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Extent of implementation of food environment policies by the Malaysian Government: gaps and priority recommendations

Ng S, Swinburn B, Kelly B, Vandevijvere S, Yeatman H, Ismail MN, et al.

Public Health Nutr, 2018 Dec;21(18):3395-3406.
PMID: 30277185 DOI: 10.1017/S1368980018002379

OBJECTIVE: To determine the degree of food environment policies that have been implemented and supported by the Malaysian Government, in comparison to international best practice, and to establish prioritised recommendations for the government based on the identified implementation gaps.
DESIGN: The Healthy Food-Environment Policy Index (Food-EPI) comprises forty-seven indicators of government policy practice. Local evidence of each indicator was compiled from government institutions and verified by related government stakeholders. The extent of implementation of the policies was rated by experts against international best practices. Rating results were used to identify and propose policy actions which were subsequently prioritised by the experts based on 'importance' and 'achievability' criteria. The policy actions with relatively higher 'achievability' and 'importance' were set as priority recommendations for government action.
SETTING: Malaysia.
SUBJECTS: Twenty-six local experts.
RESULTS: Majority (62 %) of indicators was rated 'low' implementation with no indicator rated as either 'high' or 'very little, if any' in terms of implementation. The top five recommendations were (i) restrict unhealthy food marketing in children's settings and (ii) on broadcast media; (iii) mandatory nutrition labelling for added sugars; (iv) designation of priority research areas related to obesity prevention and diet-related non-communicable diseases; and (v) introduce energy labelling on menu boards for fast-food outlets.
CONCLUSIONS: This first policy study conducted in Malaysia identified a number of gaps in implementation of key policies to promote healthy food environments, compared with international best practices. Study findings could strengthen civil society advocacies for government accountability to create a healthier food environment.

Matched MeSH terms: Environment
Falls amongst older people in Southeast Asia: a scoping review

Romli MH, Tan MP, Mackenzie L, Lovarini M, Suttanon P, Clemson L

Public Health, 2017 Apr;145:96-112.
PMID: 28359399 DOI: 10.1016/j.puhe.2016.12.035

OBJECTIVES: The older population in the Southeast Asian region is accelerating and is expected to surpass the proportion of the ageing population in North America and Europe in the future. This study aims to identify the research literature related to falls among older people in Southeast Asia, to examine current practice and discuss the future direction on falls prevention and interventions in the region.
STUDY DESIGN: A scoping review design was used.
METHODS: A systematic literature search was conducted using the Medline, CINAHL, AMED, Ageline, PsycINFO, Web of Sciences, Scopus, Thai-Journal Citation Index, MyCite and trial registries databases.
RESULTS: Thirty-seven studies and six study protocols were included, from Thailand, Malaysia, Singapore, Vietnam, Indonesia and the Philippines. One-sixth of the studies involved interventions, while the remainder were observational studies. The observational studies mainly determined the falls risk factors. The intervention studies comprised multifactorial interventions and single interventions such as exercises, educational materials and visual correction. Many of the studies replicated international studies and may not have taken into account features unique to Southeast Asia.
CONCLUSION: Our review has revealed studies evaluating falls and management of falls in the Southeast Asian context. More research is required from all Southeast Asian countries to prepare for the future challenges of managing falls as the population ages.

Matched MeSH terms: Environment Design
Predicting type 2 diabetes using genetic and environmental risk factors in a multi-ethnic Malaysian cohort

Abdullah N, Abdul Murad NA, Mohd Haniff EA, Syafruddin SE, Attia J, Oldmeadow C, et al.

Public Health, 2017 Aug;149:31-38.
PMID: 28528225 DOI: 10.1016/j.puhe.2017.04.003

