by HPLC–UV. The results show that metsulfuron-methyl degraded rapidly in the soil with the half-life (t½) of 6.3 days in T1 and 7.9 days in T2. The simulation of VARLEACH model gave similar pattern of persistence and mobility of metsulfuron-methyl in the soil profile. However, total residues and the mobility of the metsulfuron-methyl were poorly simulated by the VARLEACH model due to consistent overestimation of the quantified residues. Results indicated that the metsulfuron-methyl lost more rapidly than the prediction values from VARLEACH model. In this case, simulation models which use transformation routines similar and which include additional degraded processes such as leaching, volatilisation, plant uptake or runoff could be considered. Albeit, overestimated values on the concentrations of metsulfuron-methyl are reported using VARLEACH model, the model still can be used as rapid and fast approach to predict the behaviour of pesticide at minimum cost. [ABSTRACT FROM AUTHOR]

Eco-friendly raft-pile foundation (ERP) system is one of the most recent developed types of pile foundations that the original materials can be provided from local Bakau. A precise prediction of its behaviour is of interest for many engineers. This paper presents three intelligent systems, namely, adaptive neuro-fuzzy inference system (ANFIS), conventional artificial neural network (ANN), and optimized ANN model with genetic algorithm (GA) for prediction of vertical settlement in ERP system. In this regard, a database compiled from 43 load-settlement results obtained from full-scale maintained load test (PLT). Note that, these floating raft-pile system piles were subjected to vertical axial loading. The ERP system was installed at the marine soft clay soil site at Rantau Panjang Kapar, Selangor, Malaysia. The values of subgrade modulus (Ks), Young's modulus (Es), soil properties beneath the footing, and applied load were set as model input to predict vertical settlement (s). To evaluate the reliability of the network output, several well-known statistical indexes were used. The results show that the new proposed GA-ANN model could provide a better performance in estimating the maximum settlement of ERP system. In terms of statistical indexes (R2, and RMSE), the values of (0.998, 0.0259, and 99.99) and (0.997, 0.0324, and 99.998) were obtained for both data sets of training and testing, respectively. Besides, comparing the training and testing data sets, R2 values of (0.994, 0.9884, 0.995, and 0.9984) and (0.996, 0.985, 0.994, and 0.9973) were found for ANN–LMBP, ANFIS, GA, and GA-ANN models, respectively, which proves the superiority of the proposed GA-ANN model comparing to other methods. [ABSTRACT FROM AUTHOR]

The strength characteristics of a rock is a criterion for its ability to be drilled and fractured. The uniaxial compressive strength (UCS) is the most commonly used strength index in construction industry and in rock engineering projects. Therefore, a comprehensive knowledge on the factors that could influence the value of the compressive strength is essential in any rock engineering project. This paper explores the effects of mineralogical composition on the UCS value of granitic rocks to evaluate its drillability. Samples of granitic rocks were collected from the Interstate Raw Water Transfer Tunnel project. The rock samples were characterized with quantitative Rietveld XRD method to quantify the relative mineral phase compositions in the rock samples. The relationships between mineralogical properties and UCS were investigated by simple regression analysis. The strength of the rock samples increases with higher composition of quartz and decreases with increase in the composition of feldspar and kaolinite. The positive effects of quartz on the strength of the granitic rock is more significant than the negative influence of feldspar and clay content. The drilling rate varies inversely with the UCS. [ABSTRACT FROM AUTHOR]

Although pharmaceuticals treat illnesses and prevent diseases in humans and animals, ironically, they are now among the emerging pollutants in the environment. As individuals continue to consume medicines, households can become a primary source of pharmaceutical pollutants. This paper explains relevant Malaysian law and policy on the issue. Using a questionnaire survey, it also assesses public perception concerning the environmental impact of pharmaceutical waste and the current methods of disposal that are practiced in Selangor. The survey used a convenience sampling and the data collected were analysed using statistical descriptive analysis. Most of the participants were aware that pharmaceutical waste can have an adverse impact on the environment and public health. Half of the participants disposed of their pharmaceutical waste in trash bins. About 2.9% of the respondents poured their household pharmaceutical waste (HPW) directly down the drain, while 8.8% poured them down the sink in the kitchen or toilet. The study also discovered that while 73.8% of the respondents felt that HPW should be separated from other household solid waste, only 25.2% returned their medicinal waste through the medicine return-back programme. The majority of the respondents (82.5%) agreed that information concerning the proper disposal of HPW is insufficient. The study concludes that while the respondents were aware of the adverse impact of HPW, their practices to ensure proper disposal is discouraging. There is a need for effective unwanted medicines return-back programme as a more prudent disposal method of HPW to avoid any risk to the environment or human health. [ABSTRACT FROM AUTHOR]

