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1.
This study questions the assumption that there is an immutably positive relationship between per capita GNP and per capita energy consumption among human societies. A ratio of per capita GNP to per capita energy consumption ($U.S./kg coal equivalent) is proposed as a measure of energy efficiency for a cross-national analysis of 118 world nation-states and a subset of 25 developed market economies. This ratio is found to vary considerably, between 0.19 and 9.80. A review of literature suggests possible relationships among several sociodemographic characteristics of nations and levels of efficiency with which energy is converted into goods and services. Among the total sample, level of production (measured in terms of per capita GNP) bears a substantial inverse association with energy efficiency. When per capita GNP is held constant, agricultural share of gross domestic product and percentage of labor force in agriculture continue to be positively associated with energy efficiency among the total sample. Variables measuring defense expenditure, urbanization, and population density exhibit somewhat smaller multivariate relationships with energy efficiency when per capita GNP is controlled, i.e., these variables have significant multivariate parameters, but are less closely related to energy efficiency than level of production and agricultural composition of the economy and labor force. Agricultural composition of the economy and labor force is the major predictor of energy efficiency among the subset of 25 developed market economies. The results suggest that among the developed industrial societies level of production is less important than the composition of production activities in determining aggregate energy efficiency.This paper was originally presented at the annual meeting of the North Central Sociological Association, Pittsburgh, Pennsylvania, May 1977. This research was supported by funds from the Michigan Agricultural Experiment Station, the Ohio Agricultural Research and Development Center, and the National Research Council, National Academy of Sciences.  相似文献   

2.
Quality of Life (QOL) is a difficult yet valuable concept to use in regional analysis. It is more telling than purely economic measures, such as per capita GNP, but requires caution in the choice of indicators. The Physical Quality of Life Index (PQLI) is used to evaluate the small island developing countries (SIDCs) of the Indian Ocean. It employs infant mortality, life expectancy at age one, and literacy, which are broadly indicative of a wider range of social and physical attributes. In the Indian Ocean, a bimodalism of results is seen, with Reunion, Mauritius, and Seychelles consistently performing very well, while Maldives and Comoros perform poorly. Other QOL measures are examined as supplementary indicators. The PQLI is seen as an excellent comprehensive device for regional QOL analysis.  相似文献   

3.
Chris T. Bauch 《Oikos》2008,117(12):1824-1832
In modern industrialized countries, human birth rates have been declining persistently for decades. In many cases they have now fallen below the replacement threshold. However, unlike in natural populations where population growth is constrained by limited resources, birth rates in modern industrialized countries are negatively correlated with resource availability. Here, declining birth rates in human populations are shown to be a manifestation of density‐dependent population growth brought on by socioeconomic development. This is demonstrated by combining empirical power law relations between population size, gross domestic product (GDP) per capita, and fertility in a simple theoretical model describing population dynamics in developed countries. For a closed population, the model exhibits growth to a globally stable equilibrium population size, for both national and city populations. A version of the model that is open with respect to immigration and the influence of foreign technology and capital exhibits a good fit to long‐term time series data on population size, GDP per capita, and birth rates for the United States, France and Japan.  相似文献   

4.
世界主要国家耕地动态变化及其影响因素   总被引:10,自引:0,他引:10  
赵文武 《生态学报》2012,32(20):6452-6462
在世界人口持续攀升、全球耕地面积不断减少的背景下,探讨世界主要国家耕地变化其影响因素,对于分析预测未来世界耕地变化趋势、研究世界粮食安全具有积极意义。选择2050年人口过亿的17个国家和耕地面积排名前10的国家为研究对象,在分析1961—2007年耕地总量变化、人均耕地变化的基础上,探讨了耕地变化影响因素。研究结果表明,从20世纪60年代到2007年间的不同时期内,有越来越多的国家表现出耕地减少趋势,而人均耕地面积减少的国家个数高达90%以上。满足人口消费需求、城市化与经济发展是大多数国家耕地总量变化的主要动力;而人口快速增长、城市化则是导致许多国家人均耕地显著减少的重要原因。  相似文献   

