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Impressions of psychiatry in Singapore, Malaysia, Thailand, and Taiwan

Bennett AE

Biol Psychiatry, 1976 Jun;11(3):345-53.
PMID: 938700
Matched MeSH terms: Population Density
Fulltext Insights into human genetic variation and population history from 929 diverse genomes

Bergström A, McCarthy SA, Hui R, Almarri MA, Ayub Q, Danecek P, et al.

Science, 2020 Mar 20;367(6484).
PMID: 32193295 DOI: 10.1126/science.aay5012

Genome sequences from diverse human groups are needed to understand the structure of genetic variation in our species and the history of, and relationships between, different populations. We present 929 high-coverage genome sequences from 54 diverse human populations, 26 of which are physically phased using linked-read sequencing. Analyses of these genomes reveal an excess of previously undocumented common genetic variation private to southern Africa, central Africa, Oceania, and the Americas, but an absence of such variants fixed between major geographical regions. We also find deep and gradual population separations within Africa, contrasting population size histories between hunter-gatherer and agriculturalist groups in the past 10,000 years, and a contrast between single Neanderthal but multiple Denisovan source populations contributing to present-day human populations.

Matched MeSH terms: Population Density
Genetic Structure and Diversity Among Historic and Modern Populations of the Sumatran Rhinoceros (Dicerorhinus sumatrensis)

Brandt JR, van Coeverden de Groot PJ, Witt KE, Engelbrektsson PK, Helgen KM, Malhi RS, et al.

J Hered, 2018 06 27;109(5):553-565.
PMID: 29684146 DOI: 10.1093/jhered/esy019

The Sumatran rhinoceros (Dicerorhinus sumatrensis), once widespread across Southeast Asia, now consists of as few as 30 individuals within Sumatra and Borneo. To aid in conservation planning, we sequenced 218 bp of control region mitochondrial (mt) DNA, identifying 17 distinct mitochondrial haplotypes across modern (N = 13) and museum (N = 26) samples. Museum specimens from Laos and Myanmar had divergent mtDNA, consistent with the placement of western mainland rhinos into the distinct subspecies D. s. lasiotis (presumed extinct). Haplotypes from Bornean rhinos were highly diverse, but dissimilar from those of other regions, supporting the distinctiveness of the subspecies D. s. harrissoni. Rhinos from Sumatra and Peninsular Malaysia shared mtDNA haplotypes, consistent with their traditional placement into a single subspecies D. s sumatrensis. Modern samples of D. s. sumatrensis were genotyped at 18 microsatellite loci. Rhinos within Sumatra formed 2 sub-populations, likely separated by the Barisan Mountains, though with only modest genetic differentiation between them. There are so few remaining Sumatran rhinoceros that separate management strategies for subspecies or subpopulations may not be viable, while each surviving rhino pedigree is likely to retain alleles found in no other individuals. Given the low population size and low reproductive potential of Sumatran rhinos, rapid genetic erosion is inevitable, though an under-appreciated concern is the potential for fixation of harmful genetic variants. Both concerns underscore 2 overriding priorities for the species: 1) translocation of wild rhinos to ex situ facilities, and 2) collection and storage of gametes and cell lines from every surviving captive and wild individual.

Matched MeSH terms: Population Density
Correlation and persistence of hunting and logging impacts on tropical rainforest mammals

Brodie JF, Giordano AJ, Zipkin EF, Bernard H, Mohd-Azlan J, Ambu L

Conserv Biol, 2015 Feb;29(1):110-21.
PMID: 25196079 DOI: 10.1111/cobi.12389

Humans influence tropical rainforest animals directly via exploitation and indirectly via habitat disturbance. Bushmeat hunting and logging occur extensively in tropical forests and have large effects on particular species. But how they alter animal diversity across landscape scales and whether their impacts are correlated across species remain less known. We used spatially widespread measurements of mammal occurrence across Malaysian Borneo and recently developed multispecies hierarchical models to assess the species richness of medium- to large-bodied terrestrial mammals while accounting for imperfect detection of all species. Hunting was associated with 31% lower species richness. Moreover, hunting remained high even where richness was very low, highlighting that hunting pressure persisted even in chronically overhunted areas. Newly logged sites had 11% lower species richness than unlogged sites, but sites logged >10 years previously had richness levels similar to those in old-growth forest. Hunting was a more serious long-term threat than logging for 91% of primate and ungulate species. Hunting and logging impacts across species were not correlated across taxa. Negative impacts of hunting were the greatest for common mammalian species, but commonness versus rarity was not related to species-specific impacts of logging. Direct human impacts appeared highly persistent and lead to defaunation of certain areas. These impacts were particularly severe for species of ecological importance as seed dispersers and herbivores. Indirect impacts were also strong but appeared to attenuate more rapidly than previously thought. The lack of correlation between direct and indirect impacts across species highlights that multifaceted conservation strategies may be needed for mammal conservation in tropical rainforests, Earth's most biodiverse ecosystems.

