Origin and diet of the prehistoric hunter-gatherers on the mediterranean island of Favignana (Ègadi Islands, Sicily.

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Marcello A Mannino

Full Text Available Hunter-gatherers living in Europe during the transition from the late Pleistocene to the Holocene intensified food acquisition by broadening the range of resources exploited to include marine taxa. However, little is known on the nature of this dietary change in the Mediterranean Basin. A key area to investigate this issue is the archipelago of the Ègadi Islands, most of which were connected to Sicily until the early Holocene. The site of Grotta d'Oriente, on the present-day island of Favignana, was occupied by hunter-gatherers when Postglacial environmental changes were taking place (14,000-7,500 cal BP. Here we present the results of AMS radiocarbon dating, palaeogenetic and isotopic analyses undertaken on skeletal remains of the humans buried at Grotta d'Oriente. Analyses of the mitochondrial hypervariable first region of individual Oriente B, which belongs to the HV-1 haplogroup, suggest for the first time on genetic grounds that humans living in Sicily during the early Holocene could have originated from groups that migrated from the Italian Peninsula around the Last Glacial Maximum. Carbon and nitrogen isotope analyses show that the Upper Palaeolithic and Mesolithic hunter-gatherers of Favignana consumed almost exclusively protein from terrestrial game and that there was only a slight increase in marine food consumption from the late Pleistocene to the early Holocene. This dietary change was similar in scale to that at sites on mainland Sicily and in the rest of the Mediterranean, suggesting that the hunter-gatherers of Grotta d'Oriente did not modify their subsistence strategies specifically to adapt to the progressive isolation of Favignana. The limited development of technologies for intensively exploiting marine resources was probably a consequence both of Mediterranean oligotrophy and of the small effective population size of these increasingly isolated human groups, which made innovation less likely and prevented transmission of

Origin and Diet of the Prehistoric Hunter-Gatherers on the Mediterranean Island of Favignana (Ègadi Islands, Sicily)

Science.gov (United States)

Mannino, Marcello A.; Catalano, Giulio; Talamo, Sahra; Mannino, Giovanni; Di Salvo, Rosaria; Schimmenti, Vittoria; Lalueza-Fox, Carles; Messina, Andrea; Petruso, Daria; Caramelli, David; Richards, Michael P.; Sineo, Luca

2012-01-01

Hunter-gatherers living in Europe during the transition from the late Pleistocene to the Holocene intensified food acquisition by broadening the range of resources exploited to include marine taxa. However, little is known on the nature of this dietary change in the Mediterranean Basin. A key area to investigate this issue is the archipelago of the Ègadi Islands, most of which were connected to Sicily until the early Holocene. The site of Grotta d’Oriente, on the present-day island of Favignana, was occupied by hunter-gatherers when Postglacial environmental changes were taking place (14,000-7,500 cal BP). Here we present the results of AMS radiocarbon dating, palaeogenetic and isotopic analyses undertaken on skeletal remains of the humans buried at Grotta d’Oriente. Analyses of the mitochondrial hypervariable first region of individual Oriente B, which belongs to the HV-1 haplogroup, suggest for the first time on genetic grounds that humans living in Sicily during the early Holocene could have originated from groups that migrated from the Italian Peninsula around the Last Glacial Maximum. Carbon and nitrogen isotope analyses show that the Upper Palaeolithic and Mesolithic hunter-gatherers of Favignana consumed almost exclusively protein from terrestrial game and that there was only a slight increase in marine food consumption from the late Pleistocene to the early Holocene. This dietary change was similar in scale to that at sites on mainland Sicily and in the rest of the Mediterranean, suggesting that the hunter-gatherers of Grotta d’Oriente did not modify their subsistence strategies specifically to adapt to the progressive isolation of Favignana. The limited development of technologies for intensively exploiting marine resources was probably a consequence both of Mediterranean oligotrophy and of the small effective population size of these increasingly isolated human groups, which made innovation less likely and prevented transmission of fitness

Estimation of the tourism climate in the Hunter Region, Australia, in the early twenty-first century

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Shiue, Ivy; Matzarakis, Andreas

2011-07-01

Existing tourism-related climate information and evaluation are typically based on mean monthly conditions of air temperature and precipitation and do not include thermal perception and other climate parameters relevant for tourists. Here, we quantify climate based on the climate facets relevant to tourism (thermal, physical, aesthetical), and apply the results to the Climate-Tourism-Information-Scheme (CTIS). This paper presents bioclimatic and tourism climatological conditions in the Hunter Region—one of Australia's most popular tourist destinations. In the Hunter Region, generally, temperatures below 15°C occur from April through October, temperatures less than 25°C are expected throughout the whole year, while humidity sits around 50%. As expected, large differences between air temperature and physiologically equivalent temperature (PET) were clearly identified. The widest differences were seen in summer time rather than in the winter period. In addition, cold stress was observed less than 10% of the time in winter while around 40-60% of heat stress was observed in summer time. This correlates with the highest numbers of international visitors, who usually seek a warmer weather, at the beginning of summer time (November and December) and also to the number of domestic visitors, who tend to seek cooler places for recreation and leisure, in late summer (January-March). It was concluded that thermal bioclimate assessment such as PET and CTIS can be applied in the Hunter region, and that local governments and the tourism industry should take an integrated approach to providing more relevant weather and climate information for both domestic and international tourists in the near future.

Beyond the Cut Hunter: A Historical Epidemiology of HIV Beginnings in Central Africa.

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Rupp, Stephanie; Ambata, Philippe; Narat, Victor; Giles-Vernick, Tamara

2016-12-01

In the absence of direct evidence, an imagined "cut hunter" stands in for the index patient of pandemic HIV/AIDS. During the early years of colonial rule, this explanation goes, a hunter was cut or injured from hunting or butchering a chimpanzee infected with simian immunodeficiency virus, resulting in the first sustained human infection with the virus that would emerge as HIV-1M. We argue here that the "cut hunter" relies on a historical misunderstanding and ecological oversimplification of human-chimpanzee (Pan Troglodytes troglodytes) interactions that facilitated pathogenic transmission. This initial host shift cannot explain the beginnings of the HIV/AIDS pandemic. Instead, we must understand the processes by which the virus became transmissible, possibly between Sangha basin inhabitants and ultimately reached Kinshasa. A historical epidemiology of the late nineteenth and twentieth centuries, provides a much-needed corrective to the major shortcomings of the cut hunter. Based on 62 oral historical interviews conducted in southeastern Cameroon and archival research, we show that HIV emerged from ecological, economic, and socio-political transformations of the late nineteenth and twentieth centuries. The gradual imposition of colonial rule built on and reoriented ecologies and economies, and altered older patterns of mobility and sociality. Certain changes may have contributed to the initial viral host shift, but more importantly, facilitated the adaptation of HIV-1M to human-to-human transmission. Our evidence suggests that the most critical changes occurred after 1920. This argument has important implications for public health policy, underscoring recent work emphasizing alternative pathways for zoonotic spillovers into human beings.

Vulnerable Hunter

OpenAIRE

Md.Asha Begum; Y.VishnuPriya; V.ManoranjanBabu; ,O.Srinivasu

2016-01-01

This project "VULNERABLE HUNTER" application main aim is to detect risk in our mobile applications. This application contains modules like Fetch Application, Generate Score, Uninstall and Display Graph. Through this application it detects risk so that this application is very useful to smart phone users Now-a-days so many people are using smart phones and people are crazy about new apps. But by installing all the applications into our mobile may reduce its performance. Some apps c...

Hunter-gatherer energetics and human obesity.

Science.gov (United States)

Pontzer, Herman; Raichlen, David A; Wood, Brian M; Mabulla, Audax Z P; Racette, Susan B; Marlowe, Frank W

2012-01-01

Western lifestyles differ markedly from those of our hunter-gatherer ancestors, and these differences in diet and activity level are often implicated in the global obesity pandemic. However, few physiological data for hunter-gatherer populations are available to test these models of obesity. In this study, we used the doubly-labeled water method to measure total daily energy expenditure (kCal/day) in Hadza hunter-gatherers to test whether foragers expend more energy each day than their Western counterparts. As expected, physical activity level, PAL, was greater among Hadza foragers than among Westerners. Nonetheless, average daily energy expenditure of traditional Hadza foragers was no different than that of Westerners after controlling for body size. The metabolic cost of walking (kcal kg(-1) m(-1)) and resting (kcal kg(-1) s(-1)) were also similar among Hadza and Western groups. The similarity in metabolic rates across a broad range of cultures challenges current models of obesity suggesting that Western lifestyles lead to decreased energy expenditure. We hypothesize that human daily energy expenditure may be an evolved physiological trait largely independent of cultural differences.

The Higgs hunter's guide

CERN Document Server

Gunion, John F; Haber, Howard E; Kane, Gordon L

1989-01-01

The Higgs Hunter's Guide is a definitive and comprehensive guide to the physics of Higgs bosons. In particular, it discusses the extended Higgs sectors required by those recent theoretical approaches that go beyond the Standard Model, including supersymmetry and superstring-inspired models.

Wealth Transmission and Inequality Among Hunter-Gatherers

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Hill, Kim; Marlowe, Frank; Nolin, David; Wiessner, Polly; Gurven, Michael; Bowles, Samuel; Mulder, Monique Borgerhoff; Hertz, Tom; Bell, Adrian

2010-01-01

We report quantitative estimates of intergenerational transmission and population-wide inequality for wealth measures in a set of hunter-gatherer populations. Wealth is defined broadly as factors that contribute to individual or household well-being, ranging from embodied forms such as weight and hunting success to material forms such household goods, as well as relational wealth in exchange partners. Intergenerational wealth transmission is low to moderate in these populations, but is still expected to have measurable influence on an individual’s life chances. Wealth inequality (measured with Gini coefficients) is moderate for most wealth types, matching what qualitative ethnographic research has generally indicated (if not the stereotype of hunter-gatherers as extreme egalitarians). We discuss some plausible mechanisms for these patterns, and suggest ways in which future research could resolve questions about the role of wealth in hunter-gatherer social and economic life. PMID:21151711

Motivations of female Black Hills deer hunters

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Gigliotti, Larry M.; Covelli Metcalf, Elizabeth

2016-01-01

State fish and wildlife agencies are particularly interested in attracting female participation because of the potential to offset declining participation in hunting. Understanding female hunters’ motivations will be critical for designing effective recruitment and retention programs for women hunters. Although female participation in hunting is increasing, males still outnumber females by about tenfold. Gender differences in deer hunters were explored by comparing ratings of eight motivations (social, nature, excitement, meat, challenge, trophy, extra hunting opportunity, and solitude). Hunter types were defined by hunters’ selection of the most important motivation for why they like Black Hills deer hunting. Overall, females and males were relatively similar in their ratings of the eight motivations, and we found 85% gender similarity in the selection of the most important motivation. Women were slightly more motivated by the food aspect of the hunt while men placed slightly more value on the hunt as a sporting activity.

Hunter-gatherer energetics and human obesity.

Directory of Open Access Journals (Sweden)

Herman Pontzer

Full Text Available Western lifestyles differ markedly from those of our hunter-gatherer ancestors, and these differences in diet and activity level are often implicated in the global obesity pandemic. However, few physiological data for hunter-gatherer populations are available to test these models of obesity. In this study, we used the doubly-labeled water method to measure total daily energy expenditure (kCal/day in Hadza hunter-gatherers to test whether foragers expend more energy each day than their Western counterparts. As expected, physical activity level, PAL, was greater among Hadza foragers than among Westerners. Nonetheless, average daily energy expenditure of traditional Hadza foragers was no different than that of Westerners after controlling for body size. The metabolic cost of walking (kcal kg(-1 m(-1 and resting (kcal kg(-1 s(-1 were also similar among Hadza and Western groups. The similarity in metabolic rates across a broad range of cultures challenges current models of obesity suggesting that Western lifestyles lead to decreased energy expenditure. We hypothesize that human daily energy expenditure may be an evolved physiological trait largely independent of cultural differences.

Pottery use by early Holocene hunter-gatherers of the Korean peninsula closely linked with the exploitation of marine resources

Science.gov (United States)

Shoda, Shinya; Lucquin, Alexandre; Ahn, Jae-ho; Hwang, Chul-joo; Craig, Oliver E.

2017-08-01

The earliest pottery on the Korean peninsula dates to the early Holocene, notably later than other regions of East Asia, such as Japan, the Russian Far East and Southern China. To shed light on the function of such early Korean pottery and to understand the motivations for its adoption, organic residue analysis was conducted on pottery sherds and adhered surface deposit on the wall of pottery vessels (foodcrusts) excavated from the Sejuk shell midden (7.7-6.8ka calBP) on the southeastern coast and the Jukbyeon-ri site (7.9-6.9ka calBP) on the eastern coast of the Korean peninsula, that represents the earliest pottery assemblages with reliable radiocarbon dates. Through chemical and isotopic residue analysis, we conclude that the use of pottery at these sites was oriented towards marine resources, supported by lipid biomarkers typical of aquatic organisms and stable carbon isotope values that matched authentic marine reference fats. The findings contrast with other archaeological evidence, which shows that a wider range of available food resources were exploited. Therefore, we conclude pottery was used selectively for processing aquatic organisms perhaps including the rendering of aquatic oils for storage. Early pottery use in Korea is broadly similar to other prehistoric temperate hunter-gatherers, such as in Japan, northern Europe and northern America. However, it is also notable that elaborately decorated red burnished pottery excavated from isolated location at the Jukbyeon-ri site had a different usage pattern, which indicates that division of pottery use by vessel form was established even at this early stage.

Hot subduction: Magmatism along the Hunter Ridge, SW Pacific

International Nuclear Information System (INIS)

Crawford, A.J.; Verbeeten, A.; Danyushevsky, L.V.; Sigurdsson, I.A.; Maillet, P.; Monzier, M.

1997-01-01

The Hunter 'fracture zone' is generally regarded as a transform plate boundary linking the oppositely dipping Tongan and Vanuatu subduction systems. Dredging along the Hunter Ridge and sampling of its northernmost extent, exposed as the island of Kadavu in Fiji, has yielded a diversity of magmatic suites, including arc tholeiites and high-Ca boninites, high-Mg lavas with some affinities to boninites and some affinities to adakites, and true adakitic lavas associated with remarkable low-Fe, high-Na basalts with 8-16 ppm Nb (herein high-Nb basalts). Lavas which show clear evidence of slab melt involvement in their petrogenesis occur at either end of the Hunter Ridge, whereas the arc tholeiites and high-Ca boninites appear to be restricted to the south central part of the ridge. Mineralogical and whole rock geochemical data for each of these suites are summarized, and a tectono-magmatic model for their genesis and distribution is suggested. Trace element features and radiogenic isotope data for the Hunter Ridge lavas indicate compositions analogue to Pacific MORB-like mantle

Legitimization of regulatory norms: Waterfowl hunter acceptance of changing duck bag limits

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Schroeder, Susan A.; Fulton, David C.; Lawrence, Jeffrey S.; Cordts, Steven D.

2014-01-01

Few studies have examined response to regulatory change over time, or addressed hunter attitudes about changes in hunting bag limits. This article explores Minnesota waterfowl hunters’ attitudes about duck bag limits, examining attitudes about two state duck bag limits that were initially more restrictive than the maximum set by the U.S. Fish and Wildlife Service (USFWS), but then increased to match federal limits. Results are from four mail surveys that examined attitudes about bag limits over time. Following two bag limit increases, a greater proportion of hunters rated the new bag limit “too high” and a smaller proportion rated it “too low.” Several years following the first bag limit increase, the proportion of hunters who indicated that the limit was “too high” had declined, suggesting hunter acceptance of the new regulation. Results suggest that waterfowl bag limits may represent legal norms that influence hunter attitudes and gain legitimacy over time.

Mental health perspectives of Hunter syndrome: Case reports of two biological siblings

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Kabir Garg

2016-01-01

Full Text Available Hunter syndrome is a rare X-linked recessive disorder caused by deficiency of the lysosomal enzyme iduronate-2-sulphatase, leading to progressive accumulation of a substance called glycosaminoglycans in nearly all cell types, tissues, and organs. Hunter syndrome presents with facial dysmorphism, airway diseases, skeletal defects, cardiomyopathies, and neuropsychiatric manifestations. Mental subnormality is a cardinal feature in Hunter syndrome. This is a progressive cognitive decline that is not amenable to enzyme replacement therapy. Due to progressive cognitive decline, training the children to improve the adaptive functioning is a challenge that creates immense stress for the caregivers. Patients with Hunter syndrome should undergo serial assessment of intellectual ability and may be trained accordingly.

75 FR 32877 - Financial Assistance: Wildlife Restoration, Sport Fish Restoration, Hunter Education and Safety

Science.gov (United States)

2010-06-10

... resources, aquatic-life forms, and sport fishing; and (e) develop responsible attitudes and ethics toward..., Sport Fish Restoration, Hunter Education and Safety AGENCY: Fish and Wildlife Service, Interior. ACTION... governing the Wildlife Restoration, Sport Fish Restoration, and Hunter Education and Safety (Enhanced Hunter...

Core Hunter 3: flexible core subset selection.

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De Beukelaer, Herman; Davenport, Guy F; Fack, Veerle

2018-05-31

Core collections provide genebank curators and plant breeders a way to reduce size of their collections and populations, while minimizing impact on genetic diversity and allele frequency. Many methods have been proposed to generate core collections, often using distance metrics to quantify the similarity of two accessions, based on genetic marker data or phenotypic traits. Core Hunter is a multi-purpose core subset selection tool that uses local search algorithms to generate subsets relying on one or more metrics, including several distance metrics and allelic richness. In version 3 of Core Hunter (CH3) we have incorporated two new, improved methods for summarizing distances to quantify diversity or representativeness of the core collection. A comparison of CH3 and Core Hunter 2 (CH2) showed that these new metrics can be effectively optimized with less complex algorithms, as compared to those used in CH2. CH3 is more effective at maximizing the improved diversity metric than CH2, still ensures a high average and minimum distance, and is faster for large datasets. Using CH3, a simple stochastic hill-climber is able to find highly diverse core collections, and the more advanced parallel tempering algorithm further increases the quality of the core and further reduces variability across independent samples. We also evaluate the ability of CH3 to simultaneously maximize diversity, and either representativeness or allelic richness, and compare the results with those of the GDOpt and SimEli methods. CH3 can sample equally representative cores as GDOpt, which was specifically designed for this purpose, and is able to construct cores that are simultaneously more diverse, and either are more representative or have higher allelic richness, than those obtained by SimEli. In version 3, Core Hunter has been updated to include two new core subset selection metrics that construct cores for representativeness or diversity, with improved performance. It combines and outperforms the

PALEOLITHIC HUNTER-GATHERERS' DIETARY PATTERNS ...

African Journals Online (AJOL)

Dr. Al-Domi

the main aspects of Paleolithic hunter-gatherers' dietary patterns and its main long-term ... Hence, people in developing countries have been exposed to certain ... as food habits, which prompted possible negative impacts on health status leading to ... costs [5, 7]. .... Agricultural revolution with efficient production of grains,.

How Do Hunter-Gatherer Children Learn Subsistence Skills? : A Meta-Ethnographic Review.

Science.gov (United States)

Lew-Levy, Sheina; Reckin, Rachel; Lavi, Noa; Cristóbal-Azkarate, Jurgi; Ellis-Davies, Kate

2017-12-01

Hunting and gathering is, evolutionarily, the defining subsistence strategy of our species. Studying how children learn foraging skills can, therefore, provide us with key data to test theories about the evolution of human life history, cognition, and social behavior. Modern foragers, with their vast cultural and environmental diversity, have mostly been studied individually. However, cross-cultural studies allow us to extrapolate forager-wide trends in how, when, and from whom hunter-gatherer children learn their subsistence skills. We perform a meta-ethnography, which allows us to systematically extract, summarize, and compare both quantitative and qualitative literature. We found 58 publications focusing on learning subsistence skills. Learning begins early in infancy, when parents take children on foraging expeditions and give them toy versions of tools. In early and middle childhood, children transition into the multi-age playgroup, where they learn skills through play, observation, and participation. By the end of middle childhood, most children are proficient food collectors. However, it is not until adolescence that adults (not necessarily parents) begin directly teaching children complex skills such as hunting and complex tool manufacture. Adolescents seek to learn innovations from adults, but they themselves do not innovate. These findings support predictive models that find social learning should occur before individual learning. Furthermore, these results show that teaching does indeed exist in hunter-gatherer societies. And, finally, though children are competent foragers by late childhood, learning to extract more complex resources, such as hunting large game, takes a lifetime.

Social networks and cooperation in hunter-gatherers.

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Apicella, Coren L; Marlowe, Frank W; Fowler, James H; Christakis, Nicholas A

2012-01-25

Social networks show striking structural regularities, and both theory and evidence suggest that networks may have facilitated the development of large-scale cooperation in humans. Here, we characterize the social networks of the Hadza, a population of hunter-gatherers in Tanzania. We show that Hadza networks have important properties also seen in modernized social networks, including a skewed degree distribution, degree assortativity, transitivity, reciprocity, geographic decay and homophily. We demonstrate that Hadza camps exhibit high between-group and low within-group variation in public goods game donations. Network ties are also more likely between people who give the same amount, and the similarity in cooperative behaviour extends up to two degrees of separation. Social distance appears to be as important as genetic relatedness and physical proximity in explaining assortativity in cooperation. Our results suggest that certain elements of social network structure may have been present at an early point in human history. Also, early humans may have formed ties with both kin and non-kin, based in part on their tendency to cooperate. Social networks may thus have contributed to the emergence of cooperation.

Drusen-like beneath retinal deposits in type II mesangiocapillary glomerulonephritis: a review

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Miguel Hage Amaro

2015-02-01

Full Text Available The aim of this paper is to do a review of Drusen-like beneath retinal deposits in type II mesangiocapillary glomerulonephritis. Drusenlike beneath retinal deposits in type II mesangiocapillary glomerulonephritis appear to develop at an early age, often second decade of life different of drusen from age-related macular degeneration (AMD.Long term follow-up of the cases in this disease shows in the most of them, no progression of the of drusen-like beneath retinal deposits in type II mesangiocapillary glomerulonefritis, the most of subjects retain good visual acuity and no specific treatment is indicated.

Ride, shoot, and call: wildlife use among contemporary urban hunters in Três Fronteiras, Brazilian Amazon

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Nathalie van Vliet

2015-09-01

Full Text Available Most bushmeat studies in the Amazon region focus on hunting patterns of indigenous populations in rural settings. Our study describes the existence of urban hunters in medium-sized towns. Using a variety of data collection methods, we describe the main socioeconomic characteristics of urban hunters in Benjamin Constant and Atalaia do Norte, Brazil. We analyze the patterns and motivations of urban hunters as well as the type of prey harvested and quantities traded. All interviewed hunters are caboclos, people of mixed Brazilian indigenous and European origins from rural areas who now live in urban and peri-urban areas. Living in these more populated spaces allows these hunters better market options for their harvest and allows them to alternate hunting with other economic activities. Only 29% of the interviewed hunters relied solely on hunting. In total, 11.6 tons of bushmeat were harvested (of which 97% was traded by four hunters during the monitoring period (60 days. The most hunted species were terecay (Podocnemis unifilis, curassow (Crax sp., paca (Cuniculus paca, and tapir (Tapirus terrestris. The ratio of bushmeat sold to that consumed, as well as the level of participation in the bushmeat market chain, allowed us to differentiate between specialized and diversified hunters. Specialized hunters sell 81% of the bushmeat caught to known wholesalers in the city. Diversified hunters sell 21% of their total catch to families, neighbors, or friends directly as fresh meat, avoiding intermediaries. For all hunters, hunting localities are associated with peri-urban roadways that are easily reached by motorbike or bicycle from the hunters' houses in the urban areas or city fringes. Our results show that urban hunters in medium-sized towns exemplify how traditional hunting systems can be adapted in the face of globalization, by living close to the market, at relatively manageable distances from hunting grounds, and using modern methods of

Cooperation and the evolution of hunter-gatherer storytelling.

Science.gov (United States)

Smith, Daniel; Schlaepfer, Philip; Major, Katie; Dyble, Mark; Page, Abigail E; Thompson, James; Chaudhary, Nikhil; Salali, Gul Deniz; Mace, Ruth; Astete, Leonora; Ngales, Marilyn; Vinicius, Lucio; Migliano, Andrea Bamberg

2017-12-05

Storytelling is a human universal. From gathering around the camp-fire telling tales of ancestors to watching the latest television box-set, humans are inveterate producers and consumers of stories. Despite its ubiquity, little attention has been given to understanding the function and evolution of storytelling. Here we explore the impact of storytelling on hunter-gatherer cooperative behaviour and the individual-level fitness benefits to being a skilled storyteller. Stories told by the Agta, a Filipino hunter-gatherer population, convey messages relevant to coordinating behaviour in a foraging ecology, such as cooperation, sex equality and egalitarianism. These themes are present in narratives from other foraging societies. We also show that the presence of good storytellers is associated with increased cooperation. In return, skilled storytellers are preferred social partners and have greater reproductive success, providing a pathway by which group-beneficial behaviours, such as storytelling, can evolve via individual-level selection. We conclude that one of the adaptive functions of storytelling among hunter gatherers may be to organise cooperation.

Evaluation of PHI Hunter in Natural Language Processing Research.

Science.gov (United States)

Redd, Andrew; Pickard, Steve; Meystre, Stephane; Scehnet, Jeffrey; Bolton, Dan; Heavirland, Julia; Weaver, Allison Lynn; Hope, Carol; Garvin, Jennifer Hornung

2015-01-01

We introduce and evaluate a new, easily accessible tool using a common statistical analysis and business analytics software suite, SAS, which can be programmed to remove specific protected health information (PHI) from a text document. Removal of PHI is important because the quantity of text documents used for research with natural language processing (NLP) is increasing. When using existing data for research, an investigator must remove all PHI not needed for the research to comply with human subjects' right to privacy. This process is similar, but not identical, to de-identification of a given set of documents. PHI Hunter removes PHI from free-form text. It is a set of rules to identify and remove patterns in text. PHI Hunter was applied to 473 Department of Veterans Affairs (VA) text documents randomly drawn from a research corpus stored as unstructured text in VA files. PHI Hunter performed well with PHI in the form of identification numbers such as Social Security numbers, phone numbers, and medical record numbers. The most commonly missed PHI items were names and locations. Incorrect removal of information occurred with text that looked like identification numbers. PHI Hunter fills a niche role that is related to but not equal to the role of de-identification tools. It gives research staff a tool to reasonably increase patient privacy. It performs well for highly sensitive PHI categories that are rarely used in research, but still shows possible areas for improvement. More development for patterns of text and linked demographic tables from electronic health records (EHRs) would improve the program so that more precise identifiable information can be removed. PHI Hunter is an accessible tool that can flexibly remove PHI not needed for research. If it can be tailored to the specific data set via linked demographic tables, its performance will improve in each new document set.

Guidelines for diagnosis and treatment of Hunter Syndrome for clinicians in Latin America

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Roberto Giugliani

2014-06-01

Full Text Available This review aims to provide clinicians in Latin America with the most current information on the clinical aspects, diagnosis, and management of Hunter syndrome, a serious and progressive disease for which specific treatment is available. Hunter syndrome is a genetic disorder where iduronate-2-sulfatase (I2S, an enzyme that degrades glycosaminoglycans, is absent or deficient. Clinical manifestations vary widely in severity and involve multiple organs and tissues. An attenuated and a severe phenotype are recognized depending on the degree of cognitive impairment. Early diagnosis is vital for disease management. Clinical signs common to children with Hunter syndrome include inguinal hernia, frequent ear and respiratory infections, facial dysmorphisms, macrocephaly, bone dysplasia, short stature, sleep apnea, and behavior problems. Diagnosis is based on screening urinary glycosaminoglycans and confirmation by measuring I2S activity and analyzing I2S gene mutations. Idursulfase (recombinant I2S (Elaprase®, Shire enzyme replacement therapy (ERT, designed to address the underlying enzyme deficiency, is approved treatment and improves walking capacity and respiratory function, and reduces spleen and liver size and urinary glycosaminoglycan levels. Additional measures, responding to the multi-organ manifestations, such as abdominal/inguinal hernia repair, carpal tunnel surgery, and cardiac valve replacement, should also be considered. Investigational treatment options such as intrathecal ERT are active areas of research, and bone marrow transplantation is in clinical practice. Communication among care providers, social workers, patients and families is essential to inform and guide their decisions, establish realistic expectations, and assess patients' responses.

Humans as predators: an overview of predation strategies of hunters with contrasting motivational drivers

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Fredrik Dalerum

2018-01-01

Full Text Available Predator-prey theory suggests that generalist predators are linked to demographic stability of prey whereas specialists are destabilizing. We overview the demographic consequences of different predation strategies and hypothesize that subsistence hunting occurs opportunistically, persecution hunters behave like specialist predators, and recreational hunters behave like generalist predators. Under this hypothesis, persecution hunting would have destabilizing effects, whereas the effects of subsistence and recreational hunting would be neutral or stabilizing. We found poor empirical support for this hypothesis, but there was scarce empirical data. Recreational hunters mainly hunted opportunistically and hunting as managed persecution followed a type III functional response, i.e. with low hunting intensity at low game abundances and a switch to an increased intensity at some level of abundance. We suggest that recreational hunters have limited destabilizing effects on game populations and that hunting may be an ineffective way of complete the removal of invasive species. We urge for further studies quantifying the responses of hunters to game abundances, in particular studies evaluating the responses of subsistence hunters and illegal persecution.

The Enchanted Hunters in Nabokov’s Lolita

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Justine Shu- Ting Kao

2017-06-01

Full Text Available In Nabokov’s Lolita, Humbert Humbert’s The Enchanted Hunters, as a quest for love, aims to reconstruct a felicitous world or integrate various fragmentary details into an organic unity that revives a lost love, experiencing it on the basis of irony, and revealing a simulation of the desire, violence, and despondency which have been expressed in myths of nymphs and Persephone. The protagonist never reaches this unity, but his narrative of erotic and romantic love reveals him as a pathetic addict engaged in mechanical reproduction related to the phenomena of desire, seduction, violence, and sex. His The Enchanted Hunters does not simulate what he expects of his childhood love with Annabel; rather, it simulates the erotic imagination suggested in Mary D. Sheriff’s term “nymphomania,” in which artists fall degenerately to a model of tragedy. Keywords: simulation, nymph, nymphomania, The Enchanted Hunters The Enchanted Hunters in Nabokov’s Lolita refers to the name of a hotel and the title of a play. This seeming coincidence is actually not coincidental: Nabokov weaves a story concerning a pedophile’s seduction of a prepubescent child into a “story within a story,” in which the girl is imagined as a seducer who bewitches a number of hunters. Just as the girl in the play is a figment of a poet’s imagination, so Lolita in the novel Lolita is an imaginary production of a middle-aged pedophile. Yet Lolita is not so much a novel revealing guilt and mental disorder, but a mélange of art and reality, or more specifically, it is about a coinage in which the author fabricates art and myth in real life. Parallel to the protagonist who simulates what he expects of his childhood love, Annabel, in the form of the nymphet, Lolita, Nabokov replicates the beauty of butterflies in the pursuit of beauty and immortality, and develops the world of art with a pathetic tone whereby we gradually perceive a simulation of the desire, violence, and

Influence of Age and Educational Level on the Behavior of Hunters in Vojvodina Province (Serbia

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Vladimir Marković

2011-07-01

Full Text Available Education as an important factor in the development of economy has a major impact on the development of hunting and hunting tourism. In this research, it has conducted a survey of hunters from the territory of Vojvodina Province regarding their attitude and motives for hunting, importance of education, importance of GIS in hunting, poaching as well as their level of hunting ethics. Using SPSS program, it was cross-referenced the individual responses in relation to age category and level of education. The results show that the youngest hunters (18 to 35 years compared to middle age hunters (35-59 years and old hunters (over 60 visit hunting events more, they are the most informed about GIS and they are most willing to learn about these technologies. The number of hunters that took part in the poaching is proportional with their level of education, so that most hunters that participate in poaching hold a university degree. However, hunters holding a university degree in the highest percentage believe that GIS can contribute to the development of hunting largely, and are willing to participate in training.

Hunter-gatherer genomic diversity suggests a southern African origin for modern humans.

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Henn, Brenna M; Gignoux, Christopher R; Jobin, Matthew; Granka, Julie M; Macpherson, J M; Kidd, Jeffrey M; Rodríguez-Botigué, Laura; Ramachandran, Sohini; Hon, Lawrence; Brisbin, Abra; Lin, Alice A; Underhill, Peter A; Comas, David; Kidd, Kenneth K; Norman, Paul J; Parham, Peter; Bustamante, Carlos D; Mountain, Joanna L; Feldman, Marcus W

2011-03-29

Africa is inferred to be the continent of origin for all modern human populations, but the details of human prehistory and evolution in Africa remain largely obscure owing to the complex histories of hundreds of distinct populations. We present data for more than 580,000 SNPs for several hunter-gatherer populations: the Hadza and Sandawe of Tanzania, and the ≠Khomani Bushmen of South Africa, including speakers of the nearly extinct N|u language. We find that African hunter-gatherer populations today remain highly differentiated, encompassing major components of variation that are not found in other African populations. Hunter-gatherer populations also tend to have the lowest levels of genome-wide linkage disequilibrium among 27 African populations. We analyzed geographic patterns of linkage disequilibrium and population differentiation, as measured by F(ST), in Africa. The observed patterns are consistent with an origin of modern humans in southern Africa rather than eastern Africa, as is generally assumed. Additionally, genetic variation in African hunter-gatherer populations has been significantly affected by interaction with farmers and herders over the past 5,000 y, through both severe population bottlenecks and sex-biased migration. However, African hunter-gatherer populations continue to maintain the highest levels of genetic diversity in the world.

PLANET HUNTERS: ASSESSING THE KEPLER INVENTORY OF SHORT-PERIOD PLANETS

International Nuclear Information System (INIS)

Schwamb, Megan E.; Lintott, Chris J.; Lynn, Stuart; Smith, Arfon M.; Simpson, Robert J.; Fischer, Debra A.; Giguere, Matthew J.; Brewer, John M.; Parrish, Michael; Schawinski, Kevin

2012-01-01

We present the results from a search of data from the first 33.5 days of the Kepler science mission (Quarter 1) for exoplanet transits by the Planet Hunters citizen science project. Planet Hunters enlists members of the general public to visually identify transits in the publicly released Kepler light curves via the World Wide Web. Over 24,000 volunteers reviewed the Kepler Quarter 1 data set. We examine the abundance of ≥2 R ⊕ planets on short-period ( ⊕ Planet Hunters ≥85% efficient at identifying transit signals for planets with periods less than 15 days for the Kepler sample of target stars. Our high efficiency rate for simulated transits along with recovery of the majority of Kepler ≥4 R ⊕ planets suggests that the Kepler inventory of ≥4 R ⊕ short-period planets is nearly complete.

Drivers of change in hunter offtake and hunting strategies in Sendje, Equatorial Guinea.

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Gill, David J C; Fa, John E; Rowcliffe, J Marcus; Kümpel, Noëlle F

2012-12-01

Economic development in Africa is expected to increase levels of bushmeat hunting through rising demand for meat and improved transport infrastructure. However, few studies have tracked long-term changes in hunter behavior as a means of testing this prediction. We evaluated changes in hunter behavior in a rural community in Equatorial Guinea over a period of rapid national economic growth, during which time road access to the regional capital greatly improved. We conducted offtake surveys (Supporting Information) over 3 7-week periods at the same time of year in 1998, 2003, and 2010 and conducted hunter and household interviews (Supporting Information) in 2003 and 2010. We tested whether relations existed among catch, hunting effort, hunting strategy, and income earned through hunting and other livelihoods in 2003 and 2010. Although village offtake increased from 1775 kg in 1998 to 4172 kg in 2003, it decreased in 2010 to 1361 kg. Aggregate catch per unit effort (i.e., number of carcasses caught per hunter and per trap) decreased from 2003 to 2010, and the majority of hunters reported a decrease in abundance of local fauna. Although these results are indicative of unsustainable hunting, cumulative changes in offtake and catch per unit effort were driven by a contraction in the total area hunted following an out-migration of 29 of the village's hunters, most of whom left to gain employment in the construction industry, after 2003. Hunters operating in both 2003 and 2010 hunted closer to the village because an increased abundance of elephants posed a danger and because they desired to earn income through other activities. Our study provides an example of national economic development contributing to a reduction in the intensity and extent of hunting. ©2012 Society for Conservation Biology.

Hunter-gatherers in southeast Asia: from prehistory to the present.

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Higham, Charles

2013-01-01

Anatomically modern hunter-gatherers expanded from Africa into Southeast Asia at least 50,000 years ago, where they probably encountered and interacted with populations of Homo erectus and Homo floresiensis and the recently discovered Denisovans. Simulation studies suggest that these hunter-gatherers may well have followed a coastal route that ultimately led to the settlement of Sahul, while archaeology confirms that they also crossed significant seas and explored well into the interior. They also adapted to marked environmental changes that alternated between relatively cool and dry conditions and warmer, wetter interludes. During the former, the sea fell by up to 120 m below its present level, which opened up a vast low-lying area known as Sundaland. Three principal alignments can be identified: the first involved the occupation of rock shelters in upland regions, the second has identified settlement on broad riverine floodplains, and the last concentrated on the raised beaches formed from about five millennia ago when the sea level was elevated above its present position. This cultural sequence was dislocated about 4 kya when rice and millet farmers infiltrated the lowlands of Southeast Asia ultimately from the Yangtze River valley. It is suggested that this led to two forms of interaction. In the first, the indigenous hunter-gatherers integrated with intrusive Neolithic communities and, while losing their cultural identity, contributed their genes to the present population of Southeast Asia. In the second, hunter-gatherers withdrew to rainforest refugia and, through selective pressures inherent in such an environment, survived as the small-bodied, dark-skinned humans found to this day in the Philippines, Peninsular Malaysia and Thailand, and the Andaman Islands. Beyond the impact of expansive rice farmers in Melanesia and Australia, hunter-gatherers continued to dominate until they encountered European settlement. Copyright © 2013 Wayne State University Press

Future Discounting in Congo Basin Hunter-Gatherers Declines with Socio-Economic Transitions.

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Gul Deniz Salali

Full Text Available Humans have a tendency to discount the future; that is we value small, short-term rewards over larger, long-term rewards. The degree of future discounting, however, changes in response to socio-ecological factors. Here, we study Mbendjele BaYaka hunter-gatherers of northern Congo and their farmer neighbours to investigate adaptations in inter-temporal preferences in humans. We argue that in immediate-return systems, where food storage is absent and egalitarianism is enforced through levelling mechanisms, future discounting is an adaptive strategy to prevent wealth accumulation and the emergence of hierarchies. This ensures food sharing and allows for survival in unpredictable environments where there is risk of an energy shortfall. On the other hand, when food storage is made possible by the emergence of agriculture or as seen in some delayed-return hunter-gatherer populations, wealth accumulation, hierarchies and lower discount rates become the adaptive strategy. Therefore, individuals in immediate-return, egalitarian societies will discount the future more than those in non-egalitarian, delayed-return societies. Consistent with the predictions we found that market integration and socio-economic transitions decrease the future discounting in Mbendjele hunter-gatherers. Our measures of socio-economic differences marked this transition in hunter-gatherers living in a logging town. The degree of future-discounting was the same between more market-integrated hunter-gatherers and their farmer neighbours.

Hunter College Dance Therapy Masters Program.

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Schmais, Claire; White, Elissa Q.

Described is development of the Hunter College dance therapy 18-month 30-credit masters program involving 33 adult students, (in two classes beginning in 1971 and 1972), an educational model, internship in psychiatric institutions, and preparation of instructional materials. The dance therapist is said to incorporate the psychiatric patient's…

Wild-harvested venison yields and sharing by Michigan deer hunters

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Goguen, Amber D.; Riley, Shawn J.; Organ, John F.; Rudolph, Brent A.

2018-01-01

An increased societal focus on wildlife as food and recent policy deliberations regarding legal markets for wild-harvested meat are encouraging wildlife managers and researchers to examine the amount, use, and distribution of meat yielded through recreational hunting. We used responses to questions on the Michigan Deer Harvest Study to estimate the maximum yield of edible venison and assess hunters’ sharing behaviors. We estimated 11,402–14,473 metric tons of edible venison were procured during the 2013 hunting season. Of hunters who harvested a deer, 85% shared their venison. Hunters who shared did so with an average of 5.6 people (SD = 4.5). Sharing occurred most frequently within tight social networks: members of hunters’ households (69%), relatives (52%), and friends, neighbors, or coworkers (50%). In the absence of legal markets, venison is distributed widely by hunters and greatly amplifies the number of people benefiting from hunting. Nonetheless, we also identified the potential breadth of exposure to disease or contaminants from wild-harvested meat.

Anterior Hypopituitarism and Treatment Response in Hunter Syndrome: A Comparison of Two Patients

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Munier A. Nour

2016-01-01

Full Text Available Hypopituitarism is a clinically important diagnosis and has not previously been reported in Hunter syndrome. We contrast two cases with anatomic pituitary anomalies: one with anterior panhypopituitarism and the other with intact pituitary function. Patient 1, a 10-year-old boy with Hunter syndrome, was evaluated for poor growth and an ectopic posterior pituitary gland. Endocrine testing revealed growth hormone (GH deficiency, secondary adrenal insufficiency, and tertiary hypothyroidism. An improvement in growth velocity with hormone replacement (GH, thyroxine, and corticosteroid was seen; however, final adult height remained compromised. Patient 2, a 13-year-old male with Hunter syndrome, was evaluated for growth failure. He had a large empty sella turcica with posteriorly displaced pituitary. Functional endocrine testing was normal and a trial of GH-treatment yielded no significant effect. Panhypopituitarism associated with pituitary anomalies has not been previously reported in Hunter syndrome and was an incidental finding of significant clinical importance. In the setting of documented anterior hypopituitarism, while hormone replacement improved growth velocity, final height remained impaired. In patient 2 with equivocal GH-testing results, treatment had no effect on linear growth. These cases highlight the importance of careful clinical assessment in Hunter syndrome and that judicious hormone replacement may be indicated in individual cases.

Inferring the demographic history of African farmers and pygmy hunter-gatherers using a multilocus resequencing data set.

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Etienne Patin

2009-04-01

Full Text Available The transition from hunting and gathering to farming involved a major cultural innovation that has spread rapidly over most of the globe in the last ten millennia. In sub-Saharan Africa, hunter-gatherers have begun to shift toward an agriculture-based lifestyle over the last 5,000 years. Only a few populations still base their mode of subsistence on hunting and gathering. The Pygmies are considered to be the largest group of mobile hunter-gatherers of Africa. They dwell in equatorial rainforests and are characterized by their short mean stature. However, little is known about the chronology of the demographic events-size changes, population splits, and gene flow--ultimately giving rise to contemporary Pygmy (Western and Eastern groups and neighboring agricultural populations. We studied the branching history of Pygmy hunter-gatherers and agricultural populations from Africa and estimated separation times and gene flow between these populations. We resequenced 24 independent noncoding regions across the genome, corresponding to a total of approximately 33 kb per individual, in 236 samples from seven Pygmy and five agricultural populations dispersed over the African continent. We used simulation-based inference to identify the historical model best fitting our data. The model identified included the early divergence of the ancestors of Pygmy hunter-gatherers and farming populations approximately 60,000 years ago, followed by a split of the Pygmies' ancestors into the Western and Eastern Pygmy groups approximately 20,000 years ago. Our findings increase knowledge of the history of the peopling of the African continent in a region lacking archaeological data. An appreciation of the demographic and adaptive history of African populations with different modes of subsistence should improve our understanding of the influence of human lifestyles on genome diversity.

Estimating Net Primary Productivity Beneath Snowpack Using Snowpack Radiative Transfer Modeling and Global Satellite Data

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Barber, D. E.; Peterson, M. C.

2002-05-01

Sufficient photosynthetically active radiation (PAR) penetrates snow for plants to grow beneath snowpack during late winter or early spring in tundra ecosystems. During the spring in this ecosystem, the snowpack creates an environment with higher humidity and less variable and milder temperatures than on the snow-free land. Under these conditions, the amount of PAR available is likely to be the limiting factor for plant growth. Current methods for determining net primary productivity (NPP) of tundra ecosystems do not account for this plant growth beneath snowpack, apparently resulting in underestimating plant production there. We are currently in the process of estimating the magnitude of this early growth beneath snow for tundra ecosystems. Our method includes a radiative transfer model that simulates diffuse and direct PAR penetrating snowpack based on downwelling PAR values and snow depth data from global satellite databases. These PAR levels are convolved with plant growth for vegetation that thrives beneath snowpacks, such as lichen. We expect to present the net primary production for Cladonia species (a common Arctic lichen) that has the capability of photosynthesizing at low temperatures beneath snowpack. This method may also be used to study photosynthesis beneath snowpacks in other hardy plants. Lichens are used here as they are common in snow-covered regions, flourish under snowpack, and provide an important food source for tundra herbivores (e.g. caribou). In addition, lichens are common in arctic-alpine environments and our results can be applied to these ecosystems as well. Finally, the NPP of lichen beneath snowpack is relatively well understood compared to other plants, making it ideal vegetation for this first effort at estimating the potential importance of photosynthesis at large scales. We are examining other candidate plants for their photosynthetic potential beneath snowpack at this time; however, little research has been done on this topic. We

Clarifying beliefs underlying hunter intentions to support a ban on lead shot

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Schroeder, Susan A.; Fulton, David C.; Doncarlos, Kathy

2016-01-01

Shot from hunting adds toxic lead to environments worldwide. Existing lead shot regulations have been instituted with little understanding of hunter beliefs and attitudes. This study applied the Theory of Reasoned Action, using a multilevel, multivariate approach, to clarify how positive and negative beliefs relate to attitudes about a ban on lead shot. Structure coefficients and commonality analysis were employed to further examine relationships between beliefs and attitudes. Results suggest that while both positive and negative outcomes influence attitudes, positive outcomes were more influential for supporters and negative beliefs for opposers. Management may need to focus on the results from hunters who indicated that they would be unlikely to support a ban, as these hunters include those who may actively oppose additional efforts to regulate lead.

Sub-crustal seismic activity beneath Klyuchevskoy Volcano

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Carr, M. J.; Droznina, S.; Levin, V. L.; Senyukov, S.

2013-12-01

Seismic activity is extremely vigorous beneath the Klyuchevskoy Volcanic Group (KVG). The unique aspect is the distribution in depth. In addition to upper-crustal seismicity, earthquakes take place at depths in excess of 20 km. Similar observations are known in other volcanic regions, however the KVG is unique in both the number of earthquakes and that they occur continuously. Most other instances of deep seismicity beneath volcanoes appear to be episodic or transient. Digital recording of seismic signals started at the KVG in early 2000s.The dense local network reliably locates earthquakes as small as ML~1. We selected records of 20 earthquakes located at depths over 20 km. Selection was based on the quality of the routine locations and the visual clarity of the records. Arrivals of P and S waves were re-picked, and hypocentral parameters re-established. Newl locations fell within the ranges outlined by historical seismicity, confirming the existence of two distinct seismically active regions. A shallower zone is at ~20 km depth, and all hypocenters are to the northeast of KVG, in a region between KVG and Shiveluch volcano. A deeper zone is at ~30 km, and all hypocenters cluster directly beneath the edifice of the Kyuchevskoy volcano. Examination of individual records shows that earthquakes in both zones are tectonic, with well-defined P and S waves - another distinction of the deep seismicity beneath KVG. While the upper seismic zone is unquestionably within the crust, the provenance of the deeper earthquakes is enigmatic. The crustal structure beneath KVG is highly complex, with no agreed-upon definition of the crust-mantle boundary. Rather, a range of values, from under 30 to over 40 km, exists in the literature. Similarly, a range of velocity structures has been reported. Teleseismic receiver functions (RFs) provide a way to position the earthquakes with respect to the crust-mantle boundary. We compare the differential travel times of S and P waves from deep

An examination of gender bias on the eighth-grade MEAP science test as it relates to the Hunter Gatherer Theory of Spatial Sex Differences

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Armstrong-Hall, Judy Gail

The purpose of this study was to apply the Hunter-Gatherer Theory of sex spatial skills to responses to individual questions by eighth grade students on the Science component of the Michigan Educational Assessment Program (MEAP) to determine if sex bias was inherent in the test. The Hunter-Gatherer Theory on Spatial Sex Differences, an original theory, that suggested a spatial dimorphism concept with female spatial skill of pattern recall of unconnected items and male spatial skills requiring mental movement. This is the first attempt to apply the Hunter-Gatherer Theory on Spatial Sex Differences to a standardized test. An overall hypothesis suggested that the Hunter-Gatherer Theory of Spatial Sex Differences could predict that males would perform better on problems involving mental movement and females would do better on problems involving the pattern recall of unconnected items. Responses to questions on the 1994-95 MEAP requiring the use of male spatial skills and female spatial skills were analyzed for 5,155 eighth grade students. A panel composed of five educators and a theory developer determined which test items involved the use of male and female spatial skills. A MANOVA, using a random sample of 20% of the 5,155 students to compare male and female correct scores, was statistically significant, with males having higher scores on male spatial skills items and females having higher scores on female spatial skills items. Pearson product moment correlation analyses produced a positive correlation for both male and female performance on both types of spatial skills. The Hunter-Gatherer Theory of Spatial Sex Differences appears to be able to predict that males could perform better on the problems involving mental movement and females could perform better on problems involving the pattern recall of unconnected items. Recommendations for further research included: examination of male/female spatial skill differences at early elementary and high school levels to

Does Lateral Transmission Obscure Inheritance in Hunter-Gatherer Languages?

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Bowern, Claire; Epps, Patience; Gray, Russell; Hill, Jane; Hunley, Keith; McConvell, Patrick; Zentz, Jason

2011-01-01

In recent years, linguists have begun to increasingly rely on quantitative phylogenetic approaches to examine language evolution. Some linguists have questioned the suitability of phylogenetic approaches on the grounds that linguistic evolution is largely reticulate due to extensive lateral transmission, or borrowing, among languages. The problem may be particularly pronounced in hunter-gatherer languages, where the conventional wisdom among many linguists is that lexical borrowing rates are so high that tree building approaches cannot provide meaningful insights into evolutionary processes. However, this claim has never been systematically evaluated, in large part because suitable data were unavailable. In addition, little is known about the subsistence, demographic, ecological, and social factors that might mediate variation in rates of borrowing among languages. Here, we evaluate these claims with a large sample of hunter-gatherer languages from three regions around the world. In this study, a list of 204 basic vocabulary items was collected for 122 hunter-gatherer and small-scale cultivator languages from three ecologically diverse case study areas: northern Australia, northwest Amazonia, and California and the Great Basin. Words were rigorously coded for etymological (inheritance) status, and loan rates were calculated. Loan rate variability was examined with respect to language area, subsistence mode, and population size, density, and mobility; these results were then compared to the sample of 41 primarily agriculturalist languages in [1]. Though loan levels varied both within and among regions, they were generally low in all regions (mean 5.06%, median 2.49%, and SD 7.56), despite substantial demographic, ecological, and social variation. Amazonian levels were uniformly very low, with no language exhibiting more than 4%. Rates were low but more variable in the other two study regions, in part because of several outlier languages where rates of borrowing were

Imaging Lithospheric-scale Structure Beneath Northern Altiplano in Southern Peru and Northern Bolivia

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Kumar, A.; Wagner, L. S.; Beck, S. L.; Zandt, G.; Long, M. D.

2014-12-01

The northern Altiplano plateau of southern Peru and northern Bolivia is one of the highest topographic features on the Earth, flanked by Western and Eastern Cordillera along its margin. It has strongly influenced the local and far field lithospheric deformation since the early Miocene (Masek et al., 1994). Previous studies have emphasized the importance of both the crust and upper mantle in the evolution of Altiplano plateau (McQuarrie et al., 2005). Early tomographic and receiver function studies, south of 16° S, show significant variations in the crust and upper mantle properties in both perpendicular and along strike direction of the Altiplano plateau (Dorbath et. al., 1993; Myers et al., 1998; Beck and Zandt, 2002). In order to investigate the nature of subsurface lithospheric structure below the northern Altiplano, between 15-18° S, we have determined three-dimensional seismic tomography models for Vp and Vs using P and S-wave travel time data from two recently deployed local seismic networks of CAUGHT and PULSE. We also used data from 8 stations from the PERUSE network (PERU Subduction Experiment). Our preliminary tomographic models show a complex variation in the upper mantle velocity structure with depth, northwest and southeast of lake Titicaca. We see the following trend, at ~85 km depth, northwest of lake Titicaca: low Vp and Vs beneath the Western Cordillera, high Vs beneath the Altiplano and low Vp and Vs beneath the Eastern Cordillera. This low velocity anomaly, beneath Eastern Cordillera, seems to coincide with Kimsachata, a Holocene volcano in southern Peru. At depth greater than ~85 km: we find high velocity anomaly beneath the Western Cordillera and low Vs beneath the Altiplano. This high velocity anomaly, beneath Western Cordillera, coincides with the well-located Wadati-Benioff zone seismicity and perhaps represents the subducting Nazca slab. On the southeast of lake Titicaca, in northern Bolivia, we see a consistently high velocity anomaly

Comparing Road-Kill Datasets from Hunters and Citizen Scientists in a Landscape Context

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Florian Heigl

2016-10-01

Full Text Available Road traffic has severe effects on animals, especially when road-kills are involved. In many countries, official road-kill data are provided by hunters or police; there are also road-kill observations reported by citizen scientists. The aim of the current study was to test whether road-kill reports by hunters stem from similar landscapes than those reported by citizen scientists. We analysed the surrounding landscapes of 712 road-kill reportings of European hares in the province of Lower Austria. Our data showed that road-killed hares reported both by hunters and citizens are predominantly surrounded by arable land. No difference of hedges and solitary trees could be found between the two datasets. However, significant differences in landcover classes and surrounding road networks indicate that hunters’ and citizen scientists’ data are different. Hunters reported hares from landscapes with significantly higher percentages of arable land, and greater lengths of secondary roads. In contrast, citizens reported hares from landscapes with significantly higher percentages of urban or industrial areas and greater lengths of motorways, primary roads, and residential roads. From this we argue that hunters tend to report data mainly from their hunting areas, whereas citizens report data during their daily routine on the way to/from work. We conclude that a citizen science approach is an important source for road-kill data when used in addition to official data with the aim of obtaining an overview of road-kill events on a landscape scale.

"The Deer Hunter": Rhetoric of the Warrior.

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Rushing, Janice Hocker; Frentz, Thomas S.

A psychological/ritual model of criticism is used to examine the movie "The Deer Hunter" as a rhetorical event in which males undergo psychological change through their war and postwar experiences. The critical model depends on understanding a Jungian interpretation of the human psyche, the form and function of initiation rituals, and…

Profile of idursulfase for the treatment of Hunter syndrome

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Sestito S

2015-07-01

Full Text Available Simona Sestito, Ferdinando Ceravolo, Michele Grisolia, Elisa Pascale, Licia Pensabene, Daniela Concolino Department of Pediatrics, University Magna Graecia of Catanzaro, Catanzaro, Italy Abstract: Mucopolysaccharidosis type II (MPS II; Hunter syndrome is a rare X-linked lysosomal storage disorder caused by deficiency of the enzyme iduronate-2-sulfatase (IDS. Enzyme replacement therapy (ERT with recombinant human IDS, available since 2005, is currently the most appropriate treatment for this progressive, multisystemic, chronic, and life-threatening disease. Efficacy and safety of therapy with idursulfase have been assessed in several clinical trials, and confirmed in many clinical reports. Long-term follow-up of patients receiving ERT has demonstrated the importance of an early onset of treatment with idursulfase, before irreversible pathological changes occur. Intravenously administered idursulfase is not able to cross the blood–brain barrier, so neurological signs and symptoms cannot benefit from ERT, still remaining a major challenge in the treatment of MPS II. Keywords: MPS II, glycosaminoglycans, enzyme replacement therapy, ERT

Hunter versus CIE color measurement systems for analysis of milk-based beverages.

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Cheng, Ni; Barbano, David M; Drake, Mary Anne

2018-06-01

The objective of our work was to determine the differences in sensitivity of Hunter and International Commission on Illumination (CIE) methods at 2 different viewer angles (2 and 10°) for measurement of whiteness, red/green, and blue/yellow color of milk-based beverages over a range of composition. Sixty combinations of milk-based beverages were formulated (2 replicates) with a range of fat level from 0.2 to 2%, true protein level from 3 to 5%, and casein as a percent of true protein from 5 to 80% to provide a wide range of milk-based beverage color. In addition, commercial skim, 1 and 2% fat high-temperature, short-time pasteurized fluid milks were analyzed. All beverage formulations were HTST pasteurized and cooled to 4°C before analysis. Color measurement viewer angle (2 vs. 10°) had very little effect on objective color measures of milk-based beverages with a wide range of composition for either the Hunter or CIE color measurement system. Temperature (4, 20, and 50°C) of color measurement had a large effect on the results of color measurement in both the Hunter and CIE measurement systems. The effect of milk beverage temperature on color measurement results was the largest for skim milk and the least for 2% fat milk. This highlights the need for proper control of beverage serving temperature for sensory panel analysis of milk-based beverages with very low fat content and for control of milk temperature when doing objective color analysis for quality control in manufacture of milk-based beverages. The Hunter system of color measurement was more sensitive to differences in whiteness among milk-based beverages than the CIE system, whereas the CIE system was much more sensitive to differences in yellowness among milk-based beverages. There was little difference between the Hunter and CIE system in sensitivity to green/red color of milk-based beverages. In defining milk-based beverage product specifications for objective color measures for dairy product

The formation of fire residues associated with hunter-gatherers in humid tropical environments: A geo-ethnoarchaeological perspective

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Friesem, David E.; Lavi, Noa; Madella, Marco; Boaretto, Elisabetta; Ajithparsad, P.; French, Charles

2017-09-01

Tropical forests have been an important human habitat and played a significant role in early human dispersal and evolution. Likewise, the use of fire, besides being one of the exceptional characteristics of humans, serves as a marker for human evolution. While the use of fire by prehistoric hunter-gatherers is relatively well documented in arid and temperate environments, the archaeological evidence in humid tropical environment is to date very limited. We first review the archaeological evidence for hunter-gatherer use of fire in humid tropical environments and suggest that better understanding of formation processes is required. We present a geo-ethnoarchaeological study from South India, involving ethnography, excavations and laboratory-based analyses in order to build a new framework to study fire residues in humid tropical forests associated with hunter-gatherer's use of fire. Ethnographic observations point to a dynamic and ephemeral use of hearths. Hearths location were dictated by the social and ever-changing social dynamics of the site. The hearths deposited small amount of residues which were later swept on a daily basis, re-depositing ash and charcoal in waste areas and leaving only a microscopic signal in the original location. Particular acidic conditions and intensive biological activity within tropical sediments result in the complete dissolution of ash and bones while favouring the preservation of charcoal and phytoliths. Consequently, the identification of fire residues in humid tropical forests and the reconstruction of the human use of fire must involve multi-proxy microscopic analysis to detect its micro-signatures.