5.
A number of research institutions and both local and international agencles in Latin America are using biotechnology as part of an effort to enhance agricultural productivity. However, it is very much an open question as to whether all of these various organizations can provide the best means of realizing this goal. Latin American countries vary dramatically in their knowledge base and current use of modern biotechnology. Thus, while some countries lack the ability to develop, or possibly even implement, many aspects of modern biotechnology, others are quite advanced in this regard. This review provides a somewhat selective overview of current research in the area of agricultural biotechnology in Mexico, Costa Rica and Ecuador, with emphasis on how the existing agencies and institutions have responded to the challenge of biotechnology. In addition, general strategies for the development of agricultural biotechnology in these countries are presented and discussed.  相似文献   

6.
Increased Dependence of Humans on Ecosystem Services and Biodiversity   总被引:1,自引:0,他引:1  
Humans have altered ecosystems more rapidly and extensively than ever, largely to meet rapidly growing demands for resources along with economic development. These demands have been considered important drivers of ecosystem degradation and biodiversity loss. Are humans becoming less dependent on ecosystem services and biodiversity following economic development? Here, we used roundwood production, hydroelectricity generation and tourism investment in 92 biodiversity hotspot and 60 non-hotspot countries as cases to seek the answer. In 1980–2005, annual growth rates of roundwood production, hydroelectricity generation and tourism investment were higher in hotspot countries (5.2, 9.1 and 7.5%) than in non-hotspot countries (3.4, 5.9 and 5.6%), when GDP grew more rapidly in hotspot countries than non-hotspot countries. Annual growth rates of per capita hydropower and per capita tourism investment were higher in hotspot countries (5.3% and 6.1%) than in non-hotspot countries (3.5% and 4.3%); however, the annual growth rate of per capita roundwood production in hotspot countries (1%) was lower than in non-hotspot countries (1.4%). The dependence of humans on cultural services has increased more rapidly than on regulating services, while the dependence on provisioning services has reduced. This pattern is projected to continue during 2005–2020. Our preliminary results show that economic growth has actually made humans more dependent upon ecosystem services and biodiversity. As a consequence, the policies and implementations of both economic development and ecosystems/biodiversity conservation should be formulated and carried out in the context of the increased dependence of humans on ecosystem services along with economic development.  相似文献   

7.
ABSTRACT: BACKGROUND: Greaves "delayed infection" hypothesis suggested that Acute Lymphoblastic Leukemia (ALL) in children is caused by a lack of exposure to infection in infancy, which may be due higher standards of sanitation. We have conducted an ecologic analysis of the relationship between sanitation, using Helicobacter pylori (H. pylori) as the marker, and the incidence of childhood ALL in 127 cancer registries from 28 countries. RESULTS: There were inverse associations between H. pylori perverse and ALL incidence rates in children. These associations were minor and only significant for ALL incidence rates for all cancer registries. They became non-significant and smaller in magnitude when the population source and/or the GNP per capita were added to the relationship. Furthermore, these results were unchanged when the associations were examined using the Generalized Estimating Equations. CONCLUSIONS: Although the findings showed lower prevalence of H. pylori and improved sanitation is associated with increased incidence of childhood ALL, they do not conclusively support Greaves "delayed infection" hypothesis.  相似文献   

8.
The International Study of Asthma and Allergies in Childhood (ISAAC) Phase One showed large worldwide variations in the prevalence of symptoms of asthma, rhinoconjunctivitis and eczema, up to 10 to 20 fold between countries. Ecological analyses were undertaken with ISAAC Phase One data to explore factors that may have contributed to these variations, and are summarised and reviewed here.In ISAAC Phase One the prevalence of symptoms in the past 12 months of asthma, rhinoconjunctivitis and eczema were estimated from studies in 463,801 children aged 13 - 14 years in 155 centres in 56 countries, and in 257,800 children aged 6-7 years in 91 centres in 38 countries. Ecological analyses were undertaken between symptom prevalence and the following: Gross National Product per capita (GNP), food intake, immunisation rates, tuberculosis notifications, climatic factors, tobacco consumption, pollen, antibiotic sales, paracetamol sales, and outdoor air pollution.Symptom prevalence of all three conditions was positively associated with GNP, trans fatty acids, paracetamol, and women smoking, and inversely associated with food of plant origin, pollen, immunisations, tuberculosis notifications, air pollution, and men smoking. The magnitude of these associations was small, but consistent in direction between conditions. There were mixed associations of climate and antibiotic sales with symptom prevalence.The potential causality of these associations warrant further investigation. Factors which prevent the development of these conditions, or where there is an absence of a positive correlation at a population level may be as important from the policy viewpoint as a focus on the positive risk factors. Interventions based on small associations may have the potential for a large public health benefit.  相似文献   