Matched MeSH terms: Population Density
Habitat quality and populations of two sympatric gibbons (Hylobatidae) on a mountain in Malaya

Caldecott JO

Folia Primatol., 1980;33(4):291-309.
PMID: 7419138

Sympatric gibbon species Hylobates lar and H. syndactylus were censused on a mountain in Malaya (West Malaysia). Habitat quality was assessed between 380- and 1,525-m altitudes. H. syndactylus was found to occur up to altitudes higher than does H. lar, and this is discussed with reference to the two species' divergent foraging strategies indicated by previous research. It is suggested that gibbons are restricted in their altitudinal range by an increasingly unfavourable ratio of food consumed to energy expended in its location, caused by a reduced food-source density and more difficult terrain at higher elevations.

Matched MeSH terms: Population Density*
The distribution of urban population and income: explorations using six Asian cases

Chakravorty S

GeoJournal, 1993 Feb;29(2):115-24.
PMID: 12318386

"Urban concentration (or primacy) and inequality (in size distribution of income) are expected to follow bell shaped curves through the development process. Spatial convergence (through investments in transportation etc.) is expected to precede income convergence. Using longitudinal data from six Asian countries (Japan, Taiwan, Malaysia, the Philippines, Sri Lanka and India) this paper shows that (i) the bell shapes for urban concentration and income inequality generally hold, and (ii) the temporal relationship between the curve peaks is determined by geographical factors (for urban concentration); income inequality is seen to be more policy amenable."

Matched MeSH terms: Population Density*
Fulltext Inhibiting N-acyl-homoserine lactone synthesis and quenching Pseudomonas quinolone quorum sensing to attenuate virulence

Chan KG, Liu YC, Chang CY

Front Microbiol, 2015;6:1173.
PMID: 26539190 DOI: 10.3389/fmicb.2015.01173

Bacteria sense their own population size, tune the expression of responding genes, and behave accordingly to environmental stimuli by secreting signaling molecules. This phenomenon is termed as quorum sensing (QS). By exogenously manipulating the signal transduction bacterial population behaviors could be controlled, which may be done through quorum quenching (QQ). QS related regulatory networks have been proven their involvement in regulating many virulence determinants in pathogenic bacteria in the course of infections. Interfering with QS signaling system could be a novel strategy against bacterial infections and therefore requires more understanding of their fundamental mechanisms. Here we review the development of studies specifically on the inhibition of production of N-acyl-homoserine lactone (AHL), a common proteobacterial QS signal. The opportunistic pathogen, Pseudomonas aeruginosa, equips the alkylquinolone (AQ)-mediated QS which also plays crucial roles in its pathogenicity. The studies in QQ targeting on AQ are also discussed.

Matched MeSH terms: Population Density
A spatio-temporal overview of urbanization and urban change in Malaysia, with special reference to 1970-1980

Chan Kok Eng

Malays J Reprod Health, 1987 Dec;5(2):127-49.
PMID: 12315183
Matched MeSH terms: Population Density*
Fulltext Differences in Anopheles composition and malaria transmission in the village settlements and cultivated farming zone in Sarawak, Malaysia

Chang MS, Matusop A, Sen FK

Southeast Asian J. Trop. Med. Public Health, 1999 Sep;30(3):454-9.
PMID: 10774651

Anopheles mosquitos were surveyed using three trapping technics in four longhouse settlements and their respectively farming zone in western Sarawak, Malaysia. The study area was mountainous with tropical rain forest. An. leucosphyrus and An. donaldi were predominant in the farm huts. An. tessellatus and An. subpictus were more abundant in the village settlements. In both ecotypes, human baited traps yielded a significantly greater proportion of Anopheles mosquito than CDC light traps and landing biting catches. Circumsporozoite antigen positively rate, mosquito survival rate and parasite rate showed that malaria transmission is more intense in farm huts than in longhouse settlements. The entomological inoculation rate of An. donaldi and An. leucosphyrus in farm huts was 0.035 and 0.023, respectively. No sporozoite infections were observed in the main settlements.