Fiber-optic displacement sensors on the Hunters Trophy UGT impulse gauge experiments

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Green, R.E.L.; Poutiatine, A.I.

1995-03-01

As part of a program to develop gauges for measurement of various mechanical properties in hostile environments, the authors fielded purely optical displacement sensors at the ends of long fiber-optic cables as supplements to the regular displacement sensors of four impulse gauges fielded as part of a materials study on the Hunters Trophy underground effects test at the Nevada Test Site. These fiber-optic sensor systems and their performance on the Hunters Trophy test are described in this report.

Targeting hunter distribution based on host resource selection and kill sites to manage disease risk.

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Dugal, Cherie J; van Beest, Floris M; Vander Wal, Eric; Brook, Ryan K

2013-10-01

Endemic and emerging diseases are rarely uniform in their spatial distribution or prevalence among cohorts of wildlife. Spatial models that quantify risk-driven differences in resource selection and hunter mortality of animals at fine spatial scales can assist disease management by identifying high-risk areas and individuals. We used resource selection functions (RSFs) and selection ratios (SRs) to quantify sex- and age-specific resource selection patterns of collared (n = 67) and hunter-killed (n = 796) nonmigratory elk (Cervus canadensis manitobensis) during the hunting season between 2002 and 2012, in southwestern Manitoba, Canada. Distance to protected area was the most important covariate influencing resource selection and hunter-kill sites of elk (AICw = 1.00). Collared adult males (which are most likely to be infected with bovine tuberculosis (Mycobacterium bovis) and chronic wasting disease) rarely selected for sites outside of parks during the hunting season in contrast to adult females and juvenile males. The RSFs showed selection by adult females and juvenile males to be negatively associated with landscape-level forest cover, high road density, and water cover, whereas hunter-kill sites of these cohorts were positively associated with landscape-level forest cover and increasing distance to streams and negatively associated with high road density. Local-level forest was positively associated with collared animal locations and hunter-kill sites; however, selection was stronger for collared juvenile males and hunter-killed adult females. In instances where disease infects a metapopulation and eradication is infeasible, a principle goal of management is to limit the spread of disease among infected animals. We map high-risk areas that are regularly used by potentially infectious hosts but currently underrepresented in the distribution of kill sites. We present a novel application of widely available data to target hunter distribution based on host resource

Salinity and resource management in the Hunter Valley

Energy Technology Data Exchange (ETDEWEB)

Creelman, R.A.; Cooke, R.; Simons, M. [RA Creelman & Associates (Australia)

1995-08-01

If excess water salinity is to be managed in the Hunter Valley, its causes and behaviour must be understood. Although Hunter Valley hydrology, hydrogeology and hydrogeochemistry require further study, there is now enough information available to begin the development of both temporal and spatial models as valley management tools. Currently the Department of Water Resources is developing a model known as Integrated Water Quality and Quantity Model (IQQM). IQQM which includes a salinity module is essentially a surface water simulation model. It wll enable testing of alternate management and operation policies such as the salinity property rights trading scheme recently introduced by the EPA to manage salt release from coal mines and power stations. An overview is presented of the progress made to date on the salinity module for IQQM, and an outline is given of the geological and hydrogeochemical concepts that have been assembled to support the salinity module of IQQM. 17 refs., 3 figs., 1 tab.

The Subduction of an Exhumed and Serpentinized Magma-Poor Basement Beneath the Northern Lesser Antilles Reveals the Early Tectonic Fabric at Slow-Spreading Mid-Oceanic Ridges

Science.gov (United States)

Marcaillou, B.; Klingelhoefer, F.; Laurencin, M.; Biari, Y.; Graindorge, D.; Jean-Frederic, L.; Laigle, M.; Lallemand, S.

2017-12-01

Multichannel and wide-angle seismic data as well as heat-flow measurements (ANTITHESIS cruise, 2016) reveal a 200x200km patch of magma-poor oceanic basement in the trench and beneath the outer fore-arc offshore of Antigua to Saint Martin in the Northern Lesser Antilles. These data highlight an oceanic basement with the following features: 1/ Absence of any reflection at typical Moho depth and layer2/layer3 limit depths. 2/ High Velocity Vp at the top (>5.5 km/s), low velocity gradient with depth (serpentinized at the slow-spreading mid-Atlantic Ridge 80 Myr ago, is currently subducting beneath the Northern Lesser Antilles. During the exhumation, early extension triggers penetrative shear zones sub-parallel to the ridge and to the transform fault. Eventually, this early extension generates sliding along the so-called detachment fault, while the other proto-detachment abort. Approaching the trench, the plate bending reactivates these weak zones in normal faults and fluid pathways promoting deep serpentinisation and localizing tectonic deformation at the plate interface. These subducting fluid-rich mechanically weak mantle rocks rise questions about their relation to the faster slab deepening, the lower seismic activity and the pervasive tectonic partitioning in this margin segment.

perceptions and adaptations of beekeepers and honey hunters

African Journals Online (AJOL)

Prof. Adipala Ekwamu

honey sector (i.e. honey hunters) to climate change are, however, not adequately explored. The objective of .... The statistical software SPSS Version 16 was used for this purpose. ... content analysis is an effort of interpretation, that balances ... FORM. Discontinue. N o = 0 ; Yes = 1. ±. Creditavability. CRED. Discontinue. N.

Injury and Illness Among Deer Hunters

OpenAIRE

McRae, Shelagh M.

1989-01-01

General practice and out-patient emergency records for a five-year period were reviewed for injuries and illnesses that occurred during the week of deer rifle hunting on Manitoulin Island. Of 65 hunters who were identified, most had lacerations secondary to knife injuries. There were two deaths (one shooting and one in a motor vehicle accident), and 19 persons required hospitalization. More than half of these serious accidents occurred on the weekends immediately preceding or following the hu...

Project CHECO Southeast Asia Report. OV-1/AC-119 Hunter-Killer Team

Science.gov (United States)

1972-10-10

between Phan Rang, Phu Cat , and Danang in order to provide best coverage of the Vietnamese conflict. -- On 16 February 1970, three AC -ll9Ks and 70...SOUTHEAST ASIA D D DDiv AY/XDOSQA I OV-1/ AC -119 " i IWB I HUNTER-KILLER TEAM 19’.1’ CONTINUING REPORT CLASSIFIED Ey 7AFIDOOC DOWNGRADE TjU SECRET...xamination of C urrent, 0 per’tions I~ I fF!lr T I TII TIIII I OV=1/ AC -119 HUNTER-KILLER TEAMI 1 10 OCTOBER 1972 HQ PACAF Directorate of Operations

Ethical acceptability of recreational hunting - does the motive of the hunter matter?

DEFF Research Database (Denmark)

Gamborg, Christian; Jensen, Frank Søndergaard; Sandøe, Peter

2016-01-01

Recreational hunting can be a way of taking responsibility for acquiring one’s own meat. However, many recreational hunters focus instead on hunting as a hobby or sport. This distinction, between two rather different motives for hunting, is relevant to the activity’s moral justifiability. The pub......Recreational hunting can be a way of taking responsibility for acquiring one’s own meat. However, many recreational hunters focus instead on hunting as a hobby or sport. This distinction, between two rather different motives for hunting, is relevant to the activity’s moral justifiability...

Using obsidian transfer distances to explore social network maintenance in late Pleistocene hunter-gatherers.

Science.gov (United States)

Pearce, Eiluned; Moutsiou, Theodora

2014-12-01

Social behaviour is notoriously difficult to study archaeologically and it is unclear how large the networks of prehistoric humans were, or how they remained connected. Maintaining social cohesion was crucial for early humans because social networks facilitate cooperation and are imperative for survival and reproduction. Recent hunter-gatherer social organisation typically comprises a number of nested layers, ranging from the nuclear family through to the ~1500-strong ethnolinguistic tribe. Here we compare maximum obsidian transfer distances from the late Pleistocene with ethnographic data on the size of the geographic areas associated with each of these social grouping layers in recent hunter-gatherers. The closest match between the two is taken to indicate the maximum social layer within which contact could be sustained by Pleistocene hominins. Within both the (sub)tropical African and Subarctic biomes, the maximum obsidian transfer distances for Pleistocene modern humans (~200km and ~400km respectively) correspond to the geographic ranges of the outermost tribal layer in recent hunter-gatherers. This suggests that modern humans could potentially sustain the cohesion of their entire tribe at all latitudes, even though networks are more dispersed nearer the poles. Neanderthal obsidian transfer distances (300km) indicate that although Neanderthal home ranges are larger than those of low latitude hominins, Neanderthals travelled shorter distances than modern humans living at the same high latitudes. We argue that, like modern humans, Neanderthals could have maintained tribal cohesion, but that their tribes were substantially smaller than those of contemporary modern humans living in similar environments. The greater time taken to traverse the larger modern human tribal ranges may have limited the frequency of their face-to-face interactions and thus necessitated additional mechanisms to ensure network connectivity, such as the exchange of symbolic artefacts

Radium issues at Hunters Point Annex

International Nuclear Information System (INIS)

Dean, S.M.

1994-01-01

Radium was a common source of illumination used in numerous instruments and gauges for military equipment prior to 1970. As a result of its many military applications radium 226 is now a principle radionuclide of concern at military base closures sites throughout the United States. This is an overview of the site characterization strategy employed and a potential site remediation technology being considered at a radium contaminated landfill at Hunters Point Annex, a former U.S. Navy shipyard in San Francisco, California

Comparing Road-Kill Datasets from Hunters and Citizen Scientists in a Landscape Context

OpenAIRE

Florian Heigl; Carina R. Stretz; Wolfgang Steiner; Franz Suppan; Thomas Bauer; Gregor Laaha; Johann G. Zaller

2016-01-01

Road traffic has severe effects on animals, especially when road-kills are involved. In many countries, official road-kill data are provided by hunters or police; there are also road-kill observations reported by citizen scientists. The aim of the current study was to test whether road-kill reports by hunters stem from similar landscapes than those reported by citizen scientists. We analysed the surrounding landscapes of 712 road-kill reportings of European hares in the province of Lower Aust...

Undergraduate Planet Hunters: Tools and Results

Science.gov (United States)

Buzasi, Derek L.; Carboneau, Lindsey; Ferrell, Laura; Green, Gilbert; Kaiser, Maya; Kreke, Kira; Lundy, Samantha; Merritt, William; Passino, Matlin; Paxton, Harrison; Podaril, Alexandria; Stansfield, Alexis

2018-06-01

One student "Honors Experience" option at Florida Gulf Coast University is a research experience, and we have developed a "Planet Hunters" course to provide an astronomical research track that satisfies that requirement. Students spend the first semester learning astronomical background and exoplanet detection techniques, while the second semester is primarily devoted to planet searches in K2 data using student-oriented software tools developed specifically for the task. In this poster, we illustrate those tools and show results obtained by class participants during this years experience.

Crustal structure beneath the southern Korean Peninsula from local earthquakes

Science.gov (United States)

Kim, Kwang-Hee; Park, Jung-Ho; Park, Yongcheol; Hao, Tian-Yao; Kim, Han-Joon

2017-05-01

The 3-D subsurface structure beneath the southern Korean Peninsula is poorly known, even though such information could be key in verifying or rejecting several competing models of the tectonic evolution of East Asia. We constructed a 3-D velocity model of the upper crust beneath the southern Korean Peninsula using 19 935 P-wave arrivals from 747 earthquakes recorded by high-density local seismic networks. Results show significant lateral and vertical variations: velocity increases from northwest to southeast at shallow depths, and significant velocity variations are observed across the South Korea Tectonic Line between the Okcheon Fold Belt and the Youngnam Massif. Collision between the North and South China blocks during the Early Cretaceous might have caused extensive deformation and the observed negative velocity anomalies in the region. The results of the tomographic inversion, combined with the findings of previous studies of Bouguer and isostatic gravity anomalies, indicate the presence of high-density material in the upper and middle crust beneath the Gyeongsang Basin in the southeastern Korean Peninsula. Although our results partially support the indentation tectonic model, it is still premature to discard other tectonic evolution models because our study only covers the southern half of the peninsula.

Middle and Late Holocene hunter-gatherers in East Central Europe: changing paradigms of the ‘non-Neolithic’ way of life

Directory of Open Access Journals (Sweden)

Marek Nowak

2007-12-01

Full Text Available According to traditional views, the main reason for ‘demesolithisation’ in East Central Europe was the spread of the Neolithic oecumene, particularly from c. 4000 BC. Simultaneously, the disintegrated Late Mesolithic world gradually underwent typological unification, and finally reached the stage that is sometimes described as pre-Neolithic. However, we definitely have to bear in mind that as a matter of fact we deal only with the ‘history’ of archaeological artefacts that are treated as typical attributes of hunter-gatherers. The analyses of chronological, technological, settlement, economic, and social data referring to foragers of East Central Europe demonstrate that the quantitative decrease and changes of their archaeological attributes in the fifth, fourth, and third millennia were not connected with a profound reorientation of their spatial and ideological existence. It was rather a continuation of previous patterns, even though territories settled by farming societies were steadily growing in size. The final disappearance of Central European hunter-gatherers – but only in a strictly typological dimension – took place in the Late Neolithic and Early Bronze Age.

Did warfare among ancestral hunter-gatherers affect the evolution of human social behaviors?

Science.gov (United States)

Bowles, Samuel

2009-06-05

Since Darwin, intergroup hostilities have figured prominently in explanations of the evolution of human social behavior. Yet whether ancestral humans were largely "peaceful" or "warlike" remains controversial. I ask a more precise question: If more cooperative groups were more likely to prevail in conflicts with other groups, was the level of intergroup violence sufficient to influence the evolution of human social behavior? Using a model of the evolutionary impact of between-group competition and a new data set that combines archaeological evidence on causes of death during the Late Pleistocene and early Holocene with ethnographic and historical reports on hunter-gatherer populations, I find that the estimated level of mortality in intergroup conflicts would have had substantial effects, allowing the proliferation of group-beneficial behaviors that were quite costly to the individual altruist.

Targeting hunter distribution based on host resource selection and kill sites to manage disease risk

DEFF Research Database (Denmark)

Dugal, Cherie; van Beest, Floris; Vander Wal, Eric

2013-01-01

Endemic and emerging diseases are rarely uniform in their spatial distribution or prevalence among cohorts of wildlife. Spatial models that quantify risk-driven differences in resource selection and hunter mortality of animals at fine spatial scales can assist disease management by identifying high-risk...... areas and individuals. We used resource selection functions (RSFs) and selection ratios (SRs) to quantify sex- and age-specific resource selection patterns of collared (n = 67) and hunter-killed (n = 796) nonmigratory elk (Cervus canadensis manitobensis) during the hunting season between 2002 and 2012...... juvenile males and hunter-killed adult females. In instances where disease infects a metapopulation and eradication is infeasible, a principle goal of management is to limit the spread of disease among infected animals. We map high-risk areas that are regularly used by potentially infectious hosts...

Medicinal and ethnoveterinary remedies of hunters in Trinidad

Directory of Open Access Journals (Sweden)

Georges Karla

2001-11-01

Full Text Available Abstract Background Ethnomedicines are used by hunters for themselves and their hunting dogs in Trinidad. Plants are used for snakebites, scorpion stings, for injuries and mange of dogs and to facilitate hunting success. Results Plants used include Piper hispidum, Pithecelobium unguis-cati, Bauhinia excisa, Bauhinia cumanensis, Cecropia peltata, Aframomum melegueta, Aristolochia rugosa, Aristolochia trilobata, Jatropha curcas, Jatropha gossypifolia, Nicotiana tabacum, Vernonia scorpioides, Petiveria alliacea, Renealmia alpinia, Justicia secunda, Phyllanthus urinaria,Phyllanthus niruri,Momordica charantia, Xiphidium caeruleum, Ottonia ovata, Lepianthes peltata, Capsicum frutescens, Costus scaber, Dendropanax arboreus, Siparuma guianensis, Syngonium podophyllum, Monstera dubia, Solanum species, Eclipta prostrata, Spiranthes acaulis, Croton gossypifolius, Barleria lupulina, Cola nitida, Acrocomia ierensis (tentative ID. Conclusion Plant use is based on odour, and plant morphological characteristics and is embedded in a complex cultural context based on indigenous Amerindian beliefs. It is suggested that the medicinal plants exerted a physiological action on the hunter or his dog. Some of the plants mentioned contain chemicals that may explain the ethnomedicinal and ethnoveterinary use. For instance some of the plants influence the immune system or are effective against internal and external parasites. Plant baths may contribute to the health and well being of the hunting dogs.

Medicinal and ethnoveterinary remedies of hunters in Trinidad.

Science.gov (United States)

Lans, C; Harper, T; Georges, K; Bridgewater, E

2001-01-01

Ethnomedicines are used by hunters for themselves and their hunting dogs in Trinidad. Plants are used for snakebites, scorpion stings, for injuries and mange of dogs and to facilitate hunting success. Plants used include Piper hispidum, Pithecelobium unguis-cati, Bauhinia excisa, Bauhinia cumanensis, Cecropia peltata, Aframomum melegueta, Aristolochia rugosa, Aristolochia trilobata, Jatropha curcas, Jatropha gossypifolia, Nicotiana tabacum, Vernonia scorpioides, Petiveria alliacea, Renealmia alpinia, Justicia secunda, Phyllanthus urinaria,Phyllanthus niruri,Momordica charantia, Xiphidium caeruleum, Ottonia ovata, Lepianthes peltata, Capsicum frutescens, Costus scaber, Dendropanax arboreus, Siparuma guianensis, Syngonium podophyllum, Monstera dubia, Solanum species, Eclipta prostrata, Spiranthes acaulis, Croton gossypifolius, Barleria lupulina, Cola nitida, Acrocomia ierensis (tentative ID). Plant use is based on odour, and plant morphological characteristics and is embedded in a complex cultural context based on indigenous Amerindian beliefs. It is suggested that the medicinal plants exerted a physiological action on the hunter or his dog. Some of the plants mentioned contain chemicals that may explain the ethnomedicinal and ethnoveterinary use. For instance some of the plants influence the immune system or are effective against internal and external parasites. Plant baths may contribute to the health and well being of the hunting dogs.

Intergroup aggression in chimpanzees and war in nomadic hunter-gatherers: evaluating the chimpanzee model.

Science.gov (United States)

Wrangham, Richard W; Glowacki, Luke

2012-03-01

Chimpanzee and hunter-gatherer intergroup aggression differ in important ways, including humans having the ability to form peaceful relationships and alliances among groups. This paper nevertheless evaluates the hypothesis that intergroup aggression evolved according to the same functional principles in the two species-selection favoring a tendency to kill members of neighboring groups when killing could be carried out safely. According to this idea chimpanzees and humans are equally risk-averse when fighting. When self-sacrificial war practices are found in humans, therefore, they result from cultural systems of reward, punishment, and coercion rather than evolved adaptations to greater risk-taking. To test this "chimpanzee model," we review intergroup fighting in chimpanzees and nomadic hunter-gatherers living with other nomadic hunter-gatherers as neighbors. Whether humans have evolved specific psychological adaptations for war is unknown, but current evidence suggests that the chimpanzee model is an appropriate starting point for analyzing the biological and cultural evolution of warfare.

Estimating the mercury exposure dose in a population of migratory bird hunters in the St. Lawrence River region, Quebec, Canada

International Nuclear Information System (INIS)

Duchesne, J.-F.; Levesque, B.; Gauvin, Denis; Braune, Birgit; Gingras, Suzanne; Dewailly, E.

2004-01-01

St. Lawrence River hunters (Quebec, Canada) are exposed to the pollutants, especially mercury, that contaminate birds and fish. However, the health risks of this have remained unclear because of a lack of information about the hunters' duck, geese, and sportfish consumption habits. A nutritional survey was set up to characterize waterfowl and sportfish consumption in St. Lawrence River duck hunters and to estimate their daily exposure to mercury. During the winter of 2000, 512 hunters selected from the Canadian Wildlife Service database completed a self-administered questionnaire. Daily exposure to contaminants was measured using data from the Canadian Wildlife Service (waterfowl) and available data on St. Lawrence River sportfish. The annual average consumption was 7.5 meals of ducks and geese and 8.7 meals of sportfish. The daily exposure to mercury related to waterfowl consumption was below the Canadian tolerable daily intake (TDI) of 0.47 μg/kg body wt/day for all participants. The daily mercury intake associated with fish consumption was greater than the TDI in 2 duck hunters. The daily exposure to mercury was higher than the TDI in 4 participants when both waterfowl and fish consumption were combined. Our results suggest that fish consumption (especially freshwater fish) represents the main source of exposure to pollutants in duck hunters

Firewood, food and human niche construction: the potential role of Mesolithic hunter-gatherers in actively structuring Scotland's woodlands

Science.gov (United States)

Bishop, Rosie R.; Church, Mike J.; Rowley-Conwy, Peter A.

2015-01-01

Over the past few decades the potential role of Mesolithic hunter-gatherers in actively constructing their own niches, through the management of wild plants, has frequently been discussed. It is probable that Mesolithic hunter-gatherers systematically exploited specific woodland resources for food and fuel and influenced the 'natural' abundance or distribution of particular species within Mesolithic environments. Though there has been considerable discussion of the pollen evidence for potential small-scale human-woodland manipulation in Mesolithic Scotland, the archaeobotanical evidence for anthropogenic firewood and food selection has not been discussed in this context. This paper assesses the evidence for the active role of Mesolithic hunter-gatherer communities in systematically exploiting and managing woodlands for food and fuel in Scotland. While taphonomic factors may have impacted on the frequency of specific species in archaeobotanical assemblages, it is suggested that hunter-gatherers in Mesolithic Scotland were systematically using woodland plants, and in particular hazel and oak, for food and fuel. It is argued that the pollen evidence for woodland management is equivocal, but hints at the role of hunter-gatherers in shaping the structure of their environments, through the maintenance or creation of woodland clearings for settlement or as part of vegetation management strategies. It is proposed that Mesolithic hunter-gatherers may have actively contributed to niche construction and that the systematic use of hazel and oak as a fuel may reflect the deliberate pruning of hazel trees to increase nut-yields and the inadvertent - or perhaps deliberate - coppicing of hazel and oak during greenwood collection.

SHRIMP zircon dating and LA-ICPMS Hf analysis of early Precambrian rocks from drill holes into the basement beneath the Central Hebei Basin, North China Craton

Directory of Open Access Journals (Sweden)

Yusheng Wan

2014-07-01

Full Text Available The Central Hebei Basin (CHB is one of the largest sedimentary basins in the North China Craton, extending in a northeast–southwest direction with an area of >350 km2. We carried out SHRIMP zircon dating, Hf-in-zircon isotopic analysis and a whole-rock geochemical study on igneous and metasedimentary rocks recovered from drill holes that penetrated into the basement of the CHB. Two samples of gneissic granodiorite (XG1-1 and gneissic quartz diorite (J48-1 have magmatic ages of 2500 and 2496 Ma, respectively. Their zircons also record metamorphic ages of 2.41–2.51 and ∼2.5 Ga, respectively. Compared with the gneissic granodiorite, the gneissic quartz diorite has higher ΣREE contents and lower Eu/Eu* and (La/Ybn values. Two metasedimentary samples (MG1, H5 mainly contain ∼2.5 Ga detrital zircons as well as late Paleoproterozoic metamorphic grains. The zircons of different origins have εHf (2.5 Ga values and Hf crustal model ages ranging from 0 to 5 and 2.7 to 2.9 Ga, respectively. Therefore, ∼2.5 Ga magmatic and Paleoproterozoic metasedimentary rocks and late Neoarchean to early Paleoproterozoic and late Paleoproterozoic tectono-thermal events have been identified in the basement beneath the CHB. Based on regional comparisons, we conclude that the early Precambrian basement beneath the CHB is part of the North China Craton.

Fundación Book Hunters: Atrévete a experimentar con la lectura

OpenAIRE

Cruz Mejía, Fernanda

2017-01-01

La fundación Book Hunters es una organización sin ánimo de lucro que busca fortalecer la relación de la lectura en los niños desde temprana edad, involucrando a la comunidad y promoviendo el entendimiento del entorno que rodea hoy en día la infancia. El equipo considera que, para lograr los objetivos es necesario transformar el significado ha perseguido a la lectura durante años, es decir, para Book Hunters leer va más allá de tomar un libro e involucrarse en la historia, en cambio, el si...

Radioactive caesium in hunters and their families

Energy Technology Data Exchange (ETDEWEB)

Aagren, G; Bergman, R [Natonal Defence Research Establishment, Umeaa (Sweden); Drottz-Sjoeberg, B M [Center for Risk Research, Stockholm (Sweden); Enander, A [National Defence Research Establishment, Karlstad (Sweden); Johansson, K J [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden)

1995-12-01

We have measured the whole-body content of radiocesium in men and women in households, where at least one member is a hunter. Hunter families live to a great extent on forest products, such as mushrooms, berries and meat from game. Measurements were performed in two areas in northern Sweden and in three areas in the middle part of Sweden with deposition levels between 7 to 80 kBq/m{sup 2}. The average whole body content of {sup 137}Cs varied between 0.3 to 1.9 kBq for women and 0.6 to 4.7 kBq for men, depending on the deposition level. Each individual in the measured group was also asked to fill in questionnaire and a food diary to provide complementary information of, e.g., food intake and other life conditions. The single dietary factor most clearly related to whole-body content in these groups is the intake of meat from moose. The best regression model with variables from the questionnaire explained 60% of the variance in the whole-body content of {sup 137}Cs in the measurement group. Some of the variables in this model were deposition level, sex, rate of intake and estimated consumption of moose meat and estimated amount of bilberries in the fridge. 6 refs, 5 figs, 14 tabs.

Radioactive caesium in hunters and their families

International Nuclear Information System (INIS)

Aagren, G.; Bergman, R.; Drottz-Sjoeberg, B.M.; Enander, A.; Johansson, K.J.

1995-12-01

We have measured the whole-body content of radiocesium in men and women in households, where at least one member is a hunter. Hunter families live to a great extent on forest products, such as mushrooms, berries and meat from game. Measurements were performed in two areas in northern Sweden and in three areas in the middle part of Sweden with deposition levels between 7 to 80 kBq/m 2 . The average whole body content of 137 Cs varied between 0.3 to 1.9 kBq for women and 0.6 to 4.7 kBq for men, depending on the deposition level. Each individual in the measured group was also asked to fill in questionnaire and a food diary to provide complementary information of, e.g., food intake and other life conditions. The single dietary factor most clearly related to whole-body content in these groups is the intake of meat from moose. The best regression model with variables from the questionnaire explained 60% of the variance in the whole-body content of 137 Cs in the measurement group. Some of the variables in this model were deposition level, sex, rate of intake and estimated consumption of moose meat and estimated amount of bilberries in the fridge. 6 refs, 5 figs, 14 tabs

Reducing Lead on the Landscape: Anticipating Hunter Behavior in Absence of a Free Nonlead Ammunition Program.

Directory of Open Access Journals (Sweden)

Loren Chase

Full Text Available Lead is a neurotoxin that has been documented to affect many forms of wildlife, and has been identified as a limiting factor in a population of California Condors in Northern Arizona. The Arizona Game and Fish Department provides vouchers for free nonlead ammunition to hunters selected to hunt within the distribution of California Condors, with the intention of having fewer lead-laden offal piles available to California Condors. Although wildlife agencies may reasonably assume voucher programs motivate hunters into choosing nonlead ammunition, the lead reduction efforts attributable to the voucher program has not been empirically quantified. Our intention was to compare a control group of hunters to a treatment group of hunters within California Condor occupied areas. Both groups received educational materials regarding the deleterious effects of lead, but the treatment group also received a voucher for a free initial box of ammunition. About half of the control group used nonlead ammunition, compared to about three-fourths of the treatment group. Prominent barriers to adoption of nonlead ammunition included a general difficulty of obtaining it, obtaining it in the desired caliber, and its costliness. Frequently mentioned motivations for using nonlead was the exhortation to use it by the Department, and the desire to aid California Condor recovery by hunters. The disparate compliance rates found herein confirm and quantify the success of nonlead ammunition voucher programs, but underscore the importance of working to increase the supply of nonlead ammunition with the end of facilitating its procurement and reducing its cost.

Diagnosis of Hunter's syndrome carriers; radioactive sulphate incorporation into fibroblasts in the presence of fructose 1-phosphate

International Nuclear Information System (INIS)

Toennesen, T.; Lykkelund, C.; Guettler, F.

1982-01-01

Mutual correction of co-cultivated fibroblasts from patients with Hunter's and Hurler's syndrome could be inhibited by either fructose 1-phosphate or mannose 6-phosphate. In the presence of fructose 1-phosphate a 50% mixture of fibroblasts from a patient with Hunter's syndrome and a normal homozygous individual showed an increased 35 S-sulphate incorporation into acid mucopolysaccharides. When fibroblast cultures from one obligate and two possible carriers of Hunter's syndrome were tested for 35 S-sulphate incorporation, the cultures showed either twice the normal 35 S-sulphate incorporation into acid mucopolysaccharides in the presence of fructose 1-phosphate or an abnormally high incorporation in the presence as well as in the absence of the sugar phosphate. (orig.)

Hunters syndrom og hørenedsaettelse

DEFF Research Database (Denmark)

Kiaer, Eva Kirkegaard; Møller, Troels Reinholdt; Wetke, Randi

2010-01-01

A 30 month-old boy with delayed language development was referred to the Department of Audiology in Aarhus. At the time of referral he had had 19 cases of acute otitis media and had been tubulated four times. Furthermore, the boy had not developed according to age in several respects: his motor...... functions and language were delayed, and he made audible respiratory sounds and was obviously nasally congested. The boy was referred for further investigations at the Department of Paediatrics. The tests showed that the boy suffered from Hunter Syndrome (MPSII) and he underwent relevant treatment....

Contrasts in livelihoods and protein intake between commercial and subsistence bushmeat hunters in two villages on Bioko Island, Equatorial Guinea.

Science.gov (United States)

Vega, María Grande; Carpinetti, Bruno; Duarte, Jesús; Fa, John E

2013-06-01

Across West and Central Africa, wildlife provides a source of food and income. We investigated the relation between bushmeat hunting and household wealth and protein consumption in 2 rural communities in Bioko Island, Equatorial Guinea. One village was dedicated to commercial hunting, the other trapped game primarily for food. We tested whether commercial-hunter households were nutritionally advantaged over subsistence-hunter households due to their higher income from the bushmeat trade and greater access to wild-animal protein. We conducted bushmeat-offtake surveys in both villages (captures by hunters and carcasses arriving to each village). Mammals (including threatened primates: black colobus [Colobus satanas], Preussi's guenon [Allochrocebus preussi], and russet-eared guenon [Cercopithecus erythrotis]), birds, and reptiles were hunted. The blue duiker (Philantomba monticola), giant pouched rat (Cricetomys emini), and brush-tailed porcupine (Atherurus africanus) contributed almost all the animal biomass hunted, consumed, or sold in both villages. Monkeys and Ogilbyi's duikers (Cephalophus ogilbyi) were hunted only by commercial hunters. Commercial hunters generated a mean of US$2000/year from bushmeat sales. Households with commercial hunters were on average wealthier, generated more income, spent more money on nonessential goods, and bought more products they did not grow. By contrast, households with subsistence hunters spent less on market items, spent more on essential products, and grew more of their own food. Despite these differences, average consumption of vegetable protein and domestic meat and bushmeat protein did not differ between villages. Our results highlight the importance of understanding the socioeconomic and nutritional context of commercial and subsistence bushmeat hunting to correctly interpret ways of reducing their effects on threatened species and to enable the sustainable offtake of more productive taxa. © 2013 Society for Conservation

Project CHECO Southeast Asia Report. OV-1/AC-119 Hunter-Killer Team

National Research Council Canada - National Science Library

Sexton, Richard R; Hodgson, William M

1972-01-01

Hunter-Killer operations were but a logical extension of the resourceful thinking behind the development of gunships as a solution to some of the tactical problems of the unique war in Southeast Asia...

Linking Hunter Knowledge with Forest Change to Understand Changing Deer Harvest Opportunities in Intensively Logged Landscapes

Directory of Open Access Journals (Sweden)

Todd J. Brinkman

2009-06-01

Full Text Available The effects of landscape changes caused by intensive logging on the availability of wild game are important when the harvest of wild game is a critical cultural practice, food source, and recreational activity. We assessed the influence of extensive industrial logging on the availability of wild game by drawing on local knowledge and ecological science to evaluate the relationship between forest change and opportunities to harvest Sitka black-tailed deer (Odocoileus hemionus sitkensis on Prince of Wales Island, Alaska. We used data collected through interviews with local deer hunters and GIS analysis of land cover to determine relationships among landscape change, hunter access, and habitat for deer hunting over the last 50 yr. We then used these relationships to predict how harvest opportunities may change in the future. Intensive logging from 1950 into the 1990s provided better access to deer and habitat that facilitated deer hunting. However, successional changes in intensively logged forests in combination with a decline in current logging activity have reduced access to deer and increased undesirable habitat for deer hunting. In this new landscape, harvest opportunities in previously logged landscapes have declined, and hunters identify second-growth forest as one of the least popular habitats for hunting. Given the current state of the logging industry in Alaska, it is unlikely that the logging of the remaining old-growth forests or intensive management of second-growth forests will cause hunter opportunities to rebound to historic levels. Instead, hunter opportunities may continue to decline for at least another human generation, even if the long-term impacts of logging activity and deer harvest on deer numbers are minimal. Adapting hunting strategies to focus on naturally open habitats such as alpine and muskeg that are less influenced by external market forces may require considerably more hunting effort but provide the best option for

Sacrificing Steve: How I Killed the Crocodile Hunter

Directory of Open Access Journals (Sweden)

Luke Carman

2010-09-01

Full Text Available Bob Hodge and Vijay Mishra argue that the complex issues of illegitimacy at the core of Australian identity are repressed through a continual process of cyclical silencing, where traces of a shameful past are exorcised by a focus on images of a mythologised ‘legend’, embodied in characters such as 'The Man from Snowy River'. This article explores such a 'schizophrenic' cycle in relation to the life, death and resurrection of Steve 'Crocodile Hunter' Irwin.

Hide Tanning and Its Use in Taiga: The Case of the Orochen-Evenki Reindeer Herders and Hunters of Zabaikalye (East Siberia)

OpenAIRE

Donatas Brandišauskas

2010-01-01

This article documents the way in which the Orochen-Evenki hunters and herders in northern part of Zabaikalye tan hides and produce gear in the post-Soviet era. Here, I wish to present the argument that it is difficult to understand the reviving of hide tanning in remote villages and the taiga without understanding how hunters and herders in this region adapt to the unstable post-Soviet environment. I suggest that hunters and herders aim to maintain their autonomy from goods and resources imp...

Preliminary assessment of channel stability and bed-material transport along Hunter Creek, southwestern Oregon

Science.gov (United States)

Jones, Krista L.; Wallick, J. Rose; O'Connor, Jim E.; Keith, Mackenzie K.; Mangano, Joseph F.; Risley, John C.

2011-01-01

This preliminary assessment of (1) bed-material transport in the Hunter Creek basin, (2) historical changes in channel condition, and (3) supplementary data needed to inform permitting decisions regarding instream gravel extraction revealed the following: Along the lower 12.4 km (kilometers) of Hunter Creek from its confluence with the Little South Fork Hunter Creek to its mouth, the river has confined and unconfined segments and is predominately alluvial in its lowermost 11 km. This 12.4-km stretch of river can be divided into two geomorphically distinct study reaches based primarily on valley physiography. In the Upper Study Reach (river kilometer [RKM] 12.4-6), the active channel comprises a mixed bed of bedrock, boulders, and smaller grains. The stream is confined in the upper 1.4 km of the reach by a bedrock canyon and in the lower 2.4 km by its valley. In the Lower Study Reach (RKM 6-0), where the area of gravel bars historically was largest, the stream flows over bed material that is predominately alluvial sediments. The channel alternates between confined and unconfined segments. The primary human activities that likely have affected bed-material transport and the extent and area of gravel bars are (1) historical and ongoing aggregate extraction from gravel bars in the study area and (2) timber harvest and associated road construction throughout the basin. These anthropogenic activities likely have varying effects on sediment transport and deposition throughout the study area and over time. Although assessing the relative effects of these anthropogenic activities on sediment dynamics would be challenging, the Hunter Creek basin may serve as a case study for such an assessment because it is mostly free of other alterations to hydrologic and geomorphic processes such as flow regulation, dredging, and other navigation improvements that are common in many Oregon coastal basins. Several datasets are available that may support a more detailed physical assessment

HiggsHunters - a citizen science project for ATLAS

CERN Document Server

Haas, Andrew; The ATLAS collaboration

2016-01-01

Since the launch of HiggsHunters.org in November 2014, citizen science volunteers have classified more than a million points of interest in images from the ATLAS experiment at the LHC. Volunteers have been looking for displaced vertices and unusual features in images recorded during LHC Run-1. We discuss the design of the project, its impact on the public, and the surprising results of how the human volunteers performed relative to the computer algorithms in identifying displaced secondary vertices.

JEFX 10 demonstration of Cooperative Hunter Killer UAS and upstream data fusion

Science.gov (United States)

Funk, Brian K.; Castelli, Jonathan C.; Watkins, Adam S.; McCubbin, Christopher B.; Marshall, Steven J.; Barton, Jeffrey D.; Newman, Andrew J.; Peterson, Cammy K.; DeSena, Jonathan T.; Dutrow, Daniel A.; Rodriguez, Pedro A.

2011-05-01

The Johns Hopkins University Applied Physics Laboratory deployed and demonstrated a prototype Cooperative Hunter Killer (CHK) Unmanned Aerial System (UAS) capability and a prototype Upstream Data Fusion (UDF) capability as participants in the Joint Expeditionary Force Experiment 2010 in April 2010. The CHK capability was deployed at the Nevada Test and Training Range to prosecute a convoy protection operational thread. It used mission-level autonomy (MLA) software applied to a networked swarm of three Raven hunter UAS and a Procerus Miracle surrogate killer UAS, all equipped with full motion video (FMV). The MLA software provides the capability for the hunter-killer swarm to autonomously search an area or road network, divide the search area, deconflict flight paths, and maintain line of sight communications with mobile ground stations. It also provides an interface for an operator to designate a threat and initiate automatic engagement of the target by the killer UAS. The UDF prototype was deployed at the Maritime Operations Center at Commander Second Fleet, Naval Station Norfolk to provide intelligence analysts and the ISR commander with a common fused track picture from the available FMV sources. It consisted of a video exploitation component that automatically detected moving objects, a multiple hypothesis tracker that fused all of the detection data to produce a common track picture, and a display and user interface component that visualized the common track picture along with appropriate geospatial information such as maps and terrain as well as target coordinates and the source video.

Co-residence patterns in hunter-gatherer societies show unique human social structure.

Science.gov (United States)

Hill, Kim R; Walker, Robert S; Bozicević, Miran; Eder, James; Headland, Thomas; Hewlett, Barry; Hurtado, A Magdalena; Marlowe, Frank; Wiessner, Polly; Wood, Brian

2011-03-11

Contemporary humans exhibit spectacular biological success derived from cumulative culture and cooperation. The origins of these traits may be related to our ancestral group structure. Because humans lived as foragers for 95% of our species' history, we analyzed co-residence patterns among 32 present-day foraging societies (total n = 5067 individuals, mean experienced band size = 28.2 adults). We found that hunter-gatherers display a unique social structure where (i) either sex may disperse or remain in their natal group, (ii) adult brothers and sisters often co-reside, and (iii) most individuals in residential groups are genetically unrelated. These patterns produce large interaction networks of unrelated adults and suggest that inclusive fitness cannot explain extensive cooperation in hunter-gatherer bands. However, large social networks may help to explain why humans evolved capacities for social learning that resulted in cumulative culture.

AllerHunter: a SVM-pairwise system for assessment of allergenicity and allergic cross-reactivity in proteins.

Directory of Open Access Journals (Sweden)

Hon Cheng Muh

Full Text Available Allergy is a major health problem in industrialized countries. The number of transgenic food crops is growing rapidly creating the need for allergenicity assessment before they are introduced into human food chain. While existing bioinformatic methods have achieved good accuracies for highly conserved sequences, the discrimination of allergens and non-allergens from allergen-like non-allergen sequences remains difficult. We describe AllerHunter, a web-based computational system for the assessment of potential allergenicity and allergic cross-reactivity in proteins. It combines an iterative pairwise sequence similarity encoding scheme with SVM as the discriminating engine. The pairwise vectorization framework allows the system to model essential features in allergens that are involved in cross-reactivity, but not limited to distinct sets of physicochemical properties. The system was rigorously trained and tested using 1,356 known allergen and 13,449 putative non-allergen sequences. Extensive testing was performed for validation of the prediction models. The system is effective for distinguishing allergens and non-allergens from allergen-like non-allergen sequences. Testing results showed that AllerHunter, with a sensitivity of 83.4% and specificity of 96.4% (accuracy = 95.3%, area under the receiver operating characteristic curve AROC = 0.928+/-0.004 and Matthew's correlation coefficient MCC = 0.738, performs significantly better than a number of existing methods using an independent dataset of 1443 protein sequences. AllerHunter is available at (http://tiger.dbs.nus.edu.sg/AllerHunter.

Seasonal variation in Eurasian Wigeon Anas penelope sex and age ratios from hunter-based surveys

DEFF Research Database (Denmark)

Clausen, Kevin Kuhlmann; Dalby, Lars; Sunde, Peter

2013-01-01

dominated by adult males, and juvenile proportions were highest in November and significantly lower before and after this peak. Nationwide field assessments undertaken in January 2012 showed no significant differences from sex and age ratios in the wing survey data from that particular hunting season (2011...... schemes. This study found consistent seasonal variation in Eurasian Wigeon Anas penelope sex and age ratios among Danish hunter-based wing surveys, and describes how accounting for this variation might explain reported discrepancies between this and other monitoring methods. Early season flocks were....../2012), indicating that this survey is a good predictor of Wigeon demography. These results highlight the need to account for consistent temporal variation in such demographic time series when using the results to model population parameters....

Early Holocene environmental change and the impact of Mesolithic man in the Tungelroysche Beek Valley, N-Limburg

NARCIS (Netherlands)

Woelders, L.; Kort, J.W. de; Hoek, W.Z.

2012-01-01

An archaeological excavation in the Tungelroysche Beek Valley revealed an Early Mesolithic site with the unique discovery of the remains of two red deer specimens (Cervus elaphus), likely the victims of Early Mesolithic hunter-gatherers. A core taken by the Rijksdienst voor het Cultureel Erfgoed

Energy expenditure and activity among Hadza hunter-gatherers.

Science.gov (United States)

Pontzer, Herman; Raichlen, David A; Wood, Brian M; Emery Thompson, Melissa; Racette, Susan B; Mabulla, Audax Z P; Marlowe, Frank W

2015-01-01

Studies of total energy expenditure, (TEE; kcal/day) among traditional populations have challenged current models relating habitual physical activity to daily energy requirements. Here, we examine the relationship between physical activity and TEE among traditional Hadza hunter-gatherers living in northern Tanzania. Hadza adults were studied at two camps, with minimal intervention so as to monitor energy expenditure and activity during normal daily life. We measured daily walking distance and walking speed using wearable GPS units for 41 adults. For a subset of 30 adults, we measured TEE using doubly labeled water, three indices of work load (foraging return rate, maternal status, and number of dependent children), and urinary biomarkers of metabolic activity and stress (8-hydroxydeoxyguanosine, cortisol, and testosterone). Fat-free mass was the single strongest predictor of TEE among Hadza adults (r(2)  = 0.66, P < 0.001). Hadza men used greater daily walking distances and faster walking speeds compared with that of Hadza women, but neither sex nor any measure of physical activity or work load were correlated with TEE in analyses controlling for fat-free mass. Compared with developed, industrial populations, Hadza adults had similar TEE but elevated levels of metabolic stress as measured by 8-hydroxydeoxyguanosine. Our results indicate that daily physical activity may not predict TEE within traditional hunter-gatherer populations like the Hadza. Instead, adults with high levels of habitual physical activity may adapt by reducing energy allocation to other physiological activity. © 2015 Wiley Periodicals, Inc.

Mortality, fertility, and the OY ratio in a model hunter-gatherer system.

Science.gov (United States)

White, Andrew A

2014-06-01

An agent-based model (ABM) is used to explore how the ratio of old to young adults (the OY ratio) in a sample of dead individuals is related to aspects of mortality, fertility, and longevity experienced by the living population from which the sample was drawn. The ABM features representations of rules, behaviors, and constraints that affect person- and household-level decisions about marriage, reproduction, and infant mortality in hunter-gatherer systems. The demographic characteristics of the larger model system emerge through human-level interactions playing out in the context of "global" parameters that can be adjusted to produce a range of mortality and fertility conditions. Model data show a relationship between the OY ratios of living populations (the living OY ratio) and assemblages of dead individuals drawn from those populations (the dead OY ratio) that is consistent with that from empirically known ethnographic hunter-gatherer cases. The dead OY ratio is clearly related to the mean ages, mean adult mortality rates, and mean total fertility rates experienced by living populations in the model. Sample size exerts a strong effect on the accuracy with which the calculated dead OY ratio reflects the actual dead OY ratio of the complete assemblage. These results demonstrate that the dead OY ratio is a potentially useful metric for paleodemographic analysis of changes in mortality and mean age, and suggest that, in general, hunter-gatherer populations with higher mortality, higher fertility, and lower mean ages are characterized by lower dead OY ratios. Copyright © 2014 Wiley Periodicals, Inc.

P-wave velocity structure beneath the northern Antarctic Peninsula

Science.gov (United States)

Park, Y.; Kim, K.; Jin, Y.

2010-12-01

We have imaged tomographically the tree-dimensional velocity structure of the upper mantle beneath the northern Antarctic Peninsula using teleseismic P waves. The data came from the seven land stations of the Seismic Experiment in Patagonia and Antarctica (SEPA) campaigned during 1997-1999, a permanent IRIS/GSN station (PMSA), and 3 seismic stations installed at scientific bases, Esperanza (ESPZ), Jubany (JUBA), and King Sejong (KSJ), in South Shetland Islands. All of the seismic stations are located in coast area, and the signal to noise ratios (SNR) are very low. The P-wave model was inverted from 95 earthquakes resulting in 347 ray paths with P- and PKP-wave arrivals. The inverted model shows a strong low velocity anmaly beneath the Bransfield Strait, and a fast anomaly beneath the South Shetland Islands. The low velocity anomaly beneath the Bransfield might be due to a back arc extension, and the fast velocity anomaly beneath the South Shetland Islands could indicates the cold subducted slab.

Fairy tales? Marion Jones, C.J. Hunter and the framing of doping in American newspapers

DEFF Research Database (Denmark)

Pfister, Gertrud Ursula; Gems, Gerald

2015-01-01

This article deals with the images, metaphors and narratives in the media coverage of doping in the United States. It presents a case study with a focus on Marion Jones, the most celebrated track athlete of the turn of the millennium, and her husband, C.J. Hunter, a shot put world champion...... under suspicion. At the same time, the 2000 Olympics can be considered a watershed in American anti-doping policy. The media portrayed Jones and Hunter as the Beauty and the Beast or Svengali and his victim, using a famous fairy tale and a well-known novel to capture attention, label the protagonists...

Game meat consumption by hunters and their relatives: A probabilistic approach.

Science.gov (United States)

Sevillano Morales, Jesus; Moreno-Ortega, Alicia; Amaro Lopez, Manual Angel; Arenas Casas, Antonio; Cámara-Martos, Fernando; Moreno-Rojas, Rafael

2018-06-18

This study aimed to estimate the consumption of meat and products derived from hunting by the consumer population and, specifically, by hunters and their relatives. For this purpose, a survey was conducted on the frequency of consuming meat from the four most representative game species in Spain, two of big game, wild boar (Sus scrofa) and red deer (Cervus elaphus) and two of small game, rabbit (Oryctolagus cunulucus) and red partridge (Alectoris rufa), as well as of processed meat products (salami-type sausage) made from those big game species. The survey was carried out on 337 habitual consumers of these types of products (hunters and their relatives). The total mean game meat consumption, per capita in this population group, is 6.87 kg/person/year of meat and 8.57 kg/person/year if the processed meat products are also considered. Consumption of rabbit, red partridge, red deer and wild boar, individually, was 1.85, 0.82, 2.28 and 1.92 kg/person/year, respectively. It was observed that hunters generally registered a larger intake of game meat, this being statistically significant in the case of rabbit meat consumption. Using probabilistic methods, the meat consumption frequency distributions for each hunting species studied were estimated, as well as the products made from big game species and the total consumption both of meat by itself and that including the products made from it. The consumption frequency distributions were adjusted to exponential ones, verified by the test suitable for it according to Akaike Information Criterion, Bayesian Information Criterion, the Chi-Squared and Kolmogorov-Smirnov statistics. In addition, the consumption percentiles of the different distributions were obtained. The latter could be a good tool when making nutrition or contaminant studies since they permit the assessment of exposure to the compound in question.

Hide Tanning and Its Use in Taiga: The Case of the Orochen-Evenki Reindeer Herders and Hunters of Zabaikalye (East Siberia

Directory of Open Access Journals (Sweden)

Donatas Brandišauskas

2011-05-01

Full Text Available This article documents the way in which the Orochen-Evenki hunters and herders in northern part of Zabaikalye tan hides and produce gear in the post-Soviet era. Here, I wish to present the argument that it is difficult to understand the reviving of hide tanning in remote villages and the taiga without understanding how hunters and herders in this region adapt to the unstable post-Soviet environment. I suggest that hunters and herders aim to maintain their autonomy from goods and resources imported from cities, and, in spending little effort connecting with state powers in this way, securing their lives from socio-economic constraints.

Hide Tanning and Its Use in Taiga: The Case of the Orochen-Evenki Reindeer Herders and Hunters of Zabaikalye (East Siberia

Directory of Open Access Journals (Sweden)

Donatas Brandišauskas

2010-12-01

Full Text Available This article documents the way in which the Orochen-Evenki hunters and herders in northern part of Zabaikalye tan hides and produce gear in the post-Soviet era. Here, I wish to present the argument that it is difficult to understand the reviving of hide tanning in remote villages and the taiga without understanding how hunters and herders in this region adapt to the unstable post-Soviet environment. I suggest that hunters and herders aim to maintain their autonomy from goods and resources imported from cities, and, in spending little effort connecting with state powers in this way, securing their lives from socio-economic constraints.

Effect of Piper chaba Hunter, Piper sarmentosum Roxb. and Piper interruptum Opiz. on natural killer cell activity and lymphocyte proliferation.

Science.gov (United States)

Panthong, Sumalee; Itharat, Arunporn

2014-08-01

Immune system is the most important system ofhuman body. Thaifolk doctors have used some medicinal plants as an adaptogenic drug or immunomodulatory agent. Piper chaba Hunter, Piper sarmentosum Roxb. and Piper interruptum Opiz. are used by folk doctors to activate immune response in cancer patients. To investigate the effect on natural killer cell activity and on lymphocyte proliferation activity of water extract of P chaba Hunter P. sarmentosum Roxb. and P interruptum Opiz. MATERIAL ANDMETHOD: Plant materials were extracted by decoction method. All extracts were testedfor an immunomodulatory effect using PBMCs from twelve healthy donors by chromium release assay. Lymphocyte proliferation was also determined by 3H-thymidine uptake assay. The degree of activation was expressed as the stimulation index. The water extract of P chaba Hunter significantly increased lymphocyte proliferation at concentrations ofl ng/ml, 10 ng/ml, 1 μg/ml, 5 μg/ml, 10 μg/ml and 100 μg/ml. P sarmentosum Roxb., and P interruptum Opiz. extracts at those concentrations significantly stimulated lymphocyteproliferation. P sarmentosum Roxb. extractsignificantly increased natural killer (NK) cell activity at a concentration of 100 μg/ml but P chaba Hunter and P interruptum Opiz. extracts did not significantly stimulate natural killer cell activity. P chaba Hunter, P interruptum Opiz. andP sarmentosum Roxb. have an immunomodulatory effect especially for P sarmentosum Roxb. extract which can activate both lymphocyte proliferation and NK cell activity.

Learning from the mistakes of others: How female elk (Cervus elaphus) adjust behaviour with age to avoid hunters.

Science.gov (United States)

Thurfjell, Henrik; Ciuti, Simone; Boyce, Mark S

2017-01-01

In animal behaviour, there is a dichotomy between innate behaviours (e.g., temperament or personality traits) versus those behaviours shaped by learning. Innate personality traits are supposedly less evident in animals when confounded by learning acquired with experience through time. Learning might play a key role in the development and adoption of successful anti-predator strategies, and the related adaptation has the potential to make animals that are more experienced less vulnerable to predation. We carried out a study in a system involving a large herbivorous mammal, female elk, Cervus elaphus, and their primary predator, i.e., human hunters. Using fine-scale satellite telemetry relocations, we tested whether differences in behaviour depending on age were due solely to selection pressure imposed by human hunters, meaning that females that were more cautious were more likely to survive and become older. Or whether learning also was involved, meaning that females adjusted their behaviour as they aged. Our results indicated that both human selection and learning contributed to the adoption of more cautious behavioural strategies in older females. Whereas human selection of behavioural traits has been shown in our previous research, we here provide evidence of additive learning processes being responsible for shaping the behaviour of individuals in this population. Female elk are indeed almost invulnerable to human hunters when older than 9-10 y.o., confirming that experience contributes to their survival. Female elk monitored in our study showed individually changing behaviours and clear adaptation as they aged, such as reduced movement rates (decreased likelihood of encountering human hunters), and increased use of secure areas (forest and steeper terrain), especially when close to roads. We also found that elk adjusted behaviours depending on the type of threat (bow and arrow vs. rifle hunters). This fine-tuning by elk to avoid hunters, rather than just

Hunter disease eClinic: interactive, computer-assisted, problem-based approach to independent learning about a rare genetic disease

Directory of Open Access Journals (Sweden)

Moldovan Laura

2010-10-01

Full Text Available Abstract Background Computer-based teaching (CBT is a well-known educational device, but it has never been applied systematically to the teaching of a complex, rare, genetic disease, such as Hunter disease (MPS II. Aim To develop interactive teaching software functioning as a virtual clinic for the management of MPS II. Implementation and Results The Hunter disease eClinic, a self-training, user-friendly educational software program, available at the Lysosomal Storage Research Group (http://www.lysosomalstorageresearch.ca, was developed using the Adobe Flash multimedia platform. It was designed to function both to provide a realistic, interactive virtual clinic and instantaneous access to supporting literature on Hunter disease. The Hunter disease eClinic consists of an eBook and an eClinic. The eClinic is the interactive virtual clinic component of the software. Within an environment resembling a real clinic, the trainee is instructed to perform a medical history, to examine the patient, and to order appropriate investigation. The program provides clinical data derived from the management of actual patients with Hunter disease. The eBook provides instantaneous, electronic access to a vast collection of reference information to provide detailed background clinical and basic science, including relevant biochemistry, physiology, and genetics. In the eClinic, the trainee is presented with quizzes designed to provide immediate feedback on both trainee effectiveness and efficiency. User feedback on the merits of the program was collected at several seminars and formal clinical rounds at several medical centres, primarily in Canada. In addition, online usage statistics were documented for a 2-year period. Feedback was consistently positive and confirmed the practical benefit of the program. The online English-language version is accessed daily by users from all over the world; a Japanese translation of the program is also available. Conclusions The

Hunter disease eClinic: interactive, computer-assisted, problem-based approach to independent learning about a rare genetic disease.

Science.gov (United States)

Al-Jasmi, Fatma; Moldovan, Laura; Clarke, Joe T R

2010-10-25

Computer-based teaching (CBT) is a well-known educational device, but it has never been applied systematically to the teaching of a complex, rare, genetic disease, such as Hunter disease (MPS II). To develop interactive teaching software functioning as a virtual clinic for the management of MPS II. The Hunter disease eClinic, a self-training, user-friendly educational software program, available at the Lysosomal Storage Research Group (http://www.lysosomalstorageresearch.ca), was developed using the Adobe Flash multimedia platform. It was designed to function both to provide a realistic, interactive virtual clinic and instantaneous access to supporting literature on Hunter disease. The Hunter disease eClinic consists of an eBook and an eClinic. The eClinic is the interactive virtual clinic component of the software. Within an environment resembling a real clinic, the trainee is instructed to perform a medical history, to examine the patient, and to order appropriate investigation. The program provides clinical data derived from the management of actual patients with Hunter disease. The eBook provides instantaneous, electronic access to a vast collection of reference information to provide detailed background clinical and basic science, including relevant biochemistry, physiology, and genetics. In the eClinic, the trainee is presented with quizzes designed to provide immediate feedback on both trainee effectiveness and efficiency. User feedback on the merits of the program was collected at several seminars and formal clinical rounds at several medical centres, primarily in Canada. In addition, online usage statistics were documented for a 2-year period. Feedback was consistently positive and confirmed the practical benefit of the program. The online English-language version is accessed daily by users from all over the world; a Japanese translation of the program is also available. The Hunter disease eClinic employs a CBT model providing the trainee with realistic

Learning from the mistakes of others: How female elk (Cervus elaphus adjust behaviour with age to avoid hunters.

Directory of Open Access Journals (Sweden)

Henrik Thurfjell

Full Text Available In animal behaviour, there is a dichotomy between innate behaviours (e.g., temperament or personality traits versus those behaviours shaped by learning. Innate personality traits are supposedly less evident in animals when confounded by learning acquired with experience through time. Learning might play a key role in the development and adoption of successful anti-predator strategies, and the related adaptation has the potential to make animals that are more experienced less vulnerable to predation. We carried out a study in a system involving a large herbivorous mammal, female elk, Cervus elaphus, and their primary predator, i.e., human hunters. Using fine-scale satellite telemetry relocations, we tested whether differences in behaviour depending on age were due solely to selection pressure imposed by human hunters, meaning that females that were more cautious were more likely to survive and become older. Or whether learning also was involved, meaning that females adjusted their behaviour as they aged. Our results indicated that both human selection and learning contributed to the adoption of more cautious behavioural strategies in older females. Whereas human selection of behavioural traits has been shown in our previous research, we here provide evidence of additive learning processes being responsible for shaping the behaviour of individuals in this population. Female elk are indeed almost invulnerable to human hunters when older than 9-10 y.o., confirming that experience contributes to their survival. Female elk monitored in our study showed individually changing behaviours and clear adaptation as they aged, such as reduced movement rates (decreased likelihood of encountering human hunters, and increased use of secure areas (forest and steeper terrain, especially when close to roads. We also found that elk adjusted behaviours depending on the type of threat (bow and arrow vs. rifle hunters. This fine-tuning by elk to avoid hunters, rather

Levels and sources of forest fire prevention knowledge of California hunters

Science.gov (United States)

William S. Folkman

1963-01-01

Males 30-50 years of age from the smaller urban centers (under 25,000 population) make up the bulk of the California hunter population. They are mainly from the skilled-semiskilled and professional-managerial occupations. Their level of knowledge about forest fire prevention is generally high, but their knowledge is weak in some pertinent areas. Most frequently...