9.
吕天宇  曾晨  刘泽瑾  杨婧 《生态学报》2020,40(24):8974-8987
全球气候变暖已成为21世纪威胁人类可持续发展的严峻挑战,减少CO2排放是抑制气候变暖的重要路径。从全球碳减排的宏观视角出发,以98个国家为研究对象,基于总商品贸易和化石能源贸易的引力模型构建两种空间互动关系,利用扩展后的S-STIRPAT模型对2000、2005、2010年和2014年人均CO2排放的驱动机制和空间溢出效应展开实证分析,并基于发展差异视角进一步探究发达和欠发达国家CO2排放驱动机制异同。研究结果表明:(1)2000、2005、2010年和2014年人均CO2排放溢出效应呈增强态势。(2)城市化水平、人均GDP、能源强度对人均CO2排放产生显著正向影响,可再生能源使用率对人均CO2排放产生显著负向影响。(3)发展差异视角下,城市化水平、人均GDP和能源强度对欠发达国家影响更大,可再生能源使用率对发达国家影响更为显著。根据研究结果建议加强发达国家和欠发达国家低碳技术交流与合作,同时积极调整能源结构以减少CO2排放。  相似文献   

10.
In order to investigate the association between mean inbreeding coefficient (α) and healthy life expectancy at birth (HALE; years) the present ecological study on 63 countries was done. Statistical analysis showed that HALE negatively and positively correlated with log(10)α and log(10)GNI per capita, respectively (p<0.001). It should be noted that log(10)α and log(10)GNI per capita were significantly correlated with each other (p<0.001). After controlling for log(10)GNI per capita, significant negative correlations between log(10)α and HALE were observed. The countries were stratified according to their GNI per capita into low- and high-income countries. In countries with high income, after controlling for log(10)GNI per capita, the correlation between HALE at birth and log(10)α was significant (for males r=-0.399, df=32, p=0.001; for females r=-0.683, df=32, p<0.001). In high-income Asian and African countries, where consanguineous marriage is common, after controlling for log(10)GNI per capita, the correlation between HALE at birth and log(10)α was significant (for males r=-0.819, df=8, p=0.004; for females r=-0.936, df=8, p<0.001). It seems that consanguinity influences HALE independent of country income.  相似文献   

11.
非洲是世界上生物科技最不发达的地区,现代生物科技在许多非洲国家还是新鲜事物。但近年来,非洲国家对生物科技的发展充分重视,不断加强生物人才培养,积极开展国际合作,高度重视生物安全,参与各种UNEP/GEF生物安全计划,并在非盟组织以及国际机构的引导和支持下,成立了生物科技高水平专家组(ABP),撰写了“非洲生物技术发展报告”提出非洲生物技术发展构想。了解和研究非洲生物科技发展现状及动态对我国生物科技的发展以及开展中非合作有着重要的意义。  相似文献   

12.
Biotechnology is becoming a crucial factor for the innovation strategies of the industrialised countries. Thus, the analysis of the sector is gaining relevance for the identification of the technological strength and potential of a country (or region) in a context of globalisation. A specific national case study may serve for more general comparative analyses. We have selected the case of Spain as illustrative of the complexity and differences existing in Europe. By using the analytical framework of the "national systems of innovation" concept, we have performed a multistep analysis of the biotechnology sector in Spain, focussing first on regions of Madrid and Catalu?a which together account for more than 50% of the sector in Spain. The firms in both regions have followed a common strategy based on diversification and investment in R&D and innovation, so as to be able to compete in an international and competitive environment. There are, however, some interesting differences between the two subsectors; the one from Catalu?a being more based on industrial traditions, and the one from Madrid characterised by the emergence of more specialised firms. The study has been extended to the remainder of Spanish firms for comparative purposes. The case of Spain is illustrative of the divergences existing in the biotechnology sector in Europe. A comparison is made with the structural and organisational characteristics of the biotechnology sector in several European countries. It shows that there is diversity in the pattern of commercialisation between countries and within regions of countries. Understanding these differences may assist the design of appropriate policies to promote the development of biotechnology in Europe.  相似文献   

