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Sample records for prehistoric agricultural depletion

  1. Prehistoric agricultural depletion of soil nutrients in Hawai'i.

    PubMed

    Hartshorn, A S; Chadwick, O A; Vitousek, P M; Kirch, P V

    2006-07-18

    We investigated the fate of soil nutrients after centuries of indigenous dryland agriculture in Hawai'i using a coupled geochemical and archaeological approach. Beginning approximately 500 years ago, farmers began growing dryland taro and sweet potato on the leeward slopes of East Maui. Their digging sticks pierced a subsurface layer of cinders, enhancing crop access to the soil water stored below the intact cinders. Cultivation also catalyzed nutrient losses, directly by facilitating leaching of mobile nutrients after disturbing a stratigraphic barrier to vertical water movement, and indirectly by increasing mineral weathering and subsequent uptake and harvest. As a result, centuries of cultivation lowered volumetric total calcium, magnesium, sodium, potassium, and phosphorus content by 49%, 28%, 75%, 37%, and 32%, respectively. In the absence of written records, we used the difference in soil phosphorus to estimate that prehistoric yields were sufficient to meet local demand over very long time frames, but the associated acceleration of nutrient losses could have compromised subsequent yields.

  2. Water Depletion Threatens Agriculture

    NASA Astrophysics Data System (ADS)

    Brauman, K. A.; Richter, B. D.; Postel, S.; Floerke, M.; Malsy, M.

    2014-12-01

    Irrigated agriculture is the human activity that has by far the largest impact on water, constituting 85% of global water consumption and 67% of global water withdrawals. Much of this water use occurs in places where water depletion, the ratio of water consumption to water availability, exceeds 75% for at least one month of the year. Although only 17% of global watershed area experiences depletion at this level or more, nearly 30% of total cropland and 60% of irrigated cropland are found in these depleted watersheds. Staple crops are particularly at risk, with 75% of global irrigated wheat production and 65% of irrigated maize production found in watersheds that are at least seasonally depleted. Of importance to textile production, 75% of cotton production occurs in the same watersheds. For crop production in depleted watersheds, we find that one half to two-thirds of production occurs in watersheds that have not just seasonal but annual water shortages, suggesting that re-distributing water supply over the course of the year cannot be an effective solution to shortage. We explore the degree to which irrigated production in depleted watersheds reflects limitations in supply, a byproduct of the need for irrigation in perennially or seasonally dry landscapes, and identify heavy irrigation consumption that leads to watershed depletion in more humid climates. For watersheds that are not depleted, we evaluate the potential impact of an increase in irrigated production. Finally, we evaluate the benefits of irrigated agriculture in depleted and non-depleted watersheds, quantifying the fraction of irrigated production going to food production, animal feed, and biofuels.

  3. From Paleoclimate Variables to Prehistoric Agriculture: Using a Process-Based Agroecosystem Model to Simulate Prehistoric Agricultural Productivity

    NASA Astrophysics Data System (ADS)

    Contreras, Daniel; Bondeau, Alberte; Guiot, Joël; Kirman, Alan; Hiriart, Eneko; Bernard, Loup; Suarez, Romain; Fader, Marianela

    2016-04-01

    This paper explores the relationship between past climate and prehistoric Mediterranean agriculture by adapting a process-based dynamic vegetation model to estimate past agricultural productivity under climate scenarios that characterize the extremes of Mediterranean climate (warm/wet and cold/dry) in the Holocene. We adapt LPJmL (the Lund-Potsdam-Jena-managed-landscape model, (cf. Bondeau et al. 2007)) to the modeling of past agricultural productivity. Calibrating this model for past crops and agricultural practices and using a combined downsampling and simulation approach to produce high spatiotemporal resolution paleoclimate data, we simulate realistic potential agricultural yields under past climatic conditions derived from the Holocene climatic extremes. We here discuss this process with reference to a case study in Provence, examining the methodology and data requirements for modeling past agriculture using LPJmL as well as the potential range of variability in agricultural productivity under distinct climate conditions. We focus on comparing the range of variability induced by climatic shifts with that achievable through changes in agricultural practices.

  4. Diet adaptation in dog reflects spread of prehistoric agriculture.

    PubMed

    Arendt, M; Cairns, K M; Ballard, J W O; Savolainen, P; Axelsson, E

    2016-11-01

    Adaptations allowing dogs to thrive on a diet rich in starch, including a significant AMY2B copy number gain, constituted a crucial step in the evolution of the dog from the wolf. It is however not clear whether this change was associated with the initial domestication, or represents a secondary shift related to the subsequent development of agriculture. Previous efforts to study this process were based on geographically limited data sets and low-resolution methods, and it is therefore not known to what extent the diet adaptations are universal among dogs and whether there are regional differences associated with alternative human subsistence strategies. Here we use droplet PCR to investigate worldwide AMY2B copy number diversity among indigenous as well as breed dogs and wolves to elucidate how a change in dog diet was associated with the domestication process and subsequent shifts in human subsistence. We find that AMY2B copy numbers are bimodally distributed with high copy numbers (median 2nAMY2B=11) in a majority of dogs but no, or few, duplications (median 2nAMY2B=3) in a small group of dogs originating mostly in Australia and the Arctic. We show that this pattern correlates geographically to the spread of prehistoric agriculture and conclude that the diet change may not have been associated with initial domestication but rather the subsequent development and spread of agriculture to most, but not all regions of the globe.

  5. Diet adaptation in dog reflects spread of prehistoric agriculture

    PubMed Central

    Arendt, M; Cairns, K M; Ballard, J W O; Savolainen, P; Axelsson, E

    2016-01-01

    Adaptations allowing dogs to thrive on a diet rich in starch, including a significant AMY2B copy number gain, constituted a crucial step in the evolution of the dog from the wolf. It is however not clear whether this change was associated with the initial domestication, or represents a secondary shift related to the subsequent development of agriculture. Previous efforts to study this process were based on geographically limited data sets and low-resolution methods, and it is therefore not known to what extent the diet adaptations are universal among dogs and whether there are regional differences associated with alternative human subsistence strategies. Here we use droplet PCR to investigate worldwide AMY2B copy number diversity among indigenous as well as breed dogs and wolves to elucidate how a change in dog diet was associated with the domestication process and subsequent shifts in human subsistence. We find that AMY2B copy numbers are bimodally distributed with high copy numbers (median 2nAMY2B=11) in a majority of dogs but no, or few, duplications (median 2nAMY2B=3) in a small group of dogs originating mostly in Australia and the Arctic. We show that this pattern correlates geographically to the spread of prehistoric agriculture and conclude that the diet change may not have been associated with initial domestication but rather the subsequent development and spread of agriculture to most, but not all regions of the globe. PMID:27406651

  6. Patterns of systemic stress during the agricultural transition in prehistoric Japan.

    PubMed

    Temple, Daniel H

    2010-05-01

    This study documents and interprets systemic stress during the agricultural transition in prehistoric Japan using linear enamel hypoplasia (LEH) defects and cribra orbitalia (CO) lesions. Middle to Final Jomon cultures (5000-2300 BP) from Honshu Island represent the foraging samples, while Yayoi cultures (2500-1700 BP) represent the early agricultural samples. Jomon foragers from eastern Japan had broad-based, intensive economies. Jomon foragers from western Japan had a greater focus on seasonally available, nutritionally poor resources, while Yayoi people were descendents of migrants from the East Asian continent and introduced wet rice economies to Japan. This study tests the hypotheses that wet rice economies will be associated with a lower prevalence of teeth/individuals affected by LEH defects in western Japan, while few differences in the prevalence of teeth/individuals with LEH defects will be observed between eastern Jomon people and Yayoi farmers. It is further predicted that similar CO prevalence will be observed between Jomon and Yayoi people given environmental similarities. Significantly greater frequencies of teeth affected by LEH defects are observed among western Jomon compared to Yayoi people. The prevalence of teeth with LEH defects is slightly elevated among eastern Jomon foragers compared to Yayoi agriculturalists. Significant differences in CO prevalence are not observed. Systemic stress prevalence in western Japan likely declined following wet-rice agriculture because this crop provided a predictable, renewable resource base. Systemic stress prevalence was similar between eastern Jomon and Yayoi people because both groups practiced intensive subsistence strategies. Similar CO prevalence reflects infectious diseases associated with living conditions.

  7. Prehistoric Agricultural Communities in West Central Alabama. Volume 2. Studies of Material Remains from the Lubbub Creek Archaeological Locality.

    DTIC Science & Technology

    1983-01-01

    surface only. The exterior aes cf 87.5 percent were burnished, and one sherd, from a flaring rim hibted the cualities of being unburnished and scraped on...picture of health and disease, based on the above features, will be considered in relation to that of comparable prehistoric agricultural populations from...Illinois (Lallo 1973) and the Georgia coast (Larsen 1980). The hypothesized decline in health from Mississippian to Protohistoric times in western

  8. Organic fertilization and sufficient nutrient status in prehistoric agriculture?--Indications from multi-proxy analyses of archaeological topsoil relicts.

    PubMed

    Lauer, Franziska; Prost, Katharina; Gerlach, Renate; Pätzold, Stefan; Wolf, Mareike; Urmersbach, Sarah; Lehndorff, Eva; Eckmeier, Eileen; Amelung, Wulf

    2014-01-01

    Neolithic and Bronze Age topsoil relicts revealed enhanced extractable phosphorus (P) and plant available inorganic P fractions, thus raising the question whether there was targeted soil amelioration in prehistoric times. This study aimed (i) at assessing the overall nutrient status and the soil organic matter content of these arable topsoil relicts, and (ii) at tracing ancient soil fertilizing practices by respective stable isotope and biomarker analyses. Prehistoric arable topsoils were preserved in archaeological pit fillings, whereas adjacent subsoils served as controls. One Early Weichselian humic zone represented the soil status before the introduction of agriculture. Recent topsoils served as an additional reference. The applied multi-proxy approach comprised total P and micronutrient contents, stable N isotope ratios, amino acid, steroid, and black carbon analyses as well as soil color measurements. Total contents of P and selected micronutrients (I, Cu, Mn, Mo, Se, Zn) of the arable soil relicts were above the limits for which nutrient deficiencies could be assumed. All pit fillings exhibited elevated δ15N values close to those of recent topsoils (δ15N>6 to 7‰), giving first hints for prehistoric organic N-input. Ancient legume cultivation as a potential source for N input could not be verified by means of amino acid analysis. In contrast, bile acids as markers for faecal input exhibited larger concentrations in the pit fillings compared with the reference and control soils indicating faeces (i.e. manure) input to Neolithic arable topsoils. Also black carbon contents were elevated, amounting up to 38% of soil organic carbon, therewith explaining the dark soil color in the pit fillings and pointing to inputs of burned biomass. The combination of different geochemical analyses revealed a sufficient nutrient status of prehistoric arable soils, as well as signs of amelioration (inputs of organic material like charcoal and faeces-containing manure).

  9. Organic Fertilization and Sufficient Nutrient Status in Prehistoric Agriculture? – Indications from Multi-Proxy Analyses of Archaeological Topsoil Relicts

    PubMed Central

    Lauer, Franziska; Prost, Katharina; Gerlach, Renate; Pätzold, Stefan; Wolf, Mareike; Urmersbach, Sarah; Lehndorff, Eva; Eckmeier, Eileen; Amelung, Wulf

    2014-01-01

    Neolithic and Bronze Age topsoil relicts revealed enhanced extractable phosphorus (P) and plant available inorganic P fractions, thus raising the question whether there was targeted soil amelioration in prehistoric times. This study aimed (i) at assessing the overall nutrient status and the soil organic matter content of these arable topsoil relicts, and (ii) at tracing ancient soil fertilizing practices by respective stable isotope and biomarker analyses. Prehistoric arable topsoils were preserved in archaeological pit fillings, whereas adjacent subsoils served as controls. One Early Weichselian humic zone represented the soil status before the introduction of agriculture. Recent topsoils served as an additional reference. The applied multi-proxy approach comprised total P and micronutrient contents, stable N isotope ratios, amino acid, steroid, and black carbon analyses as well as soil color measurements. Total contents of P and selected micronutrients (I, Cu, Mn, Mo, Se, Zn) of the arable soil relicts were above the limits for which nutrient deficiencies could be assumed. All pit fillings exhibited elevated δ15N values close to those of recent topsoils (δ15N>6 to 7‰), giving first hints for prehistoric organic N-input. Ancient legume cultivation as a potential source for N input could not be verified by means of amino acid analysis. In contrast, bile acids as markers for faecal input exhibited larger concentrations in the pit fillings compared with the reference and control soils indicating faeces (i.e. manure) input to Neolithic arable topsoils. Also black carbon contents were elevated, amounting up to 38% of soil organic carbon, therewith explaining the dark soil color in the pit fillings and pointing to inputs of burned biomass. The combination of different geochemical analyses revealed a sufficient nutrient status of prehistoric arable soils, as well as signs of amelioration (inputs of organic material like charcoal and faeces-containing manure). PMID

  10. Aspects of health in prehistoric mainland Southeast Asia: Indicators of stress in response to the intensification of rice agriculture.

    PubMed

    Clark, Angela L; Tayles, Nancy; Halcrow, Siân E

    2014-03-01

    Numerous bioarcheological investigations have suggested that as agriculture intensifies, levels of physiological stress and poor health increase. However, previous research in Southeast Asia suggests that a decline in health was not universal. This study aimed to provide the first investigation of human health during the intensification of rice agriculture in the large skeletal sample from the prehistoric site of Ban Non Wat, Northeast Thailand (1750-420 b.c.). Health was analysed using two indicators of childhood stress, the prevalence of linear enamel hypoplasia (LEH), a measure of early childhood stress, and stature, as a measure of late childhood stress, were collated for 190 adults. Sex-specific diachronic relationships between the prevalence of LEH and stature were explored. For both sexes, initially the prevalence of LEH was found to decrease and then increase over time. Stature remained constant over time for males, although for females stature increased initially, then decreased. Early childhood stress was not significantly correlated with stature in females (P = 0.185), but high levels of LEH were unexpectedly correlated with taller male stature (P = 0.017). Our findings suggest an initial improvement in health during agricultural intensification at this site, likely related to a reduction in physiological perturbations and maintenance of a nutritious diet during this time. The subsequent deterioration in health may reflect geomorphologically and archaeologically indicated variation in environmental conditions and consequential sociocultural changes. We suggest that the sex-differences in the relationship between stature and LEH may relate to the timing of stress and/or catch-up growth. Copyright © 2013 Wiley Periodicals, Inc.

  11. The influence of prehistoric Anasazi cobble-mulch agricultural features of northern Rio Grande landscapes

    Treesearch

    Richard D. Periman

    1996-01-01

    Research concerning ancient Pueblo Indian farming, specifically the innovation of cobble-mulch gardens, suggests a manipulation of the local environment on a landscape level that helped create existing ecosystems. This agricultural technology, which consisted of a protective layer of gravel covering the productive soil, trapped seasonal runoff moisture in field areas,...

  12. Prehistoric decline in freshwater mussels coincident with the advent of maize agriculture

    Treesearch

    Evan Peacock; Wendell Haag; Melvin Warren

    2005-01-01

    During late prehistory, high population densities and intensive agricultural practices of Native American societies had profound effects on the pre-Columbian landscape. The degree to which Native American land use affected aquatic ecosystems is unknown. Freshwater mussels are particularly sensitive harbingers of modern-day ecosystem deterioration.We used data from...

  13. Prehistoric Agriculture and Soil Fertility on Lava Flows in Northern Arizona, USA: Results from the San Francisco Volcanic Field REU

    NASA Astrophysics Data System (ADS)

    Broadman, E.; Anderson, K. C.

    2013-12-01

    (Strawberry) soils, suggesting that these nutrients increase over time with eolian deposition and soil development. Results from this study will yield information on the impact of volcanic eruptions and soil development on prehistoric agriculture and soil fertility. This study contributes to our understanding of the interactions between eruptions and human populations.

  14. Sustainable agriculture, soil management and erosion from prehistoric times to 2100

    NASA Astrophysics Data System (ADS)

    Vanwalleghem, Tom; Gómez, Jose Alfonso; Infante Amate, Juan; González Molina, Manuel; Fernández, David Soto; Guzmán, Gema; Vanderlinden, Karl; Laguna, Ana; Giráldez, Juan Vicente

    2015-04-01

    The rational use of soil requires the selection of management practices to take profit of the beneficial functions of plant growth, water and nutrient storage, and pollutants removal by filtering and decomposition without altering its properties. However, the first evidence of important and widespread erosion peaks can generally be found with the arrival of the first farmers all over the world. In areas with a long land-use history such as the Mediterranean, clear signs indicating the advanced degradation status of the landscape, such as heavily truncated soils, are visible throughout. Soil conservation practices are then aimed at reducing erosion to geological rates, in equilibrium with long-term soil formation rates, while maximizing agricultural production. The adoption of such practices in most areas of the world are as old as the earliest soil erosion episodes themselves. This work firstly reviews historical evidence linking soil management and soil erosion intensity, with examples from N Europe and the Mediterranean. In particular, work by the authors in olive orchards will be presented that shows how significant variations in soil erosion rates between could be linked to the historical soil management. The potential of historical documents for calibrating a soil erosion model is shown as the model, in this case RUSLE-based and combining tillage and water erosion, adequately represents the measured erosion rate dynamics. Secondly, results from present-day, long-term farm experiments in the EU are reviewed to evaluate the effect of different soil management practices on physical soil properties, such as bulk density, penetration resistance, aggregate stability, runoff coefficient or sediment yield. Finally, we reflect upon model and field data that indicate how future global climate change is expected to affect soil management and erosion and how the examples used above hold clues about sustainable historical management practices that can be used successfully

  15. Effects of Stratospheric Ozone Depletion the Environment and Agriculture

    NASA Astrophysics Data System (ADS)

    Ali, S. M.; Dash, Nutan Ku; Pradhan, Arjyadhara; Mishra, Sthita Prajna

    2012-09-01

    Ozone depletion results in greater amounts of UV-B radiation that had an impact on terrestrial and aquatic biogeochemical systems. Biogeochemical cycles were the complex interactions of physical, chemical, geological and biological processes that control the transport and transformation of substances in the natural environment and therefore the conditions that humans experience in Earth's system. The increased UV-B radiation impinging on terrestrial and aquatic systems, due to ozone depletion, results in changes in the trace gas exchange between the continents, oceans and the atmosphere. This had result in complex alterations to atmospheric chemistry, the global elemental cycles such as the carbon cycle, and had an impact on the survival and health of all organisms on Earth, including humans.

  16. Has the transition to agriculture reshaped the demographic structure of prehistoric populations? New evidence from the Levant.

    PubMed

    Eshed, Vered; Gopher, Avi; Gage, Timothy B; Hershkovitz, Israel

    2004-08-01

    This paper presents the demographic changes that followed the transition from a hunting-gathering way of life (Natufian) to an agricultural, food-producing economy (Neolithic) in the southern Levant. The study is based on 217 Natufian (10,500-8,300 BC) skeletons and 262 Neolithic (8,300-5,500 BC) skeletons. Age and sex identification were carried out, and life tables were constructed. A five-parameter competing hazard model developed by Siler ([1979] Ecology 60:750-757) was used to smooth life-table data. No indication of increased mortality with the advent of agriculture was noted. On the contrary, both life expectancy at birth (24.6 vs. 25.5 years) and adults' mean age at death (31.2 vs. 32.1 years) increased slightly from the Natufian to the Neolithic period (assuming stationary populations). Yet the transition to agriculture affected males and females differently: mean age at death in the Natufian was higher for adult females compared to adult males, while in the Neolithic, it was the reverse. One interpretation given to the distribution of female ages at death is that with the onset of the Neolithic period, maternal mortality increased as a result of a concomitant increase in fertility. If the adoption of agriculture in the Levant increased the rate of population growth at the beginning of the Neolithic, expectation of life may have increased dramatically.

  17. Prehistorically modified soils of central Amazonia: a model for sustainable agriculture in the twenty-first century.

    PubMed

    Glaser, Bruno

    2007-02-28

    Terra Preta soils of central Amazonia exhibit approximately three times more soil organic matter, nitrogen and phosphorus and 70 times more charcoal compared to adjacent infertile soils. The Terra Preta soils were generated by pre-Columbian native populations by chance or intentionally adding large amounts of charred residues (charcoal), organic wastes, excrements and bones. In this paper, it is argued that generating new Terra Preta sites ('Terra Preta nova') could be the basis for sustainable agriculture in the twenty-first century to produce food for billions of people, and could lead to attaining three Millennium Development Goals: (i) to combat desertification, (ii) to sequester atmospheric CO2 in the long term, and (iii) to maintain biodiversity hotspots such as tropical rainforests. Therefore, large-scale generation and utilization of Terra Preta soils would decrease the pressure on primary forests that are being extensively cleared for agricultural use with only limited fertility and sustainability and, hence, only providing a limited time for cropping. This would maintain biodiversity while mitigating both land degradation and climate change. However, it should not be overlooked that the infertility of most tropical soils (and associated low population density) is what could have prevented tropical forests undergoing large-scale clearance for agriculture. Increased fertility may increase the populations supported by shifting cultivation, thereby maintaining and increasing pressure on forests.

  18. Heat strain, volume depletion and kidney function in California agricultural workers.

    PubMed

    Moyce, Sally; Mitchell, Diane; Armitage, Tracey; Tancredi, Daniel; Joseph, Jill; Schenker, Marc

    2017-06-01

    Agricultural work can expose workers to increased risk of heat strain and volume depletion due to repeated exposures to high ambient temperatures, arduous physical exertion and limited rehydration. These risk factors may result in acute kidney injury (AKI). We estimated AKI cumulative incidence in a convenience sample of 283 agricultural workers based on elevations of serum creatinine between preshift and postshift blood samples. Heat strain was assessed based on changes in core body temperature and heart rate. Volume depletion was assessed using changes in body mass over the work shift. Logistic regression models were used to estimate the associations of AKI with traditional risk factors (age, diabetes, hypertension and history of kidney disease) as well as with occupational risk factors (years in farm work, method of payment and farm task). 35 participants were characterised with incident AKI over the course of a work shift (12.3%). Workers who experienced heat strain had increased adjusted odds of AKI (1.34, 95% CI 1.04 to 1.74). Piece rate work was associated with 4.24 odds of AKI (95% CI 1.56 to 11.52). Females paid by the piece had 102.81 adjusted odds of AKI (95% CI 7.32 to 1443.20). Heat strain and piece rate work are associated with incident AKI after a single shift of agricultural work, though gender differences exist. Modifications to payment structures may help prevent AKI. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  19. Monsoon Harvests: The Socio-Ecohydrology of Agricultural Rainwater Harvesting and Groundwater Depletion in India

    NASA Astrophysics Data System (ADS)

    Basu, N. B.; Hora, T.; Van Meter, K. J.

    2016-12-01

    Rainwater harvesting (RWH), the small-scale collection and storage of runoff for irrigated agriculture, is recognized as a sustainable strategy for ensuring food security, especially in monsoonal landscapes in the developing world. In south India, these strategies have been used for millennia to mitigate problems of water scarcity. However, in the past 100 years many traditional RWH systems have fallen into disrepair due to increasing dependence on groundwater. This dependence has contributed to an accelerated decline in groundwater resources, which has in turn led to increased efforts at the state and national levels to revive older RWH systems. Critical to the success of such efforts is an improved understanding of how these ancient systems function in contemporary landscapes with extensive groundwater pumping and shifted climatic regimes. Here, we use a combination of data analyses and modeling to quantify the coupled natural and human controls on the spatiotemporal trajectories of groundwater depletion and rainwater harvesting in monsoonal India.

  20. Digging into Prehistoric Iowa.

    ERIC Educational Resources Information Center

    Swaim, Ginalie, Ed.

    1985-01-01

    A theme issue of the Iowa State Historical Department magazine focuses on elementary readings and activities about prehistoric Iowa. The issue contains a total of 16 articles. In "History Makers," a ten-year-old recounts his family's discovery of a mammoth bone on their farm. "Imagine a Camping Trip Long Ago" looks at how the…

  1. Symbolism in prehistoric man.

    PubMed

    Facchini, F

    2000-12-01

    The aptitude for symbolization, characteristic of man, is revealed not only in artistic representations and funerary practices. It is exhibited by every manifestation of human activity or representation of natural phenomena that assumes or refers to a meaning. We can recognize functional symbolism (tool-making, habitative or food technology), social symbolism, (language and social communication) and spiritual symbolism (funerary practices and artistic expressions). On the basis of these concepts, research into symbolism in prehistoric man allows us to recognize forms of symbolism already in the manifestations of the most ancient humans, starting with Homo habilis (or rudolfensis). Toolmaking, social organization and organization of the territory are oriented toward survival and the life of the family group. They attest to symbolic behaviors and constitute symbolic systems by means of which man expresses himself, lives and transmits his symbolic world. The diverse forms of symbolism are discussed with reference to the different phases of prehistoric humanity.

  2. Prehistoric New Zealanders.

    PubMed

    Houghton, P

    1978-03-22

    The physical condition of prehistoric man in New Zealand is briefly surveyed. These were tall, robust Polynesian people living an active existence, and having an adequate diet. The mean life span of about 30 years for adults was short only by modern Western standards. A number of skeletal features, notably aspects of skull and long bone form, set them apart from other races of mankind.

  3. Prehistoric human colonization of India.

    PubMed

    Misra, V N

    2001-11-01

    Human colonization in India encompasses a span of at least half-a-million years and is divided into two broad periods, namely the prehistoric (before the emergence of writing) and the historic (after writing). The prehistoric period is divided into stone, bronze and iron ages. The stone age is further divided into palaeolithic, mesolithic and neolithic periods. As the name suggests, the technology in these periods was primarily based on stone. Economically, the palaeolithic and mesolithic periods represented a nomadic, hunting-gathering way of life, while the neolithic period represented a settled, food-producing way of life. Subsequently copper was introduced as a new material and this period was designated as the chalcolithic period. The invention of agriculture, which took place about 8000 years ago, brought about dramatic changes in the economy, technology and demography of human societies. Human habitat in the hunting-gathering stage was essentially on hilly, rocky and forested regions, which had ample wild plant and animal food resources. The introduction of agriculture saw it shifting to the alluvial plains which had fertile soil and perennial availability of water. Hills and forests, which had so far been areas of attraction, now turned into areas of isolation. Agriculture led to the emergence of villages and towns and brought with it the division of society into occupational groups. The first urbanization took place during the bronze age in the arid and semi-arid region of northwest India in the valleys of the Indus and the Saraswati rivers, the latter represented by the now dry Ghaggar-Hakra bed. This urbanization is known as the Indus or Harappan civilization which flourished during 3500-1500 B.C. The rest of India during this period was inhabited by neolithic and chalcolithic farmers and mesolithic hunter-gatherers. With the introduction of iron technology about 3000 years ago, the focus of development shifted eastward into the Indo-Gangetic divide and

  4. Agricultural land-use change in a Mexican oligotrophic desert depletes ecosystem stability

    PubMed Central

    Hernández-Becerra, Natali; Tapia-Torres, Yunuen; Beltrán-Paz, Ofelia; Blaz, Jazmín; Souza, Valeria

    2016-01-01

    Background Global demand for food has led to increased land-use change, particularly in dry land ecosystems, which has caused several environmental problems due to the soil degradation. In the Cuatro Cienegas Basin (CCB), alfalfa production irrigated by flooding impacts strongly on the soil. Methods In order to analyze the effect of such agricultural land-use change on soil nutrient dynamics and soil bacterial community composition, this work examined an agricultural gradient within the CCB which was comprised of a native desert grassland, a plot currently cultivated with alfalfa and a former agricultural field that had been abandoned for over 30 years. For each site, we analyzed C, N and P dynamic fractions, the activity of the enzyme phosphatase and the bacterial composition obtained using 16S rRNA clone libraries. Results The results showed that the cultivated site presented a greater availability of water and dissolved organic carbon, these conditions promoted mineralization processes mediated by heterotrophic microorganisms, while the abandoned land was limited by water and dissolved organic nitrogen. The low amount of dissolved organic matter promoted nitrification, which is mediated by autotrophic microorganisms. The microbial N immobilization process and specific phosphatase activity were both favored in the native grassland. As expected, differences in bacterial taxonomical composition were observed among sites. The abandoned site exhibited similar compositions than native grassland, while the cultivated site differed. Discussion The results suggest that the transformation of native grassland into agricultural land induces drastic changes in soil nutrient dynamics as well as in the bacterial community. However, with the absence of agricultural practices, some of the soil characteristics analyzed slowly recovers their natural state. PMID:27602304

  5. Agricultural land-use change in a Mexican oligotrophic desert depletes ecosystem stability.

    PubMed

    Hernández-Becerra, Natali; Tapia-Torres, Yunuen; Beltrán-Paz, Ofelia; Blaz, Jazmín; Souza, Valeria; García-Oliva, Felipe

    2016-01-01

    Global demand for food has led to increased land-use change, particularly in dry land ecosystems, which has caused several environmental problems due to the soil degradation. In the Cuatro Cienegas Basin (CCB), alfalfa production irrigated by flooding impacts strongly on the soil. In order to analyze the effect of such agricultural land-use change on soil nutrient dynamics and soil bacterial community composition, this work examined an agricultural gradient within the CCB which was comprised of a native desert grassland, a plot currently cultivated with alfalfa and a former agricultural field that had been abandoned for over 30 years. For each site, we analyzed C, N and P dynamic fractions, the activity of the enzyme phosphatase and the bacterial composition obtained using 16S rRNA clone libraries. The results showed that the cultivated site presented a greater availability of water and dissolved organic carbon, these conditions promoted mineralization processes mediated by heterotrophic microorganisms, while the abandoned land was limited by water and dissolved organic nitrogen. The low amount of dissolved organic matter promoted nitrification, which is mediated by autotrophic microorganisms. The microbial N immobilization process and specific phosphatase activity were both favored in the native grassland. As expected, differences in bacterial taxonomical composition were observed among sites. The abandoned site exhibited similar compositions than native grassland, while the cultivated site differed. The results suggest that the transformation of native grassland into agricultural land induces drastic changes in soil nutrient dynamics as well as in the bacterial community. However, with the absence of agricultural practices, some of the soil characteristics analyzed slowly recovers their natural state.

  6. Quaternary stratigraphy and tectonics, and late prehistoric agriculture of the Safford Basin (Gila and San Simon river valleys), Graham County, Arizona

    USGS Publications Warehouse

    Houser, Brenda B.; Pearthree, Phillip A.; Homburg, Jeffry A.; Thrasher, Lawrence C.

    2004-01-01

    This guidebook accompanied the 46th annual meeting of the Rocky Mountain Cell of the Friends of the Pleistocene (FOP) and the 2002 Fall Field Trip of the Arizona Geological Society. The meeting and field trip were held in the Safford Basin, southeastern Arizona. The Friends of the Pleistocene is an informal gathering of Quaternary geologists, geomorphologists, and pedologists who meet annually for a field conference. The first part of the guidebook consists of road logs with descriptions of stops covering the three days of the field trip. An overview of the geology of the Safford Basin is given in Stop 1-1. The second part of the guidebook consists of four short papers that discuss adjacent areas or that expand upon the road log descriptions of the field trip stops. The first paper by Reid and Buffler is a summary of upper Cenozoic depositional facies in the Duncan Basin, the first basin to the east of the Safford Basin. The next three papers expand upon (1) the soil study of the gridded field agricultural complex (Stop 2-3, Homburg and Sandor), (2) the vertebrate fossils of the San Simon Valley in the southeastern part of the Safford Basin (Stop 3-1, Thrasher), and (3) paleoIndian irrigation systems and settlements in Lefthand Canyon at the foot of the Pinaleno Mountains (Stop 3-2, Neely and Homburg).

  7. From ozone depletion to agriculture: understanding the role of UV radiation in sustainable crop production.

    PubMed

    Wargent, Jason J; Jordan, Brian R

    2013-03-01

    Largely because of concerns regarding global climate change, there is a burgeoning interest in the application of fundamental scientific knowledge in order to better exploit environmental cues in the achievement of desirable endpoints in crop production. Ultraviolet (UV) radiation is an energetic driver of a diverse range of plant responses and, despite historical concerns regarding the damaging consequences of UV-B radiation for global plant productivity as related to stratospheric ozone depletion, current developments representative of a range of organizational scales suggest that key plant responses to UV-B radiation may be exploitable in the context of a sustainable contribution towards the strengthening of global crop production, including alterations in secondary metabolism, enhanced photoprotection, up-regulation of the antioxidative response and modified resistance to pest and disease attack. Here, we discuss the prospect of this paradigm shift in photobiology, and consider the linkages between fundamental plant biology and crop-level outcomes that can be applied to the plant UV-B response, in addition to the consequences for related biota and many other facets of agro-ecosystem processes. © 2013 The Author. New Phytologist © 2012 New Phytologist Trust.

  8. [Spiritual manifestations in prehistoric images].

    PubMed

    Kolmer, H

    1975-01-01

    Having visited the places of prehistoric cult and cave paintings of the Franco-Cantabrian region, central Sahara, Monte Bego and Val Camonica as well as Switzerland and Austria, the author attempts to outline a chronological profile of the occidental prehistoric art. The evolution is marked by a progressive extension of the mental horizon and of the ability to abstract, the emergence of a more analytical and composed way of thinking, the development of an anesthetic representation power which no doubt were the basis of the invention of writing.

  9. Prehistoric astronomy in the Southwest.

    NASA Astrophysics Data System (ADS)

    McK. Malville, J.; Putnam, C.

    Many sites in the southwestern United States have yielded evidence of the prehistoric Anasazi's intense interest in astronomy, similar to that of the megalithic cultures of Europe. The authors describe the astronomical alignments at the well-known sites of Chaco Canyon and Hovenweep and present new evidence, based on recent field work of alignments at Yellow Jacket and Chimney Rock. Drawing on the archeological evidence, ethnographical parallels with historic pueblo peoples, and mythology from other cultures, the authors present theories about the meaning and function of the mysterious stone alignments and architectural orientations of the prehistoric Southwest.

  10. Prehistoric Astronomy in China

    NASA Astrophysics Data System (ADS)

    Chiu, B. C.

    2000-05-01

    We do not have definite proof, but the situation is very interesting, so here is a summary of what we have from calculations and literature research. The ancient Classics of China were written in an archaic, terse language. But the philologist, Bernhard Karlgren, was able to argue that the constellations, (Niao, Huo, Hsu, Mao) were what the oldest stories referred to when the Sage Yao gave directions for agriculture by use of astronomy. Huo and Mao are now well-identified as the asterisms, Antares and the Pleiades. And using tables of precession, which we now have, we find that the text gives a date thousands of years earlier than previously thought. Together with results from studies in prehistory in the last two decades, we can form a plausible picture of how the Pleiades, and then Antares were observed, telling of the beginning of warming, and then the beginning of harvest. We have had at least two obstacles to overcome: one, we had to show the stories were written earlier than one thousand years ago because the Chinese knew of precession then and could have made up the story. Secondly, that the `culmination' written about by Joseph Needham probably referred to a much later time.

  11. Dental enamel hypoplasias in prehistoric populations.

    PubMed

    Goodman, A H

    1989-09-01

    Recent years have witnessed an impressive increase in research on enamel hypoplasias in archaeological populations. By reviewing a series of studies of enamel hypoplasias at Dickson Mounds, Illinois, North America (950-1300 A.D.), a prehistoric site involved in the transition from gathering-hunting to agriculture, this paper provides an illustration of this type of research. The location of linear hypoplasias on labial tooth surfaces of 111 adults was studied with a thin-tipped caliper, and this location was converted to an age at development. Most defects developed between two and four years of developmental age. Hypoplasias increased in prevalence from 45% in the pre-agriculture group to 80% in the agricultural group (p less than 0.01). The transition to agriculture occurred at a cost to infant and childhood health. Defects are associated with decreased longevity. Individuals with defects have a life expectancy of nearly ten years fewer than those without defects, suggesting that the development of a defect marks a significant and lasting health event. Enamel hypoplasias occur most frequently on anterior teeth, polar teeth in developmental fields, and the middle developmental thirds of teeth. Analysis of these data suggests that enamel may be differentially susceptible to growth disruption and that susceptibility varies both within and among teeth. The study of enamel defects at Dickson provides insights into the health and nutritional consequences of the economic change from hunting and gathering to agriculture. More generally, with the availability of teeth from genetically homogeneous populations, studies of enamel hypoplasias in prehistory should provide a useful complement to research on this condition in contemporary peoples.

  12. Integrating GRACE and multi-source data sets to quantify the seasonal groundwater depletion in mega agricultural regions

    NASA Astrophysics Data System (ADS)

    Tang, Y.; Wang, D.; Zhu, T.; Ringler, C.; Sun, A. Y.

    2015-12-01

    It is challenging to quantify the groundwater depletion in the mega basins owing to the huge spatial scale and the intensive anthrophonic activities (e.g. dams and reservoirs). Recently, the satellite Gravity Recovery and Climate Experiment (GRACE) data provides an opportunity to monitor large-scale groundwater depletion. However, the data is only available after 2002, limiting the understanding of inter-annual variability of seasonal groundwater depletion. In this study, a simple model with two parameters is developed, based on the seasonal Budyko framework for quantifying the seasonal groundwater depletion. The model is applied to the Indus and Ganges River basin in South Asia and the High Plain/Ogallala aquifer in United States. The parameters of the model are estimated by integrating GRACE and other multi-source data sets. Total water storage changes before 2003 are reconstructed based on the developed model with available data of evaporation, precipitation, and potential evaporation.

  13. Modeling the prehistoric Maori population.

    PubMed

    Brewis, A A; Molloy, M A; Sutton, D G

    1990-03-01

    Skeletal and comparative evidence of mortality is combined with fertility estimates for the precontact Maori population of New Zealand to determine the implied rate of precontact population growth. This rate is found to be too low to populate New Zealand within the time constraints of its prehistoric sequence, the probable founding population size, and the probable population size at contact. Rates of growth necessary to populate New Zealand within the accepted time span are calculated. The differences between this minimum necessary rate and the skeletally derived rate are too large to result solely from inadequacies in the primary data. Four alternative explanations of this conundrum are proposed: 1) skeletal evidence of precontact mortality is highly inaccurate; 2) skeletal evidence of fertility is severely underestimating actual levels; 3) there was very rapid population growth in the earliest part of the sequence up to 1150 A.D., from which no skeletal evidence currently is available; or 4) the prehistoric sequence of New Zealand may have been longer than the generally accepted 1,000-1,200 years. These alternatives are examined, and a combination of the last two is found to be the most probable. The implications of this model for New Zealand prehistory and Oceanic paleodemography are discussed.

  14. Prehistoric human settling on the Tibetan Plateau

    NASA Astrophysics Data System (ADS)

    Chen, Fahu; Zhang, Dongju; Dong, Guanghui

    2017-04-01

    When and where did human first settle down on the Tibetan Plateau is under hot debate among archaeologist, anthropologists, geneticist and paleo-geographers. Based on systematic archaeological, chronological and archaeo-botanical studies of 53 sites in Northeastern Tibetan Plateau, we propose that agriculture facilitated human permanent settlement on the Tibetan Plateau initially since 5200 years ago below 2500 masl and since 3600 years ago up to around 4000 masl, possibly assisted by domesticated animals (Chen et al. 2015). By studying hand- and footprints in Chusang, Meyer et al. (2016) argue that hunter-gatherers permanently occupied central Tibetan Plateau in early Holocene without the help of agriculture. However, we think the limited hand- and footprints evidence found in Chusang could indicate no more than prehistoric hunter-gatherers presence on the remote central Tibetan Plateau in the early Holocene. In addition, by reviewing all the published archaeological data, we propose that human migrated to the Tibetan Plateau from the last Deglacial period to late Holocene mainly from North China via Yellow River valley and its tributary valleys in the Northeastern Tibetan Plateau (NETP). This migration is constituted of four stages (Upper Paleolithic, Epi-Paleolithic, Neolithic and Bronze Age) when human adapted to the high altitude environment and climate change with different strategies and techniques. Particularly, the prevail of microlithic technology in North China provoked hunter-gatherers' first visit to the NETP in relatively ameliorated last Deglacial period, and the the quick development of millet farming and subsequent mixed barley-wheat farming and sheep herding facilitated farmers and herders permanently settled in Tibetan Plateau, even above 3000 masl, during mid- and late Holocene. References: Chen et al., 2015. Agriculture facilitated permanent human occupation of the Tibetan Plateau after 3600 BP. Science, 347: 248-250. Meyer et al., 2016

  15. Evidence of size-selective evolution in the fighting conch from prehistoric subsistence harvesting.

    PubMed

    O'Dea, Aaron; Shaffer, Marian Lynne; Doughty, Douglas R; Wake, Thomas A; Rodriguez, Felix A

    2014-05-07

    Intensive size-selective harvesting can drive evolution of sexual maturity at smaller body size. Conversely, prehistoric, low-intensity subsistence harvesting is not considered an effective agent of size-selective evolution. Uniting archaeological, palaeontological and contemporary material, we show that size at sexual maturity in the edible conch Strombus pugilis declined significantly from pre-human (approx. 7 ka) to prehistoric times (approx. 1 ka) and again to the present day. Size at maturity also fell from early- to late-prehistoric periods, synchronous with an increase in harvesting intensity as other resources became depleted. A consequence of declining size at maturity is that early prehistoric harvesters would have received two-thirds more meat per conch than contemporary harvesters. After exploring the potential effects of selection biases, demographic shifts, environmental change and habitat alteration, these observations collectively implicate prehistoric subsistence harvesting as an agent of size-selective evolution with long-term detrimental consequences. We observe that contemporary populations that are protected from harvesting are slightly larger at maturity, suggesting that halting or even reversing thousands of years of size-selective evolution may be possible.

  16. Evidence of size-selective evolution in the fighting conch from prehistoric subsistence harvesting

    PubMed Central

    O'Dea, Aaron; Shaffer, Marian Lynne; Doughty, Douglas R.; Wake, Thomas A.; Rodriguez, Felix A.

    2014-01-01

    Intensive size-selective harvesting can drive evolution of sexual maturity at smaller body size. Conversely, prehistoric, low-intensity subsistence harvesting is not considered an effective agent of size-selective evolution. Uniting archaeological, palaeontological and contemporary material, we show that size at sexual maturity in the edible conch Strombus pugilis declined significantly from pre-human (approx. 7 ka) to prehistoric times (approx. 1 ka) and again to the present day. Size at maturity also fell from early- to late-prehistoric periods, synchronous with an increase in harvesting intensity as other resources became depleted. A consequence of declining size at maturity is that early prehistoric harvesters would have received two-thirds more meat per conch than contemporary harvesters. After exploring the potential effects of selection biases, demographic shifts, environmental change and habitat alteration, these observations collectively implicate prehistoric subsistence harvesting as an agent of size-selective evolution with long-term detrimental consequences. We observe that contemporary populations that are protected from harvesting are slightly larger at maturity, suggesting that halting or even reversing thousands of years of size-selective evolution may be possible. PMID:24648229

  17. Agro-Forestry system in West Africa: integrating a green solution to cope with soil depletion towards agricultural sustainability

    NASA Astrophysics Data System (ADS)

    Monteiro, Filipa; Vidigal, Patricia; Romeiras, Maria Manuel; Ribeiro, Ana; Abreu, Maria Manuela; Viegas, Wanda; Catarino, Luís

    2017-04-01

    During the last decades, agriculture in West Africa has been marked by dramatic shifts with the coverage of single crops, increasing pressure over the available arable land. Yet, West African countries are still striving to achieve sustainable production at an increased scale for global market needs. Market-driven rapid intensification is often a major cause for cropland area expansion at the expense of deforestation and soil degradation, especially to export commodities in times of high prices. Cashew (Anacardium occidentale L.) is nowadays an important export-oriented crop, being produced under intensive cultivation regimes in several tropical regions. Particularly, among the main cashew production areas, West Africa is the most recent and dynamic in the world, accounting for 45% of the world cashew nuts production in 2015. Considering its global market values, several developing countries rely on cashew nuts as national economy revenues, namely in Guinea-Bissau. Considering the intensive regime of cashew production in Guinea-Bissau, and as widely recognized, intensive agriculture linked with extensification can negatively impact ecosystems, affecting natural resources availability, soil erosion and arability compromised by excessive salinity. Ultimately this will result in the disruption of carbon - nitrogen cycle, important to the agricultural ecosystem sustainability. As such, tree intercropped with legumes as cover crops, offers a sustainable management of the land area, thus creating substantial benefits both economically and environmentally, as it enhances diversification of products outputs and proving to be more sustainable than forestry and/or agricultural monocultures. Soil fertility improvement is a key entry point for achieving food security, and also increment agriculture commodities of the agro-system. Without using inorganic fertilizers, the green solution for improving soil management is to incorporate adapted multi-purpose legumes as cover crops

  18. Fire effects on prehistoric ceramics [Chapter 3

    Treesearch

    Trisha Rude; Anne Trinkle Jones

    2012-01-01

    In North America, prehistoric pottery is primarily earthenware (a porous ceramic, fired at a relatively low temperature). It is not glass-like or dense like other kinds of pottery such as stoneware and porcelain (see chapter 6).

  19. Aspects of prehistoric astronomy in India

    NASA Astrophysics Data System (ADS)

    Rao, N. Kameswara

    2005-12-01

    Some archeoastronomical aspects regarding the development of observational astronomy in India during prehistoric times are described. A plea is made for the preservation of megalithic monuments of possible astronomical significance.

  20. Agriculture

    EPA Pesticide Factsheets

    The EPA Agriculture Resource Directory offers comprehensive, easy-to-understand information about environmental stewardship on farms and ranches; commonsense, flexible approaches that are both environmentally protective and agriculturally sound.

  1. Stable nitrogen isotope ratios of bone collagen reflect marine and terrestrial components of prehistoric human diet

    SciTech Connect

    Schoeninger, M.J.; DeNiro, M.J.; Tauber, H.

    1983-06-24

    delta/sup 15/N values of bone collagen from Eskimos and from Northwst Coast Indians dependent on salmon fishing are about 10 per mil more positive than those from agriculturalists in historic times. Among prehistoric humans, two groups dependent on marine food sources show bone collagen delta/sup 15/N values that are 4 to 6 per mil more positive than those from two agricultural groups. The nitrogen isotope ratios of bone collagen from prehistoric inhabitants of Bahamas are anomalously low for reasons that relate to the biogeochemical cycle of nitrogen in coral reefs.

  2. The Path towards Endangered Species: Prehistoric Fisheries in Southeastern Brazil

    PubMed Central

    Lopes, Mariana Samôr; Bertucci, Thayse Cristina Pereira; Rapagnã, Luciano; Tubino, Rafael de Almeida; Monteiro-Neto, Cassiano; Tomas, Acácio Ribeiro Gomes; Tenório, Maria Cristina; Lima, Tânia; Souza, Rosa; Carrillo-Briceño, Jorge Domingo; Haimovici, Manuel; Macario, Kita; Carvalho, Carla; Aguilera Socorro, Orangel

    2016-01-01

    Brazilian shellmounds are archaeological sites with a high concentration of marine faunal remains. There are more than 2000 sites along the coast of Brazil that range in age from 8,720 to 985 cal BP. Here, we studied the ichthyoarchaeological remains (i.e., cranial/postcranial bones, otoliths, and teeth, among others) at 13 shellmounds on the southern coast of the state of Rio de Janeiro, which are located in coastal landscapes, including a sandy plain with coastal lagoons, rocky islands, islets and rocky bays. We identified patterns of similarity between shellmounds based on fish diversity, the ages of the assemblages, littoral geomorphology and prehistoric fisheries. Our new radiocarbon dating, based on otolith samples, was used for fishery characterization over time. A taxonomical study of the ichthyoarchaeological remains includes a diversity of 97 marine species, representing 37% of all modern species (i.e., 265 spp.) that have been documented along the coast of Rio de Janeiro state. This high fish diversity recovered from the shellmounds is clear evidence of well-developed prehistoric fishery activity that targeted sharks, rays and finfishes in a productive area influenced by coastal marine upwelling. The presence of adult and neonate shark, especially oceanic species, is here interpreted as evidence of prehistoric fisheries capacity for exploitation and possibly overexploitation in nursery areas. Various tools and strategies were used to capture finfish in seasonal fisheries, over rocky reef bottoms and in sandy littoral environments. Massive catches of whitemouth croaker, main target dermersal species of South Atlantic coast, show evidence of a reduction in body size of approximately 28% compared with modern fisheries. Fishery activity involving vulnerable species, especially in nursery areas, could mark the beginning of fish depletion along the southeastern Brazilian coast and the collapse of natural fish populations. PMID:27355355

  3. The Path towards Endangered Species: Prehistoric Fisheries in Southeastern Brazil.

    PubMed

    Lopes, Mariana Samôr; Bertucci, Thayse Cristina Pereira; Rapagnã, Luciano; Tubino, Rafael de Almeida; Monteiro-Neto, Cassiano; Tomas, Acácio Ribeiro Gomes; Tenório, Maria Cristina; Lima, Tânia; Souza, Rosa; Carrillo-Briceño, Jorge Domingo; Haimovici, Manuel; Macario, Kita; Carvalho, Carla; Aguilera Socorro, Orangel

    2016-01-01

    Brazilian shellmounds are archaeological sites with a high concentration of marine faunal remains. There are more than 2000 sites along the coast of Brazil that range in age from 8,720 to 985 cal BP. Here, we studied the ichthyoarchaeological remains (i.e., cranial/postcranial bones, otoliths, and teeth, among others) at 13 shellmounds on the southern coast of the state of Rio de Janeiro, which are located in coastal landscapes, including a sandy plain with coastal lagoons, rocky islands, islets and rocky bays. We identified patterns of similarity between shellmounds based on fish diversity, the ages of the assemblages, littoral geomorphology and prehistoric fisheries. Our new radiocarbon dating, based on otolith samples, was used for fishery characterization over time. A taxonomical study of the ichthyoarchaeological remains includes a diversity of 97 marine species, representing 37% of all modern species (i.e., 265 spp.) that have been documented along the coast of Rio de Janeiro state. This high fish diversity recovered from the shellmounds is clear evidence of well-developed prehistoric fishery activity that targeted sharks, rays and finfishes in a productive area influenced by coastal marine upwelling. The presence of adult and neonate shark, especially oceanic species, is here interpreted as evidence of prehistoric fisheries capacity for exploitation and possibly overexploitation in nursery areas. Various tools and strategies were used to capture finfish in seasonal fisheries, over rocky reef bottoms and in sandy littoral environments. Massive catches of whitemouth croaker, main target dermersal species of South Atlantic coast, show evidence of a reduction in body size of approximately 28% compared with modern fisheries. Fishery activity involving vulnerable species, especially in nursery areas, could mark the beginning of fish depletion along the southeastern Brazilian coast and the collapse of natural fish populations.

  4. Anthropocene rockfalls travel farther than prehistoric predecessors.

    PubMed

    Borella, Josh Walter; Quigley, Mark; Vick, Louise

    2016-09-01

    Human modification of natural landscapes has influenced surface processes in many settings on Earth. Quantitative data comparing the distribution and behavior of geologic phenomena before and after human arrival are sparse but urgently required to evaluate possible anthropogenic influences on geologic hazards. We conduct field and imagery-based mapping, statistical analysis, and numerical modeling of rockfall boulders triggered by the fatal 2011 Christchurch earthquakes (n = 285) and newly identified prehistoric (Holocene and Pleistocene) boulders (n = 1049). Prehistoric and modern boulders are lithologically equivalent, derived from the same source cliff, and yield consistent power-law frequency-volume distributions. However, a significant population of modern boulders (n = 26) traveled farther downslope (>150 m) than their most-traveled prehistoric counterparts, causing extensive damage to residential dwellings at the foot of the hillslope. Replication of prehistoric boulder distributions using three-dimensional rigid-body numerical models that incorporate lidar-derived digital topography and realistic boulder trajectories and volumes requires the application of a drag coefficient, attributed to moderate to dense slope vegetation, to account for their spatial distribution. Incorporating a spatially variable native forest into the models successfully predicts prehistoric rockfall distributions. Radiocarbon dating provides evidence for 17th to early 20th century deforestation at the study site during Polynesian and European colonization and after emplacement of prehistoric rockfall. Anthropocene deforestation enabled modern rockfalls to exceed the limits of their prehistoric predecessors, highlighting a shift in the geologic expression of rockfalls due to anthropogenic activity. Reforestation of hillslopes by mature native vegetation could help reduce future rockfall hazard.

  5. Anthropocene rockfalls travel farther than prehistoric predecessors

    PubMed Central

    Borella, Josh Walter; Quigley, Mark; Vick, Louise

    2016-01-01

    Human modification of natural landscapes has influenced surface processes in many settings on Earth. Quantitative data comparing the distribution and behavior of geologic phenomena before and after human arrival are sparse but urgently required to evaluate possible anthropogenic influences on geologic hazards. We conduct field and imagery-based mapping, statistical analysis, and numerical modeling of rockfall boulders triggered by the fatal 2011 Christchurch earthquakes (n = 285) and newly identified prehistoric (Holocene and Pleistocene) boulders (n = 1049). Prehistoric and modern boulders are lithologically equivalent, derived from the same source cliff, and yield consistent power-law frequency-volume distributions. However, a significant population of modern boulders (n = 26) traveled farther downslope (>150 m) than their most-traveled prehistoric counterparts, causing extensive damage to residential dwellings at the foot of the hillslope. Replication of prehistoric boulder distributions using three-dimensional rigid-body numerical models that incorporate lidar-derived digital topography and realistic boulder trajectories and volumes requires the application of a drag coefficient, attributed to moderate to dense slope vegetation, to account for their spatial distribution. Incorporating a spatially variable native forest into the models successfully predicts prehistoric rockfall distributions. Radiocarbon dating provides evidence for 17th to early 20th century deforestation at the study site during Polynesian and European colonization and after emplacement of prehistoric rockfall. Anthropocene deforestation enabled modern rockfalls to exceed the limits of their prehistoric predecessors, highlighting a shift in the geologic expression of rockfalls due to anthropogenic activity. Reforestation of hillslopes by mature native vegetation could help reduce future rockfall hazard. PMID:27652344

  6. The Influence of Groundwater Depletion from Irrigated Agriculture on the Tradeoffs between Ecosystem Services and Economic Returns

    PubMed Central

    Kovacs, Kent; West, Grant

    2016-01-01

    An irrigated agricultural landscape experiencing groundwater overdraft generates economic returns and a suite of ecosystem services (in particular, groundwater supply, greenhouse gases reduction, and surface water quality). Alternative land cover choices indicate tradeoffs among the value of ecosystem services created and the economic returns. These tradeoffs are explored using efficiency frontiers that determine the least value in ecosystem services that must be given up to generate additional economic returns. Agricultural producers may switch to irrigation with surface water using on-farm reservoirs and tail water recovery systems in response to groundwater overdraft, and this has consequences for the bundle of ecosystem service values and economic returns achievable from the landscape. Planning that accounts for both ecosystem service value and economic returns can achieve more value for society, as does the adoption of reservoirs though lowering the costs of irrigation, increasing groundwater levels, and reducing fuel combustion and associated GHG emissions from groundwater pumping. Sensitivity analyses of per unit value of ecosystem services, crop prices, and the groundwater and water purification model parameters indicate tradeoff among ecosystems service values, such as the use of a high-end social cost of carbon ultimately lowers groundwater supply and water purification value by more than 15%. PMID:28033405

  7. The Influence of Groundwater Depletion from Irrigated Agriculture on the Tradeoffs between Ecosystem Services and Economic Returns.

    PubMed

    Kovacs, Kent; West, Grant

    2016-01-01

    An irrigated agricultural landscape experiencing groundwater overdraft generates economic returns and a suite of ecosystem services (in particular, groundwater supply, greenhouse gases reduction, and surface water quality). Alternative land cover choices indicate tradeoffs among the value of ecosystem services created and the economic returns. These tradeoffs are explored using efficiency frontiers that determine the least value in ecosystem services that must be given up to generate additional economic returns. Agricultural producers may switch to irrigation with surface water using on-farm reservoirs and tail water recovery systems in response to groundwater overdraft, and this has consequences for the bundle of ecosystem service values and economic returns achievable from the landscape. Planning that accounts for both ecosystem service value and economic returns can achieve more value for society, as does the adoption of reservoirs though lowering the costs of irrigation, increasing groundwater levels, and reducing fuel combustion and associated GHG emissions from groundwater pumping. Sensitivity analyses of per unit value of ecosystem services, crop prices, and the groundwater and water purification model parameters indicate tradeoff among ecosystems service values, such as the use of a high-end social cost of carbon ultimately lowers groundwater supply and water purification value by more than 15%.

  8. Prehistoric bird extinctions and human hunting.

    PubMed

    Duncan, Richard P; Blackburn, Tim M; Worthy, Trevor H

    2002-03-07

    Holocene fossils document the extinction of hundreds of bird species on Pacific islands during prehistoric human occupation. Human hunting is implicated in these extinctions, but the impact of hunting is difficult to disentangle from the effects of other changes induced by humans, including habitat destruction and the introduction of other mammalian predators. Here, we use data from bones collected at a natural sand dune site and associated archaeological middens in New Zealand to show that, having controlled for differences in body mass and family membership (and hence for variation in life-history traits related to population growth rate), birds that were more intensively hunted by prehistoric humans had a higher probability of extinction. This result cannot be attributed to preservation biases and provides clear evidence that selective hunting contributed significantly to prehistoric bird extinctions at this site.

  9. Mythological and Prehistorical Origins of Neurosurgery.

    PubMed

    Nanda, Anil; Filis, Andreas; Kalakoti, Piyush

    2016-05-01

    Mythology has a cultural appeal, and the description of some neurosurgical procedures in the Hindu, Greek, Egyptian, and Chinese mythology has a bearing to the origins of our professions. The traces to some of our modern-day practices also can be linked back to the ancient prehistoric eras of the Siberian, Persian, and the Andean region. In this historical perspective, we briefly dwell into individual accounts through the prism of different cultures to highlight the development of neurosurgery in mythology and prehistoric era.

  10. Prehistoric Phenomena and Self-referentiality

    NASA Astrophysics Data System (ADS)

    Yu, Junhua

    By terms-allowed-in-types capacity, the Logic of Proofs LP enjoys a system of advanced combinatory terms, while including types of the form t:φ(t), which have self-referential meanings. This paper suggests a research on possible S4 measures of self-referentiality introduced by this capacity. Specifically, we define "prehistoric phenomena" in G3s, a Gentzen-style formulation of modal logic S4. A special phenomenon, namely, "left prehistoric loop", is then shown to be necessary for self-referentiality in realizations of S4 theorems in LP.

  11. The evolution of social behavior in the prehistoric American southwest.

    PubMed

    Gumerman, George J; Swedlund, Alan C; Dean, Jeffrey S; Epstein, Joshua M

    2003-01-01

    Long House Valley, located in the Black Mesa area of northeastern Arizona (USA), was inhabited by the Kayenta Anasazi from circa 1800 B.C. to circa A.D. 1300. These people were prehistoric precursors of the modern Pueblo cultures of the Colorado Plateau. A rich paleoenvironmental record, based on alluvial geomorphology, palynology, and dendroclimatology, permits the accurate quantitative reconstruction of annual fluctuations in potential agricultural production (kg maize/hectare). The archaeological record of Anasazi farming groups from A.D. 200 to 1300 provides information on a millennium of sociocultural stasis, variability, change, and adaptation. We report on a multi-agent computational model of this society that closely reproduces the main features of its actual history, including population ebb and flow, changing spatial settlement patterns, and eventual rapid decline. The agents in the model are monoagriculturalists, who decide both where to situate their fields and where to locate their settlements.

  12. Cultural ecology of prehistoric parasitism on the Colorado Plateau as evidenced by coprology.

    PubMed

    Reinhard, K J

    1988-11-01

    The study of coprolites (desiccated feces) is recognized as a viable method for analyzing parasitism of prehistoric peoples. Eight species of helminth parasites, including nematodes, cestodes, and acanthcephalans, have been recovered from archaeological sites on the Colorado Plateau. The comparative analysis of parasitological findings illustrates the effects of changing subsistence strategies and varying life-style on prehistoric human parasitism. This comparative study is based on the analysis of coprolites recovered from one Archaic hunter-gatherer site and two Anasazi agricultural villages. Hunter-gatherers are represented by coprolites from Dust Devil Cave in south-eastern Utah. Coprolites of prehistoric agriculturalists from Antelope House in Canyon de Chelly, Arizona, and from Salmon Ruin in northwestern New Mexico were studied. The results demonstrate that helminth parasitism increased with the advent of agriculture. Between the agricultural sites, differences in patterns of excreta disposal, foraging behavior, and local ecology resulted in pronounced variations in both percentage of coprolites containing parasite remains and the number of parasite species represented.

  13. Archaeogenomic evidence reveals prehistoric matrilineal dynasty

    PubMed Central

    Kennett, Douglas J.; Plog, Stephen; George, Richard J.; Culleton, Brendan J.; Watson, Adam S.; Skoglund, Pontus; Rohland, Nadin; Mallick, Swapan; Stewardson, Kristin; Kistler, Logan; LeBlanc, Steven A.; Whiteley, Peter M.; Reich, David; Perry, George H.

    2017-01-01

    For societies with writing systems, hereditary leadership is documented as one of the hallmarks of early political complexity and governance. In contrast, it is unknown whether hereditary succession played a role in the early formation of prehistoric complex societies that lacked writing. Here we use an archaeogenomic approach to identify an elite matriline that persisted between 800 and 1130 CE in Chaco Canyon, the centre of an expansive prehistoric complex society in the Southwestern United States. We show that nine individuals buried in an elite crypt at Pueblo Bonito, the largest structure in the canyon, have identical mitochondrial genomes. Analyses of nuclear genome data from six samples with the highest DNA preservation demonstrate mother–daughter and grandmother–grandson relationships, evidence for a multigenerational matrilineal descent group. Together, these results demonstrate the persistence of an elite matriline in Chaco for ∼330 years. PMID:28221340

  14. Remote sensing and the assessment of prehistoric productivity in cultivation practices of Rapa Nui, Chile

    NASA Astrophysics Data System (ADS)

    Kovalchik, Jacob

    While there is a tradition that the population of Rapa Nui was large during prehistory, there is remarkably little evidence used to support to these claims. This study represents an empirically-based estimate of pre-contact agricultural productivity to create a sound evaluation of Rapa Nui's prehistoric population. In this study, I map the spatial distributions of lithic mulching using satellite imagery, RPV aerial photography, in situ spectral reflectance analyses, and supervised and sub-pixel image classification methods. Using the results of these analyses, I estimate the total mapped lithic mulch area and combine this estimate with previously documented distributions of manavai. Together these analyses provide an estimate of the extent of these two important cultivation practices and an upper-limit magnitude of prehistoric food production. The spatial data, when evaluated in conjunction with appropriate agricultural cultivation statistic proxies, are then used to conservatively quantify the island's carrying capacity. In my final analysis, I argue that the prehistoric productivity was insufficient to support the large populations that have been suggested.

  15. Prehistoric land use in southern Loess Plateau reconstructed from archeological data by a new developed model

    NASA Astrophysics Data System (ADS)

    Yu, Y.; Wu, H.; Guo, Z.

    2014-12-01

    Estimation of land use during the Holocene is crucial to understand impacts of human activity on climate change in preindustrial period. Until now it is still a key issue to reconstruct amount and spatial distribution of prehistoric land use due to lack of data. Most reconstructions are simply extrapolations of population, cleared land amount per person and land suitability for agriculture. In this study, a new quantitative prehistoric land use model (PLUM) is developed based on semi-quantitative predictive models of archeological sites. The PLUM is driven by environmental and social parameters of archeological sites, which are objective evidences of prehistoric human activity, and produces realistic patterns of land use. After successful validations of the model with modern observed data, the PLUM was applied to reconstruct land use from 8 to 4 ka B.P. in Yiluo and Wei valleys, southern Loess Plateau. Both of them are the most important agriculture origin centers in northern China. Results reveal that about 9% of land areas in both valleys have been used by human activity from 8 to 4 ka B.P., expanding from gentle slopes along the river to hinterlands of the valleys. The land cover was affected by increasing agricultural land use during the middle Holocene. The extensive spreads of land use since 7 ka B.P. in both valleys were driven by the combined impacts of population increase and agriculture development, which was further favored by wet and warm climate conditions during middle Holocene; while the decreasing rates of land use expansions after 5 ka B.P. were mainly induced by improved agriculture technology. With the scaling up of PLUM to larger regional or global levels by a greater use of archeological data, the impact of human land use on global change can be studied more accurately.

  16. Prehistorical record of cultural eutrophication from Crawford Lake, Canada

    NASA Astrophysics Data System (ADS)

    Ekdahl, Erik J.; Teranes, Jane L.; Guilderson, Thomas P.; Turton, Charles L.; McAndrews, John H.; Wittkop, Chad A.; Stoermer, Eugene F.

    2004-09-01

    Cultural eutrophication—the process by which human activities increase nutrient input rates to aquatic ecosystems and thereby cause undesirable changes in surface-water quality—is generally thought to have begun with the start of the industrial era. The prehistoric dimension of human impacts on aquatic ecosystems remains relatively undescribed, particularly in North America. Here we present fossil plankton data (diatoms and rotifers), organic and inorganic carbon accumulations, and carbon isotope ratios from a 1000 yr sediment core record from Crawford Lake, Ontario, Canada. The data document increased nutrient input to Crawford Lake caused by Iroquoian horticultural activity from A.D. 1268 to 1486 and show how this increased nutrient input elevated lake productivity, caused bottom-water anoxia, and irreversibly altered diatom community structure within just a few years. Iroquoian settlement in the region declined in the fifteenth century, yet diatom communities and lake circulation never recovered to the predisturbance state. A second phase of cultural eutrophication starting in A.D. 1867, initiated by Canadian agricultural disturbance, increased lake productivity but had comparatively less impact on diatom assemblages and carbon-storage pathways than the initial Iroquoian disturbance. This study deepens our understanding of the impact of cultural eutrophication on lake systems, highlights the lasting influence of initial environmental perturbation, and contributes to the debate on the ecological impacts of density and agricultural practices of native North American inhabitants.

  17. A Prehistorical Record of Cultural Eutrophication from Crawford Lake, Canada

    SciTech Connect

    Ekdahl, E J; Teranes, J; Guilderson, T; Turton, C L; McAndrews, J H; Wittkop, C A; Stoermer, E F

    2004-08-05

    Cultural eutrophication--the process by which human activities increase nutrient input rates to aquatic ecosystems and thereby cause undesirable changes in surface-water quality--is generally thought to have begun with the start of the industrial era. The prehistoric dimension of human impacts on aquatic ecosystems remains relatively undescribed, particularly in North America. Here we present fossil plankton data (diatoms and rotifers), organic and inorganic carbon accumulations, and carbon isotope ratios from a 1000-yr sediment core record from Crawford Lake, Ontario, Canada. The data documents increased nutrient input to Crawford Lake caused by Iroquoian horticultural activity from A.D. 1268 to 1486 and shows how this increased nutrient input elevated lake productivity, caused bottom-water anoxia, and irreversibly altered diatom community structure within just a few years. Iroquoian settlement in the region declined in the fifteenth century, yet diatom communities and lake circulation never recovered to the predisturbance state. A second phase of cultural eutrophication starting in A.D. 1867, initiated by Canadian agricultural disturbance, increased lake productivity but had comparatively less of an impact on diatom assemblages and carbon-storage pathways than the initial Iroquoian disturbance. This study deepens our understanding of the impact of cultural eutrophication on lake systems, highlights the lasting influence of initial environmental perturbation, and contributes to the debate on the ecological impacts of density and agricultural practices of native North American inhabitants.

