408 research outputs found

    On Typical Materials Acting as the Dividing Standard of the Development Stages of Human Substance Civilization

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    During more than three million years, the substance civilization of human society went through the Stone Age, the Bronze Age, the Iron Age, the Steel and Cement Age, and the Silicon Age. At the beginning of the new century, the human society has entered into the Nanomaterials Age, which indicates that a completely new substance civilization of human society has started. This paper analyses and discusses why the typical materials serve as the only standard for dividing the eras of the substance civilization of human society. The author argues about the subject of dividing the substance civilization of human society. The goal is to initiate broad and thorough discussion of that subject so as to get a rather thorough understanding about it

    Dynamic landscapes and human dispersal patterns : tectonics, coastlines, and the reconstruction of human habitats

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    Studies of the impact of physical environment on human evolution usually focus on climate as the main external forcing agent of evolutionary and cultural change. In this paper we focus on changes in the physical character of the landscape driven by geophysical processes as an equally potent factor. Most of the landscapes where finds of early human fossils and artefacts are concentrated are ones that have been subjected to high levels of geological instability, either because of especially active tectonic processes associated with faulting and volcanic activity or because of proximity to coastlines subject to dramatic changes of geographical position and physical character by changes of relative sea level. These processes can have both beneficial effects, creating ecologically attractive conditions for human settlement, and deleterious or disruptive ones, creating barriers to movement, disruption of ecological conditions, or hazards to survival. Both positive and negative factors can have powerful selective effects on human behaviour and patterns of settlement and dispersal. We consider both these aspects of the interaction, develop a framework for the reconstruction and comparison of landscapes and landscape change at a variety of scales, and illustrate this with selected examples drawn from Africa and Arabia

    Evidence of stone tools and cutmarked bones dated to 2.44 and 1.92 millions years ago from Aïn Boucherit (Sétif, Algeria) and their implications on the first human occupation in North Africa

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    Recueil de notes séléctionnées au Workshop sur la Géologie du Quaternaire de l’Algérie SÉTIF Les 4 et 5 décembre 2019. Publicado en AlgeriaLes sites pléistocènes inférieurs d'Afrique de l'Est et ceux de Gona (Éthiopie) datés de 2,6 millions d'années en particulier, ont livré les plus anciens outils oldowayens et ossements portant des traces de découpe induites par l'utilisation de ces outils taillés par les hominidés indubitablement reconnus à ce jour. Par comparaison, les artefacts lithiques oldowayens datés d'environs 1,8 million d¿années et recueillis à Aïn Hanech (Algérie) ont été pendant longtemps considérés comme les plus anciens restes archéologiques d'Afrique du Nord. Dans cet article, nous rapportons la découverte récente de traces d'activité humaine plus anciennes. Il s'agit d'outils taillés associés directement à des traces de découpe qui ont été recueillis dans deux niveaux archéologiques distincts (inférieur : AB-Lw, et supérieur : AB-Up) du site de Aïn Boucherit, situé dans la zone d'étude de Aïn Hanech. À l'aide d'une approche multi-méthode combinant le paléomagnétisme, la datation par Résonance Paramagnétique Électronique (RPE ou ESR) et la biochronologie des grands mammifères, l'âge des niveaux archéologiques de Aïn Boucherit est estimé à ~2,44 Ma pour AB-Lw et à ~1,92 Ma pour AB-Up. Ces résultats démontrent que Aïn Boucherit préserve les plus anciennes traces archéologiques connues à ce jour en dehors du Rift Est Africain, révélant ainsi que les premiers hominidés habitaient la frange méditerranéenne en Afrique du Nord beaucoup plus tôt qu'on ne le pensait. Ces preuves plaident fortement en faveur d'une dispersion ancienne et rapide de la manufacture et de l'utilisation d'outils lithiques de type oldowayen depuis l'Afrique de l'Est, ou même d'un scénario d'une possible origine de cette technologie lithique en Afrique de l'Est et en Afrique du Nord

    The burden of HIV/AIDS in Ethiopia from 1990 to 2016: evidence from the Global Burden of Diseases 2016 Study