13.
长株潭地区生态可持续性   总被引:7,自引:0,他引:7  
戴亚南  贺新光 《生态学报》2013,33(2):595-602
基于长株潭地区被批准为“全国资源节约型和环境友好型社会建设综合配套改革试验区”的背景,针对生态足迹方法的产量因子参数进行改进,利用区域产量因子代替全球产量因子,对长株潭地区1986-2005年生态足迹和生态承载力进行核算,在此基础上,着重采用两种预测方法对该地区2007-2015年生态足迹和生态容量进行预测.两种预测方法分别是二项式曲线预测模型和灰色GM(1,1)模型,对长株潭地区1986-2005年20a的人均生态足迹与时间关系进行了拟合,得出二项式曲线预测模型具有更高的预测精度;用两种预测模型预测了长株潭地区的人均生态容量,GM(1,1)模型的预测精度更高.选取精度最高的模型分别预测研究区未来10a人均生态足迹和生态容量.未来10a人均生态容量增长平缓(年平均增长率1.8%),人均生态足迹增长快(年平均增长率达16%),相应的人均生态赤字增长快.  相似文献   

14.
全球温室气体排放概况   总被引:7,自引:0,他引:7  
全球温室气体排放概况曹志平(中国农业大学资源与环境学院生态系,北京100094)IntroductionofGlobalEmissionsofGreenhouseGas.CaoZhiping(ColegeofResourcesandEnvironm...  相似文献   

15.
BACKGROUND: Nigeria has the tenth highest burden of tuberculosis (TB) among the 22 TB high-burden countries in the world. This study describes the biodiversity and epidemiology of drug-susceptible and drug-resistant TB in Ibadan, Nnewi and Abuja, using 409 DNAs extracted from culture positive TB isolates. METHODOLOGY/PRINCIPAL FINDINGS: DNAs extracted from clinical isolates of Mycobacterium tuberculosis complex were studied by spoligotyping and 24 VNTR typing. The Cameroon clade (CAM) was predominant followed by the M. africanum (West African 1) and T (mainly T2) clades. By using a smooth definition of clusters, 32 likely epi-linked clusters related to the Cameroon genotype family and 15 likely epi-linked clusters related to other "modern" genotypes were detected. Eight clusters concerned M. africanum West African 1. The recent transmission rate of TB was 38%. This large study shows that the recent transmission of TB in Nigeria is high, without major regional differences, with MDR-TB clusters. Improvement in the TB control programme is imperative to address the TB control problem in Nigeria.  相似文献   

16.
近年来,使用抗生素的副作用越来越多地受到关注,世界上许多国家已出台相应政策来控制抗生素的使用。但是由于养殖行业的迅猛发展,养殖密度加大,养殖动物病害发病的风险提高,急需可替代抗生素的新型绿色饲料添加剂产品。微生态制剂作为一种新型绿色饲料添加剂,在养殖行业发挥了重要作用。随着饲用微生态制剂产品研发的深入,现代生物技术在提升微生态制剂的理论和应用研究方面发挥着重要作用。PCR、核酸分子杂交、基因工程以及组学等技术已应用于微生物菌种鉴定、基因改良、作用机理等研究中。本文对饲用微生态制剂的研发现状进行了阐述,并综述了现代生物技术在饲用微生态制剂研究中的应用。  相似文献   