Rapid infrastructure development in Malaysia especially in Selangor causes drastic change in landscape and clearing of more vegetated areas. This has gradually lead to slope instability problems that causes enormous loss affecting human lives, destruction of property and environment. Thus, conservation practices by incorporating vegetation to enhance slope stability is much needed alternative to the conventional technique of stabilization. Limited studies had been done in discovering the effectiveness of vegetative covers in relation to slope and soil parameters. Hence, in this paper, a parametric study is carried out to discover the relationship between some of the various vegetation species and different soil types as well as slope angles. Conventional limit equilibrium methods are applied in the analysis considering the soil shear strength parameters, unit weight of soil, as well as slope geometry. Typical scenarios of cut-slope along highways in Selangor are simulated in order to obtain comparable results from the stability assessment by means of calculating the factor of safety. The modelling showed that shallow slip failure can be prevented when sufficient number of roots of a certain tensile force interact with the slip plane, increasing the overall factor of safety of the slope. The percentage of FOS increased due to the vegetation effects can reach up to 43% with slope angles ranging between 15° and 25°. Moreover, based on the parametric study, silty soils showed more significance in contributing to the increase in FOS when incorporating vegetation. [ABSTRACT FROM AUTHOR]

This study examines the state of migrants' cultural adaptation in Malaysia, and how such an adaptation can help build our understanding of migrants' life and employment experiences in the country. In doing so, this study has adopted a quantitative approach, with a completed survey towards 410 migrant respondents, living and working temporarily in Selangor, Malaysia. A multiple regression analysis finds that the three most significant predictors contributing to the respondents' cultural adaptation are "positive experiences" (β =.677, p =.000), "closeness" (β = −.107, p =.008), and "social relationships" (β =.095, p =.032). While "positive experiences" and "social relationships" influence the migrant workers' adaptation positively, the "closeness" predictor on the contrary (negative). Another predictor, "disconnection", is found to be not statistically significant. The one-way analysis of variance (ANOVA) reveals significant differences in the respondents' cultural adaptation based on such demographic characteristics as age, gender, level of education, nationality, length of employment, and sector of employment. For instance, female migrants are strongly associated with a higher level of "positive experiences" [F(1, 408) = 6.321, p =.013] and "social relationships" [F(1, 408) = 5.634, p =.018], while male migrants tend to rely on cultural proximity (i.e., "closeness") [F(1, 408) = 6.828, p =.009]. The discussion section highlights attributes such as the gender factor in cultural adaptation, preservation of cultural identities, and creation of migrants' symbolic places to understand how cultural adaptation intersects with the migrant workers' daily lives and experiences. This study concludes that as Malaysia's economy continues to rely on migrant workers, it needs to better understand the workers' cultural adaptation and their far-reaching impact on their life experiences and employment conditions in the country. [ABSTRACT FROM AUTHOR]

After withdrawing the movement control order (MCO), new variant (Omicron) of COVID-19 returns as an outbreak again. Therefore, consumers are very much informed by various media to be more cautious in visiting shopping malls and spend less time in there. The purpose of this study was to identify the predictors influencing the desire to stay shorter at the shopping mall. This study was conducted in Malaysia, with the application of three psychological theories and one behavioural theory. This is quantitative research based on an online cross-sectional survey design. Data were collected from 296 respondents, by applying the online snowball sampling method through numerous media platforms i.e., Viber, WhatsApp, Messenger, and other apps in three severely affected cities in Malaysia i.e., Selangor state, Putrajaya, and Kuala Lumpur. SmartPLS was used to analyse the data. Using structural equation modelling, this study result shows risk, protection motivation, and fear have a significant effect on the desire to stay a shorter time at the shopping mall. Social norm moderates the association between fear and the desire to spend a shorter time at the shopping mall. These findings, highlight the need for a more empirical study to design more robust strategies, and a safer and risk-free shopping mall environment. [ABSTRACT FROM AUTHOR]

Background: Urban heat island (UHI) is an urban climate phenomenon that primarily responds to urban conditions and land use change. The extent of hard surfaces significantly influences the thermal properties of the land. To address this issue, a novel approach quantifying the association between land use and UHI is developed. This study offers a new technique for effectively estimating the effect of land use on the UHI intensity using the combination of urban heat intensity index (UHII) and land contribution index (LCI) derived from Landsat 8 OLI images. The time-series thermal effect of land use on the UHI intensity can be determined according to the ratio in mean temperature between specific land use and the whole study site. The study was conducted in the Hulu Langat district, Malaysia during 2014–2021. Results: The UHI intensity rose from 0.19 in 2014 to 0.70 in 2021. The negative value of LCI for vegetation areas and water bodies obtained its negative contribution to the urban heat island, while the positive value of LCI for bare areas and built-up areas showed its positive effect on the urban heat island. The LCI value for urban areas showed a significant increase in the 7 years such as 0.51, 0.66, 0.69, and 0.75 for periods 2014, 2016, 2018, and 2021, respectively. The change in LCI from 2014 to 2021 for the transformation of bare area and forest was recorded to be 0.23 and − 0.02, respectively. Thus, the conversion of forests into urban areas had a negative effect on the increment of UHI intensity. Conclusions: Overall, these findings are useful for policy-making agency in developing an effective policy for reducing high UHI intensity and planning long-term land use management. [ABSTRACT FROM AUTHOR]