Matched MeSH terms: Population Density
Changes in abundance and behaviour of vector mosquitoes induced by land use during the development of an oil palm plantation in Sarawak

Chang MS, Hii J, Buttner P, Mansoor F

Trans R Soc Trop Med Hyg, 1997 7 1;91(4):382-6.
PMID: 9373626

Surveys were conducted of adult and immature mosquitoes in an area undergoing oil palm development in north Sarawak. Point prevalence data from 2 sites were collected annually, coinciding with annual phases of forest clearing, burning/cultivation, and maintenance. Major habitat perturbation during the forest/clearing transition shifted the major mosquito faunal equilibrium in terms of species composition, relative density and occurrence. Analyses of variance showed that the mean numbers of 4 species of Anopheles decreased significantly after forest clearing. Relative densities of immature stages decreased after forest clearing, but A. letifer and Culex tritaeniorhynchus remained relatively unchanged after the second year. Comparisons with the pre-development forest stage showed that the reductions in person-biting rates, adult survival and combined entomological inoculation rates (EIR) of A. donaldi and A. letifer decreased the risk of malaria transmission by 90% over the 4 years period. Concomitant reductions in EIR and annual malaria incidence were also correlated. This study highlighted the 'law of unintended consequences', since 2 contrasting effects were observed: reduction of malaria vectors but concomitant increase of dengue vectors.

Matched MeSH terms: Population Density
Fulltext Distribution and density of Aedes aegypti (L) and Aedes albopictus (Skuse) in Sarawak

Chang MS, Jute N

Med J Malaysia, 1982 Sep;37(3):205-10.
PMID: 7176997

A total of 73 localities covering 4,894 premises and 26, 712 breeding habitats were surveyed in 1980 to determine and establish the density and distribution pattern of Aedes aegypti and Aedes albopictus in Sarawak. A similar pattern has been observed in the density of the Aedes aegypti and Aedes albopictus. The number of houses positive with Aedes larvae were found to be highest in the coastal areas followed by the inland rural areas. The Aedes aegypti Breteau Index (B.I.) of 0-525 in the coastal areas is the highest followed by 0-207.5 in the inland rural areas. The study undertaken has now revealed that both the Aedes aegypti and Aedes albopictus are widespread in the State.

Matched MeSH terms: Population Density
Fulltext Preliminary study on the effectiveness of mosquito repelling lamp, E Da

Chen CD, Azahari AH, Saadiyah I, Lee HL

Trop Biomed, 2007 Dec;24(2):89-91.
PMID: 18209714 MyJurnal

Photon (light) technology has already been widely used in make-up, medical treatment etc, but repelling mosquitoes by photon technology is an innovation. The objective of this study was to determine the efficacy of a mosquito repelling lamp, E Da under indoor conditions. E Da lamp is a lamp coated with yellow luminous pigment on the inner part of the glass bulb of the lamp which is used to screen out the UV radiation, and when it is turned on, the yellow illuminating wavelength will drive the mosquitoes away. The tests were conducted inside 2 cabins measuring 8' X 8' X 20'. The mosquito population was estimated by using the Bare Leg Catch (BLC) techniques. For treated test, E Da lamp was placed indoor 2 - 3 meters away from a human bait. Another cabin without the lamp was used as untreated control. BLC was conducted in both sites simultaneously. The mosquitoes collected in this study were solely those of Culex quinquefasciatus and Aedes albopictus. There was an 91.34% reduction of Cx. quinquefasciatus population in the treated test compared with the untreated cabin during the 4 hours catches (p < 0.05). E Da mosquito repelling lamp used in this study exerted repellency effect against the mosquitoes especially Cx. quinquefasciatus.

Matched MeSH terms: Population Density
Fulltext Dengue vector surveillance in urban residential and settlement areas in Selangor, Malaysia

Chen CD, Benjamin S, Saranum MM, Chiang YF, Lee HL, Nazni WA, et al.

