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On the statistical study of fertility

Sundrum RM

Malay Econ Rev, 1976;21(2):36-48.
PMID: 12310921
Matched MeSH terms: Population Dynamics
Fulltext 27 years of benthic and coral community dynamics on turbid, highly urbanised reefs off Singapore

Guest JR, Tun K, Low J, Vergés A, Marzinelli EM, Campbell AH, et al.

Sci Rep, 2016 11 08;6:36260.
PMID: 27824083 DOI: 10.1038/srep36260

Coral cover on reefs is declining globally due to coastal development, overfishing and climate change. Reefs isolated from direct human influence can recover from natural acute disturbances, but little is known about long term recovery of reefs experiencing chronic human disturbances. Here we investigate responses to acute bleaching disturbances on turbid reefs off Singapore, at two depths over a period of 27 years. Coral cover declined and there were marked changes in coral and benthic community structure during the first decade of monitoring at both depths. At shallower reef crest sites (3-4 m), benthic community structure recovered towards pre-disturbance states within a decade. In contrast, there was a net decline in coral cover and continuing shifts in community structure at deeper reef slope sites (6-7 m). There was no evidence of phase shifts to macroalgal dominance but coral habitats at deeper sites were replaced by unstable substrata such as fine sediments and rubble. The persistence of coral dominance at chronically disturbed shallow sites is likely due to an abundance of coral taxa which are tolerant to environmental stress. In addition, high turbidity may interact antagonistically with other disturbances to reduce the impact of thermal stress and limit macroalgal growth rates.

Matched MeSH terms: Population Dynamics
The potential of Commelina bengalensis, Amaranthus hybridus, Zea mays for phytoremediation of heavy metals from contaminated soils

Kimenyu P, Oyaro N, Chacha J, Tsanuo M

Sains Malaysiana, 2009;38.

Population in urban centers in Kenya is increasing rapidly due to rural urban migration in search of better paying jobs. This migration has resulted in unauthorized settlements in the various urban centers. The income per capital of these people is less than a dollar a day. The amount of money is inadequate for survival and this has resulted into cultivating on open grounds for food crops. Unfortunately, these slums have come up along rivers, which carry, wastewater from household and industries. This wastewater is rich in heavy metals and the inhabitants of these areas use this contaminated water for irrigating their crops. The food crops from such areas have very high levels of heavy metals. The present study has screened Zea mays, Commelina bengalensis and Amaranthus hybridus for their ability to bioaccumulate these metals from contaminated soils using atomic absorption spectrophotometer (AAS). The results obtained showed that the C. bengalensis has high potential for removal of Cu, Pb and Cd metals as compared to the Zea mays and Amaranthus hybridus even though, results showed that C. bengalensis has a low potential for the removal of Zn as compared to Zea mays and Amaranthus hybridus.

Matched MeSH terms: Population Dynamics
Fulltext Using metapopulation theory for practical conservation of mangrove endemic birds

Huang R, Pimm SL, Giri C

Conserv Biol, 2020 02;34(1):266-275.
PMID: 31183898 DOI: 10.1111/cobi.13364

As a landscape becomes increasingly fragmented through habitat loss, the individual patches become smaller and more isolated and thus less likely to sustain a local population. Metapopulation theory is appropriate for analyzing fragmented landscapes because it combines empirical landscape features with species-specific information to produce direct information on population extinction risks. This approach contrasts with descriptions of habitat fragments, which provide only indirect information on risk. Combining a spatially explicit metapopulation model with empirical data on endemic species' ranges and maps of habitat cover, we calculated the metapopulation capacity-a measure of a landscape's ability to sustain a metapopulation. Mangroves provide an ideal model landscape because they are of conservation concern and their patch boundaries are easily delineated. For 2000-20015, we calculated global metapopulation capacity for 99 metapopulations of 32 different bird species endemic to mangroves. Northern Australia and Southeast Asia had the highest richness of mangrove endemic birds. The Caribbean, Pacific coast of Central America, Madagascar, Borneo, and isolated patches in Southeast Asia in Myanmar and Malaysia had the highest metapopulation losses. Regions with the highest loss of habitat area were not necessarily those with the highest loss of metapopulation capacity. Often, it was not a matter of how much, but how the habitat was lost. Our method can be used by managers to evaluate and prioritize a landscape for metapopulation persistence.