Microplastic pollution has received growing interest due to its persistence and detrimental effects on humans and aquatic organisms. While microplastics in marine sediment have received a lot of attention, microplastics in riverine sediment, particularly in river basins, remain scarce. Therefore, sediment sample was collected from 25 sampling points along the Selangor River Basin and its urbanized tributaries. Microplastics were observed and identified using stereomicroscope and Fourier transform infrared spectroscopy with attenuated total reflection (FTIR-ATR). The results indicated that microplastics were present in all sediment samples, with concentrations ranging from 10 to 55 particles/kg. Small microplastics (< 300 μm) dominated more than half of all microplastics observed, with black color and bead-shaped being the most common characteristic. Polypropylene, polyester, and polyethylene were the primary polymer compositions of the microplastics. The findings suggest that anthropogenic activities from residential, agricultural, and industrial sources may contribute to the ubiquity of microplastics in river. These results highlight the need for further monitoring assessment and proactive measures to mitigate microplastic pollution in riverine environments. [ABSTRACT FROM AUTHOR]

Information on the relations between phytoplankton communities and the environment is limited for the man-made lakes in Malaysia. This paper presents the results of a study on the diversity and seasonal succession of phytoplankton in Seri Serdang Lake and Faculty of Engineering Lake conducted between November 2013 and February 2014. A total of 27 species from four phyla (Chlorophyta, Euglenophyta, Cyanobacteria, Bacillariophyta) and 33 species belonging to Cyanobacteria, Chlorophyta, Bacillariophyta, Euglenophyta and Dinophyta were identified from Seri Serdang Lake and the Faculty of Engineering Lake, respectively. Chlorophyta were most dominant in both lakes. Highest number of species recorded was Monoraphidium sp. in Seri Serdang Lake and Pediastrum tetras in Faculty of Engineering Lake. Seri Serdang Lake had lower phytoplankton density (20 cells ml-1 to 396 cells ml-1) as compared to the Faculty of Engineering Lake (250 cells ml-1 to 300 cells ml-1). Although the distance between the two lakes is short, they do not share the same tributary probably leading to the observed differences in water quality, species diversity and succession pattern. [ABSTRACT FROM AUTHOR]

Rapid urbanization has caused severe deterioration of air quality globally, leading to increased hospitalization and premature deaths. Therefore, accurate prediction of air quality is crucial for mitigation planning to support urban sustainability and resilience. Although some studies have predicted air pollutants such as particulate matter (PM) using machine learning algorithms (MLAs), there is a paucity of studies on spatial hazard assessment with respect to the air quality index (AQI). Incorporating PM in AQI studies is crucial because of its easily inhalable micro-size which has adverse impacts on ecology, environment, and human health. Accurate and timely prediction of the air quality index can ensure adequate intervention to aid air quality management. Therefore, this study undertakes a spatial hazard assessment of the air quality index using particulate matter with a diameter of 10 μm or lesser (PM10) in Selangor, Malaysia, by developing four machine learning models: eXtreme Gradient Boosting (XGBoost), random forest (RF), K-nearest neighbour (KNN), and Naive Bayes (NB). Spatially processed data such as NDVI, SAVI, BU, LST, Ws, slope, elevation, and road density was used for the modelling. The model was trained with 70% of the dataset, while 30% was used for cross-validation. Results showed that XGBoost has the highest overall accuracy and precision of 0.989 and 0.995, followed by random forest (0.989, 0.993), K-nearest neighbour (0.987, 0.984), and Naive Bayes (0.917, 0.922), respectively. The spatial air quality maps were generated by integrating the geographical information system (GIS) with the four MLAs, which correlated with Malaysia's air pollution index. The maps indicate that air quality in Selangor is satisfactory and posed no threats to health. Nevertheless, the two algorithms with the best performance (XGBoost and RF) indicate that a high percentage of the air quality is moderate. The study concludes that successful air pollution management policies such as green infrastructure practice, improvement of energy efficiency, and restrictions on heavy-duty vehicles can be adopted in Selangor and other Southeast Asian cities to prevent deterioration of air quality in the future. [ABSTRACT FROM AUTHOR]

Toxic cyanobacteria blooms are increasing in magnitude and frequency worldwide. However, this issue has not been adequately addressed in Malaysia. Therefore, this study aims to better understand eutrophication levels, cyanobacteria diversity, and microcystin concentrations in ten Malaysian freshwater lakes. The results revealed that most lakes were eutrophic, with total phosphorus and total chlorophyll- a concentrations ranging from 15 to 4270 µg L and 1.1 to 903.1 µg L, respectively. Cyanobacteria were detected in all lakes, and identified as Microcystis spp., Planktothrix spp., Phormidium spp., Oscillatoria spp., and Lyngbya spp. Microcystis spp. was the most commonly observed and most abundant cyanobacteria recorded. Semi-quantitative microcystin analysis indicated the presence of microcystin in all lakes. These findings illustrate the potential health risk of cyanobacteria in Malaysia freshwater lakes, thus magnifying the importance of cyanobacteria monitoring and management in Malaysian waterways. [ABSTRACT FROM AUTHOR]