17.
Regression analyses were conducted between water pollutants discharges per capita (PDC) and gross domestic production per capita (GDPC) of developing countries in seven international coastal and lakeside Regions. Regional groupings of PDCs and GDPC were identified with graphical analyses. The inverted-U shaped curve relationships, namely environmental Kuznets curve (EKC), were found for biological oxygen demand (BOD) discharge per capita (PDC-BOD) and total phosphorus (TP) discharge per capita (PDC-TP) with a peak at ca. US$5, 050 and US$11,200, respectively, besides lower significance for PDC-BOD. Total nitrogen (TN) discharge per capita (PDC-TN) decreased linearly with GDPC increase. Possible reasons for the different tendencies of PDC-BOD, PDC-TN and PDC-TP with GCP per capita are that nutrient removal is introduced after economic development to some extent, and main nitrogen source is blackwater especially urine in domestic wastewater. Pollutants discharges reduction should be targeted with the relevant indicators to improve the ambient water quality especially after the achievement of the sanitation millennium development goals (MDGs) because the sanitation MDGs indicator mainly targets infectious diseases, hygiene health and lifestyle improvement, and there are several kinds of domestic wastewater treatment methods in the world.  相似文献   

18.

Background and Purpose

Stroke accounts for more than 10% of all deaths globally and most of it occurs in low- and middle-income countries (LMIC). Income inequality and gross domestic product (GDP) per capita has been associated to stroke mortality in developed countries. In LMIC, GDP per capita is considered to be a more relevant health determinant than income inequality. This study aims to investigate if income inequality is associated to stroke mortality in Brazil at large, but also on regional and state levels, and whether GDP per capita modulates the impact of this association.

Methods

Stroke mortality rates, Gini index and GDP per capita data were pooled for the 2002 to 2009 period from public available databases. Random effects models were fitted, controlling for GDP per capita and other covariates.

Results

Income inequality was independently associated to stroke mortality rates, even after controlling for GDP per capita and other covariates. GDP per capita reduced only partially the impact of income inequality on stroke mortality. A decrease in 10 points in the Gini index was associated with 18% decrease in the stroke mortality rate in Brazil.

Conclusions

Income inequality was independently associated to stroke mortality in Brazil.  相似文献   

19.
Fluorescence microsatellite markers were employed to reveal genetic diversity of 340 wheat accessions consisting of 229 landraces and 111 modern varieties from the Northwest Spring Wheat Region in China. The 340 accessions were chosen as candidate core collections for wheat germplasm in this region. A core collection representing the genetic diversity of these accessions was identified based on a cluster dendrogram of 78 SSR loci. A total of 967 alleles were detected with a mean of 13.6 alleles (5–32) per locus. Mean PIC was 0.64, ranged from 0.05 to 0.91. All loci were distributed relatively evenly in the A, B and D wheat genomes. Mean genetic richness of A, B and D genomes for both landraces and modern varieties was B > A > D. However, mean genetic diversity indices of landraces changed to B > D > A. As a whole, genetic diversity of the landraces was considerably higher than that of the modern varieties. The big difference of genetic diversity indices in the three genomes suggested that breeding has exerted greater selection pressure in the D than the A or B genomes in this region. Changes of allelic proportions represented in the proposed core collection at different sampling scales suggested that the sampling percentage of the core collection in the Northwest Spring Wheat Region should be greater than 4% of the base collection to ensure that more than 70% of the variation is represented by the core collection. Electronic supplementary material Electronic supplementary material is available for this article at and accessible for authorised users.  相似文献   

20.
Bioinformatics involves the collection, organization and analysis of large amounts of biological data, using networks of computers and databases. Developing countries in the Asia-Pacific region are just moving into this new field of information-based biotechnology. However, the computational infrastructure and network bandwidths available in these countries are still at a basic level compared to that in developed countries. In this study, we assessed the utility of a BitTorrent-based Peer-to-Peer (btP2P) file distribution model for automatic synchronization and distribution of large amounts of biological data among developing countries. The initial country-level nodes in the Asia-Pacific region comprised Thailand, Korea and Singapore. The results showed a significant improvement in download performance using btP2P--three times faster overall download performance than conventional File Transfer Protocol (FTP). This study demonstrated the reliability of btP2P in the dissemination of continuously growing multi-gigabyte biological databases across the three Asia-Pacific countries. The download performance for btP2P can be further improved by including more nodes from other countries into the network. This suggests that the btP2P technology is appropriate for automatic synchronization and distribution of biological databases and software over low-bandwidth networks among developing countries in the Asia-Pacific region. AVAILABILITY: http://everest.bic.nus.edu.sg/p2p/  相似文献   

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