Matched MeSH terms: Population Dynamics
Prevalence of a koinobiont endoparasitoid Misotermes mindeni (Diptera: Phoridae) in colonies of the fungus-growing termite Macrotermes gilvus (Blattodea: Termitidae) in Malaysia

Foo FK, Singham GV, Othman AS, Lee CY

J Econ Entomol, 2011 Oct;104(5):1675-9.
PMID: 22066198

A survey of the infestation rate of colonies of Macrotermes gilvus (Hagen) (Termitidae: Macrotermitinae) with the koinobiont endoparasitoid Misotermes mindeni Disney & Neoh (Diptera: Phoridae) was conducted in Malaysia from September 2009 to January 2011 in the states of Kedah, Penang, Perak, Selangor, Kuala Lumpur, Johor, Terengganu, and Sarawak. Of the 1,125 M. gilvus mounds surveyed, 12.4% contained termites parasitized by M. mindeni and these mounds occurred only in the states of Penang and Perak. High frequencies of mounds containing parasitized termites were found at sites in Penang: Bayan Lepas (21.1%), Minden Campus of Universiti Sains Malaysia ([USM]; 24.5%), Teluk Bahang (28.0%), and Bukit Mertajam (35.0%); the lowest frequency (4.0%) was recorded from Gelugor. The parasitized colonies at all sites were classified as healthy, with exception of several from the Minden Campus of USM (96.4% healthy) and Ayer Itam (87.5% healthy). Most parasitized colonies (71.2%) had a low level of M. mindeni infestation. Only 16.7 and 12.1% of the infested colonies had moderate or high parasite infestation levels, respectively. The height of infected mounds was significantly higher than that of the healthy mounds, but there was no difference between the mound diameters of infested and uninfested mounds. Parasite infestation level was not significantly correlated with mound height or mound diameter. The ambient light intensity at sites with infested mounds was significantly lower than that of uninfested mounds. There was also a significant negative relationship between light intensity and degree of parasitism.

Matched MeSH terms: Population Dynamics
Terror from the sky: unconventional linguistic clues to the negrito past

Blust R

Hum Biol, 2013 Feb-Jun;85(1-3):401-16.
PMID: 24297235

Within recorded history, most Southeast Asian peoples have been of "southern Mongoloid" physical type, whether they speak Austroasiatic, Tibeto-Burman, Austronesian, Tai-Kadai, or Hmong-Mien languages. However, population distributions suggest that this is a post-Pleistocene phenomenon and that for tens of millennia before the last glaciation ended Greater Mainland Southeast Asia, which included the currently insular world that rests on the Sunda Shelf, was peopled by short, dark-skinned, frizzy-haired foragers whose descendants in the Philippines came to be labeled by the sixteenth-century Spanish colonizers as "negritos," a term that has since been extended to similar groups throughout the region. There are three areas in which these populations survived into the present so as to become part of written history: the Philippines, the Malay Peninsula, and the Andaman Islands. All Philippine negritos speak Austronesian languages, and all Malayan negritos speak languages in the nuclear Mon-Khmer branch of Austroasiatic, but the linguistic situation in the Andamans is a world apart. Given prehistoric language shifts among both Philippine and Malayan negritos, the prospects of determining whether disparate negrito populations were once a linguistically or culturally unified community would appear hopeless. Surprisingly, however, some clues to a common negrito past do survive in a most unexpected way.

Matched MeSH terms: Population Dynamics
Temporal changes in arthropod activity in tropical anthropogenic forests

Brandon-Mong GJ, Littlefair JE, Sing KW, Lee YP, Gan HM, Clare EL, et al.

Bull. Entomol. Res., 2018 Dec;108(6):792-799.
PMID: 29441836 DOI: 10.1017/S000748531800010X

Arthropod communities in the tropics are increasingly impacted by rapid changes in land use. Because species showing distinct seasonal patterns of activity are thought to be at higher risk of climate-related extirpation, global warming is generally considered a lower threat to arthropod biodiversity in the tropics than in temperate regions. To examine changes associated with land use and weather variables in tropical arthropod communities, we deployed Malaise traps at three major anthropogenic forests (secondary reserve forest, oil palm forest, and urban ornamental forest (UOF)) in Peninsular Malaysia and collected arthropods continuously for 12 months. We used metabarcoding protocols to characterize the diversity within weekly samples. We found that changes in the composition of arthropod communities were significantly associated with maximum temperature in all the three forests, but shifts were reversed in the UOF compared with the other forests. This suggests arthropods in forests in Peninsular Malaysia face a double threat: community shifts and biodiversity loss due to exploitation and disturbance of forests which consequently put species at further risk related to global warming. We highlight the positive feedback mechanism of land use and temperature, which pose threats to the arthropod communities and further implicates ecosystem functioning and human well-being. Consequently, conservation and mitigation plans are urgently needed.