Although there are numerous works on how well-being in old age can be influenced by the built environment, little research has been conducted in Malaysia. In this study, we hypothesized that the characteristics of the residential environment would have a positive impact on the life satisfaction of older adults in Malaysia. Third places are recognized as an important factor in improving the quality of life of older adults, enabling them to age in place. However, there is still much to be explored on the types of third places in the neighborhood that are critical in promoting the well-being of older adults. To address this gap, this study also examined which third places older adults in Malaysia commonly frequent and which types of third places are associated with life satisfaction. A convergent parallel mixed-method approach was used, which included a survey with a sample of 250 older adults aged 60 years and older living in Bandar Sunway in the state of Selangor in Malaysia, and an in-depth interview with respondents. The findings highlight the role of residential environment characteristics and third places ─ particularly shopping, culture, and education-related places—on the life satisfaction of older people in Malaysia. By demonstrating the environmental determinants of older people's well-being in Malaysia, this study provides urban planners and housing associations with information for creating age-friendly communities. [ABSTRACT FROM AUTHOR]

This study investigates whether there exist personality differences between consumers of videogames and non-consumers of videogames. This is explored through the HEXACO model, which derives HEXACO scores indicative of a particular personality profile. The model assesses the dimensions of honesty-humility, emotionality, extraversion, agreeableness, conscientiousness, and openness to experience. The investigation utilized a causal-comparative approach to examine personality differences. A sample of 855 teenage students attending private and public institutions in the Perak and Selangor states of Malaysia participated in the study. The sample contained 475 non-videogame consumers and 380 videogame consumers. The study revealed that videogame consumers have a personality profile that is significantly different on agreeableness, extraversion, conscientiousness, and openness to experience compared to non-videogame consumers. Our study is first to utilize the HEXACO model to evaluate personality differences between videogame consumers and non-videogame consumers. [ABSTRACT FROM AUTHOR]

Dengue is a mosquito-borne disease that causes high mortality and fatality rate among humans. The disease and the virus are spread through female Ae. aegypti and Ae. albopictus. 176 Modified Sticky Ovitraps (MSO) were installed in six blocks of high-rise apartment buildings in Petaling Jaya, Selangor. The specimens were collected throughout a duration of 26 weeks. NS1 dengue antigen kit was used to detect dengue antigen in mosquitoes, and positive mosquitoes were serotyped using Reverse Transcriptase-PCR, followed by Multiplex-PCR. The relationship between the number of Aedes mosquitoes and meteorological parameters was also determined. The association between the number of Aedes spp. captured, dengue cases, and positive specimens was also evaluated in this study. A total of 243 adult mosquitoes were successfully captured using MSO, with 95.1% (231) of the mosquitoes being Ae. aegypti, while 4.1% (10) and 0.8% (2) were Ae. albopictus and a mixed Aedes species, respectively. The molecular detection of the dengue virus showed that only 2 individual specimens of Ae. aegypti were positive, with one specimen being a dual serotype of DEN-II and IV, and another specimen was DENV-II. The weekly number of Aedes spp. captured correlated positively with Tmax, Tmin, and Tmean, and correlated negatively with RF and RH. The significant and useful data obtained from this study can be utilized in dengue vector management by local health authorities. [ABSTRACT FROM AUTHOR]

Home ownership is one key factor of the principles of livability towards achieving liveable city. In addition, there are also many factors affecting home ownership which includes income, location and accessibility factor. Various issues have been discussed by the Government of Malaysia in addressing the concern of home ownership, especially for the middle- and low-income groups in many cities in Malaysia. Using the case of Kajang city, this article aims to achieve the objective of identifying the major factors affecting home ownership for liveable city focusing the middle-income earners. Purposive sampling was used and in-depth interviews method were conducted with 41 potential homebuyer, 60 homeowners and 20 housing experts representing the Federal Government agencies, State Government agencies, Municipal Government, Developers, Banks and Real Estate-Related Consultant. The result of the study shows that the main factors affecting home ownership are income, housing loan scheme, location, government role, developer role, PR1MA affordable housing scheme, construction cost, Bumiputera quotas, lifestyle, quality of life, real estate investment and transfer, assessment/property tax, land ownership by foreigners and ownership title. The findings show that the Kajang City is an example of a city that can contribute to the affordable housing strategy requirements towards achieving liveable city. The findings also will help key stakeholder in addressing the main issues of housing affordability in the State of Selangor. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic first emerged in Malaysia in Jan 2020. As of 12th Sept 2021, 1,979,698 COVID-19 cases that occurred over three major epidemic waves were confirmed. The virus contributing to the three epidemic waves has not been well-studied. We sequenced the genome of 22 SARS-CoV-2 strains detected in Malaysia during the second and the ongoing third wave of the COVID-19 epidemic. Detailed phylogenetic and genetic variation analyses of the SARS-CoV-2 isolate genomes were performed using these newly determined sequences and all other available sequences. Results from the analyses suggested multiple independent introductions of SARS-CoV-2 into Malaysia. A new B.1.524(G) lineage with S-D614G mutation was detected in Sabah, East Malaysia and Selangor, Peninsular Malaysia on 7th October 2020 and 14th October 2020, respectively. This new B.1.524(G) group was not the direct descendant of any of the previously detected lineages. The new B.1.524(G) carried a set of genetic variations, including A701V (position variant frequency = 0.0007) in Spike protein and a novel G114T mutation at the 5'UTR. The biological importance of the specific mutations remained unknown. The sequential appearance of the mutations, however, suggests that the spread of the new B.1.524(G) lineages likely begun in Sabah and then spread to Selangor. The findings presented here support the importance of SARS-CoV-2 full genome sequencing as a tool to establish an epidemiological link between cases or clusters of COVID-19 worldwide. [ABSTRACT FROM AUTHOR]