Trop Biomed, 2005 Jun;22(1):39-43.
PMID: 16880752

Ovitrap surveillance was conducted in two urban residential areas (Taman Samudera Timur and Taman Samudera Selatan) and in a settlement area (Kampung Banjar), which is located 16 km from Kuala Lumpur city center, Malaysia. In Taman Samudera, dengue cases were reported monthly in 2003/2004. Thus, a study was initiated to determine the distribution and abundance of dengue vectors, Aedes aegypti and Ae. albopictus. The ovitrap surveillance indicated that Ae. aegypti and Ae. albopictus were present both indoors and outdoors. The residential sites had 73 - 79% of the ovitraps with just Ae. aegypti population and Kg. Banjar had 56% of the ovitraps with just Ae. aegypti. In the indoor and outdoor of the residential areas, together with the settlement area, the Ae. aegypti density was significantly more than Ae. albopictus (p < 0.05) by 3 - 50 folds. There was no significant difference in the larval numbers of Ae. aegypti between indoors and outdoors (p > 0.05), thus implicating that adult gravid female Ae. aegypti are present both indoors and outdoors and they do oviposit indoors and outdoors. Ae. aegypti can be incriminated as the principal dengue vector in the urban residential site, Taman Samudera and in the settlement area, Kg. Banjar.

Matched MeSH terms: Population Density
Fulltext Assessment of land use factors associated with dengue cases in Malaysia using Boosted Regression Trees

Cheong YL, Leitão PJ, Lakes T

Spat Spatiotemporal Epidemiol, 2014 Jul;10:75-84.
PMID: 25113593 DOI: 10.1016/j.sste.2014.05.002

The transmission of dengue disease is influenced by complex interactions among vector, host and virus. Land use such as water bodies or certain agricultural practices have been identified as likely risk factors for dengue because of the provision of suitable habitats for the vector. Many studies have focused on the land use factors of dengue vector abundance in small areas but have not yet studied the relationship between land use factors and dengue cases for large regions. This study aims to clarify if land use factors other than human settlements, e.g. different types of agricultural land use, water bodies and forest are associated with reported dengue cases from 2008 to 2010 in the state of Selangor, Malaysia. From the correlative relationship, we aim to generate a prediction risk map. We used Boosted Regression Trees (BRT) to account for nonlinearities and interactions between the factors with high predictive accuracies. Our model with a cross-validated performance score (Area Under the Receiver Operator Characteristic Curve, ROC AUC) of 0.81 showed that the most important land use factors are human settlements (model importance of 39.2%), followed by water bodies (16.1%), mixed horticulture (8.7%), open land (7.5%) and neglected grassland (6.7%). A risk map after 100 model runs with a cross-validated ROC AUC mean of 0.81 (±0.001 s.d.) is presented. Our findings may be an important asset for improving surveillance and control interventions for dengue.

Matched MeSH terms: Population Density
The siamang in Malaya. A field study of a primate in tropical rain forest

Chivers DJ

Contrib Primatol, 1974;4:1-335.
PMID: 4474071
Matched MeSH terms: Population Density
Evaluation of liquid baits against field populations of the longlegged ant (Hymenoptera: Formicidae)

Chong KF, Lee CY

J Econ Entomol, 2009 Aug;102(4):1586-90.
PMID: 19736772

An evaluation of several insecticides, namely, 0.01% fipronil, 0.05% indoxacarb, and 2% boric acid in liquid bait formulations were carried out against field populations of the longlegged ant, Anoplolepis gracilipes (Fr. Smith) (Hymenoptera: Formicidae). The baits were formulated in brown cane sugar solution (50%, wt:wt) and placed in an experimental bait station. Each bait was evaluated against populations of A. gracilipes at four buildings. Fipronil, indoxacarb, and boric acid were effective against A. gracilipes, with > 90% reduction of workers within 3 d posttreatment. Total reduction (100%) was achieved within 7 d for fipronil, 14 d for indoxacarb, and 56 d for boric acid. The performance of fipronil and indoxacarb baits did not differ significantly (P > 0.05) in all postbaiting sampling intervals. Reduction of A. gracilipes resulted in an increase in other ant species [Monomorium pharaonis (L.), Monomorium floricola (Jerdon), Monomorium orientale Mayr, Monomorium destructor (Jerdon), Tapinoma indicum Forel, Pheidole sp., and Camponotus sp.] at the baited locations.

Matched MeSH terms: Population Density
Fulltext The Clinical Effectiveness of School Screening Programme for Idiopathic Scoliosis in Malaysia

Deepak AS, Ong JY, Choon D, Lee CK, Chiu CK, Chan C, et al.