Matched MeSH terms: Population Dynamics
Fulltext The marital and fertility sentiment orientation of Chinese women and its influencing factors - An analysis based on natural language processing

He Y, Tom Abdul Wahab NE, Muhamad H, Liu D

PLoS One, 2024;19(2):e0296910.
PMID: 38381720 DOI: 10.1371/journal.pone.0296910

BACKGROUND: With the evolution of China's social structure and values, there has been a shift in attitudes towards marriage and fertility, with an increasing number of women holding diverse perspectives on these matters. In order to better comprehend the fundamental reasons behind these attitude changes and to provide a basis for targeted policymaking, this study employs natural language processing techniques to analyze the discourse of Chinese women.
METHODS: The study focused on analyzing 3,200 comments from Weibo, concentrating on six prominent topics linked to women's marriage and fertility. These topics were treated as research cases. The research employed natural language processing techniques, such as sentiment orientation analysis, Word2Vec, and TextRank.
RESULTS: Firstly, the overall sentiment orientation of Chinese women toward marriage and fertility was largely pessimistic. Secondly, the factors contributing to this negative sentiment were categorized into four dimensions: social policies and rights protection, concerns related to parenting, values and beliefs associated with marriage and fertility, and family and societal culture.
CONCLUSION: Based on these outcomes, the study proposed a range of mechanisms and pathways to enhance women's sentiment orientation towards marriage and fertility. These mechanisms encompass safeguarding women and children's rights, promoting parenting education, providing positive guidance on social media, and cultivating a diverse and inclusive social and cultural environment. The objective is to offer precise and comprehensive reference points for the formulation of policies that align more effectively with practical needs.

Matched MeSH terms: Population Dynamics
Fulltext Biodiversity, seasonal abundance, and distribution of blackflies (Diptera: Simuliidae) in six different regions of Thailand

Srisuka W, Takaoka H, Otsuka Y, Fukuda M, Thongsahuan S, Taai K, et al.

Parasit Vectors, 2017 Nov 21;10(1):574.
PMID: 29157269 DOI: 10.1186/s13071-017-2492-y

BACKGROUND: Blackflies are an important medical and veterinary group of small blood-sucking insects. Ninety-three blackfly species have been reported in Thailand. However, information on their biodiversity and population dynamics in each region is lacking. The main aim of this study was to assess the regional biodiversity, seasonal abundance and distribution of blackflies in six eco-geographically different regions in the country.
METHODS: Blackfly larvae and pupae were sampled monthly from 58 sites between May 2011 and April 2013. Diversity parameters, seasonal abundance, regional distribution and frequency of species occurrence in stream sites were analyzed.
RESULTS: A total of 19,456 mature larvae representing 57 species, and belonging to six subgenera in the genus Simulium Latreille (s.l.), were found. The five predominant taxa were S. fenestratum (8.6%), the S. asakoae complex (8.3%), S. nakhonense (7.5%), the S. siamense complex (7.4%) and the S. doipuiense complex (6.7%). The most frequent taxa at all sites were the S. asakoae complex (84.5%), followed by S. fenestratum (82.8%), the S. siamense complex (75.9%), S. decuplum (60.3%), S. nakhonense (58.6%) and the S. tani complex (48.3%). The richness of regional species was highest (40 species) in the north and predominated in the cold season. However, blackflies in the south predominated during the hot season. The highest numbers of blackflies collected from central, northeastern, eastern and western regions of the country were observed in the rainy season. Overall, the mean number of blackflies collected across the six regions during the rainy and cold season had no statistically significant difference, but it differed significantly in the hot season.
CONCLUSIONS: Blackflies in Thailand were surveyed in all three seasons across six geographical regions. These findings demonstrated that blackfly communities at each stream site varied with seasonality, and the regional relative abundance of blackflies differed markedly in the hot season. It was also found that the occurrence and distribution of blackflies in each region were associated strongly with elevation.

Matched MeSH terms: Population Dynamics
Fulltext Demographic History and Genetic Adaptation in the Himalayan Region Inferred from Genome-Wide SNP Genotypes of 49 Populations

Arciero E, Kraaijenbrink T, Asan, Haber M, Mezzavilla M, Ayub Q, et al.