Favorable ecological circumstances promote life expectancy in chimpanzees similar to that of human hunter-gatherers.

Science.gov (United States)

Wood, Brian M; Watts, David P; Mitani, John C; Langergraber, Kevin E

2017-04-01

Demographic data on wild chimpanzees are crucial for understanding the evolution of chimpanzee and hominin life histories, but most data come from populations affected by disease outbreaks and anthropogenic disturbance. We present survivorship data from a relatively undisturbed and exceptionally large community of eastern chimpanzees (Pan troglodytes schweinfurthii) at Ngogo, Kibale National Park, Uganda. We monitored births, deaths, immigrations, and emigrations in the community between 1995 and 2016. Using known and estimated ages, we calculated survivorship curves for the whole community, for males and females separately, and for individuals ≤2 years old when identified. We used a novel method to address age estimation error by calculating stochastic survivorship curves. We compared Ngogo life expectancy, survivorship, and mortality rates to those from other chimpanzee communities and human hunter-gatherers. Life expectancy at birth for both sexes combined was 32.8 years, far exceeding estimates of chimpanzee life expectancy in other communities, and falling within the range of human hunter-gatherers (i.e., 27-37 years). Overall, the pattern of survivorship at Ngogo was more similar to that of human hunter-gatherers than to other chimpanzee communities. Maximum lifespan for the Ngogo chimpanzees, however, was similar to that reported at other chimpanzee research sites and was less than that of human-hunter gatherers. The absence of predation by large carnivores may contribute to some of the higher survivorship at Ngogo, but this cannot explain the much higher survivorship at Ngogo than at Kanyawara, another chimpanzee community in the same forest, which also lacks large carnivores. Higher survivorship at Ngogo appears to be an adaptive response to a food supply that is more abundant and varies less than that of Kanyawara. Future analyses of hominin life history evolution should take these results into account. Copyright © 2017 Elsevier Ltd. All rights

The seed hunter in het spoor van Vavilov (interview met C. Kik)

NARCIS (Netherlands)

Zanderink, R.; Kik, C.

2013-01-01

Er moet voor een veredelaar een grote variatie aan plantmateriaal aanwezig zijn om uit te kunnen putten zodat onze gewassen, die vaak bestaan uit monoculturen, voor de toekomst veiliggesteld worden. Het vinden van die variatie is het werk van seed hunters of zadenverzamelaars. Eén van die seed

The hunter a scientific novel

CERN Document Server

Genta, Giancarlo

2013-01-01

The 24th century: humankind has become a spacefaring civilization, colonizing the solar system and beyond. While no alien forms of life have yet been encountered in this expansion into space, colonists suddenly encounter machines of alien origin - huge robots able to reproduce themselves.  Called replicators by the colonists, they seem to have but a single goal: to destroy all organic life they come in contact with. Since the colonial governments have no means to fight this menace directly, they instead promise huge rewards to whoever destroys a replicator. As a result, the frontier attracts a new kind of adventurers, the Hunters, who work to find and destroy the replicators. Mike Edwards, a skilled young maintenance technician and robotics expert at a faraway outpost, will not only become one of them - but be the very first one to unlock the secret behind the replicators’ origin and mission.   The scientific and technical aspects underlying the plot - in particular space travel, robotics and self-replica...

Shooting history and presence of high-frequency hearing impairment in swedish hunters: A cross-sectional internet-based observational study.

Science.gov (United States)

Honeth, Louise; Ström, Peter; Ploner, Alexander; Bagger-Sjöbäck, Dan; Rosenhall, Ulf; Nyrén, Olof

2015-01-01

The aim of this cross-sectional study among Swedish hunters was to examine the association between shooting history and presence of high-frequency hearing impairment (HFHI). All hunters registered with an e-mail address in the membership roster of the Swedish Hunters' Association were invited via e-mail to a secure website with a questionnaire and an Internet-based audiometry test. Associations, expressed as prevalence ratio (PR), were multivariately modelled using Poisson regression. The questionnaire was answered by 1771 hunters (age 11-91 years), and 202 of them also completed the audiometry test. Subjective severe hearing loss was reported by 195/1771 (11%), while 23/202 (11%) exhibited HFHI upon testing with Internet-based audiometry. As many as 328/1771 (19%) had never used hearing protection during hunting. In the preceding 5 years, 785/1771 (45%), had fired >6 unprotected gunshots with hunting rifle calibers. The adjusted PR of HFHI when reporting 1-6 such shots, relative to 0, was 1.5 [95% confidence interval (CI) 1.1-2.1; P = 0.02]. We could not verify any excessive HFHI prevalence among 89 hunters reporting unprotected exposure to such gunshot noise >6 times. Nor did the total number of reported rifle shots seem to matter. These findings support the notion of a wide variation in individual susceptibility to impulse noise; that significant sound energy, corresponding to unprotected noise from hunting rifle calibers, seems to be required; that susceptible individuals may sustain irreversible damage to the inner ear from just one or a few shots; and that use of hearing protection should be encouraged from the first shot with such weapons.

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

Directory of Open Access Journals (Sweden)

W Randall Haas

Full Text Available 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.

The genetics of an early Neolithic pastoralist from the Zagros, Iran

KAUST Repository

Gallego-Llorente, M.

2016-08-09

The agricultural transition profoundly changed human societies. We sequenced and analysed the first genome (1.39x) of an early Neolithic woman from Ganj Dareh, in the Zagros Mountains of Iran, a site with early evidence for an economy based on goat herding, ca. 10,000 BP. We show that Western Iran was inhabited by a population genetically most similar to hunter-gatherers from the Caucasus, but distinct from the Neolithic Anatolian people who later brought food production into Europe. The inhabitants of Ganj Dareh made little direct genetic contribution to modern European populations, suggesting those of the Central Zagros were somewhat isolated from other populations of the Fertile Crescent. Runs of homozygosity are of a similar length to those from Neolithic farmers, and shorter than those of Caucasus and Western Hunter-Gatherers, suggesting that the inhabitants of Ganj Dareh did not undergo the large population bottleneck suffered by their northern neighbours. While some degree of cultural diffusion between Anatolia, Western Iran and other neighbouring regions is possible, the genetic dissimilarity between early Anatolian farmers and the inhabitants of Ganj Dareh supports a model in which Neolithic societies in these areas were distinct.

The genetics of an early Neolithic pastoralist from the Zagros, Iran

KAUST Repository

Gallego-Llorente, M.; Connell, S.; Jones, E. R.; Merrett, D. C.; Jeon, Y.; Eriksson, Anders; Siska, V.; Gamba, C.; Meiklejohn, C.; Beyer, R.; Jeon, S.; Cho, Y. S.; Hofreiter, M.; Bhak, J.; Manica, A.; Pinhasi, R.

2016-01-01

The agricultural transition profoundly changed human societies. We sequenced and analysed the first genome (1.39x) of an early Neolithic woman from Ganj Dareh, in the Zagros Mountains of Iran, a site with early evidence for an economy based on goat herding, ca. 10,000 BP. We show that Western Iran was inhabited by a population genetically most similar to hunter-gatherers from the Caucasus, but distinct from the Neolithic Anatolian people who later brought food production into Europe. The inhabitants of Ganj Dareh made little direct genetic contribution to modern European populations, suggesting those of the Central Zagros were somewhat isolated from other populations of the Fertile Crescent. Runs of homozygosity are of a similar length to those from Neolithic farmers, and shorter than those of Caucasus and Western Hunter-Gatherers, suggesting that the inhabitants of Ganj Dareh did not undergo the large population bottleneck suffered by their northern neighbours. While some degree of cultural diffusion between Anatolia, Western Iran and other neighbouring regions is possible, the genetic dissimilarity between early Anatolian farmers and the inhabitants of Ganj Dareh supports a model in which Neolithic societies in these areas were distinct.

The genetics of an early Neolithic pastoralist from the Zagros, Iran

KAUST Repository

Gallego Llorente, Marcos; Connell, Sarah; Jones, Eppie R; Merrett, Deborah; Jeon, Jeonsu; Eriksson, Anders; Siska, Veronika; Gamba, Cristina; Meiklejohn, Chris; Beyer, Robert; Jeon, Sungwon; Cho, Yung Sung; Hofreiter, Michael; Bhak, Jong; Manica, Andrea; Pinhasi, Ron

2016-01-01

The agricultural transition profoundly changed human societies. We sequenced and analysed the first genome (1.39x) of an early Neolithic woman from Ganj Dareh, in the Zagros Mountains of Iran, a site with early evidence for an economy based on goat herding,ca. 10,000 BP. We show that Western Iran was inhabited by a population genetically most similar to hunter-gatherers from the Caucasus, but distinct from the Neolithic Anatolian people who later brought food production into Europe. The inhabitants of Ganj Dareh made little direct genetic contribution to modern European populations, suggesting they were somewhat isolated from other populations in the region. Runs of homozygosity are of a similar length to those from Neolithic Anatolians, and shorter than those of Caucasus and Western Hunter-Gatherers, suggesting that the inhabitants of Ganj Dareh did not undergo the large population bottleneck suffered by their northern neighbours. While some degree of cultural diffusion between Anatolia, Western Iran and other neighbouring regions is possible, the genetic dissimilarity of early Anatolian farmers and the inhabitants of Ganj Dareh supports a model in which Neolithic societies in these areas were distinct.

The genetics of an early Neolithic pastoralist from the Zagros, Iran

KAUST Repository

Gallego Llorente, Marcos

2016-06-18

The agricultural transition profoundly changed human societies. We sequenced and analysed the first genome (1.39x) of an early Neolithic woman from Ganj Dareh, in the Zagros Mountains of Iran, a site with early evidence for an economy based on goat herding,ca. 10,000 BP. We show that Western Iran was inhabited by a population genetically most similar to hunter-gatherers from the Caucasus, but distinct from the Neolithic Anatolian people who later brought food production into Europe. The inhabitants of Ganj Dareh made little direct genetic contribution to modern European populations, suggesting they were somewhat isolated from other populations in the region. Runs of homozygosity are of a similar length to those from Neolithic Anatolians, and shorter than those of Caucasus and Western Hunter-Gatherers, suggesting that the inhabitants of Ganj Dareh did not undergo the large population bottleneck suffered by their northern neighbours. While some degree of cultural diffusion between Anatolia, Western Iran and other neighbouring regions is possible, the genetic dissimilarity of early Anatolian farmers and the inhabitants of Ganj Dareh supports a model in which Neolithic societies in these areas were distinct.

Structure of the crust beneath Cameroon, West Africa, from the joint inversion of Rayleigh wave group velocities and receiver functions

Science.gov (United States)

Tokam, Alain-Pierre K.; Tabod, Charles T.; Nyblade, Andrew A.; Julià, Jordi; Wiens, Douglas A.; Pasyanos, Michael E.

2010-11-01

The Cameroon Volcanic Line (CVL) consists of a linear chain of Tertiary to Recent, generally alkaline, volcanoes that do not exhibit an age progression. Here we study crustal structure beneath the CVL and adjacent regions in Cameroon using 1-D shear wave velocity models obtained from the joint inversion of Rayleigh wave group velocities and P-receiver functions for 32 broad-band seismic stations deployed between 2005 January and 2007 February. We find that (1) crustal thickness (35-39km) and velocity structure is similar beneath the CVL and the Pan African Oubanguides Belt to the south of the CVL, (2) crust is thicker (43-48km) under the northern margin of the Congo Craton and is characterized by shear wave velocities >=4.0kms-1 in its lower part and (3) crust is thinner (26-31km) under the Garoua rift and the coastal plain. In addition, a fast velocity layer (Vs of 3.6-3.8kms-1) in the upper crust is found beneath many of the seismic stations. Crustal structure beneath the CVL and the Oubanguides Belt is very similar to Pan African crustal structure in the Mozambique Belt, and therefore it appears not to have been modified significantly by the magmatic activity associated with the CVL. The crust beneath the coastal plain was probably thinned during the opening of the southern Atlantic Ocean, while the crust beneath the Garoua rift was likely thinned during the formation of the Benue Trough in the early Cretaceous. We suggest that the thickened crust and the thick mafic lower crustal layer beneath the northern margin of the Congo Craton may be relict features from a continent-continent collision along this margin during the formation of Gondwana.

Coccidioidomycosis in armadillo hunters from the state of Ceará, Brazil

OpenAIRE

Brillhante, Raimunda Sâmia Nogueira; Moreira Filho, Renato Evando; Rocha, Marcos Fábio Gadelha; Castelo-Branco, Débora de Souza Collares Maia; Fechine, Maria Auxiliadora Bezerra; Lima, Rita Amanda Chaves de; Picanço, Yuri Vieira Cunha; Cordeiro, Rossana de Aguiar; Camargo, Zoilo Pires de; Queiroz, José Ajax Nogueira; Araujo, Roberto Wagner Bezerra de; Mesquita, Jacó Ricarte Lima de; Sidrim, José Júlio Costa

2012-01-01

Coccidioidomycosis is a systemic mycosis with a variable clinical presentation. Misdiagnosis of coccidioidomycosis as bacterial pneumopathy leads to inappropriate prescription of antibiotics and delayed diagnosis. This report describes an outbreak among armadillo hunters in northeastern Brazil in which an initial diagnosis of bacterial pneumonia was later confirmed as coccidioidomycosis caused by Coccidioides posadasii. Thus, this mycosis should be considered as an alternative diagnosis in pa...

Human behavior. Sex equality can explain the unique social structure of hunter-gatherer bands.

Science.gov (United States)

Dyble, M; Salali, G D; Chaudhary, N; Page, A; Smith, D; Thompson, J; Vinicius, L; Mace, R; Migliano, A B

2015-05-15

The social organization of mobile hunter-gatherers has several derived features, including low within-camp relatedness and fluid meta-groups. Although these features have been proposed to have provided the selective context for the evolution of human hypercooperation and cumulative culture, how such a distinctive social system may have emerged remains unclear. We present an agent-based model suggesting that, even if all individuals in a community seek to live with as many kin as possible, within-camp relatedness is reduced if men and women have equal influence in selecting camp members. Our model closely approximates observed patterns of co-residence among Agta and Mbendjele BaYaka hunter-gatherers. Our results suggest that pair-bonding and increased sex egalitarianism in human evolutionary history may have had a transformative effect on human social organization. Copyright © 2015, American Association for the Advancement of Science.

Establishment of native and exotic grasses on mine overburden and topsoil in the Hunter Valley, New South Wales

Energy Technology Data Exchange (ETDEWEB)

Huxtable, C.H.A.; Koen, T.B.; Waterhouse, D. [DNR, Dangar, NSW (Australia)

2005-07-01

Current recommendations for rehabilitation of open-cut coal mines in the Hunter Valley involve the sowing of exotic pasture species to reinstate mined land to Class IV and V under the Rural Land Capability System. Despite the importance of native grasses in the pre-mined landscape, they are currently not widely included in mine rehabilitation. To address this issue a project was conducted between 1994 and 2000 to research the use of native grasses for rehabilitation of open-cut coal mines in the Hunter Valley. This paper reports on 2 mine site experiments that aimed to assess establishment and persistence of a broad range of native and exotic grass species from an autumn sowing in both topsoil and raw spoil over a period of 61 months. The most promising natives in terms of early establishment, persistence and spread over time, included six C-3 accessions (five Austrodanthonia spp. and Austrostipa bigeniculata) and one C-4 accession (Cynodon dactylon). Persistence of these accessions was better in raw spoil than topsoil, despite initial low numbers, due to a lack of weed competition and their ability to spread by self-seeding. In topsoil, and in the absence of any biomass reduction, native species were mostly out-competed by vigorous exotic perennial grasses which were sown in these experiments and from seed influx from adjacent rehabilitation areas or from the soil seed bank. The effects of climatic conditions and differences in soil physical, chemical and seed bank characteristics at the 2 mine sites are also discussed.

"Founder crops" v. wild plants: Assessing the plant-based diet of the last hunter-gatherers in southwest Asia

Science.gov (United States)

Arranz-Otaegui, Amaia; González Carretero, Lara; Roe, Joe; Richter, Tobias

2018-04-01

The Natufian culture (c. 14.6-11.5 ka cal. BP) represents the last hunter-gatherer society that inhabited southwest Asia before the development of plant food production. It has long been suggested that Natufians based their economy on the exploitation of the wild ancestors of the Neolithic "founder crops", and that these hunter-gatherers were therefore on the "threshold to agriculture". In this work we review the available data on Natufian plant exploitation and we report new archaeobotanical evidence from Shubayqa 1, a Natufian site located in northeastern Jordan (14.6-11.5 ka cal. BP). Shubayqa 1 has produced an exceptionally large plant assemblage, including direct evidence for the continuous exploitation of club-rush tubers (often regarded as "missing foods") and other wild plants, which were probably used as food, fuel and building materials. Taking together this data we evaluate the composition of archaeobotanical assemblages (plant macroremains) from the Natufian to the Early Pre-Pottery Neolithic B (EPPNB). Natufian assemblages comprise large proportions of non-founder plant species (>90% on average), amongst which sedges, small-seeded grasses and legumes, and fruits and nuts predominate. During the Pre-Pottery Neolithic, in particular the EPPNB, the presence of "founder crops" increases dramatically and constitute up to c. 42% of the archaeobotanical assemblages on average. Our results suggest that plant exploitation strategies during the Natufian were very different from those attested during subsequent Neolithic periods. We argue that historically driven interpretations of the archaeological record have over-emphasized the role of the wild ancestors of domesticated crops previous to the emergence of agriculture.

Evidence of Levy walk foraging patterns in human hunter-gatherers.

Science.gov (United States)

Raichlen, David A; Wood, Brian M; Gordon, Adam D; Mabulla, Audax Z P; Marlowe, Frank W; Pontzer, Herman

2014-01-14

When searching for food, many organisms adopt a superdiffusive, scale-free movement pattern called a Lévy walk, which is considered optimal when foraging for heterogeneously located resources with little prior knowledge of distribution patterns [Viswanathan GM, da Luz MGE, Raposo EP, Stanley HE (2011) The Physics of Foraging: An Introduction to Random Searches and Biological Encounters]. Although memory of food locations and higher cognition may limit the benefits of random walk strategies, no studies to date have fully explored search patterns in human foraging. Here, we show that human hunter-gatherers, the Hadza of northern Tanzania, perform Lévy walks in nearly one-half of all foraging bouts. Lévy walks occur when searching for a wide variety of foods from animal prey to underground tubers, suggesting that, even in the most cognitively complex forager on Earth, such patterns are essential to understanding elementary foraging mechanisms. This movement pattern may be fundamental to how humans experience and interact with the world across a wide range of ecological contexts, and it may be adaptive to food distribution patterns on the landscape, which previous studies suggested for organisms with more limited cognition. Additionally, Lévy walks may have become common early in our genus when hunting and gathering arose as a major foraging strategy, playing an important role in the evolution of human mobility.

HiggsHunters - a citizen science project for ATLAS

CERN Document Server

AUTHOR|(INSPIRE)INSPIRE-00053405; The ATLAS collaboration

2017-01-01

Since the launch of HiggsHunters.org in November 2014, citizen science volunteers have classified more than a million points of interest in images from the ATLAS experiment at the LHC. Volunteers have been looking for displaced vertices and unusual features in images recorded during LHC Run-1. We discuss the design of the project, its impact on the public, and the results of how the human volunteers performed relative to the computer algorithms in identifying displaced secondary vertices. People were better than existing algorithms at identifying displaced vertices for some masses and lifetimes, and showed good ability to recognize unexpected new features in the data.

Deer hunting and television: are tv shows creating expectations among deer hunters?

Science.gov (United States)

Joshua D. Agee; Craig A. Miller

2009-01-01

Throughout the past two decades new media outlets emphasizing trophy deer hunting have come to dominate hunting culture. Using data collected through a mail survey of Illinois deer hunters (n = 2,683, 78.5-percent response), we tested two hypotheses to determine factors that contribute to preference for hunting trophy deer. In particular, we examined the relationship...

Cadmium, lead, and chromium in large game: a local-scale exposure assessment for hunters consuming meat and liver of wild boar.

Science.gov (United States)

Danieli, P P; Serrani, F; Primi, R; Ponzetta, M P; Ronchi, B; Amici, A

2012-11-01

Heavy metals are ubiquitous in soil, water, and air. Their entrance into the food chain is an important environmental issue that entails risks to humans. Several reports indicate that game meat can be an important source of heavy metals, particularly because of the increasing consumption of game meat, mainly by hunters. We performed an exposure assessment of hunters and members of their households, both adults and children, who consumed wild boar (WB) meat and offal. We estimated the amount of cadmium, lead, and chromium in the tissues of WB hunted in six areas within Viterbo Province (Italy) and gathered data on WB meat and offal consumption by conducting specific diet surveys in the same areas. The exposure to cadmium, lead, and chromium was simulated with specifically developed Monte Carlo simulation models. Cadmium and lead levels in WB liver and meat harvested in Viterbo Province (Italy) were similar to or lower than the values reported in other studies. However, some samples contained these metals at levels greater then the EU limits set for domestic animals. The chromium content of meat or liver cannot be evaluated against any regulatory limit, but our results suggest that the amounts of this metal found in WB products may reflect a moderate environmental load. Our survey of the hunter population confirmed that their consumption of WB meat and liver was greater than that of the general Italian population. This level of consumption was comparable with other European studies. Consumption of WB products contributes significantly to cadmium and lead exposure of both adults and children. More specifically, consumption of the WB liver contributed significantly to total cadmium and lead exposure of members of the households of WB hunters. As a general rule, liver consumption should be kept to a minimum, especially for children living in these hunter households. The exposure to chromium estimated for this population of hunters may be considered to be safe. However

Blood, guts and knife cuts: reducing the risk of swine brucellosis in feral pig hunters in north-west New South Wales, Australia.

Science.gov (United States)

Massey, P D; Polkinghorne, B G; Durrheim, D N; Lower, T; Speare, R

2011-01-01

Humans who have close contact with livestock, wild or feral animals can risk acquiring zoonotic infections such as brucellosis, Q fever, and leptospirosis. Human infection with Brucella suis (swine brucellosis) usually follows occupational or recreational exposure to infected animals. Worldwide, many cases of human infection follow contact with infected feral pigs. In Australia there is a growing market for the export of 'wild boar' and a considerable number of people are involved in feral pig hunting. However, feral pig hunters are often hard to reach with health strategies. According to Australian authorities the most important means of preventing disease in humans includes covering cuts; wearing gloves; washing hands; and avoiding blood when coming into contact with feral pigs. There has not been an evaluation of the acceptability of these recommended risk-reduction strategies in the settings where feral pig hunting and evisceration occurs. Semi-structured interviews and small focus groups were conducted with feral pig hunters in north-west New South Wales (NSW), Australia, to explore their hunting experiences and views on the brucellosis prevention strategies. Interview and focus group notes were thematically analysed. There was a range of experiences of feral pig hunting, from a very professional approach to a purely recreational approach. The main domains that emerged from participants' experiences during their most recent feral pig hunting activity and their reflections on current swine brucellosis risk reduction strategies were: 'you've gotta be tough to be a feral pig hunter'; 'most of the suggested strategies won't work as they are'; 'reducing risk in the scrub'; and 'how to let pig hunters know'. The recreational nature and prevailing macho perspective of participants demand a pragmatic approach to risk reduction if it is going to prove acceptable to feral pig hunters. The 'you've gotta be tough to be a feral pig hunter' context of the activity and the

Depth variations of P-wave azimuthal anisotropy beneath East Asia

Science.gov (United States)

Wei, W.; Zhao, D.; Xu, J.

2017-12-01

We present a new P-wave anisotropic tomographic model beneath East Asia by inverting a total of 1,488,531 P wave arrival-time data recorded by the regional seismic networks in East Asia and temporary seismic arrays deployed on the Tibetan Plateau. Our results provide important new insights into the subducting Indian, Pacific and Philippine Sea plates and mantle dynamics in East Asia. Our tomographic images show that the northern limit of the subducting Indian plate has reached the Jinsha River suture in eastern Tibet. A striking variation of P-wave azimuthal anisotropy is revealed in the Indian lithosphere: the fast velocity direction (FVD) is NE-SW beneath the Indian continent, whereas the FVD is arc parallel beneath the Himalaya and Tibetan Plateau, which may reflect re-orientation of minerals due to lithospheric extension, in response to the India-Eurasia collision. The FVD in the subducting Philippine Sea plate beneath the Ryukyu arc is NE-SW(trench parallel), which is consistent with the spreading direction of the West Philippine Basin during its initial opening stage, suggesting that it may reflect the fossil anisotropy. A circular pattern of FVDs is revealed around the Philippine Sea slab beneath SE China. We suggest that it reflects asthenospheric strain caused by toroidal mantle flow around the edge of the subducting slab. We find a striking variation of the FVD with depth in the subducting Pacific slab beneath the Northeast Japan arc. It may be caused by slab dehydration that changed elastic properties of the slab with depth. The FVD in the mantle wedge beneath the Northeast Japan and Ryukyu arcs is trench normal, which reflects subduction-induced convection. Beneath the Kuril and Izu-Bonin arcs where oblique subduction occurs, the FVD in the mantle wedge is nearly normal to the moving direction of the downgoing Pacific plate, suggesting that the oblique subduction together with the complex slab morphology have disturbed the mantle flow.

Period Determination of Binary Asteroid Targets Observed at Hunters Hill Observatory: May-September 2009

Science.gov (United States)

Higgins, David; Oey, Julian; Pravec, Petr

2011-01-01

Lightcurves for seven confirmed or possible binary asteroids were obtained at the Hunters Hill Observatory (HHO) and Leura Observatory from 2009 May through 2010 September: 1453 Fennia, 2501 Lohja, 3076 Garbor, 4029 Bridges, 5325 Silver, 6244 Okamoto, and (6265) 1985 TW3.

From Head-hunter to Organ-thief: Verisimilitude, Doubt and Plausible Worlds in Indonesia and Beyond

DEFF Research Database (Denmark)

Bubandt, Nils Ole

2017-01-01

their victims and using the human heads in construction rituals as they used to do, head-hunters are now allegedly harvesting the victims’ organs for sale on the international organ market. Based on a comparison of ethnographic material from North Maluku, a province in the eastern part of Indonesia, and news...... reports I trace the shift from head-hunting to organ theft and suggest that this plasticity is not merely a symbolic representation of changing political and economic realities. Rather, I argue, the organ-stealing head-hunters are part of a global travelling package that includes and entangles organ...... trafficking practices, media accounts, political imaginaries, and social anxieties within the same field of reality and possibility, a field of verisimilitude in which fiction and fact, rumour and reality, are fundamentally blurred. The article proposes a ‘more-than-representational’ approach to the organ...

3-D crustal structure beneath the southern Korean Peninsula from local earthquakes

Science.gov (United States)

Kim, K. H.; Park, J. H.; Park, Y.; Hao, T.; Kang, S. Y.; Kim, H. J.

2017-12-01

Located at the eastern margin of the Eurasian continent, the geology and tectonic evolution of the Korean Peninsula are closely related to the rest of the Asian continent. Although the widespread deformation of eastern Asia and its relation to the geology and tectonics of the Korean Peninsula have been extensively studied, the answers to many fundamental questions about the peninsula's history remain inconclusive. The three-dimensional subsurface structure beneath the southern Korean Peninsula is poorly known, even though such information could be key in verifying or rejecting several competing models of the tectonic evolution of East Asia. We constructed a three-dimensional velocity model of the upper crust beneath the southern Korean Peninsula using 19,935 P-wave arrivals from 747 earthquakes recorded by high-density local seismic networks maintained by Korea Meteorological Administration and Korea Institute of Geosciences and Mineral Resources. Results show significant lateral and vertical variations: velocity increases from northwest to southeast at shallow depths, and significant velocity variations are observed across the South Korea Tectonic Line between the Okcheon Fold Belt and the Youngnam Massif. Collision between the North China and South China blocks during the Early Cretaceous might have caused extensive deformation and the observed negative velocity anomalies in the region. The results of the tomographic inversion, combined with the findings of previous studies of Bouguer and isostatic gravity anomalies, indicate the presence of high-density material in the upper and middle crust beneath the Gyeongsang Basin in the southeastern Korean Peninsula. Although our results partially support the indentation tectonic model, it is still premature to discard other tectonic evolution models because our study only covers the southern half of the peninsula.

Deformation in D″ Beneath North America From Anisotropy

Science.gov (United States)

Nowacki, A. J.; Wookey, J.; Kendall, J. M.

2009-12-01

The lowermost few hundred kilometres of the Earth's mantle—known as D″—form the boundary between it and the core below, control the Earth's convective system, and are the site of probable large thermochemical heterogeneity. Seismic observations of D″ show a strong heterogeneity in seismic wave velocity and significant seismic anisotropy (the variation of wave speed with direction) are present in many parts of the region. On the basis of continuous regions of fast shear velocity (VS) anomalies in global models, it is also proposed as the resting place of subducted slabs, notably the Farallon beneath North America. A phase change of MgSiO3-perovskite (pv) to a post-perovskite (ppv) structure at near-core-mantle boundary (CMB) conditions is a compelling mechanism to explain the seismic features of D″. An outstanding question is how this and other mineral phases may deform to produce anisotropy, with different mechanisms possible. With knowledge either of mantle flow or which slip system is responsible for causing deformation, we can potentially determine the other with observations of the resulting seismic anisotropy. We investigate the dynamics at the CMB beneath North America using differential shear wave splitting in S and ScS phases from earthquakes of magnitude MW>5.5 in South and Central America, Hawaii the Mid-Atlantic Ridge and East Pacific Rise. They are detected on ~500 stations in North America, giving ~700 measurements of anisotropy in D″. We achieve this by correcting for anisotropy in the upper mantle (UM) beneath both the source and receiver. The measurements cover three regions beneath western USA, the Yucatan peninsula and Florida. In each case, two different, crossing ray paths are used, so that the style of anisotropy can be constrained—a single azimuth cannot distinguish differing cases. Our results showing ~1% anisotropy dependent on azimuth are not consistent with transverse isotropy with a vertical symmetry axis (VTI) anywhere. The

Assessment of risk to aquatic biota from elevated salinity -- a case study from the Hunter River, Australia.

Science.gov (United States)

Muschal, Monika

2006-05-01

An ecological risk assessment was performed on salinity levels of the Hunter River and its tributaries to respond to concerns that high salinity may be damaging aquatic ecosystems. Probabilistic techniques were used to assess likelihood and consequence, and hence the risk to aquatic biota from salinity. Continuous electrical conductivity distributions were used to describe the likelihood that high salinity would occur (exposure dataset) and toxicity values were compiled from the limited literature sources available to describe the consequence of high salinity (effects dataset). The assessment was preliminary in the sense that it modelled risk on the basis of existing data and did not undertake site-specific toxicity testing. Some sections of the Hunter River catchment have geologies that are saline because of their marine origins. Catchment development has increased the liberation rates of salts into surface-waters. Such modifying activities include coal-mining, power generation and land clearing. The aquatic biota of tributaries had a greater risk of impairment from high salinity than that of the Hunter River. High salinities in the tributaries were attributed to the combined factors of naturally saline geologies, increased liberation of salts due to modification of the landscape, and reduced dilution by flushing flows. A salinity guideline trigger value of 1100 mg L(-1) was recommended.

Soil property control of biogeochemical processes beneath two subtropical stormwater infiltration basins.

Science.gov (United States)

O'Reilly, Andrew M; Wanielista, Martin P; Chang, Ni-Bin; Harris, Willie G; Xuan, Zhemin

2012-01-01

Substantially different biogeochemical processes affecting nitrogen fate and transport were observed beneath two stormwater infiltration basins in north-central Florida. Differences are related to soil textural properties that deeply link hydroclimatic conditions with soil moisture variations in a humid, subtropical climate. During 2008, shallow groundwater beneath the basin with predominantly clayey soils (median, 41% silt+clay) exhibited decreases in dissolved oxygen from 3.8 to 0.1 mg L and decreases in nitrate nitrogen (NO-N) from 2.7 mg L to soils (median, 2% silt+clay), aerobic conditions persisted from 2007 through 2009 (dissolved oxygen, 5.0-7.8 mg L), resulting in NO-N of 1.3 to 3.3 mg L in shallow groundwater. Enrichment of δN and δO of NO combined with water chemistry data indicates denitrification beneath the clayey basin and relatively conservative NO transport beneath the sandy basin. Soil-extractable NO-N was significantly lower and the copper-containing nitrite reductase gene density was significantly higher beneath the clayey basin. Differences in moisture retention capacity between fine- and coarse-textured soils resulted in median volumetric gas-phase contents of 0.04 beneath the clayey basin and 0.19 beneath the sandy basin, inhibiting surface/subsurface oxygen exchange beneath the clayey basin. Results can inform development of soil amendments to maintain elevated moisture content in shallow soils of stormwater infiltration basins, which can be incorporated in improved best management practices to mitigate NO impacts. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Elastic and Anelastic Structure Beneath Eurasia

National Research Council Canada - National Science Library

Ekstrom, Goran

1997-01-01

The primary objective of this work has been to map the variations of elastic mantle properties beneath Eurasia over horizontal length scales of approximately 1000-1500 kilometers and vertial length...

Indice de Indices en la Biblioteca de Hunter College para el Estudiante Hispano.

Science.gov (United States)

Talero Bielsa, Alberto; And Others

Designed for Spanish-speaking students of Hunter College of the City University of New York, this guide explains the use of 70 English-language indexes found in the college library. The explanations are given in Spanish in order to simplify the process of library research for students who are not completely comfortable with English. Each index is…

Near-source surface seismic measurements for the NPE, NPE Calibration, Hunter`s Trophy, and Mineral Quarry

Energy Technology Data Exchange (ETDEWEB)

Reinke, R.E.; Leverette, J.A. [Field Command Defense Nuclear Agency, Kirtland AFB, NM (United States); Stump, B.W. [Los Alamos National Laboratory, NM (United States)] [and others

1994-12-31

An extensive seismic network was deployed on the surface of Rainier Mesa for both the Non-Proliferation Experiment (NPE) Calibration shot as well as the full scale NPE event. This network was very similar to previous deployments for the nuclear events MISTY ECHO, MINERAL QUARRY, and HUNTERS TROPHY. For the full scale NPE event three-component accelerometers and seismometers were fielded at 32 sites across the mesa. A slightly smaller network with 28 stations was in operation for the 300 pound NPE calibration event. The mesa top array included both accelerometers and seismometers. The accelerometers were used to obtain data from the main NPE event while the seismometers with their higher sensitivity were used to record the 300 pound cal shot and several hundred after events from the NPE. Large spatial variations in ground motion are evident in both the full mesa data set as well as a small (80 m on a side) aperture, 9-element triangular array. This paper summarizes the data and discusses wave propagation effects. A companion paper presents a comparative source analysis.

Do individual differences in use of cover habitat affect red deer`s (Cervus elaphus) probability of being shot by hunters?

OpenAIRE

Stamnes, Inga

2014-01-01

The purpose of this study was to test if red deer (Cervus elaphus) habitat use affects their risk of being shot by hunters. I compared habitat use of 20 GPS-marked red deer that survived the hunting season with 20 individuals that were shot. I predicted that shot red deer used open areas within forested habitats with a better visibility for hunters than surviving red deer. I also predicted that the use of less risky habitat is costly in terms of foraging opportunity, with shot animals using b...

Crustal structure beneath Eastern Greenland

DEFF Research Database (Denmark)

Reiche, Sönke; Thybo, H.; Kaip, G.

2011-01-01

is recorded by 350 Reftek Texan receivers for 10 equidistant shot points along the profile. We use forward ray tracing modelling to construct a two-dimensional velocity model from the observed travel times. These results show the first images of the subsurface velocity structure beneath the Greenland ice...

Turbulence beneath finite amplitude water waves

Energy Technology Data Exchange (ETDEWEB)

Beya, J.F. [Universidad de Valparaiso, Escuela de Ingenieria Civil Oceanica, Facultad de Ingenieria, Valparaiso (Chile); The University of New South Wales, Water Research Laboratory, School of Civil and Environmental Engineering, Sydney, NSW (Australia); Peirson, W.L. [The University of New South Wales, Water Research Laboratory, School of Civil and Environmental Engineering, Sydney, NSW (Australia); Banner, M.L. [The University of New South Wales, School of Mathematics and Statistics, Sydney, NSW (Australia)

2012-05-15

Babanin and Haus (J Phys Oceanogr 39:2675-2679, 2009) recently presented evidence of near-surface turbulence generated below steep non-breaking deep-water waves. They proposed a threshold wave parameter a {sup 2}{omega}/{nu} = 3,000 for the spontaneous occurrence of turbulence beneath surface waves. This is in contrast to conventional understanding that irrotational wave theories provide a good approximation of non-wind-forced wave behaviour as validated by classical experiments. Many laboratory wave experiments were carried out in the early 1960s (e.g. Wiegel 1964). In those experiments, no evidence of turbulence was reported, and steep waves behaved as predicted by the high-order irrotational wave theories within the accuracy of the theories and experimental techniques at the time. This contribution describes flow visualisation experiments for steep non-breaking waves using conventional dye techniques in the wave boundary layer extending above the wave trough level. The measurements showed no evidence of turbulent mixing up to a value of a {sup 2}{omega}/{nu} = 7,000 at which breaking commenced in these experiments. These present findings are in accord with the conventional understandings of wave behaviour. (orig.)

76 FR 46149 - Financial Assistance: Wildlife Restoration, Sport Fish Restoration, Hunter Education and Safety

Science.gov (United States)

2011-08-01

... these regulations on June 10, 2010, to address changes in law, regulation, policy, technology, and... Service 50 CFR Part 80 Financial Assistance: Wildlife Restoration, Sport Fish Restoration, Hunter... 80 [Docket No. FWS-R9-WSR-2009-0088; 91400-5110-POLI-7B; 91400-9410-POLI- 7B] RIN 1018-AW65 Financial...

Gut microbiome of the Hadza hunter-gatherers.

Science.gov (United States)

Schnorr, Stephanie L; Candela, Marco; Rampelli, Simone; Centanni, Manuela; Consolandi, Clarissa; Basaglia, Giulia; Turroni, Silvia; Biagi, Elena; Peano, Clelia; Severgnini, Marco; Fiori, Jessica; Gotti, Roberto; De Bellis, Gianluca; Luiselli, Donata; Brigidi, Patrizia; Mabulla, Audax; Marlowe, Frank; Henry, Amanda G; Crittenden, Alyssa N

2014-04-15

Human gut microbiota directly influences health and provides an extra means of adaptive potential to different lifestyles. To explore variation in gut microbiota and to understand how these bacteria may have co-evolved with humans, here we investigate the phylogenetic diversity and metabolite production of the gut microbiota from a community of human hunter-gatherers, the Hadza of Tanzania. We show that the Hadza have higher levels of microbial richness and biodiversity than Italian urban controls. Further comparisons with two rural farming African groups illustrate other features unique to Hadza that can be linked to a foraging lifestyle. These include absence of Bifidobacterium and differences in microbial composition between the sexes that probably reflect sexual division of labour. Furthermore, enrichment in Prevotella, Treponema and unclassified Bacteroidetes, as well as a peculiar arrangement of Clostridiales taxa, may enhance the Hadza's ability to digest and extract valuable nutrition from fibrous plant foods.

Avian influenza prevalence among hunter-harvested birds in a remote Canadian First Nation community.

Science.gov (United States)

Liberda, Eric N; Meldrum, Richard; Charania, Nadia A; Davey, Robert; Tsuji, Leonard Js

2017-01-01

Avian influenza virus (AIV) prevalence has been associated with wild game and other bird species. The contamination of these birds may pose a greater risk to those who regularly hunt and consumed infected species. Due to resident concerns communicated by local Band Council, hunter-harvested birds from a remote First Nation community in subArctic Ontario, Canada were assessed for AIV. Hunters, and especially those who live a subsistence lifestyle, are at higher risk of AIV exposure due to their increased contact with wild birds, which represent an important part of their diet. Cloacal swabs from 304 harvested game birds representing several species of wild birds commonly hunted and consumed in this First Nation community were analyzed for AIV using real-time reverse transcription polymerase chain reaction. Subtyping was performed using reverse transcription polymerase chain reaction. Sequences were assembled using Lasergene, and the sequences were compared to Genbank. In total, 16 of the 304 cloacal swab samples were positive for AIV. Of the 16 positive samples, 12 were found in mallard ducks, 3 were found in snow geese (wavies), and 1 positive sample was found in partridge. The AIV samples were subtyped, when possible, and found to be positive for the low pathogenic avian influenza virus subtypes H3 and H4. No samples were positive for subtypes of human concern, namely H5 and H7. This work represents the first AIV monitoring program results of hunter-harvested birds in a remote subsistence First Nation community. Community-level surveillance of AIV in remote subsistence hunting communities may help to identify future risks, while educating those who may have the highest exposure about proper handling of hunted birds. Ultimately, only low pathogenic strains of AIV were found, but monitoring should be continued and expanded to safeguard those with the highest exposure risk to AIV.

Sex differences in Nintendo Wii performance as expected from hunter-gatherer selection.

Science.gov (United States)

Cherney, Isabelle D; Poss, Jordan L

2008-06-01

To test the hunter-gatherer theory of cognitive sex differences, men and women each played four video games on a Wii console: two games simulating skills necessary for hunting (navigation and shooting) and two games simulating skills necessary for gathering (fine motor and visual search). Men outperformed women on the two hunting games, whereas there were no sex differences on the gathering skill games. The findings are discussed in terms of evolutionary psychology theory.

High frequency of lactose intolerance in a prehistoric hunter-gatherer population in northern Europe

Directory of Open Access Journals (Sweden)

Holmlund Gunilla

2010-03-01

Full Text Available Abstract Background 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. Results 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%. Conclusions 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.

Seasonal and Long-term Variations in 137Cs Among Adults from Swedish Hunter Families

International Nuclear Information System (INIS)

Agren, G.

2001-01-01

To study seasonal variations in 137 Cs, whole-body content measurements of adults from Swedish hunter families have been performed in autumn 1997 and spring 1998. Measurements were performed in three locations, By, Harbo and Gavle, geographically close (within 100 km of each other) but with large differences in ground deposition levels. The hunter families at these three locations were previously measured in 1994. The measured persons were also asked for their frequency of intake of moose, roe-deer, freshwater fish, mushrooms and berries. A statistically significant lower frequency of intake of mushrooms and berries in By, moose, roe-deer and mushrooms in Harbo, and moose in Gavle was found in springtime compared to autumn. In one of the locations, there was a statistically significant lower average 137 Cs whole-body content in spring 1998 than in autumn 1997 while in the other two locations no such effects could be seen. The 137 Cs whole-body content has decreased by 37% from 1994 and to 1998 (including physical decay) correlated to an effective ecological half time of 6 years. (author)

Teaching Experientially with the Madeline Hunter Method: An Application in a Marketing Research Course

Science.gov (United States)

Burns, Alvin C.

2006-01-01

Due to concerns about the disparity of learning and the high nonresponse rates encountered by student marketing research teams working with sponsors, the author adopted the Hunter Method to restructure his course. This method requires the use of a model onto which students can map their learning via guided practice as well as independent practice.…

Anisotropy tomography beneath east-central China and its geodynamic implications

Science.gov (United States)

Jiang, G.; Zhang, G.

2017-12-01

The east-central China primary consists of the southeastern part of the North China Block (NCB), the Middle-Lower Yangtze Block (MLYB), the northern part of Cathaysia Block (CB) and the Qinling-Dabie-Sulu Orogen (QDSO) (Fig. 1). Previous studies have suggested that both the rich mineralization in MLYB and the ultra-high pressure metamorphic belts in QDSO are closely to the Cretaceous magmatism in the east-central China. For discussing the geodynamic process, we have used the teleseismic tomography to study the 3D P-wave velocity structure down to 800 km deep and proposed a double-slab subduction model. In the present study, we introduce another two parameters representing the azimuthal anisotropy based on the isotropy tomography. Compared with the SKS method, the anisotropy tomography can provide the velocity anisotropy structure in different depths. The new anisotropy results show that (1) high-velocity (high-V) anomalies exist beneath the Middle Yangtze Block (MYB) from 200 km to 700 km depths and beneath the Lower Yangtze Block from 500 km to 700 km depths, and (2) low-velocity (low-V) anomalies exist beneath the Lower Yangtze Block from 50 km to 200 km depths and beneath the CB from 300 km to 700 km depths, respectively, and (3) the fast directions of P-wave velocity at 50-100 km depths are chaotic, however they show some regular changes from 200 km to 600 km depths. At 200-km deep, the fast direction of the low-V beneath the LYB is nearly E-W-trending. With the depth increasing, the fast directions of the low-V beneath the CB from 300 km to 600 km depths change to NEE-trending. In other side, the fast directions of eastern part of the high-V beneath the MYB, close to the low-V beneath the CB, denote NW-trending from 300 km to 600 depths. Combing with previous studies, we explain the high-V and the low-V, mentioned above, as the ancient Yangtze Craton and the upwelling asthenospheric materials, respectively. In addition, the NE-trending fast directions in the

Food Sharing among Hadza Hunter-Gatherer Children.

Directory of Open Access Journals (Sweden)

Alyssa N Crittenden

Full Text Available Human prosociality is one of the defining characteristics of our species, yet the ontogeny of altruistic behavior remains poorly understood. The evolution of widespread food sharing in humans helped shape cooperation, family formation, life history, language, and the development of economies of scale. While the behavioral and ecological correlates of food sharing among adults are widely studied, very little is known about food sharing among children. Here, in the first study to analyze the food sharing patterns of hunter-gatherer children, we show that while sharing may be biased towards kin, reciprocity characterizes the majority of all sharing dyads, both related and unrelated. These data lend support to the recent claim that discrimination among kin might be linked with reciprocal altruism theory. Furthermore, we show that age positively correlates with an increase in sharing, both in frequency and amount, supporting recent suggestions that prosocial behaviors and egalitarianism develop strongly in middle childhood when children acquire the normative rules of their society.

Food Sharing among Hadza Hunter-Gatherer Children.

Science.gov (United States)

Crittenden, Alyssa N; Zes, David A

2015-01-01

Human prosociality is one of the defining characteristics of our species, yet the ontogeny of altruistic behavior remains poorly understood. The evolution of widespread food sharing in humans helped shape cooperation, family formation, life history, language, and the development of economies of scale. While the behavioral and ecological correlates of food sharing among adults are widely studied, very little is known about food sharing among children. Here, in the first study to analyze the food sharing patterns of hunter-gatherer children, we show that while sharing may be biased towards kin, reciprocity characterizes the majority of all sharing dyads, both related and unrelated. These data lend support to the recent claim that discrimination among kin might be linked with reciprocal altruism theory. Furthermore, we show that age positively correlates with an increase in sharing, both in frequency and amount, supporting recent suggestions that prosocial behaviors and egalitarianism develop strongly in middle childhood when children acquire the normative rules of their society.

Coccidioidomycosis in armadillo hunters from the state of Ceará, Brazil.

Science.gov (United States)

Brillhante, Raimunda Sâmia Nogueira; Moreira Filho, Renato Evando; Rocha, Marcos Fábio Gadelha; Castelo-Branco, Débora de Souza Collares Maia; Fechine, Maria Auxiliadora Bezerra; Lima, Rita Amanda Chaves de; Picanço, Yuri Vieira Cunha; Cordeiro, Rossana de Aguiar; Camargo, Zoilo Pires de; Queiroz, José Ajax Nogueira; Araujo, Roberto Wagner Bezerra de; Mesquita, Jacó Ricarte Lima de; Sidrim, José Júlio Costa

2012-09-01

Coccidioidomycosis is a systemic mycosis with a variable clinical presentation. Misdiagnosis of coccidioidomycosis as bacterial pneumopathy leads to inappropriate prescription of antibiotics and delayed diagnosis. This report describes an outbreak among armadillo hunters in northeastern Brazil in which an initial diagnosis of bacterial pneumonia was later confirmed as coccidioidomycosis caused by Coccidioides posadasii. Thus, this mycosis should be considered as an alternative diagnosis in patients reporting symptoms of pneumonia, even if these symptoms are only presented for a short period, who are from areas considered endemic for this disease.

Coccidioidomycosis in armadillo hunters from the state of Ceará, Brazil

Directory of Open Access Journals (Sweden)

Raimunda Sâmia Nogueira Brillhante

2012-09-01

Full Text Available Coccidioidomycosis is a systemic mycosis with a variable clinical presentation. Misdiagnosis of coccidioidomycosis as bacterial pneumopathy leads to inappropriate prescription of antibiotics and delayed diagnosis. This report describes an outbreak among armadillo hunters in northeastern Brazil in which an initial diagnosis of bacterial pneumonia was later confirmed as coccidioidomycosis caused by Coccidioides posadasii. Thus, this mycosis should be considered as an alternative diagnosis in patients reporting symptoms of pneumonia, even if these symptoms are only presented for a short period, who are from areas considered endemic for this disease.

Beyond the drip-line: a high-resolution open-air Holocene hunter-gatherer sequence from highland Lesotho

CSIR Research Space (South Africa)

Mitchell, P

2011-03-01

Full Text Available the drip-line: a high-resolution open-air Holocene hunter-gatherer sequence from highland Lesotho Peter Mitchell1, Ina Plug2, Geoff Bailey3, Ruth Charles4, Amanda Esterhuysen5, Julia Lee Thorp6, Adrian Parker7 & Stephan Woodborne8 The activities...

Surface evolution and carbon sequestration in disturbed and undisturbed wetland soils of the Hunter estuary, southeast Australia

Science.gov (United States)

Howe, A. J.; Rodríguez, J. F.; Saco, P. M.

2009-08-01

The aim of this work was to quantify the soil carbon storage and sequestration rates of undisturbed natural wetlands and disturbed wetlands subject to restriction of tidal flow and subsequent rehabilitation in an Australian estuary. Disturbed and undisturbed estuarine wetlands of the Hunter estuary, New South Wales, Australia were selected as the study sites for this research. Vertical accretion rates of estuarine substrates were combined with soil carbon concentrations and bulk densities to determine the carbon store and carbon sequestration rates of the substrates tested. Relationships between estuary water level, soil evolution and vertical accretion were also examined. The carbon sequestration rate of undisturbed wetlands was lower (15% for mangrove and 55% for saltmarsh) than disturbed wetlands, but the carbon store was higher (65% for mangrove and 60% for saltmarsh). The increased carbon sequestration rate of the disturbed wetlands was driven by substantially higher rates of vertical accretion (95% for mangrove and 345% for saltmarsh). Estuarine wetland carbon stores were estimated at 700-1000 Gg C for the Hunter estuary and 3900-5600 Gg C for New South Wales. Vertical accretion and carbon sequestration rates of estuarine wetlands in the Hunter are at the lower end of the range reported in the literature. The comparatively high carbon sequestration rates reported for the disturbed wetlands in this study indicate that wetland rehabilitation has positive benefits for regulation of atmospheric carbon concentrations, in addition to more broadly accepted ecosystem services.

An improved assay for iduronate 2-sulphate sulphatase in serum and its use in the detection of carriers of the Hunter syndrome

International Nuclear Information System (INIS)

Archer, I.M.; Harper, P.S.; Wusteman, F.S.

1981-01-01

A more sensitive assay procedure has been developed for the enzyme iduronate 2-sulphate sulphatase which is deficient in the Hunter syndrome. The substrate is O-(α-L-idopyranosyluronic acid 2-sulphate)-(1 → 4)-2,5 anhydro-D-[ 3 H-1)mannitol 6-sulphate, which, after incubation, is separated from the product by ion-exchange chromatography on a micro-columnn of Dowex 1 X 2 (Cl - ). Serum analyses can be used to supplement those on hair roots in the detection of carriers of the Hunter syndrome. (Auth.)

Imaging Canary Island hotspot material beneath the lithosphere of Morocco and southern Spain

Science.gov (United States)

Miller, Meghan S.; O'Driscoll, Leland J.; Butcher, Amber J.; Thomas, Christine

2015-12-01

The westernmost Mediterranean has developed into its present day tectonic configuration as a result of complex interactions between late stage subduction of the Neo-Tethys Ocean, continental collision of Africa and Eurasia, and the Canary Island mantle plume. This study utilizes S receiver functions (SRFs) from over 360 broadband seismic stations to seismically image the lithosphere and uppermost mantle from southern Spain through Morocco and the Canary Islands. The lithospheric thickness ranges from ∼65 km beneath the Atlas Mountains and the active volcanic islands to over ∼210 km beneath the cratonic lithosphere in southern Morocco. The common conversion point (CCP) volume of the SRFs indicates that thinned lithosphere extends from beneath the Canary Islands offshore southwestern Morocco, to beneath the continental lithosphere of the Atlas Mountains, and then thickens abruptly at the West African craton. Beneath thin lithosphere between the Canary hot spot and southern Spain, including below the Atlas Mountains and the Alboran Sea, there are distinct pockets of low velocity material, as inferred from high amplitude positive, sub-lithospheric conversions in the SRFs. These regions of low seismic velocity at the base of the lithosphere extend beneath the areas of Pliocene-Quaternary magmatism, which has been linked to a Canary hotspot source via geochemical signatures. However, we find that this volume of low velocity material is discontinuous along strike and occurs only in areas of recent volcanism and where asthenospheric mantle flow is identified with shear wave splitting analyses. We propose that the low velocity structure beneath the lithosphere is material flowing sub-horizontally northeastwards beneath Morocco from the tilted Canary Island plume, and the small, localized volcanoes are the result of small-scale upwellings from this material.

Seismic attenuation structure beneath Nazca Plate subduction zone in southern Peru

Science.gov (United States)

Jang, H.; Kim, Y.; Clayton, R. W.

2017-12-01

We estimate seismic attenuation in terms of quality factors, QP and QS using P and S phases, respectively, beneath Nazca Plate subduction zone between 10°S and 18.5°S latitude in southern Peru. We first relocate 298 earthquakes with magnitude ranges of 4.0-6.5 and depth ranges of 20-280 km. We measure t*, which is an integrated attenuation through the seismic raypath between the regional earthquakes and stations. The measured t* are inverted to construct three-dimensional attenuation structures of southern Peru. Checkerboard test results for both QP and QS structures ensure good resolution in the slab-dip transition zone between flat and normal slab subduction down to a depth of 200 km. Both QP and QS results show higher attenuation continued down to a depth of 50 km beneath volcanic arc and also beneath the Quimsachata volcano, the northernmost young volcano, located far east of the main volcanic front. We also observe high attenuation in mantle wedge especially beneath the normal subduction region in both QP and QS (100-130 in QP and 100-125 in QS) and slightly higher QP and QS beneath the flat-subduction and slab-dip transition regions. We plan to relate measured attenuation in the mantle wedge to material properties such as viscosity to understand the subduction zone dynamics.

The coexistence of Baird's tapir (Tapirus bairdii) and indigenous hunters in northeastern Honduras.

Science.gov (United States)

Dunn, Marc; Estrada, Nereyda; Smith, Derek A

2012-12-01

The Baird's tapir (Tapirus bairdii) is a popular game species throughout Central America, particularly among indigenous populations, and is currently endangered. Research on Miskitu hunting was conducted over 4 months in a remote region in northeastern Honduras that overlaps with the Río Plátano Biosphere Reserve. The hunting zone was mapped together with hunters and interviews were conducted with elders and other community members about tapir hunting. Results show that tapir harvesting is targeted toward specific habitats at specific times of year. Harvest rates for one year suggest that tapir hunting in the area exceeds estimates of maximum sustainable production. Nevertheless, field surveys reveal the presence of tapir within 1 km of the community, and its harvest tends to be nearby, in both forested and agricultural landscapes, suggesting that the animal has not been depleted in the area. It appears that the existence of forest areas adjacent to the hunting zone that do not experience hunting, together with the anthropogenic habitats created through shifting cultivation, are factors that help explain the presence of tapirs in the area. The article concludes with a discussion regarding the potential positive role of indigenous hunters in tapir conservation throughout its distribution range. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

Crustal Structure beneath Alaska from Receiver Functions

Science.gov (United States)

Zhang, Y.; Li, A.

2017-12-01

The crustal structure in Alaska has not been well resolved due to the remote nature of much of the state. The USArray Transportable Array (TA), which is operating in Alaska and northwestern Canada, significantly increases the coverage of broadband seismic stations in the region and allows for a more comprehensive study of the crust. We have analyzed P-receiver functions from earthquake data recorded by 76 stations of the TA and AK networks. Both common conversion point (CCP) and H-K methods are used to estimate the mean crustal thickness. The results from the CCP stacking method show that the Denali fault marks a sharp transition from thick crust in the south to thin crust in the north. The thickest crust up to 52 km is located in the St. Elias Range, which has been formed by oblique collision between the Yakutat microplate and North America. A thick crust of 48 km is also observed beneath the eastern Alaska Range. These observations suggest that high topography in Alaska is largely compensated by the thick crust root. The Moho depth ranges from 28 km to 35 km beneath the northern lowlands and increases to 40-45 km under the Books Range. The preliminary crustal thickness from the H-K method generally agrees with that from the CCP stacking with thicker crust beneath high mountain ranges and thinner crust beneath lowlands and basins. However, the offshore part is not well constrained due to the limited coverage of stations. The mean Vp/Vs ratio is around 1.7 in the Yukon-Tanana terrane and central-northern Alaska. The ratio is about 1.9 in central and southern Alaska with higher values at the Alaska Range, Wrangell Mountains, and St. Elias Range. Further data analyses are needed for obtaining more details of the crustal structure in Alaska to decipher the origin and development of different tectonic terranes.

Ancient DNA reveals lack of continuity between neolithic hunter-gatherers and contemporary Scandinavians

DEFF Research Database (Denmark)

Malmström, Helena; Gilbert, M Thomas P; Thomas, Mark G

2009-01-01

of the two cultures in Scandinavia has been cited as an argument against population replacement between the Mesolithic and the present [7, 8]. Through analysis of DNA extracted from ancient Scandinavian human remains, we show that people of the Pitted Ware culture were not the direct ancestors of modern......]. Furthermore, our data are consistent with the view that the eastern Baltic represents a genetic refugia for some of the European hunter-gatherer populations....

Deep long-period earthquakes beneath Washington and Oregon volcanoes

Science.gov (United States)

Nichols, M.L.; Malone, S.D.; Moran, S.C.; Thelen, W.A.; Vidale, J.E.