  18. Rapid prehistoric extinction of iguanas and birds in Polynesia.

    PubMed

    Steadman, David W; Pregill, Gregory K; Burley, David V

    2002-03-19

    The Tongoleleka archaeological site on Lifuka Island, Kingdom of Tonga, is a rich accumulation of pottery, marine mollusks, and nonhuman bones that represents first human contact on a small island in Remote Oceania approximately 2,850 years ago. The lower strata contain decorated Lapita-style pottery and bones of an extinct iguana (Brachylophus undescribed sp.) and numerous species of extinct birds. The upper strata instead feature Polynesian Plainware pottery and bones of extant species of vertebrates. A stratigraphic series of 20 accelerator-mass spectrometer radiocarbon dates on individual bones of the iguana, an extinct megapode (Megapodius alimentum), and the non-native chicken (Gallus gallus) suggests that anthropogenic loss of the first two species and introduction of the latter occurred on Lifuka within a time interval too short (a century or less) to be resolved by radiometric dating. The geologically instantaneous prehistoric collapse of Lifuka's vertebrate community contrasts with the much longer periods of faunal depletion on some other islands, thus showing that the elapse time between human arrival and major extinction events was highly variable on oceanic islands as well as on continents.

  19. Rapid prehistoric extinction of iguanas and birds in Polynesia

    PubMed Central

    Steadman, David W.; Pregill, Gregory K.; Burley, David V.

    2002-01-01

    The Tongoleleka archaeological site on Lifuka Island, Kingdom of Tonga, is a rich accumulation of pottery, marine mollusks, and nonhuman bones that represents first human contact on a small island in Remote Oceania ≈2,850 years ago. The lower strata contain decorated Lapita-style pottery and bones of an extinct iguana (Brachylophus undescribed sp.) and numerous species of extinct birds. The upper strata instead feature Polynesian Plainware pottery and bones of extant species of vertebrates. A stratigraphic series of 20 accelerator-mass spectrometer radiocarbon dates on individual bones of the iguana, an extinct megapode (Megapodius alimentum), and the non-native chicken (Gallus gallus) suggests that anthropogenic loss of the first two species and introduction of the latter occurred on Lifuka within a time interval too short (a century or less) to be resolved by radiometric dating. The geologically instantaneous prehistoric collapse of Lifuka's vertebrate community contrasts with the much longer periods of faunal depletion on some other islands, thus showing that the elapse time between human arrival and major extinction events was highly variable on oceanic islands as well as on continents. PMID:11904427

  20. Potential depletion of surface water in the Colorado River and agricultural drains by groundwater pumping in the Parker-Palo Verde-Cibola area, Arizona and California

    USGS Publications Warehouse

    Leake, Stanley A.; Owen-Joyce, Sandra J.; Heilman, Julian A.

    2013-01-01

    Water use along the lower Colorado River is allocated as “consumptive use,” which is defined to be the amount of water diverted from the river minus the amount that returns to the river. Diversions of water from the river include surface water in canals and water removed from the river by pumping wells in the aquifer connected to the river. A complication in accounting for water pumped by wells occurs if the pumping depletes water in drains and reduces measured return flow in those drains. In that case, consumptive use of water pumped by the wells is accounted for in the reduction of measured return flow. A method is needed to understand where groundwater pumping will deplete water in the river and where it will deplete water in drains. To provide a basis for future accounting for pumped groundwater in the Parker-Palo Verde-Cibola area, a superposition model was constructed. The model consists of three layers of finite-difference cells that cover most of the aquifer in the study area. The model was run repeatedly with each run having a pumping well in a different model cell. The source of pumped water that is depletion of the river, expressed as a fraction of the pumping rate, was computed for all active cells in model layer 1, and maps were constructed to understand where groundwater pumping depletes the river and where it depletes drains. The model results indicate that if one or more drains exist between a pumping well location and the river, nearly all of the depletion will be from drains, and little or no depletion will come from the Colorado River. Results also show that if a well pumps on a side of the river with no drains in the immediate area, depletion will come from the Colorado River. Finally, if a well pumps between the river and drains that parallel the river, a fraction of the pumping will come from the river and the rest will come from the drains. Model results presented in this report may be considered in development or refinement of strategies

  1. Palaeolithic paintings. Evolution of prehistoric cave art.

    PubMed

    Valladas, H; Clottes, J; Geneste, J M; Garcia, M A; Arnold, M; Cachier, H; Tisnérat-Laborde, N

    2001-10-04

    Sophisticated examples of European palaeolithic parietal art can be seen in the caves of Altamira, Lascaux and Niaux near the Pyrenees, which date to the Magdalenian period (12,000-17,000 years ago), but paintings of comparable skill and complexity were created much earlier, some possibly more than 30,000 years ago. We have derived new radiocarbon dates for the drawings that decorate the Chauvet cave in Vallon-Pont-d'Arc, Ardèche, France, which confirm that even 30,000 years ago Aurignacian artists, already known as accomplished carvers, could create masterpieces comparable to the best Magdalenian art. Prehistorians, who have traditionally interpreted the evolution of prehistoric art as a steady progression from simple to more complex representations, may have to reconsider existing theories of the origins of art.

  2. Prehistoric Versus Historic Floodplain Sedimentation Rates in the Upper Little Tennessee River Valley, Blue Ridge Mountains, North Carolina, USA

    NASA Astrophysics Data System (ADS)

    Leigh, D. S.

    2008-12-01

    Late prehistoric and historic floodplain sedimentation rates were examined along the Upper Little Tennessee River within a 363 km2 catchment of the Southern Blue Ridge Mountains in western North Carolina. Sedimentation rates were derived from stratigraphy, sedimentology, radiocarbon and cesium-137 dates at three mainstem floodplain sample sites using cores and outcrops. Particle size was measured in continuous down-column overbank sediment samples (1-3 cm increments) to document individual floods as time markers. Results indicate that late prehistoric sedimentation rates were less than 1 mm/yr, whereas historical sedimentation rates are about an order of magnitude higher (5 to 17 mm/yr). The historical floodplain has accreted up to two meters higher than prehistoric levels, while the channel bed remains approximately at prehistoric levels. The most rapid historical sedimentation rates of 13-17 mm/yr occurred between 1963 and 2004, corresponding to a time period of second home construction, road construction, and other erosive land uses related to population and infrastructure growth; whereas pre-1963 historical sedimentation rates correspond to former timber harvest and agricultural activities. The most recent phase from1963 to present also corresponds to a time of relatively rapid lateral migration, incipient floodplain formation, and natural levee progradation on historically terraced cutbanks. Ongoing research relates channel morphogenesis, bank erosion, and remobilization of historical sediment to the overall sediment budget.

  3. Farming in Prehistoric Europe: modelling the impact of the first agriculturists on the landscape

    NASA Astrophysics Data System (ADS)

    van Beek, Rens; Feiken, Rik

    2013-04-01

    The meso-scale landscape dynamics model, CALEROS, has been developed to simulate the interactions between climate, soil production and erosion, vegetation and land use on geomorphological to human time scales in Mediterranean environments. In this study we re-evaluate the scenarios of Gregg (1988) to explore the options open to the first, Neolithic farmers in such an environment. Starting from a static model, we evaluate optimal farming strategies across a Mediterranean landscape gradient in and compare this to the outcome of Gregg's study for temperate Europe in order to reveal inter-regional and local differences and the sensitivity to the underlying assumptions. Subsequently, the impact of agriculture on the landscape is implemented and dynamically evaluated in terms of primary production and sediment yield. Thus, the stability of the first agricultural ecosystems is explored and the ultimate carrying capacity of the Neolithic landscape determined. Gregg, S.A. (1988): Foragers and Farmers: Population Interaction and Agricultural Expansion in Prehistoric Europe. In: Butzer & Freeman (Eds.), Prehistoric Archeology and Ecology Series. The University of Chicago Press, Chicago, pp. 275.

  4. Palaeotsunamis and their significance for prehistoric coastal communities

    NASA Astrophysics Data System (ADS)

    Goff, J. R.

    2011-12-01

    The damage caused by large tsunamis to human populations at the coast has been all too evident over the past few years. However, while we have seen the immediate after-effects of such events, we are less familiar with the longer term changes associated with them. Using prehistoric New Zealand as a case study, the talk first addresses the wider geological context associated with a tsunami - what caused it and what were the consequences for the physical environment? Prehistoric Maori lived predominantly in coastal settlements, particularly during their early settlement period. They had far ranging canoe trade routes and made widespread use of intertidal and coastal resources. As such it is possible to determine much of the ecological and societal ramifications of a 15th century tsunami inundation. The 15th century tsunami is recorded in numerous purakau or oral recordings. These form part of Maori Traditional Environmental Knowledge (TEK), but the event can also be identified through archaeological, geological and palaeo-ecological indicators. One of several purakau from the 15th century refers to the "Coming of the Sand". This centres on a place called Potiki-taua, where Potiki and his group settled. Mango-huruhuru, the old priest, built a large house on low land near the sea while Potiki-roa and his wife put theirs on higher ground further inland. Mango-huruhuru's house had a rocky beach in front of it that was unsuitable for landing canoes and so he decided to use his powers to bring sand from Hawaiki. After sunset he sat on his roof and recited a karakia (prayer/chant). On conclusion a dark cloud with its burden of sand reached the shore. The women called out "A! The sea rises; the waves and the sand will overwhelm us". The people fell where they stood and were buried in the sand along with the house and cultivations and all the surrounding country, and with them, the old priest and his youngest daughter (memorialised and turned into a rock which stands there

  5. A new population curve for prehistoric Australia.

    PubMed

    Williams, Alan N

    2013-06-22

    This paper presents a new reconstruction of prehistoric population of Australia for the last 50 ka, using the most comprehensive radiocarbon database currently available for the continent. The application of new techniques to manipulate radiocarbon data (including correction for taphonomic bias), gives greater reliability to the reconstructed population curve. This shows low populations through the Late Pleistocene, before a slow stepwise increase in population beginning during the Holocene transition (approx. 12 ka) and continuing in pulses (approx. 8.3-6.6, 4.4-3.7 and 1.6-0.4 ka) through the Holocene. These data give no support for an early saturation of the continent, although the estimated population following initial landfall was probably greater than previously allowed (comparable with the Early Holocene). The greatest increase in population occurred in the Late Holocene, but in contrast to existing intensification models, changes in demography and diversification of economic activities began much earlier. Some demographic changes appear to be in response to major climatic events, most notably during the last glacial maximum, where the curve suggests that population fell by about 60 per cent between 21 and 18 ka. An application of statistical demographic methods to Australian ethnographic and genetic data suggests that a founding group of 1000-2000 at 50 ka would result in a population high of approximately 1.2 million at approximately 0.5 ka. Data suggests an 8 per cent decline to approximately 770 000-1.1 million at the time of European contact, giving a figure consistent with ethnographic estimates and with historical observations of the impact of smallpox, and other diseases introduced by Macassans and Europeans during and after AD 1788.

  6. A new population curve for prehistoric Australia

    PubMed Central

    Williams, Alan N.

    2013-01-01

    This paper presents a new reconstruction of prehistoric population of Australia for the last 50 ka, using the most comprehensive radiocarbon database currently available for the continent. The application of new techniques to manipulate radiocarbon data (including correction for taphonomic bias), gives greater reliability to the reconstructed population curve. This shows low populations through the Late Pleistocene, before a slow stepwise increase in population beginning during the Holocene transition (approx. 12 ka) and continuing in pulses (approx. 8.3–6.6, 4.4–3.7 and 1.6–0.4 ka) through the Holocene. These data give no support for an early saturation of the continent, although the estimated population following initial landfall was probably greater than previously allowed (comparable with the Early Holocene). The greatest increase in population occurred in the Late Holocene, but in contrast to existing intensification models, changes in demography and diversification of economic activities began much earlier. Some demographic changes appear to be in response to major climatic events, most notably during the last glacial maximum, where the curve suggests that population fell by about 60 per cent between 21 and 18 ka. An application of statistical demographic methods to Australian ethnographic and genetic data suggests that a founding group of 1000–2000 at 50 ka would result in a population high of approximately 1.2 million at approximately 0.5 ka. Data suggests an 8 per cent decline to approximately 770 000–1.1 million at the time of European contact, giving a figure consistent with ethnographic estimates and with historical observations of the impact of smallpox, and other diseases introduced by Macassans and Europeans during and after AD 1788. PMID:23615287

  7. A GIS approach for predicting prehistoric site locations.

    SciTech Connect

    Kuiper, J. A.; Wescott, K. L.

    1999-08-04

    Use of geographic information system (GIS)-based predictive mapping to locate areas of high potential for prehistoric archaeological sites is becoming increasingly popular among archaeologists. Knowledge of the environmental variables influencing activities of original inhabitants is used to produce GIS layers representing the spatial distribution of those variables. The GIS layers are then analyzed to identify locations where combinations of environmental variables match patterns observed at known prehistoric sites. Presented are the results of a study to locate high-potential areas for prehistoric sites in a largely unsurveyed area of 39,000 acres in the Upper Chesapeake Bay region, including details of the analysis process. The project used environmental data from over 500 known sites in other parts of the region and the results corresponded well with known sites in the study area.

  8. Prehistoric Journey: Denver Museum of Natural History Educators' Sourcebook.

    ERIC Educational Resources Information Center

    Smith, Rebecca L.; Leigh, Vicki; Crew, Diana Lee

    This sourcebook prepares students for a visit to the "Prehistoric Journey" exhibit at the Denver Museum of Natural History. The exhibit opened October 23, 1995, and offered a dramatic exploration of 3.5 billion years of life on Earth. Dioramas and "enviroramas" depict seven critical points in life's history. In addition to the chronological…

  9. Affixation and Inflection in Pre-Historic Indo-European.

    ERIC Educational Resources Information Center

    Scholes, Robert J.

    A discussion of pre-historic (i.e., preliterate) language looks at the processes of affixation and inflection in the context of two conflicting theories on the complexity of those languages. The traditional view holds that the grammar used by early Indo-Europeans was at least as complex and abstract as that of any modern educated and literate…

  10. The role of changing childhood diets in the prehistoric evolution of food production: An isotopic assessment.

    PubMed

    Schurr, Mark R; Powell, Mary Lucas

    2005-03-01

    Earlier weaning has often been suggested as a cause for population growth after the evolution of food production. However, evidence for weaning-time reduction is largely circumstantial. Collagen stable nitrogen- and carbon-isotope ratios from juvenile and adult burials from four sites in eastern North America were measured to estimate weaning onsets and durations before and after the appearance of intensive food production. Two preagricultural Late Archaic sites (Indian Knoll and Carlston Annis) are compared with two highly agricultural Middle Mississippian sites (Angel and Tinsley Hill). Isotopic data and paleodemographic measures of birth rates provide no evidence for changes in weaning behavior or fertility with the development of food production in the prehistoric Lower Ohio Valley. Birth rates and weaning behavior appear to have been roughly the same at all four sites. These results indicate that models attributing population growth after the appearance of food production to earlier weaning are not universally applicable.

  11. Mössbauer studies of prehistoric Cherokee pottery sherds

    NASA Astrophysics Data System (ADS)

    Whatley, K. M.; McKenzie, K. P.

    1994-12-01

    Mössbauer spectroscopy is a very useful tool in the examination and characterization of ancient pottery sherds. In this study, Mössbauer spectra for sherds and clay from the Warren Wilson Site, a prehistoric Native American (Cherokee) settlement in western North Carolina, were measured. Data from one sherd and samples from two clay beds indicate that the sherd was not made from local clays and was originally fired to 350 ‡C.

  12. Psychoacoustic influences of the echoing environments of prehistoric art

    NASA Astrophysics Data System (ADS)

    Waller, Steven J.

    2002-11-01

    Cave paintings and ancient petroglyphs around the world are typically found in echo rich locations such as caves, canyons, and rocky cliff faces. Analysis of field data shows that echo decibel levels at a large number of prehistoric art sites are higher than those at nondecorated locations. The selection of these echoing environments by the artists appears not to be a mere coincidence. This paper considers the perception of an echoed sound as a psychoacoustic event that would have been inexplicable to ancient humans. A variety of ancient legends from cultures on several continents attribute the phenomenon of echoes to supernatural beings. These legends, together with the quantitative data, strongly implicate echoing as relevant to the artists of the past. The notion that the echoes were caused by spirits within the rock would explain not only the unusual locations of prehistoric art, but also the perplexing subject matter. For example, the common theme of hoofed animal imagery could have been inspired by echoes of percussion noises perceived as hoof beats. Further systematic acoustical studies of prehistoric art sites is warranted. Conservation of the natural acoustic properties of rock art environments--a previously unrecognized need--is urged.

  13. Interisland and interarchipelago transfer of stone tools in prehistoric Polynesia.

    PubMed

    Weisler, M I; Kirch, P V

    1996-02-20

    Tracing interisland and interarchipelago movements of people and artifacts in prehistoric Polynesia has posed a challenge to archaeologists due to the lack of pottery and obsidian, two materials most readily used in studies of prehistoric trade or exchange. Here we report the application of nondestructive energy-dispersive x-ray fluorescence (EDXRF) analysis to the sourcing of Polynesian artifacts made from basalt, one of the most ubiquitous materials in Polynesian archaeological sites. We have compared excavated and surface-collected basalt adzes and adze flakes from two sites in Samoa (site AS-13-1) and the Cook Islands (site MAN-44), with source basalts from known prehistoric quarries in these archipelagoes. In both cases, we are able to demonstrate the importing of basalt adzes from Tutuila Island, a distance of 100 km to Ofu Island, and of 1600 km to Mangaia Island. These findings are of considerable significance for Polynesian prehistory, as they demonstrate the movement of objects not only between islands in the same group (where communities were culturally and linguistically related) but also between distant island groups. Further applications of EDXRF analysis should greatly aid archaeologists in their efforts to reconstruct ancient trade and exchange networks, not only in Polynesia but also in other regions where basalt was a major material for artifact production.

  14. Prehistoric tuberculosis in america: adding comments to a literature review.

    PubMed

    Gómez i Prat, Jordi; de Souza, Sheila M F Mendonça

    2003-01-01

    Tuberculosis is a prehistoric American human disease. This paper reviews the literature and discusses hypotheses for origins and epidemiological patterns of prehistoric tuberculosis. From the last decades, 24 papers about prehistoric tuberculosis were published and 133 cases were reviewed. In South America most are isolated case studies, contrary to North America where more skeletal series were analyzed. Disease was usually located at the deserts of Chile and Peru, Central Plains in USA, and Lake Ontario in Canada. Skeletal remains represent most of the cases, but 16 mummies have also been described. Thirty individuals had lung disease, 19 of them diagnosed by the ribs. More then 100 individuals had osseous tuberculosis and 26 also had it in other organs. As today, transmission of the infection and establishment of the disease were favored by cultural and life-style changes such as sedentarization, crowding, undernutrition, use of dark and insulated houses, and by the frequency of interpersonal contacts. The papers confirm that despite previous perceptions, tuberculosis seems to have occurred in America for millennia. It only had epidemiological expression when special conditions favored its expansion. Occurring as epidemic bursts or low endemic disease, it had differential impact on groups or social segments in America for at least two millennia.

  15. Interisland and interarchipelago transfer of stone tools in prehistoric Polynesia.

    PubMed Central

    Weisler, M I; Kirch, P V

    1996-01-01

    Tracing interisland and interarchipelago movements of people and artifacts in prehistoric Polynesia has posed a challenge to archaeologists due to the lack of pottery and obsidian, two materials most readily used in studies of prehistoric trade or exchange. Here we report the application of nondestructive energy-dispersive x-ray fluorescence (EDXRF) analysis to the sourcing of Polynesian artifacts made from basalt, one of the most ubiquitous materials in Polynesian archaeological sites. We have compared excavated and surface-collected basalt adzes and adze flakes from two sites in Samoa (site AS-13-1) and the Cook Islands (site MAN-44), with source basalts from known prehistoric quarries in these archipelagoes. In both cases, we are able to demonstrate the importing of basalt adzes from Tutuila Island, a distance of 100 km to Ofu Island, and of 1600 km to Mangaia Island. These findings are of considerable significance for Polynesian prehistory, as they demonstrate the movement of objects not only between islands in the same group (where communities were culturally and linguistically related) but also between distant island groups. Further applications of EDXRF analysis should greatly aid archaeologists in their efforts to reconstruct ancient trade and exchange networks, not only in Polynesia but also in other regions where basalt was a major material for artifact production. PMID:8643640

  16. Settlement-Size Scaling among Prehistoric Hunter-Gatherer Settlement Systems in the New World

    PubMed Central

    Haas, W. Randall; Klink, Cynthia J.; Maggard, Greg J.; Aldenderfer, Mark S.

    2015-01-01

    Settlement size predicts extreme variation in the rates and magnitudes of many social and ecological processes in human societies. Yet, the factors that drive human settlement-size variation remain poorly understood. Size variation among economically integrated settlements tends to be heavy tailed such that the smallest settlements are extremely common and the largest settlements extremely large and rare. The upper tail of this size distribution is often formalized mathematically as a power-law function. Explanations for this scaling structure in human settlement systems tend to emphasize complex socioeconomic processes including agriculture, manufacturing, and warfare—behaviors that tend to differentially nucleate and disperse populations hierarchically among settlements. But, the degree to which heavy-tailed settlement-size variation requires such complex behaviors remains unclear. By examining the settlement patterns of eight prehistoric New World hunter-gatherer settlement systems spanning three distinct environmental contexts, this analysis explores the degree to which heavy-tailed settlement-size scaling depends on the aforementioned socioeconomic complexities. Surprisingly, the analysis finds that power-law models offer plausible and parsimonious statistical descriptions of prehistoric hunter-gatherer settlement-size variation. This finding reveals that incipient forms of hierarchical settlement structure may have preceded socioeconomic complexity in human societies and points to a need for additional research to explicate how mobile foragers came to exhibit settlement patterns that are more commonly associated with hierarchical organization. We propose that hunter-gatherer mobility with preferential attachment to previously occupied locations may account for the observed structure in site-size variation. PMID:26536241

  17. Settlement-Size Scaling among Prehistoric Hunter-Gatherer Settlement Systems in the New World.

    PubMed

    Haas, W Randall; Klink, Cynthia J; Maggard, Greg J; Aldenderfer, Mark S

    2015-01-01

    Settlement size predicts extreme variation in the rates and magnitudes of many social and ecological processes in human societies. Yet, the factors that drive human settlement-size variation remain poorly understood. Size variation among economically integrated settlements tends to be heavy tailed such that the smallest settlements are extremely common and the largest settlements extremely large and rare. The upper tail of this size distribution is often formalized mathematically as a power-law function. Explanations for this scaling structure in human settlement systems tend to emphasize complex socioeconomic processes including agriculture, manufacturing, and warfare-behaviors that tend to differentially nucleate and disperse populations hierarchically among settlements. But, the degree to which heavy-tailed settlement-size variation requires such complex behaviors remains unclear. By examining the settlement patterns of eight prehistoric New World hunter-gatherer settlement systems spanning three distinct environmental contexts, this analysis explores the degree to which heavy-tailed settlement-size scaling depends on the aforementioned socioeconomic complexities. Surprisingly, the analysis finds that power-law models offer plausible and parsimonious statistical descriptions of prehistoric hunter-gatherer settlement-size variation. This finding reveals that incipient forms of hierarchical settlement structure may have preceded socioeconomic complexity in human societies and points to a need for additional research to explicate how mobile foragers came to exhibit settlement patterns that are more commonly associated with hierarchical organization. We propose that hunter-gatherer mobility with preferential attachment to previously occupied locations may account for the observed structure in site-size variation.

  18. Prehistoric rock avalanches in the Olympic Mountains, Washington

    USGS Publications Warehouse

    Schuster, R.L.; Logan, R.L.; Pringle, P.T.

    1992-01-01

    Rock avalanches blocked streams in the Olympic Mountains southwest of Puget Sound during the past few thousand years. Limiting radiocarbon ages indicated that three or four of six avalanches occurred from 1000 to 1300 years ago or shortly thereafter. Most of the dates were from the outer preserved rings of trees drowned behind avalanche dams. These three or four avalanches may be coeval not only with one another but also with abrupt tectonic deformation in western Washington. No rock avalanches in the Olympic Mountains are known to have resulted from storms or earthquakes during the past century. The avalanches strengthen the case that a large prehistoric earthquake occurred in the Puget Sound region.

  19. Craniometric variation and population history of the prehistoric Tewa.

    PubMed

    Schillaci, Michael A; Stojanowski, Christopher M

    2005-04-01

    Although the population history and social organization of the prehistoric Pueblo Indians of the American Southwest have received attention in the archaeological literature, little research on this topic has been conducted by biological anthropologists. Here, we examine postmarital residence at two ancestral Tewa Indian pueblos located in north-central New Mexico using determinant ratio analysis. In addition, we examine genetic relationships among pueblos, as well as levels of within-pueblo heterogeneity due to gene flow from extraregional sources, or regional aggregation. Results from determinant ratio analysis indicate greater within-pueblo male variation, consistent with matrilocal residence for at least one Tewa pueblo. Less than expected heterogeneity at two pueblos suggests that endogamy might have been practiced among some prehistoric Tewa pueblos. Gene flow from extraregional sources is indicated for two different pueblos by greater than expected within-group heterogeneity. Distance matrix correlation analyses indicate little if any relationship between phenotypic and geographic distances, suggesting that geography was not the primary basis of gene flow or mate exchange. The weak relationship between phenotypic and geographic distances may be the combined effects of endogamy at some pueblos, nonrandom extraregional gene flow or migration at other pueblos, and limited nonproximity-dependent regional gene flow or migration among pueblos, possibly structured on ritual exchange networks based on medicine society affiliation.

  20. Coca chewing in prehistoric coastal Peru: dental evidence.

    PubMed

    Indriati, E; Buikstra, J E

    2001-03-01

    In this study, we describe the dental health of four prehistoric human populations from the southern coast of Peru, an area in which independent archaeological evidence suggests that the practice of coca-leaf chewing was relatively common. A repeated pattern of cervical-root caries accompanying root exposure was found on the buccal surfaces of the posterior dentition, coinciding with the typical placement of coca quids during mastication. To further examine the association between caries patterning and coca chewing, caries site characteristics of molar teeth were utilized as indicators for estimating the likelihood of coca chewing for adults within each of the study samples. Likelihood estimates were then compared with results of a test for coca use derived from hair samples from the same individuals. The hair and dental studies exhibited an 85.7% agreement. Thus, we have demonstrated the validity of a hard-tissue technique for identifying the presence of habitual coca-leaf chewing in ancient human remains, which is useful in archaeological contexts where hair is not preserved. These data can be used to explore the distribution of coca chewing in prehistoric times. Simultaneously, we document the dental health associated with this traditional Andean cultural practice. Copyright 2001 Wiley-Liss, Inc.

  1. Freud's prehistoric matrix--owing 'nature' a death.

    PubMed

    Raphael-Leff, Joan

    2007-12-01

    This paper is informed by contemporary literature in two fields--neonatal research, on the one hand, and the burgeoning interdisciplinary interest in Moses and monotheism, on the other. The author postulates that a cluster of traumatic events during the first two years of Freud's life compelled him to repeat what could not be remembered. Embedded in charged implicit schema, these affects remained unprocessed in Freud, who alone of all psychoanalysts did not have an analysis, manifesting in an uncanny dread/allure of the 'prehistoric' as a dark and dangerous era relating to the archaic feminine/maternal matrix and fratricidal murderousness. Furthermore, she cites evidence to suggest that for Freud this unconsciously excluded subtext of the preoedipal era became associated with ancient Egyptian and Minoan-Mycenaean cultures, a passionate fascination actualized in his collection of antiquities yet incongruously absent in his theoretical work, with three exceptions--Egyptian allusions in Leonardo's unconscious attachment to his archaic mother; the 'Minoan-Mycenaean' analogy on discovering the pre-oedipal mother shortly after the death of Freud's own mother; and Egypt as cradle of humanity in his uncharacteristically rambling, troubled text of Moses and monotheism. The author sees Freud's conceptual avoidance yet compulsive reworking of the prehistoric matrix as a symptomatic attempt to expose early unformulated representations that 'return to exert a powerful effect'.

  2. Archeological Applications of XAFS: Prehistorical Paintings And Medieval Glasses

    SciTech Connect

    Farges, F.; Chalmin, E.; Vignaud, C.; Pallot-Frossard, I.; Susini, J.; Bargar, J.; Brown, G.E., Jr.; Menu, M.; /SLAC, SSRL

    2006-10-27

    High-resolution manganese and iron K-edges XANES spectra were collected on several samples of archeological interest: prehistorical paintings and medieval glasses. XANES spectra were collected at the ID21 facility (ESRF, Grenoble, France) using a micro-beam device and at the 11-2 beamline (SSRL, Stanford, USA) using a submillimetric beam. The medieval glasses studied are from gothic glass windows from Normandy (XIVth century). The aim of this study is to help understand the chemical durability of these materials, exposed to weathering since the XIVth century. They are used as analogues of weathered glasses used to dump metallic wastes. These glasses show surficial enrichment in manganese, due to its oxidation from II (glass) to III/IV (surface), which precipitates as amorphous oxy-hydroxides. Similarly, iron is oxidized on the surface and forms ferrihydrite-type aggregates. The prehistorical paintings are from Lascaux and Ekain (Basque country). We choose in that study the black ones, rich in manganese to search for potential evidences of some 'savoir-faire' that the Paleolithic men could have used to realize their paint in rock art, as shown earlier for Fe-bearing pigments. A large number of highly valuable samples, micrometric scaled, were extracted from these frescoes and show large variation in the mineralogical nature of the black pigments used, from an amorphous psilomelane-type to a well-crystallized pyrolusite. Correlation with the crystals morphology helps understanding the know-how of these early artists.

  3. Variable effects of cinder-cone eruptions on prehistoric agrarian human populations in the American southwest

    NASA Astrophysics Data System (ADS)

    Ort, Michael H.; Elson, Mark D.; Anderson, Kirk C.; Duffield, Wendell A.; Samples, Terry L.

    2008-10-01

    Two ˜ 900 BP cinder-cone eruptions in the American Southwest affected prehistoric human populations in different ways, mostly because of differences in the eruption styles and area affected. Primary pre-eruption cultural factors that may have led to successful adaptation to the eruptions include decision-making at the family or household level, low investment in site structures, dispersion of agricultural sites in varied environments, and settlement spread over a large area so that those who were less affected could shelter and feed evacuees. Sunset Crater, near Flagstaff, Arizona, produced about 8 km 2 lava flow fields and a ˜ 2300-km 2 tephra blanket in an area that had been settled by prehistoric groups for at least 1000 years. Local subsistence relied on agriculture, primarily maize, and > 30 cm tephra cover rendered 265 km 2 of prime land unfarmable. This area was apparently abandoned for at least several generations. A > 500-km 2 area was probably marked by collapsed roofs and other structural damage from the fallout. If the eruption occurred during the agricultural season, the fallout would also have significantly damaged crops. The eruption did have some benefits to local groups because lower elevation land, which had previously been too dry to farm, became agriculturally productive due to 3-8 cm of tephra 'mulch' and some temporary soil nutrient improvements. This previously uninhabited land became the site of significant year-round settlement and farming, eventually containing some of the largest pueblo structures ever built in the region. New agricultural techniques were developed to manage the fallout mulch. The eruption also affected ceramic production and trading patterns, and volcano-related ritual behavior - the production of maize-impressed lava-spatter agglutinate - was initiated. Little Springs Volcano, about 200 km northwest of Sunset Crater, is a small spatter rampart around a series of vents that produced about 5 km 2 of lava flow fields

  4. Prehistoric Rock Structures of the Idaho National Laboratory

    SciTech Connect

    Brenda R Pace

    2007-04-01

    Over the past 13,500 years, human populations have lived in and productively utilized the natural resources offered by the cold desert environment of the northeastern Snake River Plain in eastern Idaho. Within an overall framework of hunting and gathering, groups relied on an intimate familiarity with the natural world and developed a variety of technologies to extract the resources that they needed to survive. Useful items were abundant and found everywhere on the landscape. Even the basaltic terrain and the rocks, themselves, were put to productive use. This paper presents a preliminary classification scheme for rock structures built on the Idaho National Laboratory landscape by prehistoric aboriginal populations, including discussions of the overall architecture of the structures, associated artifact assemblages, and topographic placement. Adopting an ecological perspective, the paper concludes with a discussion of the possible functions of these unique resources for the desert populations that once called the INL home.

  5. Problems in archaeomagnetic reference curves elaboration in the prehistoric past.

    NASA Astrophysics Data System (ADS)

    Avramova, M.; Kovacheva, M.; Boyadziev, Y.

    2012-04-01

    Most important task of archaeomagnetic studies is the construction of the geomagnetic field secular variations in the past for a given territory. The obtained reference curves would be precise only when a large number of well-dated archaeological sites from different time periods are included as input data. Sofia Palaeomagnetic laboratory is the first one in the Balkans to accumulate a large number of data spanning the time interval of 3000 BP to 8000 BP. Many archaeological sites in Bulgaria are multilevel settlements with clear stratigraphy. Commonly the prehistoric sites are dated according to the relative chronology, the type of archaeological artifacts found and 14C dates, the latter being not always available. The biggest difficulty is that usually the radiocarbon dates are not well constrained, often contradictory to the vertical stratigraphy. The transformation of conventional 14C dates to absolute dates BC depends a lot on which part of dendrochronological calibration curve are they related. Besides, multiple dating intervals are often obtained and the calibrated intervals are usually very large (from 100 to 300 and more years). However, when archaeological discoveries of multilevel prehistoric sites are combined with archaeomagnetic investigations the corresponding archaeomagnetic profiles can be obtained. Currently we have archaeomagnetic data for fifteen prehistoric multilevel sites - two of them are Neolithic, nine - Eneolithic and four are from the Bronze Age. The next step is to juxtapose these stratigraphic profiles with the absolute scale of time having in mind that not all sites and layers have 14C dates. Thanks to abundance of 14C dates for most of Bulgarian prehistoric sites, multilayer sites connected with the absolute chronology exist and can be used as reference profiles. The time frames of each horizon for such reference site are based on series of 14C dates (not single measurements), the analysis of the thickness of layers, type of material

  6. A substantial prehistoric European ancestry amongst Ashkenazi maternal lineages.

    PubMed

    Costa, Marta D; Pereira, Joana B; Pala, Maria; Fernandes, Verónica; Olivieri, Anna; Achilli, Alessandro; Perego, Ugo A; Rychkov, Sergei; Naumova, Oksana; Hatina, Jiři; Woodward, Scott R; Eng, Ken Khong; Macaulay, Vincent; Carr, Martin; Soares, Pedro; Pereira, Luísa; Richards, Martin B

    2013-01-01

    The origins of Ashkenazi Jews remain highly controversial. Like Judaism, mitochondrial DNA is passed along the maternal line. Its variation in the Ashkenazim is highly distinctive, with four major and numerous minor founders. However, due to their rarity in the general population, these founders have been difficult to trace to a source. Here we show that all four major founders, ~40% of Ashkenazi mtDNA variation, have ancestry in prehistoric Europe, rather than the Near East or Caucasus. Furthermore, most of the remaining minor founders share a similar deep European ancestry. Thus the great majority of Ashkenazi maternal lineages were not brought from the Levant, as commonly supposed, nor recruited in the Caucasus, as sometimes suggested, but assimilated within Europe. These results point to a significant role for the conversion of women in the formation of Ashkenazi communities, and provide the foundation for a detailed reconstruction of Ashkenazi genealogical history.

  7. A substantial prehistoric European ancestry amongst Ashkenazi maternal lineages

    PubMed Central

    Costa, Marta D.; Pereira, Joana B.; Pala, Maria; Fernandes, Verónica; Olivieri, Anna; Achilli, Alessandro; Perego, Ugo A.; Rychkov, Sergei; Naumova, Oksana; Hatina, Jiři; Woodward, Scott R.; Eng, Ken Khong; Macaulay, Vincent; Carr, Martin; Soares, Pedro; Pereira, Luísa; Richards, Martin B.

    2013-01-01

    The origins of Ashkenazi Jews remain highly controversial. Like Judaism, mitochondrial DNA is passed along the maternal line. Its variation in the Ashkenazim is highly distinctive, with four major and numerous minor founders. However, due to their rarity in the general population, these founders have been difficult to trace to a source. Here we show that all four major founders, ~40% of Ashkenazi mtDNA variation, have ancestry in prehistoric Europe, rather than the Near East or Caucasus. Furthermore, most of the remaining minor founders share a similar deep European ancestry. Thus the great majority of Ashkenazi maternal lineages were not brought from the Levant, as commonly supposed, nor recruited in the Caucasus, as sometimes suggested, but assimilated within Europe. These results point to a significant role for the conversion of women in the formation of Ashkenazi communities, and provide the foundation for a detailed reconstruction of Ashkenazi genealogical history. PMID:24104924

  8. Cranial injuries as evidence of violence in prehistoric southern California.

    PubMed

    Walker, P L

    1989-11-01

    Crania from the Channel Island area of southern California were examined for evidence of traumatic injuries. Well-healed depressed fractures in the outer table of the cranial vault are common in skeletal remains from the northern Channel Islands (18.56% n = 598) but rare in those from the mainland coast (7.5% n = 146). This prevalence of traumatic injuries among the islanders may be a result of intense competition over resources in a geographically circumscribed environment. The frequency of cranial injuries increases significantly between the early and late prehistoric periods on the Channel Islands. This temporal variation appears to reflect changes in patterns of violence associated with population growth and environmental instability.

  9. Mussel remains from prehistoric salt works, clarke county, Alabama

    USGS Publications Warehouse

    McGregor, S.W.; Dumas, A.A.

    2010-01-01

    Archaeological research at salt springs in Clarke County, AL (Tombigbee River drainage), documented bivalve mollusk exploitation by late prehistoric American Indians. A total of 582 valves representing 19 species of freshwater mussels (Unionidae) and an estuarine clam (Mactridae) from the Lower Salt Works Site (ca. A.D. 900-1550) and 41 valve fragments representing 6 mussel species from the Stimpson Site (ca. A.D. 1200-1550) were documented. The Lower Salt Works fauna was dominated numerically by Fusconaia ebena and Quadrula asperata, the dominant species reported during recent local surveys. The mussel species represented are known from medium to large streams in sand and gravel habitats and include four federally protected species and other species of conservation concern in Alabama. Results offer comparative data for other archaeological and ecological studies in the region.

  10. Prehistoric Packrats Piled Up Clues to Climate Change

    USGS Publications Warehouse

    Cole, Kenneth L.

    2008-01-01

    Scientists from the U.S. Geological Survey and Northern Arizona University studying climate change in the Southwestern United States are getting a helping hand?or would that be paw??from prehistoric packrats. By hoarding parts of animals and plants, including seeds and leaves, in garbage piles or ?middens,? these bushy-tailed rodents preserved crucial ecological and environmental information about the past. From these middens, scientists are able to reconstruct plant communities and natural systems from as long ago as 50,000 years. The contents of middens allow scientists to understand how ecosystems responded to rapid, large-scale climate changes of the past. The insights gained from midden research could offer clues to future changes driven by rapid climate shifts.

  11. Direct chemical evidence for widespread dairying in prehistoric Britain

    PubMed Central

    Copley, M. S.; Berstan, R.; Dudd, S. N.; Docherty, G.; Mukherjee, A. J.; Straker, V.; Payne, S.; Evershed, R. P.

    2003-01-01

    Domesticated animals formed an important element of farming practices in prehistoric Britain, a fact revealed through the quantity and variety of animal bone typically found at archaeological sites. However, it is not known whether the ruminant animals were raised purely for their tissues (e.g., meat) or alternatively were exploited principally for their milk. Absorbed organic residues from pottery from 14 British prehistoric sites were investigated for evidence of the processing of dairy products. Our ability to detect dairy fats rests on the observation that the δ13C values of the C18:0 fatty acids in ruminant dairy fats are ≈2.3‰ lower than in ruminant adipose fats. This difference can be ascribed to (i) the inability of the mammary gland to biosynthesize C18:0; (ii) the biohydrogenation of dietary unsaturated fatty acids in the rumen; and (iii) differences (i.e., 8.1‰) in the δ13C values of the plant dietary fatty acids and carbohydrates. The lipids from a total of 958 archaeological pottery vessels were extracted, and the compound-specific δ13C values of preserved fatty acids (C16:0 and C18:0) were determined via gas chromatography-combustion-isotope ratio mass spectrometry. The results provide direct evidence for the exploitation of domesticated ruminant animals for dairy products at all Neolithic, Bronze Age, and Iron Age settlements in Britain. Most significantly, studies of pottery from a range of key early Neolithic sites confirmed that dairying was a widespread activity in this period and therefore probably well developed when farming was introduced into Britain in the fifth millennium B.C. PMID:12574520

  12. Clarifying Prehistoric Parasitism from a Complementary Morphological and Molecular Approach.

    PubMed

    Cleeland, Lauren M; Reichard, Mason V; Tito, Raul Y; Reinhard, Karl J; Lewis, Cecil M

    2013-07-01

    This paper reports an approach to the identification of prehistoric parasitic infection, which integrates traditional morphological methods with molecular methods. The approach includes the strengths of each method while mitigating the limitations. Demonstrating the efficacy of this approach, we provide a case study from a 1,400 year old desiccated fecal sample from La Cueva de los Muertos Chiquitos, archaeological site, near Rio Zape, Durango, Mexico. Traditionally prepared microscope slides were processed via microscopy and tentative ascarids were identified. Information regarding the parasites' developmental stage was recorded. DNA was then extracted directly from the slide material. From this DNA extract, a small segment of the 18S ribosomal RNA gene variant that is specific to Ascaris, and its phylogenetically close relatives, was targeted for PCR amplification and sequencing. Phylogenetic analysis of the DNA sequence best matched a member of physalopterids, rather than ascarids, with a single exception of a match to Contracaecum spiculigerum. Subsequent extractions, amplifications and sequencing of the original rehydrated coprolite material confirmed these results. The C. spiculigerum sequence represented a phylogenetic anomaly and subsequent analysis determined the sequence was an error in the BLAST database, likely attributable to misidentification of juvenile specimens prior to sequencing and submission. Physaloptera are a difficult genus to identify morphologically and can carry major health burdens. They may be underreported in humans, in part, because of morphological similarities to the more common human parasites belonging to ascarids. We conclude that integrating traditional morphological methods with molecular methods can help resolve this issue, in both contemporary and prehistoric populations.

  13. Clarifying Prehistoric Parasitism from a Complementary Morphological and Molecular Approach

    PubMed Central

    Cleeland, Lauren M.; Reichard, Mason V.; Tito, Raul Y.; Reinhard, Karl J.; Lewis, Cecil M.

    2013-01-01

    This paper reports an approach to the identification of prehistoric parasitic infection, which integrates traditional morphological methods with molecular methods. The approach includes the strengths of each method while mitigating the limitations. Demonstrating the efficacy of this approach, we provide a case study from a 1,400 year old desiccated fecal sample from La Cueva de los Muertos Chiquitos, archaeological site, near Rio Zape, Durango, Mexico. Traditionally prepared microscope slides were processed via microscopy and tentative ascarids were identified. Information regarding the parasites’ developmental stage was recorded. DNA was then extracted directly from the slide material. From this DNA extract, a small segment of the 18S ribosomal RNA gene variant that is specific to Ascaris, and its phylogenetically close relatives, was targeted for PCR amplification and sequencing. Phylogenetic analysis of the DNA sequence best matched a member of physalopterids, rather than ascarids, with a single exception of a match to Contracaecum spiculigerum. Subsequent extractions, amplifications and sequencing of the original rehydrated coprolite material confirmed these results. The C. spiculigerum sequence represented a phylogenetic anomaly and subsequent analysis determined the sequence was an error in the BLAST database, likely attributable to misidentification of juvenile specimens prior to sequencing and submission. Physaloptera are a difficult genus to identify morphologically and can carry major health burdens. They may be underreported in humans, in part, because of morphological similarities to the more common human parasites belonging to ascarids. We conclude that integrating traditional morphological methods with molecular methods can help resolve this issue, in both contemporary and prehistoric populations. PMID:23645967

  14. Huge Erratic Boulders in Tonga Deposited by a Prehistoric Tsunami

    NASA Astrophysics Data System (ADS)

    Frohlich, C.; Hornbach, M. J.; Taylor, F. W.; Shen, C.; Moala, '; Morton, A. E.

    2008-12-01

    Along some coastlines there exist erratic boulders apparently emplaced by tsunamis or cyclonic storms. Evaluating their origin and time of emplacement provides crucial information constraining the frequency, severity and location of coastal hazards. Here we describe seven large coral limestone boulders near the village of Fahefa on Tongatapu, Southwest Pacific, apparently emplaced by a prehistoric tsunami. These boulders all lie 10-20m above sea level and above any possible source; all are 100-400 m from the present shoreline; 230Th ages indicate that all were in place during the last interglacial sea-level highstand ~120-130 ka; thus the boulders must have been emplaced either within the Holocene or ~120 ka. The largest boulder, with dimensions of 15 m x 11 m x 9 m, is ~20 times more massive than any reported boulders emplaced by historically documented storms and may be the largest known tsunami/storm erratic worldwide situated above its source. We perform computer simulations to assess whether tsunamis produced by earthquakes, undersea landslides, or volcanoes could emplace the Fahefa boulders. These indicate that either a volcanic flank collapse along the Tofua arc about 30-40 km to the southwest, or undersea landslides on the submarine slopes of Tongatapu could be responsible; either could explain why similar large erratic boulders aren't found elsewhere in Tonga. This study demonstrates that small (< 1 km3) submarine slope failures may, under favorable conditions, generate locally large tsunamis. The Fahefa boulders occur in an easily accessible, well-studied, and well-populated area yet were unknown to the scientific community until recently. This suggests that in other locations, systematic searches for erratic boulders and other tsunami deposits might provide new information for assessing the size and extent of prehistoric tsunamis.

  15. Human induced prehistoric and historical soil erosion and landscape development in Southwestern USA

    NASA Astrophysics Data System (ADS)

    Dotterweich, Markus; Ivester, Andrew H.; Hanson, Paul R.; Daniel, Larsen; Dye, David H.; Foster, Thomas H., II

    2015-04-01

    The significance of soil erosion due to pre-historic land use and possible feedback mechanisms had been hardly recognized in the Southeastern USA. Here, the agricultural practices only began in the second half of the Holocene. Sedentary hunters and gatherers started to domesticate squash and sunflowers. Associated with the expansion of maize cultivation in the Mississippian period between AD 800 and 1100, significant forest clearings took place on the river floodplains. During this time, central settlements with up to 30,000 residences existed and the surrounding ridge and furrow fields extended to up to 30 ha. It is still open to question why these groups already declined in the 14/15th centuries already before the arrival of the Europeans. However, around AD 1540 the conquistador de Soto still reports extended fields with intensive cultivation of maize in the uplands of Northern Mississippi. Despite of this intensive land use by Native Americans, current research gives no indication that these activities had any significant impact on river channel form. Also, no clear evidence exists for distinct channel change occurring in response to any sort of middle Holocene Hypsithermal, Medieval warm period, or the Little Ice Age. We will present results of a project which aims to explore erosion forms, colluvial sediments and buried soils in selected 0-order and 1st-order watersheds in the southeastern USA in order to gain, solidify, and evaluate general data on soil erosion during the Native American land use period and its respective long-term effects on the environment. This will be achieved by 1) recording the stratigraphy of colluvial and alluvial sediments and buried soils, 2) mapping the extent of erosional and colluvial forms, 3) analyzing chemical and physical soil and sediment properties, 4) establishing chronological control using various dating techniques including radiocarbon and OSL dating, and 5) quantifying soil erosion using hillslope sediments. The

  16. Regional, holocene records of the human dimension of global change: sea-level and land-use change in prehistoric Mexico

    NASA Astrophysics Data System (ADS)

    Sluyter, Andrew

    1997-02-01

    Regional, Holocene records hold particular relevance for understanding the reciprocal nature of global environmental change and one of its major human dimensions: "sustainable agriculture", i.e., food production strategies which entail fewer causes of and are less susceptible to environmental change. In an epoch of accelerating anthropogenic transformation, those records reveal the protracted regional causes and consequences of change (often agricultural) in the global system as well as informing models of prehistoric, intensive agriculture which, because of long tenures and high productivities, suggest strategies for sustainable agricultural in the present. This study employs physiographic analysis and the palynological, geochemical record from cores of basin fill to understand the reciprocal relation between environmental and land-use change in the Gulf of Mexico tropical lowland, focusing on a coastal basin sensitive to sea-level change and containing vestiges of prehistoric settlement and wetland agriculture. Fossil pollen reveals that the debut of maize cultivation in the Laguna Catarina watershed dates to ca. 4100 BC, predating the earliest evidence for that cultivar anywhere else in the lowlands of Middle America. Such an early date for a cultivar so central to Neotropical agroecology and environmental change, suggests the urgency of further research in the study region. Moreover, the longest period of continuous agriculture in the basin lasted nearly three millennia (ca. 2400 BC-AD 550) despite eustatic sea-level rise. Geochemical fluxes reveal the reciprocity between land-use and environmental change: slope destabilization, basin aggradation, and eutrophication. The consequent theoretical implications pertain to both applied and basic research. Redeploying ancient agroecologies in dynamic environments necessitates reconstructing the changing operational contexts of putative high productivity and sustainability. Adjusting land use in the face of global

  17. Pollen diagrams and prehistoric fields: the case of Bronze Age Haarlem, the Netherlands.

    PubMed

    Bakels

    2000-05-01

    The excavation of a Bronze Age field surrounded by peat in the vicinity of the Dutch town of Haarlem afforded a good opportunity to study the pollen rain released by such prehistoric fields. Pollen analysis of a core obtained from a peat deposit at a distance of 10m from the field's border revealed only a weak signal of a possible field. The conclusion is that the presence of prehistoric fields is difficult to detect by means of pollen analysis alone.

  18. Irrigated Agriculture, Saudi Arabia

    NASA Image and Video Library

    1990-01-20

    In Saudi Arabia, center-pivot, swing-arm irrigated agriculture complexes such as the one imaged at Jabal Tuwayq (20.5N, 45.0 E) extract deep fossil water reserves to achieve food crop production self sufficiency in this desert environment. The significance of the Saudi expanded irrigated agriculture is that the depletion of this finite water resource is a short term solution to a long term need that will still exist when the water has been extracted.

  19. Irrigated Agriculture, Saudi Arabia

    NASA Technical Reports Server (NTRS)

    1990-01-01

    In Saudi Arabia, center-pivot, swing-arm irrigated agriculture complexes such as the one imaged at Jabal Tuwayq (20.5N, 45.0 E) extract deep fossil water reserves to achieve food crop production self sufficiency in this desert environment. The significance of the Saudi expanded irrigated agriculture is that the depletion of this finite water resource is a short term solution to a long term need that will still exist when the water has been extracted.

  20. Halo Star Lithium Depletion

    SciTech Connect

    Pinsonneault, M. H.; Walker, T. P.; Steigman, G.; Narayanan, Vijay K.

    1999-12-10

    The depletion of lithium during the pre-main-sequence and main-sequence phases of stellar evolution plays a crucial role in the comparison of the predictions of big bang nucleosynthesis with the abundances observed in halo stars. Previous work has indicated a wide range of possible depletion factors, ranging from minimal in standard (nonrotating) stellar models to as much as an order of magnitude in models that include rotational mixing. Recent progress in the study of the angular momentum evolution of low-mass stars permits the construction of theoretical models capable of reproducing the angular momentum evolution of low-mass open cluster stars. The distribution of initial angular momenta can be inferred from stellar rotation data in young open clusters. In this paper we report on the application of these models to the study of lithium depletion in main-sequence halo stars. A range of initial angular momenta produces a range of lithium depletion factors on the main sequence. Using the distribution of initial conditions inferred from young open clusters leads to a well-defined halo lithium plateau with modest scatter and a small population of outliers. The mass-dependent angular momentum loss law inferred from open cluster studies produces a nearly flat plateau, unlike previous models that exhibited a downward curvature for hotter temperatures in the 7Li-Teff plane. The overall depletion factor for the plateau stars is sensitive primarily to the solar initial angular momentum used in the calibration for the mixing diffusion coefficients. Uncertainties remain in the treatment of the internal angular momentum transport in the models, and the potential impact of these uncertainties on our results is discussed. The 6Li/7Li depletion ratio is also examined. We find that the dispersion in the plateau and the 6Li/7Li depletion ratio scale with the absolute 7Li depletion in the plateau, and we use observational data to set bounds on the 7Li depletion in main-sequence halo

  1. Prehistoric Agricultural Communities in West Central Alabama. Volume 1. Excavations in the Lubbub Creek Archaeological Locality.

    DTIC Science & Technology

    1983-01-01

    Southeast? If we take the broad position that theory and expectation condition what we see as data, what we see as important, then contemporary...clearly in the present, equipped with and guided by concepts and theories from the historical sciences, human biology, and ecology. Its authors employ...other hand saw this tract of land as a natural repository for the material remains left by uncounted generations of Native Americans. There was evidence

  2. Transportation, integration, facilitation: Prehistoric trail networks of the Western Papagueria

    NASA Astrophysics Data System (ADS)

    White, Devin Alan

    This project used many sources of remotely sensed data, digital image analysis methods, advanced geospatial predictive modeling, and traditional archaeological survey to locate, document, contextualize, and interpret over one hundred prehistoric trails and associated networks in the Western Papagueria region of the North American Southwest in order to gain insight into how several landscapes within the region were used in the past. While a traditional culture history of the region suggests that the landscapes would have collectively been used primarily as a corridor for the transportation of exotic materials such as marine shell and salt from the Gulf of California to the Phoenix Basin and other parts of the Southwest, research has shown that the landscapes cannot be treated as a functional monolith. They exhibit a high degree of sub-regional variation motivated by strong local intra-community ties and sacred/ritual concerns in addition to energy-efficient, long distance travel motivated by exchange. This finding further strengthens current thinking related to the settlement of and regional interactions within the Western Papagueria during prehistory, one that continues to highlight its importance as a trade and transportation corridor, but also supports the idea of an indigenous semi-sedentary population that was focused inwards on fulfilling its own unique set of social, economic, and ideological needs.

  3. [Teeth size reduction in the prehistoric populations in Serbia].

    PubMed

    Pajević, Tina; Sessa, Tijana; Juloski, Jovana; Glišić, Branislav

    2012-01-01

    Anthropological studies show craniofacial changes with a reduction in teeth size during evolution of the human population. The objective was to measure and compare the sizes of teeth in the population of the Mesolithic-Neolithic sites in the Iron Gate Gorge and the population from the Early Bronze Age site of Mokrin. The study included teeth without advanced wear near the pulp. The material was divided according to the site of the skeletal population in two groups. Group 1 comprised 107 teeth from the Mesolithic-Neolithic sites Lepenski Vir and Vlasac. Group 2 included 158 teeth from the Mokrin graveyard dated in the Early Bronze Age. The mesio-distal diameter was measured in all teeth, while the vestibulo-oral diameter was measured in the molars only. Using the two-factor analysis of variance, the influence of sex, site and their interaction on the size of the teeth were investigated. The vestibulo-oral diameter of the upper third molar was significantly higher in males compared to females. The comparison between the groups showed that the vestibulooral diameter of the lower first molar was significantly higher in group 1. The present difference in teeth size indicates the existence of reduction during the prehistoric times. However, the time period between the populations studied is probably too short to be manifested on a large number of teeth.

  4. Basalt Pb isotope analysis and the prehistoric settlement of Polynesia.

    PubMed

    Weisler, M I; Woodhead, J D

    1995-03-14

    The prehistoric settlement of the Pacific Ocean has intrigued scholars and stimulated anthropological debate for the past two centuries. Colonized over a few millennia during the mid to late Holocene, the islands of the Pacific--displaying a wide diversity of geological and biotic variability--provided the stage for endless "natural experiments" in human adaptation. Crucial to understanding the evolution and transformation of island societies is documenting the relative degree of interisland contacts after island colonization. In the western Pacific, ideal materials for archaeologically documenting interisland contact--obsidian, pottery, and shell ornaments--are absent or of limited geographic distribution in Polynesia. Consequently, archaeologists have relied increasingly on fine-grained basalt artifacts as a means for documenting colonization routes and subsequent interisland contacts. Routinely used x-ray fluorescence characterization of oceanic island basalt has some problems for discriminating source rocks and artifacts in provenance studies. The variation in trace and major element abundances is largely controlled by near-surface magma-chamber processes and is broadly similar between most oceanic islands. We demonstrate that Pb isotope analysis accurately discriminates rock source and is an excellent technique for charting the scale, frequency, and temporal span of imported fine-grained basalt artifacts found throughout Polynesia. The technique adds another tool for addressing evolutionary models of interaction, isolation, and cultural divergence in the eastern Pacific.

  5. Volcanic tsunamis and prehistoric cultural transitions in Cook Inlet, Alaska

    USGS Publications Warehouse

    Beget, J.; Gardner, C.; Davis, K.

    2008-01-01

    The 1883 eruption of Augustine Volcano produced a tsunami when a debris avalanche traveled into the waters of Cook Inlet. Older debris avalanches and coeval paleotsunami deposits from sites around Cook Inlet record several older volcanic tsunamis. A debris avalanche into the sea on the west side of Augustine Island ca. 450??years ago produced a wave that affected areas 17??m above high tide on Augustine Island. A large volcanic tsunami was generated by a debris avalanche on the east side of Augustine Island ca. 1600??yr BP, and affected areas more than 7??m above high tide at distances of 80??km from the volcano on the Kenai Peninsula. A tsunami deposit dated to ca. 3600??yr BP is tentatively correlated with a southward directed collapse of the summit of Redoubt Volcano, although little is known about the magnitude of the tsunami. The 1600??yr BP tsunami from Augustine Volcano occurred about the same time as the collapse of the well-developed Kachemak culture in the southern Cook Inlet area, suggesting a link between volcanic tsunamis and prehistoric cultural changes in this region of Alaska. ?? 2008 Elsevier B.V.

  6. Y chromosomes of prehistoric people along the Yangtze River.

    PubMed

    Li, Hui; Huang, Ying; Mustavich, Laura F; Zhang, Fan; Tan, Jing-Ze; Wang, Ling-E; Qian, Ji; Gao, Meng-He; Jin, Li

    2007-11-01

    The ability to extract mitochondrial and nuclear DNA from ancient remains has enabled the study of ancient DNA, a legitimate field for over 20 years now. Recently, Y chromosome genotyping has begun to be applied to ancient DNA. The Y chromosome haplogroup in East Asia has since caught the attention of molecular anthropologists, as it is one of the most ethnic-related genetic markers of the region. In this paper, the Y chromosome haplogroup of DNA from ancient East Asians was examined, in order to genetically link them to modern populations. Fifty-six human remains were sampled from five archaeological sites, primarily along the Yangtze River. Strict criteria were followed to eliminate potential contamination. Five SNPs from the Y chromosome were successfully amplified from most of the samples, with at least 62.5% of the samples belonging to the O haplogroup, similar to the frequency for modern East Asian populations. A high frequency of O1 was found in Liangzhu Culture sites around the mouth of the Yangtze River, linking this culture to modern Austronesian and Daic populations. A rare haplogroup, O3d, was found at the Daxi site in the middle reaches of the Yangtze River, indicating that the Daxi people might be the ancestors of modern Hmong-Mien populations, which show only small traces of O3d today. Noticeable genetic segregation was observed among the prehistoric cultures, demonstrating the genetic foundation of the multiple origins of the Chinese Civilization.

  7. Basalt Pb isotope analysis and the prehistoric settlement of Polynesia.

    PubMed Central

    Weisler, M I; Woodhead, J D

    1995-01-01

    The prehistoric settlement of the Pacific Ocean has intrigued scholars and stimulated anthropological debate for the past two centuries. Colonized over a few millennia during the mid to late Holocene, the islands of the Pacific--displaying a wide diversity of geological and biotic variability--provided the stage for endless "natural experiments" in human adaptation. Crucial to understanding the evolution and transformation of island societies is documenting the relative degree of interisland contacts after island colonization. In the western Pacific, ideal materials for archaeologically documenting interisland contact--obsidian, pottery, and shell ornaments--are absent or of limited geographic distribution in Polynesia. Consequently, archaeologists have relied increasingly on fine-grained basalt artifacts as a means for documenting colonization routes and subsequent interisland contacts. Routinely used x-ray fluorescence characterization of oceanic island basalt has some problems for discriminating source rocks and artifacts in provenance studies. The variation in trace and major element abundances is largely controlled by near-surface magma-chamber processes and is broadly similar between most oceanic islands. We demonstrate that Pb isotope analysis accurately discriminates rock source and is an excellent technique for charting the scale, frequency, and temporal span of imported fine-grained basalt artifacts found throughout Polynesia. The technique adds another tool for addressing evolutionary models of interaction, isolation, and cultural divergence in the eastern Pacific. PMID:7892194

  8. Depleted Uranium: Technical Brief

    EPA Pesticide Factsheets

    This technical brief provides accepted data and references to additional sources for radiological and chemical characteristics, health risks and references for both the monitoring and measurement, and applicable treatment techniques for depleted uranium.

  9. Battery depletion monitor

    SciTech Connect

    Lee, Y.S.

    1982-01-26

    A cmos inverter is used to compare pacemaker battery voltage to a referenced voltage. When the reference voltage exceeds the measured battery voltage, the inverter changes state to indicate battery depletion.

  10. Addressing Ozone Layer Depletion

    EPA Pesticide Factsheets

    Access information on EPA's efforts to address ozone layer depletion through regulations, collaborations with stakeholders, international treaties, partnerships with the private sector, and enforcement actions under Title VI of the Clean Air Act.

  11. Theme: Agricultural Literacy about Agriculture.

    ERIC Educational Resources Information Center

    Frick, Martin J.; And Others

    1996-01-01

    Includes "'Sharing' the Gospel According to Agriculture!" (Frick); "Agricultural Literacy: An Integrated Content and Partnership Approach" (Parmley et al.); "Idaho Agriculture in the Classroom" (Pals, Waitley); "Middle School Agricultural Education" (Moore, Violett); "Agricultural Communication"…

  12. Crafting a new science: defining paleoanthropology and its relationship to prehistoric archaeology, 1860-1890.

    PubMed

    Goodrum, Matthew R

    2014-12-01

    Paleoanthropology emerged as a science during the late nineteenth century. The discovery of prehistoric artifacts in Pleistocene deposits soon led to the excavation of fossilized human bones. The archaeologists and geologists who unearthed them were primarily concerned with determining whether the human fossils and the artifacts found with them actually dated from the Pleistocene, thus offering evidence for the geological antiquity of humans. Prehistoric archaeologists reconstructed the way of life of prehistoric peoples through the artifacts found, while anthropologists examined the human fossils. They wanted primarily to identify the races of prehistoric humans. It was within this context that French anthropologists began to use the term "paléo-anthropologie" to refer to a new scientific discipline devoted to the study of prehistoric human races and human paleontology. This essay examines how paleoanthropology was defined as a science during the 1870s and 1880s. It shows that a tension existed between the objectives and methods of archaeologists and anthropologists. Paul Topinard criticized archaeologists and argued that a new type of scientist; the paleoanthropologist trained in anatomy or zoology, was needed to study human fossils properly.

  13. Anthropogenic effects on soil quality in ancient terraced agricultural fields of Chihuahua, Mexico

    USDA-ARS?s Scientific Manuscript database

    Agricultural soil quality was investigated in ancient field systems near Casas Grandes (also known as Paquimé), one of the largest and most complex prehistoric settlements in the North American Southwest. This research was completed as part of an interdisciplinary study of the anthropogenic ecology...

  14. Groundwater depletion embedded in international food trade.

    PubMed

    Dalin, Carole; Wada, Yoshihide; Kastner, Thomas; Puma, Michael J

    2017-03-29

    Recent hydrological modelling and Earth observations have located and quantified alarming rates of groundwater depletion worldwide. This depletion is primarily due to water withdrawals for irrigation, but its connection with the main driver of irrigation, global food consumption, has not yet been explored. Here we show that approximately eleven per cent of non-renewable groundwater use for irrigation is embedded in international food trade, of which two-thirds are exported by Pakistan, the USA and India alone. Our quantification of groundwater depletion embedded in the world's food trade is based on a combination of global, crop-specific estimates of non-renewable groundwater abstraction and international food trade data. A vast majority of the world's population lives in countries sourcing nearly all their staple crop imports from partners who deplete groundwater to produce these crops, highlighting risks for global food and water security. Some countries, such as the USA, Mexico, Iran and China, are particularly exposed to these risks because they both produce and import food irrigated from rapidly depleting aquifers. Our results could help to improve the sustainability of global food production and groundwater resource management by identifying priority regions and agricultural products at risk as well as the end consumers of these products.

  15. Groundwater depletion embedded in international food trade

    NASA Astrophysics Data System (ADS)

    Dalin, Carole; Wada, Yoshihide; Kastner, Thomas; Puma, Michael J.

    2017-03-01

    Recent hydrological modelling and Earth observations have located and quantified alarming rates of groundwater depletion worldwide. This depletion is primarily due to water withdrawals for irrigation, but its connection with the main driver of irrigation, global food consumption, has not yet been explored. Here we show that approximately eleven per cent of non-renewable groundwater use for irrigation is embedded in international food trade, of which two-thirds are exported by Pakistan, the USA and India alone. Our quantification of groundwater depletion embedded in the world’s food trade is based on a combination of global, crop-specific estimates of non-renewable groundwater abstraction and international food trade data. A vast majority of the world’s population lives in countries sourcing nearly all their staple crop imports from partners who deplete groundwater to produce these crops, highlighting risks for global food and water security. Some countries, such as the USA, Mexico, Iran and China, are particularly exposed to these risks because they both produce and import food irrigated from rapidly depleting aquifers. Our results could help to improve the sustainability of global food production and groundwater resource management by identifying priority regions and agricultural products at risk as well as the end consumers of these products.

  16. Remote Sensing for Detection of Prehistoric Landscape Use in NW Arizona, USA

    NASA Astrophysics Data System (ADS)

    Buck, P.; Sabol, D. E.