Mol Biol Evol, 2018 Aug 01;35(8):1916-1933.
PMID: 29796643 DOI: 10.1093/molbev/msy094

We genotyped 738 individuals belonging to 49 populations from Nepal, Bhutan, North India, or Tibet at over 500,000 SNPs, and analyzed the genotypes in the context of available worldwide population data in order to investigate the demographic history of the region and the genetic adaptations to the harsh environment. The Himalayan populations resembled other South and East Asians, but in addition displayed their own specific ancestral component and showed strong population structure and genetic drift. We also found evidence for multiple admixture events involving Himalayan populations and South/East Asians between 200 and 2,000 years ago. In comparisons with available ancient genomes, the Himalayans, like other East and South Asian populations, showed similar genetic affinity to Eurasian hunter-gatherers (a 24,000-year-old Upper Palaeolithic Siberian), and the related Bronze Age Yamnaya. The high-altitude Himalayan populations all shared a specific ancestral component, suggesting that genetic adaptation to life at high altitude originated only once in this region and subsequently spread. Combining four approaches to identifying specific positively selected loci, we confirmed that the strongest signals of high-altitude adaptation were located near the Endothelial PAS domain-containing protein 1 and Egl-9 Family Hypoxia Inducible Factor 1 loci, and discovered eight additional robust signals of high-altitude adaptation, five of which have strong biological functional links to such adaptation. In conclusion, the demographic history of Himalayan populations is complex, with strong local differentiation, reflecting both genetic and cultural factors; these populations also display evidence of multiple genetic adaptations to high-altitude environments.

Matched MeSH terms: Population Dynamics
Are Pyrodinium blooms in the Southeast Asian region recurring and spreading? A view at the end of the millennium

Azanza RV, Taylor FJ

Ambio, 2001 Sep;30(6):356-64.
PMID: 11757284

Pyrodinium bahamense (var. compressum) has been the only dinoflagellate species that has caused major public health and economic problems in the Southeast Asian region for more than 2 decades now. It produces saxitoxin, a suite of toxins that cause Paralytic Shellfish Poisoning (PSP). A serious toxicological problem affecting many countries of the world, mild cases of this poisoning can occur within 30 minutes while in extreme cases, death through respiratory paralysis may occur within 2-24 hrs of ingestion of intoxicated shellfish. Blooms of the organism have been reported in Malaysia, Brunei Darussalam, the Philippines and Indonesia. The ASEAN-Canada Red Tide Network has recorded 31 blooms of the organism in 26 areas since 1976 when it first occurred in Sabah, Malaysia. As of 1999, the most hard hit country has been the Philippines which has the greatest number of areas affected (18) and highest number of Paralytic Shellfish Poisoning (PSP) cases (about 1995). Malaysia has reported a total of 609 PSP cases and 44 deaths while Brunei has recorded 14 PSP cases and no fatalities. Indonesia, on the other hand has a record of 427 PSP cases and 17 deaths. Studies on ecological/environmental impacts of these blooms have not been done in the region. Estimates of economic impacts have shown that the loss could be up to USD 300,000 day-1. Most of the data and information useful for understanding Pyrodinium bloom dynamics have come from harmful/toxic algal monitoring and research that have developed to different degrees in the various countries in the region affected by the organism's bloom. Regional collaborative research and monitoring efforts can help harmonize local data sets and ensure their quality and availability for comparative analysis and modeling. Temporal patterns of the blooms at local and regional scales and possible signals and trends in the occurrence/recurrence and spread of Pyrodinium blooms could be investigated. Existing descriptive and simple predictive models of Pyrodinium blooms can be improved and refined to help in the management of the wild harvest and aquaculture of shellfish in a region where the people are dependent on these resources for their daily food sustainance and livelihood.

Matched MeSH terms: Population Dynamics
Fulltext Soils on exposed Sunda shelf shaped biogeographic patterns in the equatorial forests of Southeast Asia

Slik JW, Aiba S, Bastian M, Brearley FQ, Cannon CH, Eichhorn KA, et al.

Proc Natl Acad Sci U S A, 2011 Jul 26;108(30):12343-7.
PMID: 21746913 DOI: 10.1073/pnas.1103353108

The marked biogeographic difference between western (Malay Peninsula and Sumatra) and eastern (Borneo) Sundaland is surprising given the long time that these areas have formed a single landmass. A dispersal barrier in the form of a dry savanna corridor during glacial maxima has been proposed to explain this disparity. However, the short duration of these dry savanna conditions make it an unlikely sole cause for the biogeographic pattern. An additional explanation might be related to the coarse sandy soils of central Sundaland. To test these two nonexclusive hypotheses, we performed a floristic cluster analysis based on 111 tree inventories from Peninsular Malaysia, Sumatra, and Borneo. We then identified the indicator genera for clusters that crossed the central Sundaland biogeographic boundary and those that did not cross and tested whether drought and coarse-soil tolerance of the indicator genera differed between them. We found 11 terminal floristic clusters, 10 occurring in Borneo, 5 in Sumatra, and 3 in Peninsular Malaysia. Indicator taxa of clusters that occurred across Sundaland had significantly higher coarse-soil tolerance than did those from clusters that occurred east or west of central Sundaland. For drought tolerance, no such pattern was detected. These results strongly suggest that exposed sandy sea-bed soils acted as a dispersal barrier in central Sundaland. However, we could not confirm the presence of a savanna corridor. This finding makes it clear that proposed biogeographic explanations for plant and animal distributions within Sundaland, including possible migration routes for early humans, need to be reevaluated.