OBJECTIVE: Malaysia has a high and rising prevalence of type 2 diabetes (T2D). While environmental (non-genetic) risk factors for the disease are well established, the role of genetic variations and gene-environment interactions remain understudied in this population. This study aimed to estimate the relative contributions of environmental and genetic risk factors to T2D in Malaysia and also to assess evidence for gene-environment interactions that may explain additional risk variation.
STUDY DESIGN: This was a case-control study including 1604 Malays, 1654 Chinese and 1728 Indians from the Malaysian Cohort Project.
METHODS: The proportion of T2D risk variance explained by known genetic and environmental factors was assessed by fitting multivariable logistic regression models and evaluating McFadden's pseudo R(2) and the area under the receiver-operating characteristic curve (AUC). Models with and without the genetic risk score (GRS) were compared using the log likelihood ratio Chi-squared test and AUCs. Multiplicative interaction between genetic and environmental risk factors was assessed via logistic regression within and across ancestral groups. Interactions were assessed for the GRS and its 62 constituent variants.
RESULTS: The models including environmental risk factors only had pseudo R(2) values of 16.5-28.3% and AUC of 0.75-0.83. Incorporating a genetic score aggregating 62 T2D-associated risk variants significantly increased the model fit (likelihood ratio P-value of 2.50 × 10(-4)-4.83 × 10(-12)) and increased the pseudo R(2) by about 1-2% and AUC by 1-3%. None of the gene-environment interactions reached significance after multiple testing adjustment, either for the GRS or individual variants. For individual variants, 33 out of 310 tested associations showed nominal statistical significance with 0.001

Matched MeSH terms: Gene-Environment Interaction
Fulltext Impact of mediterranean diet promotion on environmental sustainability: a longitudinal analysis

Álvarez-Álvarez L, Vitelli-Storelli F, Rubín-García M, García S, Bouzas C, Ruíz-Canela M, et al.

Public Health, 2024 May;230:12-20.
PMID: 38479163 DOI: 10.1016/j.puhe.2024.02.010

OBJECTIVE: This article aims to estimate the differences in environmental impact (greenhouse gas [GHG] emissions, land use, energy used, acidification and potential eutrophication) after one year of promoting a Mediterranean diet (MD).
METHODS: Baseline and 1-year follow-up data from 5800 participants in the PREDIMED-Plus study were used. Each participant's food intake was estimated using validated semi-quantitative food frequency questionnaires, and the adherence to MD using the Dietary Score. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The association between MD adherence and its environmental impact was calculated using adjusted multivariate linear regression models.
RESULTS: After one year of intervention, the kcal/day consumed was significantly reduced (-125,1 kcal/day), adherence to a MD pattern was improved (+0,9) and the environmental impact due to the diet was significantly reduced (GHG: -361 g/CO2-eq; Acidification:-11,5 g SO2-eq; Eutrophication:-4,7 g PO4-eq; Energy use:-842,7 kJ; and Land use:-2,2 m2). Higher adherence to MD (high vs. low) was significantly associated with lower environmental impact both at baseline and one year follow-up. Meat products had the greatest environmental impact in all the factors analysed, both at baseline and at one-year follow-up, in spite of the reduction observed in their consumption.
CONCLUSIONS: A program promoting a MD, after one year of intervention, significantly reduced the environmental impact in all the factors analysed. Meat products had the greatest environmental impact in all the dimensions analysed.

Matched MeSH terms: Environment
Thought disorder and its correlation with clinicodemographic variables in schizophrenia

Mazumdar PK, Chaturvedi SK, Gopinath PS

Psychopathology, 1994;27(1-2):37-42.
PMID: 7972638

The correlation of clinical and demographic variables of thought disorder was studied in 45 Research Diagnostic Criteria (RDC) schizophrenics. Thought disorder was assessed by the scale for the assessment of Thought, Language and Communication (TLC). Negative thought disorder was significantly correlated with the rural background. Individual TLC items like Distractible speech, Illogicality, Clanging, Neologisms, etc. were correlated with the literate group and perseveration with the illiterate group. No significant correlation was noted between thought disorder and clinical variables.

Matched MeSH terms: Social Environment
Epidemic hysteria in Malaysian schools: an illustrative episode

Teoh JI, Soewondo S, Sidharta M

Psychiatry, 1975 Aug;38(3):258-68.
PMID: 1197502

This paper discusses the prevalence and characteristics of epidemic hysteria among predominantly rural Malay schools in Malaysia. An illustrative episode in a Malay residential girls' school is described, and contributory factors to this outbreak are elaborated. An attempt is made to analyze the complex interweaving of psychological, religious, cultural, and sociological factors in the precipitation of the outbreak.