    2012-12-01

    Optimal maize field locations possibly used by prehistoric agriculturalists in the Mt. Trumbull portion of the Colorado Plateau in NW AZ were modeled using remotely sensed data and ground based observations. Over 400 prehistoric archaeological sites have been recorded in the study area; in some areas site density is ~120 sites/mi2, including many 1-2 room structures traditionally referred to as "field houses" that archaeologists have long assumed were located on or immediately adjacent to maize fields. Other site types are larger C-shaped pueblos with up to 20 rooms and somewhat smaller multi room structures. We collected and used ground-based field measurements and satellite image data from ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) to produce GIS layers to predict ancient maize fields and compare these with known "field house" sites. Input data layers for the model included early spring maximum solar illumination, surface gradient, surface radiant temperature, water surface flow collection, water infiltration, and soil type. We constructed 2 types of optimality models: "restrictive" (or classification) models and "fuzzy logic" (or grouping) models. Highest values were assigned to pixels with more surface water, warmer temperature, better soils, etc. and then assigned a color for display. Analyses of patterns for the "green" restrictive model shows a disproportionate number of large sites found within 200 m of the green optimal zone; for the yellow optimal zone there is a statistically significant relationship between larger sites and the yellow zones at 100 m or less. For the blue fuzzy logic model, again there is a strong relationship between the number of large sites and a blue zone both at 100 m and 200 m distances. So-called "field houses" are not located preferentially close to our optimal areas. Rather, there is a clear preference for larger sites to be found closer to optimal areas. Using the proportion of site types from the

  17. Radiocarbon-dating and ancient DNA reveal rapid replacement of extinct prehistoric penguins

    NASA Astrophysics Data System (ADS)

    Rawlence, Nicolas J.; Perry, George L. W.; Smith, Ian W. G.; Scofield, R. Paul; Tennyson, Alan J. D.; Matisoo-Smith, Elizabeth A.; Boessenkool, Sanne; Austin, Jeremy J.; Waters, Jonathan M.

    2015-03-01

    Prehistoric faunal extinctions dramatically reshaped biological assemblages around the world. However, the timing of such biotic shifts is often obscured by the fragmentary nature and limited temporal resolution of fossil records. We use radiocarbon-dating and ancient-DNA analysis of prehistoric (ca A.D. 1450-1834) Megadyptes penguin specimens to assess the time-frame of biological turnover in coastal New Zealand following human settlement. These data suggest that the final extirpation of the endemic Megadyptes waitaha, and subsequent replacement by the previously sub-Antarctic-limited Megadyptes antipodes, likely occurred within a narrow temporal window (e.g. a century or less). This transition represents one of the most rapid prehistoric faunal turnover events documented, and is likely linked to human demographic and cultural transitions during the 15th Century. Our results suggest that anthropogenic forces can trigger rapid biogeographic shifts.

  18. Cholesterol depletion induces autophagy

    SciTech Connect

    Cheng, Jinglei; Ohsaki, Yuki; Tauchi-Sato, Kumi; Fujita, Akikazu; Fujimoto, Toyoshi . E-mail: tfujimot@med.nagoya-u.ac.jp

    2006-12-08

    Autophagy is a mechanism to digest cells' own components, and its importance in many physiological and pathological processes is being recognized. But the molecular mechanism that regulates autophagy is not understood in detail. In the present study, we found that cholesterol depletion induces macroautophagy. The cellular cholesterol in human fibroblasts was depleted either acutely using 5 mM methyl-{beta}-cyclodextrin or 10-20 {mu}g/ml nystatin for 1 h, or metabolically by 20 {mu}M mevastatin and 200 {mu}M mevalonolactone along with 10% lipoprotein-deficient serum for 2-3 days. By any of these protocols, marked increase of LC3-II was detected by immunoblotting and by immunofluorescence microscopy, and the increase was more extensive than that caused by amino acid starvation, i.e., incubation in Hanks' solution for several hours. The induction of autophagic vacuoles by cholesterol depletion was also observed in other cell types, and the LC3-positive membranes were often seen as long tubules, >50 {mu}m in length. The increase of LC3-II by methyl-{beta}-cyclodextrin was suppressed by phosphatidylinositol 3-kinase inhibitors and was accompanied by dephosphorylation of mammalian target of rapamycin. By electron microscopy, autophagic vacuoles induced by cholesterol depletion were indistinguishable from those seen after amino acid starvation. These results demonstrate that a decrease in cholesterol activates autophagy by a phosphatidylinositol 3-kinase-dependent mechanism.

  19. EVIDENCE FOR THREE MODERATE TO LARGE PREHISTORIC HOLOCENE EARTHQUAKES NEAR CHARLESTON, S. C.

    USGS Publications Warehouse

    Weems, Robert E.; Obermeier, Stephen F.; Pavich, Milan J.; Gohn, Gregory S.; Rubin, Meyer; Phipps, Richard L.; Jacobson, Robert B.

    1986-01-01

    Earthquake-induced liquefaction features (sand blows), found near Hollywood, S. C. , have yielded abundant clasts of humate-impregnated sand and sparse pieces of wood. Radiocarbon ages for the humate and wood provide sufficient control on the timing of the earthquakes that produced the sand blows to indicate that at least three prehistoric liquefaction-producing earthquakes (m//b approximately 5. 5 or larger) have occurred within the last 7,200 years. The youngest documented prehistoric earthquake occurred around 800 A. D. A few fractures filled with virtually unweathered sand, but no large sand blows, can be assigned confidently to the historic 1886 Charleston earthquake.

  20. The association between Harris lines and enamel hypoplasia in prehistoric California Indians.

    PubMed

    McHenry, H M; Schulz, P D

    1976-05-01

    Hypoplastic defects of tooth enamel and Harris lines in the long bones have been heralded as potentially useful indicators of health conditions in prehistoric populations. Both result from temporary cessation of growth processes due to similar types of disease, malnutrition, or other metabolic insult. An association test for the first six years of life was conducted on a large series of prehistoric California Indians, using femora and canines from young adults. No significant association was found. This is ascribable to differences in etiology and stability.

  1. Dynamic Monitoring Reveals Motor Task Characteristics in Prehistoric Technical Gestures

    PubMed Central

    Pfleging, Johannes; Stücheli, Marius; Iovita, Radu; Buchli, Jonas

    2015-01-01

    . These results demonstrate that different gestures used in ‘common’ prehistoric tasks can be distinguished quantitatively based on their dynamic parameters. Future research needs to assess our ability to reconstruct these parameters from observed use-wear patterns. PMID:26284785

  2. Dynamic Monitoring Reveals Motor Task Characteristics in Prehistoric Technical Gestures.

    PubMed

    Pfleging, Johannes; Stücheli, Marius; Iovita, Radu; Buchli, Jonas

    2015-01-01

    . These results demonstrate that different gestures used in 'common' prehistoric tasks can be distinguished quantitatively based on their dynamic parameters. Future research needs to assess our ability to reconstruct these parameters from observed use-wear patterns.

  3. Assessing the prehistoric shoreline changes of the Mekong delta, Vietnam

    NASA Astrophysics Data System (ADS)

    Tamura, T.; Saito, Y.; Nguyen, V. L.; Ta, T. K. O.; Bateman, M. D.; Sato, A.

    2014-12-01

    The environment and sustainability of deltaic lowlands have been threatened by combined impacts of climate changes, human activities and land subsidence. The Mekong delta has also been disturbed by the construction of upstream river dams and fluvial dredging, and we have a limited knowledge of its morphodynamics response to fluctuations in Asian monsoons that governs the coastal sediment dynamics. In order to understand the recent shoreline changes of the Mekong delta, we attempted to reconstruct the prehistoric changes based on landform records and their chronology. Thirteen optically-stimulated luminescence (OSL) ages of chenier, a record of past shoreline, were obtained from the Soc Trang coastal plain, southwestern part of the delta. The OSL ages are younger than 2770 yr BP, and become younger seawards concordantly with the coastal progradation that cheniers document. The progradation rate has changed drastically; it was 8 m/yr, 31 m/yr, and 5 m/yr during periods of 2770-1370 yr BP, 1370-590 yr BP, and 590 yr BP to present, respectively. The rapid progradation during 1370-590 yr BP did not form cheniers, resulting in an extensive inter-ridge swale. Cheniers generally form in relations to erosion of muddy coast. The chenier distribution and drastic changes in progradation rate were resulted from fluctuations in relative importance of longshore sediment removal to seaward sediment accretion. Beach ridges in the Tra Vinh coastal plain, northeast of the Soc Trang, also indicate similar and synchronous fluctuations in the longshore sediment transport. The dominance of the longshore sediment transport after 590 yr BP is thought caused by the strengthened winter monsoon that drives the southwestward longshore current, which is possibly related to the beginning of the Little Ice Age. Many cheniers occur along the present shoreline in relation to the low progradation rate, and possibly some sporadic erosion after 590 yr BP. Some evidences have suggested that the winter

  4. A new approach for studying prehistoric herd management in arid areas: intra-tooth isotopic analyses of archaeological caprine from IranUne nouvelle approche pour l'étude de la gestion préhistorique des troupeaux en zones arides: analyses isotopiques intra-dentaires de caprinés archéologiques d'Iran

    NASA Astrophysics Data System (ADS)

    Bocherens, Hervé; Mashkour, Marjan; Billiou, Daniel; Pellé, Eric; Mariotti, André

    2001-01-01

    Carbon and oxygen isotopic variations in archaeological tooth enamel from Iran have been used to investigate prehistoric herd management. Oxygen isotopic variations in domestic caprines are more important than in wild equids, indicating a seasonal consumption of 18O-depleted drinking water. Since the plants consumed at the same time were partly C 4, it is presumed that the access to this 18O-depleted water was controlled by humans, and that the water came from wells or underground canalisations. This methodology is expected to provide valuable information on herd management in the past in arid areas.

  5. Depletion of Intense Fields

    NASA Astrophysics Data System (ADS)

    Seipt, D.; Heinzl, T.; Marklund, M.; Bulanov, S. S.

    2017-04-01

    The interaction of charged particles and photons with intense electromagnetic fields gives rise to multiphoton Compton and Breit-Wheeler processes. These are usually described in the framework of the external field approximation, where the electromagnetic field is assumed to have infinite energy. However, the multiphoton nature of these processes implies the absorption of a significant number of photons, which scales as the external field amplitude cubed. As a result, the interaction of a highly charged electron bunch with an intense laser pulse can lead to significant depletion of the laser pulse energy, thus rendering the external field approximation invalid. We provide relevant estimates for this depletion and find it to become important in the interaction between fields of amplitude a0˜1 03 and electron bunches with charges of the order of 10 nC.

  6. Prehistoric human impact on rainforest biodiversity in highland New Guinea.

    PubMed

    Haberle, Simon G

    2007-02-28

    In the highlands of New Guinea, the development of agriculture as an indigenous innovation during the Early Holocene is considered to have resulted in rapid loss of forest cover, a decrease in forest biodiversity and increased land degradation over thousands of years. But how important is human activity in shaping the diversity of vegetation communities over millennial time-scales? An evaluation of the change in biodiversity of forest habitats through the Late Glacial transition to the present in five palaeoecological sites from highland valleys, where intensive agriculture is practised today, is presented. A detailed analysis of the longest and most continuous record from Papua New Guinea is also presented using available biodiversity indices (palynological richness and biodiversity indicator taxa) as a means of identifying changes in diversity. The analysis shows that the collapse of key forest habitats in the highland valleys is evident during the Mid - Late Holocene. These changes are best explained by the adoption of new land management practices and altered disturbance regimes associated with agricultural activity, though climate change may also play a role. The implications of these findings for ecosystem conservation and sustainability of agriculture in New Guinea are discussed.

  7. The hydrology of prehistoric farming systems in a central Arizona ecotone

    NASA Technical Reports Server (NTRS)

    Gumerman, G. J.; Hanson, J. A.; Brew, D.; Tomoff, K.; Weed, C. S.

    1975-01-01

    The prehistoric land use and water management in the semi-arid Southwest was examined. Remote sensing data, geology, hydrology and biology are discussed along with an evaluation of remote sensing contributions, recommendations for applications, and proposed future remote sensing studies.

  8. Prehistoric occupation of the eastern desert, Egypt: a key to landform analysis

    SciTech Connect

    Gawarecki, S.L.; Hoffman, M.A.; Perry, S.K.

    1985-01-01

    Surface scatters of lithic artifacts on Quaternary faulted relict surfaces and terrace flights represent the first Prehistoric sites reported from the west bank, Gulf of Suez. These aid in analyzing the geomorphifc history of the Gulf, a Neogene rift valley. Diagnostic artifacts include Lower Palaeolithic choppers and Acheulean hand axes; Middle Palaeolithic Levallois flakes and points, denticulate scrapers, and a discoidal core; Late Palaeolithic blade and scrapers and blades; and a Neolithic tanged point, side scraper, and chipped axe. Tectonic and climatic changes are indicated by vertical distribution of Prehistoric sites. Similar artifact assemblages at different relative elevations on bedrock horsts imply laterally varying tectonic uplift rates. Large elevation differences between Middle and Late Palaeolithic-bearing alluvial terraces indicate rapid erosional landscape change. This allows tentative correlation of widely separated terrace flights and indicates the latest possible age of drainage abandonment. Considerable climatic amelioration would have been required for Prehistoric occupation of this arid region. Sites were probably situated above then-active drainages. Additionally, today's limited rainfall cannot account for the amount of erosion since Prehistoric occupation. Therefore, at least three pluvials, corresponding to the Lower, Middle, and Late Palaeolithic, are postulated; these apparently controlled both landscape development and human occupation of this marginal ecosystem. Archaeological analysis can thus be useful as a tool for semiquantitative evaluation of erosion cycles and uplift rates.

  9. [What do we know of nutrition of children and juveniles in prehistoric and early historic time?].

    PubMed

    Grimm, H

    1981-01-01

    News are added to Peiper's "chronicle of pediatrics" concerning nutrition of children and juveniles in prehistoric and early historic periods. This may make possible some conclusions about "paleonutrition". Items come from 15 exactly localised sites and 4 more vague defined regions from the neolithic period to 1000 A. D.

  10. Probable fijian origin of quartzose temper sands in prehistoric pottery from tonga and the marquesas.

    PubMed

    Dickinson, W R; Shutler, R

    1974-08-02

    Quartzose temper sands included within fired clay bodies of certain prehistoric potsherds from Tonga and the Marquesas have mineralogical compositions wholly different from those of indigenous sands that occur as temper in other potsherds from the same sites but are indistinguishable from sands in potsherds collected from the Rewa Delta of Viti Levu in Fiji.

  11. Prehistoric blood residues: detection on tool surfaces and identification of species of origin.

    PubMed

    Loy, T H

    1983-06-17

    Blood residues from several animal species have been discovered on the surfaces of chert, basalt, and obsidian prehistoric tools (1000 to 6000 years old) from open-air sites along the western coast and in the northern boreal forest of Canada. A screening test has been developed to detect residual blood. Hemoglobin has been crystallized from the residues, and the species of origin determined.

  12. Non-destructive provenance differentiation of prehistoric pigments by external PIXE

    NASA Astrophysics Data System (ADS)

    Beck, L.; Salomon, H.; Lahlil, S.; Lebon, M.; Odin, G. P.; Coquinot, Y.; Pichon, L.

    2012-02-01

    The elemental analysis of minerals/rocks has been often used for the determination of their geological origin. When these natural rocks were exploited by prehistoric civilizations as objects, weapons, or pigments, the composition of the minerals can provide information on the mobility, the exchanges and the interaction between groups of population. In this paper, we will present results obtained from archaeological samples of prehistoric pigments, mainly iron and manganese oxides. PIXE analysis has been applied to samples of the prehistoric cave "La grotte du Renne" in Arcy-sur-Cure, France (Chatelperronian, 38,000-34,000 BP). Because most of the archaeological objects are decorated or display some use marks, it is not possible to take samples. Consequently, we have used a non-destructive technique thanks to the external beam of AGLAE (C2RMF, Paris). In order to improve the limits of detection (LOD less than 10 ppm from Cu to Sb), a metal absorber has been placed on the X-ray detector to preferentially filter the Fe-K or Mn-K lines. Based on the quantitative analysis of major and trace elements, we have obtained groups of compositions corresponding to different geological sources. We demonstrate in this study that it is possible to extend PIXE analysis to the characterization of prehistoric pigments such as iron and manganese oxides for differentiating potential sources of pigments in archaeological contexts.

  13. Prehistoric (Chalcolithic) Eastern Mediterranean tsunami deposit identified offshore central Israel

    NASA Astrophysics Data System (ADS)

    Tyuleneva, Natalia; Braun, Yael; Suchkov, Igor; Goodman-Tchernov, Beverly

    2017-04-01

    The shallow shelf area ( 15-30 m water depth) offshore Israel, bears great potential for paleo-tsunami studies. It was shown in the course of previous research that in these offshore marine deposits, tsunami generated sedimentary layers can be well preserved and readily identified; unlike in onshore sedimentary sequences, which experience continuous exogenous natural and anthropogenic influence. A sediment core, 219 cm long, was obtained from 15.3 m water depth, in about 4 km north of Caesarea. Grain size at 1 cm interval as well as XRD and XRF analyses at coarser resolution were performed. Previously carried out research allowed correlation of two anomalous layers in this core with well described sediment sequences offshore Caesarea. These two events correspond best with the proposed events of 749 AD and 1500 BC. Identified unusual layers in this core bear certain set of proxies that are characteristic for tsunami generated deposits and easily distinguished from the local normal marine setting. The latter is characterized by three dominating mineralogical components, such as carbonaceous sand derived either from biogenic material, namely shell fragments or from eroded limestones and dolomites that outcrop the mountains to the east; siliciclastic quartz for the sand fraction and mineral smectite for the clays. The supply of the two latter terrigenous sedimentary components comes from the Nile River, which has been a stable and predominant source of sediments for the past 8 ka. The aim of this study is to characterize the earliest unusual sedimentary layer found down core between 191 and 211 cm. This layer was attributed to a tsunami-generated sedimentary sequence in the studied core. Absolute age determination based on 14C gave the time frame from 5.6 to 6 ka BP, making this event the oldest identified in the Eastern Mediterranean to date. This tsunami corresponds to the Chalcolithic ('Copper Age') cultural period of the region. Prehistoric age of these sediments

  14. Determining Prehistoric Mining Practices in Southeastern Europe Using Copper Isotopes

    NASA Astrophysics Data System (ADS)

    Powell, Wayne; Mathur, Ryan; Bankoff, H. Arthur; Bulatović, Aleksandar; Filipović, Vojislav

    2017-04-01

    Copper was first smelted from malachite at 5000 BCE in Serbia. There the Eneolithic (Copper Age) began with the production of small jewelry pieces and progressed to the casting of massive copper tools near its end, approximately 2000 years later. However, copper metallurgy in southeastern Europe ceased or significantly decreased in the later third millennium, several centuries before the Bronze Age began. Whether this metallurgical hiatus was the result a cultural shift or depletion of natural resources remains an ongoing subject of debate. It has been speculated that the marked reduction in metal production at the Eneolithic-Bronze Age transition was due to the exhaustion of surficial weathered oxide ores and the technical inability to smelt the underlying sulfide minerals. The behavior of copper isotopes in near-surface environments allows us to differentiate highly weathered oxide ores that occur at Earth's surface from non-weathered sulfide ores that occur at greater depth. The oxidation of copper generates fluids and associated minerals that are enriched in the 65Cu isotope. Thus, oxidative weathering of sulfide ores leads to the development of three stratified isotopic reservoirs for copper: 1) oxides above the water table that are enriched in 65Cu; 2) residual weathered sulfides minerals at the water table that are depleted in 65Cu; and 3) non-fractionated, non-weathered sulfide ore below the water table. And so, the transformative shift to sulfide-based metallurgy will be delineated by a significant decrease in δ65Cu in copper artifacts corresponding to the first use of 65Cu-depleted residual ore. The degree of variability of primary ore composition from numerable ore deposits would likely result in the overlap of copper isotope composition between populations of artifacts. Therefore, shifts in the mean copper isotope values and associated standard deviations would best reflect changes in ores use. A baseline value of -0.2‰ ±0.5 (1) was determined

  15. Spatial and temporal variations in prehistoric human settlement and their influencing factors on the south bank of the Xar Moron River, Northeastern China

    NASA Astrophysics Data System (ADS)

    Jia, Xin; Yi, Shuangwen; Sun, Yonggang; Wu, Shuangye; Lee, Harry F.; Wang, Lin; Lu, Huayu

    2016-05-01

    The West Liao River Basin is the hub of ancient civilizations as well as the birthplace of rain-fed agriculture in Northern China. In the present study, based on 276 archaeological sites on the south bank of the Xar Moron River, Northeastern China, we trace the changes in prehistoric cultures as well as the shifts in the spatial and temporal patterns of human settlement in the West Liao River Basin. Location information for those sites was obtained from fieldwork. Factors such as climate change, landform evolution of the Horqin Dunefield, and subsistence strategies practiced at the sites were extracted via the meta-analysis of published literature. Our results show that the Holocene Optimum promoted the emergence of Neolithic Culture on the south bank of the Xar Moron River. Monsoon failure might have caused the periodic collapse or transformation of prehistoric cultures at (6.5, 4.7, 3.9, and 3.0) kyr B.P., leaving spaces for new cultural types to develop after these gaps. The rise and fall of different cultures was also determined by subsistence strategies. The Xiaoheyan Culture, with mixed modes of subsistence, weakened after 4.7 kyr B.P., whereas the Upper Xiajiadian Culture, supported by sheep breeding, expanded after 3.0 kyr B.P. Global positioning system data obtained from the archaeological sites reveal that cultures with different subsistence strategies occupied distinct geographic regions. Humans who subsisted on hunting and gathering resided at higher altitudes during the Paleolithic Age (1074 m a.s.l.). Mixed subsistence strategies led humans to settle down at 600-1000 m a.s.l. in the Neolithic Age. Agricultural activities caused humans to migrate to 400-800 m a.s.l. in the early Bronze Age, whereas livestock production shifted human activities to 800-1200 m a.s.l. in the late Bronze Age.

  16. Spatial and temporal variations in prehistoric human settlement and their influencing factors on the south bank of the Xar Moron River, Northeastern China

    NASA Astrophysics Data System (ADS)

    Jia, Xin; Yi, Shuangwen; Sun, Yonggang; Wu, Shuangye; Lee, Harry F.; Wang, Lin; Lu, Huayu

    2017-03-01

    The West Liao River Basin is the hub of ancient civilizations as well as the birthplace of rain-fed agriculture in Northern China. In the present study, based on 276 archaeological sites on the south bank of the Xar Moron River, Northeastern China, we trace the changes in prehistoric cultures as well as the shifts in the spatial and temporal patterns of human settlement in the West Liao River Basin. Location information for those sites was obtained from fieldwork. Factors such as climate change, landform evolution of the Horqin Dunefield, and subsistence strategies practiced at the sites were extracted via the meta-analysis of published literature. Our results show that the Holocene Optimum promoted the emergence of Neolithic Culture on the south bank of the Xar Moron River. Monsoon failure might have caused the periodic collapse or transformation of prehistoric cultures at (6.5, 4.7, 3.9, and 3.0) kyr B.P., leaving spaces for new cultural types to develop after these gaps. The rise and fall of different cultures was also determined by subsistence strategies. The Xiaoheyan Culture, with mixed modes of subsistence, weakened after 4.7 kyr B.P., whereas the Upper Xiajiadian Culture, supported by sheep breeding, expanded after 3.0 kyr B.P. Global positioning system data obtained from the archaeological sites reveal that cultures with different subsistence strategies occupied distinct geographic regions. Humans who subsisted on hunting and gathering resided at higher altitudes during the Paleolithic Age (1074 m a.s.l.). Mixed subsistence strategies led humans to settle down at 600-1000 m a.s.l. in the Neolithic Age. Agricultural activities caused humans to migrate to 400-800 m a.s.l. in the early Bronze Age, whereas livestock production shifted human activities to 800-1200 m a.s.l. in the late Bronze Age.

  17. Depleted uranium management alternatives

    SciTech Connect

    Hertzler, T.J.; Nishimoto, D.D.

    1994-08-01

    This report evaluates two management alternatives for Department of Energy depleted uranium: continued storage as uranium hexafluoride, and conversion to uranium metal and fabrication to shielding for spent nuclear fuel containers. The results will be used to compare the costs with other alternatives, such as disposal. Cost estimates for the continued storage alternative are based on a life-cycle of 27 years through the year 2020. Cost estimates for the recycle alternative are based on existing conversion process costs and Capital costs for fabricating the containers. Additionally, the recycle alternative accounts for costs associated with intermediate product resale and secondary waste disposal for materials generated during the conversion process.

  18. Tank depletion flow controller

    DOEpatents

    Georgeson, Melvin A.

    1976-10-26

    A flow control system includes two bubbler tubes installed at different levels within a tank containing such as radioactive liquid. As the tank is depleted, a differential pressure transmitter monitors pressure differences imparted by the two bubbler tubes at a remote, shielded location during uniform time intervals. At the end of each uniform interval, balance pots containing a dense liquid are valved together to equalize the pressures. The resulting sawtooth-shaped signal generated by the differential pressure transmitter is compared with a second sawtooth signal representing the desired flow rate during each time interval. Variations in the two signals are employed by a control instrument to regulate flow rate.

  19. Depletion of intense fields

    NASA Astrophysics Data System (ADS)

    Bulanov, S. S.; Seipt, D.; Heinzl, T.; Marklund, M.

    2017-03-01

    The problem of backreaction of quantum processes on the properties of the background field still remains on the list of outstanding questions of high intensity particle physics. Usually, photon emission by an electron or positron, photon decay into electron-positron pairs in strong electromagnetic fields, or electron-positron pair production by such fields are described in the framework of the external field approximation. It is assumed that the external field has infinite energy and is not affected by these processes. However, the above-mentioned processes have a multi-photon nature, i.e., they occur with the absorption of a significant number of field photons. As a result, the interaction of an intense electromagnetic field with either a highly charged electron bunch or a fast growing population of electrons, positrons, and gamma photons (as in the case of an electromagnetic cascade) may lead to a depletion of the field energy, thus making the external field approximation invalid. Taking the multi-photon Compton process as an example, we estimate the threshold of depletion and find it to become significant at field strengths (a0˜103) and electron bunch charge of about tens of nC.

  20. Agriculture: Agriculture and Air Quality

    EPA Pesticide Factsheets

    Information on air emissions from agricultural practices, types of agricultural burning, air programs that may apply to agriculture, reporting requirements, and links to state and other federal air-quality information.

  1. Prehistoric extinction of birds on Mangaia, Cook Islands, Polynesia.

    PubMed Central

    Steadman, D W; Kirch, P V

    1990-01-01

    Mangaia (Cook Islands) consists of a weathered volcanic interior encircled by limestones known as the makatea. Excavations at Tangatatau Rockshelter (site MAN-44), located on the inner cliff of the makatea, produced a stratified sequence of Polynesian artifacts and faunal remains ranging from A.D. 1000-1100 to A.D. 1500-1600. Resident species of birds represented at MAN-44 include nine seabirds (at least three extirpated on Mangaia) and 12 land birds (eight extirpated or extinct). Seven of the extinct/extirpated land birds are confined to the site's four lowest stratigraphic zones, which represent the first 200-300 yr of human occupation at MAN-44. During this time, human exploitation of vertebrates switched from primarily native land birds to almost exclusively small reef fish, domesticates (chickens, pigs), and commensals (rats). Sediment cores from a lake 0.9 km from MAN-44 show clear palynological and stratigraphic signals of human presence on Mangaia, especially forest clearance of the volcanic interior, beginning at 1600 yr B.P. The rugged makatea must have provided a forest refuge for birds during the first 700 yr of human presence, after which Mangaians exploited the previously little used makatea because forest resources (trees, other plants, birds) had been depleted on the now badly eroded volcanic interior. MAN-44 is the oldest archaeological site known on Mangaia. Whether other species of birds were lost in the period of human activity that preceded occupation of MAN-44 remains to be seen. PMID:11607131

  2. Stimulated Emission Depletion Microscopy.

    PubMed

    Blom, Hans; Widengren, Jerker

    2017-06-14

    Despite its short history, diffraction-unlimited fluorescence microscopy techniques have already made a substantial imprint in the biological sciences. In this review, we describe how stimulated emission depletion (STED) imaging originally evolved, how it compares to other optical super-resolution imaging techniques, and what advantages it provides compared to previous golden-standards for biological microscopy, such as diffraction-limited optical microscopy and electron microscopy. We outline the prerequisites for successful STED imaging experiments, emphasizing the equally critical roles of instrumentation, sample preparation, and photophysics, and describe major evolving strategies for how to push the borders of STED imaging even further in life science. Finally, we provide examples of how STED nanoscopy can be applied, within three different fields with particular potential for STED imaging experiments: neuroscience, plasma membrane biophysics, and subcellular clinical diagnostics. In these areas, and in many more, STED imaging can be expected to play an increasingly important role in the future.

  3. Ozone Depletion by Hydrofluorocarbons

    NASA Astrophysics Data System (ADS)

    Hurwitz, M.; Fleming, E. L.; Newman, P. A.; Li, F.; Mlawer, E. J.; Cady-Pereira, K. E.; Bailey, R.

    2015-12-01

    Hydrofluorocarbons (HFCs) are second-generation replacements for the chlorofluorocarbons (CFCs), halons and other substances that caused the 'ozone hole'. Atmospheric concentrations of HFCs are projected to increase dramatically in the coming decades. Coupled chemistry-climate simulations forced by these projections show that HFCs will impact the global atmosphere in 2050. As strong radiative forcers, HFCs modulate atmospheric temperature, thereby changing ozone-destroying catalytic cycles and enhancing the stratospheric circulation. These changes lead to a weak depletion of stratospheric ozone. Sensitivity simulations with the NASA Goddard Space Flight Center (GSFC) 2D model show that HFC-125 is the most important contributor to atmospheric change in 2050, as compared with HFC-23, HFC-32, HFC-134a and HFC-143a. Incorporating the interactions between chemistry, radiation and dynamics, for a likely 2050 climate, ozone depletion potentials (ODPs) for HFCs range from 4.3x10-4 to 3.5x10-2; previously HFCs were assumed to have negligible ODPs since these species lack chlorine or bromine atoms. The ozone impacts of HFCs are further investigated with the Goddard Earth Observing System Chemistry-Climate Model (GEOSCCM). The GEOSCCM is a three-dimensional, fully coupled ocean-atmosphere model with interactive stratospheric chemistry. Sensitivity simulations in which CO2, CFC-11 and HCFC-22 are enhanced individually are used as proxies for the atmospheric response to the HFC concentrations expected by the mid-21st century. Sensitivity simulations provide quantitative estimates of the impacts of these greenhouse gases on global total ozone, and can be used to assess their effects on the recovery of Antarctic ozone.

  4. Palaeogenetic analysis of (pre)historic artifacts and its significance for anthropology.

    PubMed

    Burger, J; Hummel, S; Pfeiffer, I; Herrmann, B

    2000-03-01

    The possibility of isolating ancient DNA (aDNA) from all kinds of (pre)historic anthropogenetic artifacts opens new perspectives. This study applies palaeogenetic techniques to three anthropological issues: 1. Palaeodiet. DNA sequences from organic residues in vessels identify Precolumbian Aztec diet. 2. (Pre)historic husbandry and economic structures. aDNA data can reveal the species and the genetic evolutionary stage of animals and plants and show the manner and the extent of their growth, cultivation, or domestication. 3. Production techniques, use, and functionality. Identification of the plant or animal source of an archaeological find can reveal the use or the function of the find. Examples from a Celtic "sausage-end" and an Aztec "eye salve" are given.

  5. Late Quaternary environments and prehistoric occupation in the lower White Nile valley, central Sudan

    NASA Astrophysics Data System (ADS)

    Williams, Martin A. J.; Usai, Donatella; Salvatori, Sandro; Williams, Frances M.; Zerboni, Andrea; Maritan, Lara; Linseele, Veerle

    2015-12-01

    Despite the major contributions provided over fifty years ago by A.J. Arkell and J.D. Tothill to our understanding of late Quaternary environments and prehistoric occupation near the confluence of the Blue and White Nile in central Sudan, three key questions have remained unresolved since then. (a) Was the decline in Nile flood levels from early Holocene times onwards caused by a reduction in Nile discharge, or by channel incision, or both? (b) Was the regional climate wetter during times of high Nile floods and drier during times of low Nile floods? (c) Given the high degree of disturbance of Mesolithic and later prehistoric sites, is it possible to identify primary-context, stratified and undisturbed occupation? Drawing upon dated evidence from three sites to the east of and three to the west of the lower White Nile, we provide a qualified answer to the first question and documented affirmative answers to the second and third questions.

  6. Neural-tube defects in a prehistoric south-western Indian population.

    PubMed

    Devor, E J; Cordell, L S

    1981-01-01

    Concern with the frequency and patterning of the occurrence of midline neural-tube defects among contemporary human populations is widespread. These defects are, however, quite old and occur in unusually high numbers of prehistoric skeletons. A common explanation offered for such high incidence has been inbreeding among small, reproductively isolated populations. In a sample of 54 skeletons from the prehistoric south-western Indian site of Tijeras Pueblo in New Mexico, failure of neural-tube closure occurs in 10% of sacra recovered. While a more homogeneous genetic background and inbreeding may account for a portion of this elevated prevalence, the cause appears to lie with cultural-environmental factors. It is suggested that the aetiology of these conditions has become more complex in recent human history.

  7. Phytoliths in Pottery Reveal the Use of Spice in European Prehistoric Cuisine

    PubMed Central

    Saul, Hayley; Madella, Marco; Fischer, Anders; Glykou, Aikaterini; Hartz, Sönke; Craig, Oliver E.

    2013-01-01

    Here we present evidence of phytoliths preserved in carbonised food deposits on prehistoric pottery from the western Baltic dating from 6,100 cal BP to 5750 cal BP. Based on comparisons to over 120 European and Asian species, our observations are consistent with phytolith morphologies observed in modern garlic mustard seed (Alliaria petiolata (M. Bieb) Cavara & Grande). As this seed has a strong flavour, little nutritional value, and the phytoliths are found in pots along with terrestrial and marine animal residues, these findings are the first direct evidence for the spicing of food in European prehistoric cuisine. Our evidence suggests a much greater antiquity to the spicing of foods than is evident from the macrofossil record, and challenges the view that plants were exploited by hunter-gatherers and early agriculturalists solely for energy requirements, rather than taste. PMID:23990910

  8. Use of collagenase to purify collagen from prehistoric bones for stable isotopic analysis

    NASA Astrophysics Data System (ADS)

    DeNiro, Michael J.; Weiner, Stephen

    1988-10-01

    The low molecular weight hydrolysis products of the reaction between collagenase and the HCl insoluble organic fraction from modern and well-preserved prehistoric bones have the same stable carbon and nitrogen isotopic compositions and amino acid composition as "collagen" extracted by dissolution in warm dilute acid. The hydrolysis products produced using the collagenase method from some poorly preserved fossil bones have the same amino acid composition as the products produced from modern bones, even though the "collagen" extracted from these bones by the conventional solubility method bears no similarity to modern collagen either in terms of amino acid or isotopic composition. These observations suggest that collagenase can possibly be used to purify a fraction from such poorly preserved prehistoric bones that retains its in vivo isotope ratios, thereby permitting isotopic paleodietary reconstruction for bones that cannot be studied with currently available techniques.

  9. Phytoliths in pottery reveal the use of spice in European prehistoric cuisine.

    PubMed

    Saul, Hayley; Madella, Marco; Fischer, Anders; Glykou, Aikaterini; Hartz, Sönke; Craig, Oliver E

    2013-01-01

    Here we present evidence of phytoliths preserved in carbonised food deposits on prehistoric pottery from the western Baltic dating from 6,100 cal BP to 5750 cal BP. Based on comparisons to over 120 European and Asian species, our observations are consistent with phytolith morphologies observed in modern garlic mustard seed (Alliaria petiolata (M. Bieb) Cavara & Grande). As this seed has a strong flavour, little nutritional value, and the phytoliths are found in pots along with terrestrial and marine animal residues, these findings are the first direct evidence for the spicing of food in European prehistoric cuisine. Our evidence suggests a much greater antiquity to the spicing of foods than is evident from the macrofossil record, and challenges the view that plants were exploited by hunter-gatherers and early agriculturalists solely for energy requirements, rather than taste.

  10. Prehistoric cave painting PIXE analysis for the identification of paint ``pots''

    NASA Astrophysics Data System (ADS)

    Menu, Michel; Walter, Philippe

    1992-02-01

    Prior to the advent of modern analytical techniques, the methods of producing prehistoric paintings were a subject of conjecture. We have sampled and extensively analysed prehistoric paint in several French cave sites of the Upper Paleolithic. The results indicate that, more than 12000 years ago, artists working within a restricted area utilized a number of "paint recipes" which are chronologically significant and may thus assist in dating the paintings. These recipes consist of a precise manufacturing of the different elements: pigment, extender and sometimes binder. The chemical impurities associated with the paint (here the mineral part composed of pigment + extender) may determine the "paint pot". These impurities are characteristic of the sources of the minerals. Among the different sites that we analysed, three from the most important ones are presented here: Niaux, Gargas (French Pyrenees) and Lascaux (Perigord, France).

  11. Gulf of Mexico Integrated Science - Tampa Bay Study - Historical and Prehistorical Record of Tampa Bay Environments

    USGS Publications Warehouse

    Edgar, Terry

    2005-01-01

    To study how Tampa Bay, Florida, has changed over time, the prehistorical conditions and natural variations in the bay environment are being evaluated. These variations can be tracked by examining the sediments that have accumulated in and around the bay. The prehistorical record, which pre-dates settlers' arrival in the Tampa Bay area around 1850, provides a baseline with which to compare and evaluate the magnitude and effects of sea-level, climate, biological, geochemical, and man-made changes. These data also are valuable for planning and conducting projects aimed at restoring wetlands and other estuarine habitats to their original state. In addition, the data provide a basis for judging efforts to improve the health of the bay.

  12. The Lost Worlds of Messmore & Damon: Science, Spectacle & Prehistoric Monsters in early-twentieth century America.

    PubMed

    Manias, Chris

    2016-09-01

    In 1924, the model-making company Messmore & Damon, Inc. of New York unleashed their masterpiece: the Amphibious Dinosaurus Brontosaurus, a moving, breathing, roaring animatronic dinosaur, based on displays in the American Museum of Natural History. Over the 1920s and 1930s, this became the focus of an ever-increasing publicity campaign, as Messmore & Damon exhibited prehistoric automata in department stores, the media, and the Chicago World Fair of 1933-34. These displays were hugely popular and widely discussed, drawing from the increasing public appeal of paleontology. Mixing commercial entertainment with invocations of scientific value, Messmore & Damon's prehistoric creations offer a window into the meaning and popularity of the deep time sciences in early-twentieth century America, and the links between science and spectacle in this period. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Shakeup Ahead for Agricultural Research.

    ERIC Educational Resources Information Center

    Lepkowski, Wil

    1982-01-01

    Reorganization of Agricultural Research Service is under way, triggered by charges that research hasn't kept pace with resource depletion and high cost of farming. A fight is predicted over the 1887 Hatch Act funds ($221 million appropriated by Congress in 1981). Comments on the situation by various individuals are included. (Author/JN)

  14. Sandstone weathering processes damaging prehistoric rock paintings at the Albarracin Cultural Park, NE Spain

    NASA Astrophysics Data System (ADS)

    Benito, G.; Machado, M. J.; Sancho, C.

    1993-09-01

    The rock paintings in cliff-foot caves of the Albarracin Cultural Park are known as some of the most important evidences of the Levantine prehistoric art of Spain (8000 3000 BP). The paintings are on sandstone (Buntsandstein facies) of Triasic age, which may develop intense weathering. The analysis of the variables controlling the weathering indicate that salt and wetting-drying weathering are responsible for granular disintegration and flaking, which lead to rock painting deterioration.

  15. Diet of the prehistoric population of Rapa Nui (Easter Island, Chile) shows environmental adaptation and resilience.

    PubMed

    Jarman, Catrine L; Larsen, Thomas; Hunt, Terry; Lipo, Carl; Solsvik, Reidar; Wallsgrove, Natalie; Ka'apu-Lyons, Cassie; Close, Hilary G; Popp, Brian N

    2017-10-01

    The Rapa Nui "ecocide" narrative questions whether the prehistoric population caused an avoidable ecological disaster through rapid deforestation and over-exploitation of natural resources. The objective of this study was to characterize prehistoric human diets to shed light on human adaptability and land use in an island environment with limited resources. Materials for this study included human, faunal, and botanical remains from the archaeological sites Anakena and Ahu Tepeu on Rapa Nui, dating from c. 1400 AD to the historic period, and modern reference material. We used bulk carbon and nitrogen isotope analyses and amino acid compound specific isotope analyses (AA-CSIA) of collagen isolated from prehistoric human and faunal bone, to assess the use of marine versus terrestrial resources and to investigate the underlying baseline values. Similar isotope analyses of archaeological and modern botanical and marine samples were used to characterize the local environment. Results of carbon and nitrogen AA-CSIA independently show that around half the protein in diets from the humans measured came from marine sources; markedly higher than previous estimates. We also observed higher δ(15) N values in human collagen than could be expected from the local environment. Our results suggest highly elevated δ(15) N values could only have come from consumption of crops grown in substantially manipulated soils. These findings strongly suggest that the prehistoric population adapted and exhibited astute environmental awareness in a harsh environment with nutrient poor soils. Our results also have implications for evaluating marine reservoir corrections of radiocarbon dates. © 2017 Wiley Periodicals, Inc.

  16. Impact of prehistoric cooking practices on paleoenvironmental proxies in shell midden constituents

    NASA Astrophysics Data System (ADS)

    Müller, Peter; Staudigel, Philip; Murray, Sean T.; Westphal, Hildegard; Swart, Peter K.

    2016-04-01

    Paleoenvironmental proxy records such as oxygen isotopes of calcareous skeletal structures like fish otoliths or mollusk shells provide highest-resolution information about environmental conditions experienced by the organism. Accumulations of such skeletal structures by ancient coastal populations in so called "shell midden" deposits provide us with sub-seasonally resolved paleoclimate records covering time spans up to several millennia. Given their high temporal resolution, these deposits are increasingly used for paleoclimate reconstructions and complement our understanding of ancient climate changes. However, gathered as comestibles, most of these skeletal remains were subject to prehistoric cooking methods prior to deposition. The associated alteration of the chemical proxy signatures as well as the subsequent error for paleoenvironmental reconstructions remained almost entirely neglected so far. Here, we present clumped isotope, conventional oxygen and carbon isotopes as well as element:Ca ratios measured in modern bivalve shells after exposing them to different prehistoric cooking methods. Our data show that most cooking methods considerably alter commonly used paleoclimate proxy systems which can lead to substantial misinterpretations of ancient climate conditions. Since the magnitude of chemical alteration is not distinguishable from natural temperature variability in most coastal settings, the alteration of shell midden constituents by prehistoric cooking remains likely unnoticed in most cases. Thus, depending on the cooking method, pre-depositional heating might have introduced considerable errors into previous paleoclimate studies. However, our data also show that clumped isotope thermometry represents a suitable diagnostic tool to detect such pre-depositional cooking events and also allows differentiating between the most commonly applied prehistoric cooking methods.

  17. Prehistoric contacts over the Straits of Gibraltar indicated by genetic analysis of Iberian Bronze Age cattle

    PubMed Central

    Anderung, Cecilia; Bouwman, Abigail; Persson, Per; Carretero, José Miguel; Ortega, Ana Isabel; Elburg, Rengert; Smith, Colin; Arsuaga, Juan Luis; Ellegren, Hans; Götherström, Anders

    2005-01-01

    The geographic situation of the Iberian Peninsula makes it a natural link between Europe and North Africa. However, it is a matter of debate to what extent African influences via the Straits Gibraltar have affected Iberia's prehistoric development. Because early African pastoralist communities were dedicated to cattle breeding, a possible means to detect prehistoric African–Iberian contacts might be to analyze the origin of cattle breeds on the Iberian Peninsula. Some contemporary Iberian cattle breeds show a mtDNA haplotype, T1, that is characteristic to African breeds, generally explained as being the result of the Muslim expansion of the 8th century A.D., and of modern imports. To test a possible earlier African influence, we analyzed mtDNA of Bronze Age cattle from the Portalón cave at the Atapuerca site in northern Spain. Although the majority of samples showed the haplotype T3 that dominates among European breeds of today, the T1 haplotype was found in one specimen radiocarbon dated 1800 calibrated years B.C. Accepting T1 as being of African origin, this result indicates prehistoric African–Iberian contacts and lends support to archaeological finds linking early African and Iberian cultures. We also found a wild ox haplotype in the Iberian Bronze Age sample, reflecting local hybridization or backcrossing or that aurochs were hunted by these farming cultures. PMID:15941827

  18. Prehistoric inter-archipelago trading of Polynesian tree snails leaves a conservation legacy

    PubMed Central

    Lee, Taehwan; Burch, John B; Coote, Trevor; Fontaine, Benoît; Gargominy, Olivier; Pearce-Kelly, Paul; Foighil, Diarmaid Ó

    2007-01-01

    Inter-archipelago exchange networks were an important aspect of prehistoric Polynesian societies. We report here a novel genetic characterization of a prehistoric exchange network involving an endemic Pacific island tree snail, Partula hyalina. It occurs in the Society (Tahiti only), Austral and Southern Cook Islands. Our genetic data, based on museum, captive and wild-caught samples, establish Tahiti as the source island. The source lineage is polymorphic in shell coloration and contains a second nominal species, the dark-shelled Partula clara, in addition to the white-shelled P. hyalina. Prehistoric inter-island introductions were non-random: they involved white-shelled snails only and were exclusively inter-archipelago in scope. Partulid shells were commonly used in regional Polynesian jewellery, and we propose that the white-shelled P. hyalina, originally restricted to Tahiti, had aesthetic value throughout these archipelagoes. Demand within the Society Islands could be best met by trading dead shells, but a low rate of inter-archipelago exchange may have prompted the establishment of multiple founder populations in the Australs and Southern Cooks. The alien carnivorous land snail Euglandina rosea has recently devastated populations of all 61 endemic species of Society Island partulid snails. Southern Cooks and Australs P. hyalina now represent the only unscathed wild populations remaining of this once spectacular land snail radiation. PMID:17848368

  19. Prehistoric inter-archipelago trading of Polynesian tree snails leaves a conservation legacy.

    PubMed

    Lee, Taehwan; Burch, John B; Coote, Trevor; Fontaine, Benoît; Gargominy, Olivier; Pearce-Kelly, Paul; Foighil, Diarmaid O

    2007-11-22

    Inter-archipelago exchange networks were an important aspect of prehistoric Polynesian societies. We report here a novel genetic characterization of a prehistoric exchange network involving an endemic Pacific island tree snail, Partula hyalina. It occurs in the Society (Tahiti only), Austral and Southern Cook Islands. Our genetic data, based on museum, captive and wild-caught samples, establish Tahiti as the source island. The source lineage is polymorphic in shell coloration and contains a second nominal species, the dark-shelled Partula clara, in addition to the white-shelled P. hyalina. Prehistoric inter-island introductions were non-random: they involved white-shelled snails only and were exclusively inter-archipelago in scope. Partulid shells were commonly used in regional Polynesian jewellery, and we propose that the white-shelled P. hyalina, originally restricted to Tahiti, had aesthetic value throughout these archipelagoes. Demand within the Society Islands could be best met by trading dead shells, but a low rate of inter-archipelago exchange may have prompted the establishment of multiple founder populations in the Australs and Southern Cooks. The alien carnivorous land snail Euglandina rosea has recently devastated populations of all 61 endemic species of Society Island partulid snails. Southern Cooks and Australs P. hyalina now represent the only unscathed wild populations remaining of this once spectacular land snail radiation.

  20. Diet and nutrition of prehistoric populations at the alluvial banks of the Parana River.

    PubMed

    Cornero, S; Puche, R C

    2000-01-01

    This study attempts to characterize the health status and diet of prehistoric populations (1,000-2,000 years BP), dwelling at both banks of Parana River, between 29 degrees S and 32 degrees S. The data obtained suggest that these prehistoric populations had an adequate nutritional status, with complete proteins in the diet, as suggested by the ratio strontium/calcium in their bone mineral (0.71 +/- 0.04 microgram Srx1,000/mg Ca). The overall frequency of dental caries (4.9%) coincides with that reported for hunters-gatherers. The average mineral densities of the tibiae of adult subjects exhumed at two sites (males: 1.51 +/- 0.07 gr/cm2; females: 1.24 +/- 0.06 gr/cm2) suggested that they had significant bone mass, an asset compatible with adequate nutrition. In metacarpals, the amount of cortical tissue also suggests bone mass comparable to contemporaneous controls. The growth and development of the prehistoric populations studied are deemed normal as shown by the clear sexual dimorphism of their estimated heights at adult age (males: 177-183 cm; females 152-166 cm) and their bone mass.

  1. Evidence for large prehistoric earthquakes in the northern New Madrid Seismic Zone, central United States

    USGS Publications Warehouse

    Li, Y.; Schweig, E.S.; Tuttle, M.P.; Ellis, M.A.

    1998-01-01

    We surveyed the area north of New Madris, Missouri, for prehistoric liquefaction deposits and uncovered two new sites with evidence of pre-1811 earthquakes. At one site, located about 20 km northeast of New Madrid, Missouri, radiocarbon dating indicates that an upper sand blow was probably deposited after A.D. 1510 and a lower sand blow was deposited prior to A.D. 1040. A sand blow at another site about 45 km northeast of New Madrid, Missouri, is dated as likely being deposited between A.D.55 and A.D. 1620 and represents the northernmost recognized expression of prehistoric liquefaction likely related to the New Madrid seismic zone. This study, taken together with other data, supports the occurrence of at least two earthquakes strong enough to indcue liquefaction or faulting before A.D. 1811, and after A.D. 400. One earthquake probably occurred around AD 900 and a second earthquake occurred around A.D. 1350. The data are not yet sufficient to estimate the magnitudes of the causative earthquakes for these liquefaction deposits although we conclude that all of the earthquakes are at least moment magnitude M ~6.8, the size of the 1895 Charleston, Missouri, earthquake. A more rigorous estimate of the number and sizes of prehistoric earthquakes in the New Madrid sesmic zone awaits evaluation of additional sites.

  2. Y Chromosome analysis of prehistoric human populations in the West Liao River Valley, Northeast China

    PubMed Central

    2013-01-01

    Background The West Liao River valley in Northeast China is an ecologically diverse region, populated in prehistory by human populations with a wide range of cultures and modes of subsistence. To help understand the human evolutionary history of this region, we performed Y chromosome analyses on ancient human remains from archaeological sites ranging in age from 6500 to 2700 BP. Results 47 of the 70 individuals provided reproducible results. They were assigned into five different Y sub-haplogroups using diagnostic single nucleotide polymorphisms, namely N1 (xN1a, N1c), N1c, C/C3e, O3a (O3a3) and O3a3c. We also used 17 Y short tandem repeat loci in the non-recombining portion of the Y chromosome. There appears to be significant genetic differences between populations of the West Liao River valley and adjacent cultural complexes in the prehistoric period, and these prehistoric populations were shown to carry similar haplotypes as present-day Northeast Asians, but at markedly different frequencies. Conclusion Our results suggest that the prehistoric cultural transitions were associated with immigration from the Yellow River valley and the northern steppe into the West Liao River valley. They reveal the temporal continuity of Y chromosome lineages in populations of the West Liao River valley over 5000 years, with a concurrent increase in lineage diversity caused by an influx of immigrants from other populations. PMID:24079706

  3. Mollusk collecting and environmental change during the Prehistoric Period in the Mariana Islands

    NASA Astrophysics Data System (ADS)

    Amesbury, J. R.

    2007-12-01

    Archaeological research in the Mariana Islands has revealed changes in mollusk collecting during the Prehistoric Period (approximately 1500 BC to AD 1521). The earliest people at Tumon Bay, Guam and Chalan Piao, Saipan collected mostly bivalves, especially the arc clam Anadara antiquata. After several hundred years, they no longer collected A. antiquata, but collected smaller bivalves instead. By AD 1000, they collected mostly gastropods, primarily the coral reef species Strombus gibberulus gibbosus. One possible explanation is that the people preferred the large arc clam but overharvested it until they were forced to eat the smaller bivalves and then the snails. However, recent evidence in the form of mangrove wood and mangrove pollen supports another explanation, one of non-anthropogenic environmental change. In this case, the relative sea-level decline, which took place in the Marianas within the last 4,000 years, caused the demise of mangrove habitats and of the arc clam at Tumon Bay, Guam and Chalan Piao, Saipan. As mangrove habitats were diminished by sea-level decline, collecting effort shifted to coral reefs, and S. gibberulus gibbosus was harvested throughout the remainder of the Prehistoric Period and into the Historic Period. Southern Guam is the only area in the Marianas in which A. antiquata increased in abundance during the Prehistoric Period. The same types of evidence, mangrove wood and mangrove pollen, indicate that, in contrast to the situation at Tumon Bay and Chalan Piao, mangroves increased in abundance in southern Guam.

  4. Patterns of prehistoric human mobility in Polynesia indicated by mtDNA from the Pacific rat

    PubMed Central

    Matisoo-Smith, E.; Roberts, R. M.; Irwin, G. J.; Allen, J. S.; Penny, D.; Lambert, D. M.

    1998-01-01

    Human settlement of Polynesia was a major event in world prehistory. Despite the vastness of the distances covered, research suggests that prehistoric Polynesian populations maintained spheres of continuing interaction for at least some period of time in some regions. A low level of genetic variation in ancestral Polynesian populations, genetic admixture (both prehistoric and post-European contact), and severe population crashes resulting from introduction of European diseases make it difficult to trace prehistoric human mobility in the region by using only human genetic and morphological markers. We focus instead on an animal that accompanied the ancestral Polynesians on their voyages. DNA phylogenies derived from mitochondrial control-region sequences of Pacific rats (Rattus exulans) from east Polynesia are presented. A range of specific hypotheses regarding the degree of interaction within Polynesia are tested. These include the issues of multiple contacts between central east Polynesia and the geographically distinct archipelagos of New Zealand and Hawaii. Results are inconsistent with models of Pacific settlement involving substantial isolation after colonization and confirm the value of genetic studies on commensal species for elucidating the history of human settlement. PMID:9844030

  5. 12. VIEW OF DEPLETED URANIUM INGOT AND MOLDS. DEPLETED URANIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW OF DEPLETED URANIUM INGOT AND MOLDS. DEPLETED URANIUM CASTING OPERATIONS CEASED IN 1988. (11/14/57) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  6. African Universities Tackle the Continent's Agricultural Crisis

    ERIC Educational Resources Information Center

    Lindow, Megan

    2009-01-01

    Pests, population growth, and depleted soil have wreaked havoc on agriculture in Africa, so universities across the continent are rethinking how they teach the topic. Some African universities have been building their own networks and pooling their limited resources to train more agricultural scientists and improve their responsiveness to the…

  7. African Universities Tackle the Continent's Agricultural Crisis

    ERIC Educational Resources Information Center

    Lindow, Megan

    2009-01-01

    Pests, population growth, and depleted soil have wreaked havoc on agriculture in Africa, so universities across the continent are rethinking how they teach the topic. Some African universities have been building their own networks and pooling their limited resources to train more agricultural scientists and improve their responsiveness to the…

  8. Long-term groundwater depletion in the United States

    USGS Publications Warehouse

    Konikow, Leonard F.

    2015-01-01

    The volume of groundwater stored in the subsurface in the United States decreased by almost 1000 km3 during 1900–2008. The aquifer systems with the three largest volumes of storage depletion include the High Plains aquifer, the Mississippi Embayment section of the Gulf Coastal Plain aquifer system, and the Central Valley of California. Depletion rates accelerated during 1945–1960, averaging 13.6 km3/year during the last half of the century, and after 2000 increased again to about 24 km3/year. Depletion intensity is a new parameter, introduced here, to provide a more consistent basis for comparing storage depletion problems among various aquifers by factoring in time and areal extent of the aquifer. During 2001–2008, the Central Valley of California had the largest depletion intensity. Groundwater depletion in the United States can explain 1.4% of observed sea-level rise during the 108-year study period and 2.1% during 2001–2008. Groundwater depletion must be confronted on local and regional scales to help reduce demand (primarily in irrigated agriculture) and/or increase supply.

  9. Long-term groundwater depletion in the United States.

    PubMed

    Konikow, Leonard F

    2015-01-01

    The volume of groundwater stored in the subsurface in the United States decreased by almost 1000 km3 during 1900-2008. The aquifer systems with the three largest volumes of storage depletion include the High Plains aquifer, the Mississippi Embayment section of the Gulf Coastal Plain aquifer system, and the Central Valley of California. Depletion rates accelerated during 1945-1960, averaging 13.6 km3/year during the last half of the century, and after 2000 increased again to about 24 km3/year. Depletion intensity is a new parameter, introduced here, to provide a more consistent basis for comparing storage depletion problems among various aquifers by factoring in time and areal extent of the aquifer. During 2001-2008, the Central Valley of California had the largest depletion intensity. Groundwater depletion in the United States can explain 1.4% of observed sea-level rise during the 108-year study period and 2.1% during 2001-2008. Groundwater depletion must be confronted on local and regional scales to help reduce demand (primarily in irrigated agriculture) and/or increase supply.

  10. Depleted Uranium in Repositories

    SciTech Connect

    Haire, M.J.; Croff, A.G.

    1997-12-31

    For uranium to be useful in most fission nuclear reactors, it must be enriched (i.e. the concentration of the fissile isotope 235U must be increased). Therefore, depleted uranium (DU)-uranium which has less than naturally occurring concentrations of 235U-is a co-product of the enrichment process. Four to six tons of DU exist for every ton of fresh light water reactor fuel. There were 407,006 MgU 407,000 metric tons (t) of DU stored on U.S. Department of Energy (DOE) sites as of July 1993. If this DU were to be declared surplus, converted to a stable oxide form, and emplaced in a near surface disposal facility, the costs are estimated to be several billion dollars. However, the U.S. Nuclear Regulatory Commission has stated that near surface disposal of large quantities of DU tails is not appropriate. Thus, there is the possibility that disposition via disposal will be in a deep geological repository. One alternative that may significantly reduce the cost of DU disposition is to use it beneficially. In fact, DOE has begun the Beneficial Uses of DU Project to identify large scale uses of DU and to encourage its reuse. Several beneficial uses, many of which involve applications in the repository per se or in managing the wastes to go into the repository, are discussed in this report.

  11. Pre-Hispanic agricultural decline prior to the Spanish Conquest in southern Central America

    NASA Astrophysics Data System (ADS)

    Taylor, Zachary P.; Horn, Sally P.; Finkelstein, David B.

    2013-08-01

    Archeological and paleoenvironmental records from southern Central America attribute population collapse to the Spanish Conquest about 500 years ago. Paleoclimate records from the circum-Caribbean have shown evidence of severe, regional droughts that contributed to the collapse of the Mayan Civilization, but there are few records of these droughts in southern Central America and no records of their effects on prehistoric populations in the region. Here we present a high-resolution lake sediment record of prehistoric agricultural activities using bulk sediment stable carbon isotopes from Laguna Zoncho, Costa Rica. We find isotopic evidence that agriculture was nearly absent from the watershed approximately 220 years prior to the Spanish arrival in Costa Rica and identify two distinct periods of agricultural decline, 1150-970 and 860-640 cal yr BP, which correspond to severe droughts in central Mexico. We attribute decreases in agriculture to a weakened Central American monsoon, which would have shortened the growing season at Laguna Zoncho, reduced crop yields, and negatively affected prehistoric populations.

  12. The Toxicity of Depleted Uranium

    PubMed Central

    Briner, Wayne

    2010-01-01

    Depleted uranium (DU) is an emerging environmental pollutant that is introduced into the environment primarily by military activity. While depleted uranium is less radioactive than natural uranium, it still retains all the chemical toxicity associated with the original element. In large doses the kidney is the target organ for the acute chemical toxicity of this metal, producing potentially lethal tubular necrosis. In contrast, chronic low dose exposure to depleted uranium may not produce a clear and defined set of symptoms. Chronic low-dose, or subacute, exposure to depleted uranium alters the appearance of milestones in developing organisms. Adult animals that were exposed to depleted uranium during development display persistent alterations in behavior, even after cessation of depleted uranium exposure. Adult animals exposed to depleted uranium demonstrate altered behaviors and a variety of alterations to brain chemistry. Despite its reduced level of radioactivity evidence continues to accumulate that depleted uranium, if ingested, may pose a radiologic hazard. The current state of knowledge concerning DU is discussed. PMID:20195447

  13. Ego depletion impairs implicit learning.

    PubMed

    Thompson, Kelsey R; Sanchez, Daniel J; Wesley, Abigail H; Reber, Paul J

    2014-01-01

    Implicit skill learning occurs incidentally and without conscious awareness of what is learned. However, the rate and effectiveness of learning may still be affected by decreased availability of central processing resources. Dual-task experiments have generally found impairments in implicit learning, however, these studies have also shown that certain characteristics of the secondary task (e.g., timing) can complicate the interpretation of these results. To avoid this problem, the current experiments used a novel method to impose resource constraints prior to engaging in skill learning. Ego depletion theory states that humans possess a limited store of cognitive resources that, when depleted, results in deficits in self-regulation and cognitive control. In a first experiment, we used a standard ego depletion manipulation prior to performance of the Serial Interception Sequence Learning (SISL) task. Depleted participants exhibited poorer test performance than did non-depleted controls, indicating that reducing available executive resources may adversely affect implicit sequence learning, expression of sequence knowledge, or both. In a second experiment, depletion was administered either prior to or after training. Participants who reported higher levels of depletion before or after training again showed less sequence-specific knowledge on the post-training assessment. However, the results did not allow for clear separation of ego depletion effects on learning versus subsequent sequence-specific performance. These results indicate that performance on an implicitly learned sequence can be impaired by a reduction in executive resources, in spite of learning taking place outside of awareness and without conscious intent.

  14. Agriculture: Newsroom

    EPA Pesticide Factsheets

    Agriculture Newsroom. News releases, reports, and other documents from around EPA that are of interest or direct importance to the environmental management or compliance efforts of the agricultural community.

  15. Grassland agriculture

    USDA-ARS?s Scientific Manuscript database

    Agriculture in grassland environments is facing multiple stresses from: shifting demographics, declining and fragmented agricultural landscapes, declining environmental quality, variable and changing climate, volatile and increasing energy costs, marginal economic returns, and globalization. Degrad...

  16. Stratospheric ozone depletion.

    PubMed

    Rowland, F Sherwood

    2006-05-29

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290-320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime-the 'Antarctic ozone hole'. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules.

  17. Stratospheric ozone depletion

    PubMed Central

    Rowland, F. Sherwood

    2006-01-01

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290–320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime—the ‘Antarctic ozone hole’. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules. PMID:16627294

  18. A worldwide view of groundwater depletion

    NASA Astrophysics Data System (ADS)

    van Beek, L. P.; Wada, Y.; van Kempen, C.; Reckman, J. W.; Vasak, S.; Bierkens, M. F.

    2010-12-01

    During the last decades, global water demand has increased two-fold due to increasing population, expanding irrigated area and economic development. Globally such demand can be met by surface water availability (i.e., water in rivers, lakes and reservoirs) but regional variations are large and the absence of sufficient rainfall and run-off increasingly encourages the use of groundwater resources, particularly in the (semi-)arid regions of the world. Excessive abstraction for irrigation frequently leads to overexploitation, i.e. if groundwater abstraction exceeds the natural groundwater recharge over extensive areas and prolonged times, persistent groundwater depletion may occur. Observations and various regional studies have revealed that groundwater depletion is a substantial issue in regions such as Northwest India, Northeast Pakistan, Central USA, Northeast China and Iran. Here we provide a global overview of groundwater depletion from the year 1960 to 2000 at a spatial resolution of 0.5 degree by assessing groundwater recharge with the global hydrological model PCR-GLOBWB and subtracting estimates of groundwater abstraction obtained from IGRAC-GGIS database. PCR-GLOBWB was forced by the CRU climate dataset downscaled to daily time steps using ERA40 re-analysis data. PCR-GLOBWB simulates daily global groundwater recharge (0.5 degree) while considering sub-grid variability of each grid cell (e.g., short and tall vegetation, different soil types, fraction of saturated soil). Country statistics of groundwater abstraction were downscaled to 0.5 degree by using water demand (i.e., agriculture, industry and domestic) as a proxy. To limit problems related to increased capture of discharge and increased recharge due to groundwater pumping, we restricted our analysis to sub-humid to arid areas. The uncertainty in the resulting estimates was assessed by a Monte Carlo analysis of 100 realizations of groundwater recharge and 100 realizations of groundwater abstraction

  19. Testing fully depleted CCD

    NASA Astrophysics Data System (ADS)

    Casas, Ricard; Cardiel-Sas, Laia; Castander, Francisco J.; Jiménez, Jorge; de Vicente, Juan

    2014-08-01

    The focal plane of the PAU camera is composed of eighteen 2K x 4K CCDs. These devices, plus four spares, were provided by the Japanese company Hamamatsu Photonics K.K. with type no. S10892-04(X). These detectors are 200 μm thick fully depleted and back illuminated with an n-type silicon base. They have been built with a specific coating to be sensitive in the range from 300 to 1,100 nm. Their square pixel size is 15 μm. The read-out system consists of a Monsoon controller (NOAO) and the panVIEW software package. The deafualt CCD read-out speed is 133 kpixel/s. This is the value used in the calibration process. Before installing these devices in the camera focal plane, they were characterized using the facilities of the ICE (CSIC- IEEC) and IFAE in the UAB Campus in Bellaterra (Barcelona, Catalonia, Spain). The basic tests performed for all CCDs were to obtain the photon transfer curve (PTC), the charge transfer efficiency (CTE) using X-rays and the EPER method, linearity, read-out noise, dark current, persistence, cosmetics and quantum efficiency. The X-rays images were also used for the analysis of the charge diffusion for different substrate voltages (VSUB). Regarding the cosmetics, and in addition to white and dark pixels, some patterns were also found. The first one, which appears in all devices, is the presence of half circles in the external edges. The origin of this pattern can be related to the assembly process. A second one appears in the dark images, and shows bright arcs connecting corners along the vertical axis of the CCD. This feature appears in all CCDs exactly in the same position so our guess is that the pattern is due to electrical fields. Finally, and just in two devices, there is a spot with wavelength dependence whose origin could be the result of a defectous coating process.

  20. Agricultural Waste.

    PubMed

    Xue, Ling; Zhang, Panpan; Shu, Huajie; Chang, Chein-Chi; Wang, Renqing; Zhang, Shuping

    2016-10-01

    In recent years, the quantity of agricultural waste has been rising rapidly all over the world. As a result, the environmental problems and negative impacts of agricultural waste are drawn more and more attention. Therefore, there is a need to adopt proper approaches to reduce and reuse agricultural waste. This review presented about 200 literatures published in 2015 relating to the topic of agricultural waste. The review examined research on agricultural waste in 2015 from the following four aspects: the characterization, reuse, treatment, and management. Researchers highlighted the importance to reuse agricultural waste and investigated the potential to utilize it as biofertilizers, cultivation material, soil amendments, adsorbent, material, energy recycling, enzyme and catalyst etc. The treatment of agricultural waste included carbonization, biodegradation, composting hydrolysis and pyrolysis. Moreover, this review analyzed the differences of the research progress in 2015 from 2014. It may help to reveal the new findings and new trends in this field in 2015 comparing to 2014.

  1. Transequatorial Propagation and Depletion Precursors

    NASA Astrophysics Data System (ADS)

    Miller, E. S.; Bust, G. S.; Kaeppler, S. R.; Frissell, N. A.; Paxton, L. J.

