Population Control for Zero Growth in Singapore.

1981 ◽  
Vol 35 (2) ◽  
pp. 334
Author(s):  
T. E. Smith ◽  
Saw Swee-Hock
2010 ◽  
Vol 32 (1) ◽  
pp. 11 ◽  
Author(s):  
A. R. Pople ◽  
S. R. McLeod

Since their release over 100 years ago, camels have spread across central Australia and increased in number. Increasingly, they are being seen as a pest, with observed impacts from overgrazing and damage to infrastructure such as fences. Irregular aerial surveys since 1983 and an interview-based survey in 1966 suggest that camels have been increasing at close to their maximum rate. A comparison of three models of population growth fitted to these, albeit limited, data suggests that the Northern Territory population has indeed been growing at an annual exponential rate of r = 0.074, or 8% per year, with little evidence of a density-dependent brake. A stage-structured model using life history data from a central Australian camel population suggests that this rate approximates the theoretical maximum. Elasticity analysis indicates that adult survival is by far the biggest influence on rate of increase and that a 9% reduction in survival from 96% is needed to stop the population growing. In contrast, at least 70% of mature females need to be sterilised to have a similar effect. In a benign environment, a population of large mammals such as camels is expected to grow exponentially until close to carrying capacity. This will frustrate control programs, because an ever-increasing number of animals will need to be removed for zero growth the longer that culling or harvesting effort is delayed. A population projection for 2008 suggests ~10 500 animals need to be harvested across the Northern Territory. Current harvests are well short of this. The ability of commercial harvesting to control camel populations in central Australia will depend on the value of animals, access to animals and the presence of alternative species to harvest when camels are at low density.


1982 ◽  
Vol 11 (2) ◽  
pp. 188
Author(s):  
Allan Schnaiberg ◽  
Saw Swee-Hock

1972 ◽  
Author(s):  
Thomas Poffenberger ◽  
Robert Buckhout ◽  
Martin Rosenman ◽  
Eugene Weiss ◽  
Nancy Russo

2016 ◽  
Vol 38 (1) ◽  
pp. 47-65
Author(s):  
Keith Clavin

The last several decades have witnessed a drastic increase in ecological writing, but also a substantial lack in regards to the discussion of human population control. This article argues that the deficiency has been reproduced within several recent examples of eco-cinema, Snowpiercer and Mad Max: Fury Road. Despite strong conservationist themes and narratives encouraging social revolution, the films encounter similar theoretical difficulties, and enact similar resulting absences, within their representational fields. As a consequence, the environmental topics are filtered through an anthropocentric lens that generates a set of paradoxes regarding human consumption, sacrifice and the visualisation of future sustainable states.


Author(s):  
J.E. Azimova ◽  
E.A. Klimov ◽  
E.A. Naumova ◽  
Z.G. Kokaeva ◽  
A.I. Zaitseva ◽  
...  

Перспективным в изучении биомаркеров мигрени может быть многолокусный анализ, в частности, анализ частот сочетанных генотипов. Цель исследования - поиск составных генетических биомаркеров индивидуальной предрасположенности к мигрени, полученных на основе полиморфизмов генов, уже показавших статистическую значимость при однолокусном ассоциативном анализе. Методика. Обследовано 155 пациентов с мигренью (104 пациента с эпизодической мигренью, 51 - с хронической мигренью), наблюдавшихся в Университетской клинике головной боли (Москва). Все пациенты - представители белой расы, жители Московского региона. Возраст пациентов - 30-50 лет. Контроль составили 365 необследованных лиц (популяционный контроль). Выявление исследуемых 22 генов (всего 31 SNP) осуществляли методом ПЦР, ПЦР-ПДРФ, аллель-специфичной ПЦР и ПЦР в реальном времени. Выявление ассоциированных с мигренью сочетанных генотипов проводили с использованием программы анализа полигенных данных APSampler v3.6. Результаты. Выявлено 8 сочетанных генотипов с высокой статистически значимой ассоциацией с мигренью (ОШ>20,0). В состав сочетанных генотипов вошли гены: CCKAR, CCKBR, COMT, MTHFR, MTR, MTRR. Так же выявлено 4 защитных сочетанных генотипа (ОШ<0,02), основным в которых является ген MAOA. Заключение. Полученные данные об ассоциированных с мигренью сочетанных генотипах указывают на значимую роль в патогенезе заболевания 2 биохимических систем: 1) холецистокининергической системы, регулирующей выброс и обратный захват дофамина, и 2) фолатного цикла, в ходе работы которого гомоцистеин метаболизируется в метионин. Результаты, полученные в данном исследовании, позволяют говорить о защитной роли аллеля VNT:R4 гена MAOA.Multilocus analysis, specifically, analysis of combined genotype frequencies may be promising in studying migraine biomarkers. The aim of the study was to search for composite genetic biomarkers, which would predict individual predisposition to migraine, obtained on the basis of gene polymorphisms that have already shown a statistical significance in a single-locus associative analysis. Methods. 155 patients with migraine aging 41.7 ± 12.5 who had been followed up at the University Clinic of Headache, Moscow, were evaluated (104 patients with episodic migraine and 51 with chronic migraine). All patients were white and residents of the Moscow region. The control group included 365 unexamined individuals (population control). Identification of The 22 genes under study (total, 31 SNPs) were identified by PCR, PCR-RFLP, allele-specific PCR, and real-time PCR. Combined genotypes associated with migraine were identified using the APSampler v3.6 software for polygenic data analysis. Results. Eight combined genotypes were identified with a highly significant association with migraine (OR> 20.0). The combined genotypes included the CCKAR, CCKBR, COMT, MTHFR, MTR, and MTRR genes. Four protective combined genotypes were also identified (OS <0.02) with the MAOA gene as the major one. Conclusion. Our data on migraine-associated combined genotypes indicate a significant role in the migraine pathogenesis of two biochemical systems, i) the cholecystokininergic system that regulates the release and reuptake of dopamine, and ii) the folate cycle, where homocysteine is metabolized to methionine. The results obtained in this study suggest a protective role of the VNT: R4 allele of the MAOA gene.


1977 ◽  
Vol 16 (2) ◽  
pp. 220-222
Author(s):  
Zeba A. Sathar

The book covers a wide field, touching on almost all aspects of popula¬tion change on a world-wide scale. It discusses, using world and country data, the relationships between demographic and socio-economic variables, and elaborates on" their relative importance in the determination of population problems which confront the world as a whole and nations individually. Policies designed to alleviate these problems are discussed with an emphasis on those related to population control. The first chapter is entitled "Population Growth: Past and Prospective" and reviews the various parameters associated with population change in the past and in the future. It touches upon the concept of a stable population in order to show the elements which cause a population to change (i.e. remove it from its stable condition). The main elements of change, population growth, migration, mortality and natality are discussed individually. The chapter is concluded by a description of the main differences in these elements and other socio-economic conditions as they exist in the less-developed and developed countries.


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