Matched MeSH terms: Social Environment
RFamide peptides as mediators in environmental control of GnRH neurons

Parhar I, Ogawa S, Kitahashi T

Prog. Neurobiol., 2012 Aug;98(2):176-96.
PMID: 22684005 DOI: 10.1016/j.pneurobio.2012.05.011

Hypothalamic gonadotropin-releasing hormone (GnRH) is a key hormone for reproductive functions in vertebrates and non-vertebrates. Although GnRH neuronal system is regulated by several factors such as steroids, neurotransmitters and neuropeptides, it is not fully understood how environmental signals control the GnRH neuronal system. RFamide peptides, members of peptides possessing an Arg-Phe-NH(2) motif at their C-terminus, have recently been characterized as major regulators of GnRH neurons. In particular, two key RFamide peptides, kisspeptin and gonadotropin-inhibitory hormone (GnIH), are emerging as important regulators of the reproductive axis. Kisspeptin acts as the accelerator, directly driving GnRH neurons, whereas GnIH acts as the restraint. In addition, other RFamide peptides such as prolactin-releasing peptide (PrRP), PQRFa peptide, 26RFa/QRFP are also known to control reproduction. These RFamide peptides are regulated by environmental factors such as photoperiods, steroid hormones, metabolic signals, and stress. How environmental signals are integrated by RFamide peptides to regulate reproduction through the GnRH neurons?

Matched MeSH terms: Environment*
Fulltext Measuring the potential for sustainable intensification of aquaculture in Bangladesh using life cycle assessment

Henriksson PJG, Belton B, Jahan KM, Rico A

Proc Natl Acad Sci U S A, 2018 03 20;115(12):2958-2963.
PMID: 29507224 DOI: 10.1073/pnas.1716530115

Food production is a major driver of global environmental change and the overshoot of planetary sustainability boundaries. Greater affluence in developing nations and human population growth are also increasing demand for all foods, and for animal proteins in particular. Consequently, a growing body of literature calls for the sustainable intensification of food production, broadly defined as "producing more using less". Most assessments of the potential for sustainable intensification rely on only one or two indicators, meaning that ecological trade-offs among impact categories that occur as production intensifies may remain unaccounted for. The present study addresses this limitation using life cycle assessment (LCA) to quantify six local and global environmental consequences of intensifying aquaculture production in Bangladesh. Production data are from a unique survey of 2,678 farms, and results show multidirectional associations between the intensification of aquaculture production and its environmental impacts. Intensification (measured in material and economic output per unit primary area farmed) is positively correlated with acidification, eutrophication, and ecotoxicological impacts in aquatic ecosystems; negatively correlated with freshwater consumption; and indifferent with regard to global warming and land occupation. As production intensifies, the geographical locations of greenhouse gas (GHG) emissions, acidifying emissions, freshwater consumption, and land occupation shift from the immediate vicinity of the farm to more geographically dispersed telecoupled locations across the globe. Simple changes in fish farming technology and management practices that could help make the global transition to more intensive forms of aquaculture be more sustainable are identified.

Matched MeSH terms: Environment
Fulltext Hunter-gatherer residential mobility and the marginal value of rainforest patches

Venkataraman VV, Kraft TS, Dominy NJ, Endicott KM

Proc Natl Acad Sci U S A, 2017 03 21;114(12):3097-3102.
PMID: 28265058 DOI: 10.1073/pnas.1617542114

The residential mobility patterns of modern hunter-gatherers broadly reflect local resource availability, but the proximate ecological and social forces that determine the timing of camp movements are poorly known. We tested the hypothesis that the timing of such moves maximizes foraging efficiency as hunter-gatherers move across the landscape. The marginal value theorem predicts when a group should depart a camp and its associated foraging area and move to another based on declining marginal return rates. This influential model has yet to be directly applied in a population of hunter-gatherers, primarily because the shape of gain curves (cumulative resource acquisition through time) and travel times between patches have been difficult to estimate in ethnographic settings. We tested the predictions of the marginal value theorem in the context of hunter-gatherer residential mobility using historical foraging data from nomadic, socially egalitarian Batek hunter-gatherers (n = 93 d across 11 residential camps) living in the tropical rainforests of Peninsular Malaysia. We characterized the gain functions for all resources acquired by the Batek at daily timescales and examined how patterns of individual foraging related to the emergent property of residential movements. Patterns of camp residence times conformed well with the predictions of the marginal value theorem, indicating that communal perceptions of resource depletion are closely linked to collective movement decisions. Despite (and perhaps because of) a protracted process of deliberation and argument about when to depart camps, Batek residential mobility seems to maximize group-level foraging efficiency.