    2014-12-01

    The bottomside equatorial ionosphere in the afternoon and evening sector frequently evolves rapidly from smoothly stratified to violently unstable with large wedges of depleted plasma growing through to the topside on timescales of a few tens of minutes. These depletions have numerous practical impacts on radio propagation, including amplitude scintillation, field-aligned irregularity scatter, HF blackouts, and long-distance transequatorial propagation at frequencies above the MUF. Practical impacts notwithstanding, the pathways and conditions under which depletions form remain a topic of vigorous inquiry some 80 years after their first report. Structuring of the pre-sunset ionosphere---morphology of the equatorial anomalies and long-wavelength undulations of the isodensity contours on the bottomside---are likely to hold some clues to conditions that are conducive to depletion formation. The Conjugate Depletion Experiment is an upcoming transequatorial forward-scatter HF/VHF experiment to investigate pre-sunset undulations and their connection with depletion formation. We will present initial results from the Conjugate Depletion Experiment, as well as a companion analysis of a massive HF propagation data set.

  2. Vocational Agriculture Education. Agricultural Mechanics.

    ERIC Educational Resources Information Center

    Smith, Eddie; And Others

    To assist teachers in agricultural mechanics in providing comprehensive instruction to their students, this curriculum guide treats both the mechanical skills and knowlege necessary for this specialized area. Six sections are included, as follow: orientation and safety; agricultural mechanics skills; agricultural power and machinery; agricultural…

  3. Human Migration Patterns in Yemen and Implications for Reconstructing Prehistoric Population Movements

    PubMed Central

    Miró-Herrans, Aida T.; Al-Meeri, Ali; Mulligan, Connie J.

    2014-01-01

    Population migration has played an important role in human evolutionary history and in the patterning of human genetic variation. A deeper and empirically-based understanding of human migration dynamics is needed in order to interpret genetic and archaeological evidence and to accurately reconstruct the prehistoric processes that comprise human evolutionary history. Current empirical estimates of migration include either short time frames (i.e. within one generation) or partial knowledge about migration, such as proportion of migrants or distance of migration. An analysis of migration that includes both proportion of migrants and distance, and direction over multiple generations would better inform prehistoric reconstructions. To evaluate human migration, we use GPS coordinates from the place of residence of the Yemeni individuals sampled in our study, their birthplaces and their parents' and grandparents' birthplaces to calculate the proportion of migrants, as well as the distance and direction of migration events between each generation. We test for differences in these values between the generations and identify factors that influence the probability of migration. Our results show that the proportion and distance of migration between females and males is similar within generations. In contrast, the proportion and distance of migration is significantly lower in the grandparents' generation, most likely reflecting the decreasing effect of technology. Based on our results, we calculate the proportion of migration events (0.102) and mean and median distances of migration (96 km and 26 km) for the grandparent's generation to represent early times in human evolution. These estimates can serve to set parameter values of demographic models in model-based methods of prehistoric reconstruction, such as approximate Bayesian computation. Our study provides the first empirically-based estimates of human migration over multiple generations in a developing country and these

  4. Human migration patterns in Yemen and implications for reconstructing prehistoric population movements.

    PubMed

    Miró-Herrans, Aida T; Al-Meeri, Ali; Mulligan, Connie J

    2014-01-01

    Population migration has played an important role in human evolutionary history and in the patterning of human genetic variation. A deeper and empirically-based understanding of human migration dynamics is needed in order to interpret genetic and archaeological evidence and to accurately reconstruct the prehistoric processes that comprise human evolutionary history. Current empirical estimates of migration include either short time frames (i.e. within one generation) or partial knowledge about migration, such as proportion of migrants or distance of migration. An analysis of migration that includes both proportion of migrants and distance, and direction over multiple generations would better inform prehistoric reconstructions. To evaluate human migration, we use GPS coordinates from the place of residence of the Yemeni individuals sampled in our study, their birthplaces and their parents' and grandparents' birthplaces to calculate the proportion of migrants, as well as the distance and direction of migration events between each generation. We test for differences in these values between the generations and identify factors that influence the probability of migration. Our results show that the proportion and distance of migration between females and males is similar within generations. In contrast, the proportion and distance of migration is significantly lower in the grandparents' generation, most likely reflecting the decreasing effect of technology. Based on our results, we calculate the proportion of migration events (0.102) and mean and median distances of migration (96 km and 26 km) for the grandparent's generation to represent early times in human evolution. These estimates can serve to set parameter values of demographic models in model-based methods of prehistoric reconstruction, such as approximate Bayesian computation. Our study provides the first empirically-based estimates of human migration over multiple generations in a developing country and these

  5. Argentinean prehistoric pigments' study by combined SEM/EDX and molecular spectroscopy.

    PubMed

    Darchuk, L; Tsybrii, Z; Worobiec, A; Vázquez, C; Palacios, O M; Stefaniak, E A; Gatto Rotondo, G; Sizov, F; Van Grieken, R

    2010-05-01

    Composition of the prehistoric pigments' (from Carriqueo rock shelter, Rio Negro province, Argentina) has been analysed by means of molecular spectroscopy (Fourier transform infrared (FTIR) and micro-Raman) and scanning electron microscopy (SEM) coupled to an energy-dispersive X-ray spectrometer (EDS). Red and yellow pigments were recognized as red and yellow ochre. The matrix of the pigments is composed of one or more substances. According to the matrix composition yellow and red pigments were also divided into two groups-i.e. those containing kaolinite or sulphates. Green pigment was detected as green earth, made up of celadonite as a chromophore.

  6. Craniometric variation and homogeneity in prehistoric/protohistoric Rapa Nui (Easter Island) regional populations.

    PubMed

    Stefan, V H

    1999-12-01

    Discrete cranial morphological traits of prehistoric/protohistoric Rapa Nui (Easter Island) inhabitants have been examined and have illustrated distinct regional or tribal differences; however, craniometric traits have not been as extensively evaluated to determine if similar regional population differences exist. This study examines the range of variability of Rapa Nui craniometrics and utilizes population genetic techniques to evaluate the level of homogeneity/heterogeneity within the island populations. The data consist of 50 cranio-facial measurements of Rapanui (Easter Islanders) skeletal material from the Late Prehistoric (1680-1722) and Protohistoric (1722-1868) periods. The sample was divided into five tribal regions: North, Northeast, South, Southwest, and West. General linear models (GLM) statistical analyses revealed one variable significant for males and 10 for females across tribal regions, totaling 11 regionally significant variables. Discriminant function analyses utilizing crossvalidation provided classification error rates of 55.8% males and 59.0% for females when utilizing those eleven significant variables. Minimum F(ST) values for males (0.06378) and females (0.09409) were calculated from unbiased Mahalanobis D(2) values. These values indicate that males have greater between-group homogeneity than females. The determinant ratio for the Northeast tribal region was the only significant ratio, yet all but one of the regional determinant ratios displayed a pattern of greater male than female mobility. These results indicate that significant craniometric differences between the tribal regions did not exist in prehistoric/protohistoric Rapa Nui populations, supporting the findings of previous research which has documented the homogeneity of the craniometrics of those tribal populations. The calculated minimum F(ST) values indicate the existence of different levels of heterogeneity between the male and female Rapa Nui regional populations resulting

  7. Shrinking fish: comparisons of prehistoric and contemporary salmonids indicate decreasing size at age across millennia.

    PubMed

    Turrero, Pablo; García-Vázquez, Eva; de Leaniz, Carlos Garcia

    2014-10-01

    A comparison of Upper Palaeolithic and contemporary salmonid vertebrae from the Iberian Peninsula indicates that there has been a significant decrease in the mean body size for a given age among Atlantic salmon and brown trout inhabiting the southernmost range of their endemic distribution. Mean size at age was greater in prehistoric specimens for all age classes during the freshwater phase of their life histories. Fisheries-induced evolution (selection for smaller sizes) is an obvious explanation for the observed reduction in fish body size, but recent changes in the aquatic habitat affecting density-dependent growth cannot be ruled out.

  8. Shrinking fish: comparisons of prehistoric and contemporary salmonids indicate decreasing size at age across millennia

    PubMed Central

    Turrero, Pablo; García-Vázquez, Eva; de Leaniz, Carlos Garcia

    2014-01-01

    A comparison of Upper Palaeolithic and contemporary salmonid vertebrae from the Iberian Peninsula indicates that there has been a significant decrease in the mean body size for a given age among Atlantic salmon and brown trout inhabiting the southernmost range of their endemic distribution. Mean size at age was greater in prehistoric specimens for all age classes during the freshwater phase of their life histories. Fisheries-induced evolution (selection for smaller sizes) is an obvious explanation for the observed reduction in fish body size, but recent changes in the aquatic habitat affecting density-dependent growth cannot be ruled out. PMID:26064529

  9. Retention of lead and cadmium in prehistoric and modern human teeth

    SciTech Connect

    Grandjean, P.; Jorgensen, P.J. )

    1990-10-01

    In 5,000-year-old premolars from Nubia and in 500-year-old teeth from Greenland, the lead concentrations were very low; modern teeth contained 10-100 times more lead. In contrast, cadmium concentrations varied by 30-fold in the two prehistorical populations; modern-day cadmium levels were in the lower range of this interval. These data suggest that, when compared to preindustrial exposures, the impact of current environmental lead pollution is considerable, while that of cadmium pollution is much less.

  10. Tree ring correlation between prehistoric landslides and abrupt tectonic events in Seattle, washington.

    PubMed

    Jacoby, G C; Williams, P L; Buckley, B M

    1992-12-04

    Radiocarbon ages of submerged trees on landslide deposits in Lake Washington, Seattle, indicate that the most recent slides in three separate areas may have occurred simultaneously about 1000 years ago. Tree ring crossdating shows that seven bark-bearing trees from one of these recent slides and a tree 23 kilometers to the northwest in a probable tsunami deposit on the shore of Puget Sound died in the same season of the same year. The close coincidence among the most recent lake landslides, a probable tsunami, abrupt subsidence, and other possible seismic events gives evidence for a strong prehistoric earthquake in the Seattle region.

  11. Ego Depletion Impairs Implicit Learning

    PubMed Central

    Thompson, Kelsey R.; Sanchez, Daniel J.; Wesley, Abigail H.; Reber, Paul J.

    2014-01-01

    Implicit skill learning occurs incidentally and without conscious awareness of what is learned. However, the rate and effectiveness of learning may still be affected by decreased availability of central processing resources. Dual-task experiments have generally found impairments in implicit learning, however, these studies have also shown that certain characteristics of the secondary task (e.g., timing) can complicate the interpretation of these results. To avoid this problem, the current experiments used a novel method to impose resource constraints prior to engaging in skill learning. Ego depletion theory states that humans possess a limited store of cognitive resources that, when depleted, results in deficits in self-regulation and cognitive control. In a first experiment, we used a standard ego depletion manipulation prior to performance of the Serial Interception Sequence Learning (SISL) task. Depleted participants exhibited poorer test performance than did non-depleted controls, indicating that reducing available executive resources may adversely affect implicit sequence learning, expression of sequence knowledge, or both. In a second experiment, depletion was administered either prior to or after training. Participants who reported higher levels of depletion before or after training again showed less sequence-specific knowledge on the post-training assessment. However, the results did not allow for clear separation of ego depletion effects on learning versus subsequent sequence-specific performance. These results indicate that performance on an implicitly learned sequence can be impaired by a reduction in executive resources, in spite of learning taking place outside of awareness and without conscious intent. PMID:25275517

  12. Agricultural ecosystems

    SciTech Connect

    Kindscher, K.

    1984-01-01

    The agricultural ecosystem concept promotes a distinctive set of ecological principles that give diversity and stability to the food production process. This system allows people to work more closely with nature and to feel a spiritual connection with the earth. Agricultural ecosystems can be designed to provide numerous advantages. They can be energy conserving, more permanent, make better use of space, reduce and eliminate the need for pesticides, tillage, and chemical fertilizers, and provide food for the local community. The agricultural ecosystem model presented is most suitable for a small-scale farmer or market gardener, but the principles can also be applied on a larger or smaller acreage. The agricultural ecosystem concept is a model-building process that will go through successional stages to a more mature food-producing plant community. The agricultural ecosystem concept expresses permanence and ecology, and is a step toward sustainable agriculture. 55 references, 4 figures.

  13. Policies on global warming and ozone depletion

    SciTech Connect

    Green, B.

    1987-04-01

    The recent discovery of a dramatic seasonal drop in the amount of ozone over Antarctica has catalyzed concern for protection of stratospheric ozone, the layer of gas that shields the entire planet from excess ultraviolet radiation. Conservative scientific models predict about a 5% reduction in the amount of global ozone by the middle of the next century, with large local variations. The predicted global warming from increased emissions of greenhouse gases will also have differing effects on local climate and weather conditions and consequently on agriculture. Although numerous uncertainties are associated with both ozone depletion and a global warming, there is a consensus that world leaders need to address the problems. The US Congress is now beginning to take note of the task. In this article, one representative outlines some perceptions of the problems and the policy options available to Congress.

  14. "When the going gets tough, who keeps going?" Depletion sensitivity moderates the ego-depletion effect.

    PubMed

    Salmon, Stefanie J; Adriaanse, Marieke A; De Vet, Emely; Fennis, Bob M; De Ridder, Denise T D

    2014-01-01

    Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In three studies, we assessed individual differences in depletion sensitivity, and demonstrate that depletion sensitivity moderates ego-depletion effects. The Depletion Sensitivity Scale (DSS) was employed to assess depletion sensitivity. Study 1 employs the DSS to demonstrate that individual differences in sensitivity to ego-depletion exist. Study 2 shows moderate correlations of depletion sensitivity with related self-control concepts, indicating that these scales measure conceptually distinct constructs. Study 3 demonstrates that depletion sensitivity moderates the ego-depletion effect. Specifically, participants who are sensitive to depletion performed worse on a second self-control task, indicating a stronger ego-depletion effect, compared to participants less sensitive to depletion.

  15. Agriculture, summary

    NASA Technical Reports Server (NTRS)

    Baldwin, R.

    1975-01-01

    Applications of remotely sensed data in agriculture are enumerated. These include: predictions of forage for range animal consumption, forest management, soil mapping, and crop inventory and management.

  16. Correlations between radiometric analysis of Quaternary deposits and the chronology of prehistoric settlements from the southeastern Brazilian coast.

    PubMed

    Anjos, R M; Macario, K D; Lima, T A; Veiga, R; Carvalho, C; Fernandes, P J F; Vezzone, M; Bastos, J

    2010-01-01

    Natural gamma radiation measurements of sand deposits were carried out in order to study the chronology of prehistoric colonization of the Brazilian coast during the Holocene. The method employs thorium, uranium and potassium as tracers of the geological provenance of Quaternary deposits, where artificial shellmounds are found. The so-called sambaquis are archaeological settlements, characteristic of fisher-gatherers, specialized in the exploitation of shellfish. Our results show a considerable positive correlation between the formation of coastal deposits, based on cross plots of eTh/eU and eTh/K, and the antiquity of its prehistoric human occupation.

  17. Depleting depletion: Polymer swelling in poor solvent mixtures

    NASA Astrophysics Data System (ADS)

    Mukherji, Debashish; Marques, Carlos; Stuehn, Torsten; Kremer, Kurt

    A polymer collapses in a solvent when the solvent particles dislike monomers more than the repulsion between monomers. This leads to an effective attraction between monomers, also referred to as depletion induced attraction. This attraction is the key factor behind standard polymer collapse in poor solvents. Strikingly, even if a polymer exhibits poor solvent condition in two different solvents, it can also swell in mixtures of these two poor solvents. This collapse-swelling-collapse scenario is displayed by poly(methyl methacrylate) (PMMA) in aqueous alcohol. Using molecular dynamics simulations of a thermodynamically consistent generic model and theoretical arguments, we unveil the microscopic origin of this phenomenon. Our analysis suggests that a subtle interplay of the bulk solution properties and the local depletion forces reduces depletion effects, thus dictating polymer swelling in poor solvent mixtures.

  18. Agricultural Wastes.

    ERIC Educational Resources Information Center

    Jewell, W. J.; Switzenbaum, M. S.

    1978-01-01

    Presents a literature review of agricultural wastes, covering publications of 1976-77. Some of the areas covered are: (1) water characteristics and impacts; (2) waste treatment; (3) reuse of agricultural wastes; and (4) nonpoint pollution sources. A list of 150 references is also presented. (HM)

  19. Agricultural Wastes.

    ERIC Educational Resources Information Center

    Jewell, W. J.; Switzenbaum, M. S.

    1978-01-01

    Presents a literature review of agricultural wastes, covering publications of 1976-77. Some of the areas covered are: (1) water characteristics and impacts; (2) waste treatment; (3) reuse of agricultural wastes; and (4) nonpoint pollution sources. A list of 150 references is also presented. (HM)

  20. VOCATIONAL AGRICULTURE.

    ERIC Educational Resources Information Center

    California State Dept. of Education, Sacramento. Research Coordinating Unit.

    TO ASSIST THOSE WHO MAKE DECISIONS RELATING TO EDUCATIONAL PROGRAMS IN AGRICULTURE, RECENT RESEARCH IN VOCATIONAL AGRICULTURE IS SUMMARIZED. A 1963 STUDY TREATS THE RELATIONSHIP BETWEEN WORK EXPERIENCE AND STUDENT CHARACTERISTICS, PLANS, AND ASPIRATIONS. STUDIES ON POST-SECONDARY EDUCATION CONCERN GUIDELINES FOR TECHNICIAN PROGRAMS, JUSTIFICATION…

  1. Archaeoseismological Study of Prehistoric Earthquakes in Anhui Province, China and Adjacent Areas

    NASA Astrophysics Data System (ADS)

    Yao, D.; Shen, X.; Gong, X.; Wu, W.; Hu, Z.; Zheng, H.; Chen, A.; Zhao, P.; Yang, Y.

    2014-12-01

    Damaging earthquakes on faults typically recur at intervals of centuries to millennia but the seismographs that record them have only been around for about hundred years. Complete records of earthquakes of Ms5 or above for Anhui Province of China and its adjacent areas began in 1336 and most previous records were lost. To reduce the hazard from earthquakes we need a longer record of them than can be provided from such instruments. Archaeoseismological evidence has the potential to determine earthquake activity over millennial time spans, especially when integrated with historical documents and geological evidence. In recent years, taking advantage of large-scale civil excavations, our research team including earthquake and archaeological scientists have cataloged, identified, and analyzed deformation relics of the late-Quaternary period, especially the Neolithic Age. Prehistoric earthquake traces were found in the cultural layers of the Western Zhou Dynasty and the Spring and Autumn Period in Southwest Anhui, the late Dawenkou cultural period in North Anhui, and the Eastern Zhou in South Henan. Along the segment of the Tanlu Fault Zone on the border of Jiangsu-Anhui Provinces, several rapid deformation events mainly in the form of oblique translational thrust had occurred since Late Pleistocene, which was confirmed by microscopic studies. The research findings have partly filled the gap of earthquake records in the area and enriched research methodologies in archaeology, prehistoric earthquakes and earthquake prediction. The project was sponsored by China Earthquake Science Special Research Funding Program (#201308012)

  2. Dating the late prehistoric dispersal of Polynesians to New Zealand using the commensal Pacific rat

    PubMed Central

    Wilmshurst, Janet M.; Anderson, Atholl J.; Higham, Thomas F. G.; Worthy, Trevor H.

    2008-01-01

    The pristine island ecosystems of East Polynesia were among the last places on Earth settled by prehistoric people, and their colonization triggered a devastating transformation. Overhunting contributed to widespread faunal extinctions and the decline of marine megafauna, fires destroyed lowland forests, and the introduction of the omnivorous Pacific rat (Rattus exulans) led to a new wave of predation on the biota. East Polynesian islands preserve exceptionally detailed records of the initial prehistoric impacts on highly vulnerable ecosystems, but nearly all such studies are clouded by persistent controversies over the timing of initial human colonization, which has resulted in proposed settlement chronologies varying from ≈200 B.C. to 1000 A.D. or younger. Such differences underpin radically divergent interpretations of human dispersal from West Polynesia and of ecological and social transformation in East Polynesia and ultimately obfuscate the timing and patterns of this process. Using New Zealand as an example, we provide a reliable approach for accurately dating initial human colonization on Pacific islands by radiocarbon dating the arrival of the Pacific rat. Radiocarbon dates on distinctive rat-gnawed seeds and rat bones show that the Pacific rat was introduced to both main islands of New Zealand ≈1280 A.D., a millennium later than previously assumed. This matches with the earliest-dated archaeological sites, human-induced faunal extinctions, and deforestation, implying there was no long period of invisibility in either the archaeological or palaeoecological records. PMID:18523023

  3. New method development in prehistoric stone tool research: evaluating use duration and data analysis protocols.

    PubMed

    Evans, Adrian A; Macdonald, Danielle A; Giusca, Claudiu L; Leach, Richard K

    2014-10-01

    Lithic microwear is a research field of prehistoric stone tool (lithic) analysis that has been developed with the aim to identify how stone tools were used. It has been shown that laser scanning confocal microscopy has the potential to be a useful quantitative tool in the study of prehistoric stone tool function. In this paper, two important lines of inquiry are investigated: (1) whether the texture of worn surfaces is constant under varying durations of tool use, and (2) the development of rapid objective data analysis protocols. This study reports on the attempt to further develop these areas of study and results in a better understanding of the complexities underlying the development of flexible analytical algorithms for surface analysis. The results show that when sampling is optimised, surface texture may be linked to contact material type, independent of use duration. Further research is needed to validate this finding and test an expanded range of contact materials. The use of automated analytical protocols has shown promise but is only reliable if sampling location and scale are defined. Results suggest that the sampling protocol reports on the degree of worn surface invasiveness, complicating the ability to investigate duration related textural characterisation.

  4. Prehistoric introduction of domestic pigs onto the Okinawa Islands: ancient mitochondrial DNA evidence.

    PubMed

    Watanobe, Takuma; Ishiguro, Naotaka; Nakano, Masuo; Takamiya, Hiroto; Matsui, Akira; Hongo, Hitomi

    2002-08-01

    Ancient DNAs of Sus scrofa specimens excavated from archaeological sites on the Okinawa islands were examined to clarify the genetic relationships among prehistoric Sus scrofa, modern wild boars and domestic pigs inhabiting the Ryukyu archipelago, the Japanese islands, and the Asian continent. We extracted remain DNA from 161 bone specimens excavated from 12 archaeological sites on the Okinawa islands and successfully amplified mitochondrial DNA control region fragments from 33 of 161 specimens. Pairwise difference between prehistoric and modern S. scrofa nucleotide sequences showed that haplotypes of the East Asian domestic pig lineage were found from archaeological specimens together with Ryukyu wild boars native to the Ryukyu archipelago. Phylogenetic analysis of 14 ancient sequences (11 haplotypes; 574 bp) indicated that S. scrofa specimens from two Yayoi-Heian sites (Kitahara and Ara shellmiddens) and two Recent Times sites (Wakuta Kiln and Kiyuna sites) are grouped with modern East Asian domestic pigs. Sus scrofa specimens from Shimizu shellmidden (Yayoi-Heian Period) were very closely related to modern Sus scrofa riukiuanus but had a unique nucleotide insertion, indicating that the population is genetically distinct from the lineage of modern Ryukyu wild boars. This genetic evidence suggests that domestic pigs from the Asian continent were introduced to the Okinawa islands in the early Yayoi-Heian period (1700-2000 BP), or earlier.

  5. Corticomedular index of the right tibia in the diagnosis of osteopenia in prehistoric skeletal remains.

    PubMed

    Gonzalez-Reimers, E; Velasco-Vazquez, J; Barros-Lopez, N; Arnay-De-La-Rosa, M; Santolaria-Fernandez, F; Castilla-Garcia, A

    1998-01-01

    This study examined the diagnostic accuracy of the corticomedular index obtained at the midpoint of the shaft of right tibia as an indicator of osteopenia in a prehistoric sample composed of 133 individuals. Osteopenia was assessed by a histomorphometrical measure of trabecular bone volume (TBV) in an undecalcified bone section of a small part of the proximal epiphysis to: Mild, moderate, and severe osteopenia were defined as TBV values less than 17.5%, 15%, and 12.5%, respectively. The corticomedular index (CI) was determined on X-ray films of the tibiae. Mean TBV of the sample was 17.93 ± 4.97%, it was moderately correlated with CI (r = 0.43, p < 0.0001). CI values under 0.20 showed high specificity in the diagnosis of all degrees of osteopenia, whereas CI values under 0.275 showed relatively high sensitivity (90.4%) in the diagnosis of severe osteopenia. These methods were then prospectively applied in a further sample of 41 right tibiae also from a prehistoric sample of Gran Canaria. The results were similar to those in the larger sample. Thus, CI may be a useful tool in detecting osteopenia in earlier populations. Am. J. Hum. Biol. 10:37-44, 1998. © 1998 Wiley-Liss, Inc. Copyright © 1998 Wiley-Liss, Inc.

  6. Introduction: social complexity and the bow in the prehistoric North American record.

    PubMed

    Bingham, Paul M; Souza, Joanne; Blitz, John H

    2013-01-01

    This Special Issue of Evolutionary Anthropology grew out of a symposium at the 2012 Society for American Archaeology (SAA) meeting in Memphis, Tennessee (April 18-22). The goal of the symposium was to explore what we will argue is one of the most important and promising opportunities in the global archeological enterprise. In late prehistoric North America, the initial rise of cultures of strikingly enhanced complexity and the local introduction of a novel weapon technology, the bow, apparently correlate intimately in a diverse set of independent cases across the continent, as originally pointed out by Blitz. If this empirical relationship ultimately proves robust, it gives us an unprecedented opportunity to evaluate hypotheses for the causal processes producing social complexity and, by extension, to assess the possibility of a universal theory of history. The rise of comparably complex cultures was much more recent in North America than it was elsewhere and the resulting fresher archeological record is relatively well explored. These and other features make prehistoric North America a unique empirical environment. Together, the symposium and this issue have brought together outstanding investigators with both empirical and theoretical expertise. The strong cross-feeding and extended interactions between these investigators have given us all the opportunity to advance the promising exploration of what we call the North American Neolithic transitions. Our goal in this paper is to contextualize this issue. Copyright © 2013 Wiley Periodicals, Inc.

  7. Prehistorical tropical cyclones inferred from washover deposits in the Gulf of Exmouth (W Australia)

    NASA Astrophysics Data System (ADS)

    May, Simon Matthias; Brill, Dominik; Leopold, Matthias; Callow, Nik; Engel, Max; Pint, Anna; Scheffers, Anja; Brückner, Helmut

    2015-04-01

    The NW Australian coast is impacted by 1-2 tropical cyclones (TCs) making landfall per year, and ten historical tsunamis are recorded since 1858. Notwithstanding, little is known about the geological imprint of both (pre)historical TCs and tsunamis in NW Australia in general. Past coastal flooding events may be inferred from geomorphic and sedimentary archives, i.e. in the form of particular landforms (beach ridges, washover fans), deposits (washover sediments in lagoons) or erosional features. Here we present new data on the sedimentology and chronostratigraphy of prehistorical washover events found in geological archives in the NW part of Western Australia. Along the W coast of the Exmouth Gulf, distinct lobate washover fans consist of shell debris layers, sand, coarse coral fragments and entire shells and exhibit delta-type sedimentation patterns. Using ground penetrating radar, unmanned aerial vehicle survey techniques as well as geomorphological and sedimentological investigations, multiple reactivation of the washover fans due to strong TCs is inferred from their complex pattern of accumulation and incision and a minimum of three palaeosols. Each of the palaeosols indicate one major depositional event and a subsequent period of geomorphological stability. Our study aims at (i) providing a detailed characterization of the washover fans' geomorphology and stratigraphical architecture; (ii) documenting the depositional processes involved in the formation of the fans; and (iii) presenting a consistent OSL-based chronostratigraphy spanning the last ~2000 a, showing how OSL can be a key in establishing late Holocene event chronologies.

  8. Fully depleted back illuminated CCD

    DOEpatents

    Holland, Stephen Edward

    2001-01-01

    A backside illuminated charge coupled device (CCD) is formed of a relatively thick high resistivity photon sensitive silicon substrate, with frontside electronic circuitry, and an optically transparent backside ohmic contact for applying a backside voltage which is at least sufficient to substantially fully deplete the substrate. A greater bias voltage which overdepletes the substrate may also be applied. One way of applying the bias voltage to the substrate is by physically connecting the voltage source to the ohmic contact. An alternate way of applying the bias voltage to the substrate is to physically connect the voltage source to the frontside of the substrate, at a point outside the depletion region. Thus both frontside and backside contacts can be used for backside biasing to fully deplete the substrate. Also, high resistivity gaps around the CCD channels and electrically floating channel stop regions can be provided in the CCD array around the CCD channels. The CCD array forms an imaging sensor useful in astronomy.

  9. Charge depletion in organic heterojunction

    NASA Astrophysics Data System (ADS)

    Ng, T. W.; Lo, M. F.; Lee, S. T.; Lee, C. S.

    2012-03-01

    Until now two types of organic-organic heterojunction (OHJ) have been observed in P-N junctions formed between undoped-organic semiconductors. Charge-transfers across OHJs are either negligible or showing electron transfer from P-type to N-type materials, leading to charges accumulation near the interface. Here, we observed that junction of 4,4',4''-tris(2-methylphenyl-phenylamino)triphenylamine (m-MTDATA)/bathocuproine (BCP) show the third-behavior. Electrons in BCP (N-type) transfer to m-MTDATA (P-type), leading to depletion of mobile majority carriers near the junction. While "depletion junctions" are typical in inorganic semiconductors, there are no reports in undoped-OHJ. Formation mechanism of depletion OHJs and fundamental differences between inorganic and organic HJs are discussed.

  10. Agriculture Education. Agricultural Metal Working.

    ERIC Educational Resources Information Center

    Stuttgart Public Schools, AR.

    This curriculum guide is designed for group instruction of secondary agricultural education students enrolled in one or two semester-long courses in agricultural metal working. The guide presents units of study in the following areas: (1) oxyacetylene welding, (2) arc welding, (3) sheet metal, (4) blueprint reading for welders and (5) job…

  11. Agricultural Energy Practices. Agriculture Energy.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with agricultural energy practices. Its objective is for the student to be able to discuss energy use and conservation of resources in the production of agricultural products. Some topics covered are basic uses of direct energy in…

  12. Agriculture Education. Agricultural Metal Working.

    ERIC Educational Resources Information Center

    Stuttgart Public Schools, AR.

    This curriculum guide is designed for group instruction of secondary agricultural education students enrolled in one or two semester-long courses in agricultural metal working. The guide presents units of study in the following areas: (1) oxyacetylene welding, (2) arc welding, (3) sheet metal, (4) blueprint reading for welders and (5) job…

  13. Agricultural Energy Practices. Agriculture Energy.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with agricultural energy practices. Its objective is for the student to be able to discuss energy use and conservation of resources in the production of agricultural products. Some topics covered are basic uses of direct energy in…

  14. Riverine settlement in the evolution of prehistoric land-use systems in the Middle Rio Grande Valley, New Mexico

    Treesearch

    Joseph A. Tainter; Bonnie Bagley Tainter

    1996-01-01

    Ecosystem management should be based on the fullest possible knowledge of ecological structures and processes. In prehistoric North America, the involvement of Indian populations in ecosystem processes ranged from inadvertent alteration of the distribution and abundance of species to large-scale management of landscapes. The knowledge needed to manage ecosystems today...

  15. Agricultural Geophysics

    USDA-ARS?s Scientific Manuscript database

    The four geophysical methods predominantly used for agricultural purposes are resistivity, electromagnetic induction, ground penetrating radar (GPR), and time domain reflectometry (TDR). Resistivity and electromagnetic induction methods are typically employed to map lateral variations of apparent so...

  16. Agriculture Sectors

    EPA Pesticide Factsheets

    The Agriculture sectors comprise establishments primarily engaged in growing crops, raising animals, and harvesting fish and other animals. Find information on compliance, enforcement and guidance on EPA laws and regulations on the NAICS 111 & 112 sectors.

  17. Agricultural Microbiology.

    ERIC Educational Resources Information Center

    Brill, Winston J.

    1981-01-01

    Elucidates strategies for applying microbiological techniques to traditional agricultural practices. Discusses the manipulation of microorganisms that live with plants and also the problems involved in the introduction of new genes into crop plants by recombinant DNA methods. (CS)

  18. Agricultural Microbiology.

    ERIC Educational Resources Information Center

    Brill, Winston J.

    1981-01-01

    Elucidates strategies for applying microbiological techniques to traditional agricultural practices. Discusses the manipulation of microorganisms that live with plants and also the problems involved in the introduction of new genes into crop plants by recombinant DNA methods. (CS)

  19. Agricultural Waste.

    PubMed

    Shu, Huajie; Zhang, Panpan; Chang, Chein-Chi; Wang, Renqing; Zhang, Shuping

    2015-10-01

    The management and disposal of agricultural waste are drawn more and more attention because of the increasing yields and negative effects on the environment. However, proper treatments such as converting abundant biomass wastes into biogas through anaerobic digestion technology, can not only avoid the negative impacts, but also convert waste into available resources. This review summarizes the studies of nearly two hundred scholars from the following four aspects: the characterization, reuse, treatment, and management of agricultural waste.

  20. Towards a strontium isoscape for the determination of provenance of prehistoric wooden findings

    NASA Astrophysics Data System (ADS)

    Horsky, Monika; Tintner, Johannes; Bolka, Monika; Grabner, Michael; Kowarik, Kerstin; Reschreiter, Hans; Kern, Anton; Horacek, Micha; Prohaska, Thomas

    2014-05-01

    Prehistoric wood artefacts have been excavated from ancient salt mine galleries in Hallstatt, Austria. These findings present a unique archive of information on Bronze and Iron Age mining and trade relations, as for certain tools a production elsewhere and transport to the mine is assumed. These wooden artefacts contain the geochemical information of their growth location, though masked by secondary salts due to the storage conditions. Consequently, the analysis of the biogenic 87Sr/86Sr isotope ratios of the findings was carried out in comparison to the respective signatures of trees from possible regions of origin, in order to draw conclusions on prehistoric trade routes. Thus - in addition to Hallstatt - seven regions in the Alpine region of Austria as well as in the Northern and Southern lowlands were selected based on known settlements in the time period of interest. Within all regions, the geological bedrock variability was considered for the definition of sampling spots, which resulted in a total of 26 locations. Four tree species represented in the archaeological finds (i.e. Picea abies, Abies alba, Fagus sylvatica and Quercus sp.) were sampled upon availability. Wood sample digests from eight replicate trees per location were analysed using multicollector-inductively coupled plasma-mass spectrometry (MC-ICP-MS). In order to reveal the biogenic signatures of the prehistoric findings, a decontamination method based on acid leaching was developed. We could successfully separate biogenic from secondary Sr and adopted a mixing theory to account for possibly incomplete removal of the latter. The Sr isotope ratio data obtained from modern trees (i.e. bioavailable Sr) reflect the geological heterogeneity of the Alps, which challenges the creation of an isoscape and its applicability to distinct provenance determination. Different geologic bedrock types can be clearly distinguished by their 87Sr/86Sr, e.g. marine sedimentary and igneous rocks. Furthermore, the data

  1. An assessment of health and disease in the prehistoric inhabitants of the Mariana Islands.

    PubMed

    Pietrusewsky, M; Douglas, M T; Ikehara-Quebral, R M

    1997-11-01

    Using a variety of skeletal and dental stress indicators, an assessment of the health and disease of the indigenous inhabitants of the Mariana Islands, the Chamorro, is made. The major hypothesis to be tested is that the Chamorro were relatively healthy and that deviations from the expected, as well as inter-island variation, may reflect environmental, ecological, and cultural differences. The major skeletal series surveyed include sites on Guam (N = 247 individuals), Rota (N = 14), Tinian (N = 20), and Saipan (N = 102). The majority of the specimens are from the transitional pre-Latte (AD 1-1000) and Latte (AD 1000-1521) periods. These data derive primarily from unpublished osteological reports. The indicators of health and disease surveyed include mortality and paleodemographic data, stature, dental paleopathology, cribra orbitalia, limb bone fractures, degenerative osteoarthritis, and infectious disease (including treponemal infection). Where appropriate, tests of significance are calculated to determine the presence of any patterning in the differences observed within and between the skeletal series. Information recorded in prehistoric Hawaiians provides a standard for external comparisons. Several of the larger skeletal series surveyed have paleodemographic features that are consistent with long-term cemetery populations. Females and subadults are typically underrepresented. Most subadult deaths occur in the 2-5 year age interval. Life expectancy at birth ranges from 26.4 to 33.7 years. A healthy fertility rate is indicated for these series. The prehistoric inhabitants of the Mariana Islands were relatively tall, exceeding living Chamorros measured in the early part of the present century. The greater prevalence of developmental defects in the enamel suggests that the Chamorro were exposed to more stress than prehistoric Hawaiians. The low frequency of cribra orbitalia further indicates iron deficiency anemia was not a problem. There are generally low

  2. Agriculture: About EPA's National Agriculture Center

    EPA Pesticide Factsheets

    EPA's National Agriculture Center (Ag Center), with the support of the United States Department of Agriculture, serves growers, livestock producers, other agribusinesses, and agricultural information/education providers.

  3. Prehistorical and historical declines in Caribbean coral reef accretion rates driven by loss of parrotfish

    NASA Astrophysics Data System (ADS)

    Cramer, Katie L.; O'Dea, Aaron; Clark, Tara R.; Zhao, Jian-Xin; Norris, Richard D.

    2017-01-01

    Caribbean coral reefs have transformed into algal-dominated habitats over recent decades, but the mechanisms of change are unresolved due to a lack of quantitative ecological data before large-scale human impacts. To understand the role of reduced herbivory in recent coral declines, we produce a high-resolution 3,000 year record of reef accretion rate and herbivore (parrotfish and urchin) abundance from the analysis of sediments and fish, coral and urchin subfossils within cores from Caribbean Panama. At each site, declines in accretion rates and parrotfish abundance were initiated in the prehistorical or historical period. Statistical tests of direct cause and effect relationships using convergent cross mapping reveal that accretion rates are driven by parrotfish abundance (but not vice versa) but are not affected by total urchin abundance. These results confirm the critical role of parrotfish in maintaining coral-dominated reef habitat and the urgent need for restoration of parrotfish populations to enable reef persistence.

  4. Prehistorical and historical declines in Caribbean coral reef accretion rates driven by loss of parrotfish

    PubMed Central

    Cramer, Katie L.; O'Dea, Aaron; Clark, Tara R.; Zhao, Jian-xin; Norris, Richard D.

    2017-01-01

    Caribbean coral reefs have transformed into algal-dominated habitats over recent decades, but the mechanisms of change are unresolved due to a lack of quantitative ecological data before large-scale human impacts. To understand the role of reduced herbivory in recent coral declines, we produce a high-resolution 3,000 year record of reef accretion rate and herbivore (parrotfish and urchin) abundance from the analysis of sediments and fish, coral and urchin subfossils within cores from Caribbean Panama. At each site, declines in accretion rates and parrotfish abundance were initiated in the prehistorical or historical period. Statistical tests of direct cause and effect relationships using convergent cross mapping reveal that accretion rates are driven by parrotfish abundance (but not vice versa) but are not affected by total urchin abundance. These results confirm the critical role of parrotfish in maintaining coral-dominated reef habitat and the urgent need for restoration of parrotfish populations to enable reef persistence. PMID:28112169

  5. Prehistorical and historical declines in Caribbean coral reef accretion rates driven by loss of parrotfish.

    PubMed

    Cramer, Katie L; O'Dea, Aaron; Clark, Tara R; Zhao, Jian-Xin; Norris, Richard D

    2017-01-23

    Caribbean coral reefs have transformed into algal-dominated habitats over recent decades, but the mechanisms of change are unresolved due to a lack of quantitative ecological data before large-scale human impacts. To understand the role of reduced herbivory in recent coral declines, we produce a high-resolution 3,000 year record of reef accretion rate and herbivore (parrotfish and urchin) abundance from the analysis of sediments and fish, coral and urchin subfossils within cores from Caribbean Panama. At each site, declines in accretion rates and parrotfish abundance were initiated in the prehistorical or historical period. Statistical tests of direct cause and effect relationships using convergent cross mapping reveal that accretion rates are driven by parrotfish abundance (but not vice versa) but are not affected by total urchin abundance. These results confirm the critical role of parrotfish in maintaining coral-dominated reef habitat and the urgent need for restoration of parrotfish populations to enable reef persistence.

  6. Variations of late prehistoric houses in coastal Northwest Alaska: a view from Wales.

    PubMed

    Harritt, Roger K

    2010-01-01

    A review of literature and archival images reveals a distinctive method of double-walled house construction that predominated at the Beach site at Wales, Alaska, minimally from early contact through ca. 1930. Prior studies have suggested that this house construction form was a widespread convention during the contact period; however, this paper demonstrates that this was not the case. The only other occurrence of this house construction form was a kashim at St. Michael observed by Nelson in the late nineteenth century. The double-walled house represents a set of traits that form a fundamental aspect of the ethnic and group identity of the Kiatanamiut occupants of the Beach site. Recent excavations at Kurigitavik Mound have, however, uncovered remains of a house that is consistent with the double walled construction form. Full documentation of this house awaits the completion of an ongoing excavation and the new data will illuminate the relations between the Kashigitagmiut, Kiatanamiut, and Agianamiut in late prehistoric times.

  7. Paleoepidemiolgical patterns of trauma in a prehistoric population from central California.

    PubMed

    Jurmain, R

    2001-05-01

    Skeletal trauma was investigated in a large collection of human remains from central California (N = 162 aged and sexed adults). Lesions investigated included cranial and long bone fractures, projectile wounds, and dislocation. Long bone fractures were found in 10.5% of individuals; overall, incidence by element was 2.3%. In addition, cranial injuries were found in 4.4% of complete adult crania. Projectile wounds were seen unambiguously in four individuals (with embedded obsidian fragments) and strongly suggested in two other individuals with partially healed lesions. Finally, one case of traumatic hip dislocation was also observed. In both incidence and patterning of injuries, this population is similar to other archeological groups from California. This evidence further supports earlier reports indicating that interpersonal aggression was quite common in prehistoric California.

  8. Ancient jades map 3,000 years of prehistoric exchange in Southeast Asia.

    PubMed

    Hung, Hsiao-Chun; Iizuka, Yoshiyuki; Bellwood, Peter; Nguyen, Kim Dung; Bellina, Bérénice; Silapanth, Praon; Dizon, Eusebio; Santiago, Rey; Datan, Ipoi; Manton, Jonathan H

    2007-12-11

    We have used electron probe microanalysis to examine Southeast Asian nephrite (jade) artifacts, many archeologically excavated, dating from 3000 B.C. through the first millennium A.D. The research has revealed the existence of one of the most extensive sea-based trade networks of a single geological material in the prehistoric world. Green nephrite from a source in eastern Taiwan was used to make two very specific forms of ear pendant that were distributed, between 500 B.C. and 500 A.D., through the Philippines, East Malaysia, southern Vietnam, and peninsular Thailand, forming a 3,000-km-diameter halo around the southern and eastern coastlines of the South China Sea. Other Taiwan nephrite artifacts, especially beads and bracelets, were distributed earlier during Neolithic times throughout Taiwan and from Taiwan into the Philippines.

  9. [The mystery of prehistoric trepanations: Is neurosurgery the world eldest profession?].

    PubMed

    Chauvet, D; Sainte-Rose, C; Boch, A-L

    2010-10-01

    Trepanation is known to be the first surgical procedure ever performed. Its origins date from the Neolithic Age in Europe and the operation was particularly performed in South America at the Pre-Colombian era, a few thousand years later. Based on many archeological studies on trepanned skulls, we compare the differences and similarities of these two periods through epidemiological, topographical, and technical approaches. Signs of bony regeneration are assessed in an attempt to understand the postoperative survival of trepanned patients. The literature in surgery and archeology does not mention the possible relation between trepanations and growing skull fractures. However, it is reasonable to think that these cranial holes, occurring after a pediatric skull fracture, could mimic real trepanation orifices. The possible connections between these two entities are discussed. The etiological hypotheses on prehistoric trepanation are reviewed.

  10. Using metrology in early prehistoric stone tool research: further work and a brief instrument comparison.

    PubMed

    Evans, A A; Macdonald, D

    2011-01-01

    Early prehistoric research aims to discover the activities of our ancestors and piece together the process of evolution and sociocultural development. A key element in this process is the study of stone tools, particularly how these tools functioned in prehistory. Currently, there are no established quantitative methods that address stone tool function. This article provides a summary of previous studies using metrological methods in stone tool research and details the use of laser scanning confocal microscopy to conduct areal surface analysis using three-dimensional data sets. Research to-date is preliminary but promising and shows that microscopic metrological approaches can provide a quantitative method to identify how stone tools were used. A limited comparison of two metrological systems is presented, the results of which highlight a need for caution and further investigation on the comparability of related data sets.

  11. Ancient mitochondrial genome reveals trace of prehistoric migration in the east Pamir by pastoralists.

    PubMed

    Ning, Chao; Gao, Shizhu; Deng, Boping; Zheng, Hongxiang; Wei, Dong; Lv, Haoze; Li, Hongjie; Song, Li; Wu, Yong; Zhou, Hui; Cui, Yinqiu

    2016-02-01

    The complete mitochondrial genome of one 700-year-old individual found in Tashkurgan, Xinjiang was target enriched and sequenced in order to shed light on the population history of Tashkurgan and determine the phylogenetic relationship of haplogroup U5a. The ancient sample was assigned to a subclade of haplogroup U5a2a1, which is defined by two rare and stable transversions at 16114A and 13928C. Phylogenetic analysis shows a distribution pattern for U5a2a that is indicative of an origin in the Volga-Ural region and exhibits a clear eastward geographical expansion that correlates with the pastoral culture also entering the Eurasian steppe. The haplogroup U5a2a present in the ancient Tashkurgan individual reveals prehistoric migration in the East Pamir by pastoralists. This study shows that studying an ancient mitochondrial genome is a useful approach for studying the evolutionary process and population history of Eastern Pamir.

  12. Biochemical evidence of cannibalism at a prehistoric Puebloan site in southwestern Colorado.

    PubMed

    Marlar, R A; Leonard, B L; Billman, B R; Lambert, P M; Marlar, J E

    2000-09-07

    The existence of cannibalism is one of the most controversial issues in the archaeology of the American Southwest. Disarticulated, cut-marked and heat-altered human remains from non-burial contexts at prehistoric Puebloan (Anasazi) archaeological sites in the Four Corners region of the American Southwest have been interpreted by some scholars as evidence of cannibalism. Osteological studies indicate that many of the disarticulated bodies found at these sites were processed in a manner consistent with food preparation. Opponents of this interpretation point out that non-cannibalistic practices such as secondary interment, corpse mutilation and ritualized witch executions might account for the assemblages. Osteological evidence alone does not document the actual ingestion of human flesh. Here we show consumption of human flesh did occur as demonstrated in preserved human waste containing identifiable human tissue remains from a site with osteological evidence of cannibalism.

  13. [The evolutionist fallacy of early visitors. Analogies between 'primitive peoples' and prehistoric man in medical historiography].

    PubMed

    Bruchhausen, Walter

    2006-01-01

    Accounts of 'prehistoric medicine' and 'ethnomedicine' have sometimes led to conclusions by analogy in medical historiography that are seen as highly problematic in modern cultural anthropology. However, this review of medical historical writings of the last three centuries shows that evolutionist identifications of early with foreign medicine were not a permanent trait of medical historiography. This approach flourished mainly in the climate of certain movements or periods that were characterised by fanatical belief in progress and by social utopias: the French Revolution, Darwinism and the period of industrial expansion in Germany, and National Socialism. Medical historiography shared this problematic approach with contemporary (social and cultural) anthropology, and - despite this methodological misuse - both acknowledged the legitimacy or even requirement of studying also similarities in the development of different periods and cultures.

  14. Nutrition and health at contact in late prehistoric central Gulf Coast Florida.

    PubMed

    Hutchinson, Dale L; Norr, Lynette

    2006-03-01

    This paper presents an analysis of human remains from Tatham Mound, a dual-component mortuary site from central Gulf Coast Florida. The human remains from Tatham are significant because they come from a limited time period during the initial contact with Europeans at AD 1525-1550. Dietary reconstruction demonstrates that at the time of European contact, maize was not a predominant dietary item. Low frequencies for several dental and skeletal pathological indicators are consistent with relatively good health as compared to other Southeastern late prehistoric and protohistoric populations. Despite the limited time period represented by the mound population, critical interactions occurred between Native Americans and Spaniards, as indicated by skeletal elements severed by metal weapons. The Tatham population is significant because it is one of the earliest studied populations contacted by Europeans in North America, and the only one with well-documented sharp-force trauma that represents intergroup hostility. (c) 2005 Wiley-Liss, Inc.

  15. Determining the magnitude, frequency and source of prehistoric events - Is there a Holy Grail?

    NASA Astrophysics Data System (ADS)

    Goff, James; Dominey-Howes, Dale; Chague-Goff, Catherine; Strotz, Luke; Anning, David; Bird, Deanne; Calgaro, Emma; Courtney, Claire

    2010-05-01

    Over the last five years there has been a growing body of literature on efforts to try and identify evidence for prehistoric precursors of the 2004 Indian Ocean Tsunami. Similar work is also being carried out in many parts of the World and evidence for palaeotsunamis is slowly emerging - this is commendable. In some cases extensive databases for individual events have been, and continue to be, assembled. The Storegga Slide off Norway is probably the most comprehensive dataset collated for a single event and provides an excellent example of how the source and magnitude of a prehistoric tsunami can be assessed. As an increasing amount of information is gathered a growing number of palaeotsunamis are being recognised as "hybrids" - events that are historic in one country and prehistoric in another. The 1700AD Cascadia event is probably the most well-known of these, although the 1575AD Chilean tsunami is another one of increasing importance. Hybrid tsunamis help us to better understand the nature and extent of palaeotsunamis in regions with short historical records - Pacific Island nations are an excellent example. Globally, we are recognising that the study of contemporary tsunamis is a multi-disciplinary field. Not surprisingly, the same applies to palaeotsunamis. The collation and interpretation of data for these prehistoric events however, is fraught with difficulties and currently nearly every palaeotsunami database that has been developed consists almost entirely of geological data. In an increasingly multidisciplinary field this is severely limiting. We provide three examples from the New Zealand palaeotsunami database - one includes a range of multidisciplinary data for a local event, another is a distantly sourced hybrid, and the final one looks at regional source identification using multiple contemporaneous deposits. This is quite a remarkable dataset, but it throws up some interesting issues. To be able to effectively identify regional and distant

  16. Ancient jades map 3,000 years of prehistoric exchange in Southeast Asia

    PubMed Central

    Hung, Hsiao-Chun; Iizuka, Yoshiyuki; Bellwood, Peter; Nguyen, Kim Dung; Bellina, Bérénice; Silapanth, Praon; Dizon, Eusebio; Santiago, Rey; Datan, Ipoi; Manton, Jonathan H.

    2007-01-01

    We have used electron probe microanalysis to examine Southeast Asian nephrite (jade) artifacts, many archeologically excavated, dating from 3000 B.C. through the first millennium A.D. The research has revealed the existence of one of the most extensive sea-based trade networks of a single geological material in the prehistoric world. Green nephrite from a source in eastern Taiwan was used to make two very specific forms of ear pendant that were distributed, between 500 B.C. and 500 A.D., through the Philippines, East Malaysia, southern Vietnam, and peninsular Thailand, forming a 3,000-km-diameter halo around the southern and eastern coastlines of the South China Sea. Other Taiwan nephrite artifacts, especially beads and bracelets, were distributed earlier during Neolithic times throughout Taiwan and from Taiwan into the Philippines. PMID:18048347

  17. Prehistoric demographic fluctuations in China inferred from radiocarbon data and their linkage with climate change over the past 50,000 years

    NASA Astrophysics Data System (ADS)

    Wang, Can; Lu, Houyuan; Zhang, Jianping; Gu, Zhaoyan; He, Keyang

    2014-08-01

    Historic human-climate interactions have been of interest to scholars for a long time. However, exploring the long-term relation between prehistoric demography and climate change remains challenging because of the absence of an effective proxy for population reconstruction. Recently, the summed probability distribution of archaeological radiocarbon dates has been widely used as a proxy for human population levels, although researchers recognize that such usage must be cautious. This approach is rarely applied in China due to the lack of a comprehensive archaeological radiocarbon database, and thus the relation between human population and climate change in China remains ambiguous. Herein we systematically compile an archaeological 14C database (n = 4656) for China for the first time. Using the summed probability distributions of the radiocarbon dates alongside high-resolution palaeoclimatic records, we show that: 1) the commencement of major population expansion in China was at 9 ka cal BP, occurring after the appearance of agriculture and associated with the early Holocene climate amelioration; 2) the major periods of small population size and population decline, i.e., 46-43 ka cal BP, 41-38 ka cal BP, 31-28.6 ka cal BP, 25-23.5 ka cal BP, 18-15.2 ka cal BP, and 13-11.4 ka cal BP, correspond well with the dating of abrupt cold events in the Last Glacial (LG) such as the Heinrich and Younger Dryas (YD) events, while the major periods of high-level population in the Holocene, i.e., 8.5-7 ka cal BP, 6.5-5 ka cal BP and 4.3-2.8 ka cal BP, occur at the same times as warm-moist conditions and Neolithic cultural prosperity, suggesting that abrupt cooling in the climate profoundly limited population size and that mild climate episodes spurred a growth in prehistoric populations and advances in human cultures; and 3) populations in different regions experience different growth trajectories and that their responses to climate change are varied, due to both regional

  18. Stone tools from the ancient Tongan state reveal prehistoric interaction centers in the Central Pacific

    PubMed Central

    Clark, Geoffrey R.; Reepmeyer, Christian; Melekiola, Nivaleti; Woodhead, Jon; Dickinson, William R.; Martinsson-Wallin, Helene

    2014-01-01

    Tonga was unique in the prehistoric Pacific for developing a maritime state that integrated the archipelago under a centralized authority and for undertaking long-distance economic and political exchanges in the second millennium A.D. To establish the extent of Tonga’s maritime polity, we geochemically analyzed stone tools excavated from the central places of the ruling paramounts, particularly lithic artifacts associated with stone-faced chiefly tombs. The lithic networks of the Tongan state focused on Samoa and Fiji, with one adze sourced to the Society Islands 2,500 km from Tongatapu. To test the hypothesis that nonlocal lithics were especially valued by Tongan elites and were an important source of political capital, we analyzed prestate lithics from Tongatapu and stone artifacts from Samoa. In the Tongan state, 66% of worked stone tools were long-distance imports, indicating that interarchipelago connections intensified with the development of the Tongan polity after A.D. 1200. In contrast, stone tools found in Samoa were from local sources, including tools associated with a monumental structure contemporary with the Tongan state. Network analysis of lithics entering the Tongan state and of the distribution of Samoan adzes in the Pacific identified a centralized polity and the products of specialized lithic workshops, respectively. These results indicate that a significant consequence of social complexity was the establishment of new types of specialized sites in distant geographic areas. Specialized sites were loci of long-distance interaction and formed important centers for the transmission of information, people, and materials in prehistoric Oceania. PMID:25002481

  19. Evidence for Prehistoric Origins of Egyptian Mummification in Late Neolithic Burials

    PubMed Central

    Jones, Jana; Higham, Thomas F. G.; Oldfield, Ron; O'Connor, Terry P.; Buckley, Stephen A.

    2014-01-01

    Traditional theories on ancient Egyptian mummification postulate that in the prehistoric period (i.e. the Neolithic and Chalcolithic periods, 5th and 4th millennia B.C.) bodies were naturally desiccated through the action of the hot, dry desert sand. Although molding of the body with resin-impregnated linen is believed to be an early Pharaonic forerunner to more complex processes, scientific evidence for the early use of resins in artificial mummification has until now been limited to isolated occurrences during the late Old Kingdom (c. 2200 B.C.), their use becoming more apparent during the Middle Kingdom (c. 2000-1600 BC). We examined linen wrappings from bodies in securely provenanced tombs (pit graves) in the earliest recorded ancient Egyptian cemeteries at Mostagedda in the Badari region (Upper Egypt). Our investigations of these prehistoric funerary wrappings using a combination of gas chromatography-mass spectrometry (GC-MS) and thermal desorption/pyrolysis (TD/Py)-GC-MS have identified a pine resin, an aromatic plant extract, a plant gum/sugar, a natural petroleum source, and a plant oil/animal fat in directly AMS-dated funerary wrappings. Predating the earliest scientific evidence by more than a millennium, these embalming agents constitute complex, processed recipes of the same natural products, in similar proportions, as those utilized at the zenith of Pharaonic mummification some 3,000 years later. The antibacterial properties of some of these ingredients and the localized soft-tissue preservation that they would have afforded lead us to conclude that these represent the very beginnings of experimentation that would evolve into the famous mummification practice of the Pharaonic period. PMID:25118605

  20. Stone tools from the ancient Tongan state reveal prehistoric interaction centers in the Central Pacific.

    PubMed

    Clark, Geoffrey R; Reepmeyer, Christian; Melekiola, Nivaleti; Woodhead, Jon; Dickinson, William R; Martinsson-Wallin, Helene

    2014-07-22

    Tonga was unique in the prehistoric Pacific for developing a maritime state that integrated the archipelago under a centralized authority and for undertaking long-distance economic and political exchanges in the second millennium A.D. To establish the extent of Tonga's maritime polity, we geochemically analyzed stone tools excavated from the central places of the ruling paramounts, particularly lithic artifacts associated with stone-faced chiefly tombs. The lithic networks of the Tongan state focused on Samoa and Fiji, with one adze sourced to the Society Islands 2,500 km from Tongatapu. To test the hypothesis that nonlocal lithics were especially valued by Tongan elites and were an important source of political capital, we analyzed prestate lithics from Tongatapu and stone artifacts from Samoa. In the Tongan state, 66% of worked stone tools were long-distance imports, indicating that interarchipelago connections intensified with the development of the Tongan polity after A.D. 1200. In contrast, stone tools found in Samoa were from local sources, including tools associated with a monumental structure contemporary with the Tongan state. Network analysis of lithics entering the Tongan state and of the distribution of Samoan adzes in the Pacific identified a centralized polity and the products of specialized lithic workshops, respectively. These results indicate that a significant consequence of social complexity was the establishment of new types of specialized sites in distant geographic areas. Specialized sites were loci of long-distance interaction and formed important centers for the transmission of information, people, and materials in prehistoric Oceania.

  1. Evidence for prehistoric origins of Egyptian mummification in late Neolithic burials.

    PubMed

    Jones, Jana; Higham, Thomas F G; Oldfield, Ron; O'Connor, Terry P; Buckley, Stephen A

    2014-01-01

    Traditional theories on ancient Egyptian mummification postulate that in the prehistoric period (i.e. the Neolithic and Chalcolithic periods, 5th and 4th millennia B.C.) bodies were naturally desiccated through the action of the hot, dry desert sand. Although molding of the body with resin-impregnated linen is believed to be an early Pharaonic forerunner to more complex processes, scientific evidence for the early use of resins in artificial mummification has until now been limited to isolated occurrences during the late Old Kingdom (c. 2200 B.C.), their use becoming more apparent during the Middle Kingdom (c. 2000-1600 BC). We examined linen wrappings from bodies in securely provenanced tombs (pit graves) in the earliest recorded ancient Egyptian cemeteries at Mostagedda in the Badari region (Upper Egypt). Our investigations of these prehistoric funerary wrappings using a combination of gas chromatography-mass spectrometry (GC-MS) and thermal desorption/pyrolysis (TD/Py)-GC-MS have identified a pine resin, an aromatic plant extract, a plant gum/sugar, a natural petroleum source, and a plant oil/animal fat in directly AMS-dated funerary wrappings. Predating the earliest scientific evidence by more than a millennium, these embalming agents constitute complex, processed recipes of the same natural products, in similar proportions, as those utilized at the zenith of Pharaonic mummification some 3,000 years later. The antibacterial properties of some of these ingredients and the localized soft-tissue preservation that they would have afforded lead us to conclude that these represent the very beginnings of experimentation that would evolve into the famous mummification practice of the Pharaonic period.

  2. Stone tools from the ancient Tongan state reveal prehistoric interaction centers in the Central Pacific

    NASA Astrophysics Data System (ADS)

    Clark, Geoffrey R.; Reepmeyer, Christian; Melekiola, Nivaleti; Woodhead, Jon; Dickinson, William R.; Martinsson-Wallin, Helene

    2014-07-01

    Tonga was unique in the prehistoric Pacific for developing a maritime state that integrated the archipelago under a centralized authority and for undertaking long-distance economic and political exchanges in the second millennium A.D. To establish the extent of Tonga's maritime polity, we geochemically analyzed stone tools excavated from the central places of the ruling paramounts, particularly lithic artifacts associated with stone-faced chiefly tombs. The lithic networks of the Tongan state focused on Samoa and Fiji, with one adze sourced to the Society Islands 2,500 km from Tongatapu. To test the hypothesis that nonlocal lithics were especially valued by Tongan elites and were an important source of political capital, we analyzed prestate lithics from Tongatapu and stone artifacts from Samoa. In the Tongan state, 66% of worked stone tools were long-distance imports, indicating that interarchipelago connections intensified with the development of the Tongan polity after A.D. 1200. In contrast, stone tools found in Samoa were from local sources, including tools associated with a monumental structure contemporary with the Tongan state. Network analysis of lithics entering the Tongan state and of the distribution of Samoan adzes in the Pacific identified a centralized polity and the products of specialized lithic workshops, respectively. These results indicate that a significant consequence of social complexity was the establishment of new types of specialized sites in distant geographic areas. Specialized sites were loci of long-distance interaction and formed important centers for the transmission of information, people, and materials in prehistoric Oceania.

  3. Regional strategies for the accelerating global problem of groundwater depletion

    NASA Astrophysics Data System (ADS)

    Aeschbach-Hertig, Werner; Gleeson, Tom

    2012-12-01

    Groundwater--the world's largest freshwater resource--is critically important for irrigated agriculture and hence for global food security. Yet depletion is widespread in large groundwater systems in both semi-arid and humid regions of the world. Excessive extraction for irrigation where groundwater is slowly renewed is the main cause of the depletion, and climate change has the potential to exacerbate the problem in some regions. Globally aggregated groundwater depletion contributes to sea-level rise, and has accelerated markedly since the mid-twentieth century. But its impacts on water resources are more obvious at the regional scale, for example in agriculturally important parts of India, China and the United States. Food production in such regions can only be made sustainable in the long term if groundwater levels are stabilized. To this end, a transformation is required in how we value, manage and characterize groundwater systems. Technical approaches--such as water diversion, artificial groundwater recharge and efficient irrigation--have failed to balance regional groundwater budgets. They need to be complemented by more comprehensive strategies that are adapted to the specific social, economic, political and environmental settings of each region.

  4. Ozone Depletion from Nearby Supernovae

    NASA Technical Reports Server (NTRS)

    Gehrels, Neil; Laird, Claude M.; Jackman, Charles H.; Cannizzo, John K.; Mattson, Barbara J.; Chen, Wan; Bhartia, P. K. (Technical Monitor)

    2002-01-01

    Estimates made in the 1970's indicated that a supernova occurring within tens of parsecs of Earth could have significant effects on the ozone layer. Since that time improved tools for detailed modeling of atmospheric chemistry have been developed to calculate ozone depletion, and advances have been made also in theoretical modeling of supernovae and of the resultant gamma ray spectra. In addition, one now has better knowledge of the occurrence rate of supernovae in the galaxy, and of the spatial distribution of progenitors to core-collapse supernovae. We report here the results of two-dimensional atmospheric model calculations that take as input the spectral energy distribution of a supernova, adopting various distances from Earth and various latitude impact angles. In separate simulations we calculate the ozone depletion due to both gamma rays and cosmic rays. We find that for the combined ozone depletion from these effects roughly to double the 'biologically active' UV flux received at the surface of the Earth, the supernova must occur at approximately or less than 8 parsecs.

  5. Ozone depletion, paradigms, and politics

    SciTech Connect

    Iman, R.L.

    1993-10-01

    The destruction of the Earth`s protective ozone layer is a prime environmental concern. Industry has responded to this environmental problem by: implementing conservation techniques to reduce the emission of ozone-depleting chemicals (ODCs); using alternative cleaning solvents that have lower ozone depletion potentials (ODPs); developing new, non-ozone-depleting solvents, such as terpenes; and developing low-residue soldering processes. This paper presents an overview of a joint testing program at Sandia and Motorola to evaluate a low-residue (no-clean) soldering process for printed wiring boards (PWBs). Such processes are in widespread use in commercial applications because they eliminate the cleaning operation. The goal of this testing program was to develop a data base that could be used to support changes in the mil-specs. In addition, a joint task force involving industry and the military has been formed to conduct a follow-up evaluation of low-residue processes that encompass the concerns of the tri-services. The goal of the task force is to gain final approval of the low-residue technology for use in military applications.

  6. Agricultural Biodiversity.

    ERIC Educational Resources Information Center

    Postance, Jim

    1998-01-01

    The extinction of farm animals and crops is rarely brought up during discussions of endangered species and biodiversity; however, the loss of diversity in crops and livestock threatens the sustainability of agriculture. Presents three activities: (1) "The Colors of Diversity"; (2) "Biodiversity among Animals"; and (3) "Heirloom Plants." Discusses…

  7. AGRICULTURAL EXTENSION.

    ERIC Educational Resources Information Center

    FARQUHAR, R.N.

    AUSTRALIAN AGRICULTURAL EXTENSION HAS LONG EMPHASIZED TECHNICAL ADVISORY SERVICE AT THE EXPENSE OF THE SOCIOECONOMIC ASPECTS OF FARM PRODUCTION AND FARM LIFE. ONLY IN TASMANIA HAS FARM MANAGEMENT BEEN STRESSED. DEMANDS FOR THE WHOLE-FARM APPROACH HAVE PRODUCED A TREND TOWARD GENERALISM FOR DISTRICT OFFICERS IN MOST STATES. THE FEDERAL GOVERNMENT,…

  8. Agricultural Biodiversity.

    ERIC Educational Resources Information Center

    Postance, Jim

    1998-01-01

    The extinction of farm animals and crops is rarely brought up during discussions of endangered species and biodiversity; however, the loss of diversity in crops and livestock threatens the sustainability of agriculture. Presents three activities: (1) "The Colors of Diversity"; (2) "Biodiversity among Animals"; and (3) "Heirloom Plants." Discusses…

  9. AGRICULTURAL EDUCATION.

    ERIC Educational Resources Information Center

    STEVENS, GLENN Z.