The heavy metals namely Fe, As, Cu, Cd, and Pb were investigated in two marine fishes silver pomfret (Pampus argentus) and torpedo scad (Megalaspis cordyla), and three seafoods sibogae squid (Loligo sibogae), Indian white prawn (Fenneropenaeus indicus), and mud crab (Scylla serrata) by using inductively coupled plasma spectrophotometer (ICP-MS) from two renowned fish harvesting coastal area of Malaysia named as Kedah and Selangor. Among the target heavy metals, highest mean concentration of As and Fe were found in Scylla serrata (72.14±7.77 μg/g) in Kedah and Megalaspis cordyla (149.40±2.15 μg/g) in Selangor. Pearson's correlation results showed As-Fe-Cd-Cu originated from the same source. Maximum estimated daily intake (EDI) values of Scylla serrata were found 175.25 μg/g/day and 100.81 μg/g/day for child in both Kedah and Selangor areas respectively. Hazard quotient (HQ) and hazard index (HI) results revealed that local consumers of Kedah and Selangor will face high chronic risk if they consume Scylla serrata, Fenneropenaeus indicus, and Megalaspis cordyla on regular basis in their diet. Carcinogenic risk results suggested that all the studied species pose very high risk of cancer occurrences to the consumers in both areas. Therefore, it could be recommended that consumers should be aware when they are consuming these marine species since they can pose serious health risk associated with prolonged consumption. [ABSTRACT FROM AUTHOR]

This study proposes a novel design to systematically optimize the parameters for the adaptive neuro-fuzzy inference system (ANFIS) model using stochastic fractal search (SFS) algorithm. To affirm the efficiency of the proposed SFS-ANFIS model, the predicting results were compared with ANFIS and three hybrid methodologies based on ANFIS combined with genetic algorithm (GA), differential evolution (DE), and particle swarm optimization (PSO). Accurate prediction of uniaxial compressive strength (UCS) is of great significance for all geotechnical projects such as tunnels and dams. Hence, this study proposes the use of SFS-ANFIS, GA-ANFIS, DE-ANFIS, PSO-ANFIS, and ANFIS models to predict UCS. In this regard, the fresh water tunnel of Pahang–Selangor located in Malaysia was considered and the requirement data samples were collected. Different statistical metrics such as coefficient of determination (R2) and mean absolute error were used to evaluate the models. Referring to the efficiency results of SFS-ANFIS, it can be found that the SFS-ANFIS (with the R2 of 0.981) has higher ability than PSO-ANFIS, DE-ANFIS, GA-ANFIS, and ANFIS models in predicting the UCS. [ABSTRACT FROM AUTHOR]

Microplastics have been considered as contaminants of emerging concern due to ubiquity in the environment; however, the occurrence of microplastics in river estuaries is scarcely investigated. The Klang River estuary is an important ecosystem that receives various contaminants from urbanised, highly populated areas and the busiest maritime centre in Selangor, Malaysia. This study investigates the abundance and characteristics of microplastics in surface water of the Klang River estuary. The abundance of microplastics ranged from 0.5 to 4.5 particles L–1 with a mean abundance of 2.47 particles L–1. There is no correlation between the abundance of microplastics and physicochemical properties, while there is a strong correlation between salinity and conductivity. The microplastics were characterised with a stereomicroscope and attenuated total reflection–Fourier transform infrared spectroscopy to analyse size, shape, colour, and polymer composition. The microplastics in the surface water were predominantly in the 300–1000 μm size class, followed by > 1000 μm and < 300 μm, and were mostly transparent fibres, fragments, and pellets. Polyamide and polyethylene were the main polymer types in the composition of the microplastics, suggesting that the microplastics originated from heavily urbanised and industrial locations such as the port, jetty, and residential areas. The widespread occurrence of microplastics in the environment and subsequent penetration of aquatic food webs may pose a serious threat to organisms. This study provides baseline data and a framework for further investigation of microplastic contamination in estuaries. [ABSTRACT FROM AUTHOR]