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    BACKGROUND: The burden of HIV/AIDS in Ethiopia has not been comprehensively assessed over the last two decades. In this study, we used the 2016 Global Burden of Diseases, Injuries and Risk factors (GBD) data to analyze the incidence, prevalence, mortality and Disability-adjusted Life Years Lost (DALY) rates of Human Immunodeficiency Virus / Acquired Immune Deficiency Syndrome (HIV/AIDS) in Ethiopia over the last 26 years. METHODS: The GBD 2016 used a wide range of data source for Ethiopia such as verbal autopsy (VA), surveys, reports of the Federal Ministry of Health and the United Nations (UN) and published scientific articles. The modified United Nations Programme on HIV/AIDS (UNAIDS) Spectrum model was used to estimate the incidence and mortality rates for HIV/AIDS. RESULTS: In 2016, an estimated 36,990 new HIV infections (95% uncertainty interval [UI]: 8775-80262), 670,906 prevalent HIV cases (95% UI: 568,268-798,970) and 19,999 HIV deaths (95% UI: 16426-24412) occurred in Ethiopia. The HIV/AIDS incidence rate peaked in 1995 and declined by 6.3% annually for both sexes with a total reduction of 77% between 1990 and 2016. The annualized HIV/AIDS mortality rate reduction during 1990 to 2016 for both sexes was 0.4%

    Smoking prevalence and attributable disease burden in 195 countries and territories, 1990-2015: a systematic analysis from the Global Burden of Disease Study 2015

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    BACKGROUND: The scale-up of tobacco control, especially after the adoption of the Framework Convention for Tobacco Control, is a major public health success story. Nonetheless, smoking remains a leading risk for early death and disability worldwide, and therefore continues to require sustained political commitment. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) offers a robust platform through which global, regional, and national progress toward achieving smoking-related targets can be assessed. METHODS: We synthesised 2818 data sources with spatiotemporal Gaussian process regression and produced estimates of daily smoking prevalence by sex, age group, and year for 195 countries and territories from 1990 to 2015. We analysed 38 risk-outcome pairs to generate estimates of smoking-attributable mortality and disease burden, as measured by disability-adjusted life-years (DALYs). We then performed a cohort analysis of smoking prevalence by birth-year cohort to better understand temporal age patterns in smoking. We also did a decomposition analysis, in which we parsed out changes in all-cause smoking-attributable DALYs due to changes in population growth, population ageing, smoking prevalence, and risk-deleted DALY rates. Finally, we explored results by level of development using the Socio-demographic Index (SDI). FINDINGS: Worldwide, the age-standardised prevalence of daily smoking was 25·0% (95% uncertainty interval [UI] 24·2-25·7) for men and 5·4% (5·1-5·7) for women, representing 28·4% (25·8-31·1) and 34·4% (29·4-38·6) reductions, respectively, since 1990. A greater percentage of countries and territories achieved significant annualised rates of decline in smoking prevalence from 1990 to 2005 than in between 2005 and 2015; however, only four countries had significant annualised increases in smoking prevalence between 2005 and 2015 (Congo [Brazzaville] and Azerbaijan for men and Kuwait and Timor-Leste for women). In 2015, 11·5% of global deaths (6·4 million [95% UI 5·7-7·0 million]) were attributable to smoking worldwide, of which 52·2% took place in four countries (China, India, the USA, and Russia). Smoking was ranked among the five leading risk factors by DALYs in 109 countries and territories in 2015, rising from 88 geographies in 1990. In terms of birth cohorts, male smoking prevalence followed similar age patterns across levels of SDI, whereas much more heterogeneity was found in age patterns for female smokers by level of development. While smoking prevalence and risk-deleted DALY rates mostly decreased by sex and SDI quintile, population growth, population ageing, or a combination of both, drove rises in overall smoking-attributable DALYs in low-SDI to middle-SDI geographies between 2005 and 2015. INTERPRETATION: The pace of progress in reducing smoking prevalence has been heterogeneous across geographies, development status, and sex, and as highlighted by more recent trends, maintaining past rates of decline should not be taken for granted, especially in women and in low-SDI to middle-SDI countries. Beyond the effect of the tobacco industry and societal mores, a crucial challenge facing tobacco control initiatives is that demographic forces are poised to heighten smoking's global toll, unless progress in preventing initiation and promoting cessation can be substantially accelerated. Greater success in tobacco control is possible but requires effective, comprehensive, and adequately implemented and enforced policies, which might in turn require global and national levels of political commitment beyond what has been achieved during the past 25 years.Bill & Melinda Gates Foundation and Bloomberg Philanthropies
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