    FEDERAL LEGISLATION HAS PROVIDED FOR PUBLIC PROGRAMS OF OCCUPATIONAL AGRICULTURE EDUCATION IN LAND GRANT COLLEGES AND UNIVERSITIES, LOCAL SCHOOL DISTRICTS, AND MANPOWER DEVELOPMENT PROGRAMS. PROGRAM OBJECTIVES SHOULD BE TO DEVELOP KNOWLEDGE AND SKILLS, PROVIDE OCCUPATIONAL GUIDANCE AND PLACEMENT, AND DEVELOP ABILITIES IN HUMAN RELATIONS AND…

  10. Issues in Stratospheric Ozone Depletion.

    NASA Astrophysics Data System (ADS)

    Lloyd, Steven Andrew

    Following the announcement of the discovery of the Antarctic ozone hole in 1985 there have arisen a multitude of questions pertaining to the nature and consequences of polar ozone depletion. This thesis addresses several of these specific questions, using both computer models of chemical kinetics and the Earth's radiation field as well as laboratory kinetic experiments. A coupled chemical kinetic-radiative numerical model was developed to assist in the analysis of in situ field measurements of several radical and neutral species in the polar and mid-latitude lower stratosphere. Modeling was used in the analysis of enhanced polar ClO, mid-latitude diurnal variation of ClO, and simultaneous measurements of OH, HO_2, H_2 O and O_3. Most importantly, such modeling was instrumental in establishing the link between the observed ClO and BrO concentrations in the Antarctic polar vortex and the observed rate of ozone depletion. The principal medical concern of stratospheric ozone depletion is that ozone loss will lead to the enhancement of ground-level UV-B radiation. Global ozone climatology (40^circS to 50^ circN latitude) was incorporated into a radiation field model to calculate the biologically accumulated dosage (BAD) of UV-B radiation, integrated over days, months, and years. The slope of the annual BAD as a function of latitude was found to correspond to epidemiological data for non-melanoma skin cancers for 30^circ -50^circN. Various ozone loss scenarios were investigated. It was found that a small ozone loss in the tropics can provide as much additional biologically effective UV-B as a much larger ozone loss at higher latitudes. Also, for ozone depletions of > 5%, the BAD of UV-B increases exponentially with decreasing ozone levels. An important key player in determining whether polar ozone depletion can propagate into the populated mid-latitudes is chlorine nitrate, ClONO_2 . As yet this molecule is only indirectly accounted for in computer models and field

  11. The plight of arid land agriculture

    SciTech Connect

    Hinman, C. W.; Hinman, K.W.

    1992-01-01

    This book analyses the problems of the agricultural environment worldwide and possible solutions. Problems covered include the following: famines caused by agricultural land mismanegment in Subsaharan Africa and population increase; improved productivity leading to salinity, erosion, and water depletion; toxic wastes; loging, deforestation, and over-grazing. Agricultural practices, both ancient and modern, in arid lands are described. Food crops suited for arid lands, potential industrial crops, oil extraction from seed and rubber extraction, and biomass as a source of energy are discussed in different chapters. Finally the book deals with optimization of water use, prevention of salinization, and the prospect of global warming.

  12. Agricultural field reclamation utilizing native grass crop production

    Treesearch

    J. Cure

    2013-01-01

    Developing a method of agricultural field reclamation to native grasses in the Lower San Pedro Watershed could prove to be a valuable tool for educational and practical purposes. Agricultural field reclamation utilizing native grass crop production will address water table depletion, soil degradation and the economic viability of the communities within the watershed....

  13. Physiological implications of anthropogenic environmental calcium depletion

    Treesearch

    Catherine H. Borer; Paul G. Schaberg; Donald H. DeHayes; Gary J. Hawley

    2001-01-01

    Recent evidence indicates that numerous anthropogenic factors can deplete calcium (Ca) from forested ecosystems. Although it is difficult to quantify the extent of this depletion, some reports indicate that the magnitude of Ca losses may be substantial. The potential for Ca depletion raises important questions about tree health. Only a fraction of foliar Ca is...

  14. Exposure to nature counteracts aggression after depletion.

    PubMed

    Wang, Yan; She, Yihan; Colarelli, Stephen M; Fang, Yuan; Meng, Hui; Chen, Qiuju; Zhang, Xin; Zhu, Hongwei

    2017-08-31

    Acts of self-control are more likely to fail after previous exertion of self-control, known as the ego depletion effect. Research has shown that depleted participants behave more aggressively than non-depleted participants, especially after being provoked. Although exposure to nature (e.g., a walk in the park) has been predicted to replenish resources common to executive functioning and self-control, the extent to which exposure to nature may counteract the depletion effect on aggression has yet to be determined. The present study investigated the effects of exposure to nature on aggression following depletion. Aggression was measured by the intensity of noise blasts participants delivered to an ostensible opponent in a competition reaction-time task. As predicted, an interaction occurred between depletion and environmental manipulations for provoked aggression. Specifically, depleted participants behaved more aggressively in response to provocation than non-depleted participants in the urban condition. However, provoked aggression did not differ between depleted and non-depleted participants in the natural condition. Moreover, within the depletion condition, participants in the natural condition had lower levels of provoked aggression than participants in the urban condition. This study suggests that a brief period of nature exposure may restore self-control and help depleted people regain control over aggressive urges. © 2017 Wiley Periodicals, Inc.

  15. Multielemental analysis of prehistoric animal teeth by laser-induced breakdown spectroscopy and laser ablation inductively coupled plasma mass spectrometry

    SciTech Connect

    Galiova, Michaela; Kaiser, Jozef; Fortes, Francisco J.; Novotny, Karel; Malina, Radomir; Prokes, Lubomir; Hrdlicka, Ales; Vaculovic, Tomas; Nyvltova Fisakova, Miriam; Svoboda, Jiri; Kanicky, Viktor; Laserna, Javier J.

    2010-05-01

    Laser-induced breakdown spectroscopy (LIBS) and laser ablation (LA) inductively coupled plasma (ICP) mass spectrometry (MS) were utilized for microspatial analyses of a prehistoric bear (Ursus arctos) tooth dentine. The distribution of selected trace elements (Sr, Ba, Fe) was measured on a 26 mmx15 mm large and 3 mm thick transverse cross section of a canine tooth. The Na and Mg content together with the distribution of matrix elements (Ca, P) was also monitored within this area. The depth of the LIBS craters was measured with an optical profilometer. As shown, both LIBS and LA-ICP-MS can be successfully used for the fast, spatially resolved analysis of prehistoric teeth samples. In addition to microchemical analysis, the sample hardness was calculated using LIBS plasma ionic-to-atomic line intensity ratios of Mg (or Ca). To validate the sample hardness calculations, the hardness was also measured with a Vickers microhardness tester.

  16. The Case of Ozone Depletion

    NASA Technical Reports Server (NTRS)

    Lambright, W. Henry

    2005-01-01

    While the National Aeronautics and Space Administration (NASA) is widely perceived as a space agency, since its inception NASA has had a mission dedicated to the home planet. Initially, this mission involved using space to better observe and predict weather and to enable worldwide communication. Meteorological and communication satellites showed the value of space for earthly endeavors in the 1960s. In 1972, NASA launched Landsat, and the era of earth-resource monitoring began. At the same time, in the late 1960s and early 1970s, the environmental movement swept throughout the United States and most industrialized countries. The first Earth Day event took place in 1970, and the government generally began to pay much more attention to issues of environmental quality. Mitigating pollution became an overriding objective for many agencies. NASA's existing mission to observe planet Earth was augmented in these years and directed more toward environmental quality. In the 1980s, NASA sought to plan and establish a new environmental effort that eventuated in the 1990s with the Earth Observing System (EOS). The Agency was able to make its initial mark via atmospheric monitoring, specifically ozone depletion. An important policy stimulus in many respects, ozone depletion spawned the Montreal Protocol of 1987 (the most significant international environmental treaty then in existence). It also was an issue critical to NASA's history that served as a bridge linking NASA's weather and land-resource satellites to NASA s concern for the global changes affecting the home planet. Significantly, as a global environmental problem, ozone depletion underscored the importance of NASA's ability to observe Earth from space. Moreover, the NASA management team's ability to apply large-scale research efforts and mobilize the talents of other agencies and the private sector illuminated its role as a lead agency capable of crossing organizational boundaries as well as the science-policy divide.

  17. A simulation model for migrations and dispersals of prehistoric human populations.

    PubMed

    Ohba, T; Masaki, M; Ohtsuka, R

    1990-01-01

    A new simulation model was constructed to estimate demographic processes of prehistoric human populations who migrated and dispersed, particularly to uninhabited habitats. The characteristics of the simulation model are: the minimum component is an individual with sex and age properties; each individual's death is determined in each year by comparing the age-specific probability of dying and a random number; childbirth of each woman of reproductive age in each year is determined by the age-specific probability of childbirth and a random number; sex ratio at birth is fixed at 1.05, and each newborn baby's sex is determined by a random number; people live in settlements; each settlement is located in a cell on a hexagonal-linkage land and the cells temporarily number 64 (8x8); each cell has its own optimal carrying capacity; and the net reproduction rate (NRR) is used for determining the speed of population increase in each cell. The preliminary trial applied the following conditions: 64 cells, carrying capacity of each cell is 160, age-specific probability of dying was based on the life table of prehistoric Maori in New Zealand (infant mortality rate of 157/1000 and life expectancy of 23.49 years). 500-year-interval changes of the total population of all cells increased almost exponentially to the year 2000 from 346 persons at year 500 to 2208 at year 2000. It gradually increased further and peaked at about 10,000 at the year 5000. By year 8000 all the cells were inhabited with a total population of 10,978. The population in the year 2000 was 27.6 times more than in year zero. The intergenerational interval of 25 years yielded a NRR of 1.042. During the period between the year 2000 and the year 4000 the population increased by 3.42 times corresponding to a NRR of 1.015. After the year 5000 population increase declined to almost zero with a NRR of almost 1.00. Preliminary trials have produced satisfactory results.

  18. Could the Health Decline of Prehistoric California Indians be Related to Exposure to Polycyclic Aromatic Hydrocarbons (PAHs) from Natural Bitumen?

    PubMed Central

    Sholts, Sabrina B.; Erlandson, Jon M.; Gjerdrum, Thor; Westerholm, Roger

    2011-01-01

    Background: The negative health effects of polycyclic aromatic hydrocarbons (PAHs) are well established for modern human populations but have so far not been studied in prehistoric contexts. PAHs are the main component of fossil bitumen, a naturally occurring material used by past societies such as the Chumash Indians in California as an adhesive, as a waterproofing agent, and for medicinal purposes. The rich archaeological and ethnohistoric record of the coastal Chumash suggests that they were exposed to multiple uptake pathways of bituminous PAHs, including direct contact, fume inhalation, and oral uptake from contaminated water and seafood. Objectives: We investigated the possibility that PAHs from natural bitumen compromised the health of the prehistoric Chumash Indians in California. Conclusions: Exposure of the ancient Chumash Indians to toxic PAHs appears to have gradually increased across a period of 7,500 years because of an increased use of bitumen in the Chumash technology, together with a dietary shift toward PAH-contaminated marine food. Skeletal analysis indicates a concurrent population health decline that may be related to PAH uptake. However, establishing such a connection is virtually impossible without knowing the actual exposure levels experienced by these populations. Future methodological research may provide techniques for determining PAH levels in ancient skeletal material, which would open new avenues for research on the health of prehistoric populations and on the long-term effects of human PAH exposure. PMID:21596651

  19. Could the health decline of prehistoric California indians be related to exposure to polycyclic aromatic hydrocarbons (PAHs) from natural bitumen?

    PubMed

    Wärmländer, Sebastian K T S; Sholts, Sabrina B; Erlandson, Jon M; Gjerdrum, Thor; Westerholm, Roger

    2011-09-01

    The negative health effects of polycyclic aromatic hydrocarbons (PAHs) are well established for modern human populations but have so far not been studied in prehistoric contexts. PAHs are the main component of fossil bitumen, a naturally occurring material used by past societies such as the Chumash Indians in California as an adhesive, as a waterproofing agent, and for medicinal purposes. The rich archaeological and ethnohistoric record of the coastal Chumash suggests that they were exposed to multiple uptake pathways of bituminous PAHs, including direct contact, fume inhalation, and oral uptake from contaminated water and seafood. We investigated the possibility that PAHs from natural bitumen compromised the health of the prehistoric Chumash Indians in California. Exposure of the ancient Chumash Indians to toxic PAHs appears to have gradually increased across a period of 7,500 years because of an increased use of bitumen in the Chumash technology, together with a dietary shift toward PAH-contaminated marine food. Skeletal analysis indicates a concurrent population health decline that may be related to PAH uptake. However, establishing such a connection is virtually impossible without knowing the actual exposure levels experienced by these populations. Future methodological research may provide techniques for determining PAH levels in ancient skeletal material, which would open new avenues for research on the health of prehistoric populations and on the long-term effects of human PAH exposure.

  20. Combining ER and GPR surveys for evidence of prehistoric landscape construction: case study at Mound City, Ohio, USA

    NASA Astrophysics Data System (ADS)

    Schneider, B. B.; Mandel, R. D.; Tsoflias, G. P.; De Vore, S. L.; Lynott, M.

    2016-06-01

    Mound City, located at the Hopewell Culture National Historical Park in south-central Ohio, USA, is a prehistoric earthwork (200 BC-500 AD) that consists of 24 mounds enclosed in a square embankment wall and is surrounded by eight pits. Recent excavation of two of these pits resulted in the discovery of a clay loam liner that appears to have been placed on the floor of the pits by a prehistoric society known as the Hopewell. The aim of this study was to determine the spatial pattern of this liner in one of the pits using non-invasive geophysical techniques, specifically electrical resistivity and ground-penetrating radar. Minimally invasive soil augers and a test trench yielded information that was used to corroborate interpretations of the geophysical data. The geophysical methods proved to be useful in locating and defining the remnants of the prehistoric clay loam liner, and the results of our investigation indicate that almost 50% of the liner still remains in the pit today. This discovery supports a new interpretation that the Hopewell excavated and preserved the pits at the Mound City site because they served as cultural landscape features.

  1. Recognizing and dating prehistoric liquefaction features: Lessons learned in the New Madrid seismic zone, central United States

    USGS Publications Warehouse

    Tuttle, M.P.; Schweig, E.S.

    1996-01-01

    The New Madrid seismic zone (NMSZ), which experienced severe liquefaction during the great New Madrid, Missouri, earthquakes of 1811 and 1812 as well as during several prehistoric earthquakes, is a superb laboratory for the study of world-class, arthquake-induced liquefaction features and their use in paleoseismology. In seismically active regions like the NMSZ, frequent large earthquakes can produce a complex record of liquefaction events that is difficult to interpret. Lessons learned studying liquefaction features in the NMSZ may help to unravel the paleoseismic record in other seismically active regions. Soil characteristics of liquefaction features, as well as their structural and sratigraphic relations to Native American occupation horizons and other cultural features, an help to distinguish prehistoric liquefaction features from historic features. In addition, analyses of artifact assemblages and botanical content of cultural horizons can help to narrow the age ranges of liquefaction features. Future research should focus on methods for defining source areas and estimating magnitudes of prehistoric earthquakes from liquefaction features. Also, new methods for dating liquefaction features are needed.

  2. Some thoughts on the factors that controlled prehistoric maize production in the American Southwest with application to southwestern Colorado

    USGS Publications Warehouse

    Benson, L.V.; Ramsey, D.K.; Stahle, D.W.; Petersen, K.L.

    2013-01-01

    In this paper, we present a model of prehistoric southwestern Colorado maize productivity. The model is based on a tree-ring reconstruction of water-year precipitation for Mesa Verde for the period A.D. 480 to 2011. Correlation of historic Mesa Verde precipitation with historic precipitation at 11 other weather stations enabled the construction of an elevation-dependent precipitation function. Prehistoric water-year precipitation values for Mesa Verde together with the elevation-dependent precipitation function allowed construction of the elevation of southwest Colorado precipitation contours for each year since A.D. 480, including the 30-cm contour, which represents the minimum amount of precipitation necessary for the production of maize and the 50-cm contour, which represents the optimum amount of precipitation necessary for the production of maize. In this paper, calculations of prehistoric maize productivity and field life for any specific elevation are also demonstrated. These calculations were performed using organic nitrogen measurements made on seven southwestern Colorado soil groups together with values of reconstructed water-year precipitation and estimations of the organic nitrogen mineralization rate.

  3. Evaluating groundwater depletion as computed by a global water model

    NASA Astrophysics Data System (ADS)

    Schuh, Carina; Doell, Petra; Mueller Schmied, Hannes; Portmann, Felix

    2013-04-01

    When groundwater abstraction occurs faster than its replenishment over a long time and in a large area, the result is an overexploitation or depletion of groundwater. The problem is aggravated in areas where a growing population relies on freshwater resources for an intensive irrigation agriculture that is meant to guarantee food security. Especially in semi-arid and arid regions, the dominant use for groundwater is irrigation, reaching more than 95% of total water use. Therefore, the hot spots for groundwater depletion are the world's major irrigation areas like the central United States, north-western India and north China. Groundwater depletion presents a major threat to securing agricultural productivity and domestic water supply in these parts of the world. Besides, the environmental consequences that accompany the abstraction of groundwater are severe. Within the scientific community there is a common understanding that high-quality data on globally existing groundwater resources are deficient. In order to allow a sustainable management of the world's available groundwater resources, especially in areas under current water stress, the quantification of groundwater depletion is of high importance. WaterGAP (Water - Global Assessment and Prognosis) is a global model of water availability and water use which can serve to estimate the impact of groundwater and surface water withdrawals on groundwater storage. The new WaterGAP version 2.2a was modified to allow for an improved analysis of groundwater storage changes in semi-arid and arid regions. Now, groundwater recharge from surface water bodies is simulated in semi-arid and arid areas. Estimation of net groundwater abstractions was modified with respect of irrigation water use efficiency for groundwater and return flow fractions. In addition, irrigation consumptive use has been set to 70% of optimal irrigation consumptive use, assuming deficit irrigation to prevail in these parts of the world. Based on time

  4. Biomedical consequences of ozone depletion

    NASA Astrophysics Data System (ADS)

    Coohill, Thomas P.

    1994-07-01

    It is widely agreed that a portion of the earth's protective stratospheric ozone layer is being depleted. The major effect of this ozone loss will be an increase in the amount of ultraviolet radiation (UV reaching the biosphere. This increase will be completely contained within the UVB (290nm - 320nm). It is imperative that assessments be made of the effects of this additional UVB on living organisms. This requires a detailed knowledge of the UVB photobiology of these life forms. One analytical technique to aid in the approximations is the construction of UV action spectra for such important biological end-points as human skin cancer, cataracts, immune suppression; plant photosynthesis and crop yields; and aquatic organism responses to UVB, especially the phytoplankton. Combining these action spectra with the known solar spectrum (and estimates for various ozone depletion scenarios) can give rise to a series of effectiveness spectra for these parameters. This manuscript gives a first approximation, rough estimate, for the effectiveness spectra for some of these bioresponses, and a series of crude temporary values for how a 10% ozone loss would affect the above end-points. These are not intended to masquerade as final answers, but rather, to serve as beginning attempts for a process which should be continually refined. It is hoped that these estimates will be of some limited use to agencies, such as government and industry, that have to plan now for changes in human activities that might alter future atmospheric chemistry in a beneficial manner.

  5. A diffusion based study of population dynamics: Prehistoric migrations into South Asia

    PubMed Central

    Vahia, Mayank N.; Yadav, Nisha; Ladiwala, Uma; Mathur, Deepak

    2017-01-01

    A diffusion equation has been used to study migration of early humans into the South Asian subcontinent. The diffusion equation is tempered by a set of parameters that account for geographical features like proximity to water resources, altitude, and flatness of land. The ensuing diffusion of populations is followed in time-dependent computer simulations carried out over a period of 10,000 YBP. The geographical parameters are determined from readily-available satellite data. The results of our computer simulations are compared to recent genetic data so as to better correlate the migratory patterns of various populations; they suggest that the initial populations started to coalesce around 4,000 YBP before the commencement of a period of relative geographical isolation of each population group. The period during which coalescence of populations occurred appears consistent with the established timeline associated with the Harappan civilization and also, with genetic admixing that recent genetic mapping data reveal. Our results may contribute to providing a timeline for the movement of prehistoric people. Most significantly, our results appear to suggest that the Ancestral Austro-Asiatic population entered the subcontinent through an easterly direction, potentially resolving a hitherto-contentious issue. PMID:28493906

  6. Environmental productivity predicts migration, demographic, and linguistic patterns in prehistoric California.

    PubMed

    Codding, Brian F; Jones, Terry L

    2013-09-03

    Global patterns of ethnolinguistic diversity vary tremendously. Some regions show very little variation even across vast expanses, whereas others exhibit dense mosaics of different languages spoken alongside one another. Compared with the rest of Native North America, prehistoric California exemplified the latter. Decades of linguistic, genetic, and archaeological research have produced detailed accounts of the migrations that aggregated to build California's diverse ethnolinguistic mosaic, but there have been few have attempts to explain the process underpinning these migrations and why such a mosaic did not develop elsewhere. Here we show that environmental productivity predicts both the order of migration events and the population density recorded at contact. The earliest colonizers occupied the most suitable habitats along the coast, whereas subsequent Mid-Late Holocene migrants settled in more marginal habitats. Other Late Holocene patterns diverge from this trend, reflecting altered dynamics linked to food storage and increased sedentism. Through repeated migration events, incoming populations replaced resident populations occurring at lower densities in lower-productivity habitats, thereby resulting in the fragmentation of earlier groups and the development of one of the most diverse ethnolinguistic patterns in the Americas. Such a process may account for the distribution of ethnolinguistic diversity worldwide.

  7. EDXRF study of Prehistoric artefacts from Quinta do Almaraz (Cacilhas, Portugal)

    NASA Astrophysics Data System (ADS)

    Araújo, M. Fátima; de Barros, Luís.; Teixeira, Ana Cristina; de Melo, Ana Ávila

    2004-01-01

    This paper presents a non-destructive analytical study by secondary target energy-dispersive X-ray fluorescence spectrometry of selected artefacts found during excavations carried out since 1988, at the archaeological site of "Quinta do Almaraz", Estremadura, West Portugal. The analysed collection was composed by metallic artefacts ( fibulae, fish-hooks, needles, buckle, tweezers, knives, arrowheads), crucibles, slags and metallurgical residues. The chemical composition of the metallic artefacts have made possible to identify different groups belonging to distinct Prehistoric periods, from the Bronze (bronzes) till the Iron (iron-based alloys) Age. Variation in the Sn and Pb percentages in the bronzes pointed out to the existence of three different metallurgical processes, although they did not present different typological characteristics. Semi-quantitative analysis on fragments of crucibles have permitted to identify particular metallurgical operations, namely the preparation of gold alloys and the remains of the silver cupellation process, which was introduced in the Iberian Peninsula by the Phoenician [Early Metal Mining and Production, Smithsonian Institution Press, Washington, DC, 1995].

  8. Ancient mitochondrial lineages support the prehistoric maternal root of Basques in Northern Iberian Peninsula.

    PubMed

    Palencia-Madrid, Leire; Cardoso, Sergio; Keyser, Christine; López-Quintana, Juan Carlos; Guenaga-Lizasu, Amagoia; de Pancorbo, Marian M

    2017-05-01

    The Basque population inhabits the Franco-Cantabrian region in southwest Europe where Palaeolithic human groups took refuge during the Last Glacial Maximum. Basques have been an isolated population, largely considered as one of the most ancient European populations and it is possible that they maintained some pre-Neolithic genetic characteristics. This work shows the results of mitochondrial DNA analysis of seven ancient human remains from the Cave of Santimamiñe in the Basque Country dated from Mesolithic to the Late Roman period. In addition, we compared these data with those obtained from a modern sample of Basque population, 158 individuals that nowadays inhabits next to the cave. The results support the hypothesis that Iberians might have been less affected by the Neolithic mitochondrial lineages carried from the Near East than populations of Central Europe and revealed the unexpected presence of prehistoric maternal lineages such as U5a2a and U3a in the Basque region. Comparison between ancient and current population samples upholds the hypothesis of continuity of the maternal lineages in the area of the Franco-Cantabrian region.

  9. A diffusion based study of population dynamics: Prehistoric migrations into South Asia.

    PubMed

    Vahia, Mayank N; Yadav, Nisha; Ladiwala, Uma; Mathur, Deepak

    2017-01-01

    A diffusion equation has been used to study migration of early humans into the South Asian subcontinent. The diffusion equation is tempered by a set of parameters that account for geographical features like proximity to water resources, altitude, and flatness of land. The ensuing diffusion of populations is followed in time-dependent computer simulations carried out over a period of 10,000 YBP. The geographical parameters are determined from readily-available satellite data. The results of our computer simulations are compared to recent genetic data so as to better correlate the migratory patterns of various populations; they suggest that the initial populations started to coalesce around 4,000 YBP before the commencement of a period of relative geographical isolation of each population group. The period during which coalescence of populations occurred appears consistent with the established timeline associated with the Harappan civilization and also, with genetic admixing that recent genetic mapping data reveal. Our results may contribute to providing a timeline for the movement of prehistoric people. Most significantly, our results appear to suggest that the Ancestral Austro-Asiatic population entered the subcontinent through an easterly direction, potentially resolving a hitherto-contentious issue.

  10. Preliminary environmental historical results to reconstruct prehistoric human-environmental interactions in Eastern Hungary

    NASA Astrophysics Data System (ADS)

    Salisbury, Roderick B.; Bácsmegi, Gábor; Sümegi, Pál

    2013-09-01

    Palaeoenvironmental research is playing an important role in recent archaeological investigations. We present preliminary results of geoarchaeological analyses conducted at a palaeochannel located between two prehistoric archaeological sites in eastern Hungary. The study area lies within the Körös River Basin in Békés County, a region of intensive human occupation beginning in the Neolithic, ca. 7550 BP, and represents only the second palynological analysis done in conjunction with archaeological investigations and adjacent to an archaeological site in the Körös region. Pollen from an environmental monolith was used to reconstruct the local vegetation composition and the human impact on arboreal and non-arboreal vegetation near the archaeological sites. Sediment analyses helped to reconstruct hydrological activity and human impact on the local palaeochannel. Results indicate that activity from the Neolithic onwards played an important role in local environmental change, including increasing sedimentation and deposition of organic matter in the local waterway, some forest clearance and a shift from primarily arboreal vegetation to more grasses on elevated surfaces. The trophic status of the local channel changed several times during the Holocene. In addition, indications that groundwater levels may have been fluctuating during the period of human occupation, when combined with the other changes in the area, provide a possible partial explanation for changing settlement patterns.

  11. Environmental productivity predicts migration, demographic, and linguistic patterns in prehistoric California

    PubMed Central

    Codding, Brian F.; Jones, Terry L.

    2013-01-01

    Global patterns of ethnolinguistic diversity vary tremendously. Some regions show very little variation even across vast expanses, whereas others exhibit dense mosaics of different languages spoken alongside one another. Compared with the rest of Native North America, prehistoric California exemplified the latter. Decades of linguistic, genetic, and archaeological research have produced detailed accounts of the migrations that aggregated to build California’s diverse ethnolinguistic mosaic, but there have been few have attempts to explain the process underpinning these migrations and why such a mosaic did not develop elsewhere. Here we show that environmental productivity predicts both the order of migration events and the population density recorded at contact. The earliest colonizers occupied the most suitable habitats along the coast, whereas subsequent Mid–Late Holocene migrants settled in more marginal habitats. Other Late Holocene patterns diverge from this trend, reflecting altered dynamics linked to food storage and increased sedentism. Through repeated migration events, incoming populations replaced resident populations occurring at lower densities in lower-productivity habitats, thereby resulting in the fragmentation of earlier groups and the development of one of the most diverse ethnolinguistic patterns in the Americas. Such a process may account for the distribution of ethnolinguistic diversity worldwide. PMID:23959871

  12. Using seafaring simulations and shortest-hop trajectories to model the prehistoric colonization of Remote Oceania

    PubMed Central

    Montenegro, Álvaro; Callaghan, Richard T.; Fitzpatrick, Scott M.

    2016-01-01

    The prehistoric colonization of islands in Remote Oceania that began ∼3400 B.P. represents what was arguably the most expansive and ambitious maritime dispersal of humans across any of the world’s seas or oceans. Though archaeological evidence has provided a relatively clear picture of when many of the major island groups were colonized, there is still considerable debate as to where these settlers originated from and their strategies/trajectories used to reach habitable land that other datasets (genetic, linguistic) are also still trying to resolve. To address these issues, we have harnessed the power of high-resolution climatic and oceanographic datasets in multiple seafaring simulation platforms to examine major pulses of colonization in the region. Our analysis, which takes into consideration currents, land distribution, wind periodicity, the influence of El Niño Southern Oscillation (ENSO) events, and “shortest-hop” trajectories, demonstrate that (i) seasonal and semiannual climatic changes were highly influential in structuring ancient Pacific voyaging; (ii) western Micronesia was likely settled from somewhere around the Maluku (Molucca) Islands; (iii) Samoa was the most probable staging area for the colonization of East Polynesia; and (iv) although there are major differences in success rates depending on time of year and the occurrence of ENSO events, settlement of Hawai’i and New Zealand is possible from the Marquesas or Society Islands, the same being the case for settlement of Easter Island from Mangareva or the Marquesas. PMID:27791145

  13. Geoarchaeology of a 'drowning' island: geomorphologic formation and prehistoric human habitation of Funafuti Atoll, Tuvalu

    NASA Astrophysics Data System (ADS)

    Yamaguchi, T.; Kobayashi, R.

    2012-12-01

    There seem to be a variety to vulnerability of atolls. In fact our archaeological investigations of Majuro in Marshall and Funafuti in Tuvalu revealed diverse duration of human settlement histories. The most reliable charcoal ages for earliest human habitation on Oceanic atolls were obtained from Majuro Atoll, which date back to 1800 - 2000 yr. BP, but radiocarbon ages of charcoal samples retrieved from Funafuti and Vaitupu suggest that Tuvalu were inhabited around ca. 500 yr. BP. It should be helpful to examine geomorphic formation of each atoll islet in considering this temporal difference of human settlement histories. During the mid-Holocene period, the paleoreef had grown up to reach the highstand sea level over the bedrock of Pleistocene limestone. The emergence of the Holocene reef is estimated around 2000 yr. BP in the central Pacific, which is viewed as a trigger of depositional process of atoll islets. There is, however, the possibility that the process was not uniform and sedimentation of foraminiferal sand and coral shingle was affected with more local conditions. Several results of our geoarchaeological excavations in Fongafale, Funafuti Atoll, would be related with this topic. Synthesizing them with the late 18th century's topographic information reported by the Royal Society of London, I then discuss a tentative scenario of geomorphologic formation and prehistoric human settlement of Fongafale. The diversity of human settlement histories could be an indicator of the relative vulnerability of atoll islets.

  14. Lake sediments record prehistoric lead pollution related to early copper production in North America.

    PubMed

    Pompeani, David P; Abbott, Mark B; Steinman, Byron A; Bain, Daniel J

    2013-06-04

    The mining and use of copper by prehistoric people on Michigan's Keweenaw Peninsula is one of the oldest examples of metalworking. We analyzed the concentration of lead, titanium, magnesium, iron, and organic matter in sediment cores recovered from three lakes located near mine pits to investigate the timing, location, and magnitude of ancient copper mining pollution. Lead concentrations were normalized to lithogenic metals and organic matter to account for processes that can influence natural (or background) lead delivery. Nearly simultaneous lead enrichments occurred at Lake Manganese and Copper Falls Lake ∼8000 and 7000 years before present (yr BP), indicating that copper extraction occurred concurrently in at least two locations on the peninsula. The poor temporal coherence among the lead enrichments from ∼6300 to 5000 yr BP at each lake suggests that the focus of copper mining and annealing shifted through time. In sediment younger than ∼5000 yr BP, lead concentrations remain at background levels at all three lakes, excluding historic lead increases starting ∼150 yr BP. Our work demonstrates that lead emissions associated with both the historic and Old Copper Complex tradition are detectable and can be used to determine the temporal and geographic pattern of metal pollution.

  15. Testing a simulation model for reconstruction of prehistoric forest-stand dynamics

    SciTech Connect

    Solomon, A.M.; Delcourt, H.R.; West, D.C.; Blasing, T.J.

    1980-01-01

    Three characteristics of the output of a forest-stand simulation model were matched to pollen records of actual vegetation in central Tennessee. Temporal shifts of individual pollen taxon frequencies were compared to shifts of individual plant species frequencies in simulated biomass for the last 16,000 y. Individual pollen profiles (temporally ordered species frequencies) were also compared to simulated biomass profiles during that period. Modern ratios of pollen to vegetation composition (R values) were compared with those calculated from simulated biomass percentages and fossil pollen percentages. The model output was similar to the comparable characteristics of the pollen record. The model output is therefore a plausible description of vegetation characteristics at the site of pollen deposition in central Tennessee. The model produced information unavailable from other sets of prehistoric data. This information describes the invasion and growth of the yellow-poplar which produces no windborne pollen, and of palynologically indistinguishable oak and pine species. These results suggest that many paleoecological questions can be answered through appropriate simulation modeling studies.

  16. Palaeotempestology: the study of prehistoric tropical cyclones--a review and implications for hazard assessment.

    PubMed

    Nott, Jonathan

    2004-05-01

    Records of prehistoric tropical cyclones occur in the form of ridges of coral rubble, sand, shell, sand and shell, and pumice; erosional terraces in raised gravel beaches; barrier washover deposits; and, sediments deposited in the shallow offshore marine environment. Other less well-documented records occur as variations in isotopic ratios within speleothems and possibly tree rings, and changes in pollen records resulting from introduction of new species after forest disturbance due to cyclonic winds. As yet, such records have not been identified beyond 5500 years of age. Recent palaeotempestological studies in the United States and northern Australia have highlighted that the frequency and magnitude of these natural hazards do not remain constant over time, and there are periods when cyclogenesis is enhanced, and others of relative quiescence. Recognition of such regime changes, or non-stationarity in the long-term record, is important for risk assessments of this hazard. Until now however, few if any risk assessments have incorporated data from the long-term record of tropical cyclones, and instead have relied on generally short instrumented historical records. The longer-term records suggest that such an approach may miscalculate the 1% Annual Exceedance Probability risk to coastal communities from future tropical cyclones.

  17. Breast cancer surgery: an historical narrative. Part I. From prehistoric times to Renaissance.

    PubMed

    Sakorafas, George H; Safioleas, Michael

    2009-11-01

    Cancer was known as a disease since prehistoric times. Management of breast cancer evolved slowly through centuries in the ancient world up to the Renaissance. This period is marked by the absence of any scientifically verifiable understanding of the true nature of cancer and its natural history and consequently by a lack of effective treatment. Breast has been considered as a symbol of femininity, fertility and beauty. Hippocrates proposed that breast cancer, among other neoplasms, was a 'systemic disease' caused by an excess of black bile. The humoral theory was further supported by Galen and dominated for centuries in medicine. Fulguration and breast amputation by using various instruments to achieve a rapid operation were widely used up to the 18th century. The Renaissance was a revolutionary period, since it stimulated medical practice; at that time physicians started to scientifically study medicine. Vesalius greatly contributed in the advancement of surgery, and he vigorously opposed Galen's doctrines. Many great surgeons of that time (including Paré, Cabrol, Servetto, Scultetus, Tulp, Fabry von Hilded, etc.) advanced the science of surgery. Interestingly, Bartoleny Gabrol (1590) in Montpellier advocated radical mastectomy, which was popularised by Halsted, 300 years later. However, the lack of anaesthesia and the problem of wound infections (due to the lack of the aseptic techniques) generated significance and often problems for the surgeons of that time. Surgery was often 'heroic' but primitive and even inhumane by current standards. Therapeutic nihilism was the prevailing altitude regarding breast cancer, at least among the vast majority of surgeons.

  18. Optically stimulated luminescence dating of cave deposits at the Xiaogushan prehistoric site, northeastern China.

    PubMed

    Zhang, Jia-Fu; Huang, Wei-Wen; Yuan, Bao-Yin; Fu, Ren-Yi; Zhou, Li-Ping

    2010-11-01

    The Xiaogushan cave site is one of the most important prehistoric sites in North China. The stone and bone artifacts found in the cave are similar to European contemporaneous artifacts. Cave deposits consist of five layers that have been dated from 46,353 ± 1179 to 4229 ± 135 cal. yr BP, using radiocarbon dating techniques on charcoal and bone samples collected from Layers 2-5. In this paper, optically stimulated luminescence (OSL) techniques were applied to date six samples taken from Layers 1-3. The luminescence properties of the fine-grained and coarse-grained quartz extracts indicate that the materials are suitable for OSL dating using a single-aliquot regeneration-dose (SAR) protocol. The OSL ages obtained are broadly consistent with the stratigraphy and the associated calibrated radiocarbon ages. The dating results show that the cave was first occupied by humans about 70 ka. The human occupation of the cave may be related to climate change. An occupation hiatus is inferred to between ∼ 17 to ∼ 10 ka. The stone and bone artifacts found in Layers 2 and 3 may indicate the Middle to Upper Paleolithic transitions in the region.

  19. Edward B. D. Neuhauser Lecture. Paleoradiology of the prehistoric Australian aborigines.

    PubMed

    Kricun, M E

    1994-08-01

    Prehistoric populations suffered the rigors of everyday survival as hunter-gatherers, and some of the individuals had osseous manifestations as a result both of these stresses and of aging. Paleomedical scientists usually seek out osseous abnormalities found in skeletal remains, thus stressing the morbidity of a population [4]. In so doing, they portray those populations as less healthy than their own. This may not necessarily be the case. Specimens without signs of injury should be considered as evidence of the population's vitality; bones with evidence of injury that has healed during life should be considered as evidence of debility; and bones with evidence of conditions that are occupational in origin should be considered as evidence of social, economic, and ecological environmental conditions [4]. This is more useful than singling out specimens with abnormalities as signs of the population's morbidity [4]. This is confirmed by the majority of bones appearing osteologically healthy, except for the characteristic findings of biomechanical wear and tear arising from acquiring food and from combat (osteoarthritis, fractures). Although a number of children may have been infected by the treponematoses, which were manifested by cutaneous lesions, only a small percentage of children actually experienced osseous infection. Also, bone metastases were extremely rare.

  20. Variation in limb proportions between Jomon foragers and Yayoi agriculturalists from prehistoric Japan.

    PubMed

    Temple, Daniel H; Auerbach, Benjamin M; Nakatsukasa, Masato; Sciulli, Paul W; Larsen, Clark Spencer

    2008-10-01

    Variation in limb proportions between prehistoric Jomon and Yayoi people of Japan are explored by this study. Jomon people were the descendents of Pleistocene nomads who migrated to the Japanese Islands around 30,000 yBP. Phenotypic and genotypic evidence indicates that Yayoi people were recent migrants to Japan from continental Northeast Asia who likely interbred with Jomon foragers. Limb proportions of Jomon and Yayoi people were compared using RMA regression and "Quick-Test" calculations to investigate relative variability between these two groups. Cluster and principal components analyses were performed on size-standardized limb lengths and used to compare Jomon and Yayoi people with other groups from various climatic zones. Elongated distal relative to proximal limb lengths were observed among Jomon compared to Yayoi people. Jomon limb proportions were similar to human groups from temperate/tropical climates at lower latitudes, while Yayoi limb proportions more closely resemble groups from colder climates at higher latitudes. Limb proportional similarities with groups from warmer environments among Jomon foragers likely reflect morphological changes following Pleistocene colonization of the Japanese Islands. Cold-derived limb proportions among the Yayoi people likely indicate retention of these traits following comparatively recent migrations to the Japanese Islands. Changes in limb proportions experienced by Jomon foragers and retention of cold-derived limb proportions among Yayoi people conform to previous findings that report changes in these proportions following long-standing evolution in a specific environment.

  1. Conflict and death in a late prehistoric community in the American Midwest.

    PubMed

    Milner, George R; Ferrell, Rebecca J

    2011-01-01

    Over the past two decades, it has been recognized that the effects of intergroup conflict in prehistoric small-scale societies were greater than previously thought. Osteological evidence provides otherwise unobtainable information on the number of people who were killed, and who was most likely to become a casualty. One such site is Norris Farms #36 in the American Midwest, dating to ca. AD 1300. Skeletal evidence of injuries (blunt force trauma and arrow wounds), body mutilation (scalping, decapitation, and dismemberment), and scavenger damage indicate that one-third of the adults died in a series of ambushes, although children were mostly spared. Both young and old adults were killed, and the age distributions of the male and female victims were similar. Individuals with disabilities that interfered with mobility were more likely to be killed than their healthier counterparts. This level of conflict-related mortality almost certainly had an effect on the community's ability to conduct its affairs and, indeed, to survive as a viable economic and social group.

  2. Mitochondrial DNA from prehistoric canids highlights relationships between dogs and South-East European wolves.

    PubMed

    Verginelli, Fabio; Capelli, Cristian; Coia, Valentina; Musiani, Marco; Falchetti, Mario; Ottini, Laura; Palmirotta, Raffaele; Tagliacozzo, Antonio; De Grossi Mazzorin, Iacopo; Mariani-Costantini, Renato

    2005-12-01

    The question of the origins of the dog has been much debated. The dog is descended from the wolf that at the end of the last glaciation (the archaeologically hypothesized period of dog domestication) was one of the most widespread among Holarctic mammals. Scenarios provided by genetic studies range from multiple dog-founding events to a single origin in East Asia. The earliest fossil dogs, dated approximately 17-12,000 radiocarbon ((14)C) years ago (YA), were found in Europe and in the Middle East. Ancient DNA (a-DNA) evidence could contribute to the identification of dog-founder wolf populations. To gain insight into the relationships between ancient European wolves and dogs we analyzed a 262-bp mitochondrial DNA control region fragment retrieved from five prehistoric Italian canids ranging in age from approximately 15,000 to approximately 3,000 (14)C YA. These canids were compared to a worldwide sample of 547 purebred dogs and 341 wolves. The ancient sequences were highly diverse and joined the three major clades of extant dog sequences. Phylogenetic investigations highlighted relationships between the ancient sequences and geographically widespread extant dog matrilines and between the ancient sequences and extant wolf matrilines of mainly East European origin. The results provide a-DNA support for the involvement of European wolves in the origins of the three major dog clades. Genetic data also suggest multiple independent domestication events. East European wolves may still reflect the genetic variation of ancient dog-founder populations.

  3. The creation of prehistoric man. Aimé Rutot and the Eolith controversy, 1900-1920.

    PubMed

    De Bont, Raf

    2003-12-01

    Although he died in obscurity, the Belgian museum conservator Aimé Rutot (1847-1933) was one of the most famous European archaeologists between 1900 and 1920. The focus of his scientific interest was stone flints, which he claimed to be the oldest known human tools, so-called eoliths. Skeptics maintained that the flints showed no marks of human workmanship, but Rutot nevertheless managed to spread his "Eolithic theory" in an important part of the scientific community. This essay demonstrates how material objects--series of stone flints and sets of statues that purported to reconstruct prehistoric "races"--were given scientific meaning by Rutot. Rutot diffused his ideas by disseminating his stones and statues, thus enlarging his networks of influence. For a time he managed to be at the material center of a trade network as well as at the intellectual center of archaeological debate. The essay shows how Rutot achieved this status and how he eventually fell from favor among serious scientists.

  4. Prehistoric birds from New Ireland, Papua New Guinea: Extinctions on a large Melanesian island

    PubMed Central

    Steadman, David W.; White, J. Peter; Allen, Jim

    1999-01-01

    At least 50 species of birds are represented in 241 bird bones from five late Pleistocene and Holocene archaeological sites on New Ireland (Bismarck Archipelago, Papua New Guinea). The bones include only two of seabirds and none of migrant shorebirds or introduced species. Of the 50 species, at least 12 (petrel, hawk, megapode, quail, four rails, cockatoo, two owls, and crow) are not part of the current avifauna and have not been recorded previously from New Ireland. Larger samples of bones undoubtedly would indicate more extirpated species and refine the chronology of extinction. Humans have lived on New Ireland for ca. 35,000 years, whereas most of the identified bones are 15,000 to 6,000 years old. It is suspected that most or all of New Ireland’s avian extinction was anthropogenic, but this suspicion remains undetermined. Our data show that significant prehistoric losses of birds, which are well documented on Pacific islands more remote than New Ireland, occurred also on large, high, mostly forested islands close to New Guinea. PMID:10051683

  5. A South American Prehistoric Mitogenome: Context, Continuity, and the Origin of Haplogroup C1d.

    PubMed

    Sans, Mónica; Figueiro, Gonzalo; Hughes, Cris E; Lindo, John; Hidalgo, Pedro C; Malhi, Ripan S

    2015-01-01

    Based on mitochondrial DNA (mtDNA), it has been estimated that at least 15 founder haplogroups peopled the Americas. Subhaplogroup C1d3 was defined based on the mitogenome of a living individual from Uruguay that carried a lineage previously identified in hypervariable region I sequences from ancient and modern Uruguayan individuals. When complete mitogenomes were studied, additional substitutions were found in the coding region of the mitochondrial genome. Using a complete ancient mitogenome and three modern mitogenomes, we aim to clarify the ancestral state of subhaplogroup C1d3 and to better understand the peopling of the region of the Río de la Plata basin, as well as of the builders of the mounds from which the ancient individuals were recovered. The ancient mitogenome, belonging to a female dated to 1,610±46 years before present, was identical to the mitogenome of one of the modern individuals. All individuals share the mutations defining subhaplogroup C1d3. We estimated an age of 8,974 (5,748-12,261) years for the most recent common ancestor of C1d3, in agreement with the initial peopling of the geographic region. No individuals belonging to the defined lineage were found outside of Uruguay, which raises questions regarding the mobility of the prehistoric inhabitants of the country. Moreover, the present study shows the continuity of Native lineages over at least 6,000 years.

  6. A South American Prehistoric Mitogenome: Context, Continuity, and the Origin of Haplogroup C1d

    PubMed Central

    Sans, Mónica; Figueiro, Gonzalo; Hughes, Cris E.; Lindo, John; Hidalgo, Pedro C.; Malhi, Ripan S.

    2015-01-01

    Based on mitochondrial DNA (mtDNA), it has been estimated that at least 15 founder haplogroups peopled the Americas. Subhaplogroup C1d3 was defined based on the mitogenome of a living individual from Uruguay that carried a lineage previously identified in hypervariable region I sequences from ancient and modern Uruguayan individuals. When complete mitogenomes were studied, additional substitutions were found in the coding region of the mitochondrial genome. Using a complete ancient mitogenome and three modern mitogenomes, we aim to clarify the ancestral state of subhaplogroup C1d3 and to better understand the peopling of the region of the Río de la Plata basin, as well as of the builders of the mounds from which the ancient individuals were recovered. The ancient mitogenome, belonging to a female dated to 1,610±46 years before present, was identical to the mitogenome of one of the modern individuals. All individuals share the mutations defining subhaplogroup C1d3. We estimated an age of 8,974 (5,748–12,261) years for the most recent common ancestor of C1d3, in agreement with the initial peopling of the geographic region. No individuals belonging to the defined lineage were found outside of Uruguay, which raises questions regarding the mobility of the prehistoric inhabitants of the country. Moreover, the present study shows the continuity of Native lineages over at least 6,000 years. PMID:26509686

  7. The Evolution of the Age at Menarche from Prehistorical to Modern Times.

    PubMed

    Papadimitriou, Anastasios

    2016-12-01

    Menarche denotes the onset of the female reproductive capacity. The age that menarche occurs is mostly attributed to the interaction of genetics and various environmental factors. Herein, the author describes the evolution of the age at menarche from prehistoric to the present times. Data from skeletal remains suggest that in the Paleolithic woman menarche occurred at an age between 7 and 13 years, early sexual maturation being a trade-off for reduced life expectancy. In the classical, as well as in the medieval years, the age at menarche was generally reported to be at approximately 14 years, with a range from 12 to 15 years. A significant retardation of the age at menarche occurred in the beginning of the modern times, soon after the industrial revolution, due to the deterioration of the living conditions, with most studies reporting menarche to occur at 15-16 years. In the 20th century, especially in the second half of it, in the industrialized countries, the age at menarche decreased significantly, as a result of the improvement of the socioeconomic conditions, occurring at 12-13 years. In the present times, in the developed countries, this trend seems to slow down or level off.

  8. Using seafaring simulations and shortest-hop trajectories to model the prehistoric colonization of Remote Oceania.

    PubMed

    Montenegro, Álvaro; Callaghan, Richard T; Fitzpatrick, Scott M

    2016-10-24

    The prehistoric colonization of islands in Remote Oceania that began ∼3400 B.P. represents what was arguably the most expansive and ambitious maritime dispersal of humans across any of the world's seas or oceans. Though archaeological evidence has provided a relatively clear picture of when many of the major island groups were colonized, there is still considerable debate as to where these settlers originated from and their strategies/trajectories used to reach habitable land that other datasets (genetic, linguistic) are also still trying to resolve. To address these issues, we have harnessed the power of high-resolution climatic and oceanographic datasets in multiple seafaring simulation platforms to examine major pulses of colonization in the region. Our analysis, which takes into consideration currents, land distribution, wind periodicity, the influence of El Niño Southern Oscillation (ENSO) events, and "shortest-hop" trajectories, demonstrate that (i) seasonal and semiannual climatic changes were highly influential in structuring ancient Pacific voyaging; (ii) western Micronesia was likely settled from somewhere around the Maluku (Molucca) Islands; (iii) Samoa was the most probable staging area for the colonization of East Polynesia; and (iv) although there are major differences in success rates depending on time of year and the occurrence of ENSO events, settlement of Hawai'i and New Zealand is possible from the Marquesas or Society Islands, the same being the case for settlement of Easter Island from Mangareva or the Marquesas.

  9. Prehistoric land use and Neolithisation in Europe in the context of regional climate events

    NASA Astrophysics Data System (ADS)

    Lemmen, C.; Wirtz, K. W.; Gronenborn, D.

    2009-04-01

    We present a simple, adaptation-driven, spatially explicit model of pre-Bronze age socio-technological change, called the Global Land Use and Technological Evolution Simulator (GLUES). The socio-technological realm is described by three characteristic traits: available technology, subsistence style ratio, and economic diversity. Human population and culture develop in the context of global paleoclimate and regional paleoclimate events. Global paleoclimate is derived from CLIMBER-2 Earth System Model anomalies superimposed on the IIASA temperature and precipitation database. Regional a forcing is provided by abrupt climate deteriorations from a compilation of 138 long-term high-resolution climate proxy time series from mostly terrestrial and near-shore archives. The GLUES simulator provides for a novel way to explore the interplay between climate, climate change, and cultural evolution both on the Holocene timescale as well as for short-term extreme event periods. We sucessfully simulate the migration of people and the diffusion of Neolithic technology from the Near East into Europe in the period 12000-4000 a BP. We find good agreement with recent archeological compilations of Western Eurasian Neolithic sites. No causal relationship between climate events and cultural evolution could be identified, but the speed of cultural development is found to be modulated by the frequency of climate events. From the demographic evolution and regional ressource consumption, we estimate regional land use change and prehistoric greenhouse gas emissions.

  10. Chemical Analysis of Pottery Demonstrates Prehistoric Origin for High-Altitude Alpine Dairying.

    PubMed

    Carrer, Francesco; Colonese, André Carlo; Lucquin, Alexandre; Petersen Guedes, Eduardo; Thompson, Anu; Walsh, Kevin; Reitmaier, Thomas; Craig, Oliver E

    2016-01-01

    The European high Alps are internationally renowned for their dairy produce, which are of huge cultural and economic significance to the region. Although the recent history of alpine dairying has been well studied, virtually nothing is known regarding the origins of this practice. This is due to poor preservation of high altitude archaeological sites and the ephemeral nature of transhumance economic practices. Archaeologists have suggested that stone structures that appear around 3,000 years ago are associated with more intense seasonal occupation of the high Alps and perhaps the establishment of new economic strategies. Here, we report on organic residue analysis of small fragments of pottery sherds that are occasionally preserved both at these sites and earlier prehistoric rock-shelters. Based mainly on isotopic criteria, dairy lipids could only be identified on ceramics from the stone structures, which date to the Iron Age (ca. 3,000-2,500 BP), providing the earliest evidence of this practice in the high Alps. Dairy production in such a marginal environment implies a high degree of risk even by today's standards. We postulate that this practice was driven by population increase and climate deterioration that put pressure on lowland agropastoral systems and the establishment of more extensive trade networks, leading to greater demand for highly nutritious and transportable dairy products.

  11. Chemical Analysis of Pottery Demonstrates Prehistoric Origin for High-Altitude Alpine Dairying

    PubMed Central

    Carrer, Francesco; Colonese, André Carlo; Lucquin, Alexandre; Petersen Guedes, Eduardo; Thompson, Anu; Walsh, Kevin; Reitmaier, Thomas; Craig, Oliver E.

    2016-01-01

    The European high Alps are internationally renowned for their dairy produce, which are of huge cultural and economic significance to the region. Although the recent history of alpine dairying has been well studied, virtually nothing is known regarding the origins of this practice. This is due to poor preservation of high altitude archaeological sites and the ephemeral nature of transhumance economic practices. Archaeologists have suggested that stone structures that appear around 3,000 years ago are associated with more intense seasonal occupation of the high Alps and perhaps the establishment of new economic strategies. Here, we report on organic residue analysis of small fragments of pottery sherds that are occasionally preserved both at these sites and earlier prehistoric rock-shelters. Based mainly on isotopic criteria, dairy lipids could only be identified on ceramics from the stone structures, which date to the Iron Age (ca. 3,000–2,500 BP), providing the earliest evidence of this practice in the high Alps. Dairy production in such a marginal environment implies a high degree of risk even by today’s standards. We postulate that this practice was driven by population increase and climate deterioration that put pressure on lowland agropastoral systems and the establishment of more extensive trade networks, leading to greater demand for highly nutritious and transportable dairy products. PMID:27100391

  12. Specifying the differentiated contribution of farmers to groundwater depletion in two irrigated areas in North Africa

    NASA Astrophysics Data System (ADS)

    Ameur, Fatah; Amichi, Hichem; Kuper, Marcel; Hammani, Ali

    2017-09-01

    Much attention has been paid to the issue of groundwater depletion linked to intensive groundwater-based agriculture in (semi-)arid areas. Often referred to as the "overexploitation" of aquifers, groundwater depletion is generally attributed to the entire agricultural sector without distinguishing between different uses and users. Although it expresses a general concern for future users, the ambiguous term of "overexploitation" does not acknowledge the contested nature of groundwater use and emerging inequalities. Also, the impact of inequality on groundwater depletion is rarely questioned. The aim of this article is to investigate how and by whom groundwater is depleted, and in turn, how unequal access to groundwater fuels the socioeconomic differentiation of farms and groundwater depletion. Based on a detailed analysis of groundwater use from a user perspective in two irrigated areas in North Africa (Morocco and Algeria), this study shows how the context of groundwater depletion exacerbates—and is exacerbated by—existing inequalities. The paper concludes that knowing how much is withdrawn, where, and by whom provides helpful information for more informed groundwater management by a better understanding of the response of users to declining groundwater conditions and the interests and incentives of different social categories of famers to contribute to groundwater management.

  13. Specifying the differentiated contribution of farmers to groundwater depletion in two irrigated areas in North Africa

    NASA Astrophysics Data System (ADS)

    Ameur, Fatah; Amichi, Hichem; Kuper, Marcel; Hammani, Ali

    2017-04-01

    Much attention has been paid to the issue of groundwater depletion linked to intensive groundwater-based agriculture in (semi-)arid areas. Often referred to as the "overexploitation" of aquifers, groundwater depletion is generally attributed to the entire agricultural sector without distinguishing between different uses and users. Although it expresses a general concern for future users, the ambiguous term of "overexploitation" does not acknowledge the contested nature of groundwater use and emerging inequalities. Also, the impact of inequality on groundwater depletion is rarely questioned. The aim of this article is to investigate how and by whom groundwater is depleted, and in turn, how unequal access to groundwater fuels the socioeconomic differentiation of farms and groundwater depletion. Based on a detailed analysis of groundwater use from a user perspective in two irrigated areas in North Africa (Morocco and Algeria), this study shows how the context of groundwater depletion exacerbates—and is exacerbated by—existing inequalities. The paper concludes that knowing how much is withdrawn, where, and by whom provides helpful information for more informed groundwater management by a better understanding of the response of users to declining groundwater conditions and the interests and incentives of different social categories of famers to contribute to groundwater management.

  14. Depleted Argon from Underground Sources

    SciTech Connect

    Back, H. O.; Galbiati, C.; Goretti, A.; Loer, B.; Montanari, D.; Mosteiro, P.; Alexander, T.; Alton, A.; Rogers, H.; Kendziora, C.; Pordes, S.

    2011-04-27

    Argon is a strong scintillator and an ideal target for Dark Matter detection; however {sup 39}Ar contamination in atmospheric argon from cosmic ray interactions limits the size of liquid argon dark matter detectors due to pile-up. Argon from deep underground is depleted in {sup 39}Ar due to the cosmic ray shielding of the earth. In Cortez, Colorado, a CO{sub 2} well has been discovered to contain approximately 600 ppm of argon as a contamination in the CO{sub 2}. We first concentrate the argon locally to 3% in an Ar, N{sub 2}, and He mixture, from the CO{sub 2} through chromatographic gas separation, and then the N{sub 2} and He will be removed by continuous distillation to purify the argon. We have collected 26 kg of argon from the CO{sub 2} facility and a cryogenic distillation column is under construction at Fermilab to further purify the argon.

  15. Depleted uranium disposal options evaluation

    SciTech Connect

    Hertzler, T.J.; Nishimoto, D.D.; Otis, M.D.

    1994-05-01

    The Department of Energy (DOE), Office of Environmental Restoration and Waste Management, has chartered a study to evaluate alternative management strategies for depleted uranium (DU) currently stored throughout the DOE complex. Historically, DU has been maintained as a strategic resource because of uses for DU metal and potential uses for further enrichment or for uranium oxide as breeder reactor blanket fuel. This study has focused on evaluating the disposal options for DU if it were considered a waste. This report is in no way declaring these DU reserves a ``waste,`` but is intended to provide baseline data for comparison with other management options for use of DU. To PICS considered in this report include: Retrievable disposal; permanent disposal; health hazards; radiation toxicity and chemical toxicity.

  16. High-voltage-compatible, fully depleted CCDs

    SciTech Connect

    Holland, Stephen E.; Bebek, Chris J.; Dawson, Kyle S.; Emes, JohnE.; Fabricius, Max H.; Fairfield, Jessaym A.; Groom, Don E.; Karcher, A.; Kolbe, William F.; Palaio, Nick P.; Roe, Natalie A.; Wang, Guobin

    2006-05-15

    We describe charge-coupled device (CCD) developmentactivities at the Lawrence Berkeley National Laboratory (LBNL).Back-illuminated CCDs fabricated on 200-300 mu m thick, fully depleted,high-resistivity silicon substrates are produced in partnership with acommercial CCD foundry.The CCDs are fully depleted by the application ofa substrate bias voltage. Spatial resolution considerations requireoperation of thick, fully depleted CCDs at high substrate bias voltages.We have developed CCDs that are compatible with substrate bias voltagesof at least 200V. This improves spatial resolution for a given thickness,and allows for full depletion of thicker CCDs than previously considered.We have demonstrated full depletion of 650-675 mu m thick CCDs, withpotential applications in direct x-ray detection. In this work we discussthe issues related to high-voltage operation of fully depleted CCDs, aswell as experimental results on high-voltage-compatible CCDs.

  17. CO depletion in the Gould Belt clouds

    NASA Astrophysics Data System (ADS)

    Christie, H.; Viti, S.; Yates, J.; Hatchell, J.; Fuller, G. A.; Duarte-Cabral, A.; Sadavoy, S.; Buckle, J. V.; Graves, S.; Roberts, J.; Nutter, D.; Davis, C.; White, G. J.; Hogerheijde, M.; Ward-Thompson, D.; Butner, H.; Richer, J.; Di Francesco, J.

    2012-05-01

    We present a statistical comparison of CO depletion in a set of local molecular clouds within the Gould Belt using Sub-millimetre Common User Bolometer Array (SCUBA) and Heterodyne Array Receiver Programme (HARP) data. This is the most wide-ranging study of depletion thus far within the Gould Belt. We estimate CO column densities assuming local thermodynamic equilibrium and, for a selection of sources, using the radiative transfer code RADEX in order to compare the two column density estimation methods. High levels of depletion are seen in the centres of several dust cores in all the clouds. We find that in the gas surrounding protostars, levels of depletion are somewhat lower than for starless cores with the exception of a few highly depleted protostellar cores in Serpens and NGC 2024. There is a tentative correlation between core mass and core depletion, particularly in Taurus and Serpens. Taurus has, on average, the highest levels of depletion. Ophiuchus has low average levels of depletion which could perhaps be related to the anomalous dust grain size distribution observed in this cloud. High levels of depletion are often seen around the edges of regions of optical emission (Orion) or in more evolved or less dynamic regions such as the bowl of L1495 in Taurus and the north-western region of Serpens.

  18. Ego depletion increases risk-taking.

    PubMed

    Fischer, Peter; Kastenmüller, Andreas; Asal, Kathrin

    2012-01-01

    We investigated how the availability of self-control resources affects risk-taking inclinations and behaviors. We proposed that risk-taking often occurs from suboptimal decision processes and heuristic information processing (e.g., when a smoker suppresses or neglects information about the health risks of smoking). Research revealed that depleted self-regulation resources are associated with reduced intellectual performance and reduced abilities to regulate spontaneous and automatic responses (e.g., control aggressive responses in the face of frustration). The present studies transferred these ideas to the area of risk-taking. We propose that risk-taking is increased when individuals find themselves in a state of reduced cognitive self-control resources (ego-depletion). Four studies supported these ideas. In Study 1, ego-depleted participants reported higher levels of sensation seeking than non-depleted participants. In Study 2, ego-depleted participants showed higher levels of risk-tolerance in critical road traffic situations than non-depleted participants. In Study 3, we ruled out two alternative explanations for these results: neither cognitive load nor feelings of anger mediated the effect of ego-depletion on risk-taking. Finally, Study 4 clarified the underlying psychological process: ego-depleted participants feel more cognitively exhausted than non-depleted participants and thus are more willing to take risks. Discussion focuses on the theoretical and practical implications of these findings.

  19. Building and Applying "Insularity Theory": Review on Knapp's Prehistoric and Protohistoric Cyprus, 2008.

    NASA Astrophysics Data System (ADS)

    Katsarou-Tzeveleki, Stella

    Prehistoric and Protohistoric Cyprus by A. Bernard Knapp involves us in a highly creative reading. This is due mainly to the fact that the author engages in a holistic synthesis of Cyprus in the Bronze Age, not by emphasizing the events and descriptions of the material remains, but by concentrating upon the difficult question of the identity of the islanders of this period and the processes by which it was formed. The author's teaching of Mediterranean prehistory at the University of Glasgow fully accounts for his need to produce a comprehensive theoretical work of this kind: the basic questions asked by students give rise to theoretical concerns for any teacher aiming to 'distil' the essential synthesis that forms the starting point for any further detailed archaeological description. This essential answer seems to have troubled Knapp for some time, judging by the long list of his writings seeking to synthesize aspects of Cypriot economy, cult and society; the present book is thus the highly interesting outcome of the mature thinking of an experienced fieldworker as much as a theoretical archaeologist and teacher. What, then, is the essential question that Knapp seeks to answer through this book? His question focuses on the identity of the islanders of Cyprus during the 'most formative periods, from the village based culture to the international, town-centred, even state-level polity' (p. 1), the way in which this identity was formed, and how it is reflected in both any recorded event and the material culture of the island in this specific period. Moreover, he also explores more fully what the distinctive features of island identity in general are, how they are constituted and how they influence the material culture of any island population. In seeking the answers, the author avoids a number of the usual approaches to Cypriot archaeology and turns, instead, to new interpretive directions. The approaches he avoids are the citing of events of Cypriot prehistory, the

  20. Heterogeneity of Taiwan's indigenous population: possible relation to prehistoric Mongoloid dispersals.

    PubMed

    Lin, M; Chu, C C; Lee, H L; Chang, S L; Ohashi, J; Tokunaga, K; Akaza, T; Juji, T

    2000-01-01

    Taiwan's 9 indigenous tribes (Tsou, Bunun, Paiwan, Rukai, Atayal, Saisiat, Ami, Puyuma, Yami) are highly homogeneous within each tribe, but diversified among the different tribes due to long-term isolation, most probably since Taiwan became an island about 12,000 years ago. Homogeneity of each tribe is evidenced by many HLA-A,B,C alleles having the world's highest ever reported frequencies, e.g. A24 (86.3%), A26 (18.8%), Cw10 (36.8%), Cw7 (66%), Cw8 (32.1%), B13 (27.9%), B62 (37.4%), B75 (18%), B39 (53.5%), B60 (33.3%), and B48 (24%). Also, all of these tribes have HLA class I haplotype frequencies greater than 10%, with A24-Cw7-B39 in Saisiat (44.5%) being the highest, suggesting Taiwan's indigenous tribes are probably the most homogeneous ( the "purest") population in the world. A24-Cw8-B48, A24-Cw10-B60 and A24-Cw9-B61 found common to many Taiwan indigenous tribes, have also been observed in Maori, Papua New Guinea Highlanders, Orochons, Mongolians, Inuit, Japanese, Man, Buryat, Yakut, Tlingit, Tibetans and Thais. These findings suggest Taiwan's indigenous groups are more or less genetically related to both northern and southern Asians. Principal component analysis and the phylogenetic tree (using the neighbor-joining method) showed close relationship between the indigenous groups and Oceanians. This relationship supports the hypothesis that Taiwan was probably on the route of prehistoric Mongoloid dispersals that most likely took place along the coastal lowland of the Asian continent (which is under the sea today). Cultural anthropology also suggests a relationship between Taiwan's indigenous tribes and southern Asians and to a lesser extent, northern Asians. However, the indigenous groups show little genetic relationship to current southern and northern Han Chinese.

  1. Revealing the prehistoric settlement of Australia by Y chromosome and mtDNA analysis

    PubMed Central

    Hudjashov, Georgi; Kivisild, Toomas; Underhill, Peter A.; Endicott, Phillip; Sanchez, Juan J.; Lin, Alice A.; Shen, Peidong; Oefner, Peter; Renfrew, Colin; Villems, Richard; Forster, Peter

    2007-01-01

    Published and new samples of Aboriginal Australians and Melanesians were analyzed for mtDNA (n = 172) and Y variation (n = 522), and the resulting profiles were compared with the branches known so far within the global mtDNA and the Y chromosome tree. (i) All Australian lineages are confirmed to fall within the mitochondrial founder branches M and N and the Y chromosomal founders C and F, which are associated with the exodus of modern humans from Africa ≈50–70,000 years ago. The analysis reveals no evidence for any archaic maternal or paternal lineages in Australians, despite some suggestively robust features in the Australian fossil record, thus weakening the argument for continuity with any earlier Homo erectus populations in Southeast Asia. (ii) The tree of complete mtDNA sequences shows that Aboriginal Australians are most closely related to the autochthonous populations of New Guinea/Melanesia, indicating that prehistoric Australia and New Guinea were occupied initially by one and the same Palaeolithic colonization event ≈50,000 years ago, in agreement with current archaeological evidence. (iii) The deep mtDNA and Y chromosomal branching patterns between Australia and most other populations around the Indian Ocean point to a considerable isolation after the initial arrival. (iv) We detect only minor secondary gene flow into Australia, and this could have taken place before the land bridge between Australia and New Guinea was submerged ≈8,000 years ago, thus calling into question that certain significant developments in later Australian prehistory (the emergence of a backed-blade lithic industry, and the linguistic dichotomy) were externally motivated. PMID:17496137

  2. A Study on Generic Representation of Skeletal Remains Replication of Prehistoric Burial

    NASA Astrophysics Data System (ADS)

    Shao, C.-W.; Chiu, H.-L.; Chang, S.-K.