Background: Indoor air quality (IAQ) is a concern in kindergartens as children spend much of their time there. Yet, there is a shortage of biological indicators needed for assessing IAQ. Thus, this study evaluated IAQ using transplanted lichen Usnea misaminensis as a biological indicator. Methods: Lichen samples, collected from Bukit Larut, Perak, Malaysia, were exposed to indoor and outdoor environments in an urban area (Ummi Aiman Kindergarten) and a rural area (Ummi Qaseh Pelangi Kindergarten) for 2 months during August 15 to October 14, 2019. The concentrations of 12 selected elements and the vitality of the lichens were then evaluated. Results: Increased concentrations of eleven of the twelve elements deposited in the lichen samples in both urban and rural areas were observed. For both areas, the element concentrations in the samples from the indoor environment was lower than those from the outdoor environment, and those in the rural area were lower than those from in the urban area, suggesting the impacts of traffic emissions. The vitality of the lichens showed no significant change in indoor environment, compared to that in outdoor environment, indicating that even exposed to indoor environment, the lichens remained effective biological indicators as same as they were in the outdoor environment. Conclusions: Lichens are effective biological indicators for both outdoor and indoor environments. Furthermore, outdoor emissions could influence IAQ, which could be problematic in densely populated areas such as kindergartens. Mitigation measures should be taken. [ABSTRACT FROM AUTHOR]

The assessment of surface water quality is often laborious, expensive and tedious, as well as impractical, especially for the developing and middle-income countries in the ASEAN region. The application of the water quality index (WQI), which depends on several independent key parameters, has great potential and is a useful tool in this region. Therefore, this study aims to find out the spatial variability of various water quality parameters in geographical information system (GIS) environment and perform a comparative study among the ASEAN WQI systems. At present, there are four ASEAN countries which have implemented the WQI system to evaluate their surface water quality, which are (i) Own WQI system—Malaysia, Thailand and Vietnam—and (ii) Adopted WQI system: Indonesia. A spatial distribution of 12 water quality parameters in the Selangor river basin, Malaysia, was plotted and then applied into the different ASEAN WQI systems. The WQI values obtained from the different WQI systems have an appreciable difference, even for the same water samples due to the disparity in the parameter selection and the standards among them. WQI systems which consider all biophysicochemical parameters provide a consistent evaluation (Very Poor), but the system which either considers physicochemical or biochemical parameters gives a relatively lenient evaluation (Fair–Poor). The Selangor river basin is stressed and impacted by all physical, biological and chemical parameters caused by both the aridity of the climate and anthropogenic activities. Therefore, it is crucial to include all these aspects into the evaluation and corresponding actions should be taken. [ABSTRACT FROM AUTHOR]

The water of Langat River is not suitable for drinking without treatment because of chemical pollution from both the point and non-point pollution sources, although it is one of the primary sources of drinking water in Selangor state, Malaysia. There is no significant study in Malaysia that has investigated the efficiency of treatment plants to remove metals from treated water. Therefore, Chelex 100 resin-ion exchanged method was applied to investigate the raw water samples and treated water samples of eight treatment plants. Samples were analyzed by Inductive Coupled Plasma-Mass Spectrometry for the dissolved concentrations of aluminium, arsenic, cadmium, chromium, and lead, which have complied with the drinking water quality standard of Ministry of Health Malaysia and World Health Organization. However, the average metal removal efficiency is about 52.48 ± 8.89% from treated water by the treatment plants based on a single sampling and this could be considered a preliminary indication to upgrade the treatment technology in Malaysia, because the efficiency in removing trace metals by the plants may vary in hourly samplings. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) and lead (Pb) are ubiquitous metals widely distributed in the environment, resulting in toxic health effects. This project aims to evaluate Pb and Cd as toxic elements in 15 different tobacco cigarette brands produced and/or sold in Selangor state, Peninsular Malaysia. The concentrations of Pb and Cd in all tobacco brands tested in this study were determined using the air-acetylene flame atomic absorption spectrophotometer (AAS). On average, the concentrations of Pb and Cd in different tobacco brand samples ranged from 3.05 and 0.80 μg/g dw, respectively. The results indicate that assessment mean values of Pb inhaled from smoking one packet of 20 cigarettes were in the range of 1.55–3.51 μg. Furthermore, the concentration of Cd inhaled per packet of cigarettes (20 sticks) is estimated to be 0.04–0.36 μg. However, there was a significant difference in the concentrations of Pb and Cd between the different brands of tobacco cigarettes, among cigarette prices (cheap versus expensive) of tobacco brands. In conclusion, cigarette smokers in Selangor, Malaysia, are heavily exposed to Pb and Cd, and such exposure could adversely affect their health in the long term. The impact of toxic heavy metals on smokers in this state would be an area for future research. [ABSTRACT FROM AUTHOR]