Matched MeSH terms: Environment
Fulltext A Review on Citric Acid as Green Modifying Agent and Binder for Wood

Lee SH, Md Tahir P, Lum WC, Tan LP, Bawon P, Park BD, et al.

Polymers (Basel), 2020 Jul 29;12(8).
PMID: 32751175 DOI: 10.3390/polym12081692

Citric acid (CA) can be found naturally in fruits and vegetables, particularly citrus fruit. CA is widely used in many fields but its usage as a green modifying agent and binder for wood is barely addressed. Esterification is one of the most common chemical reactions applied in wood modification. CA contains three carboxyl groups, making it possible to attain at least two esterification reactions that are required for crosslinking when reacting with the hydroxyl groups of the cell wall polymers. In addition, the reaction could form ester linkages to bring adhesivity and good bonding characteristics, and therefore CA could be used as wood binder too. This paper presents a review concerning the usage of CA as a wood modifying agent and binder. For wood modification, the reaction mechanism between wood and CA and the pros and cons of using CA are discussed. CA and its combination with various reactants and their respective optimum parameters are also compiled in this paper. As for the major wood bonding component, the bonding mechanism and types of wood composites bonded with CA are presented. The best working conditions for the CA in the fabrication of wood-based panels are discussed. In addition, the environmental impacts and future outlook of CA-treated wood and bonded composite are also considered.

Matched MeSH terms: Environment
A Comprehensive Review on Advanced Sustainable Woven Natural Fibre Polymer Composites

Aisyah HA, Paridah MT, Sapuan SM, Ilyas RA, Khalina A, Nurazzi NM, et al.

Polymers (Basel), 2021 Feb 02;13(3).
PMID: 33540731 DOI: 10.3390/polym13030471

Over the last decade, the progressive application of natural fibres in polymer composites has had a major effect in alleviating environmental impacts. Recently, there is a growing interest in the development of green materials in a woven form by utilising natural fibres from lignocellulosic materials for many applications such as structural, non-structural composites, household utilities, automobile parts, aerospace components, flooring, and ballistic materials. Woven materials are one of the most promising materials for substituting or hybridising with synthetic polymeric materials in the production of natural fibre polymer composites (NFPCs). These woven materials are flexible, able to be tailored to the specific needs and have better mechanical properties due to their weaving structures. Seeing that the potential advantages of woven materials in the fabrication of NFPC, this paper presents a detailed review of studies related to woven materials. A variety of factors that influence the properties of the resultant woven NFRC such as yarn characteristics, fabric properties as well as manufacturing parameters were discussed. Past and current research efforts on the development of woven NFPCs from various polymer matrices including polypropylene, polylactic acid, epoxy and polyester and the properties of the resultant composites were also compiled. Last but not least, the applications, challenges, and prospects in the field also were highlighted.

Matched MeSH terms: Environment
Fulltext Quantity and configuration of available elephant habitat and related conservation concerns in the Lower Kinabatangan floodplain of Sabah, Malaysia

Estes JG, Othman N, Ismail S, Ancrenaz M, Goossens B, Ambu LN, et al.

PLoS One, 2012;7(10):e44601.
PMID: 23071499 DOI: 10.1371/journal.pone.0044601

The approximately 300 (298, 95% CI: 152-581) elephants in the Lower Kinabatangan Managed Elephant Range in Sabah, Malaysian Borneo are a priority sub-population for Borneo's total elephant population (2,040, 95% CI: 1,184-3,652). Habitat loss and human-elephant conflict are recognized as the major threats to Bornean elephant survival. In the Kinabatangan region, human settlements and agricultural development for oil palm drive an intense fragmentation process. Electric fences guard against elephant crop raiding but also remove access to suitable habitat patches. We conducted expert opinion-based least-cost analyses, to model the quantity and configuration of available suitable elephant habitat in the Lower Kinabatangan, and called this the Elephant Habitat Linkage. At 184 km(2), our estimate of available habitat is 54% smaller than the estimate used in the State's Elephant Action Plan for the Lower Kinabatangan Managed Elephant Range (400 km(2)). During high flood levels, available habitat is reduced to only 61 km(2). As a consequence, short-term elephant densities are likely to surge during floods to 4.83 km(-2) (95% CI: 2.46-9.41), among the highest estimated for forest-dwelling elephants in Asia or Africa. During severe floods, the configuration of remaining elephant habitat and the surge in elephant density may put two villages at elevated risk of human-elephant conflict. Lower Kinabatangan elephants are vulnerable to the natural disturbance regime of the river due to their limited dispersal options. Twenty bottlenecks less than one km wide throughout the Elephant Habitat Linkage, have the potential to further reduce access to suitable habitat. Rebuilding landscape connectivity to isolated habitat patches and to the North Kinabatangan Managed Elephant Range (less than 35 km inland) are conservation priorities that would increase the quantity of available habitat, and may work as a mechanism to allow population release, lower elephant density, reduce human-elephant conflict, and enable genetic mixing.