    2015-08-01

    Generic representation of skeletal remains from burials consists of three dimensions which include physical anthropologists, replication technicians, and promotional educators. For the reason that archaeological excavation is irreversible and disruptive, detail documentation and replication technologies are surely needed for many purposes. Unearthed bones during the process of 3D digital scanning need to go through reverse procedure, 3D scanning, digital model superimposition, rapid prototyping, mould making, and the integrated errors generated from the presentation of colours and textures are important issues for the presentation of replicate skeleton remains among professional decisions conducted by physical anthropologists, subjective determination of makers, and the expectations of viewers. This study presents several cases and examines current issues on display and replication technologies for human skeletal remains of prehistoric burials. This study documented detail colour changes of human skeleton over time for the reference of reproduction. The tolerance errors of quantification and required technical qualification is acquired according to the precision of 3D scanning, the specification requirement of rapid prototyping machine, and the mould making process should following the professional requirement for physical anthropological study. Additionally, the colorimeter is adopted to record and analyse the "colour change" of the human skeletal remains from wet to dry condition. Then, the "colure change" is used to evaluate the "real" surface texture and colour presentation of human skeletal remains, and to limit the artistic presentation among the human skeletal remains reproduction. The"Lingdao man No.1", is a well preserved burial of early Neolithic period (8300 B.P.) excavated from Liangdao-Daowei site, Matsu, Taiwan , as the replicating object for this study. In this study, we examined the reproduction procedures step by step for ensuring the surface

  3. Influence of cranial deformation on facial morphology among prehistoric South Central Andean populations.

    PubMed

    Rhode, Matthew P; Arriaza, Bernardo T

    2006-08-01

    Calculating biodistances among South American populations using cranial measurements is often hindered, as many available skeletal collections exhibit deformation. Acknowledging vault modifications, researchers have sought measurements in other regions which are unaffected by deformation. In the 1970s, a set of 10 "relatively" unaffected facial measurements was identified in Argentinean crania that later became the basis of numerous South American biodistance studies. These measurements include: minimum frontal breadth, bizygomatic breadth, orbit height, orbit breadth, palate breath, palate length, upper facial height, basion-prosthion length, nasal height, and nasal breadth. Palate length was excluded from the present analysis due to considerable measurement error. The suitability of these measurements in populations other than Argentineans has not been rigorously tested. Using a sample of 350 prehistoric crania from the Museo Arqueológico San Miguel de Azapa (MASMA, Arica, Chile), this project tested the hypothesis that these measurements are unaffected by either annular or tabular deformation. Results obtained from MANOVA analysis indicate this hypothesis cannot be fully supported. Among males, only 3 of the 9 measurements are unaffected by either form of deformation (palate breadth, basion-prosthion length, and nasal breadth), while analysis of females indicates that 4 of the 9 measurements remain unaltered (minimum frontal breadth, orbit breadth, basion-prosthion length, and nasal breadth). Additionally, analogous to the vault, facial measurements display patterns consistent with the deformation applied. Two implications can be drawn from this research: 1) previous studies using these measurements must be interpreted cautiously, and 2) researchers using these measurements must explicitly test their suitability in each population.

  4. Magnitude and Surface Rupture Length of Prehistoric Upper Crustal Earthquakes in the Puget Lowland, Washington State

    NASA Astrophysics Data System (ADS)

    Sherrod, B. L.; Styron, R. H.

    2016-12-01

    Paleoseismic studies documented prehistoric earthquakes after the last glaciation ended 15 ka on 13 upper-crustal fault zones in the Cascadia fore arc. These fault zones are a consequence of north-directed fore arc block migration manifesting as a series of bedrock uplifts and intervening structural basins in the southern Salish Sea lowland between Vancouver, B.C. to the north and Olympia, WA to the south, and bounded on the east and west by the Cascade Mountains and Olympic Mountains, respectively. Our dataset uses published information and includes 27 earthquakes tabulated from observations of postglacial deformation at 63 sites. Stratigraphic offsets along faults consist of two types of measurements: 1) vertical separation of strata along faults observed in fault scarp excavations, and 2) estimates from coastal uplift and subsidence. We used probabilistic methods to estimate past rupture magnitudes and surface rupture length (SRL), applying empirical observations from modern earthquakes and point measurements from paleoseismic sites (Biasi and Weldon, 2006). Estimates of paleoearthquake magnitude ranged between M 6.5 and M 7.5. SRL estimates varied between 20 and 90 km. Paleoearthquakes on the Seattle fault zone and Saddle Mountain West fault about 1100 years ago were outliers in our analysis. Large offsets observed for these two earthquakes implies a M 7.8 and 200 km SRL, given the average observed ratio of slip/SRL in modern earthquakes. The actual mapped traces of these faults are less than 200km, implying these earthquakes had an unusually high static stress drop or, in the case of the Seattle fault, splay faults may have accentuated uplift in the hanging wall. Refined calculations incorporating fault area may change these magnitude and SRL estimates. Biasi, G.P., and Weldon, R.J., 2006, Estimating Surface Rupture Length and Magnitude of Paleoearthquakes from Point Measurements of Rupture Displacement: B. Seismol. Soc. Am., 96, 1612-1623.

  5. [Dietary habits and the state of the human oral cavity in the prehistoric age].

    PubMed

    Kee, C D

    1990-06-01

    This is an age-by-age summation of literature on over 100 sites (of more than 250 excavated prehistoric ruins on the Korean Peninsula: about 160 places in South Korea--Paleolithic Age 15, Neolithic Age 21, Bronze Age 90 and Iron Age 35--and about 90 places in North Korea) which produced dietary-habit-related devices such as hunting tools, fishing instruments, farming equipments, tools of daily life, and human bones and teeth. 1) Various dietary-habit-related Old Stone-Age tools, instruments and other items were found. Among them were stone axes, stone hand axes, fish spears and hooks made of bone or horn, stone blades, stone scrapers and stone drills believed to have been used in daily life, and charcoal and sites of furnaces used for cooking. Furthermore, it was found that there were severe dental abrasions and dental caries among the inhabitants of the Korean Peninsula in the Old Stone Age. 2) Some evidences were found which lead us to believe that hunting was practiced with stone arrowheads in the New Stone Age. Stone net sinkers, which is the evidence of the use of fish nets, were also found. In addition, farming stone tools and charred cereals, both of which date back to the latter part of this period, were unearthed. Millstones, which began to be used in this age, and livestock bones were found. Where these items were discovered, 23 maxillae and mandibles with teeth and a total of 231 separate teeth of Neolithic period human beings were reported. However, there are no records indicating dental caries, but some records describe severe abrasion.

  6. Prehistoric versus modern Baltic Sea cod fisheries: selectivity across the millennia

    PubMed Central

    Limburg, Karin E; Walther, Yvonne; Hong, Bongghi; Olson, Carina; Storå, Jan

    2008-01-01

    Combining Stone Age and modern data provides unique insights for management, extending beyond contemporary problems and shifting baselines. Using fish chronometric parts, we compared demographic characteristics of exploited cod populations from the Neolithic Period (4500 BP) to the modern highly exploited fishery in the central Baltic Sea. We found that Neolithic cod were larger (mean 56.4 cm, 95% confidence interval (CI)±0.9) than modern fish (weighted mean length in catch =49.5±0.2 cm in 1995, 48.2±0.2 cm in 2003), and older (mean ages =4.7±0.11, 3.1±0.02 and 3.6±0.02 years for Neolithic, 1995, and 2003 fisheries, respectively). Fishery-independent surveys in 1995 and 2003 show that mean sizes in the stock are 16–17 cm smaller than reflected in the fishery, and mean ages approximately 1–1.5 years younger. Modelled von Bertalanffy growth and back-calculated lengths indicated that Neolithic cod grew to smaller asymptotic lengths, but were larger at younger ages, implying rapid early growth. Very small Neolithic cod were absent and large individuals were rare as in modern times. This could be owing to selective harvests, the absence of small and large fish in the area or a combination. Comparing modern and prehistoric times, fishery selection is evident, but apparently not as great as in the North Atlantic proper. PMID:18755680

  7. Pre-excavation studies of prehistoric cave sites by magnetic prospecting

    NASA Astrophysics Data System (ADS)

    Itkis., Sonia; Matskevich, Zinovii; Meshveliani, Tengiz

    2014-05-01

    Detailed magnetic survey was performed for caves study in Israel (1995-1996) within the framework of the Beit Shemesh Regional Project (Judean Shephelah). The experience accumulated in Israel we applied later (2010) in two Georgian prehistoric cave sites: Cherula and Kotias-Klde. The magnetic method is based on the contrast in magnetic properties between a target object (e.g., buried archaeological feature) and the host medium (i.e, the surrounding bedrock and soil). The feasibility of the magnetic method for cave revealing was evaluated by magnetic susceptibility (κ) measurements of surrounding soil and rocks, and archaeological features: stones making up the walls, ceramic fragments and cave fill. According to data obtained, the κ of soil within caves (cave fill) is higher than that of surrounding soil. The enhancement of cave fill κ occurs because processes associated with human habitation: repeated heating and accumulation of organic debris. Both these processes provide good conditions for the conversion of the iron oxide found within the soil to a strongly ferromagnetic form (Mullins, 1977; Maher, 1986; Dalan and Banerjee, 1998, Itkis and Eppelbaum, 1999; Itkis, 2003) The presence of highly magnetic ceramics in caves also enhances magnetic contrast between practically non-magnetic bed rock (chalk in Ramat Beit Shemesh Site (Israel) and limestone (Georgian sites) and the cave fill, increasing the potential of the magnetic method to reveal caves (Itkis, 2011). Based on magnetic survey results, an excavation revealed a cave with a large amount of well preserved pottery and finds typical of the Early Bronze Age. Both studied cave sites in Georgia were located in Chiatura region of Imeretia province. Cherula site is a karstic rockshelter with a single chamber, ca 100 sq. m. The site was briefly tested in 1970s'. The area excavated in 2010 went to the depth of 60 cm below the present day surface; the limestone bedrock was not reached. The excavation revealed

  8. Optimization in differentiable manifolds in order to determine the method of construction of prehistoric wall paintings.

    PubMed

    Arabadjis, Dimitris; Rousopoulos, Panayiotis; Papaodysseus, Constantin; Exarhos, Michalis; Panagopoulos, Michail; Papazoglou-Manioudaki, Lena

    2011-11-01

    In this paper, a general methodology is introduced for the determination of potential prototype curves used for the drawing of prehistoric wall paintings. The approach includes 1) preprocessing of the wall-paintings contours to properly partition them, according to their curvature, 2) choice of prototype curves families, 3) analysis and optimization in 4-manifold for a first estimation of the form of these prototypes, 4) clustering of the contour parts and the prototypes to determine a minimal number of potential guides, and 5) further optimization in 4-manifold, applied to each cluster separately, in order to determine the exact functional form of the potential guides, together with the corresponding drawn contour parts. The methodology introduced simultaneously deals with two problems: 1) the arbitrariness in data-points orientation and 2) the determination of one proper form for a prototype curve that optimally fits the corresponding contour data. Arbitrariness in orientation has been dealt with a novel curvature based error, while the proper forms of curve prototypes have been exhaustively determined by embedding curvature deformations of the prototypes into 4-manifolds. Application of this methodology to celebrated wall paintings excavated at Tyrins, Greece, and the Greek island of Thera manifests that it is highly probable that these wall paintings were drawn by means of geometric guides that correspond to linear spirals and hyperbolae. These geometric forms fit the drawings’ lines with an exceptionally low average error, less than 0.39 mm. Hence, the approach suggests the existence of accurate realizations of complicated geometric entities more than 1,000 years before their axiomatic formulation in the Classical Ages.

  9. Modelling prehistoric terrain Models using LiDAR-data: a geomorphological approach

    NASA Astrophysics Data System (ADS)

    Höfler, Veit; Wessollek, Christine; Karrasch, Pierre

    2015-10-01

    -genetic character and can be called a prehistoric terrain model.

  10. Timing and slip for prehistoric earthquakes on the Superstition Mountain Fault, Imperial Valley, southern California

    NASA Astrophysics Data System (ADS)

    Gurrola, Larry D.; Rockwell, Thomas K.

    1996-03-01

    Trenches excavated across the Superstition Mountain fault in the Imperial Valley, California, have exposed evidence for four prehistorical earthquakes preserved in displaced lacustrine stratigraphy associated with ancient Lake Cahuilla. The presence of shoreline peat accumulations along with abundant detrital charcoal allows for high-precision age determination of some stratigraphic units, thereby providing constraints on the timing of three of the paleoearthquakes. These three events occurred within a 480- to 820-year interval during the past 1200 years. The most recent earthquake (event 1) occurred during a fluvial phase of deposition between A.D. 1440-1637, immediately prior to the inundation of the Cahuilla basin at about A.D. 1480 and 1660. A channel margin was offset 2.2 +0.4/-0.15 m in this rupture, suggesting an earthquake with a magnitude ≥7. The penultimate event (event 2) also occurred during fluvial deposition after A.D. 1280 but before another lakestand at A.D. 1440-1640. Lateral slip could not be resolved for event 2. However, based on juxtaposition of dissimilar units and the amount of deformation produced by this event, it is presumed that this was also a large earthquake. The timing of event 3 is constrained to have occurred between about A.D. 820 and 1280. This event is represented by several fractures and small displacements that rupture up to a distinct stratigraphic level or event horizon. Slip was not resolved for this event. Finally, the timing of event 4 is very poorly constrained to between A.D. 964 and 4670 B.C. Undoubtedly, many events may have occurred during this period. Notably, the past three earthquakes occurred within a period of less than 820 years, and it has been over 350 years since the last earthquake.

  11. Holocene Mass Transport Deposits in Western Norwegian fjords and lakes revealing prehistoric earthquake history of Scandinavia

    NASA Astrophysics Data System (ADS)

    Bellwald, B.; Hjelstuen, B. O.; Sejrup, H. P.; Kuvås, J.; Stokowy, T.

    2016-12-01

    The sensitivity of fjord sediments to seismic shaking makes fjord systems appropriate study sites when extending regional earthquake catalogs back in time and when estimating recurrence rates of prehistoric earthquakes in intraplate settings. In this study we compiled evidence of 140 postglacial mass movement events and their associated mass transport deposits (MTDs) from previously analyzed and new sediment cores and high-resolution seismic profiles from 22 fjord systems and six lakes in Western Norway. Evaluation of trigger mechanisms make us infer that most of these mass movement events were initiated by regional earthquakes, and that both climate-related processes and tsunamis most likely can be excluded as trigger mechanism for most of the events. A total of 33 individual earthquakes has been identified, which most likely outbalance the historically recorded events in magnitude, thus indicating magnitudes >6. Frequency plots of MTDs suggest high seismic activity in the early Holocene (11000-9700 cal. yrs BP), followed by seismic quiescence in the mid-Holocene before a seismic reactivation took place at 4000 cal. yrs BP. Coevally-triggered MTDs at 8100 cal. yrs BP are identified in all the archives, and are correlating with the age of the offshore Storegga slide. We estimate earthquake recurrence rates of 1/80 years directly after the last deglaciation of Western Norway (12800-11600 ca. yrs BP), 1/200 years for the early Holocene and 1/300 years for the last 4000 years. Our compilation suggests that the mid-Holocene is characterized by low seismic activity, suggesting recurrence rates of 1/1300 years. Comparisons of the Western Norwegian dataset with paleoseimologic studies of other previously glaciated intraplate settings indicate that both Scandinavia and the Alps show similar trends as Western Norway, whereas Eastern Canada is not correlating with the paleoseismologic trend of this study, which could be explained by different deglaciation histories.

  12. Sustainable intensification in agricultural systems

    PubMed Central

    Pretty, Jules; Bharucha, Zareen Pervez

    2014-01-01

    Background Agricultural systems are amended ecosystems with a variety of properties. Modern agroecosystems have tended towards high through-flow systems, with energy supplied by fossil fuels directed out of the system (either deliberately for harvests or accidentally through side effects). In the coming decades, resource constraints over water, soil, biodiversity and land will affect agricultural systems. Sustainable agroecosystems are those tending to have a positive impact on natural, social and human capital, while unsustainable systems feed back to deplete these assets, leaving fewer for the future. Sustainable intensification (SI) is defined as a process or system where agricultural yields are increased without adverse environmental impact and without the conversion of additional non-agricultural land. The concept does not articulate or privilege any particular vision or method of agricultural production. Rather, it emphasizes ends rather than means, and does not pre-determine technologies, species mix or particular design components. The combination of the terms ‘sustainable’ and ‘intensification’ is an attempt to indicate that desirable outcomes around both more food and improved environmental goods and services could be achieved by a variety of means. Nonetheless, it remains controversial to some. Scope and Conclusions This review analyses recent evidence of the impacts of SI in both developing and industrialized countries, and demonstrates that both yield and natural capital dividends can occur. The review begins with analysis of the emergence of combined agricultural–environmental systems, the environmental and social outcomes of recent agricultural revolutions, and analyses the challenges for food production this century as populations grow and consumption patterns change. Emergent criticisms are highlighted, and the positive impacts of SI on food outputs and renewable capital assets detailed. It concludes with observations on policies and

  13. Depletion Mapping and Constrained Optimization to Support Managing Groundwater Extraction.

    PubMed

    Fienen, Michael N; Bradbury, Kenneth R; Kniffin, Maribeth; Barlow, Paul M

    2017-06-06

    Groundwater models often serve as management tools to evaluate competing water uses including ecosystems, irrigated agriculture, industry, municipal supply, and others. Depletion potential mapping-showing the model-calculated potential impacts that wells have on stream baseflow-can form the basis for multiple potential management approaches in an oversubscribed basin. Specific management approaches can include scenarios proposed by stakeholders, systematic changes in well pumping based on depletion potential, and formal constrained optimization, which can be used to quantify the tradeoff between water use and stream baseflow. Variables such as the maximum amount of reduction allowed in each well and various groupings of wells using, for example, K-means clustering considering spatial proximity and depletion potential are considered. These approaches provide a potential starting point and guidance for resource managers and stakeholders to make decisions about groundwater management in a basin, spreading responsibility in different ways. We illustrate these approaches in the Little Plover River basin in central Wisconsin, United States-home to a rich agricultural tradition, with farmland and urban areas both in close proximity to a groundwater-dependent trout stream. Groundwater withdrawals have reduced baseflow supplying the Little Plover River below a legally established minimum. The techniques in this work were developed in response to engaged stakeholders with various interests and goals for the basin. They sought to develop a collaborative management plan at a watershed scale that restores the flow rate in the river in a manner that incorporates principles of shared governance and results in effective and minimally disruptive changes in groundwater extraction practices. © 2017, National Ground Water Association.

  14. Depletion mapping and constrained optimization to support managing groundwater extraction

    USGS Publications Warehouse

    Fienen, Michael N.; Bradbury, Kenneth R.; Kniffin, Maribeth; Barlow, Paul M.

    2017-01-01

    Groundwater models often serve as management tools to evaluate competing water uses including ecosystems, irrigated agriculture, industry, municipal supply, and others. Depletion potential mapping—showing the model-calculated potential impacts that wells have on stream baseflow - can form the basis for multiple potential management approaches in an oversubscribed basin. Specific management approaches can include scenarios proposed by stakeholders, systematic changes in well pumping based on depletion potential, and formal constrained optimization, which can be used to quantify the tradeoff between water use and stream baseflow. Variables such as the maximum amount of reduction allowed in each well and various groupings of wells using, for example, K-means clustering considering spatial proximity and depletion potential are considered. These approaches provide a potential starting point and guidance for resource managers and stakeholders to make decisions about groundwater management in a basin, spreading responsibility in different ways. We illustrate these approaches in the Little Plover River basin in central Wisconsin, United States—home to a rich agricultural tradition, with farmland and urban areas both in close proximity to a groundwater-dependent trout stream. Groundwater withdrawals have reduced baseflow supplying the Little Plover River below a legally established minimum. The techniques in this work were developed in response to engaged stakeholders with various interests and goals for the basin. They sought to develop a collaborative management plan at a watershed scale that restores the flow rate in the river in a manner that incorporates principles of shared governance and results in effective and minimally disruptive changes in groundwater extraction practices.

  15. Beneficial Uses of Depleted Uranium

    SciTech Connect

    Brown, C.; Croff, A.G.; Haire, M. J.

    1997-08-01

    Naturally occurring uranium contains 0.71 wt% {sup 235}U. In order for the uranium to be useful in most fission reactors, it must be enriched the concentration of the fissile isotope {sup 235}U must be increased. Depleted uranium (DU) is a co-product of the processing of natural uranium to produce enriched uranium, and DU has a {sup 235}U concentration of less than 0.71 wt%. In the United States, essentially all of the DU inventory is in the chemical form of uranium hexafluoride (UF{sub 6}) and is stored in large cylinders above ground. If this co-product material were to be declared surplus, converted to a stable oxide form, and disposed, the costs are estimated to be several billion dollars. Only small amounts of DU have at this time been beneficially reused. The U.S. Department of Energy (DOE) has begun the Beneficial Uses of DU Project to identify large-scale uses of DU and encourage its reuse for the primary purpose of potentially reducing the cost and expediting the disposition of the DU inventory. This paper discusses the inventory of DU and its rate of increase; DU disposition options; beneficial use options; a preliminary cost analysis; and major technical, institutional, and regulatory issues to be resolved.

  16. Depleted argon from underground sources

    SciTech Connect

    Back, H.O.; Alton, A.; Calaprice, F.; Galbiati, C.; Goretti, A.; Kendziora, C.; Loer, B.; Montanari, D.; Mosteiro, P.; Pordes, S.; /Fermilab

    2011-09-01

    Argon is a powerful scintillator and an excellent medium for detection of ionization. Its high discrimination power against minimum ionization tracks, in favor of selection of nuclear recoils, makes it an attractive medium for direct detection of WIMP dark matter. However, cosmogenic {sup 39}Ar contamination in atmospheric argon limits the size of liquid argon dark matter detectors due to pile-up. The cosmic ray shielding by the earth means that Argon from deep underground is depleted in {sup 39}Ar. In Cortez Colorado a CO{sub 2} well has been discovered to contain approximately 500ppm of argon as a contamination in the CO{sub 2}. In order to produce argon for dark matter detectors we first concentrate the argon locally to 3-5% in an Ar, N{sub 2}, and He mixture, from the CO{sub 2} through chromatographic gas separation. The N{sub 2} and He will be removed by continuous cryogenic distillation in the Cryogenic Distillation Column recently built at Fermilab. In this talk we will discuss the entire extraction and purification process; with emphasis on the recent commissioning and initial performance of the cryogenic distillation column purification.

  17. The occurrence of lead in Antarctic recent snow, firn deposited over the last two centuries and prehistoric ice

    NASA Astrophysics Data System (ADS)

    Boutron, Claude F.; Patterson, Clair C.

    1983-08-01

    Concentrations of lead have been measured by ultraclean Isotope Dilution Mass Spectrometry in snow cores covering the last two centuries collected at an inland site in East Antarctica using an ultra clean all plastic hand operated auger and in a prehistoric blue ice block collected at an Antarctic coastal site. Lead contamination of 16 to 200 pg Pb/g existed on the outside of the snow cores, but the measured concentrations decreased more or less abruptly along a radius from the outside to the centers of the snow cores, establishing interior values in the 1 to 5 pg Pb/g range. Some of these interior values are however possibly still slightly affected by lead contamination which could have intruded to the center of the cores because of slight melting of some of the snow cores before laboratory analysis. The interior of the blue ice block appears not to have been significantly contaminated, and contains about 1.7 pg Pb/g. These new data show that most previously published data on lead in Antarctic snow and ice were in high positive error because of contamination during field sampling, laboratory analysis or both. They show that lead concentrations could not have increased in Antarctic snows or ice from prehistoric times to present more than 2 to 3 fold, confirming that the remote polar areas of the Southern Hemisphere are still little affected by industrial lead pollution. Prehistoric Antarctic ice is shown to contain about 1 pg Pb/g natural excess lead above silicate dust lead; this excess cannot be entirely accounted for by volcanoes or sea spray, which suggests the possible existence of some other unknown natural source of prehistoric excess lead. Present day mean eolian fallout flux of lead in Antarctica is estimated to be about 0.07 ng Pb cm -2 yr -1, which stands in about the same proportion to that in the South Pacific Westerlies (about 1:30) as the flux in Greenland is observed to stand to those in the North Pacific and North Atlantic Westerlies.

  18. Bone trace element pattern in an 18th century population sample of Tenerife (Canary Islands): comparison with a prehistoric one.

    PubMed

    Arnay-de-la-Rosa, M; Gonzalez-Reimers, E; Velasco-Vazquez, J; Barros-Lopez, N; Galindo-Martin, L

    1998-10-01

    We have determined bone strontium (Sr), barium (Ba), calcium (Ca), and zinc (Zn) content in 24 samples belonging to adult individuals who died toward the end of the 18th century and were interred in a church's floor on the island of Tenerife, comparing the results with those obtained in 14 prehistoric samples of the same island and also with those of 7 modern controls. No differences were observed between the two ancient groups, which showed higher bone strontium and barium than the modern sample, and a slightly lower Ba/Sr ratio, thus pointing to consumption of marine sources.

  19. Depleted uranium--the growing concern.

    PubMed

    Abu-Qare, Aqel W; Abou-Donia, Mohamed B

    2002-01-01

    Recently, several studies have reported on the health and environmental consequences of the use of depleted uranium. Depleted uranium is a heavy metal that is also radioactive. It is commonly used in missiles as a counterweight because of its very high density (1.6 times more than lead). Immediate health risks associated with exposure to depleted uranium include kidney and respiratory problems, with conditions such as kidney stones, chronic cough and severe dermatitis. Long-term risks include lung and bone cancer. Several published reports implicated exposure to depleted uranium in kidney damage, mutagenicity, cancer, inhibition of bone, neurological deficits, significant decrease in the pregnancy rate in mice and adverse effects on the reproductive and central nervous systems. Acute poisoning with depleted uranium elicited renal failure that could lead to death. The environmental consequences of its residue will be felt for thousands of years. It is inhaled and passed through the skin and eyes, transferred through the placenta into the fetus, distributed into tissues and eliminated in urine. The use of depleted uranium during the Gulf and Kosovo Wars and the crash of a Boeing airplane carrying depleted uranium in Amsterdam in 1992 were implicated in a health concern related to exposure to depleted uranium.

  20. High homocysteine induces betaine depletion.

    PubMed

    Imbard, Apolline; Benoist, Jean-François; Esse, Ruben; Gupta, Sapna; Lebon, Sophie; de Vriese, An S; de Baulny, Helene Ogier; Kruger, Warren; Schiff, Manuel; Blom, Henk J

    2015-04-28

    Betaine is the substrate of the liver- and kidney-specific betaine-homocysteine (Hcy) methyltransferase (BHMT), an alternate pathway for Hcy remethylation. We hypothesized that BHMT is a major pathway for homocysteine removal in cases of hyperhomocysteinaemia (HHcy). Therefore, we measured betaine in plasma and tissues from patients and animal models of HHcy of genetic and acquired cause. Plasma was collected from patients presenting HHcy without any Hcy interfering treatment. Plasma and tissues were collected from rat models of HHcy induced by diet and from a mouse model of cystathionine β-synthase (CBS) deficiency. S-adenosyl-methionine (AdoMet), S-adenosyl-homocysteine (AdoHcy), methionine, betaine and dimethylglycine (DMG) were quantified by ESI-LC-MS/MS. mRNA expression was quantified using quantitative real-time (QRT)-PCR. For all patients with diverse causes of HHcy, plasma betaine concentrations were below the normal values of our laboratory. In the diet-induced HHcy rat model, betaine was decreased in all tissues analysed (liver, brain, heart). In the mouse CBS deficiency model, betaine was decreased in plasma, liver, heart and brain, but was conserved in kidney. Surprisingly, BHMT expression and activity was decreased in liver. However, in kidney, BHMT and SLC6A12 expression was increased in CBS-deficient mice. Chronic HHcy, irrespective of its cause, induces betaine depletion in plasma and tissues (liver, brain and heart), indicating a global decrease in the body betaine pool. In kidney, betaine concentrations were not affected, possibly due to overexpression of the betaine transporter SLC6A12 where betaine may be conserved because of its crucial role as an osmolyte.

  1. High homocysteine induces betaine depletion

    PubMed Central

    Imbard, Apolline; Benoist, Jean-François; Esse, Ruben; Gupta, Sapna; Lebon, Sophie; de Vriese, An S; de Baulny, Helene Ogier; Kruger, Warren; Schiff, Manuel; Blom, Henk J.

    2015-01-01

    Betaine is the substrate of the liver- and kidney-specific betaine-homocysteine (Hcy) methyltransferase (BHMT), an alternate pathway for Hcy remethylation. We hypothesized that BHMT is a major pathway for homocysteine removal in cases of hyperhomocysteinaemia (HHcy). Therefore, we measured betaine in plasma and tissues from patients and animal models of HHcy of genetic and acquired cause. Plasma was collected from patients presenting HHcy without any Hcy interfering treatment. Plasma and tissues were collected from rat models of HHcy induced by diet and from a mouse model of cystathionine β-synthase (CBS) deficiency. S-adenosyl-methionine (AdoMet), S-adenosyl-homocysteine (AdoHcy), methionine, betaine and dimethylglycine (DMG) were quantified by ESI—LC–MS/MS. mRNA expression was quantified using quantitative real-time (QRT)-PCR. For all patients with diverse causes of HHcy, plasma betaine concentrations were below the normal values of our laboratory. In the diet-induced HHcy rat model, betaine was decreased in all tissues analysed (liver, brain, heart). In the mouse CBS deficiency model, betaine was decreased in plasma, liver, heart and brain, but was conserved in kidney. Surprisingly, BHMT expression and activity was decreased in liver. However, in kidney, BHMT and SLC6A12 expression was increased in CBS-deficient mice. Chronic HHcy, irrespective of its cause, induces betaine depletion in plasma and tissues (liver, brain and heart), indicating a global decrease in the body betaine pool. In kidney, betaine concentrations were not affected, possibly due to overexpression of the betaine transporter SLC6A12 where betaine may be conserved because of its crucial role as an osmolyte. PMID:26182429

  2. Gulf war depleted uranium risks.

    PubMed

    Marshall, Albert C

    2008-01-01

    US and British forces used depleted uranium (DU) in armor-piercing rounds to disable enemy tanks during the Gulf and Balkan Wars. Uranium particulate is generated by DU shell impact and particulate entrained in air may be inhaled or ingested by troops and nearby civilian populations. As uranium is slightly radioactive and chemically toxic, a number of critics have asserted that DU exposure has resulted in a variety of adverse health effects for exposed veterans and nearby civilian populations. The study described in this paper used mathematical modeling to estimate health risks from exposure to DU during the 1991 Gulf War for both US troops and nearby Iraqi civilians. The analysis found that the risks of DU-induced leukemia or birth defects are far too small to result in an observable increase in these health effects among exposed veterans or Iraqi civilians. The analysis indicated that only a few ( approximately 5) US veterans in vehicles accidentally targeted by US tanks received significant exposure levels, resulting in about a 1.4% lifetime risk of DU radiation-induced fatal cancer (compared with about a 24% risk of a fatal cancer from all other causes). These veterans may have also experienced temporary kidney damage. Iraqi children playing for 500 h in DU-destroyed vehicles are predicted to incur a cancer risk of about 0.4%. In vitro and animal tests suggest the possibility of chemically induced health effects from DU internalization, such as immune system impairment. Further study is needed to determine the applicability of these findings for Gulf War exposure to DU. Veterans and civilians who did not occupy DU-contaminated vehicles are unlikely to have internalized quantities of DU significantly in excess of normal internalization of natural uranium from the environment.

  3. Specification for the VERA Depletion Benchmark Suite

    SciTech Connect

    Kim, Kang Seog

    2015-12-17

    CASL-X-2015-1014-000 iii Consortium for Advanced Simulation of LWRs EXECUTIVE SUMMARY The CASL neutronics simulator MPACT is under development for the neutronics and T-H coupled simulation for the pressurized water reactor. MPACT includes the ORIGEN-API and internal depletion module to perform depletion calculations based upon neutron-material reaction and radioactive decay. It is a challenge to validate the depletion capability because of the insufficient measured data. One of the detoured methods to validate it is to perform a code-to-code comparison for benchmark problems. In this study a depletion benchmark suite has been developed and a detailed guideline has been provided to obtain meaningful computational outcomes which can be used in the validation of the MPACT depletion capability.

  4. Action orientation overcomes the ego depletion effect.

    PubMed

    Dang, Junhua; Xiao, Shanshan; Shi, Yucai; Mao, Lihua

    2015-04-01

    It has been consistently demonstrated that initial exertion of self-control had negative influence on people's performance on subsequent self-control tasks. This phenomenon is referred to as the ego depletion effect. Based on action control theory, the current research investigated whether the ego depletion effect could be moderated by individuals' action versus state orientation. Our results showed that only state-oriented individuals exhibited ego depletion. For individuals with action orientation, however, their performance was not influenced by initial exertion of self-control. The beneficial effect of action orientation against ego depletion in our experiment results from its facilitation for adapting to the depleting task. © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  5. Violence in the prehistoric period of Japan: the spatio-temporal pattern of skeletal evidence for violence in the Jomon period.

    PubMed

    Nakao, Hisashi; Tamura, Kohei; Arimatsu, Yui; Nakagawa, Tomomi; Matsumoto, Naoko; Matsugi, Takehiko

    2016-03-01

    Whether man is predisposed to lethal violence, ranging from homicide to warfare, and how that may have impacted human evolution, are among the most controversial topics of debate on human evolution. Although recent studies on the evolution of warfare have been based on various archaeological and ethnographic data, they have reported mixed results: it is unclear whether or not warfare among prehistoric hunter-gatherers was common enough to be a component of human nature and a selective pressure for the evolution of human behaviour. This paper reports the mortality attributable to violence, and the spatio-temporal pattern of violence thus shown among ancient hunter-gatherers using skeletal evidence in prehistoric Japan (the Jomon period: 13 000 cal BC-800 cal BC). Our results suggest that the mortality due to violence was low and spatio-temporally highly restricted in the Jomon period, which implies that violence including warfare in prehistoric Japan was not common.

  6. Violence in the prehistoric period of Japan: the spatio-temporal pattern of skeletal evidence for violence in the Jomon period

    PubMed Central

    Nakao, Hisashi; Tamura, Kohei; Arimatsu, Yui; Nakagawa, Tomomi; Matsumoto, Naoko; Matsugi, Takehiko

    2016-01-01

    Whether man is predisposed to lethal violence, ranging from homicide to warfare, and how that may have impacted human evolution, are among the most controversial topics of debate on human evolution. Although recent studies on the evolution of warfare have been based on various archaeological and ethnographic data, they have reported mixed results: it is unclear whether or not warfare among prehistoric hunter–gatherers was common enough to be a component of human nature and a selective pressure for the evolution of human behaviour. This paper reports the mortality attributable to violence, and the spatio-temporal pattern of violence thus shown among ancient hunter–gatherers using skeletal evidence in prehistoric Japan (the Jomon period: 13 000 cal BC–800 cal BC). Our results suggest that the mortality due to violence was low and spatio-temporally highly restricted in the Jomon period, which implies that violence including warfare in prehistoric Japan was not common. PMID:27029838

  7. Vertical stability of mercury in historic and prehistoric sediments from Clear Lake, California.

    PubMed

    Suchanek, Thomas H; Richerson, Peter J; Zierenberg, Robert A; Slotton, Darell G; Mullen, Lauri H

    2008-12-01

    Clear Lake, California, USA, is the site of the Sulphur Bank Mercury Mine, now a U.S. Environmental Protection Agency Superfund Site. Intermittent mining from 1873 to 1957 resulted in approximately 100 Mg of mercury (Hg) being deposited into the lake's ecosystem. Sediment cores to approximately 2.5 m depth (dated using 210Pb and 14C) represent approximately 3000 years of sedimentation. Clear Lake sediments have experienced Hg deposition from anthropogenic sources (mining) during historic times (to the mid-1900s) and geologic sources during prehistoric times (prior to the mid-1800s). This provides a unique opportunity to evaluate hypotheses relating to (1) the influence of the mine on Hg loading to the lake and (2) the potential upward mobilization of Hg by diagenetic processes proposed by some as an alternative explanation for increased Hg concentrations at the surface of the sediment column believed to be caused by increased global atmospheric deposition. Although Hg mining began in 1873, no significant evidence of anthropogenic Hg loading was detected in cores prior to open-pit mining ca. 1927, which also involved bulldozing mine waste rock and tailings into the lake. Exponential increases in total Hg (TotHg) and methylmercury (MeHg) were observed above the 1927 horizon, where estimated sedimentation rates were 2.2-20.4 mm/yr and peaks of both forms of Hg maintained vertical stability within the sediment column. Below the 1927 horizon, a slow increase in both TotHg and MeHg with depth was observed from approximately 1000 to 3000 years before present, where sedimentation rates ranged from approximately 0.6 to 2.0 mm/yr and elevated Hg profiles appear stable. Vertical stability of Hg in the shallow and deep sediment column suggests that both TotHg and MeHg do not undergo diagenetic upward mobilization within the sediment column under rapid or slow sedimentation rates. Because (1) these data were collected at a site with known anthropogenic and geologic sources and

  8. Berber genealogy and the politics of prehistoric archaeology and craniology in French Algeria (1860s-1880s).

    PubMed

    Effros, Bonnie

    2017-03-01

    Following the conquest of Algiers and its surrounding territory by the French army in 1830, officers noted an abundance of standing stones in this region of North Africa. Although they attracted considerably less attention among their cohort than more familiar Roman monuments such as triumphal arches and bridges, these prehistoric remains were similar to formations found in Brittany and other parts of France. The first effort to document these remains occurred in 1863, when Laurent-Charles Féraud, a French army interpreter, recorded thousands of dolmens and stone formations south-west of Constantine. Alleging that these constructions were Gallic, Féraud hypothesized the close affinity of the French, who claimed descent from the ancient Gauls, with the early inhabitants of North Africa. After Féraud's claims met with scepticism among many prehistorians, French scholars argued that these remains were constructed by the ancestors of the Berbers (Kabyles in contemporary parlance), whom they hypothesized had been dominated by a blond race of European origin. Using craniometric statistics of human remains found in the vicinity of the standing stones to propose a genealogy of the Kabyles, French administrators in Algeria thereafter suggested that their mixed origins allowed them to adapt more easily than the Arab population to French colonial governance. This case study at the intersection of prehistoric archaeology, ancient history and craniology exposes how genealogical (and racial) classification made signal contributions to French colonial ideology and policy between the 1860s and 1880s.

  9. Evidence for surface rupture in 1868 on the Hayward fault in north Oakland and major rupturing in prehistoric earthquakes

    USGS Publications Warehouse

    Lienkaemper, J.J.; Williams, P.L.

    1999-01-01

    WGCEP90 estimated the Hayward fault to have a high probability (0.45 in 30 yr) of producing a future M7 Bay Area earthquake. This was based on a generic recurrence time and an unverified segmentation model, because there were few direct observations for the southern fault and none for the northern Hayward fault. To better constrain recurrence and segmentation of the northern Hayward fault, we trenched in north Oakland. Unexpectedly, we observed evidence of surface rupture probably from the M7 1868 earthquake. This extends the limit of that surface rupture 13 km north of the segmentation boundary used in the WGCEP90 model and forces serious re-evaluation of the current two-segment paradigm. Although we found that major prehistoric ruptures have occurred here, we could not radiocarbon date them. However, the last major prehistoric event appears correlative with a recently recognized event 13 km to the north dated AD 1640-1776. Copyright 1999 by the American Geophysical Union.

  10. Vocational Agriculture Handbook for Agriculture Cooperative Training.

    ERIC Educational Resources Information Center

    Texas A and M Univ., College Station. Vocational Instructional Services.

    This handbook was designed to assist school administrators, vocational administrators, vocational agricultural teachers, and area consultants of vocational agriculture in developing, implementing, and improving an agricultural cooperative training program (especially in Texas). The handbook, which presents information in a narrative format,…

  11. Agricultural Adaptation to Climate Change

    NASA Astrophysics Data System (ADS)

    Tam, A.; Jain, M.

    2016-12-01

    This research includes two projects pertaining to agricultural systems' adaption to climate change. The first research project focuses on the wheat yielding regions of India. Wheat is a major staple crop and many rural households and smallholder farmers rely on crop yields for survival. We examine the impacts of weather variability and groundwater depletion on agricultural systems, using geospatial analysis and satellite-based analysis and household-based and census data sets. We use these methods to estimate the crop yields and identify what factors are associated with low versus high yielding regions. This can help identify strategies that should be further promoted to increase crop yields. The second research project is a literature review. We conduct a meta-analysis and synthetic review on literature about agricultural adaptation to climate change. We sort through numerous articles to identify and examine articles that associate socio-economic, biophysical, and perceptional factors to farmers' adaption to climate change. Our preliminary results show that researchers tend to associate few factors to a farmers' vulnerability and adaptive capacity, and most of the research conducted is concentrated in North America, whereas tropical regions that are highly vulnerable to weather variability are underrepresented by literature. There are no conclusive results in both research projects as of so far.

  12. Agricultural SWOT analysis and wisdom agriculture design of chengdu

    NASA Astrophysics Data System (ADS)

    Zhang, Qian; Chen, Xiangyu; Du, Shaoming; Yin, Guowei; Yu, Feng; Liu, Guicai; Gong, Jin; Han, Fujun

    2017-08-01

    According to the status of agricultural information, this paper analyzed the advantages, opportunities and challenges of developing wisdom agriculture in Chengdu. By analyzed the local characteristics of Chengdu agriculture, the construction program of Chengdu wisdom agriculture was designed, which was based on the existing agricultural informatization. The positioning and development theme of Chengdu agriculture is leisure agriculture, urban agriculture and quality agriculture.

  13. Possible ozone depletions following nuclear explosions

    NASA Technical Reports Server (NTRS)

    Whitten, R. C.; Borucki, W. J.; Turco, R. P.

    1975-01-01

    The degree of depletion of the ozone layer ensuing after delivery of strategic nuclear warheads (5000 and 10,000 Mton) due to production of nitrogen oxides is theoretically assessed. Strong depletions are calculated for 16-km and 26-km altitudes, peaking 1-2 months after detonation and lasting for three years, while a significant depletion at 36 km would peak after one year. Assuming the explosions occur between 30 and 70 deg N, these effects should be much more pronounced in this region than over the Northern Hemisphere as a whole. It is concluded that Hampson's concern on this matter (1974) is well-founded.-

  14. Fully Depleted Charge-Coupled Devices

    SciTech Connect

    Holland, Stephen E.

    2006-05-15

    We have developed fully depleted, back-illuminated CCDs thatbuild upon earlier research and development efforts directed towardstechnology development of silicon-strip detectors used inhigh-energy-physics experiments. The CCDs are fabricated on the same typeof high-resistivity, float-zone-refined silicon that is used for stripdetectors. The use of high-resistivity substrates allows for thickdepletion regions, on the order of 200-300 um, with corresponding highdetection efficiency for near-infrared andsoft x-ray photons. We comparethe fully depleted CCD to thep-i-n diode upon which it is based, anddescribe the use of fully depleted CCDs in astronomical and x-ray imagingapplications.

  15. Possible ozone depletions following nuclear explosions

    NASA Technical Reports Server (NTRS)

    Whitten, R. C.; Borucki, W. J.; Turco, R. P.

    1975-01-01

    The degree of depletion of the ozone layer ensuing after delivery of strategic nuclear warheads (5000 and 10,000 Mton) due to production of nitrogen oxides is theoretically assessed. Strong depletions are calculated for 16-km and 26-km altitudes, peaking 1-2 months after detonation and lasting for three years, while a significant depletion at 36 km would peak after one year. Assuming the explosions occur between 30 and 70 deg N, these effects should be much more pronounced in this region than over the Northern Hemisphere as a whole. It is concluded that Hampson's concern on this matter (1974) is well-founded.-

  16. Agricultural Research Service

    MedlinePlus

    ... Protection Natural Resources and Sustainable Agricultural Systems Nutrition, Food Safety, and Quality Overseas Biological Control Laboratories Office of International Research Programs National Agricultural Library Research Locations (Map) ...

  17. A definition of depletion of fish stocks

    USGS Publications Warehouse

    Van Oosten, John

    1949-01-01

    Attention was focused on the need of a common and better understanding of the term depletion as applied to the fisheries in order to eliminate if possible the existing inexactness of thought on the subject. Depletion has been confused at various times with at least ten different ideas associated with it but which, as has has heen pointed out, are not synonymous at all. In defining depletion we must recognize that the term represents a condition and must not he confounded with the cause (overfishing) that leads to this condition or with the symptoms that identify it. Depletion was defined as a reduction, through overfishing, in the level of abundance of the exploitable segment of a stock that prevents the realization of the maximum productive capacity.

  18. [Hepatomioneuropathy secondary to mitochondrial DNA depletion].

    PubMed

    Blanco-Barca, M O; Gómez-Lado, C; Campos-González, Y; Castro-Gago, M

    2007-04-01

    Mitochondrial DNA depletion (mtDNA) is an highly heterogeneous condition characterized by a decreased number of mtDNA copies. The patient is a 22-month-old girl with generalized hypotonia, marked weakness, respiratory failure, arterial hypertension, hyperlactacidemia, hepatosplenomegaly and mild hypertransaminasemia without hepatic failure neither hypoketotic hypoglycemia. Electromyographic findings were consistent with neuromyopathy and muscle biopsy suggested a neurogenic atrophy. Electron microscopy revealed lipid droplets, subsarcolemmal accumulation of mitochondrias and glycogen granules. Respiratory chain enzime activities were normal. Genetic study in muscle showed mtDNA depletion, and the diagnosis of spinal muscular atrophy caused by survival motoneuron gene deletion was excluded. This case might be a novel phenotype of mtDNA depletion which could be named hepatomioneuropatyc form. A normal result of respiratory chain enzimes in muscle doesn't excluded mtDNA depletion.

  19. Polar stratospheric clouds and ozone depletion

    NASA Technical Reports Server (NTRS)

    Toon, Owen B.; Turco, Richard P.

    1991-01-01

    A review is presented of investigations into the correlation between the depletion of ozone and the formation of polar stratospheric clouds (PSCs). Satellite measurements from Nimbus 7 showed that over the years the depletion from austral spring to austral spring has generally worsened. Approximately 70 percent of the ozone above Antarctica, which equals about 3 percent of the earth's ozone, is lost during September and October. Various hypotheses for ozone depletion are discussed including the theory suggesting that chlorine compounds might be responsible for the ozone hole, whereby chlorine enters the atmosphere as a component of chlorofluorocarbons produced by humans. The three types of PSCs, nitric acid trihydrate, slowly cooling water-ice, and rapidly cooling water-ice clouds act as important components of the Antarctic ozone depletion. It is indicated that destruction of the ozone will be more severe each year for the next few decades, leading to a doubling in area of the Antarctic ozone hole.

  20. Polar stratospheric clouds and ozone depletion

    NASA Technical Reports Server (NTRS)

    Toon, Owen B.; Turco, Richard P.

    1991-01-01

    A review is presented of investigations into the correlation between the depletion of ozone and the formation of polar stratospheric clouds (PSCs). Satellite measurements from Nimbus 7 showed that over the years the depletion from austral spring to austral spring has generally worsened. Approximately 70 percent of the ozone above Antarctica, which equals about 3 percent of the earth's ozone, is lost during September and October. Various hypotheses for ozone depletion are discussed including the theory suggesting that chlorine compounds might be responsible for the ozone hole, whereby chlorine enters the atmosphere as a component of chlorofluorocarbons produced by humans. The three types of PSCs, nitric acid trihydrate, slowly cooling water-ice, and rapidly cooling water-ice clouds act as important components of the Antarctic ozone depletion. It is indicated that destruction of the ozone will be more severe each year for the next few decades, leading to a doubling in area of the Antarctic ozone hole.

  1. Sustainable intensification in agricultural systems.

    PubMed

    Pretty, Jules; Bharucha, Zareen Pervez

    2014-12-01

    Agricultural systems are amended ecosystems with a variety of properties. Modern agroecosystems have tended towards high through-flow systems, with energy supplied by fossil fuels directed out of the system (either deliberately for harvests or accidentally through side effects). In the coming decades, resource constraints over water, soil, biodiversity and land will affect agricultural systems. Sustainable agroecosystems are those tending to have a positive impact on natural, social and human capital, while unsustainable systems feed back to deplete these assets, leaving fewer for the future. Sustainable intensification (SI) is defined as a process or system where agricultural yields are increased without adverse environmental impact and without the conversion of additional non-agricultural land. The concept does not articulate or privilege any particular vision or method of agricultural production. Rather, it emphasizes ends rather than means, and does not pre-determine technologies, species mix or particular design components. The combination of the terms 'sustainable' and 'intensification' is an attempt to indicate that desirable outcomes around both more food and improved environmental goods and services could be achieved by a variety of means. Nonetheless, it remains controversial to some. This review analyses recent evidence of the impacts of SI in both developing and industrialized countries, and demonstrates that both yield and natural capital dividends can occur. The review begins with analysis of the emergence of combined agricultural-environmental systems, the environmental and social outcomes of recent agricultural revolutions, and analyses the challenges for food production this century as populations grow and consumption patterns change. Emergent criticisms are highlighted, and the positive impacts of SI on food outputs and renewable capital assets detailed. It concludes with observations on policies and incentives necessary for the wider adoption of

  2. Changes in Continental Water Storage Caused by Groundwater Depletion Since 1900

    NASA Astrophysics Data System (ADS)

    Konikow, L. F.

    2011-12-01

    Development of groundwater resources for agricultural, industrial, and municipal purposes greatly expanded in the last century, and economic gains from groundwater use have been dramatic. In many places, however, groundwater reserves have been depleted to the extent that water levels have declined tens to hundreds of meters, well yields have decreased, and pumping costs have increased. These impacts tend to reduce the efficiency and sustainability of groundwater development. Much groundwater pumped from confined aquifers is derived from storage losses in adjacent low-permeability confining layers. Depletion in confining layers is difficult to estimate and rarely monitored, but it can greatly exceed the depletion from the confined aquifer itself and groundwater drainage from confining layers is partly irreversible. For example, in the confined Dakota Aquifer, about 98 percent of the water removed from storage was derived from depletion in adjacent confining units. If cumulative long-term regional and global groundwater depletion is large, it will represent a substantial net transfer of water mass from land to the oceans, thereby contributing to sea-level rise. A U.S. national groundwater depletion census was made primarily using direct volumetric approaches; results indicate that about 800 km3 of water was depleted from groundwater systems in the U.S. during the 20th century-equivalent to a sea-level rise of approximately 2.2 mm-and 1,000 km3 through 2008. Cumulative global groundwater depletion since 1900 totals about 3,400 km3 through 2000 and 4,500 km3 through 2008 (equivalent to a sea-level rise of 12.6 mm). The rate of annual depletion has increased markedly since about 1950, with maximum rates occurring during the most recent period (2000-2008), when they averaged about 145 km3/yr (equivalent to 0.40 mm/yr of sea-level rise, or 13% of the reported rate of 3.1 mm/yr during this recent period). Overall, the volume and rate of estimated long-term global

  3. Dental calculus reveals unique insights into food items, cooking and plant processing in prehistoric central Sudan.

    PubMed

    Buckley, Stephen; Usai, Donatella; Jakob, Tina; Radini, Anita; Hardy, Karen

    2014-01-01

    Accessing information on plant consumption before the adoption of agriculture is challenging. However, there is growing evidence for use of locally available wild plants from an increasing number of pre-agrarian sites, suggesting broad ecological knowledge. The extraction of chemical compounds and microfossils from dental calculus removed from ancient teeth offers an entirely new perspective on dietary reconstruction, as it provides empirical results on material that is already in the mouth. Here we present a suite of results from the multi-period Central Sudanese site of Al Khiday. We demonstrate the ingestion in both pre-agricultural and agricultural periods of Cyperus rotundus tubers. This plant is a good source of carbohydrates and has many useful medicinal and aromatic qualities, though today it is considered to be the world's most costly weed. Its ability to inhibit Streptococcus mutans may have contributed to the unexpectedly low level of caries found in the agricultural population. Other evidence extracted from the dental calculus includes smoke inhalation, dry (roasting) and wet (heating in water) cooking, a second plant possibly from the Triticaceae tribe and plant fibres suggestive of raw material preparation through chewing.

  4. Dental Calculus Reveals Unique Insights into Food Items, Cooking and Plant Processing in Prehistoric Central Sudan

    PubMed Central

    Buckley, Stephen; Usai, Donatella; Jakob, Tina; Radini, Anita; Hardy, Karen

    2014-01-01

    Accessing information on plant consumption before the adoption of agriculture is challenging. However, there is growing evidence for use of locally available wild plants from an increasing number of pre-agrarian sites, suggesting broad ecological knowledge. The extraction of chemical compounds and microfossils from dental calculus removed from ancient teeth offers an entirely new perspective on dietary reconstruction, as it provides empirical results on material that is already in the mouth. Here we present a suite of results from the multi-period Central Sudanese site of Al Khiday. We demonstrate the ingestion in both pre-agricultural and agricultural periods of Cyperus rotundus tubers. This plant is a good source of carbohydrates and has many useful medicinal and aromatic qualities, though today it is considered to be the world's most costly weed. Its ability to inhibit Streptococcus mutans may have contributed to the unexpectedly low level of caries found in the agricultural population. Other evidence extracted from the dental calculus includes smoke inhalation, dry (roasting) and wet (heating in water) cooking, a second plant possibly from the Triticaceae tribe and plant fibres suggestive of raw material preparation through chewing. PMID:25028938

  5. Effects of Riverbed Conductance on Stream Depletion

    NASA Astrophysics Data System (ADS)

    Lackey, G.; Neupauer, R. M.; Pitlick, J.

    2012-12-01

    In the western United States and other regions of the world where growing population and changing climates are threatening water supplies, accurate modeling of potential human impacts on water resources is becoming more important. Stream depletion, the reduction of surface water flow due to the extraction of groundwater from a hydraulically connected aquifer, is one of the more direct ways that development can alter water availability, degrade water quality and endanger aquatic habitats. These factors have made the accurate modeling of stream depletion an important step in the process of installing groundwater wells in regions that are susceptible to this phenomenon. Proper estimation of stream depletion requires appropriate parameterization of aquifer and streambed hydraulic properties. Although many studies have conducted numerical investigations to determine stream depletion at specific sites, they typically do not measure streambed hydraulic conductivity (Kr), but rather assume a representative value. In this work, we establish a hypothetical model aquifer that is 2000 m by 1600 m and has a meandering stream running through its center. The Kr of the model stream is varied from 1.0x10-9 m s-1 to 1.0x10-2 m s-1 in order to determine the sensitivity of the stream depletion calculations to this parameter. It was found that when Kr is in the lower part of this range, slight changes in K¬r lead to significant impacts on the calculated stream depletion values. We vary Kr along the stream channel according to naturally occurring patterns and demonstrate that alterations of the parameter over a few orders of magnitude can affect the estimated stream depletion caused by a well at a specified location. The numerical simulations show that the mean value of Kr and its spatial variability along the channel should be realistic to develop an accurate model of stream depletion.

  6. Depleted uranium: A DOE management guide

    SciTech Connect

    1995-10-01

    The U.S. Department of Energy (DOE) has a management challenge and financial liability in the form of 50,000 cylinders containing 555,000 metric tons of depleted uranium hexafluoride (UF{sub 6}) that are stored at the gaseous diffusion plants. The annual storage and maintenance cost is approximately $10 million. This report summarizes several studies undertaken by the DOE Office of Technology Development (OTD) to evaluate options for long-term depleted uranium management. Based on studies conducted to date, the most likely use of the depleted uranium is for shielding of spent nuclear fuel (SNF) or vitrified high-level waste (HLW) containers. The alternative to finding a use for the depleted uranium is disposal as a radioactive waste. Estimated disposal costs, utilizing existing technologies, range between $3.8 and $11.3 billion, depending on factors such as applicability of the Resource Conservation and Recovery Act (RCRA) and the location of the disposal site. The cost of recycling the depleted uranium in a concrete based shielding in SNF/HLW containers, although substantial, is comparable to or less than the cost of disposal. Consequently, the case can be made that if DOE invests in developing depleted uranium shielded containers instead of disposal, a long-term solution to the UF{sub 6} problem is attained at comparable or lower cost than disposal as a waste. Two concepts for depleted uranium storage casks were considered in these studies. The first is based on standard fabrication concepts previously developed for depleted uranium metal. The second converts the UF{sub 6} to an oxide aggregate that is used in concrete to make dry storage casks.

  7. Groundwater depletion's contribution to sea level rise increasing

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2011-11-01

    Since the turn of the twentieth century, industrial-scale redistribution of water from landlocked aquifers to the ocean has driven up the global average sea level by more than 12 centimeters. Between 1900 and 2008, roughly 4500 cubic kilometers of water was drawn from the ground, largely to feed an agricultural system increasingly reliant on irrigation. Of that 4500-cubic-kilometer total (nearly the volume of Lake Michigan), 1100 cubic kilometers were pumped out between 2000 and 2008 alone. This early-21st-century groundwater depletion was responsible for raising global sea level at a rate of 0.4 millimeter per year, an eighth of the observed total. These updated values, falling near the middle of the range of previous estimates, are the product of an investigation by Konikow that drew together a variety of volumetric measurements of groundwater storage.

  8. Anatomy of Depleted Interplanetary Coronal Mass Ejections

    NASA Astrophysics Data System (ADS)

    Kocher, M.; Lepri, S. T.; Landi, E.; Zhao, L.; Manchester, W. B., IV

    2017-01-01

    We report a subset of interplanetary coronal mass ejections (ICMEs) containing distinct periods of anomalous heavy-ion charge state composition and peculiar ion thermal properties measured by ACE/SWICS from 1998 to 2011. We label them “depleted ICMEs,” identified by the presence of intervals where C6+/C5+ and O7+/O6+ depart from the direct correlation expected after their freeze-in heights. These anomalous intervals within the depleted ICMEs are referred to as “Depletion Regions.” We find that a depleted ICME would be indistinguishable from all other ICMEs in the absence of the Depletion Region, which has the defining property of significantly low abundances of fully charged species of helium, carbon, oxygen, and nitrogen. Similar anomalies in the slow solar wind were discussed by Zhao et al. We explore two possibilities for the source of the Depletion Region associated with magnetic reconnection in the tail of a CME, using CME simulations of the evolution of two Earth-bound CMEs described by Manchester et al.

  9. A new definition of maternal depletion syndrome.

    PubMed Central

    Winkvist, A; Rasmussen, K M; Habicht, J P

    1992-01-01

    BACKGROUND. Although the term "maternal depletion syndrome" has been commonly used to explain poor maternal and infant health, whether such a syndrome actually exists remains unclear. This uncertainty may be due to the lack of a clear definition of the syndrome and the absence of theoretical frameworks that account for the many factors related to reproductive nutrition. METHODS. We propose a new definition of maternal depletion syndrome within a framework that accounts for potential confounding factors. RESULTS. Our conceptual framework distinguishes between childbearing pattern and inadequate diet as causes of poor maternal health; hence, our definition of maternal depletion syndrome has both biological and practical meaning. The new definition is based on overall change in maternal nutritional status over one reproductive cycle in relation to possible depletion and repletion phases and in relation to initial nutritional status. CONCLUSIONS. The empirical application of this approach should permit the testing of the existence of maternal depletion syndrome in the developing world, and the distinction between populations where family planning will alleviate maternal depletion and those in which an improved diet is also necessary. PMID:1566948

  10. Satellite-based estimates of groundwater depletion in India.

    PubMed

    Rodell, Matthew; Velicogna, Isabella; Famiglietti, James S

    2009-08-20

    Groundwater is a primary source of fresh water in many parts of the world. Some regions are becoming overly dependent on it, consuming groundwater faster than it is naturally replenished and causing water tables to decline unremittingly. Indirect evidence suggests that this is the case in northwest India, but there has been no regional assessment of the rate of groundwater depletion. Here we use terrestrial water storage-change observations from the NASA Gravity Recovery and Climate Experiment satellites and simulated soil-water variations from a data-integrating hydrological modelling system to show that groundwater is being depleted at a mean rate of 4.0 +/- 1.0 cm yr(-1) equivalent height of water (17.7 +/- 4.5 km(3) yr(-1)) over the Indian states of Rajasthan, Punjab and Haryana (including Delhi). During our study period of August 2002 to October 2008, groundwater depletion was equivalent to a net loss of 109 km(3) of water, which is double the capacity of India's largest surface-water reservoir. Annual rainfall was close to normal throughout the period and we demonstrate that the other terrestrial water storage components (soil moisture, surface waters, snow, glaciers and biomass) did not contribute significantly to the observed decline in total water levels. Although our observational record is brief, the available evidence suggests that unsustainable consumption of groundwater for irrigation and other anthropogenic uses is likely to be the cause. If measures are not taken soon to ensure sustainable groundwater usage, the consequences for the 114,000,000 residents of the region may include a reduction of agricultural output and shortages of potable water, leading to extensive socioeconomic stresses.

  11. Biodeterioration agents: Bacterial and fungal diversity dwelling in or on the pre-historic rock-paints of Kabra-pahad, India

    PubMed Central

    Biswas, Jayant; Sharma, Kavita; Harris, K.K.; Rajput, Yogita

    2013-01-01

    Background and Objectives In the last few decades, losses of our cultural heritage due to biodeteriorationare beinghighly recognized. From museum objects to rock monuments, the microbial biodeterioration agents are found to be the most destructive. Possibilities for proper preservative measure(s) are always more when it is only a monument, statue, museum article, or pre-historic art in any small subterranean cave. Nevertheless, preservation/protection of the footprints occupying a big area, lying scattered in a very negligible manner requires safeguard against several deterioration factors; right from various physical, chemical and biological agents which are indeed interrelated to each other. Materials and Methods In the present study, some microbial communities possibly responsible for deteriorating the rocks of Kabra-pahad, where the most famous pre-historic rock paints of India prevail have been identified. The diversity of fungi and bacteria present in the stone crust of the infected areas has been studied by employing standard laboratory methods. Results The cultivated cultures confirmed total fifteen fungal species, among which Aspergillus group were the most dominant. Among bacteria, total 80 numbers of colonies were observed that dominated by two major groups; Micrococcus.spp and Staphylococcus spp. Conclusion The pre-historic footprint in the form of rock paints in Kabra-pahad of district Raigarh, Chhattisgarh, India is lying in a very deteriorated manner. In the present study, we have tried to identify few major deteriorating factors that are responsible for such degradation of our existing pre-historic footprints. PMID:24475341

  12. Agriculture and deforestation in the tropics: a critical theoretical and empirical review.

    PubMed

    Benhin, James K A

    2006-02-01

    Despite the important role that tropical forests play in human existence, their depletion, especially in the developing world, continue relentlessly. Agriculture has been cited as the major cause of this depletion. This paper discusses two main theoretical underpinnings for the role of agriculture in tropical deforestation. First, the forest biomass as input in agricultural production, and second, the competition between agriculture and forestry underlined by their relative marginal benefits. These are supported by empirical evidence from selected countries in Africa and South America. The paper suggests a need to find a win-win situation to control the spate of tropical deforestation. This may imply improved technologies in the agriculture sector in the developing world, which would lead both to increased production in the agriculture sector, and would also help control the use of tropical forest as an input in agriculture production.

  13. GPR study of a prehistoric archaeological site near Point Barrow, Alaska

    NASA Astrophysics Data System (ADS)

    Herman, R. B.; Jensen, A. M.

    2012-12-01

    A ground penetrating radar (GPR) study was performed on the prehistoric Thule cemetery site near Point Barrow, Alaska. The goals of this study were (a) to test this technology in this type of polar environment, and (b) to search for burials and other archaeological features in a location in imminent danger from ocean erosion. The Nuvuk site is currently eroding at an average rate measured at over 6 m/year. Prior archaeological work at the site had recovered over 80 burials with nearly 100 individuals represented, all of which were less than 1 m below surface, and detectable with small test pits. In addition, the first coastal Ipiutak occupation known north of Point Hope had been recently discovered, at a depth of nearly 2m below surface, in the erosion face. The occupation appeared to have been terminated by a large storm which overwashed the site, leaving a strandline immediately superimposed on the living surface. After that, approximately 1.5 m of sterile gravels had been deposited before the surface on which the Thule people were living formed. Both occupations are of considerable scientific interest. The matrix at the site consists of unconsolidated beach gravels, which necessitates opening large surface areas or use of shoring to test even small units to the depths of the Ipiutak deposit (approximately 8m x 8m at the surface to test 1m x 1m at 2m depth). Such excavations promote erosion, and are very costly in terms of time and labor, so a means to detect features buried at depths greater than those exposed by shovel test pits was desirable. GPR seemed a likely candidate, but it had not been used in such conditions before, and thus it was necessary to test it thoroughly prior to relying on GPR to eliminate areas from physical testing. The GPR imaged the subsurface to a depth of 3 meters at a frequency of 500MHz. Meter-deep test pits were placed at 2-meter intervals in the survey area in a grid pattern since the efficacy of the technology had yet to be shown

  14. Evidence of four prehistoric supernovae <250 pc from Earth during the past 50,000 years

    NASA Astrophysics Data System (ADS)

    Firestone, R. B.

    2009-12-01

    Analysis of the radiocarbon record for the past 50 ka indicates that four supernovae exploded near Earth 44 ka (~110 pc), 37 ka (~180 pc), 32 ka (~160 pc), and 22 ka (250 pc) ago. Each SN left a unique signature in the radiocarbon record consisting of a sudden increase in atmospheric radiocarbon at the time of the initial explosion due to the arrival of γ-rays and neutrinos, followed by a much larger increase in global radiocarbon spanning centuries due to cosmic rays produced by diffusive shock in the SN remnant, and concluding with the decay of the excess global 14C produced in these events. Temporal evolution of this signature is identical for each SN as if it were a “standard candle”. The ~22 ka SN is most likely the Vela SN that is known to have exploded 10-30 ka ago 250 pc from Earth. The distances of the other SNe are calculated from the relative amounts of radiocarbon produced on Earth with respect to the Vela SN assuming a 1/r2 relationship. The rate of these nearby prehistoric SNe is comparable to that expected from the more distant historical SNe observed during the past 1000 years and it is consistent with the galactic cosmic ray rate at Earth. Global radiocarbon doubled after the ~44 ka SN which exploded 110 pc from Earth, a distance consistent with the Upper Scorpius OB Association. It coincides with the advent of modern man, mutations leading to the development of type A and B blood, and major megafaunal extinctions in Southeast Asia. An exponential fit to the past 18 ka of INTCAL04 Δ14C data gives a half-life of 5700±700 yr, consistent with the half-life of 14C (5730 yr), and establishes an absolute scale of Δ14C=5±2% for T=0 in 1950. Small variations about the exponential decay curve correlate with observed changes in the strength of Earth’s virtual axial dipole moment (VADM). Analysis of the energy necessary to produce the excess global radiocarbon indicates that these SNe explosions released ~3x1050 ergs of energy into the production

  15. Barometry of lavas from the 1951 eruption of Fogo, Cape Verde Islands: Implications for historic and prehistoric magma plumbing systems

    NASA Astrophysics Data System (ADS)

    Hildner, Elliot; Klügel, Andreas; Hansteen, Thor H.