Matched MeSH terms: Population Dynamics
Single, rapid coastal settlement of Asia revealed by analysis of complete mitochondrial genomes

Macaulay V, Hill C, Achilli A, Rengo C, Clarke D, Meehan W, et al.

Science, 2005 May 13;308(5724):1034-6.
PMID: 15890885

A recent dispersal of modern humans out of Africa is now widely accepted, but the routes taken across Eurasia are still disputed. We show that mitochondrial DNA variation in isolated "relict" populations in southeast Asia supports the view that there was only a single dispersal from Africa, most likely via a southern coastal route, through India and onward into southeast Asia and Australasia. There was an early offshoot, leading ultimately to the settlement of the Near East and Europe, but the main dispersal from India to Australia approximately 65,000 years ago was rapid, most likely taking only a few thousand years.

Matched MeSH terms: Population Dynamics*
Fulltext Individual aspiration or family survival: rural-urban female migration in Malaysia

Kusago T

Asian Pac Migr J, 1998;7(4):483-523.
PMID: 12295220 DOI: 10.1177/011719689800700404

"This paper analyzes the determinants of female migration to export processing zones (EPZs) in Malaysia. A comparison of the individual and household migration models reveals interesting and important contrasting results. First, the role played by the expected net income gains is opposite in the two models: negative in the individual model, positive in the household model. Second, family migration experience is significant in the individual model but not in the household model. Third, attitudes matter to the household decision on a daughter's migration but not in the individual model. These contrasting results suggest that explaining the daughter's migration decision may require more than separation of the individual motives and familial needs."

Matched MeSH terms: Population Dynamics*
On mobility and fertility transitions in east and southeast Asia

Skeldon R

Asian Pac Migr J, 1992;1(2):220-49.
PMID: 12343909

The relationship between fertility and mobility is examined with reference to Zelinsky's [1971] mobility transition hypothesis. Five Asian countries (Japan, South Korea, Thailand, Malaysia, China) at different stages of development and mobility transition are compared with respect to shifting sectoral patterns of migration and changing levels of fertility. National trends suggest that the development sequence proposed by Zelinsky on the basis of the European experience does not generally apply to Asia. In four out of five cases examined, fertility declined before substantial urbanization took place. Zelinsky's sequence of mobility change should be modified to fit the experience of developing countries, but the importance of the interrelations hip between fertility decline and mobility change remains

Matched MeSH terms: Population Dynamics*
Population and development in Asia and the Pacific: a demographic analysis

Debavalya N

Bull Unesco Reg Off Educ Asia Pac, 1982 Jun.
PMID: 12265657
Matched MeSH terms: Population Dynamics*
Population change and some aspects of socio-economic development

UNESCO. Regional Office for Education in Asia and the Pacific

Bull Unesco Reg Off Educ Asia Pac, 1982 Jun.
PMID: 12265663
Matched MeSH terms: Population Dynamics*
The relationship between migration and development in the ESCAP region

Skeldon R

Popul Res Leads, 1991.
PMID: 12317488
Matched MeSH terms: Population Dynamics*
Job transfers: a neglected aspect of migration in Malaysia

Menon R

Int Migr Rev, 1987;21(1):86-95.
PMID: 12314668

"This article examines the incidence of [job-related] transfers in Malaysia. The retrospective migration data from the Malaysia Family Life Survey [conducted in 1976-1977] are used to demonstrate that transfers comprise 18 percent of all migration in the country and that there has been a rise in the incidence of transfers over a 35 year period. Factors underlying this trend are outlined. Furthermore, significant differences in age, educational attainment and other characteristics between transferees and other types of migrants are identified and their implications discussed."

Matched MeSH terms: Population Dynamics*
Comparative Study on Migration, Urbanization and Development in the ESCAP Region (RAS/P13/79). Rev. version

United Nations. Economic and Social Commission for Asia and the Pacific ESCAP

Popul Res Leads, 1982 Jan.
PMID: 12313285
Matched MeSH terms: Population Dynamics*

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