Matched MeSH terms: Environment
Fulltext The effect of environmental conditions on biofilm formation of Burkholderia pseudomallei clinical isolates

Ramli NS, Eng Guan C, Nathan S, Vadivelu J

PLoS One, 2012;7(9):e44104.
PMID: 22970167 DOI: 10.1371/journal.pone.0044104

Burkholderia pseudomallei, a Gram-negative saprophytic bacterium, is the causative agent of the potentially fatal melioidosis disease in humans. In this study, environmental parameters including temperature, nutrient content, pH and the presence of glucose were shown to play a role in in vitro biofilm formation by 28 B. pseudomallei clinical isolates, including four isolates with large colony variants (LCVs) and small colony variants (SCVs) morphotypes. Enhanced biofilm formation was observed when the isolates were tested in LB medium, at 30 °C, at pH 7.2, and in the presence of as little as 2 mM glucose respectively. It was also shown that all SVCs displayed significantly greater capacity to form biofilms than the corresponding LCVs when cultured in LB at 37 °C. In addition, octanoyl-homoserine lactone (C(8)-HSL), a quorum sensing molecule, was identified by mass spectrometry analysis in bacterial isolates referred to as LCV CTH, LCV VIT, SCV TOM, SCV CTH, 1 and 3, and the presence of other AHL's with higher masses; decanoyl-homoserine lactone (C(10)-HSL) and dodecanoyl-homoserine lactone (C(12)-HSL) were also found in all tested strain in this study. Last but not least, we had successfully acquired two Bacillus sp. soil isolates, termed KW and SA respectively, which possessed strong AHLs degradation activity. Biofilm formation of B. pseudomallei isolates was significantly decreased after treated with culture supernatants of KW and SA strains, demonstrating that AHLs may play a role in B. pseudomallei biofilm formation.

Matched MeSH terms: Environment*
Fulltext Complete killing of Caenorhabditis elegans by Burkholderia pseudomallei is dependent on prolonged direct association with the viable pathogen

Lee SH, Ooi SK, Mahadi NM, Tan MW, Nathan S

PLoS One, 2011;6(3):e16707.
PMID: 21408228 DOI: 10.1371/journal.pone.0016707

Burkholderia pseudomallei is the causative agent of melioidosis, a disease of significant morbidity and mortality in both human and animals in endemic areas. Much remains to be known about the contributions of genotypic variations within the bacteria and the host, and environmental factors that lead to the manifestation of the clinical symptoms of melioidosis.

Matched MeSH terms: Environment
Fulltext Evaluating the relative environmental impact of countries

Bradshaw CJ, Giam X, Sodhi NS

PLoS One, 2010;5(5):e10440.
PMID: 20454670 DOI: 10.1371/journal.pone.0010440

Environmental protection is critical to maintain ecosystem services essential for human well-being. It is important to be able to rank countries by their environmental impact so that poor performers as well as policy 'models' can be identified. We provide novel metrics of country-specific environmental impact ranks - one proportional to total resource availability per country and an absolute (total) measure of impact - that explicitly avoid incorporating confounding human health or economic indicators. Our rankings are based on natural forest loss, habitat conversion, marine captures, fertilizer use, water pollution, carbon emissions and species threat, although many other variables were excluded due to a lack of country-specific data. Of 228 countries considered, 179 (proportional) and 171 (absolute) had sufficient data for correlations. The proportional index ranked Singapore, Korea, Qatar, Kuwait, Japan, Thailand, Bahrain, Malaysia, Philippines and Netherlands as having the highest proportional environmental impact, whereas Brazil, USA, China, Indonesia, Japan, Mexico, India, Russia, Australia and Peru had the highest absolute impact (i.e., total resource use, emissions and species threatened). Proportional and absolute environmental impact ranks were correlated, with mainly Asian countries having both high proportional and absolute impact. Despite weak concordance among the drivers of environmental impact, countries often perform poorly for different reasons. We found no evidence to support the environmental Kuznets curve hypothesis of a non-linear relationship between impact and per capita wealth, although there was a weak reduction in environmental impact as per capita wealth increases. Using structural equation models to account for cross-correlation, we found that increasing wealth was the most important driver of environmental impact. Our results show that the global community not only has to encourage better environmental performance in less-developed countries, especially those in Asia, there is also a requirement to focus on the development of environmentally friendly practices in wealthier countries.