    2012-03-01

    Fogo is one of the most active oceanic volcanoes in the world. The island was affected by a prehistoric giant lateral collapse that decapitated the summit of the former Monte Amarelo volcano. Subsequent volcanism has partly filled the collapse scar and built up the present-day Cha das Caldeiras plain and the Pico do Fogo stratovolcano. We have conducted a thermobarometric study of historic and prehistoric, basanitic to tephritic rocks in order to gain insight into Fogo's magma plumbing system and the impact of the collapse event on fractionation depths. A main focus was the penultimate 1951 eruption, which produced basanites to tephrites (5.0-8.2 wt.% MgO) at two sites south and northwest of Pico do Fogo. Clinopyroxene-melt barometry of phenocrysts yields a well-confined pressure range of 480-650 MPa for the final crystallization level. Microthermometric data of CO2-dominated fluid inclusions in olivine and clinopyroxene phenocrysts yield systematically lower pressures of 250-430 MPa. Inclusions in cumulate xenoliths yield pressures of 100-290 MPa. The combined data indicate pre-eruptive magma storage in the uppermost mantle between 17 and 22 km depth and syn-eruptive short-term magma stalling within the lower crust at 8-13 km depth. The lower pressures revealed by fluid inclusions in xenoliths may indicate that they originate from pre-1951 magma pulses that stalled and crystallized at variable levels in the crust. There is, however, no petrologic evidence for persistent crustal magma chambers. Clinopyroxene-melt barometric data of other historic and prehistoric eruptions indicate that magma storage and differentiation occurred in the uppermost mantle at pressures between 420 and 870 MPa (15-30 km depth) throughout the subaerial evolution of Fogo. Our data indicate that fractionation depths decreased significantly during a period of about 100 ka representing a strong growth phase of Fogo edifice leading up to the giant Monte Amarelo flank collapse at 123-62 ka

  16. Theme: Agricultural Literacy.

    ERIC Educational Resources Information Center

    Deeds, Jacquelyn P.; And Others

    1991-01-01

    Six theme articles attempt to define and advocate agricultural literacy, review the status of K-8 agricultural literacy programs in states, discuss an Oklahoma study of agricultural literacy, clarify the meaning of sustainable agriculture, and describe the Future Farmers of America's Food for America program for elementary students. (SK)

  17. Handbook of Agricultural Geophysics

    USDA-ARS?s Scientific Manuscript database

    Geophysical methods continue to show great promise for use in agriculture. The term “agricultural geophysics” denotes a subdiscipline of geophysics that is focused only on agricultural applications. The Handbook of Agricultural Geophysics was compiled to include a comprehensive overview of the geoph...

  18. Theme: Agricultural Literacy.

    ERIC Educational Resources Information Center

    Deeds, Jacquelyn P.; And Others

    1991-01-01

    Six theme articles attempt to define and advocate agricultural literacy, review the status of K-8 agricultural literacy programs in states, discuss an Oklahoma study of agricultural literacy, clarify the meaning of sustainable agriculture, and describe the Future Farmers of America's Food for America program for elementary students. (SK)

  19. Vocational Agriculture Computer Handbook.

    ERIC Educational Resources Information Center

    Kentucky State Dept. of Education, Frankfort.

    This document is a catalog of reviews of computer software suitable for use in vocational agriculture programs. The reviews were made by vocational agriculture teachers in Kentucky. The reviews cover software on the following topics: farm management, crop production, livestock production, horticulture, agricultural mechanics, general agriculture,…

  20. Vocational Agriculture Computer Handbook.

    ERIC Educational Resources Information Center

    Kentucky State Dept. of Education, Frankfort.

    This document is a catalog of reviews of computer software suitable for use in vocational agriculture programs. The reviews were made by vocational agriculture teachers in Kentucky. The reviews cover software on the following topics: farm management, crop production, livestock production, horticulture, agricultural mechanics, general agriculture,…

  1. Agricultural trade and the global phosphorus cycle

    NASA Astrophysics Data System (ADS)

    Schipanski, M.; Bennett, E.; Riskin, S.; Porder, S.

    2012-12-01

    Trends of increasing agricultural trade, increased concentration of livestock production systems, and increased human consumption of livestock products influence the distribution of nutrients across the global landscape. Phosphorus (P) represents a unique management challenge as we are rapidly depleting mineable reserves of this essential and non-renewable resource. At the same time, its overuse can lead to pollution of aquatic ecosystems. We analyzed the relative contributions of food crop, feed crop, and livestock product trade to P flows through agricultural soils for twelve countries from 1961 to 2007. We then used case studies of P fertilizer use in the world's three major soybean export regions: Iowa (USA), Mato Grosso (Brazil), and Buenos Aires (Argentina) to examine the influence of historical P management and soil types on agriculture's environmental consequences. Due to the intensification of agricultural production, average soil surface P balances more than tripled from 6 to 21 kg P per ha between 1961 and 2007 for the twelve study countries. Consequently, countries that are primarily agricultural exporters carried increased risks for water pollution or, for Argentina, reduced soil fertility due to soil P mining to support exports. In 2007, nations imported food and feed from regions with higher apparent P fertilizer use efficiencies than if those crops were produced domestically. However, this was largely because imports were sourced from regions depleting soil P resources to support export crop production. In addition, the pattern of regional specialization and intensification of production systems also reduced the potential to recycle P resources, with greater implications for livestock production than crop production. In a globalizing world, it will be increasingly important to integrate biophysical constraints of our natural resources and environmental impacts of agricultural systems into trade policy and agreements and to develop mechanisms that

  2. New Approach For Prediction Groundwater Depletion

    NASA Astrophysics Data System (ADS)

    Moustafa, Mahmoud

    2017-01-01

    Current approaches to quantify groundwater depletion involve water balance and satellite gravity. However, the water balance technique includes uncertain estimation of parameters such as evapotranspiration and runoff. The satellite method consumes time and effort. The work reported in this paper proposes using failure theory in a novel way to predict groundwater saturated thickness depletion. An important issue in the failure theory proposed is to determine the failure point (depletion case). The proposed technique uses depth of water as the net result of recharge/discharge processes in the aquifer to calculate remaining saturated thickness resulting from the applied pumping rates in an area to evaluate the groundwater depletion. Two parameters, the Weibull function and Bayes analysis were used to model and analyze collected data from 1962 to 2009. The proposed methodology was tested in a nonrenewable aquifer, with no recharge. Consequently, the continuous decline in water depth has been the main criterion used to estimate the depletion. The value of the proposed approach is to predict the probable effect of the current applied pumping rates on the saturated thickness based on the remaining saturated thickness data. The limitation of the suggested approach is that it assumes the applied management practices are constant during the prediction period. The study predicted that after 300 years there would be an 80% probability of the saturated aquifer which would be expected to be depleted. Lifetime or failure theory can give a simple alternative way to predict the remaining saturated thickness depletion with no time-consuming processes such as the sophisticated software required.

  3. Validating Prehistoric and Current Social Phenomena Upon the Landscape of the Peten, Guatemala

    NASA Technical Reports Server (NTRS)

    Sever, Thomas L.

    1997-01-01

    The Peten, once inhabited by a population of several million before the collapse of the ancient Maya in the 10th and 11th centuries, is being repopulated toward its former demographic peak. Environmental dynamics, however, impose severe constraints to further development. Current practices in subsistence, commercial agriculture, and cattle raising are causing rapid deforestation on a scale that can only result in soil loss and regional degradation. In view of the current deforestation trends, the question emerges as to how millions of ancient Maya lived successfully in the area for centuries when relatively fewer occupants today threaten the sustainability of the landscape with current agricultural practices. The use of remote sensing technology is a cost-effective methodology for addressing issues in Maya archeology as well as monitoring the environmental impacts being experienced by the current population.

  4. Validating Prehistoric and Current Social Phenomena Upon the Landscape of the Peten, Guatemala

    NASA Technical Reports Server (NTRS)

    Sever, Thomas L.

    1997-01-01

    The Peten, once inhabited by a population of several million before the collapse of the ancient Maya in the 10th and 11th centuries, is being repopulated toward its former demographic peak. Environmental dynamics, however, impose severe constraints to further development. Current practices in subsistence, commercial agriculture, and cattle raising are causing rapid deforestation on a scale that can only result in soil loss and regional degradation. In view of the current deforestation trends, the question emerges as to how millions of ancient Maya lived successfully in the area for centuries when relatively fewer occupants today threaten the sustainability of the landscape with current agricultural practices. The use of remote sensing technology is a cost-effective methodology for addressing issues in Maya archeology as well as monitoring the environmental impacts being experienced by the current population.

  5. Technical synthesis of prehistoric archaeological investigations on the Savannah River Site, Aiken and Barnwell Counties, South Carolina

    SciTech Connect

    Sassaman, K.E.; Brooks, M.J.; Hanson, G.T.; Anderson, D.G.

    1989-12-01

    Archaeological investigations on the United States Department of Energy's (DOE) Savannah River Site (SRS) in south Carolina span 16 years and continue today through a cooperative agreement between DOE and the South Carolina Institute of Archaeology and Anthropology (SCIAA), University of South Carolina. The Savannah River Archaeological Research Program (SRARP) of SCIAA has been and continues to be the sole archaeological consultant for DOE-SRS. This report documents technical aspects of all prehistoric archaeological research conducted by the SRARP between 1973 and 1987. Further, this report provides interpretative contexts for archaeological resources as a basis for an archaeological resource plan reported elsewhere (SRARP 1989), and as a comprehensive statement of our current understanding of Native American prehistory and history.

  6. Earthquake catalog for estimation of maximum earthquake magnitude, Central and Eastern United States: Part A, Prehistoric earthquakes

    USGS Publications Warehouse

    Wheeler, Russell L.

    2014-01-01

    Computation of probabilistic earthquake hazard requires an estimate of Mmax, the maximum earthquake magnitude thought to be possible within a specified geographic region. This report is Part A of an Open-File Report that describes the construction of a global catalog of moderate to large earthquakes, from which one can estimate Mmax for most of the Central and Eastern United States and adjacent Canada. The catalog and Mmax estimates derived from it were used in the 2014 edition of the U.S. Geological Survey national seismic-hazard maps. This Part A discusses prehistoric earthquakes that occurred in eastern North America, northwestern Europe, and Australia, whereas a separate Part B deals with historical events.

  7. Isotope sourcing of prehistoric willow and tule textiles recovered from western Great Basin rock shelters and caves - proof of concept

    USGS Publications Warehouse

    Benson, L.V.; Hattori, E.M.; Taylor, H.E.; Poulson, S.R.; Jolie, E.A.

    2006-01-01

    Isotope and trace-metal analyses were used to determine the origin of plants used to manufacture prehistoric textiles (basketry and matting) from archaeological sites in the western Great Basin. Research focused on strontium (87Sr/86Sr) and oxygen (18O/16O) isotope ratios of willow (Salix sp.) and tule (Schoenoplectus sp.), the dominant raw materials in Great Basin textiles. The oxygen-isotope data indicated that the willow and tule used to produce the textiles were harvested from the banks of rivers or in marshes characterized by flowing water and not from lakes or sinks. The strontium-isotope data were useful in showing which plants came from the Humboldt River and which came from rivers headed in the Sierra Nevada.

  8. mtDNA analysis of a prehistoric Oneota population: implications for the peopling of the New World.

    PubMed Central

    Stone, A C; Stoneking, M

    1998-01-01

    mtDNA was successfully extracted from 108 individuals from the Norris Farms Oneota, a prehistoric Native American population, to compare the mtDNA diversity from a pre-Columbian population with contemporary Native American and Asian mtDNA lineages and to examine hypotheses about the peopling of the New World. Haplogroup and hypervariable region I sequence data indicate that the lineages from haplogroups A, B, C, and D are the most common among Native Americans but that they were not the only lineages brought into the New World from Asia. The mtDNA evidence does not support the three-wave hypothesis of migration into the New World but rather suggests a single "wave" of people with considerable mtDNA diversity that exhibits a signature of expansion 23,000-37,000 years ago. PMID:9545408

  9. A prehistoric lahar-dammed lake and eruption of Mount Pinatubo described in a Philippine aborigine legend

    NASA Astrophysics Data System (ADS)

    Rodolfo, Kelvin S.; Umbal, Jesse V.

    2008-10-01

    The prehistoric eruptions of Mount Pinatubo have followed a cycle: centuries of repose terminated by a caldera-forming eruption with large pyroclastic flows; a post-eruption aftermath of rain-triggered lahars in surrounding drainages and dome-building that fills the caldera; and then another long quiescent period. During and after the eruptions lahars descending along volcano channels may block tributaries from watersheds beyond Pinatubo, generating natural lakes. Since the 1991 eruption, the Mapanuepe River valley in the southwestern sector of the volcano has been the site of a large lahar-dammed lake. Geologic evidence indicates that similar lakes have occupied this site at least twice before. An Ayta legend collected decades before Mount Pinatubo was recognized as a volcano describes what is probably the younger of these lakes, and the caldera-forming eruption that destroyed it.

  10. The geological record of prehistorical tsunami at a coastal area of Beppu Bay in eastern Kyushu, Japan

    NASA Astrophysics Data System (ADS)

    Yamada, M.; Fujino, S.; Chiba, T.; Shinozaki, T.; Okuwaki, R.; Takeda, D.

    2015-12-01

    Tsunamis are typically generated by plate-boundary ruptures at subduction zones, but also vertical displacement associated with intraplate earthquakes. Historical written records documented that coasts of Beppu Bay, eastern Kyushu, Japan was devastated by a tsunami associated with the AD 1596 Keicho-Bungo earthquake (M7.0). It is considered that the earthquake occurred at submarine active faults in the bay. The aim of this study is to unravel the occurrence age and source of tsunamis that struck the coast of the bay in prehistorical ages. This study may also make a contribution to the understanding of tsunami-generating system at submarine active faults. We conducted a coring survey at paddy fields along the north coast of the bay. The 10 cm thick muddy sand layer with a few granules (hereinafter, sand layer), bounded by sharp contacts, was evident in the 1.7 m long sediment core taken at 700 m from the shoreline. Plant materials obtained from mud above the sand layer was dated to 1880-2000 cal. yr BP. Sharp contacts between sand and surrounding muds imply that the sand layer is formed by a sudden event. Existence of mud clast in the sand layer indicates erosion of surface mud. There were no brackish-marine diatoms in surrounding mud, but they accounted for 5-6% of the total within the sand layer, indicating that the sand grains were sourced at least in part from brackish-marine environment. Mean grain size/sorting of the sand layer and beach sand were 2.31/0.94 and 2.03/0.41 phi. The difference in sorting probably suggests that the sand layer partly contains the onshore sediments eroded in inundation process. Additional coring surveys would clarify the distribution of prehistorical tsunami deposits and source of past tsunamis.

  11. Mitochondrial genome diversity at the Bering Strait area highlights prehistoric human migrations from Siberia to northern North America.

    PubMed

    Dryomov, Stanislav V; Nazhmidenova, Azhar M; Shalaurova, Sophia A; Morozov, Igor V; Tabarev, Andrei V; Starikovskaya, Elena B; Sukernik, Rem I

    2015-10-01

    The patterns of prehistoric migrations across the Bering Land Bridge are far from being completely understood: there still exists a significant gap in our knowledge of the population history of former Beringia. Here, through comprehensive survey of mitochondrial DNA genomes retained in 'relic' populations, the Maritime Chukchi, Siberian Eskimos, and Commander Aleuts, we explore genetic contribution of prehistoric Siberians/Asians to northwestern Native Americans. Overall, 201 complete mitochondrial sequences (52 new and 149 published) were selected in the reconstruction of trees encompassing mtDNA lineages that are restricted to Coastal Chukotka and Alaska, the Canadian Arctic, Greenland, and the Aleutian chain. Phylogeography of the resulting mtDNA genomes (mitogenomes) considerably extends the range and intrinsic diversity of haplogroups (eg, A2a, A2b, D2a, and D4b1a2a1) that emerged and diversified in postglacial central Beringia, defining independent origins of Neo-Eskimos versus Paleo-Eskimos, Aleuts, and Tlingit (Na-Dene). Specifically, Neo-Eskimos, ancestral to modern Inuit, not only appear to be of the High Arctic origin but also to harbor Altai/Sayan-related ancestry. The occurrence of the haplogroup D2a1b haplotypes in Chukotka (Sireniki) introduces the possibility that the traces of Paleo-Eskimos have not been fully erased by spread of the Neo-Eskimos or their descendants. Our findings are consistent with the recurrent gene flow model of multiple streams of expansions to northern North America from northeastern Eurasia in late Pleistocene-early Holocene.

  12. Mitochondrial genome diversity at the Bering Strait area highlights prehistoric human migrations from Siberia to northern North America

    PubMed Central

    Dryomov, Stanislav V; Nazhmidenova, Azhar M; Shalaurova, Sophia A; Morozov, Igor V; Tabarev, Andrei V; Starikovskaya, Elena B; Sukernik, Rem I

    2015-01-01

    The patterns of prehistoric migrations across the Bering Land Bridge are far from being completely understood: there still exists a significant gap in our knowledge of the population history of former Beringia. Here, through comprehensive survey of mitochondrial DNA genomes retained in ‘relic' populations, the Maritime Chukchi, Siberian Eskimos, and Commander Aleuts, we explore genetic contribution of prehistoric Siberians/Asians to northwestern Native Americans. Overall, 201 complete mitochondrial sequences (52 new and 149 published) were selected in the reconstruction of trees encompassing mtDNA lineages that are restricted to Coastal Chukotka and Alaska, the Canadian Arctic, Greenland, and the Aleutian chain. Phylogeography of the resulting mtDNA genomes (mitogenomes) considerably extends the range and intrinsic diversity of haplogroups (eg, A2a, A2b, D2a, and D4b1a2a1) that emerged and diversified in postglacial central Beringia, defining independent origins of Neo-Eskimos versus Paleo-Eskimos, Aleuts, and Tlingit (Na-Dene). Specifically, Neo-Eskimos, ancestral to modern Inuit, not only appear to be of the High Arctic origin but also to harbor Altai/Sayan-related ancestry. The occurrence of the haplogroup D2a1b haplotypes in Chukotka (Sireniki) introduces the possibility that the traces of Paleo-Eskimos have not been fully erased by spread of the Neo-Eskimos or their descendants. Our findings are consistent with the recurrent gene flow model of multiple streams of expansions to northern North America from northeastern Eurasia in late Pleistocene–early Holocene. PMID:25564040

  13. Study of a prehistoric landslide using seismic reflection methods integrated with geological data in the Wasatch Mountains, Utah, USA

    USGS Publications Warehouse

    Tingey, B.E.; McBride, J.H.; Thompson, T.J.; Stephenson, W.J.; South, J.V.; Bushman, M.

    2007-01-01

    An integration of geological and geophysical techniques characterizes the internal and basal structure of a landslide along the western margin of the Wasatch Mountains in northern Utah, USA. The study area is within a region of planned and continuing residential development. The Little Valley Landslide is a prehistoric landslide as old as 13??ka B.P. Drilling and trenching at the site indicate that the landslide consists of chaotic and disturbed weathered volcanic material derived from Tertiary age volcanic rocks that comprise a great portion of the Wasatch Range. Five short high-resolution common mid-point seismic reflection profiles over selected portions of the site examine the feasibility of using seismic reflection to study prehistoric landslides in the Wasatch Mountain region. Due to the expected complexity of the near-surface geology, we have pursued an experimental approach in the data processing, examining the effects of muting first arrivals, frequency filtering, model-based static corrections, and seismic migration. The results provide a framework for understanding the overall configuration of the landslide, its basal (failure) surface, and the structure immediately underlying this surface. A glide surface or de??collement is interpreted to underlie the landslide suggesting a large mass movement. The interpretation of a glide surface is based on the onset of coherent reflectivity, calibrated by information from a borehole located along one of the seismic profiles. The glide surface is deepest in the center portion of the landslide and shallows up slope, suggesting a trough-like feature. This study shows that seismic reflection techniques can be successfully used in complex alpine landslide regions to (1) provide a framework in which to link geological data and (2) reduce the need for an extensive trenching and drilling program. ?? 2007 Elsevier B.V. All rights reserved.

  14. Ancient water bottle use and polycyclic aromatic hydrocarbon (PAH) exposure among California Indians: a prehistoric health risk assessment.

    PubMed

    Sholts, Sabrina B; Smith, Kevin; Wallin, Cecilia; Ahmed, Trifa M; Wärmländer, Sebastian K T S

    2017-06-23

    Polycyclic aromatic hydrocarbons (PAHs) are the main toxic compounds in natural bitumen, a fossil material used by modern and ancient societies around the world. The adverse health effects of PAHs on modern humans are well established, but their health impacts on past populations are unclear. It has previously been suggested that a prehistoric health decline among the native people living on the California Channel Islands may have been related to PAH exposure. Here, we assess the potential health risks of PAH exposure from the use and manufacture of bitumen-coated water bottles by ancient California Indian societies. We replicated prehistoric bitumen-coated water bottles with traditional materials and techniques of California Indians, based on ethnographic and archaeological evidence. In order to estimate PAH exposure related to water bottle manufacture and use, we conducted controlled experiments to measure PAH contamination 1) in air during the manufacturing process and 2) in water and olive oil stored in a completed bottle for varying periods of time. Samples were analyzed with gas chromatography/mass spectrometry (GC/MS) for concentrations of the 16 PAHs identified by the US Environmental Protection Agency (EPA) as priority pollutants. Eight PAHs were detected in concentrations of 1-10 μg/m(3) in air during bottle production and 50-900 ng/L in water after 2 months of storage, ranging from two-ring (naphthalene and methylnaphthalene) to four-ring (fluoranthene) molecules. All 16 PAHs analyzed were detected in olive oil after 2 days (2 to 35 μg/kg), 2 weeks (3 to 66 μg/kg), and 2 months (5 to 140 μg/kg) of storage. For ancient California Indians, water stored in bitumen-coated water bottles was not a significant source of PAH exposure, but production of such bottles could have resulted in harmful airborne PAH exposure.

  15. 3D Recording methodology applied to the Grotta Scritta Prehistoric Rock-Shelter in Olmeta-Di-Capocorso (Corsica, France)

    NASA Astrophysics Data System (ADS)

    Grussenmeyer, P.; Burens, A.; Guillemin, S.; Alby, E.; Allegrini Simonetti, F.; Marchetti, M.-L.

    2015-08-01

    The Grotta Scritta I prehistoric site is located on the west side of Cap Corse, in the territory of the municipality of Olmeta-di- Capocorso (Haute-Corse, France). This rock shelter is located on a western spur of the mountains La Serra, at 412 m height above sea level. In the regional context of a broad set of megalithic burial sites (regions Nebbiu and Agriates) and a rich insular prehistoric rock art with several engraved patterns (mainly geometric), the Grotta Scritta is the only site with painted depictions of Corsica. Around twenty parietal depictions are arranged in the upper part of the rock-shelter and takes advantage of the microtopography of the wall. Today, the Grotta Scritta is a vulnerable site, made fragile by the action of time and man. The 3D scanning of the rockshelter and paintings of the Grotta Scritta was carried out by surveyors and archaeologists from INSA Strasbourg and from UMR 5602 GEODE (Toulouse), by combining accurate terrestrial laser scanning and photogrammetry techniques. These techniques are based on a full 3D documentation without contact of the rock-shelter paintings. The paper presents the data acquisition methodology followed by an overview of data processing solutions based on both imaging and laser scanning. Several deliverables as point clouds, meshed models, textured models and orthoimages are proposed for the documentation. Beyond their usefulness in terms of valorization, communication and virtual restitution, the proposed models also provide support tools for the analysis and perception of the complexity of the volumes of the shelter (namely for the folded forms of the dome housing the paintings) as well as for the accuracy of the painted depictions recorded on the orthophotos processed from the 3D model.

  16. The New MCNP6 Depletion Capability

    SciTech Connect

    Fensin, Michael Lorne; James, Michael R.; Hendricks, John S.; Goorley, John T.

    2012-06-19

    The first MCNP based inline Monte Carlo depletion capability was officially released from the Radiation Safety Information and Computational Center as MCNPX 2.6.0. Both the MCNP5 and MCNPX codes have historically provided a successful combinatorial geometry based, continuous energy, Monte Carlo radiation transport solution for advanced reactor modeling and simulation. However, due to separate development pathways, useful simulation capabilities were dispersed between both codes and not unified in a single technology. MCNP6, the next evolution in the MCNP suite of codes, now combines the capability of both simulation tools, as well as providing new advanced technology, in a single radiation transport code. We describe here the new capabilities of the MCNP6 depletion code dating from the official RSICC release MCNPX 2.6.0, reported previously, to the now current state of MCNP6. NEA/OECD benchmark results are also reported. The MCNP6 depletion capability enhancements beyond MCNPX 2.6.0 reported here include: (1) new performance enhancing parallel architecture that implements both shared and distributed memory constructs; (2) enhanced memory management that maximizes calculation fidelity; and (3) improved burnup physics for better nuclide prediction. MCNP6 depletion enables complete, relatively easy-to-use depletion calculations in a single Monte Carlo code. The enhancements described here help provide a powerful capability as well as dictate a path forward for future development to improve the usefulness of the technology.

  17. Depletion sensitivity predicts unhealthy snack purchases.

    PubMed

    Salmon, Stefanie J; Adriaanse, Marieke A; Fennis, Bob M; De Vet, Emely; De Ridder, Denise T D

    2016-01-01

    The aim of the present research is to examine the relation between depletion sensitivity - a novel construct referring to the speed or ease by which one's self-control resources are drained - and snack purchase behavior. In addition, interactions between depletion sensitivity and the goal to lose weight on snack purchase behavior were explored. Participants included in the study were instructed to report every snack they bought over the course of one week. The dependent variables were the number of healthy and unhealthy snacks purchased. The results of the present study demonstrate that depletion sensitivity predicts the amount of unhealthy (but not healthy) snacks bought. The more sensitive people are to depletion, the more unhealthy snacks they buy. Moreover, there was some tentative evidence that this relation is more pronounced for people with a weak as opposed to a strong goal to lose weight, suggesting that a strong goal to lose weight may function as a motivational buffer against self-control failures. All in all, these findings provide evidence for the external validity of depletion sensitivity and the relevance of this construct in the domain of eating behavior. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. The new MCNP6 depletion capability

    SciTech Connect

    Fensin, M. L.; James, M. R.; Hendricks, J. S.; Goorley, J. T.

    2012-07-01

    The first MCNP based in-line Monte Carlo depletion capability was officially released from the Radiation Safety Information and Computational Center as MCNPX 2.6.0. Both the MCNP5 and MCNPX codes have historically provided a successful combinatorial geometry based, continuous energy, Monte Carlo radiation transport solution for advanced reactor modeling and simulation. However, due to separate development pathways, useful simulation capabilities were dispersed between both codes and not unified in a single technology. MCNP6, the next evolution in the MCNP suite of codes, now combines the capability of both simulation tools, as well as providing new advanced technology, in a single radiation transport code. We describe here the new capabilities of the MCNP6 depletion code dating from the official RSICC release MCNPX 2.6.0, reported previously, to the now current state of MCNP6. NEA/OECD benchmark results are also reported. The MCNP6 depletion capability enhancements beyond MCNPX 2.6.0 reported here include: (1) new performance enhancing parallel architecture that implements both shared and distributed memory constructs; (2) enhanced memory management that maximizes calculation fidelity; and (3) improved burnup physics for better nuclide prediction. MCNP6 depletion enables complete, relatively easy-to-use depletion calculations in a single Monte Carlo code. The enhancements described here help provide a powerful capability as well as dictate a path forward for future development to improve the usefulness of the technology. (authors)

  19. Ego depletion in visual perception: Ego-depleted viewers experience less ambiguous figure reversal.

    PubMed

    Wimmer, Marina C; Stirk, Steven; Hancock, Peter J B

    2017-02-22

    This study examined the effects of ego depletion on ambiguous figure perception. Adults (N = 315) received an ego depletion task and were subsequently tested on their inhibitory control abilities that were indexed by the Stroop task (Experiment 1) and their ability to perceive both interpretations of ambiguous figures that was indexed by reversal (Experiment 2). Ego depletion had a very small effect on reducing inhibitory control (Cohen's d = .15) (Experiment 1). Ego-depleted participants had a tendency to take longer to respond in Stroop trials. In Experiment 2, ego depletion had small to medium effects on the experience of reversal. Ego-depleted viewers tended to take longer to reverse ambiguous figures (duration to first reversal) when naïve of the ambiguity and experienced less reversal both when naïve and informed of the ambiguity. Together, findings suggest that ego depletion has small effects on inhibitory control and small to medium effects on bottom-up and top-down perceptual processes. The depletion of cognitive resources can reduce our visual perceptual experience.

  20. The modality effect of ego depletion: Auditory task modality reduces ego depletion.

    PubMed

    Li, Qiong; Wang, Zhenhong

    2016-08-01

    An initial act of self-control that impairs subsequent acts of self-control is called ego depletion. The ego depletion phenomenon has been observed consistently. The modality effect refers to the effect of the presentation modality on the processing of stimuli. The modality effect was also robustly found in a large body of research. However, no study to date has examined the modality effects of ego depletion. This issue was addressed in the current study. In Experiment 1, after all participants completed a handgrip task, one group's participants completed a visual attention regulation task and the other group's participants completed an auditory attention regulation task, and then all participants again completed a handgrip task. The ego depletion phenomenon was observed in both the visual and the auditory attention regulation task. Moreover, participants who completed the visual task performed worse on the handgrip task than participants who completed the auditory task, which indicated that there was high ego depletion in the visual task condition. In Experiment 2, participants completed an initial task that either did or did not deplete self-control resources, and then they completed a second visual or auditory attention control task. The results indicated that depleted participants performed better on the auditory attention control task than the visual attention control task. These findings suggest that altering task modality may reduce ego depletion. © 2016 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

  1. Ozone depletion and chlorine loading potentials

    NASA Technical Reports Server (NTRS)

    Pyle, John A.; Wuebbles, Donald J.; Solomon, Susan; Zvenigorodsky, Sergei; Connell, Peter; Ko, Malcolm K. W.; Fisher, Donald A.; Stordal, Frode; Weisenstein, Debra

    1991-01-01

    The recognition of the roles of chlorine and bromine compounds in ozone depletion has led to the regulation or their source gases. Some source gases are expected to be more damaging to the ozone layer than others, so that scientific guidance regarding their relative impacts is needed for regulatory purposes. Parameters used for this purpose include the steady-state and time-dependent chlorine loading potential (CLP) and the ozone depletion potential (ODP). Chlorine loading potentials depend upon the estimated value and accuracy of atmospheric lifetimes and are subject to significant (approximately 20-50 percent) uncertainties for many gases. Ozone depletion potentials depend on the same factors, as well as the evaluation of the release of reactive chlorine and bromine from each source gas and corresponding ozone destruction within the stratosphere.

  2. Depletion performance of layered reservoirs without crossflow

    SciTech Connect

    Fetkovich, M.J.; Works, A.M.; Thrasher, T.S. ); Bradley, M.D. )

    1990-09-01

    This paper presents a study of the rate/time and pressure/cumulative-production depletion performance of a two-layered gas reservoir producing without crossflow. The gas reservoir has produced for more than 20 years at an effectively constant wellbore pressure, thus giving continuously declining rate/time and pressure/cumulative-production data for analysis. The field data demonstrates that Arps depletion-decline exponents between 0.5 and 1 can be obtained with a no-crossflow, layered reservoir description. Rate-vs.-time and pressure-vs.-cumulative-production predictions were developed from both 2D numerical and simplified tank models of a two layered, no-crossflow system. These results demonstrate the effects of changes in reservoir layer volumes, permeability, and skin on the depletion performance.

  3. Neutral depletion and the helicon density limit

    SciTech Connect

    Magee, R. M.; Galante, M. E.; Carr, J. Jr.; Lusk, G.; McCarren, D. W.; Scime, E. E.

    2013-12-15

    It is straightforward to create fully ionized plasmas with modest rf power in a helicon. It is difficult, however, to create plasmas with density >10{sup 20} m{sup −3}, because neutral depletion leads to a lack of fuel. In order to address this density limit, we present fast (1 MHz), time-resolved measurements of the neutral density at and downstream from the rf antenna in krypton helicon plasmas. At the start of the discharge, the neutral density underneath the antenna is reduced to 1% of its initial value in 15 μs. The ionization rate inferred from these data implies that the electron temperature near the antenna is much higher than the electron temperature measured downstream. Neutral density measurements made downstream from the antenna show much slower depletion, requiring 14 ms to decrease by a factor of 1/e. Furthermore, the downstream depletion appears to be due to neutral pumping rather than ionization.

  4. Global Warming: Lessons from Ozone Depletion

    NASA Astrophysics Data System (ADS)

    Hobson, Art

    2010-11-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of Arkansas have developed a conceptual understanding of energy and of electromagnetism, including the electromagnetic spectrum, I devote a lecture (and a textbook section) to ozone depletion and another lecture (and section) to global warming. Humankind came together in 1986 and quickly solved, to the extent that humans can solve it, ozone depletion. We could do the same with global warming, but we haven't and as yet there's no sign that we will. The parallel between the ozone and global warming cases, and the difference in outcomes, are striking and instructive.

  5. Self-regulation, ego depletion, and inhibition.

    PubMed

    Baumeister, Roy F

    2014-12-01

    Inhibition is a major form of self-regulation. As such, it depends on self-awareness and comparing oneself to standards and is also susceptible to fluctuations in willpower resources. Ego depletion is the state of reduced willpower caused by prior exertion of self-control. Ego depletion undermines inhibition both because restraints are weaker and because urges are felt more intensely than usual. Conscious inhibition of desires is a pervasive feature of everyday life and may be a requirement of life in civilized, cultural society, and in that sense it goes to the evolved core of human nature. Intentional inhibition not only restrains antisocial impulses but can also facilitate optimal performance, such as during test taking. Self-regulation and ego depletion- may also affect less intentional forms of inhibition, even chronic tendencies to inhibit. Broadly stated, inhibition is necessary for human social life and nearly all societies encourage and enforce it. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Agricultural Chartbook 1988. Agriculture Handbook No. 673.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC.

    These charts present an overview of the current economic health of American agriculture. The charts move from the national and international arenas to farm economic health measures and crop and livestock trends. A small amount of descriptive narrative accompanies most of the charts. Charts depicting the economic picture of U.S. agriculture include…

  7. 1986 Agricultural Chartbook. Agriculture Handbook No. 663.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC.

    This book contains 310 charts, tables, and graphs containing statistical information about agriculture-related commodities and services, primarily in the United States, in 1986. The book is organized in seven sections that cover the following topics: (1) the farm (farm income, farm population, farm workers, food and fiber system, agriculture and…

  8. 1986 Agricultural Chartbook. Agriculture Handbook No. 663.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC.

    This book contains 310 charts, tables, and graphs containing statistical information about agriculture-related commodities and services, primarily in the United States, in 1986. The book is organized in seven sections that cover the following topics: (1) the farm (farm income, farm population, farm workers, food and fiber system, agriculture and…

  9. Simulation of Halocarbon Production and Emissions and Effects on Ozone Depletion

    PubMed

    Holmes; Ellis

    1997-09-01

    / This paper describes an integrated model that simulates future halocarbon production/emissions and potential ozone depletion. Applications and historical production levels for various halocarbons are discussed first. A framework is then presented for modeling future halocarbon impacts incorporating differences in underlying demands, applications, regulatory mandates, and environmental characteristics. The model is used to simulate the potential impacts of several prominent issues relating to halocarbon production, regulation, and environmental interactions, notably: changes in agricultural methyl bromide use, increases in effectiveness of bromine for ozone depletion, modifications to the elimination schedule for HCFCs, short-term expansion of CFC demand in low use compliance countries, and delays in Russian Federation compliance. Individually, each issue does not unequivocally represent a significant likely increase in long-term atmospheric halogen loading and stratospheric ozone depletion. In combination, however, these impacts could increase peak halogen concentrations and long-term integral halogen loading, resulting in higher levels of stratospheric ozone depletion and longer exposure to increased levels of UV radiation.KEY WORDS: Halocarbons; Ozone depletion; Montreal Protocol; Integrated assessment

  10. Prediction of battery depletion in implanted pacemakers

    PubMed Central

    Davies, Geoffrey; Siddons, Harold

    1973-01-01

    By the use of a measuring oscilloscope and the standard electrocardiogram limb leads the degree of battery depletion in an implanted pacemaker can be estimated. A formula based on readings obtained by this means has been used to determine when Devices fixed rate pacemakers should be removed. Laboratory tests show that 90% of their useful life is obtained by this means and it proved possible to extend the period of implantation from an arbitrary 24 months to 25 to 34 months without failure from battery depletion. PMID:4731110

  11. Seasonal oxygen depletion in Chesapeake Bay

    SciTech Connect

    Taft, J.L.; Hartwig, E.O.; Loftus, R.

    1980-12-01

    The spring freshet increases density stratification in Chesapeake Bay and minimizes oxygen transfer from the surface to the deep layer so that waters below 10 m depth experience oxygen depletion which may lead to anoxia during June to September. Respiration in the water of the deep layer is the major factor contributing to oxygen depletion. Benthic respiration seems secondary. Organic matter from the previous year which has settled into the deep layer during winter provides most of the oxygen demand but some new production in the surface layer may sink and thus supplement the organic matter accumulated in the deep layer.

  12. Low Sulfur Depletion in Photodissociation Regions

    NASA Astrophysics Data System (ADS)

    Goicoechea, J. R.; Pety, J.; Gerin, M.; Teyssier, D.; Roueff, E.; Hily-Blant, P.

    2006-06-01

    Sulfur is an abundant element which remains undepleted in diffuse interstellar gas but it is historically assumed to deplete (by factors of ˜1000) on grains at higher densities. Photodissociation regions (PDRs) are an interesting intermediate medium between translucent and dark clouds where the energetics and dynamics are dominated by an illuminating FUV radiation field, and thus they can provide some new insights about the sulfur depletion problem. In this work we present our latest studies on CS and HCS^+ photochemistry, excitation and radiative transfer in the Horsehead PDR, allowing us to infer the sulfur abundance.

  13. Mineralogy as a function of depth in the prehistoric Makaopuhi tholeiitic lava lake, Hawaii

    USGS Publications Warehouse

    Evans, B.W.; Moore, J.G.

    1968-01-01

    The electron probe X-ray microanalyzer has been used to determine the compositional variability of the groundmass minerals and glass in 10 specimens from a complete 225-foot section of the prehistoric tholeiitic lava lake of Makaopuhi Crater, Hawaii. The order of beginning of crystallization was: (1) chromite, (2) olivine, (3) augite, (4) plagioclase, (5) pigeonite, (6) iron-titanium oxides and orthopyroxene, (7) alkali feldspar and apatite, and (8) glass. Although the lake is chemically tholeiitic throughout, the occurrence of ferromagnesian minerals is as though there were a gradation from alkali olivine basalt in the upper chill downwards to olivine tholeiite. Groundmass olivine decreases downwards and disappears at about 20 feet. Pigeonite is absent in the uppermost 5??2 feet, then increases in amount down to 20 feet, below which augite and pigeonite coexist in constant 2:1 proportions. Strong zoning and metastable compositions characterize the pyroxenes of the chilled zones, but these features gradually disappear towards the interior of the lake to give way to equilibrium pyroxenes. Relatively homogeneous poikilitic orthopyroxene (??? Ca4Mg70Fe26) occurs in the olivine cumulate zone, having formed partly at the expense of pre-existing olivine, augite, and pigeonite (??? Ca8Mg66Fe26). The growth of orthopyroxene is believed to have been facilitated by the slower cooling rate and higher volatile pressure at depth, and by the rise in Mg/Fe ratio of the liquid due to the partial dissolution of settled olivine. Unlike olivine and pyroxene, feldspar is least zoned in the upper and lower chilled regions. The greatest range of compositional zoning in feldspar occurs at 160 to 190 feet, where it extends continuously from Or1.0Ab22An77 to Or64Ab33An3. The feldspar fractionation trend in the An-Ab-Or triangle gradually shifts with depth toward more "equilibrium" trends, even though the zoning becomes more extreme. The variation with depth in the initial (core

  14. Sustainable agricultural water management across climates

    NASA Astrophysics Data System (ADS)

    DeVincentis, A.

    2016-12-01

    Fresh water scarcity is a global problem with local solutions. Agriculture is one of many human systems threatened by water deficits, and faces unique supply, demand, quality, and management challenges as the global climate changes and population grows. Sustainable agricultural water management is paramount to protecting global economies and ecosystems, but requires different approaches based on environmental conditions, social structures, and resource availability. This research compares water used by conservation agriculture in temperate and tropical agroecosystems through data collected from operations growing strawberries, grapes, tomatoes, and pistachios in California and corn and soybeans in Colombia. The highly manipulated hydrologic regime in California has depleted water resources and incited various adaptive management strategies, varying based on crop type and location throughout the state. Operations have to use less water more efficiently, and sometimes that means fallowing land in select groundwater basins. At the opposite end of the spectrum, the largely untouched landscape in the eastern plains of Colombia are rapidly being converted into commercial agricultural operations, with a unique opportunity to manage and plan for agricultural development with sustainability in mind. Although influenced by entirely different climates and economies, there are some similarities in agricultural water management strategies that could be applicable worldwide. Cover crops are a successful management strategy for both agricultural regimes, and moving forward it appears that farmers who work in coordination with their neighbors to plan for optimal production will be most successful in both locations. This research points to the required coordination of agricultural extension services as a critical component to sustainable water use, successful economies, and protected environments.

  15. Beyond the thrifty gene: metabolic implications of prehistoric migration into the New World.

    PubMed

    Ritenbaugh, C; Goodby, C S

    1989-06-01

    Several models have been proposed to explain the high prevalence of non-insulin dependent diabetes mellitus (NIDDM) and other diseases among New World populations. This paper examines the implications of a northern hunting adaptation (reliance on animal foods, seasonal shortages) in terms of energy digestion, absorption, metabolism and storage. Physiologic adaptations to a high protein, moderate fat, low carbohydrate diet are then examined in the context of agriculturally-based subsistence systems and in industrialized societies. Specific metabolic pathways, consistent with the work of both Neel and Weiss, are identified as fruitful areas for further research regarding genetic variants in New World populations.

  16. 48 CFR 52.223-11 - Ozone-Depleting Substances.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Ozone-Depleting Substances....223-11 Ozone-Depleting Substances. As prescribed in 23.804(a), insert the following clause: Ozone-Depleting Substances (MAY 2001) (a) Definition. Ozone-depleting substance, as used in this clause, means...

  17. 48 CFR 52.223-11 - Ozone-Depleting Substances.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 2 2013-10-01 2013-10-01 false Ozone-Depleting Substances....223-11 Ozone-Depleting Substances. As prescribed in 23.804(a), insert the following clause: Ozone-Depleting Substances (MAY 2001) (a) Definition. Ozone-depleting substance, as used in this clause, means...

  18. 48 CFR 52.223-11 - Ozone-Depleting Substances.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 2 2011-10-01 2011-10-01 false Ozone-Depleting Substances....223-11 Ozone-Depleting Substances. As prescribed in 23.804(a), insert the following clause: Ozone-Depleting Substances (MAY 2001) (a) Definition. Ozone-depleting substance, as used in this clause, means...

  19. 48 CFR 52.223-11 - Ozone-Depleting Substances.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false Ozone-Depleting Substances....223-11 Ozone-Depleting Substances. As prescribed in 23.804(a), insert the following clause: Ozone-Depleting Substances (MAY 2001) (a) Definition. Ozone-depleting substance, as used in this clause, means...

  20. 48 CFR 52.223-11 - Ozone-Depleting Substances.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 2 2012-10-01 2012-10-01 false Ozone-Depleting Substances....223-11 Ozone-Depleting Substances. As prescribed in 23.804(a), insert the following clause: Ozone-Depleting Substances (MAY 2001) (a) Definition. Ozone-depleting substance, as used in this clause, means...

  1. Temporal and Spatial Distribution of Enterobius vermicularis (Nematoda: Oxyuridae) in the Prehistoric Americas.

    PubMed

    Reinhard, Karl J; Araújo, Adauto; Morrow, Johnica J

    2016-10-01

    Investigations of Enterobius sp. infection in prehistory have produced a body of data that can be used to evaluate the geographic distribution of infection through time in the Americas. Regional variations in prevalence are evident. In North America, 119 pinworm positive samples were found in 1,112 samples from 28 sites with a prevalence of 10.7%. Almost all of the positive samples came from agricultural sites. From Brazil, 0 pinworm positive samples were found in 325 samples from 7 sites. For the Andes region, 22 pinworm positive samples were found in 411 samples from 26 sites for a prevalence of 5.3%. Detailed analyses of these data defined several trends. First, preagricultural sites less frequently show evidence of infection compared to agricultural populations. This is especially clear in the data from North America, but is also evident in the data from South America. Second, there is an apparent relationship between the commonality of pinworms in coprolites and the manner of constructing villages. These analyses show that ancient parasitism has substantial value in documenting the range of human behaviors that influence parasitic infections.

  2. Temporal and Spatial Distribution of Enterobius vermicularis (Nematoda: Oxyuridae) in the Prehistoric Americas

    PubMed Central

    Reinhard, Karl J.; Araújo, Adauto; Morrow, Johnica J.

    2016-01-01

    Investigations of Enterobius sp. infection in prehistory have produced a body of data that can be used to evaluate the geographic distribution of infection through time in the Americas. Regional variations in prevalence are evident. In North America, 119 pinworm positive samples were found in 1,112 samples from 28 sites with a prevalence of 10.7%. Almost all of the positive samples came from agricultural sites. From Brazil, 0 pinworm positive samples were found in 325 samples from 7 sites. For the Andes region, 22 pinworm positive samples were found in 411 samples from 26 sites for a prevalence of 5.3%. Detailed analyses of these data defined several trends. First, preagricultural sites less frequently show evidence of infection compared to agricultural populations. This is especially clear in the data from North America, but is also evident in the data from South America. Second, there is an apparent relationship between the commonality of pinworms in coprolites and the manner of constructing villages. These analyses show that ancient parasitism has substantial value in documenting the range of human behaviors that influence parasitic infections. PMID:27853116

  3. Impact of subjacent rocks at the water and air regime of the depleted peat deposits

    NASA Astrophysics Data System (ADS)

    Rakovich, V. A.

    2009-04-01

    At the depleted peat deposits (after peat extraction), where the residual layer of peat with the thickness of about 0,5 meters is laid at the well water permeable rocks, vegetation typical for dry conditions is developed in case of good drainage conditions; birch trees, willow, alder-trees and buckthorn prevail in this vegetation. Water and air regime is characterized here by good aeration with prevailing of oxidative processes. If water regime is regulated, these depleted peat areas are suitable for agricultural and forest lands; however, necessity of transformation of these depleted lands into forest and agricultural lands must be ecologically and economically justified. If the residual layer of peat with the thickness of 0,05-0,3 m is based at the sapropel or peat sapropel, contrast amphibiotic water and air regime with strong fluctuation of oxidative and restoration process depending on the weather conditions is formed; this regime is formed without artificial increase of the ground waters level. This does not allow bog vegetation or vegetation typical for dry conditions to develop. Thus, within 20 and more years after completion of peat extraction, such areas are not covered by vegetation in spite of favorable agro-chemical qualities of peat layer and favorable for vegetation chemical composition of soil and ground waters. Depleted peat deposits, that are based at the sapropel, are not suitable for agricultural use, because agricultural vegetation requires stable water and air regime with good aeration and oxidative and restoration potential within 400-750 mV. Contrast amphibiotic water and air regime of the depleted peat deposits that are based at sapropel excludes possibility to use them as agricultural lands. Because of this reason, areas with residual peat layer that are based at sapropel are not suitable for forest planting. Due to periodic increase of ground waters level, rot systems of the plants can not penetrate into the required depth, and mechanical

  4. Agriculture: Land Use

    EPA Pesticide Factsheets

    Land Use and agriculture. Information about land use restrictions and incentive programs.Agricultural operations sometimes involve activities regulated by laws designed to protect water supplies, threatened or endangered plants and animals, or wetlands.

  5. Traditional Agriculture and Permaculture.

    ERIC Educational Resources Information Center

    Pierce, Dick

    1997-01-01

    Discusses benefits of combining traditional agricultural techniques with the concepts of "permaculture," a framework for revitalizing traditions, culture, and spirituality. Describes school, college, and community projects that have assisted American Indian communities in revitalizing sustainable agricultural practices that incorporate…

  6. Vocational Agriculture in Ponape

    ERIC Educational Resources Information Center

    Dayrit, Ruben S.

    1975-01-01

    The general objectives of agriculture education in both the elementary and secondary schools in Ponape District are to develop interest in agriculture among students and to provide practical and technical skills in growing crops and raising domestic animals. (Author)

  7. Traditional Agriculture and Permaculture.

    ERIC Educational Resources Information Center

    Pierce, Dick

    1997-01-01

    Discusses benefits of combining traditional agricultural techniques with the concepts of "permaculture," a framework for revitalizing traditions, culture, and spirituality. Describes school, college, and community projects that have assisted American Indian communities in revitalizing sustainable agricultural practices that incorporate…

  8. Agriculture: Climate Change

    EPA Pesticide Factsheets

    Climate change affects agricultural producers because agriculture and fisheries depend on specific climate conditions. Temperature changes can cause crop planting dates to shift. Droughts and floods due to climate change may hinder farming practices.

  9. Strategies for Agriculture.

    ERIC Educational Resources Information Center

    Crosson, Pierre R.; Rosenberg, Norman J.

    1989-01-01

    Discusses the change of agricultural methods with human population growth. Describes the trends of world food production, changes in farmland, use of fertilizer, and 13 agricultural research institutions. Lists 5 references for further reading. (YP)

  10. Strategies for Agriculture.

    ERIC Educational Resources Information Center

    Crosson, Pierre R.; Rosenberg, Norman J.

    1989-01-01

    Discusses the change of agricultural methods with human population growth. Describes the trends of world food production, changes in farmland, use of fertilizer, and 13 agricultural research institutions. Lists 5 references for further reading. (YP)

  11. Direct Visualization of an Impurity Depletion Zone

    NASA Technical Reports Server (NTRS)

    Chernov, Alex A.; Garcia-Ruiz, Juan Ma; Thomas, Bill R.

    2000-01-01

    When a crystal incorporates more impurity per unit of its volume than the impurity concentration in solution, the solution in vicinity of the growing crystal is depleted with respect to the impurity I,2. With a stagnant solution, e. g. in microgravity or gels, an impurity depletion zone expands as the crystal grows and results in greater purity in most of the outer portion of the crystal than in the core. Crystallization in gel provides an opportunity to mimic microgravity conditions and visualize the impurity depletion zone. Colorless, transparent apoferritin (M congruent to 450 KDa) crystals were grown in the presence of red holoferritin dimer as a microheterogeneous impurity (M congruent to 900 KDa) within agarose gel by counterdiffusion with Cd(2+) precipitant. Preferential trapping of dimers, (distribution coefficient K = 4 (exp 1,2)) results in weaker red color around the crystals grown in the left tube in the figure as compared to the control middle tube without crystals. The left and the middle tubes contain colored ferritin dimers, the right tube contains colored trimers. The meniscus in the left tube separate gel (below) and liquid solution containing Cd(2+) (above). Similar solutions, though without precipitants, were present on top of the middle and right tube allowing diffusion of dimers and trimers. The area of weaker color intensity around crystals directly demonstrates overlapped impurity depletion zones.

  12. Global Warming: Lessons from Ozone Depletion

    ERIC Educational Resources Information Center

    Hobson, Art

    2010-01-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of…

  13. Global Warming: Lessons from Ozone Depletion

    ERIC Educational Resources Information Center

    Hobson, Art

    2010-01-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of…

  14. Kinetics of the depletion of trichloroethene

    SciTech Connect

    Barrio-Lage, G.; Parson, F.Z.; Nassar, R.S.

    1987-04-01

    The depletion of trichloroethene (TCE) was studied in microcosms containing water and three types of natural sediment ranging in composition from highly organic to a calcareous sedimentary rock. The depletion rates varied slightly in the different sediments. The first-order rate constant k/sub 1/ for the depletion of TCE ranged from 8.7 x 10/sup -4/ and 4.9 x 10/sup -4/ h/sup -1/ in soils contaminated with TCE prior to microcosm preparation to 3.4 x 10/sup -4/ and 4.6 x 10/sup -4/ h/sup -1/ for soils with a large organic content to 3.2 x 10/sup -4/ h/sup -1/ for crushed rock microcosms. Depletion was found to follow nonlinear forms of Michaelis-Menten kinetics in the organic sediments; however, microcosms containing crushed rock and water followed a linear form of the equation. K/sub m/ values were found to be dependent on the percent of total organic carbon in the sediment. 16 references, 4 figures, 2 tables.

  15. Neutral depletion versus repletion due to ionization

    SciTech Connect

    Fruchtman, A.; Makrinich, G.; Raimbault, J.-L.; Liard, L.; Rax, J.-M.; Chabert, P.

    2008-05-15

    Recent theoretical analyses which predicted unexpected effects of neutral depletion in both collisional and collisionless plasmas are reviewed. We focus on the depletion of collisionless neutrals induced by strong ionization of a collisionless plasma and contrast this depletion with the effect of strong ionization on thermalized neutrals. The collisionless plasma is analyzed employing a kinetic description. The collisionless neutrals and the plasma are coupled through volume ionization and wall recombination only. The profiles of density and pressure both of the plasma and of the neutral-gas and the profile of the ionization rate are calculated. It is shown that for collisionless neutrals the ionization results in neutral depletion, while when neutrals are thermalized the ionization induces a maximal neutral-density at the discharge center, which we call neutral repletion. The difference between the two cases stems from the relation between the neutral density and pressure. The pressure of the collisionless neutral-gas turns out to be maximal where its density is minimal, in contrast to the case of a thermalized neutral gas.

  16. Soil moisture depletion patterns around scattered trees

    Treesearch

    Robert R. Ziemer

    1968-01-01

    Soil moisture was measured around an isolated mature sugar pine tree (Pinus lambertiana Dougl.) in the mixed conifer forest type of the north central Sierra Nevada, California, from November 1965 to October 1966. From a sequence of measurements, horizontal and vertical soil moisture profiles were developed. Estimated soil moisture depletion from the 61-foot radius plot...

  17. Demonstration of jackhammer incorporating depleted uranium

    SciTech Connect

    Fischer, L E; Hoard, R W; Carter, D L; Saculla, M D; Wilson, G V

    2000-04-01

    The United States Government currently has an abundance of depleted uranium (DU). This surplus of about 1 billion pounds is the result of an enrichment process using gaseous diffusion to produce enriched and depleted uranium. The enriched uranium has been used primarily for either nuclear weapons for the military or nuclear fuel for the commercial power industry. Most of the depleted uranium remains at the enrichment process plants in the form of depleted uranium hexafluoride (DUF{sub 6}). The Department of Energy (DOE) recently began a study to identify possible commercial applications for the surplus material. One of these potential applications is to use the DU in high-density strikers/hammers in pneumatically driven tools, such as jack hammers and piledrivers to improve their impulse performance. The use of DU could potentially increase tunneling velocity and excavation into target materials with improved efficiency. This report describes the efforts undertaken to analyze the particulars of using DU in two specific striking applications: the jackhammer and chipper tool.

  18. Dissolution Treatment of Depleted Uranium Waste

    SciTech Connect

    Gates-Anderson, D D; Laue, C A; Fitch, T E

    2004-02-09

    Researchers at LLNL have developed a 3-stage process that converts pyrophoric depleted uranium metal turnings to a solidified final product that can be transported to and buried at a permitted land disposal site. The three process stages are: (1) pretreatment; (2) dissolution; and (3) solidification. Each stage was developed following extensive experimentation. This report presents the results of their experimental studies.

  19. Contrasts between Antarctic and Arctic ozone depletion.

    PubMed

    Solomon, Susan; Portmann, Robert W; Thompson, David W J

    2007-01-09

    This work surveys the depth and character of ozone depletion in the Antarctic and Arctic using available long balloon-borne and ground-based records that cover multiple decades from ground-based sites. Such data reveal changes in the range of ozone values including the extremes observed as polar air passes over the stations. Antarctic ozone observations reveal widespread and massive local depletion in the heart of the ozone "hole" region near 18 km, frequently exceeding 90%. Although some ozone losses are apparent in the Arctic during particular years, the depth of the ozone losses in the Arctic are considerably smaller, and their occurrence is far less frequent. Many Antarctic total integrated column ozone observations in spring since approximately the 1980s show values considerably below those ever observed in earlier decades. For the Arctic, there is evidence of some spring season depletion of total ozone at particular stations, but the changes are much less pronounced compared with the range of past data. Thus, the observations demonstrate that the widespread and deep ozone depletion that characterizes the Antarctic ozone hole is a unique feature on the planet.

  20. Agricultural Carbon Sinks

    NASA Astrophysics Data System (ADS)

    Horwath, W. R.; Lal, R.

    2016-12-01

    Agriculture is a source or sink of greenhouse gases depending on land use and management. Diverse activities of agroecosystems include croplands, grazing lands, forestlands, integration among these three land use systems (e.g., agroforestry, agro-pastoral, silvo-pastoral, and agro-silvo-pastoral systems), and urban and degraded lands. Conversion of natural to agroecosystems leads to decline in soil organic carbon (SOC) pool because of reduction in input of biomass-C (C­i) and increase in losses (Cl) by mineralization, erosion and leaching (Cil) through changes in micro-climate, components of the hydrologic cycle and energy budgets, and alterations in biogeochemical cycles. Historic loss from soils of agroecosystems may range from 25 to 50% in temperate regions and 50 to 75% in the tropics. The magnitude of SOC depletion is aggravated by soil degradation caused by erosion, salinization, etc. Thus, there exists a soil/ecosystem C sink which can be refilled through best management practices which create a positive C budget (Ci>Cl) and lead to recarbonization. The average rate of SOC sequestration is 0-250 kg C/ha•yr for warm and dry regions vs. 250-500 kgC/ha•yr for cool and moist climates. The potential of C sequestration is estimated at 0.4-1.2 Pg C/yr for cropland; 0.3-0.5 PgC/yr savanna and grasslands; 1.2-1.4 PgC/yr for afforestation, agroforestry, forest succession and peatlands; 0.2-0.5 PgC/yr for forest plantations; 0.3-0.7 PgC/yr for restoration of salt affected soils, and 0.2-0.7 PgC/yr for erosion and desertification control. There is an emission-avoidance by enhancing eco-efficiency of farm operations (e.g., plowing, irrigation, and input of herbicides and pesticides). These strategies are in accord with the implementation of "4 per Thousand" initiative proposed at the COP21 and COP22 Summits in Paris and Marrakech, respectively. Payments to land managers for ecosystem services, based on societal value of soil C, can promote adoption of BMPs, advance

  1. “When the going gets tough, who keeps going?” Depletion sensitivity moderates the ego-depletion effect

    PubMed Central

    Salmon, Stefanie J.; Adriaanse, Marieke A.; De Vet, Emely; Fennis, Bob M.; De Ridder, Denise T. D.

    2014-01-01

    Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In three studies, we assessed individual differences in depletion sensitivity, and demonstrate that depletion sensitivity moderates ego-depletion effects. The Depletion Sensitivity Scale (DSS) was employed to assess depletion sensitivity. Study 1 employs the DSS to demonstrate that individual differences in sensitivity to ego-depletion exist. Study 2 shows moderate correlations of depletion sensitivity with related self-control concepts, indicating that these scales measure conceptually distinct constructs. Study 3 demonstrates that depletion sensitivity moderates the ego-depletion effect. Specifically, participants who are sensitive to depletion performed worse on a second self-control task, indicating a stronger ego-depletion effect, compared to participants less sensitive to depletion. PMID:25009523

  2. Advanced agricultural biotechnologies and sustainable agriculture.

    PubMed

    Lyson, Thomas A

    2002-05-01

    Agricultural biotechnologies are anchored to a scientific paradigm rooted in experimental biology, whereas sustainable agriculture rests on a biological paradigm that is best described as ecological. Both biotechnology and sustainable agriculture are associated with particular social science paradigms: biotechnology has its foundation in neoclassical economics, but sustainability is framed by an emerging community-centered, problem-solving perspective. Fundamentally, biotechnology and neoclassical economics are reductionist in nature. Sustainability and community problem-solving, however, are nonreductionist. Given these differences, we might see the development of two rather distinct systems of food production in the near future.

  3. Information for Agricultural Development.

    ERIC Educational Resources Information Center

    Kaungamno, E. E.

    This paper describes the major international agricultural information services, sources, and systems; outlines the existing information situation in Tanzania as it relates to problems of agricultural development; and reviews the improvements in information provision resources required to support the process of agricultural development in Tanzania.…

  4. African Americans and Agriculture.

    ERIC Educational Resources Information Center

    Morgan, Joan

    2000-01-01

    Reviews the opportunities available in the field of agriculture for African American students and notes efforts of the 136 colleges of agriculture to publicize their offerings and recruit students. Profiles six black leaders in agriculture, highlighting their achievements in research and aid to developing countries. A table provides data on annual…

  5. Agricultural Structures, Volume II.

    ERIC Educational Resources Information Center

    Linhardt, Richard E.; Burhoe, Steve

    This guide to a curriculum unit in agricultural structures is designed to expand the curriculum materials available in vocational agriculture in Missouri. It and Agricultural Structures I (see note) provide reference materials to systematize the curriculum. The six units cover working with concrete (19 lessons, 2 laboratory exercises), drawing and…

  6. Biotechnology and Agriculture.

    ERIC Educational Resources Information Center

    Kenney, Martin

    Even at this early date in the application of biotechnology to agriculture, it is clear that agriculture may provide the largest market for new or less expensive biotechnologically manufactured products. The chemical and pharmaceutical industries that hold important positions in agricultural inputs are consolidating their positions by purchasing…

  7. Agriculture Business and Management.

    ERIC Educational Resources Information Center

    Seperich, George; And Others

    This curriculum guide is intended for vocational agriculture teachers who deliver agricultural business and management programs at the secondary or postsecondary level. It is based on the Arizona validated occupational competencies and tasks for management and supervisory positions in agricultural business. The competency/skill and task list…

  8. Chapter 3: Cropland Agriculture

    USDA-ARS?s Scientific Manuscript database

    In 2013, cropland agriculture resulted in total emissions of approximately 209 MMT CO2 eq. of greenhouse gases (GHG). Cropland agriculture is responsible for almost half (46%) of all emissions from the agricultural sector. Nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4) emissions from c...

  9. Agricultural Structures, Volume II.

    ERIC Educational Resources Information Center

    Linhardt, Richard E.; Burhoe, Steve

    This guide to a curriculum unit in agricultural structures is designed to expand the curriculum materials available in vocational agriculture in Missouri. It and Agricultural Structures I (see note) provide reference materials to systematize the curriculum. The six units cover working with concrete (19 lessons, 2 laboratory exercises), drawing and…

  10. Agriculture, Environmental Education Guide.

    ERIC Educational Resources Information Center

    Project I-C-E, Green Bay, WI.

    This agriculture guide, for use at the secondary level, is one of a series of guides, K-12, which were developed by teachers to help introduce environmental education into the total curriculum. Environmental problems are present in every community where agriculture education is offered, and therefore many agriculture teachers have included some…

  11. Dutch Agricultural Education.

    ERIC Educational Resources Information Center

    Netherlands Ministry of Agriculture and Fisheries, The Hauge.

    Agricultural Education in the Netherlands is categorized as Scientific, Higher Secondary, Middle Secondary, and Lower Secondary. Scientific education is given at the agricultural university which has a 6- or 7-year curriculum. Higher secondary education is given at agricultural and horticultural colleges with a 3- to 4-year curriculum. Middle…

  12. Agriculture Business and Management.

    ERIC Educational Resources Information Center

    Seperich, George; And Others

    This curriculum guide is intended for vocational agriculture teachers who deliver agricultural business and management programs at the secondary or postsecondary level. It is based on the Arizona validated occupational competencies and tasks for management and supervisory positions in agricultural business. The competency/skill and task list…

  13. How Depleted is the MORB mantle?

    NASA Astrophysics Data System (ADS)

    Hofmann, A. W.; Hart, S. R.

    2015-12-01

    Knowledge of the degree of mantle depletion of highly incompatible elements is critically important for assessing Earth's internal heat production and Urey number. Current views of the degree of MORB source depletion are dominated by Salters and Stracke (2004), and Workman and Hart (2005). The first is based on an assessment of average MORB compositions, whereas the second considers trace element data of oceanic peridotites. Both require an independent determination of one absolute concentration, Lu (Salters & Stracke), or Nd (Workman & Hart). Both use parent-daughter ratios Lu/Hf, Sm/Nd, and Rb/Sr calculated from MORB isotopes combined with continental-crust extraction models, as well as "canonical" trace element ratios, to boot-strap the full range of trace element abundances. We show that the single most important factor in determining the ultimate degree of incompatible element depletion in the MORB source lies in the assumptions about the timing of continent extraction, exemplified by continuous extraction versus simple two-stage models. Continued crust extraction generates additional, recent mantle depletion, without affecting the isotopic composition of the residual mantle significantly. Previous emphasis on chemical compositions of MORB and/or peridotites has tended to obscure this. We will explore the effect of different continent extraction models on the degree of U, Th, and K depletion in the MORB source. Given the uncertainties of the two most popular models, the uncertainties of U and Th in DMM are at least ±50%, and this impacts the constraints on the terrestrial Urey ratio. Salters, F.J.M. and Stracke, A., 2004, Geochem. Geophys. Geosyst. 5, Q05004. Workman, R.K. and Hart, S.R., 2005, EPSL 231, 53-72.

  14. High dietary intake of prebiotic inulin-type fructans in the prehistoric Chihuahuan Desert.

    PubMed

    Leach, Jeff D; Sobolik, Kristin D

    2010-06-01

    Archaeological evidence from dry cave deposits in the northern Chihuahuan Desert reveal intensive utilisation of desert plants that store prebiotic inulin-type fructans as the primary carbohydrate. In this semi-arid region limited rainfall and poor soil conditions prevented the adoption of agriculture and thus provides a unique glimpse into a pure hunter-forager economy spanning over 10 000 years. Ancient cooking features, stable carbon isotope analysis of human skeletons, and well-preserved coprolites and macrobotanical remains reveal a plant-based diet that included a dietary intake of about 135 g prebiotic inulin-type fructans per d by the average adult male hunter-forager. These data reveal that man is well adapted to daily intakes of prebiotics well above those currently consumed in the modern diet.

  15. Using Stochastically Downscaled Climate Models and Multiproxy Lake Sediment Data to Connect Climatic Variations Over the Past 1000 Years and the History of Prehistoric Maize Farming in Utah

    NASA Astrophysics Data System (ADS)

    Thomson, M. J.; MacDonald, G. M.

    2015-12-01

    We are investigating the relationship between climatic variations over the past 1000 years and the history of prehistoric maize farming expansion and decline in the American Southwest, with a focus on Utah. We are examining both the downscaled climate models and high resolution analyses of lake cores and dendrochronological data matched with occupation information. We are testing the specific utility of stochastically downscaled general circulation models (viz. ECHO-G) to reconstruct local conditions for sites with documented prehistoric dryland farming through the so-called Medieval Climate Anomaly (MCA) and transition to the Little Ice Age (LIA). We are testing our model-based reconstructions with proxies of temperature and aridity from three subalpine lake sediment cores transecting Utah. We compare the patterns of climate change from the downscaled models and the paleoclimate records to a database of 837 radiocarbon dates over 169 locations of archaeological Native American maize-farmer site occupations in Utah.