2011-01-01

Deep long-period (DLP) earthquakes are an enigmatic type of seismicity occurring near or beneath volcanoes. They are commonly associated with the presence of magma, and found in some cases to correlate with eruptive activity. To more thoroughly understand and characterize DLP occurrence near volcanoes in Washington and Oregon, we systematically searched the Pacific Northwest Seismic Network (PNSN) triggered earthquake catalog for DLPs occurring between 1980 (when PNSN began collecting digital data) and October 2009. Through our analysis we identified 60 DLPs beneath six Cascade volcanic centers. No DLPs were associated with volcanic activity, including the 1980-1986 and 2004-2008 eruptions at Mount St. Helens. More than half of the events occurred near Mount Baker, where the background flux of magmatic gases is greatest among Washington and Oregon volcanoes. The six volcanoes with DLPs (counts in parentheses) are Mount Baker (31), Glacier Peak (9), Mount Rainier (9), Mount St. Helens (9), Three Sisters (1), and Crater Lake (1). No DLPs were identified beneath Mount Adams, Mount Hood, Mount Jefferson, or Newberry Volcano, although (except at Hood) that may be due in part to poorer network coverage. In cases where the DLPs do not occur directly beneath the volcanic edifice, the locations coincide with large structural faults that extend into the deep crust. Our observations suggest the occurrence of DLPs in these areas could represent fluid and/or magma transport along pre-existing tectonic structures in the middle crust. ?? 2010 Elsevier B.V.

Big game hunting practices, meanings, motivations and constraints: a survey of Oregon big game hunters

Science.gov (United States)

Suresh K. Shrestha; Robert C. Burns

2012-01-01

We conducted a self-administered mail survey in September 2009 with randomly selected Oregon hunters who had purchased big game hunting licenses/tags for the 2008 hunting season. Survey questions explored hunting practices, the meanings of and motivations for big game hunting, the constraints to big game hunting participation, and the effects of age, years of hunting...

Petrological Constraints on Melt Generation Beneath the Asal Rift (Djibouti)

Science.gov (United States)

Pinzuti, P.; Humler, E.; Manighetti, I.; Gaudemer, Y.; Bézos, A.

2010-12-01

The temporal evolution of the mantle melting processes in the Asal Rift is evaluated from the chemical composition of 95 lava flows sampled along 10 km of the rift axis and 8 km off-axis (that is for the last 650 ky). The major element composition and the trace element ratios of aphyric basalts across the Asal Rift show a symmetric pattern relative to the rift axis and preserved a clear signal of mantle melting depth variations. FeO, Fe8.0, Sm/YbN and Zr/Y increase, whereas SiO2 and Lu/HfN decrease from the rift axis to the rift shoulders. These variations are qualitatively consistent with a shallower melting beneath the rift axis than off-axis and the data show that the melting regime is inconsistent with a passive upwelling model. In order to quantify the depth range and extent of melting, we invert Na8.0 and Fe8.0 contents of basalts based on a pure active upwelling model. Beneath the rift axis, melting paths are shallow, from 60 to 30 km. These melting paths are consistent with adiabatic melting in normal-temperature asthenosphere, beneath an extensively thinned mantle lithosphere. In contrast, melting on the rift shoulders occurred beneath a thick mantle lithosphere and required mantle solidus temperature 180°C hotter than normal (melting paths from 110 to 75 km). The calculated rate of lithospheric thinning is high (6.0 cm yr-1) and could explain the survival of a metastable garnet within the mantle at depth shallower than 90 km beneath the modern Asal Rift.

MRI findings in the mild type of mucopolysaccharidosis II (Hunter's syndrome)

International Nuclear Information System (INIS)

Shimoda-Matsubayashi, S.; Ito, T.; Hattori, N.; Okuma, Y.; Mizuno, Y.; Kuru, Y.; Sumie, H.

1990-01-01

Neuroradiological findings in a 44-year-old male with the typical mild type of Hunter's disease are reported. Cranial MRI revealed patchy areas of increased and decreased signals in T1- and T2-weighted images in the thalamus and the basal ganglia giving rise to a honey comb-like appearance as a whole. The deep white matter showed high signals in the T2-weighted image. To our knowledge, the honey comb-like appearance has never been reported in this disorder. Deposition of mucopolysaccharides and/or glycolipids and increase in fluid content seem to be responsible for these changes. (orig.)

Gender Segregation in Early-Childhood Social Play among the Bofi Foragers and Bofi Farmers in Central Africa

Science.gov (United States)

Fouts, Hillary N.; Hallam, Rena A.; Purandare, Swapna

2013-01-01

Gender segregation in early-childhood social play is a pervasive pattern in North America, and child-development scholars have suggested it is a human universal. But very few researchers have looked at gender segregation in small-scale societies, particularly those of hunter-gatherers, whom the authors here call foragers. The authors present their…

The extent of continental crust beneath the Seychelles

Science.gov (United States)

Hammond, J. O. S.; Kendall, J.-M.; Collier, J. S.; Rümpker, G.

2013-11-01

The granitic islands of the Seychelles Plateau have long been recognised to overlie continental crust, isolated from Madagascar and India during the formation of the Indian Ocean. However, to date the extent of continental crust beneath the Seychelles region remains unknown. This is particularly true beneath the Mascarene Basin between the Seychelles Plateau and Madagascar and beneath the Amirante Arc. Constraining the size and shape of the Seychelles continental fragment is needed for accurate plate reconstructions of the breakup of Gondwana and has implications for the processes of continental breakup in general. Here we present new estimates of crustal thickness and VP/VS from H-κ stacking of receiver functions from a year long deployment of seismic stations across the Seychelles covering the topographic plateau, the Amirante Ridge and the northern Mascarene Basin. These results, combined with gravity modelling of historical ship track data, confirm that continental crust is present beneath the Seychelles Plateau. This is ˜30-33 km thick, but with a relatively high velocity lower crustal layer. This layer thins southwards from ˜10 km to ˜1 km over a distance of ˜50 km, which is consistent with the Seychelles being at the edge of the Deccan plume prior to its separation from India. In contrast, the majority of the Seychelles Islands away from the topographic plateau show no direct evidence for continental crust. The exception to this is the island of Desroche on the northern Amirante Ridge, where thicker low density crust, consistent with a block of continental material is present. We suggest that the northern Amirantes are likely continental in nature and that small fragments of continental material are a common feature of plume affected continental breakup.

Hepatitis E virus antibody prevalence in hunters from a district in Central Germany, 2013: a cross-sectional study providing evidence for the benefit of protective gloves during disembowelling of wild boars.

Science.gov (United States)

Schielke, A; Ibrahim, V; Czogiel, I; Faber, M; Schrader, C; Dremsek, P; Ulrich, R G; Johne, R

2015-10-22

In Germany, 17% of the general human population have antibodies to hepatitis E virus (HEV) (recomLine HEV-IgG/IgM immunoassay [Mikrogen GmbH]). Wild boars represent an animal reservoir for HEV genotype 3, which is the common genotype in Germany. We estimated the seroprevalence among hunters with contact to wild boars to identify factors that may be associated with past or present HEV infection. In 2013, the local veterinarian authority in a district in Central Germany attended meetings of hunters who provided blood specimens and completed a questionnaire collecting information on age, sex, hunting-related activities and consumption of wild boar meat. Specimens of wild boars were taken during drive hunts in this district during the season 2012/2013. All specimens were tested for HEV RNA and anti-HEV IgM and IgG antibodies. Log-binomial regression was used to estimate prevalence ratios (PR) for the hunters. Of 126 hunters (median age 55; 94% male) 21% tested positive for anti-HEV IgG antibodies (95% confidence interval [CI] 13-28%) (recomWell HEV IgG assay [Mikrogen GmbH]). Anti-HEV prevalence was highest in the age group of the 70-79-year-olds (67%; 95% CI 39-95%). Wild boars showed an average anti-HEV prevalence of 41%. HEV RNA was detected in 4/22 (18%) liver specimens and in 1/22 (4.5%) muscle specimens. Most wild boars were tested positive for HEV RNA (3/10; 30%) and HEV-specific antibodies (7/15; 47%) in the southwestern part of the district. Hunters preferring this hunting ground had a lower anti-HEV prevalence when gloves were frequently used during disembowelling of wild boars compared to hunters using gloves never or infrequently (age-adjusted PR 0.12; 95% CI 0.02-0.86). Hunters may benefit from wearing gloves when in contact with blood or body fluids of HEV animal reservoirs. Anti-HEV prevalence among the hunters of this study did not significantly differ from that of the general population suggesting that other factors play a major role in the

Mapping magnetic lineaments and subsurface basement beneath ...

Indian Academy of Sciences (India)

65

studied the basement structures beneath parts of the Lower Benue Trough (LBT). Anudu et .... order vertical derivatives can be calculated respectively using the relations below: 145. ( ) ... minerals as in the case of the FVD-RTP-TMI (Figure 6).

S-wave attenuation structure beneath the northern Izu-Bonin arc

Science.gov (United States)

Takahashi, Tsutomu; Obana, Koichiro; Kodaira, Shuichi

2016-04-01

To understand temperature structure or magma distribution in the crust and uppermost mantle, it is essential to know their attenuation structure. This study estimated the 3-D S-wave attenuation structure in the crust and uppermost mantle at the northern Izu-Bonin arc, taking into account the apparent attenuation due to multiple forward scattering. In the uppermost mantle, two areas of high seismic attenuation (high Q -1) imaged beneath the volcanic front were mostly colocated with low-velocity anomalies. This coincidence suggests that these high- Q -1 areas in low-velocity zones are the most likely candidates for high-temperature regions beneath volcanoes. The distribution of random inhomogeneities indicated the presence of three anomalies beneath the volcanic front: Two were in high- Q -1 areas but the third was in a moderate- Q -1 area, indicating a low correlation between random inhomogeneities and Q -1. All three anomalies of random inhomogeneities were rich in short-wavelength spectra. The most probable interpretation of such spectra is the presence of volcanic rock, which would be related to accumulated magma intrusion during episodes of volcanic activity. Therefore, the different distributions of Q -1 and random inhomogeneities imply that the positions of hot regions in the uppermost mantle beneath this arc have changed temporally; therefore, they may provide important constraints on the evolutionary processes of arc crust and volcanoes.

The Catalyst Scholarship Program at Hunter College. A Partnership among Earth Science, Physics, Computer Science and Mathematics

Science.gov (United States)

Salmun, Haydee; Buonaiuto, Frank

2016-01-01

The Catalyst Scholarship Program at Hunter College of The City University of New York (CUNY) was established with a four-year award from the National Science Foundation (NSF) to fund scholarships to 40 academically talented but financially disadvantaged students majoring in four disciplines of science, technology, engineering and mathematics…

Morphological indicators of a mascon beneath Ceres' largest crater, Kerwan

Science.gov (United States)

Bland, Michael T.; Ermakov, Anton; Raymond, Carol A.; Williams, David A.; Bowling, Tim J.; Preusker, F.; Park, Ryan S.; Marchi, Simone; Castillo-Rogez, Julie C.; Fu, R.R.; Russell, Christopher T.

2018-01-01

Gravity data of Ceres returned by the National Aeronautics and Space Administration's Dawn spacecraft is consistent with a lower density crust of variable thickness overlying a higher density mantle. Crustal thickness variations can affect the long‐term, postimpact modification of impact craters on Ceres. Here we show that the unusual morphology of the 280 km diameter crater Kerwan may result from viscous relaxation in an outer layer that thins substantially beneath the crater floor. We propose that such a structure is consistent with either impact‐induced uplift of the high‐density mantle beneath the crater or from volatile loss during the impact event. In either case, the subsurface structure inferred from the crater morphology is superisostatic, and the mass excess would result in a positive Bouguer anomaly beneath the crater, consistent with the highest‐degree gravity data from Dawn. Ceres joins the Moon, Mars, and Mercury in having basin‐associated gravity anomalies, although their origin may differ substantially.

Morphological Indicators of a Mascon Beneath Ceres's Largest Crater, Kerwan

Science.gov (United States)

Bland, M. T.; Ermakov, A. I.; Raymond, C. A.; Williams, D. A.; Bowling, T. J.; Preusker, F.; Park, R. S.; Marchi, S.; Castillo-Rogez, J. C.; Fu, R. R.; Russell, C. T.

2018-02-01

Gravity data of Ceres returned by the National Aeronautics and Space Administration's Dawn spacecraft is consistent with a lower density crust of variable thickness overlying a higher density mantle. Crustal thickness variations can affect the long-term, postimpact modification of impact craters on Ceres. Here we show that the unusual morphology of the 280 km diameter crater Kerwan may result from viscous relaxation in an outer layer that thins substantially beneath the crater floor. We propose that such a structure is consistent with either impact-induced uplift of the high-density mantle beneath the crater or from volatile loss during the impact event. In either case, the subsurface structure inferred from the crater morphology is superisostatic, and the mass excess would result in a positive Bouguer anomaly beneath the crater, consistent with the highest-degree gravity data from Dawn. Ceres joins the Moon, Mars, and Mercury in having basin-associated gravity anomalies, although their origin may differ substantially.

Macrophysical climate models and Holocene hunter-gatherer subsistence shifts in Central Texas, USA

Science.gov (United States)

Mauldin, R. P.; Munoz, C.

2013-12-01

We use stable carbon isotopic values from bone collagen, as well as carbon values from carbonate extracted from bone apatite from 69 prehistoric human skeletal samples to investigate past resource use and climate relationships over the Middle and Late Holocene in Central Texas. Bone samples come from seven archaeological sites and samples date from 6,900 BP to the close of the prehistoric sequence at about 350 BP. Carbon isotopes from these samples suggest four broad dietary trends. From 6,900 through about 3,800 BP, carbon isotopes suggest a gradual increase in the consumption of resources that ultimately use a C3 photosynthetic pathway. A decline in δ13C in both collagen and carbonate values follows, suggesting a decrease in C3 resource use through roughly 2,900 BP. A variable, but once again increasing pattern on C3 resource use by prehistoric hunter-gatherers is indicated in bone isotopes through about 1,000 BP. After that date, a decrease in C3 resource dependence, with hints at greater subsistence diversity, is suggested through the close of the sequence at 350 BP. To assess the impact of climate shifts on this isotopic pattern, we developed a series of macrophysical climate models (MCM) for several locations in Central Texas focusing on fall, winter, and early spring precipitation. This fall-spring rainfall should closely determine C3 production. If subsistence shifts are responding to climate-induced changes in resource availability, then the measured hunter-gatherer carbon isotope trends summarized above should pattern with C3 production as monitored by the modeled fall-spring precipitation values. For the Middle Holocene portion of the sequence, the precipitation models suggest increasing C3 production, consistent with increasing C3 dependence shown in the isotopic data. A decline in C3 production between 3,900 and 3,000 BP in the models is also consistent with the isotopic decline at that point. After 3,000 BP, however, the coupling between fall

Thermally driven gas flow beneath Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Amter, S.; Lu, Ning; Ross, B.

1991-01-01

A coupled thermopneumatic model is developed for simulating heat transfer, rock-gas flow and carbon-14 travel time beneath Yucca Mountain, NV. The aim of this work is to understand the coupling of heat transfer and gas flow. Heat transfer in and near the potential repository region depends on several factors, including the geothermal gradient, climate, and local sources of heat such as radioactive wastes. Our numerical study shows that small temperature changes at the surface can change both the temperature field and the gas flow pattern beneath Yucca Mountain. A lateral temperature difference of 1 K is sufficient to create convection cells hundreds of meters in size. Differences in relative humidities between gas inside the mountain and air outside the mountain also significantly affect the gas flow field. 6 refs., 7 figs

Hunter-gatherer adaptations and environmental change in the southern Great Basin: The evidence from Pahute and Rainier mesas

Energy Technology Data Exchange (ETDEWEB)

Pippin, L.C.

1998-06-01

This paper reviews the evidence for fluctuations in past environments in the southern Great Basin and examines how these changes may have affected the strategies followed by past hunter and gatherers in their utilization of the resources available on a highland in this region. The evidence used to reconstruct past environments for the region include botanical remains from packrat middens, pollen spectra from lake and spring deposits, faunal remains recovered from archaeological and geologic contexts, tree-ring indices from trees located in sensitive (tree-line) environments, and eolian, alluvial and fluvial sediments deposited in a variety of contexts. Interpretations of past hunter and gatherer adaptive strategies are based on a sample of 1,311 archaeological sites recorded during preconstruction surveys on Pahute and Rainier mesas in advance of the US Department of Energy`s nuclear weapons testing program. Projectile point chronologies and available tree-ring, radiocarbon, thermoluminescence and obsidian hydration dates were used to assign these archaeological sites to specific periods of use.

Vessel guardians: sculpture and graphics related to the ceramics of NorthEastern European hunter-gatherers

Directory of Open Access Journals (Sweden)

Ekaterina Aleksandrovna Kashina

2015-12-01

Full Text Available North-Eastern European hunter-gatherer ceramic sculptures, relief sculptures and graphic images on vessels are discussed. Five groups of finds are distinguished according to their chronology (4000–2500 BC cal and represented subject (birds, human head, human figure, mammal head etc.. Their production believes to be a female craft, their making had ritual aims and their emerging was independent from any influences of pastoral/agricultural societies.

Analysis of groundwater flow beneath ice sheets

Energy Technology Data Exchange (ETDEWEB)

Boulton, G. S.; Zatsepin, S.; Maillot, B. [Univ. of Edinburgh (United Kingdom). Dept. of Geology and Geophysics

2001-03-01

The large-scale pattern of subglacial groundwater flow beneath European ice sheets was analysed in a previous report. It was based on a two-dimensional flowline model. In this report, the analysis is extended to three dimensions by exploring the interactions between groundwater and tunnel flow. A theory is developed which suggests that the large-scale geometry of the hydraulic system beneath an ice sheet is a coupled, self-organising system. In this system the pressure distribution along tunnels is a function of discharge derived from basal meltwater delivered to tunnels by groundwater flow, and the pressure along tunnels itself sets the base pressure which determines the geometry of catchments and flow towards the tunnel. The large-scale geometry of tunnel distribution is a product of the pattern of basal meltwater production and the transmissive properties of the bed. The tunnel discharge from the ice margin of the glacier, its seasonal fluctuation and the sedimentary characteristics of eskers are largely determined by the discharge of surface meltwater which penetrates to the bed in the terminal zone. The theory explains many of the characteristics of esker systems and can account for tunnel valleys. It is concluded that the large-scale hydraulic regime beneath ice sheets is largely a consequence of groundwater/tunnel flow interactions and that it is essential similar to non-glacial hydraulic regimes. Experimental data from an Icelandic glacier, which demonstrates measured relationships between subglacial tunnel flow and groundwater flow during the transition from summer to winter seasons for a modern glacier, and which support the general conclusions of the theory is summarised in an appendix.

Analysis of groundwater flow beneath ice sheets

International Nuclear Information System (INIS)

Boulton, G. S.; Zatsepin, S.; Maillot, B.

2001-03-01

The large-scale pattern of subglacial groundwater flow beneath European ice sheets was analysed in a previous report. It was based on a two-dimensional flowline model. In this report, the analysis is extended to three dimensions by exploring the interactions between groundwater and tunnel flow. A theory is developed which suggests that the large-scale geometry of the hydraulic system beneath an ice sheet is a coupled, self-organising system. In this system the pressure distribution along tunnels is a function of discharge derived from basal meltwater delivered to tunnels by groundwater flow, and the pressure along tunnels itself sets the base pressure which determines the geometry of catchments and flow towards the tunnel. The large-scale geometry of tunnel distribution is a product of the pattern of basal meltwater production and the transmissive properties of the bed. The tunnel discharge from the ice margin of the glacier, its seasonal fluctuation and the sedimentary characteristics of eskers are largely determined by the discharge of surface meltwater which penetrates to the bed in the terminal zone. The theory explains many of the characteristics of esker systems and can account for tunnel valleys. It is concluded that the large-scale hydraulic regime beneath ice sheets is largely a consequence of groundwater/tunnel flow interactions and that it is essential similar to non-glacial hydraulic regimes. Experimental data from an Icelandic glacier, which demonstrates measured relationships between subglacial tunnel flow and groundwater flow during the transition from summer to winter seasons for a modern glacier, and which support the general conclusions of the theory is summarised in an appendix

Ground-water quality beneath solid-waste disposal sites at anchorage, Alaska

Science.gov (United States)

Zenone, Chester; Donaldson, D.E.; Grunwaldt, J.J.

1975-01-01

Studies at three solid-waste disposal sites in the Anchorage area suggest that differences in local geohydrologic conditions influence ground-water quality. A leachate was detected in ground water within and beneath two sites where the water table is very near land surface and refuse is deposited either at or below the water table in some parts of the filled areas. No leachate was detected in ground water beneath a third site where waste disposal is well above the local water table.

Ancient DNA from hunter-gatherer and farmer groups from Northern Spain supports a random dispersion model for the Neolithic expansion into Europe.

Directory of Open Access Journals (Sweden)

Montserrat Hervella

Full Text Available BACKGROUND/PRINCIPAL FINDINGS: The phenomenon of Neolithisation refers to the transition of prehistoric populations from a hunter-gatherer to an agro-pastoralist lifestyle. Traditionally, the spread of an agro-pastoralist economy into Europe has been framed within a dichotomy based either on an acculturation phenomenon or on a demic diffusion. However, the nature and speed of this transition is a matter of continuing scientific debate in archaeology, anthropology, and human population genetics. In the present study, we have analyzed the mitochondrial DNA diversity in hunter-gatherers and first farmers from Northern Spain, in relation to the debate surrounding the phenomenon of Neolithisation in Europe. METHODOLOGY/SIGNIFICANCE: Analysis of mitochondrial DNA was carried out on 54 individuals from Upper Paleolithic and Early Neolithic, which were recovered from nine archaeological sites from Northern Spain (Basque Country, Navarre and Cantabria. In addition, to take all necessary precautions to avoid contamination, different authentication criteria were applied in this study, including: DNA quantification, cloning, duplication (51% of the samples and replication of the results (43% of the samples by two independent laboratories. Statistical and multivariate analyses of the mitochondrial variability suggest that the genetic influence of Neolithisation did not spread uniformly throughout Europe, producing heterogeneous genetic consequences in different geographical regions, rejecting the traditional models that explain the Neolithisation in Europe. CONCLUSION: The differences detected in the mitochondrial DNA lineages of Neolithic groups studied so far (including these ones of this study suggest different genetic impact of Neolithic in Central Europe, Mediterranean Europe and the Cantabrian fringe. The genetic data obtained in this study provide support for a random dispersion model for Neolithic farmers. This random dispersion had a different

Imaging magma plumbing beneath Askja volcano, Iceland

Science.gov (United States)

Greenfield, Tim; White, Robert S.

2015-04-01

Volcanoes during repose periods are not commonly monitored by dense instrumentation networks and so activity during periods of unrest is difficult to put in context. We have operated a dense seismic network of 3-component, broadband instruments around Askja, a large central volcano in the Northern Volcanic Zone, Iceland, since 2006. Askja last erupted in 1961, with a relatively small basaltic lava flow. Since 1975 the central caldera has been subsiding and there has been no indication of volcanic activity. Despite this, Askja has been one of the more seismically active volcanoes in Iceland. The majority of these events are due to an extensive geothermal area within the caldera and tectonically induced earthquakes to the northeast which are not related to the magma plumbing system. More intriguing are the less numerous deeper earthquakes at 12-24km depth, situated in three distinct areas within the volcanic system. These earthquakes often show a frequency content which is lower than the shallower activity, but they still show strong P and S wave arrivals indicative of brittle failure, despite their location being well below the brittle-ductile boundary, which, in Askja is ~7km bsl. These earthquakes indicate the presence of melt moving or degassing at depth while the volcano is not inflating, as only high strain rates or increased pore fluid pressures would cause brittle fracture in what is normally an aseismic region in the ductile zone. The lower frequency content must be the result of a slower source time function as earthquakes which are both high frequency and low frequency come from the same cluster, thereby discounting a highly attenuating lower crust. To image the plumbing system beneath Askja, local and regional earthquakes have been used as sources to solve for the velocity structure beneath the volcano. Travel-time tables were created using a finite difference technique and the residuals were used to solve simultaneously for both the earthquake locations

Environmental injustice and air pollution in coal affected communities, Hunter Valley, Australia

Energy Technology Data Exchange (ETDEWEB)

Higginbotham, N.; Freeman, S.; Connor, L.; Albrecht, G. [University of Newcastle, Callaghan, NSW (Australia). School of Medicine & Public Health

2010-03-15

The authors describe environmental injustice from air pollution in the Upper Hunter, Australia, and analyse the inaction of state authorities in addressing residents' health concerns. Obstacles blocking a public-requested health study and air monitoring include: the interdependence of state government and corporations in reaping the economic benefits of coal production; lack of political will, regulatory inertia and procedural injustice; and study design and measurement issues. We analyse mining- and coal-related air pollution in a contested socio-political arena, where residents, civil society and local government groups struggle with corporations and state government over the burden of imposed health risk caused by air pollution.

New constraints on the crustal structure beneath northern Tyrrhenian Sea

Science.gov (United States)

Levin, V. L.; Park, J. J.

2009-12-01

We present new seismological data on the seismic structure beneath the Tyrrhenian Sea between Corsica and the coast of Italy. Teleseismic receiver functions from two Tyrrhenian islands (Elba and Gorgona) identify clear P-to-S mode-converted waves from two distinct interfaces, at ~20 and ~45 km depth. Both interfaces are characterized by an increase of seismic wavespeed with depth. Using a summation of direct and multiply-reflected body waves within the P wave coda we estimate the mean ratio of compressional and shear wave speeds above the 45 km interface to be 1.75-1.80. Using reflectivity computations in 1D layered models we develop a model of seismic wavespeed distribution that yields synthetic seismograms very similar to those observed. We apply a Ps-multiple summation procedure to the synthetic waveforms to further verify the match between observed and predicted wavefields. The lower layer of our model, between 20 and 45 km, has Vp ~ 7.5 km/sec, a value that can be ascribed to either very fast crustal rocks or very slow upper mantle rocks. The Vp/Vs ratio is ~1.8 in this intermediate layer. On the basis of a well-constrained downward increase in seismic wave speed beneath this second layer, we interpret it as the magmatically reworked lower crust, a lithology that has been proposed to explain high-Vp layers in the crustal roots of island-arc terranes and volcanically altered continental margins, as well as lower-crustal high-Vp features sometimes seen beneath continental rifts. The presence of a thick layer of high-Vp, but crustal, lithology beneath the Tyrrhenian Sea differs considerably from previous estimates that interpreted the interface at ~20 km as the Moho. Our new interpretation obviates a need for a crustal thickness change of over 20 km at the crest of the Apennines orogen. We propose an alteration in the properties of the lower crust instead. We argue that ongoing convergent subduction of the Adriatic lithospehre is not required beneath northern

Period Determination of Asteroid Targets Observed at Hunters Hill Observatory: May 2009 - September 2010

Science.gov (United States)

Higgins, David

2011-01-01

Lightcurves for 27 asteroids were obtained at the Hunters Hill Observatory (HHO) from 2009 May through 2010 September: 308 Polyxo, 326 Tamara, 369 Aeria, 504 Cora, 822 Lalage, 1164 Kobolda, 1619 Ueta, 1625 The NORC, 1685 Toro, 2189 Zaragoza, 2287 Kalmykia, 2639 Planman, 3695 Fiaia, 4786 Tatianina, 5333 Kanaya, (5452) 1937 NN, 6170 Levasseur, 7741 Fedoseev, 14815 Rutberg, 15724 Zille, 16525 Shumarinaiko, (21996) 1993 XP31, (29729) 1999 BY1, (35404) 1997 YV5, (39087) 2000 VN50, (66146) 1998 TU3, and (101769) 1999 FF52.

Measured elemental transfer factors for boreal hunter/gatherer scenarios: fish, game and berries

International Nuclear Information System (INIS)

Sheppard, S.C.; Long, J.M.; Sanipelli, B.

2010-01-01

The environmental assessment of long-term nuclear waste management requires data to estimate food chain transfers for radionuclides in various environmental settings. For key elements such as iodine (I) and chlorine (Cl), there is a paucity of transfer factor data, particularly outside of agricultural food chains. This study dealt with transfers of I, Cl and 28 other elements to foods that would be typical of boreal hunter/gatherer lifestyles, as well as being common foods for modern recreational and subsistence hunters. Food/substrate concentration ratios (CRs) and related transfer factors for eight species of widely distributed fish, whitetail deer (Odocoileus virginianus), Canada geese (Branta canadensis) and wild blueberries (Vaccinium myrtilloides) were measured and compared to the literature. Limited data were obtained for caribou (Rangifer tarandus), elk (Cervus elaphus) and moose (Alces americanus). Freshwater sediment Kd values and CRs for a ubiquitous freshwater macrophyte were also obtained. The CRs for I in fish were 29 L kg -1 in edible muscle (fillets) of large-bodied species and 85 L kg -1 for whole, small-bodied fish. The log CRs for fish and macrophytes were correlated across elements. For several elements, the Kds for sediments in deep water were ∼4-fold higher than for littoral samples. The elemental transfers to wild animals for some elements were notably different than the literature indicates for domestic animals. It is argued that the transfer data obtained using indigenous elements from real environmental settings, as opposed to contaminant elements in experimental or impacted environments, are especially relevant to assessment of long-term impacts.

Measured elemental transfer factors for boreal hunter/gatherer scenarios: fish, game and berries

Energy Technology Data Exchange (ETDEWEB)

Sheppard, S.C., E-mail: sheppards@ecomatters.co [ECOMatters Inc., WB Lewis Business Centre, 24 Aberdeen Avenue, Pinawa, Manitoba R0E 1L0 (Canada); Long, J.M.; Sanipelli, B. [ECOMatters Inc., WB Lewis Business Centre, 24 Aberdeen Avenue, Pinawa, Manitoba R0E 1L0 (Canada)

2010-11-15

The environmental assessment of long-term nuclear waste management requires data to estimate food chain transfers for radionuclides in various environmental settings. For key elements such as iodine (I) and chlorine (Cl), there is a paucity of transfer factor data, particularly outside of agricultural food chains. This study dealt with transfers of I, Cl and 28 other elements to foods that would be typical of boreal hunter/gatherer lifestyles, as well as being common foods for modern recreational and subsistence hunters. Food/substrate concentration ratios (CRs) and related transfer factors for eight species of widely distributed fish, whitetail deer (Odocoileus virginianus), Canada geese (Branta canadensis) and wild blueberries (Vaccinium myrtilloides) were measured and compared to the literature. Limited data were obtained for caribou (Rangifer tarandus), elk (Cervus elaphus) and moose (Alces americanus). Freshwater sediment Kd values and CRs for a ubiquitous freshwater macrophyte were also obtained. The CRs for I in fish were 29 L kg{sup -1} in edible muscle (fillets) of large-bodied species and 85 L kg{sup -1} for whole, small-bodied fish. The log CRs for fish and macrophytes were correlated across elements. For several elements, the Kds for sediments in deep water were {approx}4-fold higher than for littoral samples. The elemental transfers to wild animals for some elements were notably different than the literature indicates for domestic animals. It is argued that the transfer data obtained using indigenous elements from real environmental settings, as opposed to contaminant elements in experimental or impacted environments, are especially relevant to assessment of long-term impacts.

Ancient Continental Lithosphere Dislocated Beneath Ocean Basins Along the Mid-Lithosphere Discontinuity: A Hypothesis

Science.gov (United States)

Wang, Zhensheng; Kusky, Timothy M.; Capitanio, Fabio A.

2017-09-01

The documented occurrence of ancient continental cratonic roots beneath several oceanic basins remains poorly explained by the plate tectonic paradigm. These roots are found beneath some ocean-continent boundaries, on the trailing sides of some continents, extending for hundreds of kilometers or farther into oceanic basins. We postulate that these cratonic roots were left behind during plate motion, by differential shearing along the seismically imaged mid-lithosphere discontinuity (MLD), and then emplaced beneath the ocean-continent boundary. Here we use numerical models of cratons with realistic crustal rheologies drifting at observed plate velocities to support the idea that the mid-lithosphere weak layer fostered the decoupling and offset of the African continent's buoyant cratonic root, which was left behind during Meso-Cenozoic continental drift and emplaced beneath the Atlantic Ocean. We show that in some cratonic areas, the MLD plays a similar role as the lithosphere-asthenosphere boundary for accommodating lateral plate tectonic displacements.

Slow Earthquake Hunters: A New Citizen Science Project to Identify and Catalog Slow Slip Events in Geodetic Data

Science.gov (United States)

Bartlow, N. M.

2017-12-01

Slow Earthquake Hunters is a new citizen science project to detect, catalog, and monitor slow slip events. Slow slip events, also called "slow earthquakes", occur when faults slip too slowly to generate significant seismic radiation. They typically take between a few days and over a year to occur, and are most often found on subduction zone plate interfaces. While not dangerous in and of themselves, recent evidence suggests that monitoring slow slip events is important for earthquake hazards, as slow slip events have been known to trigger damaging "regular" earthquakes. Slow slip events, because they do not radiate seismically, are detected with a variety of methods, most commonly continuous geodetic Global Positioning System (GPS) stations. There is now a wealth of GPS data in some regions that experience slow slip events, but a reliable automated method to detect them in GPS data remains elusive. This project aims to recruit human users to view GPS time series data, with some post-processing to highlight slow slip signals, and flag slow slip events for further analysis by the scientific team. Slow Earthquake Hunters will begin with data from the Cascadia subduction zone, where geodetically detectable slow slip events with a duration of at least a few days recur at regular intervals. The project will then expand to other areas with slow slip events or other transient geodetic signals, including other subduction zones, and areas with strike-slip faults. This project has not yet rolled out to the public, and is in a beta testing phase. This presentation will show results from an initial pilot group of student participants at the University of Missouri, and solicit feedback for the future of Slow Earthquake Hunters.

Ancient lipids document continuity in the use of early hunter-gatherer pottery through 9,000 years of Japanese prehistory.

Science.gov (United States)

Lucquin, Alexandre; Gibbs, Kevin; Uchiyama, Junzo; Saul, Hayley; Ajimoto, Mayumi; Eley, Yvette; Radini, Anita; Heron, Carl P; Shoda, Shinya; Nishida, Yastami; Lundy, Jasmine; Jordan, Peter; Isaksson, Sven; Craig, Oliver E

2016-04-12

The earliest pots in the world are from East Asia and date to the Late Pleistocene. However, ceramic vessels were only produced in large numbers during the warmer and more stable climatic conditions of the Holocene. It has long been assumed that the expansion of pottery was linked with increased sedentism and exploitation of new resources that became available with the ameliorated climate, but this hypothesis has never been tested. Through chemical analysis of their contents, we herein investigate the use of pottery across an exceptionally long 9,000-y sequence from the Jōmon site of Torihama in western Japan, intermittently occupied from the Late Pleistocene to the mid-Holocene. Molecular and isotopic analyses of lipids from 143 vessels provides clear evidence that pottery across this sequence was predominantly used for cooking marine and freshwater resources, with evidence for diversification in the range of aquatic products processed during the Holocene. Conversely, there is little indication that ruminant animals or plants were processed in pottery, although it is evident from the faunal and macrobotanical remains that these foods were heavily exploited. Supported by other residue analysis data from Japan, our results show that the link between pottery and fishing was established in the Late Paleolithic and lasted well into the Holocene, despite environmental and socio-economic change. Cooking aquatic products in pottery represents an enduring social aspect of East Asian hunter-gatherers, a tradition based on a dependable technology for exploiting a sustainable resource in an uncertain and changing world.

Preferences for symmetry in human faces in two cultures: data from the UK and the Hadza, an isolated group of hunter-gatherers.

Science.gov (United States)

Little, Anthony C; Apicella, Coren L; Marlowe, Frank W

2007-12-22

Many studies show agreement within and between cultures for general judgements of facial attractiveness. Few studies, however, have examined the attractiveness of specific traits and few have examined preferences in hunter-gatherers. The current study examined preferences for symmetry in both the UK and the Hadza, a hunter-gatherer society of Tanzania. We found that symmetry was more attractive than asymmetry across both the cultures and was more strongly preferred by the Hadza than in the UK. The different ecological conditions may play a role in generating this difference. Such variation in preference may be adaptive if it reflects adaptation to local conditions. Symmetry is thought to indicate genetic quality, which may be more important among the Hadza with much higher mortality rates from birth onwards. Hadza men who were more often named as good hunters placed a greater value on symmetry in female faces. These results suggest that high quality Hadza men are more discriminating in their choice of faces. Hadza women had increased preferences for symmetry in men's faces when they were pregnant or nursing, perhaps due to their increased discrimination and sensitivity to foods and disease harmful to a foetus or nursing infant. These results imply that symmetry is an evolutionarily relevant trait and that variation in symmetry preference appears strategic both between cultures and within individuals of a single culture.

Improvements to the Hunter Dose tracking system

Energy Technology Data Exchange (ETDEWEB)

Whiteside, T. S. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Aucott, T. J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Brand, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Diprete, D. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-07-01

Since 1965, the Savannah River Site (SRS) has conducted deer hunts which are open to the general public. SRS performs field monitoring for cesium-137 (Cs-137) of each harvested animal to determine whether the animal may be released to the hunter. A new field system for measuring Cs-137 in the harvested animals has been developed. The system incorporates numerous enhancements compared to the original system. The original system was composed of two Ludlum Measurements scalar-driven 2 inch x 2 inch sodium iodide counters, while the new system is based on a single Ametek Ortec Digibase-driven 2 inch x 4 inch x 16 inch sodium iodide gamma spectrometer. The new system includes a series of easy-to-assemble stainless steel encapsulated lead shields. The combination of the larger detector size and lead shielding improved the detection limit of the new system by a factor of approximately three compared to the original system. This lower detection limit allows for a larger number of measurements to be directly compared to the laboratory results, in cases where animal portions have been sampled. The results from developing and using this system are presented as well as recommendations on improvements to the overall field monitoring of the SRS hunts.

Hydrogeologic characteristics and water quality of a confined sand unit in the surficial aquifer system, Hunter Army Airfield, Chatham County, Georgia

Science.gov (United States)

Gonthier, Gerard

2012-01-01

An 80-foot-deep well (36Q397, U.S. Geological Survey site identification 320146081073701) was constructed at Hunter Army Airfield to assess the potential of using the surficial aquifer system as a water source to irrigate a ballfield complex. A 300-foot-deep test hole was drilled beneath the ballfield complex to characterize the lithology and water-bearing characteristics of sediments above the Upper Floridan aquifer. The test hole was then completed as well 36Q397 open to a 19-foot-thick shallow, confined sand unit contained within the surficial aquifer system. A single-well, 24-hour aquifer test was performed by pumping well 36Q397 at a rate of 50 gallons per minute during July 13-14, 2011, to characterize the hydrologic properties of the shallow, confined sand unit. Two pumping events prior to the aquifer test affected water levels. Drawdown during all three pumping events and residual drawdown during recovery periods were simulated using the Theis formula on multiple changes in discharge rate. Simulated drawdown and residual drawdown match well with measured drawdown and residual drawdown using values of horizontal hydraulic conductivity and specific storage, which are typical for a confined sand aquifer. Based on the hydrologic parameters used to match simulated drawdown and residual drawdown to measured drawdown and residual drawdown, the transmissivity of the sand was determined to be about 400 feet squared per day. The horizontal hydraulic conductivity of the sand was determined to be about 20 feet per day. Analysis of a water-quality sample indicated that the water is suitable for irrigation. Sample analysis indicated a calcium-carbonate type water having a total dissolved solids concentration of 39 milligrams per liter. Specific conductance and concentrations of all analyzed constituents were below those that would be a concern for irrigation, and were below primary and secondary water-quality criteria levels.

Triassic rejuvenation of unexposed Archean-Paleoproterozoic deep crust beneath the western Cathaysia block, South China

Science.gov (United States)

Li, Xi-Yao; Zheng, Jian-Ping; Xiong, Qing; Zhou, Xiang; Xiang, Lu

2018-01-01

Jurassic (ca. 150 Ma) Daoxian basalts from the western Cathaysia block (South China) entrained a suite of deep-seated crustal xenoliths, including felsic schist, gneiss and granulite, and mafic two-pyroxene granulite and metagabbro. Zircon U-Pb-Hf isotopic, whole-rock elemental and Sr-Nd-Pb isotopic compositions have been determined for these valuable xenoliths to reveal the poorly-known, unexposed deep crust beneath South China. Detrital zircons from the garnet-biotite schists show several populations of ages at 0.65-0.5 Ga, 1.1-0.75 Ga, 1.6-1.4 Ga, 1.8-1.7 Ga, 2.5-2.4 Ga, 2.8 Ga, and 3.5 Ga, representing a multi-sourced, meta-sedimentary origin with deposition time at the early Cambrian. One mafic granulite contains zircons with concordant U-Pb ages of Neoarchean ( 2520 Ma), as well as Hf model ages of 2.8-2.6 Ga and positive εHf(t) values (up to 6.3), suggesting an accretion of juvenile crust in Neoarchean, probably as the main framework of the lower crust. Geochemical and geochronological evidence shows the mafic granulite and metagabbro were produced by underplating of magmas derived from the depleted asthenosphere and mixed with EM2-type materials during the Late Triassic (205-196 Ma). This magmatic underplating also resulted in the widespread metamorphism of the mafic lower crust and felsic middle crust (e.g., the felsic granulite and gneiss) at 202-201 Ma. We suggest the existence of a highly evolved Archean-Paleoproterozoic basement beneath the western Cathaysia block, which experienced episodic accretion and reworking and the strong rejuvenation during the Triassic. A three-layered structure of the lower crust could exist beneath the Daoxian area during the Jurassic time: its upper layer is an evolved Archean-Paleoproterozoic basement; the middle hybrid layer represents a mixture of Archean-Paleoproterozoic basement with newly accreted/reworked Proterozoic to Phanerozoic materials; and the deeper layer consists of mafic granulites derived from the

General medicine advanced training: lessons from the John Hunter training programme.

Science.gov (United States)

Jackel, D; Attia, J; Pickles, R

2014-03-01

Recent years have seen a rapid growth in the number of advanced trainees pursuing general medicine as a specialty. This reflects an awareness of the need for broader training experiences to equip future consultant physicians with the skills to manage the healthcare challenges arising from the demographic trends of ageing and increasing comorbidity. The John Hunter Hospital training programme in general medicine has several characteristics that have led to the success in producing general physicians prepared for these challenges. These include support from a core group of committed general physicians, an appropriate and sustainable funding model, flexibility with a focus on genuine training and developing awareness of a systems approach, and strong links with rural practice. © 2014 The Authors; Internal Medicine Journal © 2014 Royal Australasian College of Physicians.

Síndrome de Hunter-Hurler

Directory of Open Access Journals (Sweden)

Antonio B. Lefèvre

1954-03-01

Full Text Available Les deux cas de gargoylisme présentés ont appelé l'attention des auteurs et ont mérité leur publication vue la rareté de la maladie en question. Le diagnostic repose en un certain nombre de signes cliniques, lesquels, cependant, n'ont pas besoin d'être au complet pour que l'on puisse affermir le diagnostic du syndrome de Hunter-Hurler. C'est ce qui arrive, d'ailleurs, avec la majorité des maladies de caractère génétique, dans les-quelles il est possible de verifier la transmission de quelques traits seule-ment de Pensemble clinique, insuffisants pour caractériser la maladie sous tous ses aspects, mais suffisants pour permettre un diagnostic très sûr. Cas nº 1: les auteurs font ressortir la face caractéristique de la maladie, la petite taille, les doigts en griffe, les alterations très caractéristiques de forme des vertèbres lombaires et le retard psycho-moteur considérable; comme antécédents familiaux, il a été constaté qu'une cousine-germaine du côté paternel de la malade est morte à 1'âge de 12 ans d'une maladie semblable. Cas nº 2: ici ressortent la face caractéristique, la petite taille, le développement retardé, les altérations des vertèbres lombaires et, à l'examen oculaire, un aspect suggestif de l'opacité cornéenne considérée comme pathognomonique du gargoylisme. Aucun traitement a été tenté dans les deux cas.

Imaging voids beneath bridge bent using electrical resistivity tomography.

Science.gov (United States)

2014-02-01

Five electrical resistivity tomography (ERT) profiles and borehole control were acquired beneath two bridges on the bank of the : Gasconade River in order to determine extension of the underground water-filled openings in rock encountered during a dr...

Factors impacting hunter access to private lands in southeast Minnesota

Science.gov (United States)

Walberg, Eric; Cornicelli, Louis; Fulton, David C.

2018-01-01

White-tailed deer (Odocoileus virginianus) have important socioeconomic and ecological impacts in the United States. Hunting is considered to be important for the effective management of deer and relies on access to privately owned lands. In 2013, we surveyed nonindustrial private landowners in southeast Minnesota and created two logit models to examine factors that impact landowners’ decision to (a) allow public hunting access and (b) post private property. Parcel characteristics were found to impact landowner decisions to allow hunting access, particularly the size of the property and whether it was posted. Hunting access to small properties was more likely to be restricted to family, friends, and neighbors (83%) compared to medium (74%) or large properties (60%). Hunter concerns (e.g., liability) and knowledge about deer management was significant in both models, suggesting there are opportunities to educate landowners about the importance of allowing public hunting access and available liability protections.

Balinese Y-chromosome perspective on the peopling of Indonesia: genetic contributions from pre-neolithic hunter-gatherers, Austronesian farmers, and Indian traders.

Science.gov (United States)

Karafet, Tatiana M; Lansing, J S; Redd, Alan J; Reznikova, Svetlana; Watkins, Joseph C; Surata, S P K; Arthawiguna, W A; Mayer, Laura; Bamshad, Michael; Jorde, Lynn B; Hammer, Michael F

2005-02-01

The island of Bali lies near the center of the southern chain of islands in the Indonesian archipelago, which served as a stepping-stone for early migrations of hunter-gatherers to Melanesia and Australia and for more recent migrations of Austronesian farmers from mainland Southeast Asia to the Pacific. Bali is the only Indonesian island with a population that currently practices the Hindu religion and preserves various other Indian cultural, linguistic, and artistic traditions (Lansing 1983). Here, we examine genetic variation on the Y chromosomes of 551 Balinese men to investigate the relative contributions of Austronesian farmers and pre-Neolithic hunter-gatherers to the contemporary Balinese paternal gene pool and to test the hypothesis of recent paternal gene flow from the Indian subcontinent. Seventy-one Y-chromosome binary polymorphisms (single nucleotide polymorphisms, SNPs) and 10 Y-chromosome-linked short tandem repeats (STRs) were genotyped on a sample of 1,989 Y chromosomes from 20 populations representing Indonesia (including Bali), southern China, Southeast Asia, South Asia, the Near East, and Oceania. SNP genotyping revealed 22 Balinese lineages, 3 of which (O-M95, O-M119, and O-M122) account for nearly 83.7% of Balinese Y chromosomes. Phylogeographic analyses suggest that all three major Y-chromosome haplogroups migrated to Bali with the arrival of Austronesian speakers; however, STR diversity patterns associated with these haplogroups are complex and may be explained by multiple waves of Austronesian expansion to Indonesia by different routes. Approximately 2.2% of contemporary Balinese Y chromosomes (i.e., K-M9*, K-M230, and M lineages) may represent the pre-Neolithic component of the Indonesian paternal gene pool. In contrast, eight other haplogroups (e.g., within H, J, L, and R), making up approximately 12% of the Balinese paternal gene pool, appear to have migrated to Bali from India. These results indicate that the Austronesian expansion had a

Pavlovian hunters on the margin - archaeozoological analysis of the animal remains discovered at the Pavlov II site (1966-67 excavations)

Czech Academy of Sciences Publication Activity Database

Wilczyński, J.; Wojtal, P.; Svoboda, Jiří

2017-01-01

Roč. 73, 3-4 (2017), s. 322-331 ISSN 2533-4050 Institutional support: RVO:68081758 Keywords : Gravettian * hunters-gatherers * southern Moravia * subsistence strategies Subject RIV: AC - Archeology, Anthropology, Ethnology OBOR OECD: Archaeology http://fi.nm.cz/wp-content/uploads/2017/12/06_Wilczynski_et-al_2017.pdf

A Bed-Deformation Experiment Beneath Engabreen, Norway

Science.gov (United States)

Iverson, N. R.; Hooyer, T. S.; Fischer, U. H.; Cohen, D.; Jackson, M.; Moore, P. L.; Lappegard, G.; Kohler, J.

2001-12-01

Although deformation of sediment beneath ice masses may contribute to their motion and may sometimes enable fast glacier flow, both the kinematics and mechanics of deformation are controversial. This controversy stems, in part, from subglacial measurements that are difficult to interpret. Measurements have been made either beneath ice margins or remotely through boreholes with interpretive limitations caused by uncertain instrument position and performance, uncertain sediment thickness and bed geometry, and unknown disturbance of the bed and stress state by drilling. We have used a different approach made possible by the Svartisen Subglacial Laboratory, which enables human access to the bed of Engabreen, Norway, beneath 230 m of temperate ice. A trough (2 m x 1.5 m x 0.4 m deep) was blasted in the rock bed and filled with sediment (75 percent sand and gravel, 20 percent silt, 5 percent clay). Instruments were placed in the sediment to record shear deformation (tiltmeters), dilation and contraction, total normal stress, and pore-water pressure. Pore pressure was manipulated by feeding water to the base of the sediment with a high-pressure pump, operated in a rock tunnel 4 m below the bed surface. After irregular deformation during closure of ice on the sediment, shear deformation and volume change stopped, and total normal stress became constant at 2.2 MPa. Subsequent pump tests, which lasted several hours, induced pore-water pressures greater than 70 percent of the total normal stress and resulted in shear deformation over most of the sediment thickness with attendant dilation. Ice separated from the sediment when effective normal stress was lowest, arresting shear deformation. Displacement profiles during pump tests were similar to those observed by Boulton and co-workers at Breidamerkurjökull, Iceland, with rates of shear strain increasing upward toward the glacier sole. Such deformation does not require viscous deformation resistance and is expected in a

Hunter color dimensions, sugar content and volatile compounds in pasteurized yellow passion fruit juice (Passiflora edulis var. flavicarpa during storage

Directory of Open Access Journals (Sweden)

Delcio Sandi

2004-06-01

Full Text Available Changes in Hunter L, a and b values, glucose, fructose and sucrose contents, concentration of four volatile compounds (ethyl butirate, ethyl caproate, hexyl butirate and hexyl caproate and furfural, were studied in yellow passion fruit juice (Passiflora edulis var. flavicarpa pasteurized at 75ºC/60s, 80ºC/41s or 85ºC/27s, during storage at room temperature (25±5ºC and refrigeration (5±1ºC for 120 days. While the sucrose content decreased, the glucose and fructose contents increased significantly over storage time. The Hunter L and b values behaved similarly, with a tendency to decrease over time, inversely to Hunter a value. Volatile compound concentrations also decreased over time, inversely to the furfural content. Pasteurization at 85ºC/27s resulted minimum changes in the studied passion fruit characteristics, while that at 75ºC/60s was the most harmful. Storage under refrigeration tended to keep the best quality characteristics of the juice.Foi estudada a variação dos valores "L", "a" e "b" do sistema de Hunter, dos teores de glucose, frutose e sacarose, e da concentração de quatro compostos voláteis (butirato de etila, caproato de etila, butirato de hexila e caproato de hexila e furfural, em suco de maracujá-amarelo (Passiflora edulis var. flavicarpa submetido à pasteurização (75ºC/60 s, 80ºC/41 s e 85ºC/27 s, durante o armazenamento a temperatura ambiente (25±5ºC e refrigerada (5±1ºC por 120 dias. Enquanto os teores de sacarose diminuíram, aqueles de glucose e frutose aumentaram significativamente. Os valores "L" e "b" apresentaram comportamento semelhante, com tendência a diminuir ao longo do tempo, inversamente ao valor "a". As concentrações dos compostos voláteis também diminuíram, exceto para o furfural. A pasteurização a 85ºC/27 s proporcionou as menores alterações nas características estudadas, enquanto aquela à 75ºC/60 s foi a mais prejudicial. O armazenamento sob refrigeração apresentou

Lead shot pellets dispersed by hunters: ingested by ducks

Energy Technology Data Exchange (ETDEWEB)

Danell, K [Univ. of Umea, Sweden; Andersson, A; Marcstrom, V

1977-01-01

Many of the lead pellets shot by waterfowl hunters over shores and waters fall on the feeding grounds of ducks and geese. These pellets, picked up and ingested by the birds, can remain in the gizzard where they are eroded by mechanical and chemical action. In some cases the bird absorbs enough lead to cause lead poisoning. This report describes the incidence of ingested lead shot pellets found in 928 ducks collected in Sweden during hunting season. Pellets were found in both dabbling and diving ducks and were present in birds from six of the eight localities sampled. Usually one or two pellets were found but some ducks contained up to 62 pellets. As the incidence of ingested pellets in the present study is approximately the same as that found in North America, where the annual duck loss due to lead poisoning is estimated to be 2 to 3 percent of the population, it may be assumed that lead poisoning is a mortality factor for Swedish ducks also.

Buckling instabilities of subducted lithosphere beneath the transition zone

NARCIS (Netherlands)

Ribe, N.M.; Stutzmann, E.; Ren, Y.; Hilst, R.D. van der

2007-01-01

A sheet of viscous fluid poured onto a surface buckles periodically to generate a pile of regular folds. Recent tomographic images beneath subduction zones, together with quantitative fluid mechanical scaling laws, suggest that a similar instability can occur when slabs of subducted oceanic

An Analysis on Langston Hughes’ Writing Technique——plotlessness in Early Autumn

Institute of Scientific and Technical Information of China (English)

娄佳丽

2014-01-01

Langston Hughes shows a different writing technique in his short story Early Autumn.He uses plotlessness, an irregular narrative technique, to reflect the character’s emotional undercurrents beneath the calm surface and also forms a sharp contrast with the character’s intense emotional change.

Soil microbial respiration beneath Stipa tenacissima L. and in surrounding bare soil

Directory of Open Access Journals (Sweden)

Irena Novosádová

2011-01-01

Full Text Available Open steppes dominated by Stipa tenacissima L. constitute one of the most representative ecosystems of the semi-arid zones of Eastern Mediterranean Basin (Iberian Peninsula, North of Africa. Ecosystem functioning of these steppes is strongly related to the spatial pattern of grass tussocks. Soils beneath Stipa tenacissima L. grass show different fertility and different microclimatic conditions than in surrounding bare soil. The objective of this study was to assess the effect of Stipa tenacissima L. on the key soil microbial activities under controlled incubation conditions (basal and potential respiration. Basal and potential microbial respirations in the soils beneath Stipa tenacissima L. were, in general, not significantly different from the bare soils. The differences were less than 10%. Significantly less ethylene produced by microbial activity in soils beneath Stipa tenacissima L. after the addition of glucose could indicate the dependence of rhizospheric microbial communities on available carbon compounds. It can be concluded, that the soil respiration in semi-arid Mediterranean ecosystems is not necessarily associated with the patchy plant distribution and that some microbial activities characteristics can be unexpectedly homogenous.

Tomography of the upper mantle beneath the African/Iberian collision zone

Science.gov (United States)

Mickael, B.; Nolet, G.; Villasenor, A.; Josep, G.; Thomas, C.

2013-12-01

During Cenozoic, geodynamics of the western Mediterranean domain has been characterized by a complex history of subduction of Mesozoic oceanic lithosphere. The final stage of these processes is proposed to have led to the development of the Calabria and Gibraltar arcs, whose formation is still under debate. In this study we take advantage of the dense broadband-station networks now available in Alborán Sea region, to develop a high-resolution 3D tomographic P velocity model of the upper mantle beneath the African/Iberian collision zone that will bring new constraints on the past dynamics of this zone. The model is based on 13200 teleseismic arrival times recorded between 2008 and 2012 at 279 stations for which cross-correlation delays are measured with a new technique in different frequency bands centered between 0.03 and 1.0 Hz, and interpreted using multiple frequency tomography. Our model shows, beneath Alborán Sea, a strong (~ 4%) fast vertically dipping anomaly observed to at least 650 km depth. The arched shape of this anomaly and its extent at depth are coherent with a lithospheric slab, thus favoring the hypothesis of a westward consumption of the Ligurian ocean slab by roll-back during Cenozoic. In addition to this fast anomaly in the deep upper-mantle, several high intensity slow anomalies are widely observed in the lithosphere and asthenosphere beneath Morocco and southern Spain. These anomalies are correlated at surface with the position of the orogens (Rif and Atlas) and with Cenozoic volcanic fields. We thus confirm the presence, beneath Morocco, of an anomalous (hot) upper mantle, with piece of evidence for a lateral connection with the Canary volcanic islands, likely indicating a lateral spreading of the Canary plume to the east.

Nutrient transport and transformation beneath an infiltration basin

Science.gov (United States)

Sumner, D.M.; Rolston, D.E.; Bradner, L.A.

1998-01-01

Field experiments were conducted to examine nutrient transport and transformation beneath an infiltration basin used for the disposal of treated wastewater. Removal of nitrogen from infiltrating water by denitrification was negligible beneath the basin, probably because of subsurface aeration as a result of daily interruptions in basin loading. Retention of organic nitrogen in the upper 4.6 m of the unsaturated zone (water table depth of approximately 11 m) during basin loading resulted in concentrations of nitrate as much as 10 times that of the applied treated wastewater, following basin 'rest' periods of several weeks, which allowed time for mineralization and nitrification. Approximately 90% of the phosphorus in treated wastewater was removed within the upper 4.6 m of the subsurface, primarily by adsorption reactions, with abundant iron and aluminum oxyhydroxides occurring as soil coatings. A reduction in the flow rate of infiltrating water arriving at the water table may explain the accumulation of relatively coarse (>0.45 ??m), organic forms of nitrogen and phosphorus slightly below the water table. Mineralization and nitrification reactions at this second location of organic nitrogen accumulation contributed to concentrations of nitrate as much as three times that of the applied treated wastewater. Phosphorus, which accumulated below the water table, was immobilized by adsorption or precipitation reactions during basin rest periods.Field experiments were conducted to examine nutrient transport and transformation beneath an infiltration basin used for the disposal of treated wastewater. Removal of nitrogen from infiltrating water by denitrification was negligible beneath the basin, probably because of subsurface aeration as a result of daily interruptions in basin loading. Retention of organic nitrogen in the upper 4.6 m of the unsaturated zone (water table depth of approximately 11 m) during basin loading resulted in concentrations of nitrate as much as 10

Evolution of deep crustal magma structures beneath Mount Baekdu volcano (MBV) intraplate volcano in northeast Asia

Science.gov (United States)

Rhie, J.; Kim, S.; Tkalcic, H.; Baag, S. Y.