Matched MeSH terms: Environment*
Fulltext What's in a Surname? Physique, Aptitude, and Sports Type Comparisons between Tailors and Smiths

Voracek M, Rieder S, Stieger S, Swami V

PLoS One, 2015;10(7):e0131795.
PMID: 26161803 DOI: 10.1371/journal.pone.0131795

Combined heredity of surnames and physique, coupled with past marriage patterns and trade-specific physical aptitude and selection factors, may have led to differential assortment of bodily characteristics among present-day men with specific trade-reflecting surnames (Tailor vs. Smith). Two studies reported here were partially consistent with this genetic-social hypothesis, first proposed by Bäumler (1980). Study 1 (N = 224) indicated significantly higher self-rated physical aptitude for prototypically strength-related activities (professions, sports, hobbies) in a random sample of Smiths. The counterpart effect (higher aptitude for dexterity-related activities among Tailors) was directionally correct, but not significant, and Tailor-Smith differences in basic physique variables were nil. Study 2 examined two large total-population-of-interest datasets (Austria/Germany combined, and UK: N = 7001 and 20,532) of men's national high-score lists for track-and-field events requiring different physiques. In both datasets, proportions of Smiths significantly increased from light-stature over medium-stature to heavy-stature sports categories. The predicted counterpart effect (decreasing prevalences of Tailors along these categories) was not supported. Related prior findings, the viability of possible alternative interpretations of the evidence (differential positive selection for trades and occupations, differential endogamy and assortative mating patterns, implicit egotism effects), and directions for further inquiry are discussed in conclusion.

Matched MeSH terms: Social Environment; Gene-Environment Interaction
Fulltext An M/M/c/K State-Dependent Model for Pedestrian Flow Control and Design of Facilities

Rahman K, Abdul Ghani N, Kamil AA, Mustafa A, Chowdhury MA

PLoS One, 2015;10(7):e0133229.
PMID: 26196124 DOI: 10.1371/journal.pone.0133229

Pedestrian overflow causes queuing delay and in turn, is controlled by the capacity of a facility. Flow control or blocking control takes action to avoid queues from building up to extreme values. Thus, in this paper, the problem of pedestrian flow control in open outdoor walking facilities in equilibrium condition is investigated using M/M/c/K queuing models. State dependent service rate based on speed and density relationship is utilized. The effective rate of the Poisson arrival process to the facility is determined so as there is no overflow of pedestrians. In addition, the use of the state dependent queuing models to the design of the facilities and the effect of pedestrian personal capacity on the design and the traffic congestion are discussed. The study does not validate the sustainability of adaptation of Western design codes for the pedestrian facilities in the countries like Bangladesh.

Matched MeSH terms: Environment Design*
Fulltext A stochastic simulation framework for the prediction of strategic noise mapping and occupational noise exposure using the random walk approach

Han LM, Haron Z, Yahya K, Bakar SA, Dimon MN

PLoS One, 2015;10(4):e0120667.
PMID: 25875019 DOI: 10.1371/journal.pone.0120667

Strategic noise mapping provides important information for noise impact assessment and noise abatement. However, producing reliable strategic noise mapping in a dynamic, complex working environment is difficult. This study proposes the implementation of the random walk approach as a new stochastic technique to simulate noise mapping and to predict the noise exposure level in a workplace. A stochastic simulation framework and software, namely RW-eNMS, were developed to facilitate the random walk approach in noise mapping prediction. This framework considers the randomness and complexity of machinery operation and noise emission levels. Also, it assesses the impact of noise on the workers and the surrounding environment. For data validation, three case studies were conducted to check the accuracy of the prediction data and to determine the efficiency and effectiveness of this approach. The results showed high accuracy of prediction results together with a majority of absolute differences of less than 2 dBA; also, the predicted noise doses were mostly in the range of measurement. Therefore, the random walk approach was effective in dealing with environmental noises. It could predict strategic noise mapping to facilitate noise monitoring and noise control in the workplaces.