Malays Orthop J, 2017 Mar;11(1):41-46.
PMID: 28435573 MyJurnal DOI: 10.5704/MOJ.1703.018

INTRODUCTION: There is no large population size study on school screening for scoliosis in Malaysia. This study is aimed to determine the prevalence rate and positive predictive value (PPV) of screening programme for adolescent idiopathic scoliosis.
MATERIALS AND METHODS: A total of 8966 voluntary school students aged 13-15 years old were recruited for scoliosis screening. Screening was done by measuring the angle of trunk rotation (ATR) on forward bending test (FBT) using a scoliometer. ATR of 5 degrees or more was considered positive. Positively screened students had standard radiographs done for measurement of the Cobb angle. Cobb angle of >10° was used to diagnose scoliosis. The percentage of radiological assessment referral, prevalence rate and PPV of scoliosis were then calculated.
RESULTS: Percentage of radiological assessment referral (ATR >5°) was 4.2% (182/4381) for male and 5.0% (228/4585) for female. Only 38.0% of those with ATR >5° presented for further radiological assessment. The adjusted prevalence rate was 2.55% for Cobb angle >10°, 0.59% for >20° and 0.12% for >40°. The PPV is 55.8% for Cobb angle >10°, 12.8% for >20° and 2.6% for > 40°.
CONCLUSIONS: This is the largest study of school scoliosis screening in Malaysia. The prevalence rate of scoliosis was 2.55%. The positive predictive value was 55.8%, which is adequate to suggest that the school scoliosis screening programme did play a role in early detection of scoliosis. However, a cost effectiveness analysis will be needed to firmly determine its efficacy.

Matched MeSH terms: Population Density
Chigger (Acarina:Trombiculidae) surveys of the west coast beaches of Sabah and Sarawak

Dohany AL, Phang OW, Rapmund G

Southeast Asian J. Trop. Med. Public Health, 1977 Jun;8(2):200-6.
PMID: 411176

Leptotrombidium (Leptotrombidium) arenicola Traub, a vector of scrub typhus, had previously been found to occur in the coastal vegetation behind the edge of open sand along the beaches of Peninsular Malaysia. Surveys of the west coast beaches of Sabah and Sarawak were conducted to determine if this species occurs in similar habitat in East Malaysia on the island of Borneo. Leptotrombidium (L.) arenicola was not collected from the eighteen sites studied. Of the 11,982 mite larvae collected, 55 per cent were L.(L.) deliense (Walch), a well-known, widespread vector of scrub typhus.

Matched MeSH terms: Population Density
Development and human resources in the Islamic world: a study of selected countries

Duza MB

Popul Sci, 1987;7:1-30.
PMID: 12315536

"The present paper attempts to provide an analytical profile of development and human resources in [12] selected [Islamic] countries." The countries--Bangladesh, Somalia, Pakistan, Indonesia, Egypt, Turkey, Malaysia, Algeria, Iraq, Saudi Arabia, Kuwait, and United Arab Emirates--vary in income levels from low to high and in population size from 1 million to 159 million. Using data from the World Bank and the Population Council, comparisons are made on the basis of mortality and fertility levels, family size, income, urbanization, labor force size and growth, education, nutrition, and health. Governmental policy changes and future directions are discussed.

Matched MeSH terms: Population Density*
Sizing Optimization of Hybrid Photovoltaic-Wind-Battery System towards Zero Energy Building using Genetic Algorithm

Farhana Johar, Julies Bong Shu Ai, Fuaada Mohd Siam

MATEMATIKA, 2020;36(3):235-250.
MyJurnal

A new topic of Zero Energy Building (ZEB) is getting famous in research area
because of its goal of reaching zero carbon emission and low building cost. Renewable
energy system is one of the ideas to achieve the objective of ZEB. Genetic Algorithm (GA)
is widely used in many research areas due to its capability to escape from a local minimal
to obtain a better solution. In our study, GA is chosen in sizing optimization of the
number of photovoltaic, wind turbine and battery of a hybrid photovoltaic-wind-battery
system. The aim is to minimize the total annual cost (TAC) of the hybrid energy system
towards the low cost concept of ZEB. Two GA parameters, which are generation number
and population size, have been analysed and optimized in order to meet the minimum
TAC. The results show that the GA is efficient in minimizing cost function of a hybrid
photovoltaic-wind-battery system with its robustness property.

Matched MeSH terms: Population Density

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