2017-12-01

Heterogeneous features of magmatic structures beneath intraplate volcanoes are attributed to interactions between the ascending magma and lithospheric structures. Here, we investigate the evolution of crustal magmatic stuructures beneath Mount Baekdu volcano (MBV), which is one of the largest continental intraplate volcanoes in northeast Asia. The result of our seismic imaging shows that the deeper Moho depth ( 40 km) and relatively higher shear wave velocities (>3.8 km/s) at middle-to-lower crustal depths beneath the volcano. In addition, the pattern at the bottom of our model shows that the lithosphere beneath the MBV is shallower (interpret the observations as a compositional double layering of mafic underplating and a overlying cooled felsic structure due to fractional crystallization of asthenosphere origin magma. To achieve enhanced vertical and horizontal model coverage, we apply two approaches in this work, including (1) a grid-search based phase velocity measurement using real-coherency of ambient noise data and (2) a transdimensional Bayesian joint inversion using multiple ambient noise dispersion data.

Effects of acid conditions on element distribution beneath a sulphur basepad

International Nuclear Information System (INIS)

Sevigny, J.H.; Fennell, J.W.; Sharma, A.

1997-04-01

A reconnaissance-scale study was conducted to determine the extent of acid conditions beneath a sulphur basepad at Canadian Occidental's Balzac sour gas plant and to examine the effects of acid conditions on element distribution in the subsurface. Sulphur which is extracted from sour natural gas is stored in large blocks directly on the ground. The elemental sulphur will oxidize to H 2 SO 4 under aerobic conditions and with the proper microorganisms can result in possible removal of metals from the soil and transportation in the groundwater. The basepad at the sour gas plant is 36 years old and is covered by about 1 metre of elemental sulphur. EM31 terrain conductivity and electrical resistivity tomography geophysical surveys were conducted to determine aerial and subsurface bulk electrical conductivity. The objective was to locate the indurated layer using the geophysical techniques and soil boring. The extent of acid conditions beneath the sulphur block was determined. Migration rates for the site were also estimated. Results suggested that minimal soil and groundwater impact can be expected from sulphur blocks overlying properly buffered soils, and that synthetic liners beneath sulphur blocks may not be a necessary measure at sour gas plants in Alberta. 19 refs., 6 tabs., 6 figs., 5 appendices

Silicone infusion tubing instead of Hunter rods for two-stage zone 2 flexor tendon reconstruction in a resource-limited surgical environment.

Science.gov (United States)

Kibadi, K; Moutet, F

2017-10-01

The authors describe their experience using silicone infusion tubing in place of Hunter rods for two-stage zone 2 flexor tendon reconstruction in a resource-limited surgical environment. This case report features a 47-year-old, right-handed man who had no active PIP and DIP joint flexion in four fingers of the right hand 5 months after an injury. During the first repair stage, the A2 and A4 pulleys were reconstructed using an extensor retinaculum graft. An infusion tube was inserted instead of Hunter rods. During the second stage, formation of a digital neo-canal around the infusion tubing was observed. The infusion tubing was removed and replaced with a palmaris longus tendon graft according to the conventional technique. Physiotherapy and rehabilitation followed surgery. At 6 months, very significant progress had been made with complete recovery of PIP and DIP flexion in the four fingers. Copyright © 2017 SFCM. Published by Elsevier Masson SAS. All rights reserved.

Neogene subduction beneath Java, Indonesia: Slab tearing and changes in magmatism

Science.gov (United States)

Cottam, Michael; Hall, Robert; Cross, Lanu; Clements, Benjamin; Spakman, Wim

2010-05-01

Java is a Neogene calc-alkaline volcanic island arc formed by the northwards subduction of the Indo-Australian Plate beneath Sundaland, the continental core of SE Asia. The island has a complex history of volcanism and displays unusual subduction characteristics. These characteristics are consistent with the subduction of a hole in the down going slab that was formed by the arrival of a buoyant oceanic plateau at the trench. Subduction beneath Java began in the Eocene. However, the position and character of the calc-alkaline arc has changed over time. An older Paleogene arc ceased activity in the Early Miocene. Volcanic activity resumed in the Late Miocene producing a younger arc to the north of the older arc, and continues to the present day. An episode of Late Miocene thrusting at about 7 Ma is observed throughout Java and appears to be linked to northward movement of the arc. Arc rocks display typical calc-alkaline characteristics and reflect melting of the mantle wedge and subducted sediments associated with high fluid fluxes. Between West Java and Bali the present arc-trench gap is unusually wide at about 300 km. Seismicity identifies subducted Indian Ocean lithosphere that dips north at about 20° between the trench and the arc and then dips more steeply at about 60-70° from 100 to 600 km depth. In East Java there is gap in seismicity between about 250 and 500 km. Seismic tomography shows that this gap is not an aseismic section of the subduction zone but a hole in the slab. East Java is also unusual in the presence of K-rich volcanoes, now inactive, to the north of the calc-alkaline volcanoes of the active arc. In contrast to the calc-alkaline volcanism of the main arc, these K-rich melts imply lower fluid fluxes and a different mantle source. We suggest that all these observations can be explained by the tearing of the subducting slab when a buoyant oceanic plateau arrived at the trench south of East Java at about 8 Ma. With the slab unable to subduct

Simulation of flow in the unsaturated zone beneath Pagany Wash, Yucca Mountain

International Nuclear Information System (INIS)

Kwicklis, E.M.; Healy, R.W.; Flint, A.L.

1994-01-01

A one-dimensional numerical model was created to simulate water movement beneath Pagany Wash, Yucca Mountain, Nevada. Model stratigraphy and properties were based on data obtained from boreholes UE-25 UZ No. 4 and UE-25 UZ No. 5, which was drilled in the alluvial channel and bedrock sideslope of Pagany Wash. Although unable to account for multidimensional or preferential flowpaths beneath the wash, the model proved a useful conceptual tool with which to develop hypotheses and, in some cases, provide bounding calculations. The model indicated that liquid flux decreases with depth in the upper 120 m beneath the wash, with fluxes of several tens mm/yr in the nonwelded base of the Tiva Canyon Member and fluxes on the order of a tenth mm/yr in the upper Topopah Spring Member. Capillary barrier effects were indicated by the model to significantly delay the entry of large fluxes into the potential repository horizon during periods of increasing net infiltration, and to inhibit rapid drainage of water from the nonwelded and bedded intervals into the potential repository horizon during periods of moisture redistribution. Lateral moisture redistribution can be expected to be promoted by these effects

Lower crustal relaxation beneath the Tibetan Plateau and Qaidam Basin following the 2001 Kokoxili earthquake

Science.gov (United States)

Ryder, I.; Burgmann, R.; Pollitz, F.

2011-01-01

In 2001 November a magnitude 7.8 earthquake ruptured a 400 km long portion of the Kunlun fault, northeastern Tibet. In this study, we analyse over five years of post-seismic geodetic data and interpret the observed surface deformation in terms of stress relaxation in the thick Tibetan lower crust. We model GPS time-series (first year) and InSAR line of sight measurements (years two to five) and infer that the most likely mechanism of post-seismic stress relaxation is time-dependent distributed creep of viscoelastic material in the lower crust. Since a single relaxation time is not sufficient to model the observed deformation, viscous flow is modelled by a lower crustal Burgers rheology, which has two material relaxation times. The optimum model has a transient viscosity 9 ?? 1017 Pa s, steady-state viscosity 1 ?? 1019 Pa s and a ratio of long term to Maxwell shear modulus of 2:3. This model gives a good fit to GPS stations south of the Kunlun Fault, while displacements at stations north of the fault are over-predicted. We attribute this asymmetry in the GPS residual to lateral heterogeneity in rheological structure across the southern margin of the Qaidam Basin, with thinner crust/higher viscosities beneath the basin than beneath the Tibetan Plateau. Deep afterslip localized in a shear zone beneath the fault rupture gives a reasonable match to the observed InSAR data, but the slip model does not fit the earlier GPS data well. We conclude that while some localized afterslip likely occurred during the early post-seismic phase, the bulk of the observed deformation signal is due to viscous flow in the lower crust. To investigate regional variability in rheological structure, we also analyse post-seismic displacements following the 1997 Manyi earthquake that occurred 250 km west of the Kokoxili rupture. We find that viscoelastic properties are the same as for the Kokoxili area except for the transient viscosity, which is 5 ?? 1017 Pa s. The viscosities estimated for the

Lithospheric discontinuities beneath the U.S. Midcontinent - signatures of Proterozoic terrane accretion and failed rifting

Science.gov (United States)

Chen, Chen; Gilbert, Hersh; Fischer, Karen M.; Andronicos, Christopher L.; Pavlis, Gary L.; Hamburger, Michael W.; Marshak, Stephen; Larson, Timothy; Yang, Xiaotao

2018-01-01

region of mechanically and chemically rejuvenated mantle that was likely emplaced during late Precambrian/early Cambrian rifting. These observations suggest that the lithospheric structure beneath the Reelfoot Rift may be an example of a global phenomenon in which MLDs act as weak zones that facilitate the removal of cratonic lithosphere that lies beneath.

Crustal thickness and Vp/Vs beneath the southeastern United States: Constraints from receiver function stacking

Science.gov (United States)

Yang, Q.; Gao, S. S.; Liu, K. H.

2017-12-01

To provide new constraints on crustal structure and evolution models beneath a collage of tectonic provinces in the southeastern United States, a total of 10,753 teleseismic receiver functions recorded by 125 USArray and other seismic stations are used to compute crustal thickness and Vp/Vs values. The resulting crustal thicknesses range from 25 km at the coast to 51 km beneath the peak of the southern Appalachians with an average of 36.2 km ± 5.5 km. The resulting crustal thicknesses correlate well with surface elevation and Bouguer gravity anomalies. Beneath the Atlantic Coastal Plain, the crustal thicknesses show a clear eastward thinning with a magnitude of 10 km, from about 40 km beneath the western margin to 30 km beneath the coast. The Vp/Vs values for the entire study area range from 1.71 to 1.90 with a mean value of 1.80 ± 0.04. The mean Vp/Vs value is 1.82±0.035 in the southern Appalachian Mountain. The slightly larger than normal crustal Vp/Vs for this area might be the result of significant erosion of the felsic upper crust over the past 300 million years. Alternatively, it could also suggest the existence of pervasive magmatic intrusion into the Appalachian crust. The Vp/Vs measurements in the Atlantic Coastal Plain increase toward the east, ranging from 1.75 to 1.82, probably indicating a gradual increase of mafic magmatic intrusion into thinner crust during the development of the passive continental margin.

Shear-Velocity Structure and Azimuthal and Radial Anisotropy Beneath the Kaapvaal Craton From Bayesian Inversion of Surface-Wave Data: Inferences for the Architecture and Early Evolution of Cratons

Science.gov (United States)

Lebedev, S.; Ravenna, M.; Adam, J.

2017-12-01

Seismic anisotropy provides essential information on the deformation of the lithosphere. Knowledge of anisotropy also allows us to isolate the isotropic-average seismic velocities, relatable to the lithospheric temperature and composition. We use Rayleigh and Love-wave phase velocities and their azimuthal anisotropy measured in broad period ranges across the footprint of the Southern Africa Seismic Experiment (SASE), from the Kaapvaal Craton to the Limpopo Belt. We invert the data using our recently developed, fully non-linear Markov Chain Monte Carlo method and determine, for the first time, both the isotropic-average S velocity and its radial and azimuthal anisotropy as a function of depth from the upper crust down to the asthenosphere. The probabilistic inversion provides a way to quantify non-uniqueness, using direct parameter-space sampling, and assess model uncertainties. The high-velocity anomaly indicative of the cold cratonic lithosphere bottoms at 200-250 km beneath the central and western Kaapvaal Craton, underlain by a low-velocity zone. Beneath northern Kaapvaal and Limpopo, by contrast, high velocities extend down to 300-350 km. Although this does not require a lithosphere that has maintained this thickness over a geologically long time, the data does require the mantle to be anomalously cold down to 300-350 km. Interestingly, topography correlates with the thickness of this high-velocity layer, with lower elevations where the lid is thicker. Radial shear-wave anisotropy is in the 2-5 percent range (Vsh > Vsv) from the lower crust down to 200 km, below which depth it decreases gradually. Radial variations in the amplitude of radial anisotropy show no clear relationship with those in the amplitude of azimuthal anisotropy or isotropic-average Vs anomalies. Azimuthal anisotropy changes the fast-propagation direction near the base of the lithosphere (200-300 km depth), from the laterally varying fast azimuths in the lower lithosphere to a spatially

The structure of the crust and uppermost mantle beneath Madagascar

Science.gov (United States)

Andriampenomanana, Fenitra; Nyblade, Andrew A.; Wysession, Michael E.; Durrheim, Raymond J.; Tilmann, Frederik; Julià, Jordi; Pratt, Martin J.; Rambolamanana, Gérard; Aleqabi, Ghassan; Shore, Patrick J.; Rakotondraibe, Tsiriandrimanana

2017-09-01

The lithosphere of Madagascar was initially amalgamated during the Pan-African events in the Neoproterozoic. It has subsequently been reshaped by extensional processes associated with the separation from Africa and India in the Jurassic and Cretaceous, respectively, and been subjected to several magmatic events in the late Cretaceous and the Cenozoic. In this study, the crust and uppermost mantle have been investigated to gain insights into the present-day structure and tectonic evolution of Madagascar. We analysed receiver functions, computed from data recorded on 37 broad-band seismic stations, using the H-κ stacking method and a joint inversion with Rayleigh-wave phase-velocity measurements. The thickness of the Malagasy crust ranges between 18 and 46 km. It is generally thick beneath the spine of mountains in the centre part (up to 46 km thick) and decreases in thickness towards the edges of the island. The shallowest Moho is found beneath the western sedimentary basins (18 km thick), which formed during both the Permo-Triassic Karro rifting in Gondwana and the Jurassic rifting of Madagascar from eastern Africa. The crust below the sedimentary basin thickens towards the north and east, reflecting the progressive development of the basins. In contrast, in the east there was no major rifting episode. Instead, the slight thinning of the crust along the east coast (31-36 km thick) may have been caused by crustal uplift and erosion when Madagascar moved over the Marion hotspot and India broke away from it. The parameters describing the crustal structure of Archean and Proterozoic terranes, including average thickness (40 km versus 35 km), Poisson's ratio (0.25 versus 0.26), average shear-wave velocity (both 3.7 km s-1), and thickness of mafic lower crust (7 km versus 4 km), show weak evidence of secular variation. The uppermost mantle beneath Madagascar is generally characterized by shear-wave velocities typical of stable lithosphere (∼4.5 km s-1). However

Preliminary result of P-wave speed tomography beneath North Sumatera region

Energy Technology Data Exchange (ETDEWEB)

Jatnika, Jajat [Earth Science Study Program, Institute of Technology Bandung (Indonesia); Indonesian Meteorological, Climatological and Geophysical Agency (MCGA), Jakarta (Indonesia); Nugraha, Andri Dian, E-mail: nugraha@gf.itb.ac.id [Global Geophysical Research Group, Faculty of Mining and Petroleum Engineering, Insitute of Technology Bandung (Indonesia); Wandono [Indonesian Meteorological, Climatological and Geophysical Agency (MCGA), Jakarta (Indonesia)

2015-04-24

The structure of P-wave speed beneath the North Sumatra region was determined using P-wave arrival times compiled by MCGA from time periods of January 2009 to December 2012 combining with PASSCAL data for February to May 1995. In total, there are 2,246 local earthquake events with 10,666 P-wave phases from 63 stations seismic around the study area. Ray tracing to estimate travel time from source to receiver in this study by applying pseudo-bending method while the damped LSQR method was used for the tomographic inversion. Based on assessment of ray coverage, earthquakes and stations distribution, horizontal grid nodes was set up of 30×30 km2 for inside the study area and 80×80 km2 for outside the study area. The tomographic inversion results show low Vp anomaly beneath Toba caldera complex region and around the Sumatra Fault Zones (SFZ). These features are consistent with previous study. The low Vp anomaly beneath Toba caldera complex are observed around Mt. Pusuk Bukit at depths of 5 km down to 100 km. The interpretation is these anomalies may be associated with ascending hot materials from subduction processes at depths of 80 km down to 100 km. The obtained Vp structure from local tomography will give valuable information to enhance understanding of tectonic and volcanic in this study area.

Simulation of Wave-Plus-Current Scour beneath Submarine Pipelines

DEFF Research Database (Denmark)

Eltard-Larsen, Bjarke; Fuhrman, David R.; Sumer, B. Mutlu

2016-01-01

A fully coupled hydrodynamic and morphologic numerical model was utilized for the simulation of wave-plus-current scour beneath submarine pipelines. The model was based on incompressible Reynolds-averaged Navier–Stokes equations, coupled with k-ω turbulence closure, with additional bed and suspen......A fully coupled hydrodynamic and morphologic numerical model was utilized for the simulation of wave-plus-current scour beneath submarine pipelines. The model was based on incompressible Reynolds-averaged Navier–Stokes equations, coupled with k-ω turbulence closure, with additional bed...... and suspended load descriptions forming the basis for seabed morphology. The model was successfully validated against experimental measurements involving scour development and eventual equilibrium in pure-current flows over a range of Shields parameters characteristic of both clear-water and live-bed regimes....... This validation complements previously demonstrated accuracy for the same model in simulating pipeline scour processes in pure-wave environments. The model was subsequently utilized to simulate combined wave-plus-current scour over a wide range of combined Keulegan–Carpenter numbers and relative current strengths...

Statistical Validation of Calibrated Wind Data Collected From NOAA's Hurricane Hunter Aircraft

Science.gov (United States)

Graham, K.; Sears, I. T.; Holmes, M.; Henning, R. G.; Damiano, A. B.; Parrish, J. R.; Flaherty, P. T.

2015-12-01

Obtaining accurate in situ meteorological measurements from the NOAA G-IV Hurricane Hunter Aircraft currently requires annual wind calibration flights. This project attempts to demonstrate whether an alternate method to wind calibration flights can be implemented using data collected from many previous hurricane, winter storm, and surveying flights. Wind derivations require using airplane attack and slip angles, airplane pitch, pressure differentials, dynamic pressures, ground speeds, true air speeds, and several other variables measured by instruments on the aircraft. Through the use of linear regression models, future wind measurements may be fit to past statistical models. This method of wind calibration could replace the need for annual wind calibration flights, decreasing NOAA expenses and providing more accurate data. This would help to ensure all data users have reliable data and ultimately contribute to NOAA's goal of building of a Weather Ready Nation.

Rabbit hunter uveitis: case report of tularemia uveitis.

Science.gov (United States)

Terrada, Céline; Azza, Said; Bodaghi, Bahram; Le Hoang, Phuc; Drancourt, Michel

2016-09-01

Literature reports on ophthalmological manifestations related to tularemia, a zoonose caused by the bacterium Francisella tularensis, largely refer to Parinaud's oculoglandular syndrome, which consists of the association of conjunctivitis with preauricular lymphadenitis. In this paper, we report a case of intraocular inflammation during tularemia infection. A 52-year-old Caucasian man was diagnosed with unilateral uveitis. The uveitis was posterior, with a 2+ vitritis and a large yellowish lesion involving the macula with an overlying sub-retinal detachment, extending inferiorly, and subretinal hemorrhages. Fluorescein angiography showed a late hyperfluorescence with focal vascular leakage. Ultrasound biomicroscopy confirmed the presence of a 3.8 mm parietal granuloma with a few calcifications in the left eye. While extensive work-up eliminated any other infectious and non-infectious etiology, tularemia was diagnosed by advanced serology consisting of two-dimensional Western-immunoblotting. The patient, a hunter, recalled having killed rabbits in the days before the symptoms appeared. Uveitis was rapidly controlled following treatment with doxycycline, yet three years after initiation of the treatment, the patient still complained of loss of vision in the left eye with a central scotoma. Posterior uveitis may be an infrequent manifestation of tularemia infection, and therefore this infection should be considered in the differential diagnosis of intraocular inflammation in areas where F. tularensis is endemic.

Large-scale global convection in the mantle beneath Australia from 55 Ma to now

International Nuclear Information System (INIS)

Zhang, M.

1999-01-01

Full text: The global-scale mantle convection cells in the asthenosphere are not geochemically homogeneous. The heterogeneity is most prominently reflected in the isotopic compositions (Pb-Sr-Nd) of the mid-ocean ridge basalts (MORB) that are direct partial melts from the underlying asthenosphere. Of particular relevance to Australia's geodynamic evolution from about 100 million years, are the distinctive geochemical signatures of the asthenosphere beneath the Pacific Ocean (Pacific MORB) and Indian Ocean (Indian MORB). Therefore, delineation of the boundary between the two distinct mantle reservoirs and any change in that boundary with time provide information about the patterns of global-scale asthenospheric mantle convection. This information has also allowed us to track large-scale mantle chemical reservoirs such as the distinctive Gondwana lithospheric mantle, and hence better understand the geodynamic evolution of the Australian continent from the time of Gondwana dispersal. Pb-Sr-Nd isotope data for Cenozoic basalts in eastern Australia (Zhang et al, 1999) indicate that Pacific-MORB type isotopic signatures characterise the lava-field basalts (55-14 Ma) in southeastern Australia, whereas Indian-MORB type isotopic signatures characterise younger basalts (6-0 Ma) from northeastern Australia. This discovery helps to constrain the changing locus of the major asthenospheric mantle convection cells represented by the Pacific and Indian MORB sources during and following the breakup of the eastern part of Gondwana, and locates, for the first time, the boundary of these convection cells beneath the Australian continent. This extends previous work in the SW Pacific back-arc basins (eg Hickey-Vargas et al., 1995) and the Southern Ocean (Lanyon et al., 1995) that indicates that the 1- and P-MORB mantle convection cells have been moving in opposite directions since the early Tertiary. These new data also indicate that the Indian-MORB source is a long-term asthenospheric

Living and Working Beneath the Sea – Next Approach

Directory of Open Access Journals (Sweden)

Rowiński Lech

2017-04-01

Full Text Available The idea of living beneath the sea is very new if compared with millennia of shipping activity. In fact, ocean surface was considered mainly as medium suitable for transport of persons and goods as well as aggression and robbery. More practical attempts to live “on” the water surface are limited to well protected internal waters.

Late Pleistocene and Early Holocene Rock Art from the Mongolian Altai: The Material and its Cultural Implications

Directory of Open Access Journals (Sweden)

Esther Jacobson-Tepfer

2013-09-01

Full Text Available Rock-pecked images from the northern Mongolian Altai attest to the presence of human communities within the high valleys of that region during the Late Pleistocene and Early Holocene. The material provides evidence that is hitherto largely missing from the archaeological record of that region. This paper reviews the rock art, its find sites and larger physical contexts and uses evidence from paleoenvironmental studies to propose dating and cultural significance. The material is compared with other sites said to have Paleolithic imagery from Mongolia and the adjoining Russian Altai. The body of presented material offers a major resource for the study of early hunter-gatherer communities at the interface of Central and North Asia.

Networks of Food Sharing Reveal the Functional Significance of Multilevel Sociality in Two Hunter-Gatherer Groups.

Science.gov (United States)

Dyble, Mark; Thompson, James; Smith, Daniel; Salali, Gul Deniz; Chaudhary, Nikhil; Page, Abigail E; Vinicuis, Lucio; Mace, Ruth; Migliano, Andrea Bamberg

2016-08-08

Like many other mammalian and primate societies [1-4], humans are said to live in multilevel social groups, with individuals situated in a series of hierarchically structured sub-groups [5, 6]. Although this multilevel social organization has been described among contemporary hunter-gatherers [5], questions remain as to the benefits that individuals derive from living in such groups. Here, we show that food sharing among two populations of contemporary hunter-gatherers-the Palanan Agta (Philippines) and Mbendjele BaYaka (Republic of Congo)-reveals similar multilevel social structures, with individuals situated in households, within sharing clusters of 3-4 households, within the wider residential camps, which vary in size. We suggest that these groupings serve to facilitate inter-sexual provisioning, kin provisioning, and risk reduction reciprocity, three levels of cooperation argued to be fundamental in human societies [7, 8]. Humans have a suite of derived life history characteristics including a long childhood and short inter-birth intervals that make offspring energetically demanding [9] and have moved to a dietary niche that often involves the exploitation of difficult to acquire foods with highly variable return rates [10-12]. This means that human foragers face both day-to-day and more long-term energetic deficits that conspire to make humans energetically interdependent. We suggest that a multilevel social organization allows individuals access to both the food sharing partners required to buffer themselves against energetic shortfalls and the cooperative partners required for skill-based tasks such as cooperative foraging. Copyright © 2016 Elsevier Ltd. All rights reserved.

Utilizing hunter harvest effort to survey for wildlife disease: a case study of West Nile virus in greater sage-grouse

Science.gov (United States)

Dusek, Robert J.; Hagen, Christian A.; Franson, J. Christian; Budeau, David A.; Hofmeister, Erik K.

2014-01-01

Greater sage-grouse (Centrocercus urophasianus; sage-grouse) are highly susceptible to infection with West Nile virus (WNV), with substantial mortality reported in wild populations and in experimentally infected birds. Although sage-grouse are hunted throughout much of their range, they have also recently been considered for protection under the Endangered Species Act. We used blood samples collected on filter-paper strips during the 2006–2010 Oregon, USA, annual sage-grouse hunt to survey for specific WNV-neutralizing antibodies that indicate a previous infection with WNV. During this period, hunters submitted 1,880 blood samples from sage-grouse they harvested. Samples obtained were proportional for all 12 Oregon sage-grouse hunting units. Laboratory testing of 1,839 samples by the WNV epitope-blocking enzyme-linked immunosorbent assay (bELISA) followed by plaque reduction neutralization test on bELISA-positive samples yielded 19 (1%) and 1 (0.05%) positive samples, respectively. These data provided early baseline information for future comparisons regarding the prevalence of WNV-specific neutralizing antibodies in sage-grouse in Oregon. This methodology may provide other states where sage-grouse (or other species) populations are hunted and where WNV constitutes a species conservation concern with a viable option to track the relative prevalence of the virus in populations.

Portrait of a Geothermal Spring, Hunter's Hot Springs, Oregon.

Science.gov (United States)

Castenholz, Richard W

2015-01-27

Although alkaline Hunter's Hot Springs in southeastern Oregon has been studied extensively for over 40 years, most of these studies and the subsequent publications were before the advent of molecular methods. However, there are many field observations and laboratory experiments that reveal the major aspects of the phototrophic species composition within various physical and chemical gradients of these springs. Relatively constant temperature boundaries demark the upper boundary of the unicellular cyanobacterium, Synechococcus at 73-74 °C (the world-wide upper limit for photosynthesis), and 68-70 °C the upper limit for Chloroflexus. The upper limit for the cover of the filamentous cyanobacterium, Geitlerinema (Oscillatoria) is at 54-55 °C, and the in situ lower limit at 47-48 °C for all three of these phototrophs due to the upper temperature limit for the grazing ostracod, Thermopsis. The in situ upper limit for the cyanobacteria Pleurocapsa and Calothrix is at ~47-48 °C, which are more grazer-resistant and grazer dependent. All of these demarcations are easily visible in the field. In addition, there is a biosulfide production in some sections of the springs that have a large impact on the microbiology. Most of the temperature and chemical limits have been explained by field and laboratory experiments.

Parental experience of enzyme replacement therapy for Hunter syndrome.

Science.gov (United States)

Buraczewska, M; O'Leary, D; Walsh, O; Monavari, A; Crushell, E

2013-04-01

We aimed to establish the profile of Irish patients with Hunter Syndrome (Mucopolysaccharidosis type II, MPS II) receiving weekly intravenous Enzyme Replacement Therapy (ERT) with recombinant iduronate-2-sulfatase and to assess the social impact and parental opinion of ERT through the use of a parental questionnaire. Nine patients aged 3.5- 14 years have received a mean of 2 (range 0.5-3.5) years of ERT. Treatment was associated with clinical improvements from baseline in hepatosplenomegaly in 6/7 (85%) respiratory manifestations in 4/6 (67%) and a mean reduction in urinary glycosaminoglycan excretion of 62%. Changes noted by parents included increased energy 3/9 (33%) and softening of skin, hair and facial features 8/9 (89%). Parents report that seven hours weekly were spent on hospitalizations for ERT. Parental employment was adversely affected in 8 (89%) families. One day of school/preschool (20%) was lost every week for 8 (89%) children. All parents believed the benefits of ERT out-weigh the difficulties involved. All families would welcome the introduction of home based therapy. In conclusion the social and educational burden of hospital-based ERT on these children and their families is significant. The introduction of home-based therapy is likely to improve overall quality of life for MPSII patients and their families.

Subsurface imaging reveals a confined aquifer beneath an ice-sealed Antarctic lake

DEFF Research Database (Denmark)

Dugan, H. A.; Doran, P. T.; Tulaczyk, S.

2015-01-01

Liquid water oases are rare under extreme cold desert conditions found in the Antarctic McMurdo Dry Valleys. Here we report geophysical results that indicate that Lake Vida, one of the largest lakes in the region, is nearly frozen and underlain by widespread cryoconcentrated brine. A ground...... this zone to be a confined aquifer situated in sediments with a porosity of 23-42%. Discovery of this aquifer suggests that subsurface liquid water may be more pervasive in regions of continuous permafrost than previously thought and may represent an extensive habitat for microbial populations. Key Points...... Geophysical survey finds low resistivities beneath a lake in Antarctic Dry Valleys Liquid brine abundant beneath Antarctic lake Aquifer provides microbial refugium in cold desert environment...

Isotopic discontinuities in ground water beneath Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Stuckless, J.S.; Whelan, J.F.; Steinkampf, W.C.

1991-01-01

Analytical data for stable isotopes in ground water from beneath Yucca Mountain, when examined in map view, show areal patterns of heterogeneity that can be interpreted in terms of mixing of at least three end members. One end member must be isotopically heavy in terms of hydrogen and oxygen and have a young apparent 14 C age such as water found at the north end of Yucca Mountain beneath Fortymile Wash. A second end member must contain isotopically heavy carbon and have an old apparent 14 C age such as water from the Paleozoic aquifer. The third end member cannot be tightly defined. It must be isotopically lighter than the first with respect of hydrogen and oxygen and be intermediate to the first and second end members with respect to both apparent 14 C age and δ 13 C. The variable isotopic compositions of hydrogen and oxygen indicate that two of the end members are waters, but the variable carbon isotopic composition could represent either a third water end member or reaction of water with a carbon-bearing solids such as calcite. 15 refs., 4 figs., 1 tab

New Pn and Sn tomographic images of the uppermost mantle beneath the Mediterranean region

Science.gov (United States)

Gil, A.; Díaz, J.; Gallart, J.

2012-04-01

We present here new images of the seismic velocity and anisotropy variations in the uppermost mantle beneath the Mediterranean region, compiled from inversion of Pn and Sn phases. The method of Hearn (1996) has been applied to Pn and Sn lectures from the catalogs of the International Seismological Center and the Spanish Instituto Geografico Nacional. A total of 1,172,293 Pn arrivals coming from 16,527 earthquakes recorded at 1,657 stations with epicentral distances between 220 km and 1400 km have been retained (331,567 arrivals from 15,487events at 961 stations for Sn). Our results, grossly consistent with available 3D tomography images, show significant features well correlated with surface geology. The Pn velocities are high (>8.2 km/s) beneath major sedimentary basins (western Alboran Sea, Valencia Trough, Adriatic Sea, Aquitaine, Guadalquivir, Rharb, Aquitaine and Po basins), and low (Islands, probably related to a thermal anomaly associated to the westward displacement of the Alboran block along the Emile Baudot escarpment 16 Ma ago. The Pn anisotropic image shows consistent orientations sub-parallel to major orogenic structures, such as Betics, Apennines, Calabrian Arc and Alps. The station delays beneath Betic and Rif ranges are strongly negative, suggesting the presence of crustal thickening all along the Gibraltar Arc. However, only the Betics have a very strong low-velocity anomaly and a pronounced anisotropy pattern. The Sn tomographic image correlates well with the Pn image, even if some relevant differences can be observed beneath particular regions.

Petrological constraints on melt generation beneath the Asal Rift (Djibouti) using quaternary basalts

Science.gov (United States)

Pinzuti, Paul; Humler, Eric; Manighetti, Isabelle; Gaudemer, Yves

2013-08-01

The temporal evolution of the mantle melting processes in the Asal Rift is evaluated from the chemical composition of 56 new lava flows sampled along 10 km of the rift axis and 9 km off-axis (i.e., erupted within the last 620 kyr). Petrological and primary geochemical results show that most of the samples of the inner floor of the Asal Rift are affected by plagioclase accumulation. Trace element ratios and major element compositions corrected for mineral accumulation and crystallization show a symmetric pattern relative to the rift axis and preserved a clear signal of mantle melting depth variations. While FeO, Fe8.0, Zr/Y, and (Dy/Yb)N decrease from the rift shoulders to the rift axis, SiO2, Na/Ti, Lu/Hf increase and Na2O and Na8.0 are constant across the rift. These variations are qualitatively consistent with shallow melting beneath the rift axis and deeper melting for off-axis lava flows. Na8.0 and Fe8.0 contents show that beneath the rift axis, melting paths are shallow, from 81 ± 4 to 43 ± 5 km. These melting paths are consistent with adiabatic melting in normal-temperature fertile asthenosphere, beneath an extensively thinned mantle lithosphere. On the contrary, melting on the rift shoulders (from 107 ± 7 to 67 ± 8 km) occurred beneath thicker lithosphere, requiring a mantle solidus temperature 100 ± 40°C hotter. In this geodynamic environment, the calculated rate of lithospheric thinning appears to be 4.0 ± 2.0 cm yr-1, a value close to the mean spreading rate (2.9 ± 0.2 cm yr-1) over the last 620 kyr.

Multiple-frequency tomography of the upper mantle beneath the African/Iberian collision zone

Science.gov (United States)

Bonnin, Mickaël; Nolet, Guust; Villaseñor, Antonio; Gallart, Josep; Thomas, Christine

2014-09-01

During the Cenozoic, the geodynamics of the western Mediterranean domain has been characterized by a complex history of subduction of Mesozoic oceanic lithosphere. The final stage of these processes is proposed to have led to the development of the Calabria and Gibraltar arcs, whose formation is still under debate. In this study, we take advantage of the dense broad-band station networks now available in the Alborán Sea region, to develop a high-resolution 3-D tomographic P velocity model of the upper mantle beneath the African/Iberian collision zone that will better constraint the past dynamics of this zone. The model is based on 13200 teleseismic arrival times recorded between 2008 and 2012 at 279 stations for which cross-correlation delays are measured with a new technique in different frequency bands centred between 0.03 and 1.0 Hz, and for the first time interpreted using multiple frequency tomography. Our model shows, beneath the Alborán Sea, a strong (4 per cent) fast vertically dipping anomaly observed to at least 650 km depth. The arched shape of this anomaly, and its extent at depth, are coherent with a lithospheric slab, thus favouring the hypothesis of a westward consumption of the Ligurian ocean slab by roll-back during Cenozoic. In addition to this fast anomaly in the deep upper mantle, high intensity slow anomalies are widespread in the lithosphere and asthenosphere beneath Morocco and southern Spain. These anomalies are correlated at the surface with the position of the Rif and Atlas orogens and with Cenozoic volcanic fields. We thus confirm the presence, beneath Morocco, of an anomalous (hot?) upper mantle, but without clear indication for a lateral spreading of the Canary plume to the east.

A detailed map of the 660-kilometer discontinuity beneath the izu-bonin subduction zone.

Science.gov (United States)

Wicks, C W; Richards, M A

1993-09-10

Dynamical processes in the Earth's mantle, such as cold downwelling at subduction zones, cause deformations of the solid-state phase change that produces a seismic discontinuity near a depth of 660 kilometers. Observations of short-period, shear-to-compressional wave conversions produced at the discontinuity yield a detailed map of deformation beneath the Izu-Bonin subduction zone. The discontinuity is depressed by about 60 kilometers beneath the coldest part of the subducted slab, with a deformation profile consistent with the expected thermal signature of the slab, the experimentally determined Clapeyron slope of the phase transition, and the regional tectonic history.

Una valigia caduta in mare: Jaume Serra Hunter e la "Scuola di Barcellona"

Directory of Open Access Journals (Sweden)

Nazzareno Fioraso

2014-12-01

Full Text Available Nella storiografia filosofica spagnola non esiste, probabilmente, una definizione ambigua e problematica come quella che riguarda la cosiddetta "Scuola di Barcellona". La tesi principale di questo articolo è che tale scuola non giunse mai a nascere, ma ne esistette soltanto una forma embrionale che non poté maturare perché, in conseguenza della situazione politica venutasi a creare con la guerra civile (1936-1939, i suoi componenti si dispersero nell'esilio. Ciò nonostante, è possibile riconoscere alcuni tratti comuni, seppur labili e (forse non sostanziali, nella diaspora degli intellettuali catalani che rendono possibile definirla, con le dovute cautele, "Scuola di Barcellona". Tali caratteristiche comuni si possono far risalire a colui che, in un certo senso, fu il fondatore della scuola, essendo il principale maestro delle nuove leve filosofiche della Catalogna all'inizio del XX secolo: Jaume Serra Hunter.

Results of the radiological survey at West Hunter Avenue Firehall, Maywood, New Jersey (MJ027)

International Nuclear Information System (INIS)

Foley, R.D.; Floyd, L.M.

1990-03-01

Maywood Chemical Works (MCW) of Maywood, New Jersey, generated process wastes and residues associated with the production and refining of thorium and thorium compounds from monazite ores from 1916 to 1956. At the request of the US Department of Energy (DOE), a group from Oak Ridge National Laboratory conducts investigative radiological surveys of properties in the vicinity of MCW to determine whether a property is contaminated with radioactive residues, principally 232 Th, derived from the MCW site. The survey typically includes direct measurement of gamma radiation levels and soil sampling for radionuclide analyses. The survey of this site, West Hunter Avenue Firehall, Maywood, New Jersey (MJ027), was conducted during 1987. 4 refs., 3 tabs

Predicting hunter behavior of indigenous communities in the Ecuadorian Amazon: insights from a household production model

Directory of Open Access Journals (Sweden)

Enrique de la Montaña

2015-12-01

Full Text Available Many indigenous communities living in the Amazon rely on hunting and fishing to meet the majority of their protein needs. Despite the importance of these practices, few studies from the region have analyzed the socioeconomic drivers of hunting and fishing at the household level. We propose a household production model to assess the effect of key economic parameters on hunting and fishing in small indigenous communities located in the Ecuadorian Amazon, whose principal source of protein is derived from hunting and fishing. The model was validated using empirical data from two communities that reflect different levels of market integration and forest conservation. Demand and supply functions were generated from household data gathered over 19 months. Elasticities were derived to determine the sensitivity of the decision to engage in hunting to exogenous parameters such as off-farm wages, hunting costs, bushmeat price, penalties for the illegal sale of bushmeat, and biological characteristics of the game species. After calibrating the model, we simulated changes in the key economic parameters. The parameter that most directly affected hunting activity in both communities was off-farm wages. Simulating a 10% wage increase resulted in a 16-20% reduction in harvested biomass, while a 50% increase diminished harvested biomass by > 50%. Model simulations revealed that bushmeat price and penalties for illegal trade also had important effects on hunter behavior in terms of amount of bushmeat sold, but not in terms of total harvest. As a tool for understanding hunters' economic decision-making, the model provides a basis for developing strategies that promote sustainable hunting and wildlife conservation while protecting indigenous livelihoods.

Deep groundwater and potential subsurface habitats beneath an Antarctic dry valley

DEFF Research Database (Denmark)

Mikucki, J. A.; Auken, E.; Tulaczyk, S.

2015-01-01

The occurrence of groundwater in Antarctica, particularly in the ice-free regions and along the coastal margins is poorly understood. Here we use an airborne transient electromagnetic (AEM) sensor to produce extensive imagery of resistivity beneath Taylor Valley. Regional-scale zones of low subsu...

Origin of HTLV-1 in hunters of nonhuman primates in Central Africa.

Science.gov (United States)

Kazanji, Mirdad; Mouinga-Ondémé, Augustin; Lekana-Douki-Etenna, Sonia; Caron, Mélanie; Makuwa, Maria; Mahieux, Renaud; Gessain, Antoine

2015-02-01

Of 78 Gabonese individuals who had received bites from nonhuman primates (NHPs) while hunting, 7 were infected with human T lymphotropic virus (HTLV-1). Five had been bitten by gorillas and were infected with subtype B strains; however, a 12-year-old girl who was severely bitten by a Cercopithecus nictitans was infected with a subtype D strain that was closely related to the simian T lymphotropic virus (STLV-1) that infects this monkey species. Her mother was infected with a subtype B strain. These data confirm that hunters in Africa can be infected by HTLV-1 that is closely related to the strains circulating among local NHP game. Our findings strongly suggest that a severe bite represent a risk factor for STLV-1 acquisition. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Review: Recharge rates and chemistry beneath playas of the High Plains aquifer, USA

Science.gov (United States)

Gurdak, Jason J.; Roe, Cassia D.

2010-12-01

Playas are ephemeral, closed-basin wetlands that are hypothesized as an important source of recharge to the High Plains aquifer in central USA. The ephemeral nature of playas, low regional recharge rates, and a strong reliance on groundwater from the High Plains aquifer has prompted many questions regarding the contribution and quality of recharge from playas to the High Plains aquifer. As a result, there has been considerable scientific debate about the potential for water to infiltrate the relatively impermeable playa floors, travel through the unsaturated zone sediments that are tens of meters thick, and subsequently recharge the High Plains aquifer. This critical review examines previously published studies on the processes that control recharge rates and chemistry beneath playas. Reported recharge rates beneath playas range from less than 1.0 to more than 500 mm/yr and are generally 1-2 orders of magnitude higher than recharge rates beneath interplaya settings. Most studies support the conceptual model that playas are important zones of recharge to the High Plains aquifer and are not strictly evaporative pans. The major findings of this review provide science-based implications for management of playas and groundwater resources of the High Plains aquifer and directions for future research.

Structure of the Crust Beneath Cameroon, West Africa, from the Joint Inversion of Rayleigh Wave Group Velocities and Receiver Functions

International Nuclear Information System (INIS)

Tokam, Alain-Pierre K.; Tabod, Charles T.; Nyblade, Andrew A.; Jordi Julia; Wiens, Douglas A.; Pasyanos, Michael E.

2009-09-01

The joint inversion of Rayleigh wave group velocities and receiver functions was carried out to investigate the crustal and uppermost mantle structures beneath Cameroon. This was achieved using data from 32 broadband seismic stations installed for 2 years across Cameroon. The Moho depth estimates reveal that the Precambrian crust is variable across the country and shows some significant differences compared to other similar geologic units in East and South Africa. These differences suggest that the setting of the Cameroon Volcanic Line (CVL) and the eastward extension of the Benue Trough have modified the crust of the Panafrican mobile belt in Cameroon by thinning beneath the Rift area and CVL. The velocity models obtained from the joint inversion show at most stations, a layer with shear wave velocities ≥ 4.0 km/s, indicating the presence of a mafic component in the lower crust, predominant beneath the Congo Craton. The lack of this layer at stations within the Panafrican mobile belt may partly explain the crustal thinning observed beneath the CVL and rift area. The significant presence of this layer beneath the Craton, results from the 2100 Ma magmatic events at the origin of the emplacement of swarms of mafic dykes in the region. The CVL stations are underlain by a crust of 35 km on average except near Mt-Cameroon where it is about 25 km. The crustal thinning observed beneath Mt. Cameroon supported by the observed positive gravity anomalies here, suggests the presence of dense astenospheric material within the lithosphere. Shear wave velocities are found to be slower in the crust and uppermost mantle beneath the CVL than the nearby tectonic terrains, suggesting that the origin of the line may be an entirely mantle process through the edge-flow convection process. (author)

The crustal structure beneath The Netherlands derived from ambient seismic noise

NARCIS (Netherlands)

Yudistira, Tedi; Paulssen, Hanneke; Trampert, Jeannot

2017-01-01

This work presents the first comprehensive 3-D model of the crust beneath The Netherlands. To obtain this model, we designed the NARS-Netherlands project, a dense deployment of broadband stations in the area. Rayleigh and Love wave group velocity dispersion was measured from ambient noise

Seismic Structure of Mantle Transition Zone beneath Northwest Pacific Subduction Zone and its Dynamic Implication

Science.gov (United States)

Li, J.; Guo, G.; WANG, X.; Chen, Q.

2017-12-01

The northwest Pacific subduction region is an ideal location to study the interaction between the subducting slab and upper mantle discontinuities. Various and complex geometry of the Pacific subducting slab can be well traced downward from the Kuril, Japan and Izu-Bonin trench using seismicity and tomography images (Fukao and Obayashi, 2013). Due to the sparse distribution of seismic stations in the sea, investigation of the deep mantle structure beneath the broad sea regions is very limited. In this study, we applied the well- developed multiple-ScS reverberations method (Wang et al., 2017) to analyze waveforms recorded by the Chinese Regional Seismic Network, the densely distributed temporary seismic array stations installed in east Asia. A map of the topography of the upper mantle discontinuities beneath the broad oceanic regions in northwest Pacific subduction zone is imaged. We also applied the receiver function analysis to waveforms recorded by stations in northeast China and obtain the detailed topography map beneath east Asia continental regions. We then combine the two kinds of topography of upper mantle discontinuities beneath oceanic and continental regions respectively, which are obtained from totally different methods. A careful image matching and spatial correlation is made in the overlapping study regions to calibrate results with different resolution. This is the first time to show systematically a complete view of the topography of the 410-km and 660-km discontinuities beneath the east Asia "Big mantle wedge" (Zhao and Ohtani, 2009) covering the broad oceanic and continental regions in the Northwestern Pacific Subduction zone. Topography pattern of the 660 and 410 is obtained and discussed. Especially we discovered a broad depression of the 410-km discontinuity covering more than 1000 km in lateral, which seems abnormal in the cold subducting tectonic environment. Based on plate tectonic reconstruction studies and HTHP mineral experiments, we

Radial viscous fingering of hot asthenosphere within the Icelandic plume beneath the North Atlantic Ocean

Science.gov (United States)

Schoonman, C. M.; White, N. J.; Pritchard, D.

2017-06-01

The Icelandic mantle plume has had a significant influence on the geologic and oceanographic evolution of the North Atlantic Ocean during Cenozoic times. Full-waveform tomographic imaging of this region shows that the planform of this plume has a complex irregular shape with significant shear wave velocity anomalies lying beneath the lithospheric plates at a depth of 100-200 km. The distribution of these anomalies suggests that about five horizontal fingers extend radially beneath the fringing continental margins. The best-imaged fingers lie beneath the British Isles and beneath western Norway where significant departures from crustal isostatic equilibrium have been measured. Here, we propose that these radial fingers are generated by a phenomenon known as the Saffman-Taylor instability. Experimental and theoretical analyses show that fingering occurs when a less viscous fluid is injected into a more viscous fluid. In radial, miscible fingering, the wavelength and number of fingers are controlled by the mobility ratio (i.e. the ratio of viscosities), by the Péclet number (i.e. the ratio of advective and diffusive transport rates), and by the thickness of the horizontal layer into which fluid is injected. We combine shear wave velocity estimates with residual depth measurements around the Atlantic margins to estimate the planform distribution of temperature and viscosity within a horizontal asthenospheric layer beneath the lithospheric plate. Our estimates suggest that the mobility ratio is at least 20-50, that the Péclet number is O (104), and that the asthenospheric channel is 100 ± 20 km thick. The existence and planform of fingering is consistent with experimental observations and with theoretical arguments. A useful rule of thumb is that the wavelength of fingering is 5 ± 1 times the thickness of the horizontal layer. Our proposal has been further tested by examining plumes of different vigor and planform (e.g. Hawaii, Cape Verde, Yellowstone). Our results

Crustal thickness and Moho sharpness beneath the Midcontinent rift from receiver functions

Directory of Open Access Journals (Sweden)

Moikwathai Moidaki

2013-02-01

Full Text Available The Mesoproterozoic Midcontinent rift (MCR in the central US is an approximately 2000 km long, 100 km wide structure from Kansas to Michigan. During the 20-40 million years of rifting, a thick (up to 20 km layer of basaltic lava was deposited in the rift valleys. Quantifying the effects of the rifting and associated volcanic eruptions on the structure and composition of the crust and mantle beneath the MCR is important for the understanding of the evolution of continental lithosphere. In this study we measure the crustal thickness (H, and the sharpness of the Moho (R at about 24 portable and permanent stations in Iowa, Kansas, and South Dakota by stacking Pto- S converted waves (PmS and their multiples (PPmS and PSmS. Under the assumption that the crustal mean velocity in the study area is the same as the IASP91 earth model, we find a significantly thickened crust beneath the MCR of about 53 km. The crustal Vp/Vs ratios increases from about 1.80 off rift to as large as 1.95 within the rift, which corresponds to an increase of Poisson’s ratio from 0.28 to 0.32, suggesting a more mafic crust beneath the MCR. The R measurements are spatially variable and are relatively small in the vicinity of the MCR, indicating the disturbance of the original sharp Moho by the rifting and magmatic intrusion and volcanic eruption.

Treatment of Chlorinated Solvents in Groundwater Beneath an Occupied Building at the Young-Rainey STAR Center, Pinellas, FL

Energy Technology Data Exchange (ETDEWEB)

Daniel, Joe [Navarro Research and Engineering; Surovchak, Scott [Dept. of Energy (DOE), Legacy Management; Tabor, Charles [Navarro Research and Engineering

2016-03-01

Groundwater contamination, consisting of two dissolved-phase plumes originating from chlorinated solvent source areas, in the southeastern portion of the Young- Rainey Star Center (also known as the Pinellas County, Florida, Site) in Largo, Florida, has migrated beyond the property boundary, beneath the roadways, and beneath adjacent properties to the south and east. Groundwater contamination will persist as long as the onsite contaminant source remains. The origin of the contamination appears to be multiple long-term point sources beneath Building 100, a 4.5 ha (11 acre) building that housed manufacturing facilities during US DOE operations at the site. The site is now owned by Pinellas County, and most of the space inside the building is leased to private companies, so DOE chose not to conduct characterization or remediation through the floor of the building, instead choosing to conduct all work from outside the building. Injection of emulsified soybean oil and a microbial culture has been used at other areas of the site to accelerate naturally occurring bacterial processes that degrade groundwater contaminants to harmless compounds, and that same approach was chosen for this task. The technical approach consisted of installing horizontal wells from outside the building footprint, extending through and around the identified subsurface treatment areas, and terminating beneath the building. Two 107 m (350 ft) long wells, two 122 m (400 ft) long wells, and four 137 m (450 ft) long wells have been installed to intersect the inferred source areas and confirmed contaminant plumes beneath the building. DOE then injected emulsified vegetable oil and a microbial culture into the horizontal wells at each of several target areas beneath the building where the highest groundwater contaminant concentrations have been detected. The target areas are the northwest corner of the building between the old drum storage pad locations and monitoring well PIN12-S35B, the vicinity of

Early Life Conditions and Physiological Stress following the Transition to Farming in Central/Southeast Europe: Skeletal Growth Impairment and 6000 Years of Gradual Recovery.

Directory of Open Access Journals (Sweden)

Alison A Macintosh

Full Text Available Early life conditions play an important role in determining adult body size. In particular, childhood malnutrition and disease can elicit growth delays and affect adult body size if severe or prolonged enough. In the earliest stages of farming, skeletal growth impairment and small adult body size are often documented relative to hunter-gatherer groups, though this pattern is regionally variable. In Central/Southeast Europe, it is unclear how early life stress, growth history, and adult body size were impacted by the introduction of agriculture and ensuing long-term demographic, social, and behavioral change. The current study assesses this impact through the reconstruction and analysis of mean stature, body mass, limb proportion indices, and sexual dimorphism among 407 skeletally mature men and women from foraging and farming populations spanning the Late Mesolithic through Early Medieval periods in Central/Southeast Europe (~7100 calBC to 850 AD. Results document significantly reduced mean stature, body mass, and crural index in Neolithic agriculturalists relative both to Late Mesolithic hunter-gatherer-fishers and to later farming populations. This indication of relative growth impairment in the Neolithic, particularly among women, is supported by existing evidence of high developmental stress, intensive physical activity, and variable access to animal protein in these early agricultural populations. Among subsequent agriculturalists, temporal increases in mean stature, body mass, and crural index were more pronounced among Central European women, driving declines in the magnitude of sexual dimorphism through time. Overall, results suggest that the transition to agriculture in Central/Southeast Europe was challenging for early farming populations, but was followed by gradual amelioration across thousands of years, particularly among Central European women. This sex difference may be indicative, in part, of greater temporal variation in the

Early Life Conditions and Physiological Stress following the Transition to Farming in Central/Southeast Europe: Skeletal Growth Impairment and 6000 Years of Gradual Recovery

Science.gov (United States)

Macintosh, Alison A.; Pinhasi, Ron; Stock, Jay T.

2016-01-01

Early life conditions play an important role in determining adult body size. In particular, childhood malnutrition and disease can elicit growth delays and affect adult body size if severe or prolonged enough. In the earliest stages of farming, skeletal growth impairment and small adult body size are often documented relative to hunter-gatherer groups, though this pattern is regionally variable. In Central/Southeast Europe, it is unclear how early life stress, growth history, and adult body size were impacted by the introduction of agriculture and ensuing long-term demographic, social, and behavioral change. The current study assesses this impact through the reconstruction and analysis of mean stature, body mass, limb proportion indices, and sexual dimorphism among 407 skeletally mature men and women from foraging and farming populations spanning the Late Mesolithic through Early Medieval periods in Central/Southeast Europe (~7100 calBC to 850 AD). Results document significantly reduced mean stature, body mass, and crural index in Neolithic agriculturalists relative both to Late Mesolithic hunter-gatherer-fishers and to later farming populations. This indication of relative growth impairment in the Neolithic, particularly among women, is supported by existing evidence of high developmental stress, intensive physical activity, and variable access to animal protein in these early agricultural populations. Among subsequent agriculturalists, temporal increases in mean stature, body mass, and crural index were more pronounced among Central European women, driving declines in the magnitude of sexual dimorphism through time. Overall, results suggest that the transition to agriculture in Central/Southeast Europe was challenging for early farming populations, but was followed by gradual amelioration across thousands of years, particularly among Central European women. This sex difference may be indicative, in part, of greater temporal variation in the social status afforded

Analysis of pumping-induced unsaturated regions beneath aperennial river

Energy Technology Data Exchange (ETDEWEB)

Su, G.W.; Jasperse, J.; Seymour, D.; Constantz, J.; Zhou, Q.

2007-05-15

The presence of an unsaturated region beneath a streambedduring groundwater pumping near streams reduces the pumping capacity whenit reaches the well screens, changes flow paths, and alters the types ofbiological transformations in the streambed sediments. Athree-dimensional, multi-phase flow model of two horizontal collectorwells along the Russian River near Forestville, California was developedto investigate the impact of varying the ratio of the aquifer tostreambed permeability on (1) the formation of an unsaturated regionbeneath the stream, (2) the pumping capacity, (3) stream-water fluxesthrough the streambed, and (4) stream-water travel times to the collectorwells. The aquifer to streambed permeability ratio at which theunsaturated region was initially observed ranged from 10 to 100. The sizeof the unsaturated region beneath the streambed increased as the aquiferto streambed permeability ratio increased. The simulations also indicatedthat for a particular aquifer permeability, decreasing the streambedpermeability by only a factor of 2-3 from the permeability wheredesaturation initially occurred resulted in reducing the pumpingcapacity. In some cases, the stream-water fluxes increased as thestreambed permeability decreased. However, the stream water residencetimes increased and the fraction of stream water that reached that thewells decreased as the streambed permeability decreased, indicating thata higher streambed flux does not necessarily correlate to greaterrecharge of stream water around the wells.

76 FR 54051 - Migratory Bird Hunting; Final Frameworks for Early-Season Migratory Bird Hunting Regulations

Science.gov (United States)

2011-08-30

... season dates, shooting hours, and daily bag and possession limits for the 2011-12 season. These... weekend, holidays, or other non-school days when youth hunters would have the maximum opportunity to... hunters would encounter whooping cranes. Kentucky has also opted to delay legal shooting hours until...

Variations in Crust and Upper Mantle Structure Beneath Diverse Geologic Provinces in Asia

National Research Council Canada - National Science Library

Schwartz, Susan H

1997-01-01

This report presents results of a two year effort to determine crust and mantle lithospheric structure beneath Eurasia and to explore the effects that structural variations have on regional wave propagation...

Nutrition, modernity and the archaeological record: coastal resources and nutrition among Middle Stone Age hunter-gatherers on the Western Cape coast of South Africa.

Science.gov (United States)

Kyriacou, Katharine; Parkington, John E; Marais, Adrian D; Braun, David R

2014-12-01

In this paper, we assess the nutritional value of some marine and terrestrial food resources available to Middle Stone Age hunter-gatherers in the Western Cape of South Africa with respect to an important macronutrient (protein) and an essential micronutrient (iron) and introduce a framework for assessing the relative utility of marine and terrestrial resources. Whilst the ability to extract nutrients from the environment has always been a lynchpin in archaeologists' reconstructions of human evolution, a recent paradigm shift has recognized the role of marine resources in encephalization. Nutritional research indicates that marine ecosystems are the best source for long chain polyunsaturated fatty acids essential for proper brain development, and excavations at securely dated archaeological sites in South Africa provide firm evidence for the exploitation of marine resources by Middle Stone Age hunter-gatherers from at least Marine Isotope Stage 5 (130 ka), and possibly even earlier. Because marine molluscs are abundant, predictably located and easily harvested, they would have been readily available to all members of the community, in contrast to terrestrial resources. The improving archaeological record gives important clues to resource choice, but many more nutritional observations are needed to determine the extent to which marine resources could have met the nutrient requirements of prehistoric people. Our observations indicate that marine and terrestrial fauna are both excellent sources of protein, and that marine molluscs have higher iron concentrations than we expected for invertebrate fauna. We calculate the number of individual food items from a selection of marine and terrestrial species needed to provide the protein and iron requirements of a hypothetical group of hunter-gatherers, identify contrasts in peoples' requirements for and access to nutrients and resources, and discuss the implications for prehistoric subsistence strategies and human evolution

Detailed Configuration of the Underthrusting Indian Lithosphere Beneath Western Tibet Revealed by Receiver Function Images

Science.gov (United States)

Xu, Qiang; Zhao, Junmeng; Yuan, Xiaohui; Liu, Hongbing; Pei, Shunping

2017-10-01

We analyze the teleseismic waveform data recorded by 42 temporary stations from the Y2 and ANTILOPE-1 arrays using the P and S receiver function techniques to investigate the lithospheric structure beneath western Tibet. The Moho is reliably identified as a prominent feature at depths of 55-82 km in the stacked traces and in depth migrated images. It has a concave shape and reaches the deepest location at about 80 km north of the Indus-Yarlung suture (IYS). An intracrustal discontinuity is observed at 55 km depth below the southern Lhasa terrane, which could represent the upper border of the eclogitized underthrusting Indian lower crust. Underthrusting of the Indian crust has been widely observed beneath the Lhasa terrane and correlates well with the Bouguer gravity low, suggesting that the gravity anomalies in the Lhasa terrane are induced by topography of the Moho. At 20 km depth, a midcrustal low-velocity zone (LVZ) is observed beneath the Tethyan Himalaya and southern Lhasa terrane, suggesting a layer of partial melts that decouples the thrust/fold deformation of the upper crust from the shortening and underthrusting in the lower crust. The Sp conversions at the lithosphere-asthenosphere boundary (LAB) can be recognized at depths of 130-200 km, showing that the Indian lithospheric mantle is underthrusting with a ramp-flat shape beneath southern Tibet and probably is detached from the lower crust immediately under the IYS. Our observations reconstruct the configuration of the underthrusting Indian lithosphere and indicate significant along strike variations.