Matched MeSH terms: Environment*
Fulltext Sociodemographic, nutritional, and environmental factors are associated with cognitive performance among Orang Asli children in Malaysia

Murtaza SF, Gan WY, Sulaiman N, Mohd Shariff Z, Ismail SIF

PLoS One, 2019;14(7):e0219841.
PMID: 31306442 DOI: 10.1371/journal.pone.0219841

Children aged 2 to 6 years are in a crucial period of growth development, during which it is important for them to attain specific cognition related to concentration and attention so that they can perform well in school later in life. Various factors influence children's cognition during this crucial period. However, to date, only a limited number of studies have examined the cognitive performance of underprivileged children living in poverty, particularly indigenous children (also known as Orang Asli children in Malaysia). Therefore, this cross-sectional study aimed to determine the associations between sociodemographic factors, nutritional factors (body composition and hemoglobin), and environmental factors (home environment and parasitic infections) with cognitive performance among Orang Asli children in Negeri Sembilan, Malaysia. The participants were 269 children (51% boys, 49% girls) aged 2 to 6 years (M = 4.0, SD = 1.2 years) and their mothers, from 14 Orang Asli villages. Face-to-face interviews were conducted with the mothers, and the children's cognitive performance, operationalized as working memory index (WMI), processing speed index (PSI), and cognitive proficiency index (CPI), was assessed using the Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV). The children's weight and height were measured, and their blood and stool samples were collected to assess hemoglobin level and parasitic infections, respectively. Multiple linear regression analysis showed that the father's years of education (β = 0.262-0.342, p < 0.05), availability of learning materials at home (β = 0.263-0.425, p < 0.05), and responsiveness of the parent to the child (β = 0.192-0.331, p < 0.05) were consistently associated with all three cognitive indices (WMI, PSI, and CPI). A holistic approach involving parents, communities, and government agencies should be established to improve the cognitive performance of these underprivileged children.

Matched MeSH terms: Environment*
Fulltext Statistical Modelling and Characterization of Experimental mm-Wave Indoor Channels for Future 5G Wireless Communication Networks

Al-Samman AM, Rahman TA, Azmi MH, Hindia MN, Khan I, Hanafi E

PLoS One, 2016 Sep 21;11(9):e0163034.
PMID: 27654703 DOI: 10.1371/journal.pone.0163034

This paper presents an experimental characterization of millimeter-wave (mm-wave) channels in the 6.5 GHz, 10.5 GHz, 15 GHz, 19 GHz, 28 GHz and 38 GHz frequency bands in an indoor corridor environment. More than 4,000 power delay profiles were measured across the bands using an omnidirectional transmitter antenna and a highly directional horn receiver antenna for both co- and cross-polarized antenna configurations. This paper develops a new path-loss model to account for the frequency attenuation with distance, which we term the frequency attenuation (FA) path-loss model and introduce a frequency-dependent attenuation factor. The large-scale path loss was characterized based on both new and well-known path-loss models. A general and less complex method is also proposed to estimate the cross-polarization discrimination (XPD) factor of close-in reference distance with the XPD (CIX) and ABG with the XPD (ABGX) path-loss models to avoid the computational complexity of minimum mean square error (MMSE) approach. Moreover, small-scale parameters such as root mean square (RMS) delay spread, mean excess (MN-EX) delay, dispersion factors and maximum excess (MAX-EX) delay parameters were used to characterize the multipath channel dispersion. Multiple statistical distributions for RMS delay spread were also investigated. The results show that our proposed models are simpler and more physically-based than other well-known models. The path-loss exponents for all studied models are smaller than that of the free-space model by values in the range of 0.1 to 1.4 for all measured frequencies. The RMS delay spread values varied between 0.2 ns and 13.8 ns, and the dispersion factor values were less than 1 for all measured frequencies. The exponential and Weibull probability distribution models best fit the RMS delay spread empirical distribution for all of the measured frequencies in all scenarios.

Matched MeSH terms: Environment

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