This study addresses resolution of a multi-objective land allocation problem and simulation of land change in the south west of Selangor state, Malaysia. The landscape experiences three conflicting objectives of land change, including urban/built-up development, oil palm development, and forest protection. The three conflicting objectives were simultaneously evaluated through developing three distinct sets of driving factors of land change to find a compromised solution to satisfy the requirements of all objectives. The likely patterns of land change were then simulated for the year 2020 based on transitions observed in two periods 1997-2002 and 1997-2008 under a modeling framework that integrates Multi-Criteria Evaluation (MCE), Cellular Automata (CA), and Markov chain analysis. Results showed that in multi-objective land allocation procedure the highest suitability values were given to urban development, oil palm development, and forest protection objective, respectively. Analysis of transition observed showed that although oil palm land use had experienced the highest expansion among other land classes until the year 2002, urban/urban related/built-up land category has experienced the biggest growth in the landscape between 2002 and 2008. Analysis of simulation results revealed that the urban/urban related/built-up areas would highly expand by the year 2020 at the expense of loss of other land categories. Simulations also showed that natural forest covers still could experience more loss than gain by the year 2020 while the loss rate would be lower than the period 2002-2008 but still higher than the period 1997-2002. Results demonstrated an ongoing, but lesser pressure on the natural rainforests in the coming years. [ABSTRACT FROM AUTHOR]

This investigation presents the temporal and spatial distribution of heavy metals (As, Cd, Cr, Cu, Ni, Pb, Hg, and Zn), in water and in sediments of Port Klang, Malaysia. Water and sediment samples were collected from 21 stations at 3-month intervals, and contamination factor $$ (C_{\text{f}} ) $$ and contamination degree $$ (C_{\text{d}} ) $$ were calculated to estimate the contamination status at the sampling stations. Cluster analysis was used to classify the stations based on the contamination sources. Results show that concentrations of As, Cd, Hg, and Pb in sediment and As, Cd, Hg, Pb, Cr, and Zn in water were significantly higher than the background values at which these metals are considered hazardous. The main sources of heavy metal contamination in Port Klang were industrial wastewater and port activities. [ABSTRACT FROM AUTHOR]

An approach based on regional frequency analysis using L moments and LH moments are revisited in this study. Subsequently, an alternative regional frequency analysis using the partial L moments (PL moments) method is employed, and a new relationship for homogeneity analysis is developed. The results were then compared with those obtained using the method of L moments and LH moments of order two. The Selangor catchment, consisting of 37 sites and located on the west coast of Peninsular Malaysia, is chosen as a case study. PL moments for the generalized extreme value (GEV), generalized logistic (GLO), and generalized Pareto distributions were derived and used to develop the regional frequency analysis procedure. PL moment ratio diagram and Z test were employed in determining the best-fit distribution. Comparison between the three approaches showed that GLO and GEV distributions were identified as the suitable distributions for representing the statistical properties of extreme rainfall in Selangor. Monte Carlo simulation used for performance evaluation shows that the method of PL moments would outperform L and LH moments methods for estimation of large return period events. [ABSTRACT FROM AUTHOR]

Surface water is one of the essential resources for supporting sustainable development. The suitability of such water for a given use depends both on the available quantity and tolerable quality. Temporary status for a surface water quality has been identified extensively. Still the suitability of the water for different purposes needs to be verified. This study proposes a water quality evaluation system to assess the aptitude of the Selangor River water for aquatic biota, drinking water production, leisure and aquatic sport, irrigation use, livestock watering, and aquaculture use. Aptitude of the water has been classified in many parts of the river segment as unsuitable for aquatic biota, drinking water production, leisure and aquatic sport as well as aquaculture use. The water quality aptitude classes of the stream water for nine locations along the river are evaluated to contribute to decision support system. The suitability of the water for five different uses and its aquatic ecosystem are verified. [ABSTRACT FROM AUTHOR]

Increasing urbanization and changes in land use in Langat river basin lead to adverse impacts on the environment compartment. One of the major challenges is in identifying sources of organic contaminants. This study presented the application of selected chemometric techniques: cluster analysis (CA), discriminant analysis (DA), and principal component analysis (PCA) to classify the pollution sources in Langat river basin based on the analysis of water and sediment samples collected from 24 stations, monitored for 14 organic contaminants from polycyclic aromatic hydrocarbons (PAHs), sterols, and pesticides groups. The CA and DA enabled to group 24 monitoring sites into three groups of pollution source (industry and urban socioeconomic, agricultural activity, and urban/domestic sewage) with five major discriminating variables: naphthalene, pyrene, benzo[a]pyrene, coprostanol, and cholesterol. PCA analysis, applied to water data sets, resulted in four latent factors explaining 79.0% of the total variance while sediment samples gave five latent factors with 77.6% explained variance. The varifactors (VFs) obtained from PCA indicated that sterols (coprostanol, cholesterol, stigmasterol, β-sitosterol, and stigmastanol) are strongly correlated to domestic and urban sewage, PAHs (naphthalene, acenaphthene, pyrene, benzo[a]anthracene, and benzo[a]pyrene) from industrial and urban activities and chlorpyrifos correlated to samples nearby agricultural sites. The results demonstrated that chemometric techniques can be used for rapid assessment of water and sediment contaminations. [ABSTRACT FROM AUTHOR]