Analysis of PFAAs in American alligators part 2: Potential dietary exposure of South Carolina hunters from recreationally harvested alligator meat.

Science.gov (United States)

Tipton, Jessica J; Guillette, Louis J; Lovelace, Susan; Parrott, Benjamin B; Rainwater, Thomas R; Reiner, Jessica L

2017-11-01

Exposure to perfluorinated alkyl acids (PFAAs) has been linked to many harmful health effects including reproductive disorders, developmental delays, and altered liver and kidney function. Most human exposure to environmental contaminants, including PFAAs, occurs through consumption of contaminated food or drinking water. This study uses PFAA data from meat samples collected from recreationally harvested American alligators (Alligator mississippiensis) in South Carolina to assess potential dietary exposure of hunters and their families to PFAAs. Consumption patterns were investigated using intercept surveys of 23 hunters at a wild game meat processor. An exposure scenario using the average consumption frequency, portion size, and median perfluorooctane sulfonic acid (PFOS) concentration in alligator meat from all hunt units found the daily dietary exposure to be 2.11ng/kg body weight per day for an adult human. Dietary PFOS exposure scenarios based on location of harvest suggested the highest daily exposure occurs with alligator meat from the Middle Coastal hunt unit in South Carolina. Although no samples were found to exceed the recommended threshold for no consumption of PFOS found in Minnesota state guidelines, exposure to a mixture of PFAAs found in alligator meat and site-specific exposures based on harvest location should be considered in determining an appropriate guideline for vulnerable populations potentially exposed to PFAAs through consumption of wild alligator meat. Copyright © 2017. Published by Elsevier B.V.

Velocity Models of the Upper Mantle Beneath the MER, Somali Platform, and Ethiopian Highlands from Body Wave Tomography

Science.gov (United States)

Hariharan, A.; Keranen, K. M.; Alemayehu, S.; Ayele, A.; Bastow, I. D.; Eilon, Z.

2016-12-01

The Main Ethiopian Rift (MER) presents a unique opportunity to improve our understanding of an active continental rift. Here we use body wave tomography to generate compressional and shear wave velocity models of the region beneath the rift. The models help us understand the rifting process over the broader region around the MER, extending the geographic region beyond that captured in past studies. We use differential arrival times of body waves from teleseismic earthquakes and multi-channel cross correlation to generate travel time residuals relative to the global IASP91 1-d velocity model. The events used for the tomographic velocity model include 200 teleseismic earthquakes with moment magnitudes greater than 5.5 from our recent 2014-2016 deployment in combination with 200 earthquakes from the earlier EBSE and EAGLE deployments (Bastow et al. 2008). We use the finite-frequency tomography analysis of Schmandt et al. (2010), which uses a first Fresnel zone paraxial approximation to the Born theoretical kernel with spatial smoothing and model norm damping in an iterative LSQR algorithm. Results show a broad, slow region beneath the rift with a distinct low-velocity anomaly beneath the northwest shoulder. This robust and well-resolved low-velocity anomaly is visible at a range of depths beneath the Ethiopian plateau, within the footprint of Oligocene flood basalts, and near surface expressions of diking. We interpret this anomaly as a possible plume conduit, or a low-velocity finger rising from a deeper, larger plume. Within the rift, results are consistent with previous work, exhibiting rift segmentation and low-velocities beneath the rift valley.

Sea-level change and demography during the last glacial termination and early Holocene across the Australian continent

Science.gov (United States)

Williams, Alan N.; Ulm, Sean; Sapienza, Tom; Lewis, Stephen; Turney, Chris S. M.

2018-02-01

Future changes in sea-level are projected to have significant environmental and social impacts, but we have limited understanding of comparable rates of change in the past. Using comprehensive palaeoenvironmental and archaeological datasets, we report the first quantitative model of the timing, spatial extent and pace of sea-level change in the Sahul region between 35-8 ka, and explore its effects on hunter-gatherer populations. Results show that the continental landmass (excluding New Guinea) increased to 9.80 million km2 during the Last Glacial Maximum (LGM), before a reduction of 2.12 million km2 (or ∼21.6%) to the early Holocene (8 ka). Almost 90% of this inundation occurs during and immediately following Meltwater Pulse (MWP) 1a between 14.6 and 8 ka. The location of coastlines changed on average by 139 km between the LGM and early Holocene, with some areas >300 km, and at a rate of up to 23.7 m per year (∼0.6 km land lost every 25-year generation). Spatially, inundation was highly variable, with greatest impacts across the northern half of Australia, while large parts of the east, south and west coastal margins were relatively unaffected. Hunter-gatherer populations remained low throughout (hypothesis that late Pleistocene coastal populations were low, with use of coastal resources embedded in broad-ranging foraging strategies, and which would have been severely disrupted in some regions and at some time periods by sea-level change outpacing tolerances of mangals and other near-shore ecological communities.

Crustal structure beneath Beijing and its surrounding regions derived from gravity data

Science.gov (United States)

Jiang, Wenliang; Zhang, Jingfa; Lu, Xiaocui; Lu, Jing

2011-06-01

In this paper we use gravity data to study fine crustal structure and seismogenic environment beneath Beijing and its surrounding regions. Multi-scale wavelet analysis method is applied to separating gravity fields. Logarithmic power spectrum method is also used to calculate depth of gravity field source. The results show that the crustal structure is very complicated beneath Beijing and its surrounding areas. The crustal density exhibits laterally inhomogeneous. There are three large scale tectonic zones in North China, i.e., WNW-striking Zhangjiakou-Bohai tectonic zone (ZBTZ), NE-striking Taihang piedmont tectonic zone (TPTZ) and Cangxian tectonic zone (CTZ). ZBTZ and TPTZ intersect with each other beneath Beijing area and both of them cut through the lithosphere. The upper and middle crusts consist of many small-scale faults, uplifts and depressions. In the lower crust, these small-scale tectonic units disappear gradually, and they are replaced by large-scale tectonic units. In surrounding regions of Beijing, ZBTZ intersects with several other NE-striking tectonic units, such as Cangxian uplift, Jizhong depression and Shanxi Graben System (SGS). In west of Taihangshan uplift, gravity anomalies in upper and middle crusts are correlated with geological and topographic features on the surface. Compared with the crust, the structure is comparatively simple in uppermost mantle. Earthquakes mainly occurred in upper and middle crusts, especially in transitional regions between high gravity anomaly and low gravity anomaly. Occurrence of large earthquakes may be related to the upwelling of upper mantle and asthenosphere heat flow materials, such as Sanhe earthquake ( M S8.0) and Tangshan earthquake ( M S7.8).

Mechanism for migration of light nonaqueous phase liquids beneath the water table

International Nuclear Information System (INIS)

Krueger, J.P.; Portman, M.E.

1991-01-01

This paper reports on an interesting transport mechanism may account for the presence of light nonaqueous phase liquid (LNAPL) found beneath the water table in fine-grained aquifers. During the course of two separate site investigations related to suspected releases from underground petroleum storage tanks, LNAPL was found 7 to 10 feet below the regional water table. In both cases, the petroleum was present within a sand seam which was encompassed within a deposit of finer-grained sediments. The presence of LNAPL below the water table is uncommon; typically, LNAPL is found floating on the water table or on the capillary fringe. The occurrence of LNAPL below the water table could have resulted from fluctuating regional water levels which allowed the petroleum to enter the sand when the water table was a lower stage or, alternately, could have occurred as a result of the petroleum depressing the water table beneath the level of the sand. In fine-grained soils where the lateral migration rate is low, the infiltrating LNAPL may depress the water table to significant depth. The LNAPL may float on the phreatic surface with the bulk of its volume beneath the phreatic surface. Once present in the sand and surrounded by water-saturated fine-grained sediments, capillary forces prevent the free movement of the petroleum back across the boundary from the coarse-grained sediments to the fine-grained sediments. Tapping these deposits with a coarser grained filter packed monitoring well releases the LNAPL, which may accumulate to considerable thickness in the monitoring well

Identifying biogeochemical processes beneath stormwater infiltration ponds in support of a new best management practice for groundwater protection

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O'Reilly, Andrew M.; Chang, Ni-Bin; Wanielista, Martin P.; Xuan, Zhemin; Schirmer, Mario; Hoehn, Eduard; Vogt, Tobias

2011-01-01

 When applying a stormwater infiltration pond best management practice (BMP) for protecting the quality of underlying groundwater, a common constituent of concern is nitrate. Two stormwater infiltration ponds, the SO and HT ponds, in central Florida, USA, were monitored. A temporal succession of biogeochemical processes was identified beneath the SO pond, including oxygen reduction, denitrification, manganese and iron reduction, and methanogenesis. In contrast, aerobic conditions persisted beneath the HT pond, resulting in nitrate leaching into groundwater. Biogeochemical differences likely are related to soil textural and hydraulic properties that control surface/subsurface oxygen exchange. A new infiltration BMP was developed and a full-scale application was implemented for the HT pond. Preliminary results indicate reductions in nitrate concentration exceeding 50% in soil water and shallow groundwater beneath the HT pond.

Low-Q structure beneath The Geysers area in the northern California

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Matsubara, M.

2010-12-01

A large reservoir is located beneath The Geysers geothermal area, northern California. Seismic tomography revealed high-velocity (high-V) and low-Vp/Vs zones in the reservoir (Julian et al., 1996) and a decrease of Vp/Vs from 1991 to 1998 (Guasekera et al., 2003) due to withdrawal of steam from the reservoir. I build on these earlier studies by performing the attenuation tomography in this region to investigate the Q structure. The target region, 38.5-39.0°N and 122.5-123°W, covers The Geysers area. I use seismographs of Northern California Earthquake Data Center, which recorded 1235 earthquakes with magnitude larger than 2.0 and resolved focal mechanisms from 2002 to 2008. The band-pass filtered seismographs are analyzed for collecting the maximum amplitude data. Three kinds of Butterworth band-pass filters, such as 1-3, 3-7, and 7-15, correspond to the analysis of the Q structure for 2, 5, and 10 Hz, respectively. I use the P- and S-wave maximum amplitudes between the two seconds after the arrival of those waves in order to avoid the effects by coda. A total of 8980 P- and 1086 S-wave amplitude data for 949 earthquakes recorded at 48 stations are available for the analysis using the attenuation tomographic method (Zao et al., 1996). Extremely low-Qp and Qs zones are found at the northwestern (NW) of The Geysers area at sea level. These zones are consistent with the high-Vp and Vs and low-Vp/Vs zones located at the NW part of the reservoir. The low-Qs zone extends to the southeast (SE) and with approximately 15 km length and 5 km width and has another negative peak beneath the SE part of the reservoir. This low-Qs zone is also consistent with the high-Vp and Vs regions of the reservoir characterized by a low-Vp/Vs zone. However, Qp in the SE part is slightly high. Below sea level in The Geysers reservoir, there are a main greywacke layer and a felsite layer. Above sea level, there is a greenstone melange beneath the NW extremely low-Qp and Qs region and a

Ceramics among Eurasian hunter-gatherers: 32 000 years of ceramic technology use and the perception of containment

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Mihael Budja

2016-12-01

Full Text Available We present two parallel and 32 000 years long trajectories of episodic ceramic technology use in Eurasian pre-Neolithic hunter-gatherer societies. In eastern, Asian trajectory the pottery was produced from the beginning. Ceramic figurines mark the western, European trajectory. The western predates the eastern for about eleven millennia. While ceramic cones and figurines first appeared in Central Europe at c. 31 000 cal BC the earliest vessels in eastern Asia was dated at c. 20 000 cal BC. We discuss women’s agency, perception of containment, ‘cross-craft interactions’, and evolution of private property that that may influenced the inventions of ceramic (pyrotechnology.

Throughfall and its spatial variability beneath xerophytic shrub canopies within water-limited arid desert ecosystems

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Zhang, Ya-feng; Wang, Xin-ping; Hu, Rui; Pan, Yan-xia

2016-08-01

Throughfall is known to be a critical component of the hydrological and biogeochemical cycles of forested ecosystems with inherently temporal and spatial variability. Yet little is understood concerning the throughfall variability of shrubs and the associated controlling factors in arid desert ecosystems. Here we systematically investigated the variability of throughfall of two morphological distinct xerophytic shrubs (Caragana korshinskii and Artemisia ordosica) within a re-vegetated arid desert ecosystem, and evaluated the effects of shrub structure and rainfall characteristics on throughfall based on heavily gauged throughfall measurements at the event scale. We found that morphological differences were not sufficient to generate significant difference (P < 0.05) in throughfall between two studied shrub species under the same rainfall and meteorological conditions in our study area, with a throughfall percentage of 69.7% for C. korshinskii and 64.3% for A. ordosica. We also observed a highly variable patchy pattern of throughfall beneath individual shrub canopies, but the spatial patterns appeared to be stable among rainfall events based on time stability analysis. Throughfall linearly increased with the increasing distance from the shrub base for both shrubs, and radial direction beneath shrub canopies had a pronounced impact on throughfall. Throughfall variability, expressed as the coefficient of variation (CV) of throughfall, tended to decline with the increase in rainfall amount, intensity and duration, and stabilized passing a certain threshold. Our findings highlight the great variability of throughfall beneath the canopies of xerophytic shrubs and the time stability of throughfall pattern among rainfall events. The spatially heterogeneous and temporally stable throughfall is expected to generate a dynamic patchy distribution of soil moisture beneath shrub canopies within arid desert ecosystems.

CONDICIÓN FÍSICA Y HÁBITOS DE PRÁCTICA FÍSICO-DEPORTIVA DE LOS CAZADORES EXTREMEÑOS [Physical condition and habits of practice exercise of hunters extremeños

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José Martín Gamonales Puerto

2016-12-01

Present study analyses the physical condition and the physical-sportive exercise in a random sample of hunters (n=144 in the Extremadura (Spain. Hunting is recognized as a sportive modality by the Board of the CDS (Spanish High Sports Council. In order to know the physical condition levels in hunters group, were used a selection of Eurofit and AFISAL-INEFC tests for adult. Final results show the relation which exist between physical condition and sociodemographic differences, as well as the influence that hunting can have in a healthy lifestyle. Attending to the results, there are differences in the physical condition according to the age of the individuals. Moreover, it shows a relation between the sociodemographic characteristics of the sample and the additional physical-sportive exercises of the different modalities of hunting.

Bathymetry and ocean properties beneath Pine Island Glacier revealed by Autosub3 and implications for recent ice stream evolution (Invited)

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Jenkins, A.; Dutrieux, P.; McPhail, S.; Perrett, J.; Webb, A.; White, D.; Jacobs, S. S.

2009-12-01

The Antarctic ice sheet, which represents the largest of all potential contributors to sea level rise, appears to be losing mass at a rate that has accelerated over recent decades. Ice loss is focussed in a number of key drainage basins where dynamical changes in the outlet glaciers have led to increased discharge. The synchronous response of several independent glaciers, coupled with the observation that thinning is most rapid over their floating termini, is generally taken as an indicator that the changes have been driven from the ocean. Some of the most significant changes have been observed on Pine Island Glacier, where thinning, acceleration and grounding line retreat have all been observed, primarily through satellite remote sensing. Even during the relatively short satellite record, rates of change have been observed to increase. Between 20th and 30th January 2009 the Autosub3 autonomous underwater vehicle was deployed from host ship RVIB Nathaniel B Palmer on six sorties into the ocean cavity beneath Pine Island Glacier. Total track length was 887 km (taking 167 hours) of which 510 km (taking 94 hours) were beneath the glacier. Some of the main aims were to map both the seabed beneath and the underside of the glacier and to investigate how warm Circumpolar Deep Water (CDW) flows beneath Pine Island Glacier and determines its melt rate. Among the instruments carried by Autosub-3 were a Seabird CTD, with dual conductivity and temperature sensors plus a dissolved oxygen sensor and a transmissometer, a multi-beam echosounder that could be configured to look up or down, and two Acoustic Doppler Current Profilers (ADCPs): an upward-looking 300 kHz instrument and a downward-looking 150 kHz instrument, providing a record of ice draft and seabed depth along the vehicle track. The ADCP data reveal an apparently continuous ridge with an undulating crest that extends across the cavity about 30km in from the current ice front. This topographic feature blocks CDW inflow

Moessbauer spectroscopic study of corrosion products beneath primer coating containing anticorrosive pigments

International Nuclear Information System (INIS)

Kumar, A.V.R.; Nigam, R.K.

1998-01-01

The phase analysis of the rusts generated beneath the primer containing micaceous iron oxide (MIO) and micaceous iron oxide in combination with red lead (RL), zinc phosphate (ZP), basic lead silicochromate (BLSC) and zinc chromate (ZC) has been carried out by Moessbauer spectroscopy at room temperature. The rust beneath the coating obtained after immersion of the painted panel for six months in 3% NaCl, consists mainly of non-stoichiometric magnetite together with small fractions of γ-, α-FeOOH except in the case of panel painted with RL containing MIO showed only a central doublet indicating the formation of γ-FeOOH and SPM α-FeOOH. Non-stoichiometry of magnetite as calculated from the ratio of B/A sites of the peaks of magnetite in the spectrum has been found depending on the nature of anticorrosive pigment present in the primer coating. The order of non-stoichiometry has been found to be in order of ZC > BLSC > ZP > MIO. (author)

Late Glacial to Early Holocene socio-ecological responses to climatic instability within the Mediterranean basin

Science.gov (United States)

Fernández-López de Pablo, Javier; Jones, Samantha E.; Burjachs, Francesc

2018-03-01

The period spanning the Late Glacial and the Early Holocene (≈19-8.2 ka) witnessed a dramatic sequence of climate and palaeoenvironmental changes (Rasmussen et al., 2014). Interestingly, some of the most significant transformations ever documented in human Prehistory took place during this period such as the intensification of hunter-gatherer economic systems, the domestication process of wild plants and animals, and the spread of farming across Eurasia. Understanding the role of climate and environmental dynamics on long-term cultural and economic trajectories, as well as specific human responses to episodes of rapid climate change, still remains as one of the main challenges of archaeological research (Kintigh et al., 2014).

Complex structure of the lithospheric slab beneath the Banda arc, eastern Indonesia depicted by a seismic tomographic model

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Sri Widiyantoro

2011-10-01

Full Text Available Seismic tomography with a non-linear approach has been successfully applied to image the P-wave velocity structure beneath the Banda arc in detail. Nearly one million compressional phases including the surfacereflected depth phases pP and pwP from events within the Indonesian region have been used. The depth phases have been incorporated in order to improve the sampling of the uppermantle structure, particularly below the Banda Sea in the back-arc regions. For the model parameterization, we have combined a highresolution regional inversion with a low-resolution global inversion to allow detailed images of slab structures within the study region and to minimize the mapping of distant aspherical mantle structure into the volume under study. In this paper, we focus our discussion on the upper mantle and transition zone structure beneath the curved Banda arc. The tomographic images confirm previous observations of the twisting of the slab in the upper mantle, forming a spoon-shaped structure beneath the Banda arc. A slab lying flat on the 660 km discontinuity beneath the Banda Sea is also well imaged. Further interpretations of the resulting tomograms and seismicity data support the scenario of the Banda arc subduction rollback.

Depth variations of the 410 and 520 km-discontinuities beneath Asia and the Pacific from PP precursors

Science.gov (United States)

Schäfer, J.; Wölbern, I.; Rümpker, G.

2009-06-01

We investigate depth variations of the 410 and 520 km-discontinuities beneath Asia and the Pacific which serve as examples for a continental and an oceanic region, respectively. The depths are derived from travel-time differences between the PP-phase and its precursors that are reflected at the discontinuities. After accounting for differences in average crustal thickness, we find that the depth of the ‘410’ is rather uniform but larger than expected beneath both regions with a value of approximately 418 km. Signals from the ‘520’ are slightly less pronounced. However, while the average depth of the ‘520’ beneath Asia is about 519 km, we obtain a value of about 531.5 km for the Pacific. Here, the depression of the discontinuities can be explained in view of thermal anomalies in relation to mantle plumes. For Asia, however, the observations seem to require a more complex pattern of thermal anomalies possibly complemented by variations in chemical composition.

Molecular characterization of Histoplasma capsulatum isolated from an outbreak in treasure hunters Histoplasma capsulatum in treasure hunters

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Muñoz Bertha

2010-09-01

Full Text Available Abstract Background In Mexico, primary pulmonary histoplasmosis is the most relevant clinical form of the disease. The geographical distribution of specific strains of Histoplasma capsulatum circulating in Mexico has not been fully established. Outbreaks must be reported in order to have current, updated information on this disease, identifying new endemic areas, manner of exposure to the fungi, and molecular characterization of the causative agents. We report a recent outbreak of histoplasmosis in treasure hunters and the molecular characterization of two isolates obtained from these patients. Methods Six patients admitted to the National Institute of Respiratory Diseases (INER in Mexico City presented severe respiratory symptoms suggestive of histoplasmosis. They acquired the infection in the Veracruz (VZ endemic zone. Diagnosis was made by X-ray and Computed tomography (CT, liver function, immunological techniques, and culture. Identification of H. capsulatum isolates was confirmed by using Polymerase chain reaction (PCR was conducted with a probe from the M antigen, and the isolates were characterized by means of Random amplification of polymorphic DNA (RAPD-PCR employed the 1253 oligonucleotide and a mixture of oligonucleotides 1281 and 1283. These were compared to eight reference strain isolates from neighboring areas. Results X-ray and CT revealed disseminated micronodular images throughout lung parenchyma, as well as bilateral retrocaval, prevascular, subcarinal, and hilar adenopathies, hepatosplenomegaly, and altered liver function tests. Five of the six patients developed disseminated histoplasmosis. Two H. capsulatum strains were isolated. The same band profile was detected in both strains, indicating that both isolates corresponded to the sole H. capsulatum strain. Molecular characterization of the isolates was similar in 100% with the EH-53 Hidalgo human (HG strain (reference strain integrated into the LAm A clade described for

Chemical evolution of the early Martian hydrosphere

International Nuclear Information System (INIS)

Schaefer, M.W.

1990-01-01

The chemical evolution of the early Martian hydrosphere is discussed. The early Martian ocean can be modeled as a body of relatively pure water in equilibrium with a dense carbon dioxide atmosphere. The chemical weathering of lavas, pyroclastic deposits, and impact melt sheets would have the effect of neutralizing the acidity of the juvenile water. As calcium and other cations are added to the water by chemical weathering, they are quickly removed by the precipitation of calcium carbonate and other minerals, forming a deposit of limestone beneath the surface of the ocean. As the atmospheric carbon dioxide pressure and the temperature decrease, the Martian ocean would be completely frozen. Given the scenario for the chemical evolution of the northern lowland plains of Mars, it should be possible to draw a few conclusions about the expected mineralogy and geomorphology of this regions

Predicting scour beneath subsea pipelines from existing small free span depths under steady currents

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Jun Y. Lee

2017-06-01

Full Text Available An equation was developed to predict current-induced scour beneath subsea pipelines in areas with small span depths, S. Current equations for scour prediction are only applicable to partially buried pipelines. The existence of small span depths (i.e. S/D < 0.3 are of concern because the capacity for scour is higher at smaller span depths. Furthermore, it is impractical to perform rectification works, such as installing grout bags, under a pipeline with a small S/D. Full-scale two-dimensional computational fluid dynamics (CFD simulations were performed using the Reynolds-averaged Navier–Stokes approach and the Shear stress transport k–ω turbulence model. To predict the occurrence of scour, the computed maximum bed shear stress beneath the pipe was converted to the dimensionless Shields parameter, and compared with the critical Shields parameter based on the mean sediment grain size. The numerical setup was verified, and a good agreement was found between model-scale CFD data and experimental data. Field data were obtained to determine the mean grain size, far field current velocity and to measure the span depths along the surveyed pipe length. A trend line equation was fitted to the full-scale CFD data, whereby the maximum Shields parameter beneath the pipe can be calculated based on the undisturbed Shields parameter and S/D.

Mapping the mantle transition zone beneath the central Mid-Atlantic Ridge using Ps receiver functions.

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Agius, M. R.; Rychert, C.; Harmon, N.; Kendall, J. M.

2017-12-01

Determining the mechanisms taking place beneath ridges is important in order to understand how tectonic plates form and interact. Of particular interest is establishing the depth at which these processes originate. Anomalies such as higher temperature within the mantle transition zone may be inferred seismically if present. However, most ridges are found in remote locations beneath the oceans restricting seismologists to use far away land-based seismometers, which in turn limits the imaging resolution. In 2016, 39 broadband ocean-bottom seismometers were deployed across the Mid-Atlantic Ridge, along the Romanche and Chain fracture zones as part of the PI-LAB research project (Passive Imaging of the Lithosphere and Asthenosphere Boundary). The one-year long seismic data is now retrieved and analysed to image the mantle transition zone beneath the ridge. We determine P-to-s (Ps) receiver functions to illuminate the 410- and 660-km depth mantle discontinuities using the extended multitaper deconvolution. The data from ocean-bottom seismometers have tilt and compliance noise corrections and is filtered between 0.05-0.2 Hz to enhance the signal. 51 teleseismic earthquakes generated hundreds of good quality waveforms, which are then migrated to depth in 3-D. The topography at the d410 deepens towards the west of the Romanche and Chain fracture zone by 15 km, whereas the topography of d660 shallows beneath the ridge between the two zones. Transition zone thickness thins from 5 to 20 km. Thermal anomalies determined from temperature relationships with transition zone thickness and depth variations of the d410 and d660 suggests hotter temperatures of about 200 K. Overall, the result suggests mid-ocean ridges may have associated thermal signatures as deep as the transition zone.

Proving communal warfare among hunter-gatherers: The Quasi-Rousseauan error.

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Gat, Azar

2015-01-01

Was human fighting always there, as old as our species? Or is it a late cultural invention, emerging after the transition to agriculture and the rise of the state, which began, respectively, only around ten thousand and five thousand years ago? Viewed against the life span of our species, Homo sapiens, stretching back 150,000-200,000 years, let alone the roughly two million years of our genus Homo, this is the tip of the iceberg. We now have a temporal frame and plenty of empirical evidence for the "state of nature" that Thomas Hobbes and Jean-Jacque Rousseau discussed in the abstract and described in diametrically opposed terms. All human populations during the Pleistocene, until about 12,000 years ago, were hunter-gatherers, or foragers, of the simple, mobile sort that lacked accumulated resources. Studying such human populations that survived until recently or still survive in remote corners of the world, anthropology should have been uniquely positioned to answer the question of aboriginal human fighting or lack thereof. Yet access to, and the interpretation of, that information has been intrinsically problematic. The main problem has been the "contact paradox." Prestate societies have no written records of their own. Therefore, documenting them requires contact with literate state societies that necessarily affects the former and potentially changes their behavior, including fighting. © 2015 Wiley Periodicals, Inc.

Comparative Study on the Electrical Properties of the Oceanic Mantle Beneath the Northwest Pacific Ocean

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Toh, H.

2013-12-01

We have been conducting long-term seafloor electromagnetic (EM) observations at two sites in the northwest Pacific since 2001. The older site was established at the deep seafloor (~5600m) on the northwest Pacific basin (Site NWP), while the new one was installed on the west Philippine basin (Site WPB) in 2006 at the slightly deeper (~5700m) seafloor. The ages of the oceanic basins at those sites are approximately 129 Ma for Site NWP (Shipboard Scientific Party of ODP Leg 191, 2000) and 49 Ma for Site WPB (Salisbury et al., 2006), respectively. The EM instruments deployed at those sites are seafloor EM stations (SFEMS; Toh et al., 2004 and 2006) and capable of measuring vector EM fields at the seafloor for as long as one year or more with other physical quantities such as the instruments' attitude, orientation and temperature. One of the objectives of the seafloor long-term EM observations by SFEMSs is to make a comparative study of the oceanic mantle with and without influence of the so-called 'stagnant slabs' in terms of their electrical conductivity. It is anticipated that the mantle transition zone under the influence of the stagnant slab has a higher electrical conductivity because the transition zone there could be wetter than that in the absence of the stagnant slab. In this context, the mantle transition zone beneath Site WPB can be said to have influence by the stagnant slab, while that beneath Site NWP does not. It, therefore, is basically possible to estimate how much water is present in each transition zone by comparison of the electrical conductivity profiles of the two. The one-dimensional electrical profile beneath Site NWP has been derived so far using the magnetotelluric (MT) and geomagnetic depth sounding (GDS) methods with significant jumps in the electrical property at 410 and 660km discontinuities. The jumps are approximately factors of 10 and 2, respectively (Ichiki et al., 2009). Here we show a profile beneath Site WPB using both MT and GDS

Smoke flow temperature beneath tunnel ceiling for train fire at subway station: Reduced-scale experiments and correlations

International Nuclear Information System (INIS)

Meng, Na; Wang, Qiang; Liu, Zhaoxia; Li, Xiao; Yang, He

2017-01-01

Highlights: • Reduced-scale experiments on train fire at subway station. • Smoke flow temperature beneath tunnel ceiling measured and correlated. • Effect of platform-tunnel conjunction door type on smoke temperature is clarified. - Abstract: This paper is to investigate the smoke flow temperature beneath tunnel ceiling for a train on fire stopping besides a subway station. Experiments were carried out in a reduced-scale (1:10) subway station model to study the maximum smoke temperature and the longitudinal temperature distribution beneath the tunnel ceiling by considering platform-tunnel conjunction doors of two types: the full-seal platform screen door (PSD) and the full-height safety door. For the maximum temperature beneath the tunnel ceiling, it is found to be well correlated non-dimensionally with heat release rate by a 3.65 and a 2.92 power law function for the full-seal platform screen door and the full-height safety door, respectively. For the longitudinal temperature distribution along the tunnel ceiling, it can be well correlated by an exponential function for both types of platform-tunnel conjunction doors. Concerning the effect of the door type, the maximum temperature is lower and the longitudinal temperature decays faster for full-height safety door than that for full-seal PSD. This is due to that with the full-height safety door, the effective width of the tunnel ceiling is widened, which results in more heat losses from the smoke flow to the ceiling.

Prey items and predation behavior of killer whales (Orcinus orca) in Nunavut, Canada based on Inuit hunter interviews

Science.gov (United States)

2012-01-01

Background Killer whales (Orcinus orca) are the most widely distributed cetacean, occurring in all oceans worldwide, and within ocean regions different ecotypes are defined based on prey preferences. Prey items are largely unknown in the eastern Canadian Arctic and therefore we conducted a survey of Inuit Traditional Ecological Knowledge (TEK) to provide information on the feeding ecology of killer whales. We compiled Inuit observations on killer whales and their prey items via 105 semi-directed interviews conducted in 11 eastern Nunavut communities (Kivalliq and Qikiqtaaluk regions) from 2007-2010. Results Results detail local knowledge of killer whale prey items, hunting behaviour, prey responses, distribution of predation events, and prey capture techniques. Inuit TEK and published literature agree that killer whales at times eat only certain parts of prey, particularly of large whales, that attacks on large whales entail relatively small groups of killer whales, and that they hunt cooperatively. Inuit observations suggest that there is little prey specialization beyond marine mammals and there are no definitive observations of fish in the diet. Inuit hunters and elders also documented the use of sea ice and shallow water as prey refugia. Conclusions By combining TEK and scientific approaches we provide a more holistic view of killer whale predation in the eastern Canadian Arctic relevant to management and policy. Continuing the long-term relationship between scientists and hunters will provide for successful knowledge integration and has resulted in considerable improvement in understanding of killer whale ecology relevant to management of prey species. Combining scientists and Inuit knowledge will assist in northerners adapting to the restructuring of the Arctic marine ecosystem associated with warming and loss of sea ice. PMID:22520955

Rayleigh Wave Phase Velocities Beneath the Central and Southern East African Rift System

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Adams, A. N.; Miller, J. C.

2017-12-01

This study uses the Automated Generalized Seismological Data Function (AGSDF) method to develop a model of Rayleigh wave phase velocities in the central and southern portions of the East African Rift System (EARS). These phase velocity models at periods of 20-100s lend insight into the lithospheric structures associated with surficial rifting and volcanism, as well as basement structures that pre-date and affect the course of rifting. A large dataset of >700 earthquakes is used, comprised of Mw=6.0+ events that occurred between the years 1995 and 2016. These events were recorded by a composite array of 176 stations from twelve non-contemporaneous seismic networks, each with a distinctive array geometry and station spacing. Several first-order features are resolved in this phase velocity model, confirming findings from previous studies. (1) Low velocities are observed in isolated regions along the Western Rift Branch and across the Eastern Rift Branch, corresponding to areas of active volcanism. (2) Two linear low velocity zones are imaged trending southeast and southwest from the Eastern Rift Branch in Tanzania, corresponding with areas of seismic activity and indicating possible incipient rifting. (3) High velocity regions are observed beneath both the Tanzania Craton and the Bangweulu Block. Furthermore, this model indicates several new findings. (1) High velocities beneath the Bangweulu Block extend to longer periods than those found beneath the Tanzania Craton, perhaps indicating that rifting processes have not altered the Bangweulu Block as extensively as the Tanzania Craton. (2) At long periods, the fast velocities beneath the Bangweulu Block extend eastwards beyond the surficial boundaries, to and possibly across the Malawi Rift. This may suggest the presence of older, thick blocks of lithosphere in regions where they are not exposed at the surface. (3) Finally, while the findings of this study correspond well with previous studies in regions of overlapping

Hydrogeologic setting and ground water flow beneath a section of Indian River Bay, Delaware

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Krantz, David E.; Manheim, Frank T.; Bratton, John F.; Phelan, Daniel J.

2004-01-01

The small bays along the Atlantic coast of the Delmarva Peninsula (Delaware, Maryland, and Virginia) are a valuable natural resource, and an asset for commerce and recreation. These coastal bays also are vulnerable to eutrophication from the input of excess nutrients derived from agriculture and other human activities in the watersheds. Ground water discharge may be an appreciable source of fresh water and a transport pathway for nutrients entering the bays. This paper presents results from an investigation of the physical properties of the surficial aquifer and the processes associated with ground water flow beneath Indian River Bay, Delaware. A key aspect of the project was the deployment of a new technology, streaming horizontal resistivity, to map the subsurface distribution of fresh and saline ground water beneath the bay. The resistivity profiles showed complex patterns of ground water flow, modes of mixing, and submarine ground water discharge. Cores, gamma and electromagnetic-induction logs, and in situ ground water samples collected during a coring operation in Indian River Bay verified the interpretation of the resistivity profiles. The shore-parallel resistivity lines show subsurface zones of fresh ground water alternating with zones dominated by the flow of salt water from the estuary down into the aquifer. Advective flow produces plumes of fresh ground water 400 to 600 m wide and 20 m thick that may extend more than 1 km beneath the estuary. Zones of dispersive mixing between fresh and saline ground water develop on the upper, lower, and lateral boundaries of the the plume. the plumes generally underlie small incised valleys that can be traced landward to stream draining the upland. The incised valleys are filled with 1 to 2 m of silt and peat that act as a semiconfining layer to restrict the downward flow of salt water from the estuary. Active circulation of both the fresh and saline ground water masses beneath the bay is inferred from the geophysical

Upper mantle seismic velocity anomaly beneath southern Taiwan as revealed by teleseismic relative arrival times

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Chen, Po-Fei; Huang, Bor-Shouh; Chiao, Ling-Yun

2011-01-01

Probing the lateral heterogeneity of the upper mantle seismic velocity structure beneath southern and central Taiwan is critical to understanding the local tectonics and orogeny. A linear broadband array that transects southern Taiwan, together with carefully selected teleseismic sources with the right azimuth provides useful constraints. They are capable of differentiating the lateral heterogeneity along the profile with systematic coverage of ray paths. We implement a scheme based on the genetic algorithm to simultaneously determine the relative delayed times of the teleseismic first arrivals of array data. The resulting patterns of the delayed times systematically vary as a function of the incident angle. Ray tracing attributes the observed variations to a high velocity anomaly dipping east in the mantle beneath the southeast of Taiwan. Combining the ray tracing analysis and a pseudo-spectral method to solve the 2-D wave propagations, we determine the extent of the anomaly that best fits the observations via the forward grid search. The east-dipping fast anomaly in the upper mantle beneath the southeast of Taiwan agrees with the results from several previous studies and indicates that the nature of the local ongoing arc-continent collision is likely characterized by the thin-skinned style.

OPERATION ODESSA: THE FLIGHT OF NAZI WAR CRIMINALS TO LATIN AMERICA AFTER WORLD WAR II AND THE NAZI HUNTERS

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Marcos Eduardo Meinerz

2013-06-01

Full Text Available This article aims to analyze why Latin America, especially Argentina, was the region of the world that harbored the most Nazi war criminals—for example, Josef Mengele, Adolf Eichmann and Klaus Barbie—after World War II. It also aims to analyze how this fact has set the tone for the appearance of literary works about the fantastic adventures of “Nazi hunters” seeking the whereabouts of those individuals. For this purpose, in the first part of the article we will address Nazis’ escape to Latin America. Next, we analyze some literary works by authors who called themselves Nazi hunters.

Constraining P-wave velocity variations in the upper mantle beneath Southeast Asia

NARCIS (Netherlands)

Li, Chang; Hilst, R.D. van der; Toksöz, M. Nafi

2006-01-01

We have produced a P-wave model of the upper mantle beneath Southeast (SE) Asia from reprocessed short period International Seismological Centre (ISC) P and pP data, short period P data of the Annual Bulletin of Chinese Earthquakes (ABCE), and long period PP-P data.We used 3D sensitivity kernels

Tree-centered spot firing - a technique for prescribed burning beneath standing trees.

Science.gov (United States)

C. Phillip Weatherspoon; George A. Almond; Carl N. Skinner

1989-01-01

Prescribed burning beneath standing trees normally requires efforts to protect residual trees from excessive fire damage. Damage to both crowns and boles is strongly influenced by flame length, a fire characteristic functionally related to fireline intensity (Albini 1976). In a good prescribed burn, therefore, the prescription specifies desired or maximum flame lengths...

Lower-mantle plume beneath the Yellowstone hotspot revealed by core waves

Science.gov (United States)

Nelson, Peter L.; Grand, Stephen P.

2018-04-01

The Yellowstone hotspot, located in North America, is an intraplate source of magmatism the cause of which is hotly debated. Some argue that a deep mantle plume sourced at the base of the mantle supplies the heat beneath Yellowstone, whereas others claim shallower subduction or lithospheric-related processes can explain the anomalous magmatism. Here we present a shear wave tomography model for the deep mantle beneath the western United States that was made using the travel times of core waves recorded by the dense USArray seismic network. The model reveals a single narrow, cylindrically shaped slow anomaly, approximately 350 km in diameter that we interpret as a whole-mantle plume. The anomaly is tilted to the northeast and extends from the core-mantle boundary to the surficial position of the Yellowstone hotspot. The structure gradually decreases in strength from the deepest mantle towards the surface and if it is purely a thermal anomaly this implies an initial excess temperature of 650 to 850 °C. Our results strongly support a deep origin for the Yellowstone hotspot, and also provide evidence for the existence of thin thermal mantle plumes that are currently beyond the resolution of global tomography models.

Nature and extent of lava-flow aquifers beneath Pahute Mesa, Nevada Test Site

Energy Technology Data Exchange (ETDEWEB)

Prothro, L.B.; Drellack, S.L. Jr.

1997-09-01

Work is currently underway within the Underground Test Area subproject of the US Department of Energy/Nevada Operations Office Environmental Restoration Program to develop corrective action plans in support of the overall corrective action strategy for the Nevada Test Site as established in the Federal Facility Agreement and Consent Order (FFACO, 1996). A closure plan is currently being developed for Pahute Mesa, which has been identified in the FFACO as consisting of the Western and Central Pahute Mesa Corrective Action Units. Part of this effort requires that hydrogeologic data be compiled for inclusion in a regional model that will be used to predict a contaminant boundary for these Corrective Action Units. Hydrogeologic maps have been prepared for use in the model to define the nature and extent of aquifers and confining units that might influence the flow of contaminated groundwater from underground nuclear tests conducted at Pahute Mesa. Much of the groundwater flow beneath Pahute Mesa occurs within lava-flow aquifers. An understanding of the distribution and hydraulic character of these important hydrogeologic units is necessary to accurately model groundwater flow beneath Pahute Mesa. This report summarizes the results of a study by Bechtel Nevada geologists to better define the hydrogeology of lava-flow aquifers at Pahute Mesa. The purpose of this study was twofold: (1) aid in the development of the hydrostratigraphic framework for Pahute Mesa, and (2) provide information on the distribution and hydraulic character of lava-flow aquifers beneath Pahute Mesa for more accurate computer modeling of the Western and Central Pahute Mesa Corrective Action Units.

Barley (Hordeum vulgare) in the Okhotsk culture (5th-10th century AD) of northern Japan and the role of cultivated plants in hunter-gatherer economies.

Science.gov (United States)

Leipe, Christian; Sergusheva, Elena A; Müller, Stefanie; Spengler, Robert N; Goslar, Tomasz; Kato, Hirofumi; Wagner, Mayke; Weber, Andrzej W; Tarasov, Pavel E

2017-01-01

This paper discusses archaeobotanical remains of naked barley recovered from the Okhotsk cultural layers of the Hamanaka 2 archaeological site on Rebun Island, northern Japan. Calibrated ages (68% confidence interval) of the directly dated barley remains suggest that the crop was used at the site ca. 440-890 cal yr AD. Together with the finds from the Oumu site (north-eastern Hokkaido Island), the recovered seed assemblage marks the oldest well-documented evidence for the use of barley in the Hokkaido Region. The archaeobotanical data together with the results of a detailed pollen analysis of contemporaneous sediment layers from the bottom of nearby Lake Kushu point to low-level food production, including cultivation of barley and possible management of wild plants that complemented a wide range of foods derived from hunting, fishing, and gathering. This qualifies the people of the Okhotsk culture as one element of the long-term and spatially broader Holocene hunter-gatherer cultural complex (including also Jomon, Epi-Jomon, Satsumon, and Ainu cultures) of the Japanese archipelago, which may be placed somewhere between the traditionally accepted boundaries between foraging and agriculture. To our knowledge, the archaeobotanical assemblages from the Hokkaido Okhotsk culture sites highlight the north-eastern limit of prehistoric barley dispersal. Seed morphological characteristics identify two different barley phenotypes in the Hokkaido Region. One compact type (naked barley) associated with the Okhotsk culture and a less compact type (hulled barley) associated with Early-Middle Satsumon culture sites. This supports earlier suggestions that the "Satsumon type" barley was likely propagated by the expansion of the Yayoi culture via south-western Japan, while the "Okhotsk type" spread from the continental Russian Far East region, across the Sea of Japan. After the two phenotypes were independently introduced to Hokkaido, the boundary between both barley domains possibly

Barley (Hordeum vulgare in the Okhotsk culture (5th-10th century AD of northern Japan and the role of cultivated plants in hunter-gatherer economies.

Directory of Open Access Journals (Sweden)

Christian Leipe

Full Text Available This paper discusses archaeobotanical remains of naked barley recovered from the Okhotsk cultural layers of the Hamanaka 2 archaeological site on Rebun Island, northern Japan. Calibrated ages (68% confidence interval of the directly dated barley remains suggest that the crop was used at the site ca. 440-890 cal yr AD. Together with the finds from the Oumu site (north-eastern Hokkaido Island, the recovered seed assemblage marks the oldest well-documented evidence for the use of barley in the Hokkaido Region. The archaeobotanical data together with the results of a detailed pollen analysis of contemporaneous sediment layers from the bottom of nearby Lake Kushu point to low-level food production, including cultivation of barley and possible management of wild plants that complemented a wide range of foods derived from hunting, fishing, and gathering. This qualifies the people of the Okhotsk culture as one element of the long-term and spatially broader Holocene hunter-gatherer cultural complex (including also Jomon, Epi-Jomon, Satsumon, and Ainu cultures of the Japanese archipelago, which may be placed somewhere between the traditionally accepted boundaries between foraging and agriculture. To our knowledge, the archaeobotanical assemblages from the Hokkaido Okhotsk culture sites highlight the north-eastern limit of prehistoric barley dispersal. Seed morphological characteristics identify two different barley phenotypes in the Hokkaido Region. One compact type (naked barley associated with the Okhotsk culture and a less compact type (hulled barley associated with Early-Middle Satsumon culture sites. This supports earlier suggestions that the "Satsumon type" barley was likely propagated by the expansion of the Yayoi culture via south-western Japan, while the "Okhotsk type" spread from the continental Russian Far East region, across the Sea of Japan. After the two phenotypes were independently introduced to Hokkaido, the boundary between both barley

Mantle transition zone beneath northeast China from P-receiver function

Science.gov (United States)

Zhang, R.; Wu, Q.

2015-12-01

We used receiver functions to examine lateral topographical variations on the 410- and 660-km beneath northeast China and particularly the Kuril-Japan arc junctions. Compared to other receiver functions studies, our analysis was based on greater station coverage of higher density by combining all recent seismic arrays so far deployed in northeast China. Our image shows that the 410-km is featured by a ~10-20 km uplift extending in the NNE direction beneath some areas of the Quaternary basaltic rocks distributed at Abaga and at Wudalianchi. The Clapeyron slope of the olivine phase transiton at 410-km suggests that the uplift is compatible with a negative thermal anomaly. We also confirm a significant depression of the 660 from the Changbai volcanism in the north to Korea in the south along the NW-SE direction. The depression is also accompanied by an uplift of the 660 to the west. The shallow 660-km discontinuity is also particularly detected beneath the Kuril-Japan arc junctions, while it was not detected before. The thermal anomaly at 410 km depth is most likely a remnant of a detached mantle lithosphere that recently sank to depth, thus providing robust evidence for the source and evolution of these basalts. The depression of the 660-km discontinuity may support that the subducting Pacific slab bends sharply and becomes stagnant when it meets strong resistance at a depth of about 670 km. After accumulation to a great extent the stagnant slab finally penetrates into the lower mantle. Combined with the previous triplicated studies, the shallow 660-km may suggest that descending Pacific slab at its leading and junction edges might be accommodated by a tearing near a depth of 660 km. Acknowledgements. Two liner seismic arrays were deployed by the Institute of Geophysics, China Earthquake Administration. The data of the permanent stations were provided by the Data Management Centre of China, National Seismic Network at the Institute of Geophysics, China Earthquake

Slab melting and magma formation beneath the southern Cascade arc

Science.gov (United States)

Walowski, Kristina J.; Wallace, Paul J.; Clynne, Michael A.; Rasmussen, D.J.; Weis, D.

2016-01-01

The processes that drive magma formation beneath the Cascade arc and other warm-slab subduction zones have been debated because young oceanic crust is predicted to largely dehydrate beneath the forearc during subduction. In addition, geochemical variability along strike in the Cascades has led to contrasting interpretations about the role of volatiles in magma generation. Here, we focus on the Lassen segment of the Cascade arc, where previous work has demonstrated across-arc geochemical variations related to subduction enrichment, and H-isotope data suggest that H2O in basaltic magmas is derived from the final breakdown of chlorite in the mantle portion of the slab. We use naturally glassy, olivine-hosted melt inclusions (MI) from the tephra deposits of eight primitive (MgO>7 wt%) basaltic cinder cones to quantify the pre-eruptive volatile contents of mantle-derived melts in this region. The melt inclusions have B concentrations and isotope ratios that are similar to mid-ocean ridge basalt (MORB), suggesting extensive dehydration of the downgoing plate prior to reaching sub-arc depths and little input of slab-derived B into the mantle wedge. However, correlations of volatile and trace element ratios (H2O/Ce, Cl/Nb, Sr/Nd) in the melt inclusions demonstrate that geochemical variability is the result of variable addition of a hydrous subduction component to the mantle wedge. Furthermore, correlations between subduction component tracers and radiogenic isotope ratios show that the subduction component has less radiogenic Sr and Pb than the Lassen sub-arc mantle, which can be explained by melting of subducted Gorda MORB beneath the arc. Agreement between pMELTS melting models and melt inclusion volatile, major, and trace element data suggests that hydrous slab melt addition to the mantle wedge can produce the range in primitive compositions erupted in the Lassen region. Our results provide further evidence that chlorite-derived fluids from the mantle portion of the

What's Cooler Than Being Cool? Icefin: Robotic Exploration Beneath Antarctic Ice Shelves

Science.gov (United States)

Lawrence, J.; Schmidt, B. E.; Meister, M. R.; Glass, J. B.; Bowman, J. S.; Stockton, A. M.; Dichek, D.; Hurwitz, B.; Ramey, C.; Spears, A.; Walker, C. C.

2017-12-01

The 2017-18 Antarctic field season marks the first of three under the RISEUP project (Ross Ice Shelf & Europa Underwater Probe, NASA PSTAR program grant NNX16AL07G, PI B. E. Schmidt). RISEUP expands our efforts to understand the physical processes governing ice-ocean interactions from beneath the McMurdo Ice Shelf (MIS) to the Ross Ice Shelf (RIS), utilizing the modular autonomous or remotely operable submersible vehicle (AUV/ROV) Icefin. The remote, aphotic regions below Antarctic shelves present a unique opportunity- they are both poorly understood terrestrial environments and analogs for similar systems hypothesized to be present on other bodies in our solar system, such as Europa and Enceladus. By developing new robotic technologies to access and explore ice shelf cavities we are advancing our understanding of how temperature, pressure, and salinity influence the ice-ocean interface, the limits of habitable environments on Earth, and what biological processes and adaptations enable the life discovered by the RISP and WISSARD programs during initial exploration beneath the RIS. These investigations further our understanding of ocean world habitability and support planned and proposed planetary missions (e.g. Europa Clipper, Europa Lander) via improved constraint of marine ice accretion processes, organic entrainment, and interface habitability. Custom built at Georgia Tech and first deployed during the 2014/15 Antarctic season, Icefin is 3.5 m, 125 kg modular vehicle that now carries a full suite of oceanographic sensors (including conductivity, temperature, depth, dissolved O2, dissolved organic matter, turbidity, pH, eH, and sonar) that can be deployed through boreholes as small as 25 cm in diameter. Here we present continued analysis of basal ice and oceanographic observations in the McMurdo Sound region from 2012-2015 with, pending anticipated field work, comparisons to preliminary data from the 2017/18 field season beneath both the McMurdo and Ross Ice

Efficacy evaluation of laparoscopy assisted ultrasound guided radiofrequency ablation in the treatment of hepatocellular carcinoma beneath the diaphragm

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Song WANG

2017-06-01

Full Text Available Objective To explore the feasibility, safety and efficacy of laparoscopy assisted ultrasound guided radiofrequency ablation (RFA in the treatment of hepatocellular carcinoma (HCC beneath the diaphragm. Methods Twenty- three consecutive patients with solitary HCC beneath the diaphragm were treated by laparoscopy assisted ultrasound guided RFA in the Chinese PLA General Hospital from January 2013 to March 2016. We observed the perioperative complications and followed- up long-term effect. Results All the 23 patients successfully underwent laparoscopy assisted ultrasound guided radiofrequency ablation. No serious complications such as massive hemorrhage, biliary fistula and severe pleural effusion, hemopneumothorax occurred in the patients during perioperative period. CT examination 2-3 days after the operation revealed that the tumor was completely covered by the ablation area. Besides, the survival condition was satisfactory during follow-up period of 9-38 months. Conclusion Laparoscopy-assisted ultrasound-guided radiofrequency ablation is effective and safe for HCC beneath the diaphragm. DOI: 10.11855/j.issn.0577-7402.2017.05.16

The Lithosphere-asthenosphere Boundary beneath the South Island of New Zealand

Science.gov (United States)

Hua, J.; Fischer, K. M.; Savage, M. K.

2017-12-01

Lithosphere-asthenosphere boundary (LAB) properties beneath the South Island of New Zealand have been imaged by Sp receiver function common-conversion point stacking. In this transpressional boundary between the Australian and Pacific plates, dextral offset on the Alpine fault and convergence have occurred for the past 20 My, with the Alpine fault now bounded by Australian plate subduction to the south and Pacific plate subduction to the north. This study takes advantage of the long-duration and high-density seismometer networks deployed on or near the South Island, especially 29 broadband stations of the New Zealand permanent seismic network (GeoNet). We obtained 24,980 individual receiver functions by extended-time multi-taper deconvolution, mapping to three-dimensional space using a Fresnel zone approximation. Pervasive strong positive Sp phases are observed in the LAB depth range indicated by surface wave tomography (Ball et al., 2015) and geochemical studies. These phases are interpreted as conversions from a velocity decrease across the LAB. In the central South Island, the LAB is observed to be deeper and broader to the west of the Alpine fault. The deeper LAB to the west of the Alpine fault is consistent with oceanic lithosphere attached to the Australian plate that was partially subducted while also translating parallel to the Alpine fault (e.g. Sutherland, 2000). However, models in which the Pacific lithosphere has been underthrust to the west past the Alpine fault cannot be ruled out. Further north, a zone of thin lithosphere with a strong and vertically localized LAB velocity gradient occurs to the west of the fault, juxtaposed against a region of anomalously weak LAB conversions to the east of the fault. This structure, similar to results of Sp imaging beneath the central segment of the San Andreas fault (Ford et al., 2014), also suggests that lithospheric blocks with contrasting LAB properties meet beneath the Alpine fault. The observed variations in

Paraoxonases: ancient substrate hunters and their evolving role in ischemic heart disease.

Science.gov (United States)

Martinelli, Nicola; Consoli, Letizia; Girelli, Domenico; Grison, Elisa; Corrocher, Roberto; Olivieri, Oliviero

2013-01-01

Interest in the role of paraoxonases (PON) in cardiovascular research has increased substantially over the past two decades. These multifaceted and pleiotropic enzymes are encoded by three highly conserved genes (PON1, PON2, and PON3) located on chromosome 7q21.3-22.1. Phylogenetic analysis suggests that PON2 is the ancient gene from which PON1 and PON3 arose via gene duplication. Although PON are primarily lactonases with overlapping, but distinct specificities, their physiologic substrates remain poorly characterized. The most interesting characteristic of PON, however, is their multifunctional roles in various biochemical pathways. These include protection against oxidative damage and lipid peroxidation, contribution to innate immunity, detoxification of reactive molecules, bioactivation of drugs, modulation of endoplasmic reticulum stress, and regulation of cell proliferation/apoptosis. In general, PON appear as "hunters" of old and new substrates often involved in athero- and thrombogenesis. Although reduced PON activity appears associated with increased cardiovascular risk, the correlation between PON genotype and ischemic heart disease remains controversial. In this review, we examine the biochemical pathways impacted by these unique enzymes and investigate the potential use of PON as diagnostic tools and their impact on development of future therapeutic strategies.

Topography of upper mantle seismic discontinuities beneath the North Atlantic: the Azores, Canary and Cape Verde plumes

Science.gov (United States)

Saki, Morvarid; Thomas, Christine; Nippress, Stuart E. J.; Lessing, Stephan

2015-04-01

We are mapping the topography of upper mantle seismic discontinuities beneath the North Atlantic and surrounding regions by using precursor arrivals to PP and SS seismic waves that reflect off the seismic discontinuities. Many source-receiver combinations have been used in order to collect a large dataset of reflection points beneath our investigating area. We analyzed over 1700 seismograms from MW>5.8 events using array seismic methods to enhance the signal to noise ratio. The measured time lag between PP (SS) arrivals and their corresponding precursors on robust stacks are used to measure the depth of the transition zone boundaries. The reflectors' depths show a correlation between the location of hotspots and a significantly depressed 410 km discontinuity indicating a temperature increase of 200-300 K compared to the surrounding mantle. For the 660 km discontinuity three distinct behaviours are visible: i) normal depths beneath Greenland and at a distance of a few hundred kilometres away from the hotspots and ii) shallower 660 km discontinuity compared with the global average value near hotspots closer to the Mid-Atlantic Ridge and iii) very few observations of a 660 km discontinuity at the hotspot locations. We interpret our observations as a large upwelling beneath the southern parts of our study region, possibly due to the South Atlantic convection cell. The thermal anomaly may be blocked by endothermic phase transformation and likely does not extend through the top of the transition zone as whole except for those branches which appear as the Azores, Canaries and Cape Verde hotspots at the surface.

The Implications of Victimhood Identity: The Case of ‘Persecution’ of Swedish Hunters

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Erica von Essen

2017-06-01

Full Text Available This ethnographically based study examines Swedish hunters’ claims to victimhood through appeal to the term ‘persecution’. Perceiving disenfranchisement, injustice and discrimination on the basis of wolf conservation policy, we present hunters’ self-styled predicament as victimhood-claimants of persecution at the hands of a state that has been co-opted by a conservationist, pro-wolf agenda that systematically disenfranchises rural and hunting interests and lifestyles. Through the phenomenological accounts of hunter respondents, our paper takes seriously the hunters’ perception of persecution and, likewise, considers the opposite case made by conservationists: that wolves have been, and continue to be, the real victims of persecution in the conflict. Nonetheless, we show that the persecution language as it is applied from opposing parties in the conflict is problematic inasmuch as it is focused around creating a moral panic and confusion among the Swedish public who are ultimately responsible, as a democratic body-politic, for assessing the legitimacy of claims to moral wrong-doing and legal redress for the wronged. Our case study joins scholarship that explores the pathologies of claims to victimization

Seismic characterization of a `compound tectonic wedge` beneath the Rocky Mountain foreland basin, Alberta

Energy Technology Data Exchange (ETDEWEB)

Lawton, D. C.; Sukaramongkol, C.; Spratt, D. A. [Calgary Univ., AB (Canada). Dept. of Geology and Geophysics

1996-06-01

The detailed internal geometry of a `compound tectonic wedge` beneath an eastward-dipping homocline in the Sundre area of southern Alberta was described. Data for the description was obtained by interpreting reflection seismic data. The wedge has been driven into the foreland succession beneath the gently dipping upper detachment which occurs within coal horizons of the Upper Brazeau Group. Shape of the upper detachment near its toe indicates that rocks in its hanging wall were decoupled from strain associated with forward emplacement of the wedge. Folding of the upper detachment occurs in the hinterland region of the wedge, with a new upper detachment developing above the fold. Emplacement of the wedge is suspected to be the result of excess pore fluid pressure, although proof of this happening awaits quantification of the mechanical model. 25 refs., 8 figs.

Channelization of plumes beneath ice shelves

KAUST Repository

Dallaston, M.  C.; Hewitt, I. J.; Wells, A. J.