  16. A Programmatic Approach to Determine Eligibility of Prehistoric Sites in the San Diego Subregion, Southern Coast Archeological Region, California, for the National Register of Historic Places

    DTIC Science & Technology

    2007-08-01

    recovered from the island was obtained from eastern California , particularly from Coso Volcanic Field (Rick et al. 2001). Obsidian hydration , however, has...1981 Exchange and Production Systems in California Prehistory: The Results of Hydration Dating and Chemical Characterization of Obsidian Sources. BAR...Sea-Level Curves for Santa Monica Shelf, California Continental Borderland . Science 213:331–333. Noah, Anna 1998 Prehistoric Fishing on the San Diego

  17. External ear canal exostosis and otitis media in temporal bones of prehistoric and historic chilean populations. A paleopathological and paleoepidemiological study.

    PubMed

    Castro, Mario; Goycoolea, Marcos; Silva-Pinto, Verónica

    2017-04-01

    External ear canal exostosis is more prevalent in northern coastal groups than in the highlands, suggesting that ocean activities facilitate the appearance of exostosis. However, southern coastal groups exposed to colder ocean water have a lesser incidence of exostosis, possibly due to less duration of exposure. There was a high incidence of otitis media in all groups of native population in Chile. One coastal group had a higher incidence, presumably due to racial factors. This is a paleopathological and paleoepidemiological study in temporal bones which assesses external ear canal exostosis and otitis media in prehistoric and historic native populations in Chile. A total of 460 temporal bones were evaluated for exostosis (ex) and 542 temporal bones were evaluated for otitis media (om). The study involved four groups: (1) Prehistoric Coastal (400-1000 AD) populations in Northern Chile (Pisagua-Tiwanaku) (22 temporal bones ex; 28 om); (2) Prehistoric Highland (400-1000 AD) populations in Northern Chile (292 temporal bones ex; 334 om); (3) Pisagua-Regional Developments (coastal) in Northern Chile (1000-1450 AD) (66 temporal bones ex; 82 om); and (4) Historic (1500-1800 AD) coastal populations in Southern Chile (80 temporal bones ex: 18 Chonos, 62 Fuegians. 98 om: 22 Chonos, 76 Fuegians). Skulls were evaluated visually and with an operating microscope. In addition, the otitis media group was evaluated with Temporal bone radiology - -lateral XRays-Schuller view - to assess pneumatization as evidence of previous middle ear disease. Prehistoric northern coastal groups had an incidence of exostosis of 15.91%, the northern highlands group 1.37%, and the southern coastal group 1.25%. There were changes suggestive of otitis media in: Pisagua/Tiwanaku 53.57%; Pisagua/Regional Developments 70.73%; Northern Highlands population 47.90%; Chonos 63.64%; and Fuegian tribes 64.47%.

  18. Iron isotope composition of depleted MORB

    NASA Astrophysics Data System (ADS)

    Labidi, J.; Sio, C. K. I.; Shahar, A.

    2015-12-01

    In terrestrial basalts, iron isotope ratios are observed to weakly fractionate as a function of olivine and pyroxene crystallization. However, a ~0.1‰ difference between chondrites and MORB had been reported (Dauphas et al. 2009, Teng et al. 2013 and ref. therein). This observation could illustrate an isotope fractionation occurring during partial melting, as a function of the Fe valence in melt versus crystals. Here, we present high-precision Fe isotopic data measured by MC-ICP-MS on well-characterized samples from the Pacific-Antarctic Ridge (PAR, n=9) and from the Garrett Transform Fault (n=8). These samples allow exploring the Fe isotope fractionation between melt and magnetite, and the role of partial melting on Fe isotope fractionation. Our average δ56Fe value is +0.095±0.013‰ (95% confidence, n=17), indistinguishable from a previous estimate of +0.105±0.006‰ (95% confidence, n=43, see ref. 2). Our δ56Fe values correlate weakly with MgO contents, and correlate positively with K/Ti ratios. PAC1 DR10 shows the largest Ti and Fe depletion after titanomagnetite fractionation, with a δ56Fe value of +0.076±0.036‰. This is ~0.05‰ below other samples at a given MgO. This may illustrate a significant Fe isotope fractionation between the melt and titanomagnetite, in agreement with experimental determination (Shahar et al. 2008). GN09-02, the most incompatible-element depleted sample, has a δ56Fe value of 0.037±0.020‰. This is the lowest high-precision δ56Fe value recorded for a MORB worldwide. This basalt displays an incompatible-element depletion consistent with re-melting beneath the transform fault of mantle source that was depleted during a first melting event, beneath the ridge axis (Wendt et al. 1999). The Fe isotope observation could indicate that its mantle source underwent 56Fe depletion after a first melting event. It could alternatively indicate a lower Fe isotope fractionation during re-melting, if the source was depleted of its Fe3

  19. First use of portable system coupling X-ray diffraction and X-ray fluorescence for in-situ analysis of prehistoric rock art.

    PubMed

    Beck, L; Rousselière, H; Castaing, J; Duran, A; Lebon, M; Moignard, B; Plassard, F

    2014-11-01

    Study of prehistoric art is playing a major role in the knowledge of human evolution. Many scientific methods are involved in this investigation including chemical analysis of pigments present on artefacts or applied to cave walls. In the past decades, the characterization of coloured materials was carried on by taking small samples. This procedure had two main disadvantages: slight but existing damage of the paintings and limitation of the number of samples. Thanks to the advanced development of portable systems, in-situ analysis of pigment in cave can be now undertaken without fear for this fragile Cultural Heritage. For the first time, a portable system combining XRD and XRF was used in an underground and archaeological environment for prehistoric rock art studies. In-situ non-destructive analysis of black prehistoric drawings and determination of their composition and crystalline structure were successfully carried out. Original results on pigments used 13,000 years ago in the cave of Rouffignac (France) were obtained showing the use of two main manganese oxides: pyrolusite and romanechite. The capabilities of the portable XRD-XRF system have been demonstrated for the characterization of pigments as well as for the analysis of rock in a cave environment. This first in-situ experiment combining X-ray diffraction and X-ray fluorescence open up new horizons and can fundamentally change our approach of rock art studies.

  20. East, West, North, South: A look at a method available to prehistoric cultures to both determine cardinality and the date of the equinox

    NASA Astrophysics Data System (ADS)

    Hull, Anthony B.; Ambruster, C.; Jewell, E.

    2014-01-01

    Many prehistoric world cultures have public and sacred buildings and roads which may exhibit cardinality (alignment to the true cardinal directions) to impressive precision. Careful alignment of such buildings would seem a means to relate the ground hemisphere to the celestial hemisphere. Not all prehistoric cultures cared about true cardinality, but apparently many did. Even today, lacking surveying instruments or GPS, determination of the cardinal directions, even to ±1-2 degrees, is challenging. In this paper we examine how these directions could have been accurately determined by prehistoric peoples with attentive observation using simply a gnomon. While we will not examine here their models of the cosmos, nor why they would construct to these alignments, we do examine expected systematic and random errors in such determinations if a gnomon is used. Our models demonstrate that marking the shadow locus from a gnomon not only can inform on cardinality to remarkable precision, but also is capable of giving the date of equinox to perhaps ±1-2days

  1. Copenhagen delegates advance phaseout of ozone depleters

    SciTech Connect

    Kirschner, E.

    1992-12-09

    As expected, delegates at the United Nations Ozone Layer Conference in Copenhagen sped up ozone depleter phaseouts from the 1987 Montreal Protocol and the 1990 London amendments. The changes bring the worldwide production phaseout of chlorofluorocarbons (CFCs) and other ozone depleters in developed countries in line with U.S. and European plans announced earlier this year. Adjustments to the protocol, which are binding on the signatories, change the phaseout for CFC, carbon tetrachloride, and methyl chloroform production and consumption to January 1, 1996 from 2000. The 75% reduction of 1986 levels from CFCs by January 1, 1994 is a compromise between European pressure for an 85% cut and the US goal of 70%. Halon production is to end January 1, 1994, as anticipated. Developing countries continue to have a 10-year grace period. Friends of the Earth ozone campaign director Liz Cook counters that the phaseout dates were scheduled with concern for the chemical industry, not for the ozone layer.

  2. Replacements For Ozone-Depleting Foaming Agents

    NASA Technical Reports Server (NTRS)

    Blevins, Elana; Sharpe, Jon B.

    1995-01-01

    Fluorinated ethers used in place of chlorofluorocarbons and hydrochlorofluorocarbons. Replacement necessary because CFC's and HCFC's found to contribute to depletion of ozone from upper atmosphere, and manufacture and use of them by law phased out in near future. Two fluorinated ethers do not have ozone-depletion potential and used in existing foam-producing equipment, designed to handle liquid blowing agents soluble in chemical ingredients that mixed to make foam. Any polyurethane-based foams and several cellular plastics blown with these fluorinated ethers used in processes as diverse as small batch pours, large sprays, or double-band lamination to make insulation for private homes, commercial buildings, shipping containers, and storage tanks. Fluorinated ethers proved useful as replacements for CFC refrigerants and solvents.

  3. Replacements For Ozone-Depleting Foaming Agents

    NASA Technical Reports Server (NTRS)

    Blevins, Elana; Sharpe, Jon B.

    1995-01-01

    Fluorinated ethers used in place of chlorofluorocarbons and hydrochlorofluorocarbons. Replacement necessary because CFC's and HCFC's found to contribute to depletion of ozone from upper atmosphere, and manufacture and use of them by law phased out in near future. Two fluorinated ethers do not have ozone-depletion potential and used in existing foam-producing equipment, designed to handle liquid blowing agents soluble in chemical ingredients that mixed to make foam. Any polyurethane-based foams and several cellular plastics blown with these fluorinated ethers used in processes as diverse as small batch pours, large sprays, or double-band lamination to make insulation for private homes, commercial buildings, shipping containers, and storage tanks. Fluorinated ethers proved useful as replacements for CFC refrigerants and solvents.

  4. Ozone depletion in tropospheric volcanic plumes

    NASA Astrophysics Data System (ADS)

    Vance, Alan; McGonigle, Andrew J. S.; Aiuppa, Alessandro; Stith, Jeffrey L.; Turnbull, Kate; von Glasow, Roland

    2010-11-01

    We measured ozone (O3) concentrations in the atmospheric plumes of the volcanoes St. Augustine (1976), Mt. Etna (2004, 2009) and Eyjafjallajökull (2010) and found O3 to be strongly depleted compared to the background at each volcano. At Mt. Etna O3 was depleted within tens of seconds from the crater, the age of the St. Augustine plumes was on the order of hours, whereas the O3 destruction in the plume of Eyjafjallajökull was maintained in 1-9 day old plumes. The most likely cause for this O3 destruction are catalytic bromine reactions as suggested by a model that manages to reproduce the very early destruction of O3 but also shows that O3 destruction is ongoing for several days. Given the observed rapid and sustained destruction of O3, heterogeneous loss of O3 on ash is unlikely to be important.

  5. Endoplasmic-Reticulum Calcium Depletion and Disease

    PubMed Central

    Mekahli, Djalila; Bultynck, Geert; Parys, Jan B.; De Smedt, Humbert; Missiaen, Ludwig

    2011-01-01

    The endoplasmic reticulum (ER) as an intracellular Ca2+ store not only sets up cytosolic Ca2+ signals, but, among other functions, also assembles and folds newly synthesized proteins. Alterations in ER homeostasis, including severe Ca2+ depletion, are an upstream event in the pathophysiology of many diseases. On the one hand, insufficient release of activator Ca2+ may no longer sustain essential cell functions. On the other hand, loss of luminal Ca2+ causes ER stress and activates an unfolded protein response, which, depending on the duration and severity of the stress, can reestablish normal ER function or lead to cell death. We will review these various diseases by mainly focusing on the mechanisms that cause ER Ca2+ depletion. PMID:21441595

  6. Assessment of Preferred Depleted Uranium Disposal Forms

    SciTech Connect

    Croff, A.G.; Hightower, J.R.; Lee, D.W.; Michaels, G.E.; Ranek, N.L.; Trabalka, J.R.

    2000-06-01

    The Department of Energy (DOE) is in the process of converting about 700,000 metric tons (MT) of depleted uranium hexafluoride (DUF6) containing 475,000 MT of depleted uranium (DU) to a stable form more suitable for long-term storage or disposal. Potential conversion forms include the tetrafluoride (DUF4), oxide (DUO2 or DU3O8), or metal. If worthwhile beneficial uses cannot be found for the DU product form, it will be sent to an appropriate site for disposal. The DU products are considered to be low-level waste (LLW) under both DOE orders and Nuclear Regulatory Commission (NRC) regulations. The objective of this study was to assess the acceptability of the potential DU conversion products at potential LLW disposal sites to provide a basis for DOE decisions on the preferred DU product form and a path forward that will ensure reliable and efficient disposal.

  7. Depleted uranium plasma reduction system study

    SciTech Connect

    Rekemeyer, P.; Feizollahi, F.; Quapp, W.J.; Brown, B.W.

    1994-12-01

    A system life-cycle cost study was conducted of a preliminary design concept for a plasma reduction process for converting depleted uranium to uranium metal and anhydrous HF. The plasma-based process is expected to offer significant economic and environmental advantages over present technology. Depleted Uranium is currently stored in the form of solid UF{sub 6}, of which approximately 575,000 metric tons is stored at three locations in the U.S. The proposed system is preconceptual in nature, but includes all necessary processing equipment and facilities to perform the process. The study has identified total processing cost of approximately $3.00/kg of UF{sub 6} processed. Based on the results of this study, the development of a laboratory-scale system (1 kg/h throughput of UF6) is warranted. Further scaling of the process to pilot scale will be determined after laboratory testing is complete.

  8. Streamflow depletion by wells--Understanding and managing the effects of groundwater pumping on streamflow

    USGS Publications Warehouse

    Barlow, Paul M.; Leake, Stanley A.

    2012-11-02

    Groundwater is an important source of water for many human needs, including public supply, agriculture, and industry. With the development of any natural resource, however, adverse consequences may be associated with its use. One of the primary concerns related to the development of groundwater resources is the effect of groundwater pumping on streamflow. Groundwater and surface-water systems are connected, and groundwater discharge is often a substantial component of the total flow of a stream. Groundwater pumping reduces the amount of groundwater that flows to streams and, in some cases, can draw streamflow into the underlying groundwater system. Streamflow reductions (or depletions) caused by pumping have become an important water-resource management issue because of the negative impacts that reduced flows can have on aquatic ecosystems, the availability of surface water, and the quality and aesthetic value of streams and rivers. Scientific research over the past seven decades has made important contributions to the basic understanding of the processes and factors that affect streamflow depletion by wells. Moreover, advances in methods for simulating groundwater systems with computer models provide powerful tools for estimating the rates, locations, and timing of streamflow depletion in response to groundwater pumping and for evaluating alternative approaches for managing streamflow depletion. The primary objective of this report is to summarize these scientific insights and to describe the various field methods and modeling approaches that can be used to understand and manage streamflow depletion. A secondary objective is to highlight several misconceptions concerning streamflow depletion and to explain why these misconceptions are incorrect.

  9. The ultimate disposition of depleted uranium

    SciTech Connect

    Not Available

    1990-12-01

    Significant amounts of the depleted uranium (DU) created by past uranium enrichment activities have been sold, disposed of commercially, or utilized by defense programs. In recent years, however, the demand for DU has become quite small compared to quantities available, and within the US Department of Energy (DOE) there is concern for any risks and/or cost liabilities that might be associated with the ever-growing inventory of this material. As a result, Martin Marietta Energy Systems, Inc. (Energy Systems), was asked to review options and to develop a comprehensive plan for inventory management and the ultimate disposition of DU accumulated at the gaseous diffusion plants (GDPs). An Energy Systems task team, under the chairmanship of T. R. Lemons, was formed in late 1989 to provide advice and guidance for this task. This report reviews options and recommends actions and objectives in the management of working inventories of partially depleted feed (PDF) materials and for the ultimate disposition of fully depleted uranium (FDU). Actions that should be considered are as follows. (1) Inspect UF{sub 6} cylinders on a semiannual basis. (2) Upgrade cylinder maintenance and storage yards. (3) Convert FDU to U{sub 3}O{sub 8} for long-term storage or disposal. This will include provisions for partial recovery of costs to offset those associated with DU inventory management and the ultimate disposal of FDU. Another recommendation is to drop the term tails'' in favor of depleted uranium'' or DU'' because the tails'' label implies that it is waste.'' 13 refs.

  10. Health Effects of Embedded Depleted Uranium Fragments.

    DTIC Science & Technology

    2011-03-24

    Canada Feasibility Studies of a Method for Determining Depleted Uranium Deposited in Human Limbs .................. 39 Gary S . Kramer and Erin S . Niven...International Defense Review, 27:39-46 4 Introduction to the Problem 11. Filszar RL, Wilsey EF, Bloore EW (1989) Ra- and bulk storage conditions. Richland, WA...MD, Report BRL-TR- 3068 19. Limits for intakes of radionuclides by workers (1981) Pergamon Press, N.Y., ICRP Publication 12. Wilsey EF, Bloore EW (1989

  11. Carbon sequestration in depleted oil shale deposits

    DOEpatents

    Burnham, Alan K; Carroll, Susan A

    2014-12-02

    A method and apparatus are described for sequestering carbon dioxide underground by mineralizing the carbon dioxide with coinjected fluids and minerals remaining from the extraction shale oil. In one embodiment, the oil shale of an illite-rich oil shale is heated to pyrolyze the shale underground, and carbon dioxide is provided to the remaining depleted oil shale while at an elevated temperature. Conditions are sufficient to mineralize the carbon dioxide.

  12. The ultimate disposition of depleted uranium

    SciTech Connect

    Lemons, T.R.

    1991-12-31

    Depleted uranium (DU) is produced as a by-product of the uranium enrichment process. Over 340,000 MTU of DU in the form of UF{sub 6} have been accumulated at the US government gaseous diffusion plants and the stockpile continues to grow. An overview of issues and objectives associated with the inventory management and the ultimate disposition of this material is presented.

  13. Depletion modeling of liquid dominated geothermal reservoirs

    SciTech Connect

    Olsen, G.

    1984-06-01

    Depletion models for liquid-dominated geothermal reservoirs are derived and presented. The depletion models are divided into two categories: confined and unconfined. For both cases depletion models with no recharge (or influx), and depletion models including recharge, are used to match field data from the Svartsengi high temperature geothermal field in Iceland. The influx models included with the mass and energy balances are adopted from the petroleum engineering literature. The match to production data from Svartsengi is improved when influx was included. The Schilthuis steady-state influx gives a satisfactory match. The finite aquifer method of Fetkovitch, and the unsteady state method of Hurst gave reasonable answers, but not as good. The best match is obtained using Hurst simplified solution when lambda = 1.3 x 10{sup -4} m{sup -1}. From the match the cross-sectional area of the aquifer was calculated as 3.6 km{sup 2}. The drawdown was predicted using the Hurst simplified method, and compared with predicted drawdown from a boiling model and an empirical log-log model. A large difference between the models was obtained. The predicted drawdown using the Hurst simplified method falls between the other two. Injection has been considered by defining the net rate as being the production rate minus the injection rate. No thermal of transient effects were taken into account. Prediction using three different net rates shows that the pressure can be maintained using the Hurst simplified method if there is significant fluid reinjection. 32 refs., 44 figs., 2 tabs.

  14. Barium depletion in hollow cathode emitters

    NASA Astrophysics Data System (ADS)

    Polk, James E.; Mikellides, Ioannis G.; Capece, Angela M.; Katz, Ira

    2016-01-01

    Dispenser hollow cathodes rely on a consumable supply of Ba released by BaO-CaO-Al2O3 source material in the pores of a tungsten matrix to maintain a low work function surface. The examination of cathode emitters from long duration tests shows deposits of tungsten at the downstream end that appear to block the flow of Ba from the interior. In addition, a numerical model of Ba transport in the cathode plasma indicates that the Ba partial pressure in the insert may exceed the equilibrium vapor pressure of the dominant Ba-producing reaction, and it was postulated previously that this would suppress Ba loss in the upstream part of the emitter. New measurements of the Ba depletion depth from a cathode insert operated for 8200 h reveal that Ba loss is confined to a narrow region near the downstream end, confirming this hypothesis. The Ba transport model was modified to predict the depletion depth with time. A comparison of the calculated and measured depletion depths gives excellent qualitative agreement, and quantitative agreement was obtained assuming an insert temperature 70 °C lower than measured beginning-of-life values.

  15. Renal cortical pyruvate depletion during AKI.

    PubMed

    Zager, Richard A; Johnson, Ali C M; Becker, Kirsten

    2014-05-01

    Pyruvate is a key intermediary in energy metabolism and can exert antioxidant and anti-inflammatory effects. However, the fate of pyruvate during AKI remains unknown. Here, we assessed renal cortical pyruvate and its major determinants (glycolysis, gluconeogenesis, pyruvate dehydrogenase [PDH], and H2O2 levels) in mice subjected to unilateral ischemia (15-60 minutes; 0-18 hours of vascular reflow) or glycerol-induced ARF. The fate of postischemic lactate, which can be converted back to pyruvate by lactate dehydrogenase, was also addressed. Ischemia and glycerol each induced persistent pyruvate depletion. During ischemia, decreasing pyruvate levels correlated with increasing lactate levels. During early reperfusion, pyruvate levels remained depressed, but lactate levels fell below control levels, likely as a result of rapid renal lactate efflux. During late reperfusion and glycerol-induced AKI, pyruvate depletion corresponded with increased gluconeogenesis (pyruvate consumption). This finding was underscored by observations that pyruvate injection increased renal cortical glucose content in AKI but not normal kidneys. AKI decreased PDH levels, potentially limiting pyruvate to acetyl CoA conversion. Notably, pyruvate therapy mitigated the severity of AKI. This renoprotection corresponded with increases in cytoprotective heme oxygenase 1 and IL-10 mRNAs, selective reductions in proinflammatory mRNAs (e.g., MCP-1 and TNF-α), and improved tissue ATP levels. Paradoxically, pyruvate increased cortical H2O2 levels. We conclude that AKI induces a profound and persistent depletion of renal cortical pyruvate, which may induce additional injury.

  16. Barium depletion in hollow cathode emitters

    SciTech Connect

    Polk, James E. Mikellides, Ioannis G.; Katz, Ira; Capece, Angela M.

    2016-01-14

    Dispenser hollow cathodes rely on a consumable supply of Ba released by BaO-CaO-Al{sub 2}O{sub 3} source material in the pores of a tungsten matrix to maintain a low work function surface. The examination of cathode emitters from long duration tests shows deposits of tungsten at the downstream end that appear to block the flow of Ba from the interior. In addition, a numerical model of Ba transport in the cathode plasma indicates that the Ba partial pressure in the insert may exceed the equilibrium vapor pressure of the dominant Ba-producing reaction, and it was postulated previously that this would suppress Ba loss in the upstream part of the emitter. New measurements of the Ba depletion depth from a cathode insert operated for 8200 h reveal that Ba loss is confined to a narrow region near the downstream end, confirming this hypothesis. The Ba transport model was modified to predict the depletion depth with time. A comparison of the calculated and measured depletion depths gives excellent qualitative agreement, and quantitative agreement was obtained assuming an insert temperature 70 °C lower than measured beginning-of-life values.

  17. Pumping test evaluation of stream depletion parameters.

    PubMed

    Lough, Hilary K; Hunt, Bruce

    2006-01-01

    Descriptions are given of a pumping test and a corresponding analysis that permit calculation of all five hydrogeological parameters appearing in the Hunt (2003) solution for stream depletion caused by ground water abstraction from a well beside a stream. This solution assumes that flow in the pumped aquifer is horizontal, flow in the overlying aquitard or system of aquitards is vertical, and the free surface in the top aquitard is allowed to draw down. The definition of an aquitard in this paper is any layer with a vertical hydraulic conductivity much lower than the horizontal hydraulic conductivity of the pumped aquifer. These "aquitards" may be reasonably permeable layers but are distinguished from the pumped aquifer by their hydraulic conductivity contrast. The pumping test requires a complete set of drawdown measurements from at least one observation well. This well must be deep enough to penetrate the pumped aquifer, and pumping must continue for a sufficient time to ensure that depleted streamflow becomes a significant portion of the well abstraction rate. Furthermore, two of the five parameters characterize an aquitard that overlies the pumped aquifer, and values for these parameters are seen to be dependent upon the initial water table elevation in the aquitard. The field test analyzed herein used a total of eight observation wells screened in the pumped aquifer, and measurements from these wells gave eight sets of parameters that are used in a sensitivity analysis to determine the relative importance of each parameter in the stream depletion calculations.

  18. Understanding the haling power depletion (HPD) method

    SciTech Connect

    Levine, S.; Blyth, T.; Ivanov, K.

    2012-07-01

    The Pennsylvania State Univ. (PSU) is using the university version of the Studsvik Scandpower Code System (CMS) for research and education purposes. Preparations have been made to incorporate the CMS into the PSU Nuclear Engineering graduate class 'Nuclear Fuel Management' course. The information presented in this paper was developed during the preparation of the material for the course. The Haling Power Depletion (HPD) was presented in the course for the first time. The HPD method has been criticized as not valid by many in the field even though it has been successfully applied at PSU for the past 20 years. It was noticed that the radial power distribution (RPD) for low leakage cores during depletion remained similar to that of the HPD during most of the cycle. Thus, the Haling Power Depletion (HPD) may be used conveniently mainly for low leakage cores. Studies were then made to better understand the HPD and the results are presented in this paper. Many different core configurations can be computed quickly with the HPD without using Burnable Poisons (BP) to produce several excellent low leakage core configurations that are viable for power production. Once the HPD core configuration is chosen for further analysis, techniques are available for establishing the BP design to prevent violating any of the safety constraints in such HPD calculated cores. In summary, in this paper it has been shown that the HPD method can be used for guiding the design for the low leakage core. (authors)

  19. Development and application of methods used to source prehistoric Southwestern maize: a review

    USGS Publications Warehouse

    Benson, Larry V.

    2012-01-01

    Archaeological cobs free of mineral contaminants should be used to source the soils in which they were grown. Mineral contaminants often contain much higher concentrations of metals than vegetal materials and can alter a cob’s apparent metal and heavy-isotope content. Cleaning a cob via immersion in an acid solution for more than a few minutes will result in the incongruent and sometimes complete leaching of metals, including strontium (Sr), from the cob. When using 87Sr/Sr to determine the location of potential agriculture fields, it is best to either integrate several depth-integrated soil samples or to integrate several vegetation samples from individual fields. Biologically labile Sr in semi-arid Southwestern soils largely originates from eolian source or sources and usually is not derived from underlying bedrock. Existing Sr-isotope data indicate that archaeological cobs from Aztec Ruins came from either the Mesa Verde-McElmo Dome or Totah areas, that Pueblo Bonito and Chetro Ketl cobs, from Chaco Canyon that predate A.D. 1130, probably came from the Rio Chaco corridor, and that cobs from Chaco Canyon, that postdate A.D. 1130, probably came from either the Totah or Zuni areas.

  20. High frequency of lactose intolerance in a prehistoric hunter-gatherer population in northern Europe.

    PubMed

    Malmström, Helena; Linderholm, Anna; Lidén, Kerstin; Storå, Jan; Molnar, Petra; Holmlund, Gunilla; Jakobsson, Mattias; Götherström, Anders

    2010-03-30

    Genes and culture are believed to interact, but it has been difficult to find direct evidence for the process. One candidate example that has been put forward is lactase persistence in adulthood, i.e. the ability to continue digesting the milk sugar lactose after childhood, facilitating the consumption of raw milk. This genetic trait is believed to have evolved within a short time period and to be related with the emergence of sedentary agriculture. Here we investigate the frequency of an allele (-13910*T) associated with lactase persistence in a Neolithic Scandinavian population. From the 14 individuals originally examined, 10 yielded reliable results. We find that the T allele frequency was very low (5%) in this Middle Neolithic hunter-gatherer population, and that the frequency is dramatically different from the extant Swedish population (74%). We conclude that this difference in frequency could not have arisen by genetic drift and is either due to selection or, more likely, replacement of hunter-gatherer populations by sedentary agriculturalists.

  1. Prehistoric Human Adaptation to Tibetan Plateau Environment indicated by 151 site in the Qinghai Lake Basin

    NASA Astrophysics Data System (ADS)

    Zhang, Dongju; Dong, Guanghui; Wang, Qianqian; Ren, Xiaoyan; Chen, Fahu

    2017-04-01

    Current study indicates that Northeastern Tibetan Plateau (NETP) is one of the first widely occupied places by prehistory people on the Tibetan Plateau, which makes NETP very important to understand the human history on the plateau and human adaptation to high elevation environment. Hence, 151 site, a paleo- to Epi-Paleolithic site in the Qinghai Lake basin on NETP, is chosen to excavate. Thousands pieces of animal bones, hundreds pieces of stone artifacts and several possible hearths were unearthed and obtained during two excavation seasons. Carefully redating of the site shows that it was first occupied shortly around 15 ka BP, then reoccupied from 9000-6000 a BP more intensely. Preliminary study of the site suggest that the first appearance of human in Qinghai Lake basin is closely related to the amelioration of the Last Deglaciation and the prevalence of microlithic technology in North China, which may enlighten the study of early human migration on to whole plateau; however, the latter more intense human occupation in 151 site is not only closely related to the warm and stable early-mid Holocene climate but also provoked by early millet agriculture in neighbor low-elevation Loess plateau.

  2. A Dynamical Analysis of the Suitability of Prehistoric Spheroids from the Cave of Hearths as Thrown Projectiles

    PubMed Central

    Wilson, Andrew D.; Zhu, Qin; Barham, Lawrence; Stanistreet, Ian; Bingham, Geoffrey P.

    2016-01-01

    Spheroids are ball-shaped stone objects found in African archaeological sites dating from 1.8 million years ago (Early Stone Age) to at least 70,000 years ago (Middle Stone Age). Spheroids are either fabricated or naturally shaped stones selected and transported to places of use making them one of the longest-used technologies on record. Most hypotheses about their use suggest they were percussive tools for shaping or grinding other materials. However, their size and spherical shape make them potentially useful as projectile weapons, a property that, uniquely, humans have been specialised to exploit for millions of years. Here we show (using simulations of projectile motions resulting from human throwing) that 81% of a sample of spheroids from the late Acheulean (Bed 3) at the Cave of Hearths, South Africa afford being thrown so as to inflict worthwhile damage to a medium-sized animal over distances up to 25 m. Most of the objects have weights that produce optimal levels of damage from throwing, rather than simply being as heavy as possible (as would suit other functions). Our results show that these objects were eminently suitable for throwing, and demonstrate how empirical research on behavioural tasks can inform and constrain our theories about prehistoric artefacts. PMID:27506611

  3. Analysis of a prehistoric Egyptian iron bead with implications for the use and perception of meteorite iron in ancient Egypt

    NASA Astrophysics Data System (ADS)

    Johnson, Diane; Tyldesley, Joyce; Lowe, Tristan; Withers, Philip J.; Grady, Monica M.

    2013-06-01

    Tube-shaped beads excavated from grave pits at the prehistoric Gerzeh cemetery, approximately 3300 BCE, represent the earliest known use of iron in Egypt. Using a combination of scanning electron microscopy and micro X-ray microcomputer tomography, we show that microstructural and chemical analysis of a Gerzeh iron bead is consistent with a cold-worked iron meteorite. Thin fragments of parallel bands of taenite within a meteoritic Widmanstätten pattern are present, with structural distortion caused by cold-working. The metal fragments retain their original chemistry of approximately 30 wt% nickel. The bulk of the bead is highly oxidized, with only approximately 2.4% of the total bead volume remaining as metal. Our results show that the first known example of the use of iron in Egypt was produced from a meteorite, its celestial origin having implications for both the perception of meteorite iron by ancient Egyptians and the development of metallurgical knowledge in the Nile Valley.

  4. Evidence of prehistoric flooding and the potential for future extreme flooding at Coyote Wash, Yucca Mountain, Nye County, Nevada

    USGS Publications Warehouse

    Glancy, Patrick A.

    1994-01-01

    Coyote Wash, east of Yucca Mountain and southwest of the Nevada Test Site, is the potential location for an exploratory shaft to investigate the feasibility of underground storage of radioactive waste. The potential for flooding and related fluvial-debris hazards was investigated with respect to the potential shaft location. Trenches excavated through fluvial sediment deposits revealed interstratified rock detritus emplaced by floods and debris flows. Most of the deposits are believed to be of late Quaternary age. Debros-flow deposits contain boulders as large as 3 feet in diameter. This evidence of intense prehistoric flooding and debris movement indicates the possibility of similar continuing activity. Empirical estimates of extreme flood flows in North Fork Coyote Wash, a 0.094- square-mile drainage to the shaft site, range from 900 to 2,600 cubic feet per second. Current (1992) knowledge indicates that flows of water and debris as much as 2,500 cubic feet per second can occur in the vicinity of the shaft from this drainage. Similar size flows from adjacent South Fork Coyote Wash, could arrive simultaneously in the vicinity of the shaft. Thus, cumulative water and debris from both tributaries could subject the alluvial flood plain near the shaft site to flows of as much as 5,000 cubic feet per second.

  5. Ochres from rituals of prehistoric human funerals at the Toca do Enoque site, Piauí, Brazil

    NASA Astrophysics Data System (ADS)

    Cavalcante, Luis Carlos Duarte; da Luz, Maria De Fátima; Guidon, Niéde; Fabris, José Domingos; Ardisson, José Domingos

    2011-11-01

    The archaeological site known as Toca do Enoque (geographical coordinates, 09° 14' 65.3″ S 43° 55' 62.5″ W) is a rock shelter located in the Serra das Andorinhas (Serra das Confusões National Park), rural area of the city of Guaribas, state of Piauí, Brazil. Several rupestrian paintings (anthropomorphic and zoomorphic motifs along with some pure graphisms), predominantly in red, are found on the sandstone walls. Charcoals, lithic materials, necklaces with teeth, animal bones, gastropod shells, ochres and human skeletons (dated from 6,220 ± 40 to 6,610 ± 40 years before present, BP) were identified in recent excavations in this shelter. Red and yellow ochre samples were collected from prehistoric funeral structures and analyzed with powder X-ray diffractometry, Fourier-transform infrared spectroscopy and 57Fe transmission Mössbauer spectroscopy at 298 K and 80 K. Mössbauer data indicate that the red ochre do contain predominantly hematite ( α-Fe2O3) whereas goethite ( α-FeOOH) is the major mineral in the yellow ochre.

  6. A Dynamical Analysis of the Suitability of Prehistoric Spheroids from the Cave of Hearths as Thrown Projectiles.

    PubMed

    Wilson, Andrew D; Zhu, Qin; Barham, Lawrence; Stanistreet, Ian; Bingham, Geoffrey P

    2016-08-10

    Spheroids are ball-shaped stone objects found in African archaeological sites dating from 1.8 million years ago (Early Stone Age) to at least 70,000 years ago (Middle Stone Age). Spheroids are either fabricated or naturally shaped stones selected and transported to places of use making them one of the longest-used technologies on record. Most hypotheses about their use suggest they were percussive tools for shaping or grinding other materials. However, their size and spherical shape make them potentially useful as projectile weapons, a property that, uniquely, humans have been specialised to exploit for millions of years. Here we show (using simulations of projectile motions resulting from human throwing) that 81% of a sample of spheroids from the late Acheulean (Bed 3) at the Cave of Hearths, South Africa afford being thrown so as to inflict worthwhile damage to a medium-sized animal over distances up to 25 m. Most of the objects have weights that produce optimal levels of damage from throwing, rather than simply being as heavy as possible (as would suit other functions). Our results show that these objects were eminently suitable for throwing, and demonstrate how empirical research on behavioural tasks can inform and constrain our theories about prehistoric artefacts.

  7. History and Mechanism of Prehistoric Human Dispersal to the Tibetan Plateau and Adaptation to the High Altitude Environment

    NASA Astrophysics Data System (ADS)

    Chen, F.; Zhang, D.; Dong, G.

    2016-12-01

    Human history of the Tibetan Plateau and human adaptation to the high-altitude environment is hotly debated in the past decade among archaeological, anthropological, genetic, and even past climate change studies. Based on previous studies on the Tibetan Plateau and our own archaeological studies in northeastern Tibetan Plateau (NETP), we propose that there was a long history for prehistorical humans to migrate and adapt to the Tibetan Plateau from the last Deglacial period to late Holocene mainly from lowland North China via Yellow River valley and its tributary valleys in NETP. This migration is constituted of four stages (Upper Paleolithic, Epipaleolithic, Neolithic and Bronze Age) during which human adapted to the high altitude environment and climate changes with different strategies and techniques. Particularly, the prevail of microlithic technology in North China provoked relative large hunter-gatherer group's first visit to the NETP in relatively ameliorated last Deglacial period, and the quick development of millet farming in lowland yellow river valley, and subsequent mixed barley-wheat farming and sheep herding facilitated farmers and herders permanently settled down on NETP, even above 3000 masl, during mid- and late Holocene at about 3600 years ago. However, human activity on the Tibetan Plateau during the Epipaleolithic period, and even earlier than 15 ka BP is still uncertain and needs more careful study. A new special NSFC project will be implemented to solve these problems from 2017 to 2021 and welcome interesting scientists to collaborate with us.

  8. Agricultural Occupations Program Planning Guide.

    ERIC Educational Resources Information Center

    Hemp, Paul E.; Mayer, Leon

    The major program objectives of agricultural occupations courses are (1) to develop agricultural competencies needed by individuals engaged in or preparing to engage in production agriculture, and in agricultural occupations other than production agriculture; (2) to develop an understanding of the career opportunities in agriculture; (3) to…

  9. Agricultural Occupations Programs Planning Guides

    ERIC Educational Resources Information Center

    Stitt, Thomas R.; And Others

    1977-01-01

    A set of program planning guides that include seven areas (1) Agricultural Production, (2) Agricultural Supplies and Services, (3) Agricultural Mechanics, (4) Agricultural Products, (5) Ornamental Horticulture, (6) Agricultural Resources, and (7) Forestry, were developed and introduced to high school applied biological and agricultural occupations…

  10. [Mycobacterium infection in prehistoric humans: co-evolution in remote ages].

    PubMed

    Sabbatani, Sandro; Fiorini, Sirio

    2015-03-01

    The introduction of agriculture and animal husbandry at the end of the Mesolithic era, despite enabling a significant demographic growth through an increase in food storage and availability, caused new infectious noxae to enter the pathocoenosis. However in the Palaeolithic era, hunter-gatherers were already in contact with infectious diseases of animal origin, albeit episodically. Modern biomedical technologies allow us to estimate, with better approximation, how long mankind has been in contact with Mycobacterium tuberculosis. Archaeological finds, including human and animal remains (especially the aurochs), are particularly studied by palaeopathologists, as mycobacteria frequently cause bone involvement and this characteristic is of particular interest for palaeopathological (even macroscopic) studies; the interest is to detect the ancient DNA of MT, which is the cause of bone tuberculosis in skeletal remains as well as in mummies. According to our present knowledge, palaeopathological findings, confirmed by molecular techniques, suggest that tuberculosis in human skeletons goes back at most to 9000 years ago, while, in a veterinary environment, the most ancient DNA of MTBC to be detected in an American bison dates back about 17,000 years. The possibility of discovering archaeological finds making even more ancient human remains available leaves opens up the possibility of dating back to previous eras the transmission of MTBC infection to mankind. Phylogenetic works examining the available materials (DNAa) suggest that Mycobacterium tuberculosis, the cause of tuberculosis infection in humans and cattle (Aurochs), would have had a co-evolutionary process. On the basis of recent phylogenetic studies, the MTBC genome would have had a wide span of time to reach a suitable adjustment, co-evolving in geographical environments both at high and low host density. It is likely that the strains that did not show this strong "flexibility" underwent extinction, in favour of

  11. Estimation of actual irrigation amount and its impact on groundwater depletion: A case study in the Hebei Plain, China

    NASA Astrophysics Data System (ADS)

    Hu, Xiaolong; Shi, Liangsheng; Zeng, Jicai; Yang, Jinzhong; Zha, Yuanyuan; Yao, Yunjun; Cao, Guoliang

    2016-12-01

    Irrigation water is an important but missing hydrological cycle component in the region with intensive agricultural irrigation, due to the lack of monitoring facilities. The Hebei Plain, suffering the most severe groundwater depletion in China for agriculture production, provides an ideal background to study historical agricultural water consumption and its dependence on groundwater exploitation. This paper investigated the method of retrieving the spatial-temporal irrigation amount from multiple data sets of different sources and different scales. Comprehensive data including 21 years of satellite-based data, ground-based data, and four years of tracer experiment data are synthesized to implement the soil water balance. We proposed a modified soil water balance framework by relying on as much as possible of easily available data. Our results showed that the multi-mean annual irrigation amount in the Hebei Plain is 317 mm, and mean irrigation-to-evapotranspiration ratio reaches 50.8% in recent two decades. Moreover, the precipitation distribution, plant structure, and agricultural intensity result in significantly spatiotemporal variation in irrigation and irrigation-to-evapotranspiration ratio, while however has not been addressed by previous studies. Deep percolation, ignored by many soil water balance models, was shown to be unneglectable. The estimated actual irrigation amount, together with groundwater level data, are valuable to obtain a further understanding on groundwater depletion. The diverse groundwater depletion situation in the Hebei Plain indicated the importance of recognizing the groundwater utilization patterns at a smaller scale in the regional-scale groundwater resources management. This work showed the feasibility of estimating the irrigation amount using simultaneously different types of data and revealed the spatiotemporal characteristics of agriculture water consumption and associated groundwater depletion in the Hebei Plain.

  12. Agricultural aviation research

    NASA Technical Reports Server (NTRS)

    Chevalier, H. L. (Compiler); Bouse, L. F. (Compiler)

    1977-01-01

    A compilation of papers, comments, and results is provided during a workshop session. The purpose of the workshop was to review and evaluate the current state of the art of agricultural aviation, to identify and rank potentially productive short and long range research and development areas, and to strengthen communications between research scientists and engineers involved in agricultural research. Approximately 71 individuals actively engaged in agricultural aviation research were invited to participate in the workshop. These were persons familiar with problems related to agricultural aviation and processing expertise which are of value for identifying and proposing beneficial research.

  13. Hydrogeological aspects of agricultural drainage in Ireland

    NASA Astrophysics Data System (ADS)

    Burdon, David J.

    1986-02-01

    Hydrogeological principles and approaches have been applied to the problems of agricultural drainage in Ireland in the hope that such application will contribute to the better solution of the many drainage problems in Ireland. The legal position and a short history of drainage in Ireland are given, as well as a list of the many state bodies involved in arterial and agricultural drainage. The evolution of the present Irish environment is outlined, from the end of the last ice age to the present day, with emphasis on the formation of lands in need of drainage. Natural conditions indicate that agricultural drainage was required over some 50% (34,450 km2) of Ireland; the achieved agricultural drainage extends over some 29.3% of the country. Natural conditions affecting drainage are set out under the headings of topographical, geological, hydrogeological, vegetative, and hydrochemical influences as well as man's actions with regard to drainage. The third portion of the article deals with the ways in which areas now requiring agricultural drainage have been formed. Areas of low or nil infiltration are described, with some emphasis on such occurrences as lacustrine marls, pans of various types, the effects of the Calp and the Namurian in Carboniferous strate, and conditions under which rejected recharge by overfull aquifers produces winter marshes. Then areas afflicted by high, but often diffuse, groundwater discharge are noted. And the effect of bog growth, both raised bogs and blanket bog, are outlined; drainage of bogs is a very specialized operation, mainly undertaken by Bord na Mona. Some of the harmful affects of drainage are outlined, as reduction of grazing during rare droughts, of lands suitable for waterfowl, as well as some pollution from bog drainage. Drainage does not deplete the groundwater resources of Ireland, which are abundant and little used. The article ends with some general conclusions and a list of some 13 unusual ideas which arise from the

  14. The impact of first-generation biofuels on the depletion of the global phosphorus reserve.

    PubMed

    Hein, Lars; Leemans, Rik

    2012-06-01

    The large majority of biofuels to date is "first-generation" biofuel made from agricultural commodities. All first-generation biofuel production systems require phosphorus (P) fertilization. P is an essential plant nutrient, yet global reserves are finite. We argue that committing scarce P to biofuel production involves a trade-off between climate change mitigation and future food production. We examine biofuel production from seven types of feedstock, and find that biofuels at present consume around 2% of the global inorganic P fertilizer production. For all examined biofuels, with the possible exception of sugarcane, the contribution to P depletion exceeds the contribution to mitigating climate change. The relative benefits of biofuels can be increased through enhanced recycling of P, but high increases in P efficiency are required to balance climate change mitigation and P depletion impacts. We conclude that, with the current production systems, the production of first-generation biofuels compromises food production in the future.

  15. 26 CFR 1.642(e)-1 - Depreciation and depletion.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Depreciation and depletion. 1.642(e)-1 Section 1... (CONTINUED) INCOME TAXES Estates, Trusts, and Beneficiaries § 1.642(e)-1 Depreciation and depletion. An estate or trust is allowed the deductions for depreciation and depletion, but only to the extent...

  16. 26 CFR 52.4682-1 - Ozone-depleting chemicals.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 17 2013-04-01 2013-04-01 false Ozone-depleting chemicals. 52.4682-1 Section 52... EXCISE TAXES (CONTINUED) ENVIRONMENTAL TAXES § 52.4682-1 Ozone-depleting chemicals. (a) Overview. This section provides rules relating to the tax imposed on ozone-depleting chemicals (ODCs) under section...

  17. 26 CFR 52.4682-1 - Ozone-depleting chemicals.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 17 2011-04-01 2011-04-01 false Ozone-depleting chemicals. 52.4682-1 Section 52... EXCISE TAXES (CONTINUED) ENVIRONMENTAL TAXES § 52.4682-1 Ozone-depleting chemicals. (a) Overview. This section provides rules relating to the tax imposed on ozone-depleting chemicals (ODCs) under section...

  18. 26 CFR 52.4682-1 - Ozone-depleting chemicals.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 17 2014-04-01 2014-04-01 false Ozone-depleting chemicals. 52.4682-1 Section 52... EXCISE TAXES (CONTINUED) ENVIRONMENTAL TAXES § 52.4682-1 Ozone-depleting chemicals. (a) Overview. This section provides rules relating to the tax imposed on ozone-depleting chemicals (ODCs) under section...

  19. 26 CFR 52.4682-1 - Ozone-depleting chemicals.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 17 2012-04-01 2012-04-01 false Ozone-depleting chemicals. 52.4682-1 Section 52... EXCISE TAXES (CONTINUED) ENVIRONMENTAL TAXES § 52.4682-1 Ozone-depleting chemicals. (a) Overview. This section provides rules relating to the tax imposed on ozone-depleting chemicals (ODCs) under section...

  20. Children's Models of the Ozone Layer and Ozone Depletion.

    ERIC Educational Resources Information Center

    Christidou, Vasilia; Koulaidis, Vasilis

    1996-01-01

    The views of 40 primary students on ozone and its depletion were recorded through individual, semi-structured interviews. The data analysis resulted in the formation of a limited number of models concerning the distribution and role of ozone in the atmosphere, the depletion process, and the consequences of ozone depletion. Identifies five target…

  1. Children's Models of the Ozone Layer and Ozone Depletion.

    ERIC Educational Resources Information Center

    Christidou, Vasilia; Koulaidis, Vasilis

    1996-01-01

    The views of 40 primary students on ozone and its depletion were recorded through individual, semi-structured interviews. The data analysis resulted in the formation of a limited number of models concerning the distribution and role of ozone in the atmosphere, the depletion process, and the consequences of ozone depletion. Identifies five target…

  2. Potential For Stratospheric Ozone Depletion During Carboniferous

    NASA Astrophysics Data System (ADS)

    Bill, M.; Goldstein, A. H.

    Methyl bromide (CH3Br) constitutes the largest source of bromine atoms to the strato- sphere whereas methyl chloride (CH3Cl) is the most abundant halocarbon in the tro- posphere. Both gases play an important role in stratospheric ozone depletion. For in- stance, Br coupled reactions are responsible for 30 to 50 % of total ozone loss in the polar vortex. Currently, the largest natural sources of CH3Br and CH3Cl appear to be biological production in the oceans, inorganic production during biomass burning and plant production in salt marsh ecosystems. Variations of paleofluxes of CH3Br and CH3Cl can be estimated by analyses of oceanic paleoproductivity, stratigraphic analyses of frequency and distribution of fossil charcoal indicating the occurrence of wildfires, and/or by paleoreconstruction indicating the extent of salt marshes. Dur- ing the lower Carboniferous time (Tournaisian-Visean), the southern margin of the Laurasian continent was characterized by charcoal deposits. Estimation on frequency of charcoal layers indicates that wildfires occur in a range of 3-35 years (Falcon-Lang 2000). This suggests that biomass burning could be an important source of CH3Br and CH3Cl during Tournaisian-Viesan time. During Tounaisian and until Merame- cian carbon and oxygen isotope records have short term oscillations (Bruckschen et al. 1999, Mii et al. 1999). Chesterian time (mid- Carboniferous) is marked by an in- crease in delta18O values ( ~ 2 permil) and an increase of glacial deposit frequency suggesting lower temperatures. The occurrence of glacial deposits over the paleopole suggests polar conditions and the associated special features of polar mete- orology such as strong circumpolar wind in the stratosphere (polar vortex) and polar stratospheric clouds. Thus, conditions leading to polar statospheric ozone depletion can be found. Simultaneously an increase in delta13C values is documented. We interpret the positive shift in delta13C as a result of higher bioproductivity

  3. Evolution of the Depleted Mantle--Revisited

    NASA Astrophysics Data System (ADS)

    Vervoort, J. D.

    2011-12-01

    One of the basic tenets of radiogenic isotope geochemistry is that the Earth's crust has been extracted from the mantle leaving the mantle depleted in incompatible elements. Two tracers that have been used to constrain depleted mantle (DM) evolution are the long-lived radiogenic isotope systems Sm-Nd and Lu-Hf. It has long been assumed that Nd evolution of the depleted mantle follows a ~ linear path from chondritic composition (ɛNd = 0) at ~4.5 Ga to depleted MORB mantle (DMM) today (ɛNd = +10) [e.g., 1]. The Hf isotope system, before the revision of the 176Lu decay constant [2,3], appeared follow a similar evolution: chondritic at ~4.5 Ga to DMM today [4]. This relationship, however, changed radically with the revision of the 176Lu decay constant. Now, for the Lu-Hf isotope system, there is no evidence of a widespread depleted mantle prior to 3.5 Ga. Using the new decay constant and CHUR values [5], Hf data for juvenile, mantle-derived rocks through time define a trend that does not diverge from chondritic compositions until after 3.5 Ga. This new Hf DM evolution is defined by average DMM today (176Hf/177Hf = 0.28321, ɛHf =~ +15) and using 176Lu/177Hf = 0.0399 to calculate compositions back in time to CHUR at 3.5 Ga. The Hf-Nd isotope records, therefore, appear to indicate different evolutionary histories: Nd isotopes show evidence for widespread depleted mantle from the earliest preserved rocks [6] and; Hf isotopes show only chondritic to enriched sources for the oldest preserved rocks [7]. This "Hf-Nd paradox", if the reference frames are correct, would imply that differentiation of the early Earth affected the Sm-Nd and Lu-Hf systems in fundamentally differently ways-a premise that seems difficult to explain. A further complication in the Hf and Nd evolution of the Earth comes from the short-lived isotope system 146Sm-142Nd. An unavoidable consequence of the 142Nd data is that the silicate Earth sampled thus far has a super chondritic Sm/Nd composition [e

  4. Modules in Agricultural Education for Agricultural Resources.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Occupational and Career Curriculum Development.

    Each of the 31 curriculum modules in this packet for agricultural resources instruction contains a brief description of the module content, a list of the major division or units, the overall objective, objectives by units, content outline and suggested teaching methods, student application activities, and evaluation procedures. A list of resource…

  5. Modules in Agricultural Education for Agricultural Mechanics.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Bureau of Occupational and Career Curriculum Development.

    Each of the 38 curriculum modules in this packet for agricultural mechanics instruction contains a brief description of the module content, a list of the major divisions or units, the overall objectives, objectives by unit, content outline and suggested teaching methods, student application activities, and evaluation procedures. A listing of…

  6. VOCATIONAL AGRICULTURE RECORD BOOK FOR PRODUCTION AGRICULTURE.

    ERIC Educational Resources Information Center

    1966

    FORMS ARE PROVIDED FOR RECORDING FINANCIAL INFORMATION ABOUT SUPERVISED FARM PROGRAM ENTERPRISES BY INDIVIDUAL VOCATIONAL AGRICULTURE STUDENTS. THE BOOK IS DESIGNED ON AN ENTERPRISE BASIS AND PROVIDES SPACE FOR AGREEMENTS, INVENTORIES, EXPENSES, INCOME, SUMMARIES, AND ANALYSES. ASSISTANCE FOR TEACHERS USING THIS RECORD BOOK IS AVAILABLE IN "GUIDE…

  7. A modern depleted uranium manufacturing facility

    SciTech Connect

    Zagula, T.A.

    1995-07-01

    The Specific Manufacturing Capabilities (SMC) Project located at the Idaho National Engineering Laboratory (INEL) and operated by Lockheed Martin Idaho Technologies Co. (LMIT) for the Department of Energy (DOE) manufactures depleted uranium for use in the U.S. Army MIA2 Abrams Heavy Tank Armor Program. Since 1986, SMC has fabricated more than 12 million pounds of depleted uranium (DU) products in a multitude of shapes and sizes with varying metallurgical properties while maintaining security, environmental, health and safety requirements. During initial facility design in the early 1980`s, emphasis on employee safety, radiation control and environmental consciousness was gaining momentum throughout the DOE complex. This fact coupled with security and production requirements forced design efforts to focus on incorporating automation, local containment and computerized material accountability at all work stations. The result was a fully automated production facility engineered to manufacture DU armor packages with virtually no human contact while maintaining security, traceability and quality requirements. This hands off approach to handling depleted uranium resulted in minimal radiation exposures and employee injuries. Construction of the manufacturing facility was complete in early 1986 with the first armor package certified in October 1986. Rolling facility construction was completed in 1987 with the first certified plate produced in the fall of 1988. Since 1988 the rolling and manufacturing facilities have delivered more than 2600 armor packages on schedule with 100% final product quality acceptance. During this period there was an annual average of only 2.2 lost time incidents and a single individual maximum radiation exposure of 150 mrem. SMC is an example of designing and operating a facility that meets regulatory requirements with respect to national security, radiation control and personnel safety while achieving production schedules and product quality.

  8. Pumping induced depletion from two streams

    NASA Astrophysics Data System (ADS)

    Sun, Dongmin; Zhan, Hongbin

    2007-04-01

    We have proved that the Hantush's model [Hantush MS. Wells near streams with semipervious beds. J Geophys Res 1965;70:2829-38] in a half-domain can be extended to a whole-domain and becomes identical to that of Hunt [Hunt B. Unsteady stream depletion from ground water pumping. Ground Water 1999;37(1):98-102] for a shallow and infinitely narrow stream, provided that the Dupuit assumption is adopted. This proof helps correct a false concept that regards the Hantush's model as less useful because of its fully penetrating stream assumption. This study deals with interaction of an aquifer with two parallel streams based on the Hantush's model. Semi-analytical solutions are obtained based on rigorous mass conservation requirement by maintaining continuity of flux and head along the aquifer-streambed boundaries. This study shows that the hydraulic conductivity ratio of the two streambeds appears to be the most important factor controlling the stream-aquifer interaction, followed by a less important role played by the thickness ratio of the two streambeds. When the low-permeability streambeds do not exist, the steady-state stream depletion from one stream is linearly proportional to the ratio of the shortest distance from the pumping well to the other stream over the shortest distance between the two streams. When the low-permeability streambeds are presented, similar conclusion can be drawn except that the stream depletion now also strongly depends on the hydraulic conductivity ratio of the two streambeds. When the values of the hydraulic conductivity of the two streambeds are different by an order of magnitude, the location of the pumping well that receives equal flux from two streams can be off the middle-line between the two streams by nearly 90%.

  9. Zn2+ depletion blocks endosome fusion.

    PubMed Central

    Aballay, A; Sarrouf, M N; Colombo, M I; Stahl, P D; Mayorga, L S

    1995-01-01

    Fusion among endosomes is an important step for transport and sorting of internalized macromolecules. Working in a cell-free system, we previously reported that endosome fusion requires cytosol and ATP, and is sensitive to N-ethylmaleimide. Fusion is regulated by monomeric and heterotrimeric GTP-binding proteins. We now report that fusion can proceed at very low Ca2+ concentrations, i.e. < 30 nM. Moreover, fusion is not affected when intravesicular Ca2+ is depleted by preincubation of vesicles with calcium ionophores (5 microM ionomycin or A23187) in the presence of calcium chelators (5 mM EGTA or 60 mM EDTA). The results indicate that fusion can proceed at extremely low concentrations of intravesicular and extravesicular Ca2+. However, BAPTA [1,2-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid], a relatively specific Ca2+ chelator, inhibits fusion. BAPTA binds other metals besides Ca2+. We present evidence that BAPTA inhibition is due not to Ca2+ chelation but to Zn2+ depletion. TPEN [N,N,N',N'-tetrakis-(2-pyridylmethyl) ethylenediamine], another metal-ion chelator with low affinity for Ca2+, also inhibited fusion. TPEN- and BAPTA-inhibited fusions were restored by addition of Zn2+. Zn(2+)-dependent fusion presents the same characteristics as control fusion. In intact cells, TPEN inhibited transport along the endocytic pathway. The results indicate that Zn2+ depletion blocks endosome fusion, suggesting that this ion is necessary for the function of one or more factors involved in the fusion process. Images Figure 1 PMID:8554539

  10. Rhenium Disulfide Depletion-Load Inverter

    NASA Astrophysics Data System (ADS)

    McClellan, Connor; Corbet, Chris; Rai, Amritesh; Movva, Hema C. P.; Tutuc, Emanuel; Banerjee, Sanjay K.

    2015-03-01

    Many semiconducting Transition Metal Dichalcogenide (TMD) materials have been effectively used to create Field-Effect Transistor (FET) devices but have yet to be used in logic designs. We constructed a depletion-load voltage inverter using ultrathin layers of Rhenium Disulfide (ReS2) as the semiconducting channel. This ReS2 inverter was fabricated on a single micromechanically-exfoliated flake of ReS2. Electron beam lithography and physical vapor deposition were used to construct Cr/Au electrical contacts, an Alumina top-gate dielectric, and metal top-gate electrodes. By using both low (Aluminum) and high (Palladium) work-function metals as two separate top-gates on a single ReS2 flake, we create a dual-gated depletion mode (D-mode) and enhancement mode (E-mode) FETs in series. Both FETs displayed current saturation in the output characteristics as a result of the FET ``pinch-off'' mechanism and On/Off current ratios of 105. Field-effect mobilities of 23 and 17 cm2V-1s-1 and subthreshold swings of 97 and 551 mV/decade were calculated for the E-mode and D-mode FETs, respectively. With a supply voltage of 1V, at low/negative input voltages the inverter output was at a high logic state of 900 mV. Conversely with high/positive input voltages, the inverter output was at a low logic state of 500 mV. The inversion of the input signal demonstrates the potential for using ReS2 in future integrated circuit designs and the versatility of depletion-load logic devices for TMD research. NRI SWAN Center and ARL STTR Program.

  11. Scientific assessment of ozone depletion: 1991

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Over the past few years, there have been highly significant advances in the understanding of the impact of human activities on the Earth's stratospheric ozone layer and the influence of changes in chemical composition of the radiative balance of the climate system. Specifically, since the last international scientific review (1989), there have been five major advances: (1) global ozone decreases; (2) polar ozone; (3) ozone and industrial halocarbons; (4) ozone and climate relations; and (5) ozone depletion potentials (ODP's) and global warming potentials (GWP's). These topics and others are discussed.

  12. Ozone Depletion and Biologically Relevant Ultraviolet Radiation.

    NASA Astrophysics Data System (ADS)

    Zeng, Jun

    1995-01-01

    An atmospheric radiative transfer model is used to calculate surface spectral ultraviolet irradiance under cloud-free conditions, and compared with measurements made at Lauder, New Zealand (45^circ{S }, 170^circ{E}) before and after the eruption of Mt. Pinatubo, and including a snow-covered surface. The ratios of diffuse to direct irradiance depend critically on solar elevation, surface albedo, and aerosol extinction. Ozone changes have pronounced effects on the global UVB irradiance, but have only a minor effect on these ratios. The comparison suggests that the ultraviolet radiation exposure can be computed with confidence for clear sky conditions, if the appropriate atmospheric pressure and temperature profiles, ozonesonde data, surface albedo, and aerosol optical properties are available. The total ozone abundances are derived by using ground-based UV irradiance measurements and compared with TOMS in Antarctica and the Arctic from 1990 to 1994. The comparisons show that they are generally in good agreement. Possible reasons for the discrepancies between the two methods are discussed. The equivalent cloud optical depths are also inferred from these data. Ozone depletion can also increase the penetration of ultraviolet radiation into the aquatic system. A coupled atmosphere-ocean radiative transfer model is used to investigate the effect of ozone depletion on UV penetration through the atmosphere and into the underlying water column. Comparisons between model computations and in situ measurements of irradiances made in Antarctic water show good agreement in the UV spectral range between 300 and 350 nm. The ratio of UVB (280-320 nm) to total (280-700 nm) irradiance also compared well. For a given ozone reduction the largest relative increase of UVB radiation arriving at the surface and penetrating to various depths in the ocean occurs at large solar zenith angles. At high latitudes the most pronounced increase in UVB exposure due to an ozone depletion occurs in the

  13. Depletion of the Outer Asteroid Belt

    NASA Technical Reports Server (NTRS)

    Liou, Jer-Chyi; Malhotra, Renu

    1997-01-01

    During the early history of the solar system, it is likely that the outer planets changed their distance from the sun, and hence, their influence on the asteroid belt evolved with time. The gravitational influence of Jupiter and Saturn on the orbital evolution of asteroids in the outer asteroid belt was calculated. The results show that the sweeping of mean motion resonances associated with planetary migration efficiently destabilizes orbits in the outer asteroid belt on a time scale of 10 million years. This mechanism provides an explanation for the observed depletion of asteroids in that region.

  14. Ozone depletion: implications for the veterinarian.

    PubMed

    Kopecky, K E

    1978-09-15

    Man has inadvertently modified the stratosphere. There is a good possibility that the ozone layer is being depleted by the use of jet aircraft (SST), chlorofluoromethane propellants, and nitrogen fertilizers. Under unpolluted conditions, the production of ozone equals its destruction. By man's intervention, however, the destruction may exceed the production. The potential outcome is increased intensity of solar ultraviolet (280-400 nm) radiation and penetration to the earth's surface of previously absorbed wavelengths below about 280 nm. The increased ultraviolet radiation would increase the likelihood of skin cancer in man and ocular squamous cell carcinoma in cattle. The climate also might be modified, possibly in an undesirable way.

  15. Depletion of the Outer Asteroid Belt

    PubMed

    Liou; Malhotra

    1997-01-17

    During the early history of the solar system, it is likely that the outer planets changed their distance from the sun, and hence, their influence on the asteroid belt evolved with time. The gravitational influence of Jupiter and Saturn on the orbital evolution of asteroids in the outer asteroid belt was calculated. The results show that the sweeping of mean motion resonances associated with planetary migration efficiently destabilizes orbits in the outer asteroid belt on a time scale of 10 million years. This mechanism provides an explanation for the observed depletion of asteroids in that region.

  16. Capstone Depleted Uranium Aerosols: Generation and Characterization

    SciTech Connect

    Parkhurst, MaryAnn; Szrom, Fran; Guilmette, Ray; Holmes, Tom; Cheng, Yung-Sung; Kenoyer, Judson L.; Collins, John W.; Sanderson, T. Ellory; Fliszar, Richard W.; Gold, Kenneth; Beckman, John C.; Long, Julie

    2004-10-19

    In a study designed to provide an improved scientific basis for assessing possible health effects from inhaling depleted uranium (DU) aerosols, a series of DU penetrators was fired at an Abrams tank and a Bradley fighting vehicle. A robust sampling system was designed to collect aerosols in this difficult environment and continuously monitor the sampler flow rates. Aerosols collected were analyzed for uranium concentration and particle size distribution as a function of time. They were also analyzed for uranium oxide phases, particle morphology, and dissolution in vitro. The resulting data provide input useful in human health risk assessments.

  17. Correlation between cosmic rays and ozone depletion.

    PubMed

    Lu, Q-B

    2009-03-20

    This Letter reports reliable satellite data in the period of 1980-2007 covering two full 11-yr cosmic ray (CR) cycles, clearly showing the correlation between CRs and ozone depletion, especially the polar ozone loss (hole) over Antarctica. The results provide strong evidence of the physical mechanism that the CR-driven electron-induced reaction of halogenated molecules plays the dominant role in causing the ozone hole. Moreover, this mechanism predicts one of the severest ozone losses in 2008-2009 and probably another large hole around 2019-2020, according to the 11-yr CR cycle.

  18. Commercialisation of full depletion scientific CCDs

    NASA Astrophysics Data System (ADS)

    Jorden, Paul; Ball, Kevin; Bell, Ray; Burt, David; Guyatt, Neil; Hadfield, Kevin; Jerram, Paul; Pool, Peter; Pike, Andrew; Holland, Andrew; Murray, Neil

    2006-06-01

    Following successful manufacture of small-format trial devices we have now designed and manufactured large-format scientific CCDs in high resistivity silicon ('high-rho'). These devices are intended for 'full depletion' operation as backside illuminated sensors for very high red wavelength sensitivity and X-ray imaging spectroscopy at extended energies. Devices of 2k*512 and 2k*4k format, with both single and dual stage output circuits have been manufactured and tested. Design considerations, test results, and commercial manufacturing considerations will be addressed.

  19. Projecting groundwater declines and agricultural production through 2110 in the High Plains Aquifer of Kansas

    NASA Astrophysics Data System (ADS)

    Steward, D. R.; Bruss, P. J.; Yang, X.; Staggenborg, S. A.; Welch, S. M.; Apley, M. D.

    2013-12-01

    Groundwater pumping supports vibrant agricultural production in the High Plains Aquifer region of Kansas, and yet, persistent aquifer depletion threatens the long-term prospects and the capacity to help feed to world's population. A new model is presented to project changes in groundwater storage and agricultural production into the future using methodology recently developed by the authors (Steward et al. 2013). This vertically integrated model directly relates groundwater pumping to corn production and feed for cattle production. Estimates are provided for the time to aquifer depletion, the rate of recharge, and the time it would take to completely refill a depleted aquifer. Estimates are also projected into the future for corn and cattle production. Scenario analysis shows the impacts of reduced pumping today on future groundwater stores and on agricultural production. This knowledge is important for society to balance groundwater use across the demands of the present with the needs of the future.

  20. Agricultural Technology Opportunities.

    ERIC Educational Resources Information Center

    North Carolina State Board of Education, Raleigh. Agricultural Technology Education Section.

    Agricultural education programs available through North Carolina's newly created system of industrial education center, technical institutes, and community colleges are described. The information is for use by administrators, and teachers of adult agricultural courses and counselors of high school dropouts and graduates. It describes the need for…