Time-lapse resistivity measurements and groundwater geochemistry were used to study salinity effect on groundwater aquifer at the ex-promontory-land of Carey Island in Malaysia. Resistivity was measured by ABEM Terrameter SAS4000 and ES10-64 electrode selector. Relationship between earth resistivity and total dissolved solids (TDS) was derived, and with resistivity images, used to identify water types: fresh ( ρ > 6.5 Ω m), brackish (3 Ω m < ρ < 6.5 Ω m), or saline ( ρ < 3 Ω m). Long-term monitoring of the studied area's groundwater quality via measurements of its time-lapse resistivity showed salinity changes in the island's groundwater aquifers not conforming to seawater-freshwater hydraulic gradient. In some aquifers far from the coast, saline water was dominant, while in some others, freshwater 30 m thick showed groundwater potential. Land transformation is believed to have changed the island's hydrogeology, which receives saltwater pressure all the time, limiting freshwater recharge to the groundwater system. The time-lapse resistivity measurements showed active salinity changes at resistivity-image bottom moving up the image for two seasons' (wet and dry) conditions. The salinity changes are believed to have been caused by incremental tide passing through highly porous material in the active-salinity-change area. The study's results were used to plan a strategy for sustainable groundwater exploration of the island. [ABSTRACT FROM AUTHOR]

Information related to distributions of rainfall amounts are of great importance for designs of water-related structures. One of the concerns of hydrologists and engineers is the probability distribution for modeling of regional data. In this study, a novel approach to regional frequency analysis using L-moments is revisited. Subsequently, an alternative regional frequency analysis using the TL-moments method is employed. The results from both methods were then compared. The analysis was based on daily annual maximum rainfall data from 40 stations in Selangor Malaysia. TL-moments for the generalized extreme value (GEV) and generalized logistic (GLO) distributions were derived and used to develop the regional frequency analysis procedure. TL-moment ratio diagram and Z-test were employed in determining the best-fit distribution. Comparison between the two approaches showed that the L-moments and TL-moments produced equivalent results. GLO and GEV distributions were identified as the most suitable distributions for representing the statistical properties of extreme rainfall in Selangor. Monte Carlo simulation was used for performance evaluation, and it showed that the method of TL-moments was more efficient for lower quantile estimation compared with the L-moments. [ABSTRACT FROM AUTHOR]

This study investigates the spatial water quality pattern of seven stations located along the main Langat River. Environmetric methods, namely, the hierarchical agglomerative cluster analysis (HACA), the discriminant analysis (DA), the principal component analysis (PCA), and the factor analysis (FA), were used to study the spatial variations of the most significant water quality variables and to determine the origin of pollution sources. Twenty-three water quality parameters were initially selected and analyzed. Three spatial clusters were formed based on HACA. These clusters are designated as downstream of Langat river, middle stream of Langat river, and upstream of Langat River regions. Forward and backward stepwise DA managed to discriminate six and seven water quality variables, respectively, from the original 23 variables. PCA and FA (varimax functionality) were used to investigate the origin of each water quality variable due to land use activities based on the three clustered regions. Seven principal components (PCs) were obtained with 81% total variation for the high-pollution source (HPS) region, while six PCs with 71% and 79% total variances were obtained for the moderate-pollution source (MPS) and low-pollution source (LPS) regions, respectively. The pollution sources for the HPS and MPS are of anthropogenic sources (industrial, municipal waste, and agricultural runoff). For the LPS region, the domestic and agricultural runoffs are the main sources of pollution. From this study, we can conclude that the application of environmetric methods can reveal meaningful information on the spatial variability of a large and complex river water quality data. [ABSTRACT FROM AUTHOR]

Polonium-210 has been measured in the soft parts of Anadara granosa purchased at Kuala Selangor, West Coast of Malaysia in August 2001, April 2002 and September 2002. It is shown that 210Po is non-uniformly distributed within cockles of various sizes (i.e., 2.5, 3.0, 3.5 and 4.0 cm of shell length) and the concentration of 210Po in the soft parts of cockle was significantly different (p<0.05) due to sampling date. The highest value was observed in the smallest cockle with a shell length of 2.5 cm (411.6±26.16 Bq/g dry wt.). It is clear that there is an allometric relationship between 210Po activity concentration and individual cockle weight. This may reflect on the differences of metabolic rate and growth age of cockles. The mean activity concentration of 210Po measured in Kuala Selangor filtered water were 1.75±0.17, 0.79±0.08 and 1.13±0.20 Bq/kg for August 2001, April 2002 and September 2002, respectively. The yield concentration factors for 210Po in the soft parts of cockles varies from 27.3 . 103 to 106.9 . 103. [ABSTRACT FROM AUTHOR]

The article presents a study which aims to analyze the effect of phthalate esters (PEs) residue on the quality of water and sediments in the Klang River Basin in Peninsular Malaysia. The study has established a sampling method and a coding system to examine river water and sediment samples. Results revealed that PEs were present in fortified water samples which shows that there is a lack of proper management of industrial waste discharge from factories near the river.