2015-01-01

© 2015 Cambridge University Press. We study a simplified model of ice-ocean interaction beneath a floating ice shelf, and investigate the possibility for channels to form in the ice shelf base due to spatial variations in conditions at the grounding line. The model combines an extensional thin-film description of viscous ice flow in the shelf, with melting at its base driven by a turbulent ocean plume. Small transverse perturbations to the one-dimensional steady state are considered, driven either by ice thickness or subglacial discharge variations across the grounding line. Either forcing leads to the growth of channels downstream, with melting driven by locally enhanced ocean velocities, and thus heat transfer. Narrow channels are smoothed out due to turbulent mixing in the ocean plume, leading to a preferred wavelength for channel growth. In the absence of perturbations at the grounding line, linear stability analysis suggests that the one-dimensional state is stable to initial perturbations, chiefly due to the background ice advection.

Channelization of plumes beneath ice shelves

KAUST Repository

Dallaston, M. C.

2015-11-11

© 2015 Cambridge University Press. We study a simplified model of ice-ocean interaction beneath a floating ice shelf, and investigate the possibility for channels to form in the ice shelf base due to spatial variations in conditions at the grounding line. The model combines an extensional thin-film description of viscous ice flow in the shelf, with melting at its base driven by a turbulent ocean plume. Small transverse perturbations to the one-dimensional steady state are considered, driven either by ice thickness or subglacial discharge variations across the grounding line. Either forcing leads to the growth of channels downstream, with melting driven by locally enhanced ocean velocities, and thus heat transfer. Narrow channels are smoothed out due to turbulent mixing in the ocean plume, leading to a preferred wavelength for channel growth. In the absence of perturbations at the grounding line, linear stability analysis suggests that the one-dimensional state is stable to initial perturbations, chiefly due to the background ice advection.

Diagnosis of tuberculosis in the wild boar (Sus scrofa: a comparison of methods applicable to hunter-harvested animals.

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Nuno Santos

Full Text Available BACKGROUND: To obtain robust epidemiological information regarding tuberculosis (TB in wildlife species, appropriate diagnostic methods need to be used. Wild boar (Sus scrofa recently emerged as a major maintenance host for TB in some European countries. Nevertheless, no data is available to evaluate TB post-mortem diagnostic methods in hunter-harvested wild boar. METHODOLOGY/PRINCIPAL FINDINGS: Six different diagnostic methods for TB were evaluated in parallel in 167 hunter-harvested wild boar. Compared to bacteriological culture, estimates of sensitivity of histopathology was 77.8%, gross pathology 72.2%, PCR for the MPB70 gene 66.7%, detection of acid-fast bacilli (AFB in tissue contact smears 55.6% and in histopathology slides 16.7% (estimated specificity was 96.7%, 100%, 100%, 94.4% and 100%, respectively. Combining gross pathology with stained smears in parallel increased estimated sensitivity to 94.4% (94.4% specificity. Four probable bacteriological culture false-negative animals were identified by Discriminant Function Analysis. Recalculating the parameters considering these animals as infected generated estimated values for sensitivity of bacteriology and histopathology of 81.8%, gross pathology 72.7%, PCR for the MPB70 gene 63.6%, detection of AFB in tissue contact smears 54.5% and in histopathology slides 13.6% (estimated specificity was 100% for gross pathology, PCR, bacteriology and detection of AFB in histopathology slides, 96.7% for histopathology and 94.4% for stained smears. CONCLUSIONS/SIGNIFICANCE: These results show that surveys for TB in wild boar based exclusively on gross pathology considerably underestimate prevalence, while combination of tests in parallel much improves sensitivity and negative predictive values. This finding should thus be considered when planning future surveys and game meat inspection schemes. Although bacteriological culture is the reference test for TB diagnosis, it can generate false

Magma heating by decompression-driven crystallization beneath andesite volcanoes.

Science.gov (United States)

Blundy, Jon; Cashman, Kathy; Humphreys, Madeleine

2006-09-07

Explosive volcanic eruptions are driven by exsolution of H2O-rich vapour from silicic magma. Eruption dynamics involve a complex interplay between nucleation and growth of vapour bubbles and crystallization, generating highly nonlinear variation in the physical properties of magma as it ascends beneath a volcano. This makes explosive volcanism difficult to model and, ultimately, to predict. A key unknown is the temperature variation in magma rising through the sub-volcanic system, as it loses gas and crystallizes en route. Thermodynamic modelling of magma that degasses, but does not crystallize, indicates that both cooling and heating are possible. Hitherto it has not been possible to evaluate such alternatives because of the difficulty of tracking temperature variations in moving magma several kilometres below the surface. Here we extend recent work on glassy melt inclusions trapped in plagioclase crystals to develop a method for tracking pressure-temperature-crystallinity paths in magma beneath two active andesite volcanoes. We use dissolved H2O in melt inclusions to constrain the pressure of H2O at the time an inclusion became sealed, incompatible trace element concentrations to calculate the corresponding magma crystallinity and plagioclase-melt geothermometry to determine the temperature. These data are allied to ilmenite-magnetite geothermometry to show that the temperature of ascending magma increases by up to 100 degrees C, owing to the release of latent heat of crystallization. This heating can account for several common textural features of andesitic magmas, which might otherwise be erroneously attributed to pre-eruptive magma mixing.

Sampling and Hydrogeology of the Vadose Zone Beneath the 300 Area Process Ponds

International Nuclear Information System (INIS)

Bjornstad, Bruce N.

2004-01-01

Four open pits were dug with a backhoe into the vadose zone beneath the former 300 Area Process Ponds in April 2003. Samples were collected about every 2 feet for physical, chemical, and/or microbiological characterization. This reports presents a stratigraphic and geohydrologic summary of the four excavations

Fate of effluent-borne contaminants beneath septic tank drainfields overlying a Karst aquifer.

Science.gov (United States)

Katz, Brian G; Griffin, Dale W; McMahon, Peter B; Harden, Harmon S; Wade, Edgar; Hicks, Richard W; Chanton, Jeffrey P

2010-01-01

Groundwater quality effects from septic tanks were investigated in the Woodville Karst Plain, an area that contains numerous sinkholes and a thin veneer of sands and clays overlying the Upper Floridan aquifer (UFA). Concerns have emerged about elevated nitrate concentrations in the UFA, which is the source of water supply in this area of northern Florida. At three sites during dry and wet periods in 2007-2008, water samples were collected from the septic tank, shallow and deep lysimeters, and drainfield and background wells in the UFA and analyzed for multiple chemical indicators including nutrients, nitrate isotopes, organic wastewater compounds (OWCs), pharmaceutical compounds, and microbiological indicators (bacteria and viruses). Median NO3-N concentration in groundwater beneath the septic tank drainfields was 20 mg L(-1) (8.0-26 mg L(-1)). After adjusting for dilution, about 25 to 40% N loss (from denitrification, ammonium sorption, and ammonia volatilization) occurs as septic tank effluent moves through the unsaturated zone to the water table. Nitrogen loading rates to groundwater were highly variable at each site (3.9-12 kg N yr(-1)), as were N and chloride depth profiles in the unsaturated zone. Most OWCs and pharmaceutical compounds were highly attenuated beneath the drainfields; however, five Cs (caffeine, 1,7-dimethylxanthine, phenol, galaxolide, and tris(dichloroisotopropyl)phosphate) and two pharmaceutical compounds (acetaminophen and sulfamethoxazole) were detected in groundwater samples. Indicator bacteria and human enteric viruses were detected in septic tank effluent samples but only intermittently in soil water and groundwater. Contaminant movement to groundwater beneath each septic tank system also was related to water use and differences in lithology at each site.

Magnetotelluric investigations of the lithosphere beneath the central Rae craton, mainland Nunavut, Canada

Science.gov (United States)

Spratt, Jessica E.; Skulski, Thomas; Craven, James A.; Jones, Alan G.; Snyder, David B.; Kiyan, Duygu

2014-03-01

New magnetotelluric soundings at 64 locations throughout the central Rae craton on mainland Nunavut constrain 2-D resistivity models of the crust and lithospheric mantle beneath three regional transects. Responses determined from colocated broadband and long-period magnetotelluric recording instruments enabled resistivity imaging to depths of > 300 km. Strike analysis and distortion decomposition on all data reveal a regional trend of 45-53°, but locally the geoelectric strike angle varies laterally and with depth. The 2-D models reveal a resistive upper crust to depths of 15-35 km that is underlain by a conductive layer that appears to be discontinuous at or near major mapped geological boundaries. Surface projections of the conductive layer coincide with areas of high grade, Archean metasedimentary rocks. Tectonic burial of these rocks and thickening of the crust occurred during the Paleoproterozoic Arrowsmith (2.3 Ga) and Trans-Hudson orogenies (1.85 Ga). Overall, the uppermost mantle of the Rae craton shows resistivity values that range from 3000 Ω m in the northeast (beneath Baffin Island and the Melville Peninsula) to 10,000 Ω m beneath the central Rae craton, to >50,000 Ω m in the south near the Hearne Domain. Near-vertical zones of reduced resistivity are identified within the uppermost mantle lithosphere that may be related to areas affected by mantle melt or metasomatism associated with emplacement of Hudsonian granites. A regional decrease in resistivities to values of 500 Ω m at depths of 180-220 km, increasing to 300 km near the southern margin of the Rae craton, is interpreted as the lithosphere-asthenosphere boundary.

Shear wave velocity model beneath CBJI station West Java, Indonesia from joint inversion of teleseismic receiver functions and surface wave dispersion

Science.gov (United States)

Simanungkalit, R. H.; Anggono, T.; Syuhada; Amran, A.; Supriyanto

2018-03-01

Earthquake signal observations around the world allow seismologists to obtain the information of internal structure of the Earth especially the Earth’s crust. In this study, we used joint inversion of receiver functions and surface wave group velocities to investigate crustal structure beneath CBJI station in West Java, Indonesia. Receiver function were calculated from earthquakes with magnitude more than 5 and at distance 30°-90°. Surface wave group velocities were calculated using frequency time analysis from earthquakes at distance of 30°- 40°. We inverted shear wave velocity model beneath the station by conducting joint inversion from receiver functions and surface wave dispersions. We suggest that the crustal thickness beneath CBJI station, West Java, Indonesia is about 35 km.

Improved quality of beneath-canopy grass in South African savannas: Local and seasonal variation

NARCIS (Netherlands)

Treydte, A.C.; Looringh van Beeck, F.A.; Ludwig, F.; Heitkonig, I.M.A.

2008-01-01

Questions: Do large trees improve the nutrient content and the structure of the grass layer in savannas? Does the magnitude of this improvement differ with locality ( soil nutrients) and season ( water availability)? Are grass structure and species composition beneath tree canopies influenced by

Seismological Imaging of Melt Production Regions Beneath the Backarc Spreading Center and Volcanic Arc, Mariana Islands

Science.gov (United States)

Wiens, Douglas; Pozgay, Sara; Barklage, Mitchell; Pyle, Moira; Shiobara, Hajime; Sugioka, Hiroko

2010-05-01

We image the seismic velocity and attenuation structure of the mantle melt production regions associated with the Mariana Backarc Spreading Center and Mariana Volcanic Arc using data from the Mariana Subduction Factory Imaging Experiment. The passive component of this experiment consisted of 20 broadband seismographs deployed on the island chain and 58 ocean-bottom seismographs from June, 2003 until April, 2004. We obtained the 3D P and S wave velocity structure of the Mariana mantle wedge from a tomographic inversion of body wave arrivals from local earthquakes as well as P and S arrival times from large teleseismic earthquakes determined by multi-channel cross correlation. We also determine the 2-D attenuation structure of the mantle wedge using attenuation tomography based on local and regional earthquake spectra, and a broader-scale, lower resolution 3-D shear velocity structure from inversion of Rayleigh wave phase velocities using a two plane wave array analysis approach. We observe low velocity, high attenuation anomalies in the upper mantle beneath both the arc and backarc spreading center. These anomalies are separated by a higher velocity, lower attenuation region at shallow depths (< 80 km), implying distinct magma production regions for the arc and backarc in the uppermost mantle. The largest magnitude anomaly beneath the backarc spreading center is found at shallower depth (25-50 km) compared to the arc (50-100 km), consistent with melting depths estimated from the geochemistry of arc and backarc basalts (K. Kelley, pers. communication). The velocity and attenuation signature of the backarc spreading center is narrower than the corresponding anomaly found beneath the East Pacific Rise by the MELT experiment, perhaps implying a component of focused upwelling beneath the spreading center. The strong velocity and attenuation anomaly beneath the spreading center contrasts strongly with preliminary MT inversion results showing no conductivity anomaly in the

Upper mantle velocity structure beneath Italy from direct and secondary P-wave teleseismic tomography

Directory of Open Access Journals (Sweden)

P. De Gori

1997-06-01

Full Text Available High-quality teleseismic data digitally recorded by the National Seismic Network during 1988-1995 have been analysed to tomographically reconstruct the aspherical velocity structure of the upper mantle beneath the Italian region. To improve the quality and the reliability of the tomographic images, both direct (P, PKPdf and secondary (pP,sP,PcP,PP,PKPbc,PKPab travel-time data were used in the inversion. Over 7000 relative residuals were computed with respect to the IASP91 Earth velocity model and inverted using a modified version of the ACH technique. Incorporation of data of secondary phases resulted in a significant improvement of the sampling of the target volume and of the spatial resolution of the heterogeneous zones. The tomographic images show that most of the lateral variations in the velocity field are confined in the first ~250 km of depth. Strong low velocity anomalies are found beneath the Po plain, Tuscany and Eastern Sicily in the depth range between 35 and 85 km. High velocity anomalies dominate the upper mantle beneath the Central-Western Alps, Northern-Central Apennines and Southern Tyrrhenian sea at lithospheric depths between 85 and 150 km. At greater depth, positive anomalies are still observed below the northernmost part of the Apenninic chain and Southern Tyrrhenian sea. Deeper anomalies present in the 3D velocity model computed by inverting only the first arrivals dataset, generally appear less pronounced in the new tomographic reconstructions. We interpret this as the result of the ray sampling improvement on the reduction of the vertical smearing effects.

1500-year Record of trans-Pacific Dust Flux collected from the Denali Ice Core, Mt. Hunter, Alaska

Science.gov (United States)

Saylor, P. L.; Osterberg, E. C.; Koffman, B. G.; Winski, D.; Ferris, D. G.; Kreutz, K. J.; Wake, C. P.; Handley, M.; Campbell, S. W.

2016-12-01

Mineral dust aerosols are a critical component of the climate system through their influence on atmospheric radiative forcing, ocean productivity, and surface albedo. Dust aerosols derived from Asian deserts are known to reach as far as Europe through efficient transport in the upper tropospheric westerlies. While centennially-to-millennially resolved Asian dust records exist over the late Holocene from North Pacific marine sediment cores and Asian loess deposits, a high-resolution (sub-annual to decadal) record of trans-Pacific dust flux will significantly improve our understanding of North Pacific dust-climate interactions and provide paleoclimatological context for 20th century dust activity. Here we present an annually resolved 1500-year record of trans-Pacific dust transport based on chemical and physical dust measurements in parallel Alaskan ice cores (208 m to bedrock) collected from the summit plateau of Mt. Hunter in Denali National Park. The cores were sampled at high resolution using a continuous melter system with discrete analyses for major ions (Dionex ion chromatograph), trace elements (Element2 inductively coupled plasma mass spectrometer), and stable water isotope ratios (Picarro laser ringdown spectroscopy), and continuous flow analysis for dust concentration and size distribution (Klotz Abakus). We compare the ice core dust record to instrumental aerosol stations, satellite observations, and dust model data from the instrumental period, and evaluate climatic controls on dust emission and trans-Pacific transport using climate reanalysis data, to inform dust-climate relationships over the past 1500 years. Physical particulate and chemical data demonstrate remarkable fidelity at sub-annual resolution, with both displaying a strong springtime peak consistent with periods of high dust activity over Asian desert source regions. Preliminary results suggest volumetric mode typically ranges from 4.5 - 6.5 um, with a mean value of 5.5 um. Preliminary

Mitigating the health impacts of a natural disaster--the June 2007 long-weekend storm in the Hunter region of New South Wales.

Science.gov (United States)

Cretikos, Michelle A; Merritt, Tony D; Main, Kelly; Eastwood, Keith; Winn, Linda; Moran, Lucille; Durrheim, David N

A severe storm that began on Thursday, 7 June 2007 brought heavy rains and gale-force winds to Newcastle, Gosford, Wyong, Sydney, and the Hunter Valley region of New South Wales. The storm caused widespread flooding and damage to houses, businesses, schools and health care facilities, and damaged critical infrastructure. Ten people died as a result of the storm, and approximately 6000 residents were evacuated. A natural disaster was declared in 19 local government areas, with damage expected to reach $1.5 billion. Additional demands were made on clinical health services, and interruption of the electricity supply to over 200,000 homes and businesses, interruption of water and gas supplies, and sewerage system pump failures presented substantial public health threats. A public health emergency operations centre was established by the Hunter New England Area Health Service to coordinate surveillance activities, respond to acute public health issues and prevent disease outbreaks. Public health activities focused on providing advice, cooperating with emergency service agencies, monitoring water quality and availability, preventing illness from sewage-contaminated flood water, assessing environmental health risks, coordinating the local government public health response, and surveillance for storm-related illness and disease outbreaks, including gastroenteritis. The local ABC (Australian Broadcasting Corporation) radio station played a key role in disseminating public health advice. A household survey conducted within a fortnight of the storm established that household preparedness and storm warning systems could be improved.

Seismic evidence of the lithosphere-asthenosphere boundary beneath Izu-Bonin area

Science.gov (United States)

Cui, H.; Gao, Y.; Zhou, Y.

2016-12-01

The lithosphere-asthenosphere boundary (LAB), separating the rigid lithosphere and the ductile asthenosphere layers, is the seismic discontinuity with the negative velocity contrast of the Earth's interior [Fischer et al., 2010]. The LAB has been also termed the Gutenberg (G) discontinuity that defines the top of the low velocity zone in the upper mantle [Gutenberg, 1959; Revenaugh and Jordan, 1991]. The seismic velocity, viscosity, resistivity and other physical parameters change rapidly with the depths across the boundary [Eaton et al., 2009]. Seismic detections on the LAB in subduction zone regions are of great help to understand the interactions between the lithosphere and asthenosphere layers and the geodynamic processes related with the slab subductions. In this study, the vertical broadband waveforms are collected from three deep earthquake events occurring from 2000 to 2014 with the focal depths of 400 600 km beneath the Izu-Bonin area. The waveform data is processed with the linear slant stack method [Zang and Zhou, 2002] to obtain the vespagrams in the relative travel-time to slowness domain and the stacked waveforms. The sP precursors reflected on the LAB (sLABP), which have the negative polarities with the amplitude ratios of 0.17 0.21 relative to the sP phases, are successfully extracted. Based on the one-dimensional modified velocity model (IASP91-IB), we obtain the distributions for six reflected points of the sLABP phases near the source region. Our results reveal that the LAB depths range between 58 and 65 km beneath the Izu-Bonin Arc, with the average depth of 62 km and the small topography of 7 km. Compared with the results of the tectonic stable areas in Philippine Sea [Kawakatsu et al., 2009; Kumar and Kawakatsu, 2011], the oceanic lithosphere beneath the Izu-Bonin Arc shows the obvious thinning phenomena. We infer that the lithospheric thinning is closely related with the partial melting, which is caused by the volatiles continuously released

Operations Charioteer, Musketeer, Touchstone, Cornerstone, Aqueduct, Sculpin and Julin. Tests Mill Yard, Diamond Beech, Mighty Oak, Middle Note Mission Ghost, Mission Cyber, Misty Echo, Disko Elm, Mineral Quarry, Distant Zenith, Diamond Fortune, and Hunters Trophy

National Research Council Canada - National Science Library

Schoengold, Carole

1999-01-01

...; Tests MILL YARD, DIAMOND BEECH, MIGHTY OAK, MIDDLE NOTE, MISSION GHOST, MISSION CYBER, MISTY ECHO, DISKO ELM, MINERAL QUARRY, DISTANT ZENITH, DIAMOND FORTUNE, and HUNTERS TROPHY, 9 October 1985 to 18 September 1992...

The neutrino hunters the chase for the ghost particle and the secrets of the universe

CERN Document Server

Jayawardhana, Ray

2014-01-01

In Neutrino Hunters, the renowned astrophysicist and award-winning writer Ray Jayawardhana takes us on a thrilling journey into the shadowy world of neutrinos and the colorful lives of those who seek them. Demystifying particle science along the way, Jayawardhana tells a detective story with cosmic implications—interweaving tales of the sharp-witted theorist Wolfgang Pauli; the troubled genius Ettore Majorana; the harbinger of the atomic age Enrico Fermi; the notorious Cold War defector Bruno Pontecorvo; and the dynamic dream team of Marie and Pierre Curie. Then there are the scientists of today who have caught the neutrino bug, and whose experimental investigations stretch from a working nickel mine in Ontario to a long tunnel through a mountain in central Italy, from a nuclear waste site in New Mexico to a bay on the South China Sea, and from Olympic-size pools deep underground to a gigantic cube of Antarctic ice—called, naturally, IceCube. As Jayawardhana recounts a captivating saga of scientific disc...

Mantle wedge structure beneath the Yamato Basin, southern part of the Japan Sea, revealed by long-term seafloor seismic observations

Science.gov (United States)

Shinohara, M.; Nakahigashi, K.; Yamashita, Y.; Yamada, T.; Mochizuki, K.; Shiobara, H.

2016-12-01

The Japanese Islands are located at subduction zones where Philippine Sea (PHS) plate subducts from the southeast beneath the Eurasian plate and the Pacific plate descends from the east beneath the PHS and Eurasian plates and have a high density of seismic stations. Many seismic tomography studies using land seismic station data were conducted to reveal the seismic structure. These studies discussed the relationship between heterogeneous structures and the release of fluids from the subducting slab, magma generation and movement in the subduction zone. However, regional tomography using the land station data did not have a sufficient resolution to image a deep structure beneath the Japan Sea.To obtain the deep structure, observations of natural earthquakes within the Japan Sea are essential. Therefore, we started the repeating long-term seismic observations using ocean bottom seismometers(OBSs) in the Yamato Basin from 2013 to 2016. We apply travel-time tomography method to the regional earthquake and teleseismic arrival-data recorded by OBSs and land stations. In this presentation, we will report the P and S wave tomographic images down to a depth of 300 km beneath the southern part of the Japan Sea. This study was supported by "Integrated Research Project on Seismic and Tsunami Hazards around the Sea of Japan" conducted by the Ministry of Education, Culture, Sports, Science, and Technology (MEXT) of Japan.

Heterogeneous subduction structure within the Pacific plate beneath the Izu-Bonin arc

Science.gov (United States)

Gong, Wei; Xing, Junhui; Jiang, Xiaodian

2018-05-01

The Izu-Bonin subduction zone is a subduction system formed in early Eocene. The structure of the subduction zone becomes complicated with the evolution of the surrounding plate motion, and many aspects are still unkown or ambiguous. The geodynamic implications are further investigated in related to published seismic observations and geochemical characters of the Izu-Bonin subduction zone. As indicated by seismic tomography and epicentral distributions, the dip angle of the plate beneath the segment to the south of 29°-30°N (the southern Izu-Bonin) is much steeper than the northern one (the northern Izu-Bonin). Deep focus events in the southern segment extend to the depth of ∼600 km, whereas in the northern section deep events just terminate at 420-450 km. Particularly, tomographic images show an obvious boundary between the northern and southern Izu-Bonin at depths of 150-600 km neglected in the previous studies. The northern and southern segments are even separated by a wide range of low-velocity anomaly in P and S wave tomography at 380 km and 450 km depths. In this depth range, three events near 30°N are characterized by strike-slip mechanisms with slab parallel σ1 and horizontally north-south trending σ3, which differ with the typical down-dip compression mechanisms for neighboring events. These events could be attributed to an abrupt change of the morphology and movement of the slab in the transition segment between the northern and southern Izu-Bonin. Indicated by the focal mechanisms, the northern and southern Izu-Bonin exhibits an inhomogeneous stress field, which is closely related to age differences of the downgoing slab. Because of the reheating process, the thermal age of the Pacific plate entering the Izu-Bonin trench in the past 10 Ma, is only 60-90 ± 20 Ma, along with the younger plate subducting in the northern segment. The seismic anisotropy implies that mantle wedge flow orientation is between the motion direction of the Pacific plate and

Crustal structure beneath two seismic stations in the Sunda-Banda arc transition zone derived from receiver function analysis

Energy Technology Data Exchange (ETDEWEB)

Syuhada, E-mail: hadda9@gmail.com [Graduate Research on Earthquake and Active Tectonics (GREAT), Bandung Institute of Technology, Jalan Ganesha 10, Bandung 40132 (Indonesia); Research Centre for Physics - Indonesian Institute of Sciences (LIPI), Kompleks Puspiptek Serpong, Tangsel 15314, Banten Indonesia (Indonesia); Hananto, Nugroho D.; Handayani, Lina [Research Centre for Geotechnology - Indonesian Institute of Sciences (LIPI), Jl. Sangkuriang (Kompleks LIPI) Bandung 40135 (Indonesia); Puspito, Nanang T; Yudistira, Tedi [Faculty of Mining and Petroleum Engineering ITB, Jalan Ganesha 10, Bandung 40132 (Indonesia); Anggono, Titi [Research Centre for Physics - Indonesian Institute of Sciences (LIPI), Kompleks Puspiptek Serpong, Tangsel 15314, Banten Indonesia (Indonesia)

2015-04-24

We analyzed receiver functions to estimate the crustal thickness and velocity structure beneath two stations of Geofon (GE) network in the Sunda-Banda arc transition zone. The stations are located in two different tectonic regimes: Sumbawa Island (station PLAI) and Timor Island (station SOEI) representing the oceanic and continental characters, respectively. We analyzed teleseismic events of 80 earthquakes to calculate the receiver functions using the time-domain iterative deconvolution technique. We employed 2D grid search (H-κ) algorithm based on the Moho interaction phases to estimate crustal thickness and Vp/Vs ratio. We also derived the S-wave velocity variation with depth beneath both stations by inverting the receiver functions. We obtained that beneath station PLAI the crustal thickness is about 27.8 km with Vp/Vs ratio 2.01. As station SOEI is covered by very thick low-velocity sediment causing unstable solution for the inversion, we modified the initial velocity model by adding the sediment thickness estimated using high frequency content of receiver functions in H-κ stacking process. We obtained the crustal thickness is about 37 km with VP/Vs ratio 2.2 beneath station SOEI. We suggest that the high Vp/Vs in station PLAI may indicate the presence of fluid ascending from the subducted plate to the volcanic arc, whereas the high Vp/Vs in station SOEI could be due to the presence of sediment and rich mafic composition in the upper crust and possibly related to the serpentinization process in the lower crust. We also suggest that the difference in velocity models and crustal thicknesses between stations PLAI and SOEI are consistent with their contrasting tectonic environments.

Lithospheric Layering beneath the Contiguous United States Constrained by S-to-P Receiver Functions

Science.gov (United States)

Liu, L.; Liu, K. H.; Kong, F.; Gao, S. S.

2017-12-01

The greatly-improved spatial coverage of broadband seismic stations as a result of the deployment of the EarthScope Transportable Array (TA) stations and the diversity of tectonic environments in the contiguous United States provide a unique opportunity to investigate the depth variation and nature of intra-lithospheric interfaces in different tectonic regimes. A total of 284,121 high-quality S-to-P receiver functions (SRFs) are obtained from 3,809 broadband seismic stations in the TA and other permanent and temporary deployments in the contiguous United States. The SRFs are computed using frequency domain deconvolution, and are stacked in consecutive circles with a radius of 2°. They are converted to depth series after move-out corrections using the IASP91 Earth model. Similar to previous SRF studies, a robust negative arrival, representing a sharp discontinuity of velocity reduction with depth, is visible in virtually all the stacked traces in the depth range of 30-110 km. Beneath the western US, the depth of this discontinuity is 69±17 km, and beneath the eastern US, it ranges from 75 to 90 km, both of which are comparable to the depth of the tomographically-determined lithosphere-asthenosphere boundary (LAB). In contrast, the depth of the discontinuity beneath the central US is 83±10 km which is significantly smaller than the 250 km LAB depth determined by seismic surface wave tomography. Based on previous seismic tomography, shear-wave splitting and mantle xenolith studies, we interpret this discontinuity as the top of a frozen-in layer of volatile-rich melt beneath the central US. The observations and the discrepancy between the SRF and seismic tomography results for the central US as well as the amplitude of the corresponding arrival on the SRFs may be explained by spatial variations of the thickness of the transitional layer between the "pure" lithosphere and the "pure" asthenosphere. Under this hypothesis, the consistency between the results from the

Estimating the unknown components of nutrient mass balances for forestry plantations in mine rehabilitation, upper Hunter Valley, New South Wales, Australia.

Science.gov (United States)

Mercuri, A M; Duggin, J A; Daniel, H; Lockwood, P V; Grant, C D

2006-04-01

Commercial forestry plantations as a postmining land use in the Upper Hunter Valley of New South Wales, Australia are restricted by both the poor nutrient availability of mining substrates and low regional rainfall. An experiment was conducted to investigate whether municipal waste products and saline groundwater from coal mining operations could improve early tree growth without impacting on the environment through salt accumulation and/or nutrient enrichment and changes in groundwater quality. Potential impacts were investigated by quantifying the nutrient cycling dynamics within the plantation using an input-output mass balance approach for exchangeable calcium (Ca(2+)), exchangeable magnesium (Mg(2+)), exchangeable potassium (K(+)), exchangeable sodium (Na(+)), nitrogen (N), and phosphorus (P). Measured inputs to and outputs from the available nutrient pool in the 0-30 cm of the overburden subsystem were used to estimate the net effect of unmeasured inputs and outputs (termed "residuals"). Residual values in the mass balance of the irrigated treatments demonstrated large leaching losses of exchangeable Ca, Mg, K, and Na. Between 96% and 103% of Na applied in saline mine-water irrigation was leached below the 0-30-cm soil profile zone. The fate of these salts beyond 30 cm is unknown, but results suggest that irrigation with saline mine water had minimal impact on the substrate to 30 cm over the first 2 years since plantation establishment. Accumulations of N and P were detected for the substrate amendments, suggesting that organic amendments (particularly compost) retained the applied nutrients with very little associated losses, particularly through leaching.

Upper Mantle Structure beneath Afar: inferences from surface waves.

Science.gov (United States)

Sicilia, D.; Montagner, J.; Debayle, E.; Lepine, J.; Leveque, J.; Cara, M.; Ataley, A.; Sholan, J.

2001-12-01

The Afar hotspot is related to one of the most important plume from a geodynamic point of view. It has been advocated to be the surface expression of the South-West African Superswell. Below the lithosphere, the Afar plume might feed other hotspots in central Africa (Hadiouche et al., 1989; Ebinger & Sleep, 1998). The processes of interaction between crust, lithosphere and plume are not well understood. In order to gain insight into the scientific issue, we have performed a surface-wave tomography covering the Horn of Africa. A data set of 1404 paths for Rayleigh waves and 473 paths for Love waves was selected in the period range 45-200s. They were collected from the permanent IRIS and GEOSCOPE networks and from the PASSCAL experiment, in Tanzania and Saudi Arabia. Other data come from the broadband stations deployed in Ethiopia and Yemen in the framework of the French INSU program ``Horn of Africa''. The results presented here come from a path average phase velocities obtained with a method based on a least-squares minimization (Beucler et al., 2000). The local phase velocity distribution and the azimuthal anisotropy were simultaneously retrieved by using the tomographic technique of Montagner (1986). A correction of the data is applied according to the crustal structure of the 3SMAC model (Nataf & Ricard, 1996). We find low velocities down to 200 km depth beneath the Red Sea, the Gulf of Aden, Afars, the Ethiopian Plateau and southern Arabia. High velocities are present in the eastern Arabia and the Tanzania Craton. The anisotropy beneath Afar seems to be complex, but enables to map the flow pattern at the interface lithosphere-asthenosphere. The results presented here are complementary to those obtained by Debayle et al. (2001) at upper-mantle transition zone depths using waveform inversion of higher Rayle igh modes.

Wall-pressure fluctuations beneath a spatially evolving turbulent boundary layer

Science.gov (United States)

Mahesh, Krishnan; Kumar, Praveen

2016-11-01

Wall-pressure fluctuations beneath a turbulent boundary layer are important in applications dealing with structural deformation and acoustics. Simulations are performed for flat plate and axisymmetric, spatially evolving zero-pressure-gradient turbulent boundary layers at inflow Reynolds number of 1400 and 2200 based on momentum thickness. The simulations generate their own inflow using the recycle-rescale method. The results for mean velocity and second-order statistics show excellent agreement with the data available in literature. The spectral characteristics of wall-pressure fluctuations and their relation to flow structure will be discussed. This work is supported by ONR.

Constraining spatial variations in P-wave velocity in the upper mantle beneath SE Asia

NARCIS (Netherlands)

Li, C.; Hilst, R.D. van der; Toksoz, N.M.

2006-01-01

We have produced a P-wave model of the upper mantle beneath Southeast (SE) Asia from reprocessed short period International Seismological Centre (ISC) P and pP data, short period P data of the Annual Bulletin of Chinese Earthquakes (ABCE), and long period PP-P data.We used 3D sensitivity kernels

Determination of Mantle Discontinuity Depths beneath the South Pacific Superswell As Inferred Using Data From Broadband OBS Array

Science.gov (United States)

Suetsugu, D.; Shiobara, H.; Sugioka, H.; Kanazawa, T.; Fukao, Y.

2005-12-01

We determined depths of the mantle discontinuities (the 410-km and 660-km discontinuities) beneath the South Pacific Superswell using waveform data from broadband ocean bottom seismograph (BBOBS) array to image presumed mantle plumes and their temperature anomalies. Seismic structure beneath this region had not previously been well explored in spite of its significance for mantle dynamics. The region is characterized by a topographic high of more than 680 m (Adam and Bonneville, 2005), a concentration of hotspot chains (e.g., Society, Cook-Austral, Marquesas, and Pitcairn) whose volcanic rocks have isotopic characteristics suggesting deep mantle origin, and a broad low velocity anomaly in the lower mantle revealed by seismic tomography. These observations suggest the presence of a whole-mantle scale upwelling beneath the region, which is called a 'superplume' (McNutt, 1998). However, the seismic structure has been only poorly resolved so far and the maximum depth of anomalous material beneath the hotspots has not yet been determined, mainly due to the sparseness of seismic stations in the region. To improve the seismic coverage, we deployed an array of 10 BBOBS over the French Polynesia area from 2003 to 2005. The BBOBS has been developed by Earthquake Research Institute of University of Tokyo and are equipped with the broadband CMG-3T/EBB sensor. The observation was conducted as a Japan-France cooperative project (Suetsugu et al., 2005, submitted to EOS). We computed receiver functions from the BBOBS data to detect Ps waves from the mantle discontinuities. The Velocity Spectrum Stacking method (Gurrola et al., 1994) were employed to enhance the Ps waves for determination of the discontinuity depths, in which receiver functions were stacked in a depth-velocity space. The Ps-waves from the mantle discontinuities were successfully detected at the most of the BBOBS stations, from which the discontinuity depths were determined with the Iasp91 velocity model. The 410-km

Stratigraphy of the late Cenozoic sediments beneath the 216-A Crib Facilities

International Nuclear Information System (INIS)

Fecht, K.R.; Last, G.V.; Marratt, M.C.

1979-02-01

The stratigraphy of the late Cenozoic sediments beneath the 216-A Crib Facilities is presented as lithofacies cross sections and is based on textural variations of the sedimentary sequence lying above the basalt bedrock. The primary source of data in this study is geologic information obtained from well drilling operations and geophysical logging. Stratigraphic interpretations are based primarily on textural analysis and visual examination of sediment samples and supplemented by drillers logs and geophysical logs

Soil microbial activities beneath Stipa tenacissima L. and in surrounding bare soil

Science.gov (United States)

Novosadová, I.; Ruiz Sinoga, J. D.; Záhora, J.; Fišerová, H.

2010-05-01

Open steppes dominated by Stipa tenacissima L. constitute one of the most representative ecosystems of the semi-arid zones of Eastern Mediterranean Basin (Iberian Peninsula, North of Africa). These steppes show a higher degree of variability in composition and structure. Ecosystem functioning is strongly related to the spatial pattern of grass tussocks. Soils beneath S. tenacissima grass show higher fertility and improved microclimatic conditions, favouring the formation of "resource islands" (Maestre et al., 2007). On the other hand in "resource islands" and in surrounding bare soil exists the belowground zone of influence. The competition for water and resources between plants and microorganisms is strong and mediated trough an enormous variety of exudates and resource depletion intended to regulate soil microbial communities in the rhizosphere, control herbivory, encourage beneficial symbioses, and change chemical and physical properties in soil (Pugnaire et Armas, 2008). Secondary compounds and allelopathy restrict other species growth and contribute to patchy plant distribution. Active root segregation affects not only neighbourś growth but also soil microbial activities. The objective of this study was to assess the effect of Stipa tenacissima on the key soil microbial activities under controlled incubation conditions (basal and potential respiration; net nitrogen mineralization). The experimental plots were located in the province Almería in Sierra de los Filabres Mountains near the village Gérgal (southeast Spain) in the small catchment which is situated between 1090 - 1165 m a.s.l. The area with extent of 82 000 m2 is affected by soil degradation. The climate is semiarid Mediterranean. The mean annual rainfall is of about 240 mm mostly concentrated in autumn and spring. The mean annual temperature is 13.9° C. The studied soil has a loam to sandy clay texture and is classified as Lithosol (FAO-ISRIC and ISSS, 1998). The vegetation of these areas is an

Mantle upwelling beneath Madagascar: evidence from receiver function analysis and shear wave splitting

Science.gov (United States)

Paul, Jonathan D.; Eakin, Caroline M.

2017-07-01

Crustal receiver functions have been calculated from 128 events for two three-component broadband seismomenters located on the south coast (FOMA) and in the central High Plateaux (ABPO) of Madagascar. For each station, crustal thickness and V p / V s ratio were estimated from H- κ plots. Self-consistent receiver functions from a smaller back-azimuthal range were then selected, stacked and inverted to determine shear wave velocity structure as a function of depth. These results were corroborated by guided forward modeling and by Monte Carlo error analysis. The crust is found to be thinner (39 ± 0.7 km) beneath the highland center of Madagascar compared to the coast (44 ± 1.6 km), which is the opposite of what would be expected for crustal isostasy, suggesting that present-day long wavelength topography is maintained, at least in part, dynamically. This inference of dynamic support is corroborated by shear wave splitting analyses at the same stations, which produce an overwhelming majority of null results (>96 %), as expected for vertical mantle flow or asthenospheric upwelling beneath the island. These findings suggest a sub-plate origin for dynamic support.

Transsulfuration pathway thiols and methylated arginines: the Hunter Community Study.

Directory of Open Access Journals (Sweden)

Arduino A Mangoni

Full Text Available Serum homocysteine, when studied singly, has been reported to be positively associated both with the endogenous nitric oxide synthase inhibitor asymmetric dimethylarginine [ADMA, via inhibition of dimethylarginine dimethylaminohydrolase (DDAH activity] and with symmetric dimethylarginine (SDMA. We investigated combined associations between transsulfuration pathway thiols, including homocysteine, and serum ADMA and SDMA concentrations at population level.Data on clinical and demographic characteristics, medication exposure, C-reactive protein, serum ADMA and SDMA (LC-MS/MS, and thiols (homocysteine, cysteine, taurine, glutamylcysteine, total glutathione, and cysteinylglycine; capillary electrophoresis were collected from a sample of the Hunter Community Study on human ageing [n = 498, median age (IQR = 64 (60-70 years].REGRESSION ANALYSIS SHOWED THAT: a age (P = 0.001, gender (P = 0.03, lower estimated glomerular filtration rate (eGFR, P = 0.08, body mass index (P = 0.008, treatment with beta-blockers (P = 0.03, homocysteine (P = 0.02, and glutamylcysteine (P = 0.003 were independently associated with higher ADMA concentrations; and b age (P = 0.001, absence of diabetes (P = 0.001, lower body mass index (P = 0.01, lower eGFR (P<0.001, cysteine (P = 0.007, and glutamylcysteine (P < 0.001 were independently associated with higher SDMA concentrations. No significant associations were observed between methylated arginines and either glutathione or taurine concentrations.After adjusting for clinical, demographic, biochemical, and pharmacological confounders the combined assessment of transsulfuration pathway thiols shows that glutamylcysteine has the strongest and positive independent associations with ADMA and SDMA. Whether this reflects a direct effect of glutamylcysteine on DDAH activity (for ADMA and/or cationic amino acid transport requires further investigations.

Early Neolithic water wells reveal the world's oldest wood architecture.

Science.gov (United States)

Tegel, Willy; Elburg, Rengert; Hakelberg, Dietrich; Stäuble, Harald; Büntgen, Ulf

2012-01-01

The European Neolithization ~6000-4000 BC represents a pivotal change in human history when farming spread and the mobile style of life of the hunter-foragers was superseded by the agrarian culture. Permanent settlement structures and agricultural production systems required fundamental innovations in technology, subsistence, and resource utilization. Motivation, course, and timing of this transformation, however, remain debatable. Here we present annually resolved and absolutely dated dendroarchaeological information from four wooden water wells of the early Neolithic period that were excavated in Eastern Germany. A total of 151 oak timbers preserved in a waterlogged environment were dated between 5469 and 5098 BC and reveal unexpectedly refined carpentry skills. The recently discovered water wells enable for the first time a detailed insight into the earliest wood architecture and display the technological capabilities of humans ~7000 years ago. The timbered well constructions made of old oak trees feature an unopened tree-ring archive from which annually resolved and absolutely dated environmental data can be culled. Our results question the principle of continuous evolutionary development in prehistoric technology, and contradict the common belief that metal was necessary for complex timber constructions. Early Neolithic craftsmanship now suggests that the first farmers were also the first carpenters.

Early Neolithic water wells reveal the world's oldest wood architecture.

Directory of Open Access Journals (Sweden)

Willy Tegel

Full Text Available The European Neolithization ~6000-4000 BC represents a pivotal change in human history when farming spread and the mobile style of life of the hunter-foragers was superseded by the agrarian culture. Permanent settlement structures and agricultural production systems required fundamental innovations in technology, subsistence, and resource utilization. Motivation, course, and timing of this transformation, however, remain debatable. Here we present annually resolved and absolutely dated dendroarchaeological information from four wooden water wells of the early Neolithic period that were excavated in Eastern Germany. A total of 151 oak timbers preserved in a waterlogged environment were dated between 5469 and 5098 BC and reveal unexpectedly refined carpentry skills. The recently discovered water wells enable for the first time a detailed insight into the earliest wood architecture and display the technological capabilities of humans ~7000 years ago. The timbered well constructions made of old oak trees feature an unopened tree-ring archive from which annually resolved and absolutely dated environmental data can be culled. Our results question the principle of continuous evolutionary development in prehistoric technology, and contradict the common belief that metal was necessary for complex timber constructions. Early Neolithic craftsmanship now suggests that the first farmers were also the first carpenters.

Probability of a surface rupture offset beneath a nuclear test reactor

International Nuclear Information System (INIS)

Reed, J.W.; Meehan, R.L.; Crellin, G.L.

1981-01-01

A probabilistic analysis was conducted to determine the likelihood of a surface rupture offset of any size beneath the 50 megawatt General Electric Test Reactor (GETR), which is located at the Vallecitos Nuclear Center near Pleasanton, California. Geologic faults have been observed at the GETR site. These faults may be due to surface folds, landslides, or deep tectonic movement. They are referred to in the paper as 'existing faults;' however, use of this term does not imply that they are tectonic in origin. The objective of the analysis was to evaluate whether a conservative estimate of the probability of occurrence of a future fault movement is sufficiently low so that movement beneath the reactor building need not be considered as a design basis event. The reactor building is located between two existing faults which are approximately 1320 feet apart. If a fault movement occurs in the future, it is conservatively assumed to occur either on the existing faults or between the faults, or on a fault(s) and between the two faults at the same time. The probabilistic model included the possibility of movements occurring due to unknown, undiscovered faults in the region. For this part, movements were assumed to occur according to a Poisson process. For the possibility of new faults occurring due to the two existing faults, a hazard function was used which increases with time since the last offset. (orig./RW)

Jaguar conservation in southern Belize: Conflicts, perceptions, and prospects among mayan hunters

Directory of Open Access Journals (Sweden)

Michael K Steinberg

2016-01-01

Full Text Available Belize has emerged as an international leader in jaguar conservation through the creation of numerous protected areas that contain prime cat habitat and by strengthening conservation laws. For example, in 1984, Belize created the Cockscomb Basin Jaguar Preserve, the first special jaguar protection area in the Americas. In 1995, the government expanded Cockscomb by creating the adjacent Chiquibul National Park. In 2010, the government continued this commitment to jaguar conservation by creating the Labouring Creek Jaguar Corridor Wildlife Sanctuary in central Belize. As a result of these protected areas, Belize has been rightfully lauded as a leader in nature-based tourism and protected areas creation in Central America. However, outside national parks and communities that directly benefit from ecotourism, it is less clear how supportive rural residents are of cat conservation. It is also not clear if jaguars persist outside protected areas in locations such as southern Belize, where the environment has been significantly altered by human activities. Through interviews with Mayan hunters, this paper investigates the attitudes towards jaguars, human-jaguar conflicts, and potential community-based jaguar conservation in two Mayan villages in the Toledo District in southern Belize. Also, using indirect methods, the paper documents the presence/absence and other temporal/spatial aspects of jaguars in a heavily altered landscape in southern Belize.

Hot upwelling conduit beneath the Atlas Mountains, Morocco

Science.gov (United States)

Sun, Daoyuan; Miller, Meghan S.; Holt, Adam F.; Becker, Thorsten W.

2014-11-01

The Atlas Mountains of Morocco display high topography, no deep crustal root, and regions of localized Cenozoic alkaline volcanism. Previous seismic imaging and geophysical studies have implied a hot mantle upwelling as the source of the volcanism and high elevation. However, the existence, shape, and physical properties of an associated mantle anomaly are debated. Here we use seismic waveform analysis from a broadband deployment and geodynamic modeling to define the physical properties and morphology of the anomaly. The imaged low-velocity structure extends to ~200 km beneath the Atlas and appears ~350 K hotter than the ambient mantle with possible partial melting. It includes a lateral conduit, which suggests that the Quaternary volcanism arises from the upper mantle. Moreover, the shape and temperature of the imaged anomaly indicate that the unusually high topography of the Atlas Mountains is due to active mantle support.

Heterogeneous Structure and Seismicity beneath the Tokyo Metropolitan Area

Science.gov (United States)

Nakagawa, S.; Kato, A.; Sakai, S.; Nanjo, K.; Panayotopoulos, Y.; Kurashimo, E.; Obara, K.; Kasahara, K.; Aketagawa, T.; Kimura, H.; Hirata, N.

2010-12-01

Beneath the Tokyo metropolitan area, the Philippine Sea Plate (PSP) subducts and causes damaged mega-thrust earthquakes. Sato et al. (2005) revealed the geometry of upper surface of PSP, and Hagiwara et al. (2006) estimated the velocity structure beneath Boso peninsula. However, these results are not sufficient for the assessment of the entire picture of the seismic hazards beneath the Tokyo metropolitan area including those due to an intra-slab M7+ earthquake. So, we launched the Special Project for Earthquake Disaster Mitigation in the Tokyo Metropolitan area (Hirata et al., 2009). Proving the more detailed geometry and physical properties (e.g. velocities, densities, attenuation) and stress field within PSP is very important to attain this issue. The core item of this project is a dense seismic array called Metropolitan Seismic Observation network (MeSO-net) for making observations in the metropolitan area (Sakai and Hirata, 2009; Kasahara et al., 2009). We deployed the 249 seismic stations with a spacing of 5 km. Some parts of stations construct 5 linear arrays at interval of 2 km such as Tsukuba-Fujisawa (TF) array, etc. The TF array runs from northeast to southwest through the center of Tokyo. In this study, we applied the tomography method to image the heterogeneous structure under the Tokyo metropolitan area. We selected events from the Japan Meteorological Agency (JMA) unified earthquake list. All data of MeSO-net were edited into event data by the selected JMA unified earthquake list. We picked the P and S wave arrival times. The total number of stations and events are 421 and 1,256, respectively. Then, we applied the double-difference tomography method (Zhang and Thurber, 2003) to this dataset and estimated the fine-scale velocity structure. The grid nodes locate 10 km interval in parallel with the array, 20 km interval in perpendicular to the array; and on depth direction, 5 km interval to a depth of less than 50 km and 10 km interval at a depth of more

Three-Dimensional P-wave Velocity Structure Beneath Long Valley Caldera, California, Using Local-Regional Double-Difference Tomography

Science.gov (United States)

Menendez, H. M.; Thurber, C. H.

2011-12-01

Eastern California's Long Valley Caldera (LVC) and the Mono-Inyo Crater volcanic systems have been active for the past ~3.6 million years. Long Valley is known to produce very large silicic eruptions, the last of which resulted in the formation of a 17 km by 32 km wide, east-west trending caldera. Relatively recent unrest began between 1978-1980 with five ML ≥ 5.7 non-double-couple (NDC) earthquakes and associated aftershock swarms. Similar shallow seismic swarms have continued south of the resurgent dome and beneath Mammoth Mountain, surrounding sites of increased CO2 gas emissions. Nearly two decades of increased volcanic activity led to the 1997 installation of a temporary three-component array of 69 seismometers. This network, deployed by the Durham University, the USGS, and Duke University, recorded over 4,000 high-frequency events from May to September. A local tomographic inversion of 283 events surrounding Mammoth Mountain yielded a velocity structure with low Vp and Vp/Vs anomalies at 2-3 km bsl beneath the resurgent dome and Casa Diablo hot springs. These anomalies were interpreted to be CO2 reservoirs (Foulger et al., 2003). Several teleseismic and regional tomography studies have also imaged low Vp anomalies beneath the caldera at ~5-15 km depth, interpreted to be the underlying magma reservoir (Dawson et al., 1990; Weiland et al., 1995; Thurber et al., 2009). This study aims to improve the resolution of the LVC regional velocity model by performing tomographic inversions using the local events from 1997 in conjunction with regional events recorded by the Northern California Seismic Network (NCSN) between 1980 and 2010 and available refraction data. Initial tomographic inversions reveal a low velocity zone at ~2 to 6 km depth beneath the caldera. This structure may simply represent the caldera fill. Further iterations and the incorporation of teleseismic data may better resolve the overall shape and size of the underlying magma reservoir.

Probing Earth’s conductivity structure beneath oceans by scalar geomagnetic data: autonomous surface vehicle solution

DEFF Research Database (Denmark)

Kuvshinov, Alexey; Matzka, Jürgen; Poedjono, Benny

2016-01-01

to the conductivity structure beneath the ocean. We conclude that the sensitivity, depending on the bathymetry gradient, is typically largest near the coast offshore. We show that such sea-surface marine induction surveys can be performed with the Wave Glider, an easy-to-deploy, autonomous, energy-harvesting floating...

The upper mantle beneath the Gulf of California from surface wave dispersion. Geologica Ultraiectina (299)

NARCIS (Netherlands)

Zhang, X.

2009-01-01

This thesis is a study on upper mantle shear velocity structure beneath the Gulf of California. Surface wave interstation dispersion data were measured in the Gulf of California area and vicinity to obtain a 3-D shear velocity structure of the upper mantle. This work has particular significance for

Seismic Structure of the Shallow Mantle Beneath the Endeavor Segment of the Juan de Fuca Ridge

Science.gov (United States)

VanderBeek, B. P.; Toomey, D. R.; Hooft, E. E.; Wilcock, W. S.; Weekly, R. T.; Soule, D. C.

2013-12-01

We present tomographic images of the seismic structure of the shallow mantle beneath the intermediate-spreading Endeavor segment of the Juan de Fuca ridge. Our results provide insight into the relationship between magma supply from the mantle and overlying ridge crest processes. We use seismic energy refracted below the Moho (Pn), as recorded by the Endeavor tomography (ETOMO) experiment, to image the anisotropic and isotropic P wave velocity structure. The ETOMO experiment was an active source seismic study conducted in August 2009 as part of the RIDGE2000 science program. The experimental area extends 100 km along- and 60 km across-axis and encompasses active hydrothermal vent fields near the segment center, the eastern end of the Heck seamount chain, and two overlapping spreading centers (OSCs) at either end of the segment. Previous tomographic analyses of seismic arrivals refracted through the crust (Pg), and reflected off the Moho (PmP), constrain a three-dimensional starting model of crustal velocity and thickness. These Pg and PmP arrivals are incorporated in our inversion of Pn travel-time data to further constrain the isotropic and anisotropic mantle velocity structure. Preliminary results reveal three distinct mantle low-velocity zones, inferred as regions of mantle melt delivery to the base of the crust, that are located: (i) off-axis near the segment center, (ii) beneath the Endeavor-West Valley OSC, and (iii) beneath the Cobb OSC near Split Seamount. The mantle anomalies are located at intervals of ~30 to 40 km along-axis and the low velocity anomalies beneath the OSCs are comparable in magnitude to the one located near the segment center. The direction of shallow mantle flow is inferred from azimuthal variations in Pn travel-time residuals relative to a homogeneous isotropic mantle. Continuing analysis will focus on constraining spatial variations in the orientation of azimuthal anisotropy. On the basis of our results, we will discuss the transport of

Early evidence of San material culture represented by organic artifacts from Border Cave, South Africa.

Science.gov (United States)

d'Errico, Francesco; Backwell, Lucinda; Villa, Paola; Degano, Ilaria; Lucejko, Jeannette J; Bamford, Marion K; Higham, Thomas F G; Colombini, Maria Perla; Beaumont, Peter B

2012-08-14

Recent archaeological discoveries have revealed that pigment use, beads, engravings, and sophisticated stone and bone tools were already present in southern Africa 75,000 y ago. Many of these artifacts disappeared by 60,000 y ago, suggesting that modern behavior appeared in the past and was subsequently lost before becoming firmly established. Most archaeologists think that San hunter-gatherer cultural adaptation emerged 20,000 y ago. However, reanalysis of organic artifacts from Border Cave, South Africa, shows that the Early Later Stone Age inhabitants of this cave used notched bones for notational purposes, wooden digging sticks, bone awls, and bone points similar to those used by San as arrowheads. A point is decorated with a spiral groove filled with red ochre, which closely parallels similar marks that San make to identify their arrowheads when hunting. A mixture of beeswax, Euphorbia resin, and possibly egg, wrapped in vegetal fibers, dated to ∼40,000 BP, may have been used for hafting. Ornaments include marine shell beads and ostrich eggshell beads, directly dated to ∼42,000 BP. A digging stick, dated to ∼39,000 BP, is made of Flueggea virosa. A wooden poison applicator, dated to ∼24,000 BP, retains residues with ricinoleic acid, derived from poisonous castor beans. Reappraisal of radiocarbon age estimates through bayesian modeling, and the identification of key elements of San material culture at Border Cave, places the emergence of modern hunter-gatherer adaptation, as we know it, to ∼44,000 y ago.

Imaging paleoslabs in the D″ layer beneath Central America and the Caribbean using seismic waveform inversion.

Science.gov (United States)

Borgeaud, Anselme F E; Kawai, Kenji; Konishi, Kensuke; Geller, Robert J

2017-11-01

D″ (Dee double prime), the lowermost layer of the Earth's mantle, is the thermal boundary layer (TBL) of mantle convection immediately above the Earth's liquid outer core. As the origin of upwelling of hot material and the destination of paleoslabs (downwelling cold slab remnants), D″ plays a major role in the Earth's evolution. D″ beneath Central America and the Caribbean is of particular geodynamical interest, because the paleo- and present Pacific plates have been subducting beneath the western margin of Pangaea since ~250 million years ago, which implies that paleoslabs could have reached the lowermost mantle. We conduct waveform inversion using a data set of ~7700 transverse component records to infer the detailed three-dimensional S-velocity structure in the lowermost 400 km of the mantle in the study region so that we can investigate how cold paleoslabs interact with the hot TBL above the core-mantle boundary (CMB). We can obtain high-resolution images because the lowermost mantle here is densely sampled by seismic waves due to the full deployment of the USArray broadband seismic stations during 2004-2015. We find two distinct strong high-velocity anomalies, which we interpret as paleoslabs, just above the CMB beneath Central America and Venezuela, respectively, surrounded by low-velocity regions. Strong low-velocity anomalies concentrated in the lowermost 100 km of the mantle suggest the existence of chemically distinct denser material connected to low-velocity anomalies in the lower mantle inferred by previous studies, suggesting that plate tectonics on the Earth's surface might control the modality of convection in the lower mantle.

Origin and tectonic evolution of early Paleozoic arc terranes abutting the northern margin of North China Craton

Science.gov (United States)

Zhou, Hao; Pei, Fu-Ping; Zhang, Ying; Zhou, Zhong-Biao; Xu, Wen-Liang; Wang, Zhi-Wei; Cao, Hua-Hua; Yang, Chuan

2017-12-01

The origin and tectonic evolution of the early Paleozoic arc terranes abutting the northern margin of the North China Craton (NCC) are widely debated. This paper presents detrital zircon U-Pb and Hf isotopic data of early Paleozoic strata in the Zhangjiatun arc terrane of central Jilin Province, northeast (NE) China, and compares them with the Bainaimiao and Jiangyu arc terranes abutting the northern margin of the NCC. Detrital zircons from early Paleozoic strata in three arc terranes exhibit comparable age groupings of 539-430, 1250-577, and 2800-1600 Ma. The Paleoproterozoic to Neoarchean ages and Hf isotopic composition of the detrital zircons imply the existence of the Precambrian fragments beneath the arc terranes. Given the evidences from geology, igneous rocks, and detrital zircons, we proposed that the early Paleozoic arc terranes abutting the northern margin of the NCC are a united arc terrane including the exotic Precambrian fragments, and these fragments shared a common evolutionary history from Neoproterozoic to early-middle Paleozoic.

Slab melting beneath the Cascades Arc driven by dehydration of altered oceanic peridotite

Science.gov (United States)

Walowski, Kristina J; Wallace, Paul J.; Hauri, E.H.; Wada, I.; Clynne, Michael A.

2015-01-01

Water is returned to Earth’s interior at subduction zones. However, the processes and pathways by which water leaves the subducting plate and causes melting beneath volcanic arcs are complex; the source of the water—subducting sediment, altered oceanic crust, or hydrated mantle in the downgoing plate—is debated; and the role of slab temperature is unclear. Here we analyse the hydrogen-isotope and trace-element signature of melt inclusions in ash samples from the Cascade Arc, where young, hot lithosphere subducts. Comparing these data with published analyses, we find that fluids in the Cascade magmas are sourced from deeper parts of the subducting slab—hydrated mantle peridotite in the slab interior—compared with fluids in magmas from the Marianas Arc, where older, colder lithosphere subducts. We use geodynamic modelling to show that, in the hotter subduction zone, the upper crust of the subducting slab rapidly dehydrates at shallow depths. With continued subduction, fluids released from the deeper plate interior migrate into the dehydrated parts, causing those to melt. These melts in turn migrate into the overlying mantle wedge, where they trigger further melting. Our results provide a physical model to explain melting of the subducted plate and mass transfer from the slab to the mantle beneath arcs where relatively young oceanic lithosphere is subducted.

The preliminary results: Internal seismic velocity structure imaging beneath Mount Lokon

Energy Technology Data Exchange (ETDEWEB)

Firmansyah, Rizky, E-mail: rizkyfirmansyah@hotmail.com [Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Bandung, 40132 (Indonesia); Nugraha, Andri Dian, E-mail: nugraha@gf.itb.ac.id [Global Geophysical Group, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Bandung, 40132 (Indonesia); Kristianto, E-mail: kris@vsi.esdm.go.id [Center for Volcanology and Geological Hazard Mitigation (CVGHM), Geological Agency, Bandung, 40122 (Indonesia)

2015-04-24

Historical records that before the 17{sup th} century, Mount Lokon had been dormant for approximately 400 years. In the years between 1350 and 1400, eruption ever recorded in Empung, came from Mount Lokon’s central crater. Subsequently, in 1750 to 1800, Mount Lokon continued to erupt again and caused soil damage and fall victim. After 1949, Mount Lokon dramatically increased in its frequency: the eruption interval varies between 1 – 5 years, with an average interval of 3 years and a rest interval ranged from 8 – 64 years. Then, on June 26{sup th}, 2011, standby alert set by the Center for Volcanology and Geological Hazard Mitigation. Peak activity happened on July 4{sup th}, 2011 that Mount Lokon erupted continuously until August 28{sup th}, 2011. In this study, we carefully analyzed micro-earthquakes waveform and determined hypocenter location of those events. We then conducted travel time seismic tomographic inversion using SIMULPS12 method to detemine Vp, Vs and Vp/Vs ratio structures beneath Lokon volcano in order to enhance our subsurface geological structure. During the tomographic inversion, we started from 1-D seismic velocities model obtained from VELEST33 method. Our preliminary results show low Vp, low Vs, and high Vp/Vs are observed beneath Mount Lokon-Empung which are may be associated with weak zone or hot material zones. However, in this study we used few station for recording of micro-earthquake events. So, we suggest in the future tomography study, the adding of some seismometers in order to improve ray coverage in the region is profoundly justified.

The night of the hunter: children & adults in the secret

Directory of Open Access Journals (Sweden)

Terry caesar

2010-04-01

Full Text Available Night of the Hunter is  the 1956 Charles Laughton’s film considered  one of the best discussions about childhood. In this film, the story revolves around the fate of John and Pearl, two orphaned siblings whose father was hanged for stealing. The father had given the children the money, and they hid the money inside the girl’s doll. When the Preacher Powell enters their lives , both John and Pearl are in danger. The siblings have to keep a secret which is both where they put the money, and the fact that, for children, money is simply paper.

Receiver Function Imaging of Mantle Transition Zone Discontinuities Beneath Alaska

Science.gov (United States)

Dahm, Haider Hassan Faraj

Subduction of tectonic plates is one of the most important tectonic processes, yet many aspects of subduction zone geodynamics remain unsolved and poorly understood, such as the depth extent of the subducted slab and its geometry. The Alaska subduction zone, which is associated with the subduction of the Pacific Plate beneath the North America plate, has a complex tectonic setting and carries a series of subduction episodes, and represents an excellent target to study such plate tectonic processes. Previous seismological studies in Alaska have proposed different depth estimations and geometry for the subducted slab. The Mantle transition zone discontinuities of the 410km and the 660 km provide independent constraints on the depth extent of the subducted slabs. We conducted a receiver function study to map the topography of the 410 km and the 660 km discontinuities beneath Alaska and its adjacent areas by taking advantage of the teleseismic data from the new USArray deployment in Alaska and northwestern Canada. Stacking over 75,000 high-quality radial receiver functions recorded in Alaska with more than 40 years of recording period, the topographies of the 410 km and 660 km are mapped. The depths of both d410 and d660 show systematic spatial variations, the mean depth of d410 and d660 are within 6 km and 6 km from the global average, respectively. The mean MTZ thickness of the entire study area is within -2 km from the global average of 250 km, suggesting normal MTZ conditions on average. Central and south-central Alaska are characterized by a larger than normal MTZ thickness, suggesting that the subducting Pacific slab is thermally interacted with the MTZ. This study shows that lateral upper mantle velocity variations contribute the bulk of the observed apparent undulations of the MTZ discontinuities.

Evidence for partial melt in the crust beneath Mt. Paektu (Changbaishan), Democratic People’s Republic of Korea and China

Science.gov (United States)

Kyong-Song, Ri; Hammond, James O. S.; Chol-Nam, Ko; Hyok, Kim; Yong-Gun, Yun; Gil-Jong, Pak; Chong-Song, Ri; Oppenheimer, Clive; Liu, Kosima W.; Iacovino, Kayla D.; Kum-Ran, Ryu

2016-01-01

Mt. Paektu (also known as Changbaishan) is an enigmatic volcano on the border between the Democratic People’s Republic of Korea (DPRK) and China. Despite being responsible for one of the largest eruptions in history, comparatively little is known about its magmatic evolution, geochronology, or underlying structure. We present receiver function results from an unprecedented seismic deployment in the DPRK. These are the first estimates of the crustal structure on the DPRK side of the volcano and, indeed, for anywhere beneath the DPRK. The crust 60 km from the volcano has a thickness of 35 km and a bulk VP/VS of 1.76, similar to that of the Sino-Korean craton. The VP/VS ratio increases ~20 km from the volcano, rising to >1.87 directly beneath the volcano. This shows that a large region of the crust has been modified by magmatism associated with the volcanism. Such high values of VP/VS suggest that partial melt is present in the crust beneath Mt. Paektu. This region of melt represents a potential source for magmas erupted in the last few thousand years and may be associated with an episode of volcanic unrest observed between 2002 and 2005.

Thermo-Compositional Evolution of a Brine Reservoir Beneath Ceres' Occator Crater and Implications for Cryovolcanism at the Surface

Science.gov (United States)

Quick, L. C.

2017-12-01

The Dawn spacecraft has imaged several putative cryovolcanic features on Ceres (Buczkowski et al., 2016; Ruesch et al., 2016), and several lines of evidence point to past cryovolcanic activity at Occator crater (De Sanctis et al., 2016; Krohn et al., 2016; Buczkowski et al., 2017; Nathues et al., 2017; Ruesch et al., 2017; Zolotov, 2017). Hence it is possible that cryovolcanism played a key role in delivering carbonate and/or chloride brines to Ceres' surface in the past. As any cryolavas delivered to the surface would have issued from a briny subsurface reservoir, or, cryomagma chamber, it is necessary to consider the thermal and compositional evolution of such a reservoir. The detection of a 200 km x 200 km negative Bouguer anomaly beneath Occator suggests the presence of a low-density region beneath the crater (Ermakov et al., 2017). If this region is a residual cryomagma chamber, excess pressures caused by its gradual freezing, or stresses produced by the Occator-forming impact, could have once facilitated the delivery of cryolavas to the Cerean surface. I have investigated the progressive solidification of a cryomagma chamber beneath Occator and implications for the changing compositions of cryolavas on Ceres. I will present the results of this study as well as discuss the dynamics and heat transfer associated with cryomagmatic ascent to the surface. Preliminary results suggest that a 200 km wide cryomagma chamber situated beneath Ceres' crust would take approximately 1 Gyr to completely crystallize. However, such a reservoir would be depleted in chloride and carbonate salts after only 54 Myr of cooling. If the reservoir contained NH3-bearing fluids, eruptions could proceed for another 100 Myr before increased reservoir crystallization rendered cryomagmatic fluids completely immobile. In addition, it is likely that cryomagmas delivered to Ceres' surface had viscosities < 108 Pa s, and were delivered in fractures with propagation speeds ≥ 10-5 m/s. I will

Depth-Dependent Earthquake Properties Beneath Long-Beach, CA: Implications for the Rheology at the Brittle-Ductile Transition Zone

Science.gov (United States)

Inbal, A.; Clayton, R. W.; Ampuero, J. P.

2015-12-01

Except for a few localities, seismicity along faults in southern California is generally confined to depths shallower than 15 km. Among faults hosting deep seismicity, the Newport-Inglewood Fault (NIF), which traverses the Los-Angeles basin, has an exceptionally mild surface expression and low deformation rates. Moreover, the NIF structure is not as well resolved as other, less well instrumented faults because of poor signal-to-noise ratio. Here we use data from three temporary dense seismic arrays, which were deployed for exploration purposes and contain up to several thousands of vertical geophones, to investigate the properties of deep seismicity beneath Long-Beach (LB), Compton and Santa-Fe Springs (SFS). The latter is located 15 km northeast of the NIF, presumably above a major detachment fault underthrusting the basin.Event detection is carried out using a new approach for microseismic multi-channel picking, in which downward-continued data are back-projected onto the volume beneath the arrays, and locations are derived from statistical analysis of back-projection images. Our technique reveals numerous, previously undetected events along the NIF, and confirms the presence of an active shallow structure gently dipping to the north beneath SFS. Seismicity characteristics vary along the NIF strike and dip. While LB seismicity is uncorrelated with the mapped trace of the NIF, Compton seismicity illuminates a sub-vertical fault that extends down to about 20 km. This result, along with the reported high flux of mantle Helium along the NIF (Boles et al., 2015), suggests that the NIF is deeply rooted and acts as a major conduit for mantle fluids. We find that the LB size distribution obeys the typical power-law at shallow depths, but falls off exponentially for events occurring below 20 km. Because deep seismicity occurs uniformly beneath LB, this transition is attributed to a reduction in seismic asperity density with increasing depth, consistent with a transition

Electrical resistivity dynamics beneath a fractured sedimentary bedrock riverbed in response to temperature and groundwater–surface water exchange

Directory of Open Access Journals (Sweden)

C. M. Steelman

2017-06-01

Full Text Available Bedrock rivers occur where surface water flows along an exposed rock surface. Fractured sedimentary bedrock can exhibit variable groundwater residence times, anisotropic flow paths, and heterogeneity, along with diffusive exchange between fractures and rock matrix. These properties of the rock will affect thermal transients in the riverbed and groundwater–surface water exchange. In this study, surface electrical methods were used as a non-invasive technique to assess the scale and temporal variability of riverbed temperature and groundwater–surface water interaction beneath a sedimentary bedrock riverbed. Conditions were monitored at a semi-daily to semi-weekly interval over a full annual period that included a seasonal freeze–thaw cycle. Surface electromagnetic induction (EMI and electrical resistivity tomography (ERT methods captured conditions beneath the riverbed along a pool–riffle sequence of the Eramosa River in Canada. Geophysical datasets were accompanied by continuous measurements of aqueous specific conductance, temperature, and river stage. Time-lapse vertical temperature trolling within a lined borehole adjacent to the river revealed active groundwater flow zones along fracture networks within the upper 10 m of rock. EMI measurements collected during cooler high-flow and warmer low-flow periods identified a spatiotemporal riverbed response that was largely dependent upon riverbed morphology and seasonal groundwater temperature. Time-lapse ERT profiles across the pool and riffle sequence identified seasonal transients within the upper 2 and 3 m of rock, respectively, with spatial variations controlled by riverbed morphology (pool versus riffle and dominant surficial rock properties (competent versus weathered rock rubble surface. While the pool and riffle both exhibited a dynamic resistivity through seasonal cooling and warming cycles, conditions beneath the pool were more variable, largely due to the formation of river

Effect of resource spatial correlation and hunter-fisher-gatherer mobility on social cooperation in Tierra del Fuego.

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José Ignacio Santos

Full Text Available This article presents an agent-based model designed to explore the development of cooperation in hunter-fisher-gatherer societies that face a dilemma of sharing an unpredictable resource that is randomly distributed in space. The model is a stylised abstraction of the Yamana society, which inhabited the channels and islands of the southernmost part of Tierra del Fuego (Argentina-Chile. According to ethnographic sources, the Yamana developed cooperative behaviour supported by an indirect reciprocity mechanism: whenever someone found an extraordinary confluence of resources, such as a beached whale, they would use smoke signals to announce their find, bringing people together to share food and exchange different types of social capital. The model provides insight on how the spatial concentration of beachings and agents' movements in the space can influence cooperation. We conclude that the emergence of informal and dynamic communities that operate as a vigilance network preserves cooperation and makes defection very costly.

Re-evaluating the resource potential of lomas fog oasis environments for Preceramic hunter-gatherers under past ENSO modes on the south coast of Peru

Science.gov (United States)

Beresford-Jones, David; Pullen, Alexander G.; Whaley, Oliver Q.; Moat, Justin; Chauca, George; Cadwallader, Lauren; Arce, Susana; Orellana, Alfonso; Alarcón, Carmela; Gorriti, Manuel; Maita, Patricia K.; Sturt, Fraser; Dupeyron, Agathe; Huaman, Oliver; Lane, Kevin J.; French, Charles

2015-12-01

Lomas - ephemeral seasonal oases sustained by ocean fogs - were critical to ancient human ecology on the desert Pacific coast of Peru: one of humanity's few independent hearths of agriculture and "pristine" civilisation. The role of climate change since the Late Pleistocene in determining productivity and extent of past lomas ecosystems has been much debated. Here we reassess the resource potential of the poorly studied lomas of the south coast of Peru during the long Middle Pre-ceramic period (c. 8000-4500 BP): a period critical in the transition to agriculture, the onset of modern El Niño Southern Oscillation ('ENSO') conditions, and eustatic sea-level rise and stabilisation and beach progradation. Our method combines vegetation survey and herbarium collection with archaeological survey and excavation to make inferences about both Preceramic hunter-gatherer ecology and the changed palaeoenvironments in which it took place. Our analysis of newly discovered archaeological sites - and their resource context - show how lomas formations defined human ecology until the end of the Middle Preceramic Period, thereby corroborating recent reconstructions of ENSO history based on other data. Together, these suggest that a five millennia period of significantly colder seas on the south coast induced conditions of abundance and seasonal predictability in lomas and maritime ecosystems, that enabled Middle Preceramic hunter-gatherers to reduce mobility by settling in strategic locations at the confluence of multiple eco-zones at the river estuaries. Here the foundations of agriculture lay in a Broad Spectrum Revolution that unfolded, not through population pressure in deteriorating environments, but rather as an outcome of resource abundance.

Perceptions of on-site hunters: Environmental concerns, future land use, and cleanup options at the Savannah River Site

International Nuclear Information System (INIS)

Burger, J.; Sanchez, J.

1999-01-01

The Department of Energy owns land in 34 states, and most of these lands have been off limits to the public for over 50 years. Although some parts of each site are contaminated, most of many sites are not. With the ending of the Cold War, the department is considering alternative land uses. In this article, the perceptions of hunters and fishermen allowed on site for a limited time were examined, about environmental concerns, future land use, and cleanup options. Although loss of jobs was the foremost concern, preserving parts of the site had more support as a future land use than continuing the nuclear mission, and nearly three-quarters of the sample supported cleanup, regardless of cost. On-site employment was a significant indicator of lower concern about safety and environmental issues, less support for designating the site for research, and more concern for maintaining jobs

Robert Plant (1818–1858: A Victorian plant hunter in Natal, Zululand, Mauritius and the Seychelles

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Donal P. McCracken

2011-03-01

Full Text Available In the 1850s Robert William Plant collected plants and other natural specimens in what is now KwaZulu-Natal. This one-time Englishman compiled a dictionary for gardeners before emigrating to Natal in 1850. There he worked as the agent for Samuel Stevens, the London dealer in ‘curiosities of natural history’. Though Plant collected mainly plants, he also sent consignments of beetles, butterflies, bird skins and shells back to Britain. He published the first scientific paper on Zululand and was requested by the Royal Botanic Gardens at Kew to write the first Flora natalensis. It was while collecting for this never-to-be-completed treatise that Plant contracted malaria in Maputaland. He died in St Lucia in 1858 and in doing so became South Africa’s martyr to botany. What emerges from this study is a picture of the difficulties faced by plant hunters in mid-19th-century South Africa, the sort of plants they collected and the necessity for them sometimes to diversify into other natural history products to survive.

TEACHER OF EARLY EDUCATION IN THE ROLE OF A TRAPPER-CREATOR OF LIBERATING EDUCATION

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Jolanta Maciąg

2017-03-01

Full Text Available The modern civilization is characterised by a significant degree of development in thefields of science, technology and industry – which leads to numerous transformations in thefunctioning of traditional communities and societies, population migrations and creation ofnew groups and socio-professional layers. Due to the above-mentioned transformations, humaninterpersonal relations are frequently subject to the process of depersonalization, manifesting atendency to objectify people. Observing social changes that have been transpiring in Polandrecently as well as attempts to reform the educational system result in an increased importanceof questions concerning the role played by teachers and tasks they are to perform.According to Aleksander Nalaskowski, “a school is worth only as much as the teacherswho work in it”1. Answering the questions of ”Who currently works in Polish schools?” “Whoare our teachers?”- the author comes to the conclusion that we no longer encounter teacherteams at schools but only purely accidental gatherings of teachers. Such arbitrarily composedteacher assemblies do not form a unity, a characteristic group with numerous individual traits2.I consider it worthwhile to focus on the issue of professional awareness and professionalcompetences and qualifications of the teacher of children in the pre-school and early schoolstages (the so-called early education. School functioning is, after all, all the more effective ifthe teachers cooperate with one another, have a better understanding of children’s needs andare able to jointly improve their individual styles of work. In this article, I shall make anattempt to present a story of a teacher on a road, a trapper (to use a metaphor, a freeman/hunter in the process of permanent learning of the surrounding world. A reality which is tothe same extent expected and unpredictable as it fluctuates between the known and/versus thediscovered. The postmodern view of the world is

City Life in the Midst of the Forest: a Punan Hunter-Gatherer's Vision of Conservation and Development

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Patrice Levang

2007-06-01

Full Text Available The Punan Tubu, a group of hunter-gatherers in East-Kalimantan, Indonesia, are used to illustrate the very real trade-offs that are made between conservation and development. This group has undergone various forms of resettlement in the 20th century, to the point that some are now settled close to the city of Malinau whereas others remain in remote locations in the upper Tubu catchment. This study is based on several years of ethnographic and household analysis. The Punan clearly favor both conservation and development. In the city, the Punan benefit from all positive effects of development. Child and infant mortality rates are very low, and illiteracy has been eradicated among the younger generation. However, the Punan complain that nothing in town is free. The older generation, in particular, resents the loss of Punan culture. Because of frustration and unemployment, young people often succumb to alcoholism and drug addiction. The Punan do not want to choose between conservation and development, between forest life and city life. They want to benefit from the advantages of both locations, to enjoy both free forest products and the positive aspects of modern life, to go wild boar hunting in the morning and watch television in the evening. In short, they want to enjoy city life in the midst of the forest. The same kind of contradiction has led to identity problems. They want to uphold the traditional life of the hunter-gatherer, but at the same time they reject marginalization and seek integration into the larger society. In short, they want integration without loss of identity. The settlement of Sule-Pipa illustrates how some groups have dealt with the contradiction more successfully. Thanks to good organization and charitable donations, they have secured educational facilities and basic health care, and marketing costs are reduced by collectively organized road and river transportation. The economy of the village is thriving, mainly because of

Seismic Constraints on the Lithosphere-Asthenosphere Boundary Beneath the Izu-Bonin Area: Implications for the Oceanic Lithospheric Thinning

Science.gov (United States)

Cui, Qinghui; Wei, Rongqiang; Zhou, Yuanze; Gao, Yajian; Li, Wenlan

2018-01-01

The lithosphere-asthenosphere boundary (LAB) is the seismic discontinuity with negative velocity contrasts in the upper mantle. Seismic detections on the LAB are of great significance in understanding the plate tectonics, mantle convection and lithospheric evolution. In this paper, we study the LAB in the Izu-Bonin subduction zone using four deep earthquakes recorded by the permanent and temporary seismic networks of the USArray. The LAB is clearly revealed with sP precursors (sdP) through the linear slant stacking. As illustrated by reflected points of the identified sdP phases, the depth of LAB beneath the Izu-Bonin Arc (IBA) is about 65 km with a range of 60-68 km. The identified sdP phases with opposite polarities relative to sP phases have the average relative amplitude of 0.21, which means a 3.7% velocity drop and implies partial melting in the asthenosphere. On the basis of the crustal age data, the lithosphere beneath the IBA is located at the 1100 °C isotherm calculated with the GDH1 model. Compared to tectonically stable areas, such as the West Philippine Basin (WPB) and Parece Vela Basin (PVB) in the Philippine Sea, the lithosphere beneath the Izu-Bonin area shows the obvious lithospheric thinning. According to the geodynamic and petrological studies, the oceanic lithospheric thinning phenomenon can be attributed to the strong erosion of the small-scale convection in the mantle wedge enriched in volatiles and melts.

Attractiveness of the landscape: Reconstruction of Early to Middle Holocene landscape and occupation history of Flevoland (central Netherlands)

Science.gov (United States)

Van den Biggelaar, Don; Kluiving, Sjoerd; Van Balen, Ronald; Kasse, Kees; Kolen, Jan

2013-04-01

The onset of the Holocene (11 500 BP) is marked by climate warming. Climate warming induced the growth of vegetation, which in combination with precipitation and a long period of non-deposition resulted in the formation of soils at the top of the Pleistocene deposits. As these soils have been present at the surface in Flevoland (central Netherlands) during most of the Mesolithic and Neolithic period, the top Pleistocene is an important archaeological level. Prior to the 1990s, prehistoric occupation in wetland areas, such as the Flevoland region, was seen as a challenging living environment due to its marginal nature. However, since the early 1990s a different approach was raised concerning the suitability of wetland occupation by Mesolithic and Neolithic people. Instead of adapting to the natural conditions, prehistoric people selected an area suitable to their way of life. The question remains why it took so long (Mesolithic-Neolithic transition period: 5300-4600 cal BC) for the inhabitants of the Lower Rhine Basin to adapt to the Neolithic lifestyle, in contrast to the adaptation in the loess zone and later in Britain. This difference in adaptation of the Neolithic lifestyle during this transition period cannot be solely explained by a difference in attitude or other cultural arguments. As postglacial sea-level rise caused large parts of Flevoland (central Netherlands) to inundate during the Late Mesolithic and Early Neolithic, the availability of natural resources also changed. It is hypothesized that the availability of a wide range of natural resources, and not exclusively the soil type, predominantly determined the suitability and attractiveness of a region for hunter/gatherers and therefore delayed the transition to a Neolithic lifestyle. To test this hypothesis we have compared two selected areas on the basis of the following parameters: elevation, slope gradient relative to sea-level rise, soil type, past vegetation and the number of archaeological

S-P wave travel time residuals and lateral inhomogeneity in the mantle beneath Tibet and the Himalaya

Science.gov (United States)

Molnar, P.; Chen, W.-P.

1984-01-01

S-P wave travel time residuals were measured in earthquakes in Tibet and the Himalaya in order to study lateral inhomogeneities in the earth's mantle. Average S-P residuals, measured with respect to Jeffrey-Bullen (J-B) tables for 11 earthquakes in the Himalaya are less than +1 second. Average J-B S-P from 10 of 11 earthquakes in Tibet, however, are greater than +1 second even when corrected for local crustal thickness. The largest values, ranging between 2.5 and 4.9 seconds are for five events in central and northern Tibet, and they imply that the average velocities in the crust and upper mantle in this part of Tibet are 4 to 10 percent lower than those beneath the Himalaya. On the basis of the data, it is concluded that it is unlikely that a shield structure lies beneath north central Tibet unless the S-P residuals are due to structural variations occurring deeper than 250 km.

Unusually thickened crust beneath the Emeishan large igneous province detected by virtual deep seismic sounding

Science.gov (United States)

Liu, Zhen; Tian, Xiaobo; Chen, Yun; Xu, Tao; Bai, Zhiming; Liang, Xiaofeng; Iqbal, Javed; Xu, Yigang

2017-11-01

The Emeishan Large Igneous Province (ELIP) in southwest China represents the erosional remnant of a vast basalt field emplaced during the Permian Period. Spanning 0.25 million km2, the ELIP occupies a relatively small area relative to other Large Igneous Provinces (LIPs) such as the Siberian Traps and Ontong Java Plateau. The original volume of an ancient LIP can be constrained from estimates of its intrusive component. We used virtual deep seismic sounding (VDSS) to detect the boundary between the crust and the upper mantle (Moho) beneath the ELIP. A strong set of reflections from depths of 60-70 km indicate an unusually thick crust having a P-wave velocity of 7.0-7.4 km/s located beneath the inner zone of the ELIP. A high-velocity lower crustal body (HVLCB) of this thickness may have been formed by ponding magmas derived from the Emeishan mantle plume and associated fractionated materials. Combined images of crustal structure allow re-estimation of Emeishan magmatic volume. With a total estimated volume of 1.76-3.2 × 106 km3, the ELIP appears to have been a typical sized plume-generated LIP relative to other global examples.

Resource scarcity drives lethal aggression among prehistoric hunter-gatherers in central California.

Science.gov (United States)

Allen, Mark W; Bettinger, Robert Lawrence; Codding, Brian F; Jones, Terry L; Schwitalla, Al W

2016-10-25

The origin of human violence and warfare is controversial, and some scholars contend that intergroup conflict was rare until the emergence of sedentary foraging and complex sociopolitical organization, whereas others assert that violence was common and of considerable antiquity among small-scale societies. Here we consider two alternative explanations for the evolution of human violence: (i) individuals resort to violence when benefits outweigh potential costs, which is likely in resource poor environments, or (ii) participation in violence increases when there is coercion from leaders in complex societies leading to group level benefits. To test these hypotheses, we evaluate the relative importance of resource scarcity vs. sociopolitical complexity by evaluating spatial variation in three macro datasets from central California: (i) an extensive bioarchaeological record dating from 1,530 to 230 cal BP recording rates of blunt and sharp force skeletal trauma on thousands of burials, (ii) quantitative scores of sociopolitical complexity recorded ethnographically, and (iii) mean net primary productivity (NPP) from a remotely sensed global dataset. Results reveal that sharp force trauma, the most common form of violence in the record, is better predicted by resource scarcity than relative sociopolitical complexity. Blunt force cranial trauma shows no correlation with NPP or political complexity and may reflect a different form of close contact violence. This study provides no support for the position that violence originated with the development of more complex hunter-gatherer adaptations in the fairly recent past. Instead, findings show that individuals are prone to violence in times and places of resource scarcity.

The lithosphere-asthenosphere boundary beneath the Korean Peninsula from S receiver functions

Science.gov (United States)

Lee, S. H.; Rhie, J.

2017-12-01

The shallow lithosphere in the Eastern Asia at the east of the North-South Gravity Lineament is well published. The reactivation of the upper asthenosphere induced by the subducting plates is regarded as a dominant source of the lithosphere thinning. Additionally, assemblage of various tectonic blocks resulted in complex variation of the lithosphere thickness in the Eastern Asia. Because, the Korean Peninsula located at the margin of the Erasian Plate in close vicinity to the trench of subducting oceanic plate, significant reactivation of the upper asthenosphere is expected. For the study of the tectonic history surrounding the Korean Peninsula, we determined the lithosphere-asthenosphere boundary (LAB) beneath the Korean Peninsula using common conversion point stacking method with S receiver functions. The depth of the LAB beneath the Korean Peninsula ranges from 60 km to 100 km and confirmed to be shallower than that expected for Cambrian blocks as previous global studies. The depth of the LAB is getting shallower to the south, 95 km at the north and 60 km at the south. And rapid change of the LAB depth is observed between 36°N and 37°N. The depth change of the LAB getting shallower to the south implies that the source of the lithosphere thinning is a hot mantle upwelling induced by the northward subduction of the oceanic plates since Mesozoic. Unfortunately, existing tectonic models can hardly explain the different LAB depth in the north and in the south as well as the rapid change of the LAB depth.

Understanding seismic heterogeneities in the lower mantle beneath the Americas from seismic tomography and plate tectonic history

NARCIS (Netherlands)

Ren, Y.; Stutzmann, E.; Hilst, R.D. van der; Besse, J.

2007-01-01

We combine results from seismic tomography and plate motion history to investigate slabs of subducted lithosphere in the lower mantle beneath the Americas. Using broadband waveform cross correlation, we measured 37,000 differential P and S traveltimes, 2000 PcP-P and ScS-S times along a wide

Temperature increase beneath etched dentin discs during composite polymerization.

Science.gov (United States)

Karaarslan, Emine Sirin; Secilmis, Asli; Bulbul, Mehmet; Yildirim, Cihan; Usumez, Aslihan

2011-01-01

The purpose of this in vitro study was to measure the temperature increase during the polymerization of a composite resin beneath acid-etched or laser-etched dentin discs. The irradiation of dentin with an Er:YAG laser may have a positive effect on the thermal conductivity of dentin. This technique has not been studied extensively. Forty dentin discs (5 mm in diameter and 0.5 or 1 mm in height) were prepared from extracted permanent third molars. These dentin discs were etched with 20% orthophosphoric acid or an Er:YAG laser, and were then placed on an apparatus developed to measure temperature increases. The composite resin was polymerized with a high-intensity quartz tungsten halogen (HQTH) or light-emitting diode unit (LED). The temperature increase was measured under the dentin disc with a J-type thermocouple wire that was connected to a data logger. Five measurements were made for each dentin disc, curing unit, and etching system combination. Differences between the initial and the highest temperature readings were taken, and the five calculated temperature changes were averaged to determine the value of the temperature increase. Statistical analysis was performed with a three-way ANOVA and Tukey HSD tests at a 0.05 level of significance. Further SEM examinations were performed. The temperature increase values varied significantly, depending on etching systems (p < 0.05), dentin thicknesses (p < 0.05), and curing units (p < 0.05). Temperature increases measured beneath laser-etched discs were significantly higher than those for acid-etched dentin discs (p < 0.05). The HQTH unit induced significantly higher temperature increases than the LED unit (p < 0.05). The LED unit induced the lowest temperature change (5.2°C) in the 1-mm, acid-etched dentin group. The HQTH unit induced the highest temperature change (10.4°C) for the 0.5-mm, laser-etched dentin group. The risk of heat-induced pulpal damage should be taken into consideration

Hydrologic assessment of the shallow groundwater flow system beneath the Shinnecock Nation tribal lands, Suffolk County, New York

Science.gov (United States)

Noll, Michael L.; Rivera, Simonette L.; Busciolano, Ronald J.

2016-12-02

Defining the distribution and flow of shallow groundwater beneath the Shinnecock Nation tribal lands in Suffolk County, New York, is a crucial first step in identifying sources of potential contamination to the surficial aquifer and coastal ecosystems. The surficial or water table aquifer beneath the tribal lands is the primary source of potable water supply for at least 6 percent of the households on the tribal lands. Oyster fisheries and other marine ecosystems are critical to the livelihood of many residents living on the tribal lands, but are susceptible to contamination from groundwater entering the embayment from the surficial aquifer. Contamination of the surficial aquifer from flooding during intense coastal storms, nutrient loading from fertilizers, and septic effluent have been identified as potential sources of human and ecological health concerns on tribal lands.The U.S. Geological Survey (USGS) facilitated the installation of 17 water table wells on and adjacent to the tribal lands during March 2014. These wells were combined with other existing wells to create a 32-well water table monitoring network that was used to assess local hydrologic conditions. Survey-grade, global-navigation-satellite systems provided centimeter-level accuracy for positioning wellhead surveys. Water levels were measured by the USGS during May (spring) and November (fall) 2014 to evaluate seasonal effects on the water table. Water level measurements were made at high and low tide during May 2014 to identify potential effects on the water table caused by changes in tidal stage (tidal flux) in Shinnecock Bay. Water level contour maps indicate that the surficial aquifer is recharged by precipitation and upgradient groundwater flow that moves from the recharge zone located generally beneath Sunrise Highway, to the discharge zone beneath the tribal lands, and eventually discharges into the embayment, tidal creeks, and estuaries that bound the tribal lands to the east, south, and

The genomic history of southeastern Europe.

Science.gov (United States)

Mathieson, Iain; Alpaslan-Roodenberg, Songül; Posth, Cosimo; Szécsényi-Nagy, Anna; Rohland, Nadin; Mallick, Swapan; Olalde, Iñigo; Broomandkhoshbacht, Nasreen; Candilio, Francesca; Cheronet, Olivia; Fernandes, Daniel; Ferry, Matthew; Gamarra, Beatriz; Fortes, Gloria González; Haak, Wolfgang; Harney, Eadaoin; Jones, Eppie; Keating, Denise; Krause-Kyora, Ben; Kucukkalipci, Isil; Michel, Megan; Mittnik, Alissa; Nägele, Kathrin; Novak, Mario; Oppenheimer, Jonas; Patterson, Nick; Pfrengle, Saskia; Sirak, Kendra; Stewardson, Kristin; Vai, Stefania; Alexandrov, Stefan; Alt, Kurt W; Andreescu, Radian; Antonović, Dragana; Ash, Abigail; Atanassova, Nadezhda; Bacvarov, Krum; Gusztáv, Mende Balázs; Bocherens, Hervé; Bolus, Michael; Boroneanţ, Adina; Boyadzhiev, Yavor; Budnik, Alicja; Burmaz, Josip; Chohadzhiev, Stefan; Conard, Nicholas J; Cottiaux, Richard; Čuka, Maja; Cupillard, Christophe; Drucker, Dorothée G; Elenski, Nedko; Francken, Michael; Galabova, Borislava; Ganetsovski, Georgi; Gély, Bernard; Hajdu, Tamás; Handzhyiska, Veneta; Harvati, Katerina; Higham, Thomas; Iliev, Stanislav; Janković, Ivor; Karavanić, Ivor; Kennett, Douglas J; Komšo, Darko; Kozak, Alexandra; Labuda, Damian; Lari, Martina; Lazar, Catalin; Leppek, Maleen; Leshtakov, Krassimir; Vetro, Domenico Lo; Los, Dženi; Lozanov, Ivaylo; Malina, Maria; Martini, Fabio; McSweeney, Kath; Meller, Harald; Menđušić, Marko; Mirea, Pavel; Moiseyev, Vyacheslav; Petrova, Vanya; Price, T Douglas; Simalcsik, Angela; Sineo, Luca; Šlaus, Mario; Slavchev, Vladimir; Stanev, Petar; Starović, Andrej; Szeniczey, Tamás; Talamo, Sahra; Teschler-Nicola, Maria; Thevenet, Corinne; Valchev, Ivan; Valentin, Frédérique; Vasilyev, Sergey; Veljanovska, Fanica; Venelinova, Svetlana; Veselovskaya, Elizaveta; Viola, Bence; Virag, Cristian; Zaninović, Joško; Zäuner, Steve; Stockhammer, Philipp W; Catalano, Giulio; Krauß, Raiko; Caramelli, David; Zariņa, Gunita; Gaydarska, Bisserka; Lillie, Malcolm; Nikitin, Alexey G; Potekhina, Inna; Papathanasiou, Anastasia; Borić, Dušan; Bonsall, Clive; Krause, Johannes; Pinhasi, Ron; Reich, David

2018-03-08

Farming was first introduced to Europe in the mid-seventh millennium bc, and was associated with migrants from Anatolia who settled in the southeast before spreading throughout Europe. Here, to understand the dynamics of this process, we analysed genome-wide ancient DNA data from 225 individuals who lived in southeastern Europe and surrounding regions between 12000 and 500 bc. We document a west-east cline of ancestry in indigenous hunter-gatherers and, in eastern Europe, the early stages in the formation of Bronze Age steppe ancestry. We show that the first farmers of northern and western Europe dispersed through southeastern Europe with limited hunter-gatherer admixture, but that some early groups in the southeast mixed extensively with hunter-gatherers without the sex-biased admixture that prevailed later in the north and west. We also show that southeastern Europe continued to be a nexus between east and west after the arrival of farmers, with intermittent genetic contact with steppe populations occurring up to 2,000 years earlier than the migrations from the steppe that ultimately replaced much of the population of northern Europe.

Formation of magmatic brine lenses via focussed fluid-flow beneath volcanoes

Science.gov (United States)

Afanasyev, Andrey; Blundy, Jon; Melnik, Oleg; Sparks, Steve

2018-03-01

Many active or dormant volcanoes show regions of high electrical conductivity at depths of a few kilometres beneath the edifice. We explore the possibility that these regions represent lenses of high-salinity brine separated from a single-phase magmatic fluid containing H2O and NaCl. Since chloride-bearing fluids are highly conductive and have an exceptional capacity to transport metals, these regions can be an indication of an active hydrothermal ore-formation beneath volcanoes. To investigate this possibility we have performed hydrodynamic simulations of magma degassing into permeable rock. In our models the magma source is located at 7 km depth and the fluid salinity approximates that expected for fluids released from typical arc magmas. Our model differs from previous models of a similar process because it is (a) axisymmetric and (b) includes a static high-permeability pathway that links the magma source to the surface. This pathway simulates the presence of a volcanic conduit and/or plexus of feeder dykes that are typical of most volcanic systems. The presence of the conduit leads to a number of important hydrodynamic consequences, not observed in previous models. Importantly, we show that an annular brine lens capped by crystallised halite is likely to form above an actively degassing sub-volcanic magma body and can persist for more than 250 kyr after degassing ceases. Parametric analysis shows that brine lenses are more prevalent when the fluid is released at temperatures above the wet granite solidus, when magmatic fluid salinity is high, and when the high-permeability pathway is narrow. The calculated depth, form and electrical conductivity of our modelled system shares many features with published magnetotelluric images of volcano subsurfaces. The formation and persistence of sub-volcanic brine lenses has implications for geothermal systems and hydrothermal ore formation, although these features are not explored in the presented model.

Geodynamic Constraints on the Sources of Seismic Anisotropy Beneath Madagascar

Science.gov (United States)

Rajaonarison, T. A.; Stamps, D. S.; Fishwick, S.

2017-12-01

majority of the seismic anisotropy are due to sub-lithospheric asthenospheric flow beneath Madagascar. Our results suggest the dislocation creep regime extends beneath the lithosphere, which implies the rheology of the upper asthenosphere deforms by dislocation creep rather than diffusion creep.

Patterns of Macrozooplankton and Fish Occurrence Beneath McMurdo Sound Fast Ice during Spring/Summer 2014/2015

Science.gov (United States)

Saenz, B. T.; Daly, K. L.; Kim, S.; Ainley, D. G.; Ballard, G.

2016-02-01

McMurdo Sound, Antarctica, represents a unique environment for study of trophic interactions, where a full complement of marine predators thrive. As part of a greater study of McMurdo Sound food web interactions, including ocean and ice physics, algal characterization, and predator behavior, macrozooplankton and fish were surveyed using bioacoustics and video using a specially-designed under-ice ROV. Acoustic returns from 82 under-ice surveys were divided into classes consisting of krill, silverfish, and weak scatters. Krill were scarce during surveys in late November, but increased in abundance in association with increasing chlorophyll a in December and early January when surveys ended. The greatest concentrations of krill were found near Ross Island in the eastern Sound, where southerly currents move high-productivity waters beneath the fast ice. Conversely, silverfish, especially schools of juveniles, were found in greater abundance toward the west where currents flow northward and platelet ice typically blocked light from surface waters. Silverfish were rare toward the end of the survey in late December/early January, but possibly had moved deeper than the acoustic instrument could detect. Overall, krill were less abundant and occurred deeper in the water column within 2 km of the fast ice edge, which was accessible by air-breathing predators, suggesting that predation pressure helped structure krill abundance or distribution. Acoustic returns from weak scatters, which included observed jellies, pteropods, detached ice algae and potentially other mesoplankton in high abundance such as copepods, also increased during the study period and co-occurred with chlorophyll a. The patterns of macrozooplankton and fish observed in McMurdo Sound raise important questions about source-sink dynamics, overwinter strategies of mid-trophic organisms, prey-predator dynamics, and sea-ice structuring of ecosystems.

Crustal and Upper Mantle Velocity Structure beneath Northwestern South America revealed by the CARMArray

Science.gov (United States)

Miao, W.; Cornthwaite, J.; Levander, A.; Niu, F.; Schmitz, M.; Dionicio, V.; Nader-Nieto, M. F.

2017-12-01

The Caribbean plate (CAR) is a fragment of the Farallon plate heavily modified by igneous processes that created the Caribbean large igneous province (CLIP) between 110 and 80 Ma.The CAR collided with and initiated subduction beneath northwestern South America plate (SA) at about 60-55 Ma as a narrow flat-slab subduction zone with an accretionary prism offshore, but no volcanic arc. Large scale regional tomography suggests that 1000 km of the CAR has been subducted (Van Benthem et al., 2013, JGR). The flat slab has caused Laramide-style basement uplifts of the Merida Andes, Sierra de la Perija, and Santa Marta ranges with elevations >5 km. The details of subduction geometry of the CAR plate beneath northeastern Colombia and northwestern Venezuela are complicated and remain unclear. The region of slab steepening lies below the triangular Maracaibo block (Bezada et al, 2010, JGR), bounded by major strike slip faults and currently escaping to the north over the CAR. Geodetic data suggests the this region has the potential for a magnitude 8+ earthquake (Bilham and Mencin, 2013, AGU Abstract). To better understand the subduction geometry, we deployed 65 broadband (BB) stations across northeastern Colombia and northwestern Venezuela in April of 2016. The 65 stations interweave with the 32 existing Colombian and Venezuelan BB stations, forming a 2-D array (hereafter referred to as CARMArray) with a station spacing of 35-100 km that covers an area of 600 km by 400 km extending from the Caribbean coast in Colombia to the interior plains of Venezuela. With data from the first year of operation, we have measured the Rayleigh wave phase velocities and Z/H ratios in the period range of 8-40 s using both ambient noise and earthquake data recorded by the CARMArray. We also generated Ps receiver functions from waveform data of teleseismic events recorded by the array. We then jointly inverted the three datasets to construct a 3-D S-wave velocity model beneath the array. We will

Spatiotemporal throughfall patterns beneath an urban tree row

Science.gov (United States)

Bogeholz, P.; Van Stan, J. T., II; Hildebrandt, A.; Friesen, J.; Dibble, M.; Norman, Z.

2016-12-01

Much recent research has focused on throughfall patterns in natural forests as they can influence the heterogeneity of surface ecohydrological and biogeochemical processes. However, to the knowledge of the authors, no work has assessed how urban forest structures affect the spatiotemporal variability of throughfall water flux. Urbanization greatly alters not only a significant portion of the land surface, but canopy structure, with the most typical urban forest configuration being landscaped tree rows along streets, swales, parking lot medians, etc. This study examines throughfall spatiotemporal patterns for a landscaped tree row of Pinus elliottii (Engelm., slash pine) on Georgia Southern University's campus (southeastern, USA) using 150 individual observations per storm. Throughfall correlation lengths beneath this tree row were similar to, but appeared to be more stable across storm size than, observations in past studies on natural forests. Individual tree overlap and the planting interval also may more strongly drive throughfall patterns in tree rows. Meteorological influences beyond storm magnitude (intensity, intermittency, wind conditions, and atmospheric moisture demand) are also examined.

Stratigraphy of the late Cenozoic sediments beneath the 216-B and C crib facilities

International Nuclear Information System (INIS)

Fecht, K.R.; Last, G.V.; Marratt, M.C.

1979-02-01

The stratigraphy of the late Cenozoic sediments beneath the 216-B and C Crib Facilities is presented as lithofacies cross sections and is based on textural variations of the sedimentary sequence lying above the basalt bedrock. The primary source of data in this study is geologic information obtained from well drilling operations and geophysical logging. Stratigraphic interpretations are based primarily on textural analysis and visual examination of sediment samples and supplemented by drillers logs and geophysical logs

Melt zones beneath five volcanic complexes in California: an assessment of shallow magma occurrences

Energy Technology Data Exchange (ETDEWEB)

Goldstein, N.E.; Flexser, S.

1984-12-01

Recent geological and geophysical data for five magma-hydrothermal systems were studied for the purpose of developing estimates for the depth, volume and location of magma beneath each area. The areas studied were: (1) Salton Trough, (2) The Geysers-Clear Lake, (3) Long Valley caldera, (4) Coso volcanic field, and (5) Medicine Lake volcano, all located in California and all selected on the basis of recent volcanic activity and published indications of crustal melt zones. 23 figs.

Some possible applications of peaceful nuclear explosions in the recovery of natural resources from beneath the seabed

International Nuclear Information System (INIS)

Parker, K.

1975-01-01

The technical, economic and environmental advantages and disadvantages of using nuclear explosions as an aid to recovering natural resources from beneath the seabed are discussed and compared with those in applications on land. Particular consideration is given to their use in assisting petroleum production as offshore development moves into deeper waters. (author)

Occurrence and prevalence of selected zoonotic agents: Echinococcus multilocularis, Trichinella spiralis and hepatitis E virus (HEV) in the population of Polish hunters--results of the study conducted in 2010-2012.

Science.gov (United States)

Sadkowska-Todys, Małgorzata; Baumann-Popczyk, Anna; Wnukowska, Natalia; Popczyk, Bartłomiej; Kucharczyk, Bożena; Gołąb, Elżbieta

2015-01-01

In Poland the development of the knowledge concerning zoonotic pathogens, of which free-living animals are the reservoir of is gaining in importance both in epidemiological aspect as well as in the context of prevention for improving public health. Dietary habits such as the consumption of forest undergrowth products and wild game meat, and the way of those products being prepared (in the process of barbequing) pose a risk factors of infection with the foodborne pathogens such as Echinococcus multilocularis, Trichinella spp., and HEV. The aim of this study is to estimate the prevalence of infections caused by Trichinella spp., Echinococcus multilocularis, and HEV in the population of Polish hunters, describing their geographical distribution in Poland, and to try to define basic factors, which may contribute to their occurrence. In 2010-2012 a cross-sectional study was carried out among Polish hunters. A blood samples were collected as well as a survey of 1027 participants recruited in the 16 provinces was also carried out. Serological tests were performed for the presence of specific antibodies against Echinococcus multilocularis, Trichinella spp. and HEV using commercial or "in home" ELISA tests. In case of positive result for Echinococcus, an Em2plus ELISA or/and western blot test were carried out, and for positive results for IgM for HEV a recomLine HEV IgM test was carried out. In the studied population a total number of 2 cases of Echinococcus multilocularis infection were found. Moreover in 47 (4,6%) participants presence of antibodies against Trichinella spp. were found, including 17 positive and 30 borderline results. In 206 persons (25%) IgG anti-HEV antibodies were found (by ELISA test). Geographical diversity in prevalence of both, the Trichinella spp. and HEV cases was observed. The study confirmed presence of zoonotic infections such as Echinococcus multilocularis, Trichinella spp., and hepatitis E (HEV) among Polish hunters. In the case of

Nuclear wastes beneath the deep sea floor

International Nuclear Information System (INIS)

Bishop, W.P.; Hollister, C.D.

1974-01-01

Projections of energy demands for the year 2000 show that nuclear power will likely be one of our energy sources. But the benefits of nuclear power must be balanced against the drawbacks of its by-product: high-level wastes. While it may become possible to completely destroy or eliminate these wastes, it is at least equally possible that we may have to dispose of them on earth in such a way as to assure their isolation from man for periods of the order of a million years. Undersea regions in the middle of tectonic plates and in the approximate center of major current gyres offer some conceptual promise for waste disposal because of their geologic stability and comparatively low organic productivity. The advantages of this concept and the types of detailed information needed for its accurate assessment are discussed. The technical feasibility of permanent disposal beneath the deep sea floor cannot be accurately assessed with present knowledge, and there is a need for a thorough study of the types and rates of processes that affect this part of the earth's surface. Basic oceanographic research aimed at understanding these processes is yielding answers that apply to this societal need. (U.S.)

Mapping lithosphere thickness beneath the Southern Caribbean and Venezuela using body wave reflectivity and surface wave tomography

Science.gov (United States)

Masy, J.; Niu, F.; Levander, A.; Schmitz, M.

2012-12-01

lateral resolution (Yang and Forsyth, 2006). The phase velocities were inverted for 1D shear velocity structure on a 0.5 by 0.5 degree grid. Crustal thickness for the starting models was previously determined from BOLIVAR and other wide-angle seismic experiments and receiver function analysis (Schmitz et al., 2001; Niu et al., 2007; Bezada et al., 2007; Clark et al., 2008; Guedez, 2008; Magnani et al., 2009; Bezada et al., 2010a). The resulting 3D shear velocity model was then used to determine the depth of the LAB in conjunction with Ps and Sp receiver functions. LAB depth is approximately 120-140 km beneath the Archean-Proterozoic Guayana Shield, in reasonable agreement with body wave tomography. The lithosphere thins to the west beneath the Barinas Apure Basin to about 90 km, and to the north beneath the Sierra del Interior to 80 to 90 km. Offshore beneath the Cariaco basin the LAB is ~60 km. At depths up to 200 km beneath the Peninsula the Paria, there are high velocities interepreted as the subducting oceanic part of the South American Plate, a result that is consistent with finite-frequency P wave tomography (Bezada et al., 2010b).

Recent Discoveries of the Paijanense in The Upper Chicama, Moche and Virú Valleys, Northern Perú: New Perspectives on the First Hunter-Gatherers in the Andes of South America

OpenAIRE

Briceño, Jesús

2014-01-01

We present newly-registered Paiján sites in the interior and upper parts of the Chicama, Moche and Virú valleys, with strong tiesto the highland region. The research indicates that Paiján hunter-gatherers were not only a coastal group whose subsistence was basedon marine resources. They also occupied diverse ecological environments preferring springs with high mobility across the Andes and exploiting diverse resources, such as white-tail deer (Odocoileus virginianus) and raw materials for pro...

Short wavelength lateral variability of lithospheric mantle beneath the Middle Atlas (Morocco) as recorded by mantle xenoliths

Science.gov (United States)

El Messbahi, Hicham; Bodinier, Jean-Louis; Vauchez, Alain; Dautria, Jean-Marie; Ouali, Houssa; Garrido, Carlos J.

2015-05-01

The Middle Atlas is a region where xenolith-bearing volcanism roughly coincides with the maximum of lithospheric thinning beneath continental Morocco. It is therefore a key area to study the mechanisms of lithospheric thinning and constrain the component of mantle buoyancy that is required to explain the Moroccan topography. Samples from the two main xenolith localities, the Bou Ibalghatene and Tafraoute maars, have been investigated for their mineralogy, microstructures, crystallographic preferred orientation, and whole-rock and mineral compositions. While Bou Ibalghatene belongs to the main Middle Atlas volcanic field, in the 'tabular' Middle Atlas, Tafraoute is situated about 45 km away, on the North Middle Atlas Fault that separates the 'folded' Middle Atlas, to the South-East, from the 'tabular' Middle Atlas, to the North-West. Both xenolith suites record infiltration of sub-lithospheric melts that are akin to the Middle Atlas volcanism but were differentiated to variable degrees as a result of interactions with lithospheric mantle. However, while the Bou Ibalghatene mantle was densely traversed by high melt fractions, mostly focused in melt conduits, the Tafraoute suite records heterogeneous infiltration of smaller melt fractions that migrated diffusively, by intergranular porous flow. As a consequence the lithospheric mantle beneath Bou Ibalghaten was strongly modified by melt-rock interactions in the Cenozoic whereas the Tafraoute mantle preserves the record of extensional lithospheric thinning, most likely related to Mesozoic rifting. The two xenolith suites illustrate distinct mechanisms of lithospheric thinning: extensional thinning in Tafraoute, where hydrous incongruent melting triggered by decompression probably played a key role in favouring strain localisation, vs. thermal erosion in Bou Ibalghatene, favoured and guided by a dense network of melt conduits. Our results lend support to the suggestion that lithospheric thinning beneath the Atlas

Knowledge-Sharing Networks in Hunter-Gatherers and the Evolution of Cumulative Culture.

Science.gov (United States)

Salali, Gul Deniz; Chaudhary, Nikhil; Thompson, James; Grace, Olwen Megan; van der Burgt, Xander M; Dyble, Mark; Page, Abigail E; Smith, Daniel; Lewis, Jerome; Mace, Ruth; Vinicius, Lucio; Migliano, Andrea Bamberg

2016-09-26

Humans possess the unique ability for cumulative culture [1, 2]. It has been argued that hunter-gatherer's complex social structure [3-9] has facilitated the evolution of cumulative culture by allowing information exchange among large pools of individuals [10-13]. However, empirical evidence for the interaction between social structure and cultural transmission is scant [14]. Here we examine the reported co-occurrence of plant uses between individuals in dyads (which we define as their "shared knowledge" of plant uses) in BaYaka Pygmies from Congo. We studied reported uses of 33 plants of 219 individuals from four camps. We show that (1) plant uses by BaYaka fall into three main domains: medicinal, foraging, and social norms/beliefs; (2) most medicinal plants have known bioactive properties, and some are positively associated with children's BMI, suggesting that their use is adaptive; (3) knowledge of medicinal plants is mainly shared between spouses and biological and affinal kin; and (4) knowledge of plant uses associated with foraging and social norms is shared more widely among campmates, regardless of relatedness, and is important for camp-wide activities that require cooperation. Our results show the interdependence between social structure and knowledge sharing. We propose that long-term pair bonds, affinal kin recognition, exogamy, and multi-locality create ties between unrelated families, facilitating the transmission of medicinal knowledge and its fitness implications. Additionally, multi-family camps with low inter-relatedness between camp members provide a framework for the exchange of functional information related to cooperative activities beyond the family unit, such as foraging and regulation of social life. Copyright © 2016 Elsevier Ltd. All rights reserved.

Formation of heterogeneous magmatic series beneath North Santorini, South Aegean island arc

DEFF Research Database (Denmark)

Bailey, John C; Jensen, E.S.; Hansen, A.

2008-01-01

magma formation beneath North Santorini throughout its 500 ka history is attributed to variable transfer of sedimentary components - either terrigenous or pelagic, as bulk sediments or high-temperature partial melts rather than fluids or low-temperature partial melts - from a rupture zone...... in the subducted slab to the overlying mantle. The three main magmatic series followed independent paths of assimilation of upper crustal materials during fractional crystallization. Assimilation was more pronounced at the basaltic stage. The long-lived histories of the three main magmatic series imply repetitive...... melting of isolated mantle regions, ascent of magmas through independent feeder systems, and their residence in separate crustal magma chambers....

Uranium potential in outcropping Permian basins in France and their extensions beneath mesozoic and tertiary cover

International Nuclear Information System (INIS)

Hery, B.

1990-01-01

About a third of metropolitan France's uranium production is from Permian deposits located in the Lodeve and, to a lesser extent, Bourbon-l'Archambault basins. Of the Autun, west Vanoise, St-Affrique, Rodez, Brive and Var basins investigated in this study, only those of Rodez and Var have been shown to contain significant deposits. Some of the basins contain potentially interesting targets, often removed from the areas of known mineral occurrences, that have never been investigated. Geophysical exploration and drilling have shown that the Permian extends over a vast area beneath the cover of the large Mesozoic and Tertiary basins. However zones within reach of mineral exploration, ie. those less than 500 m deep, are only found in a few areas. To reach the distant targets down-dip in the outcropping basins or beneath the Mesozoic and Tertiary cover, a detailed study of the basin must be undertaken beforehand. To define and locate targets that are obviously more costly to investigate, direct methods of investigation need to be used such as drilling and geochemistry, and indirect methods such as remote sensing, geophysics and well-logging [fr

New Crustal Boundary Revealed Beneath the Ross Ice Shelf, Antarctica, through ROSETTA-Ice Integrated Aerogeophysics, Geology, and Ocean Research

Science.gov (United States)

Tinto, K. J.; Siddoway, C. S.; Bell, R. E.; Lockett, A.; Wilner, J.

2017-12-01

Now submerged within marine plateaus and rises bordering Antarctica, Australia and Zealandia, the East Gondwana accretionary margin was a belt of terranes and stitched by magmatic arcs, later stretched into continental ribbons separated by narrow elongate rifts. This crustal architecture is known from marine geophysical exploration and ocean drilling of the mid-latitude coastal plateaus and rises. A concealed sector of the former East Gondwana margin that underlies the Ross Ice Shelf (RIS), Antarctica, is the focus of ROSETTA-ICE, a new airborne data acquisition campaign that explores the crustal makeup, tectonic boundaries and seafloor bathymetry beneath RIS. Gravimeters and a magnetometer are deployed by LC130 aircraft surveying along E-W lines spaced at 10 km, and N-S tie lines at 55 km, connect 1970s points (RIGGS) for controls on ocean depth and gravity. The ROSETTA-ICE survey, 2/3 completed thus far, provides magnetic anomalies, Werner depth-to-basement solutions, a new gravity-based bathymetric model at 20-km resolution, and a new crustal density map tied to the 1970s data. Surprisingly, the data reveal that the major lithospheric boundary separating East and West Antarctica lies 300 km east of the Transantarctic Mountains, beneath the floating RIS. The East and West regions have contrasting geophysical characteristics and bathymetry, with relatively dense lithosphere, low amplitude magnetic anomalies, and deep bathymetry on the East Antarctica side, and high amplitude magnetic anomalies, lower overall density and shallower water depths on the West Antarctic side. The Central High, a basement structure cored at DSDP Site 270 and seismically imaged in the Ross Sea, continues beneath RIS as a faulted but coherent crustal ribbon coincident with the tectonic boundary. The continuity of Gondwana margin crustal architecture discovered beneath the West Antarctic Ice Sheet requires a revision of the existing tectonic framework. The sub-RIS narrow rift basins and

Lateral Variations of the Mantle Transition Zone Structure beneath the Southeastern Tibetan Plateau Revealed by P-wave Receiver Functions

Science.gov (United States)

Bai, Y.; Ai, Y.; Jiang, M.; He, Y.; Chen, Q.

2017-12-01

The deep structure of the southeastern Tibetan plateau is of great scientific importance to a better understanding of the India-Eurasia collision as well as the evolution of the magnificent Tibetan plateau. In this study, we collected 566 permanent and temporary seismic stations deployed in SE Tibet, with a total of 77853 high quality P-wave receiver functions been extracted by maximum entropy deconvolution method. On the basis of the Common Conversion Point (CCP) stacking technique, we mapped the topography of the 410km and 660km discontinuities (hereinafter called the `410' and the `660'), and further investigated the lateral variation of the mantle transition zone (MTZ) thickness beneath this region. The background velocity model deduced from H-κ stacking results and a previous body-wave tomographic research was applied for the correction of the crustal and upper mantle heterogeneities beneath SE Tibet for CCP stacking. Our results reveal two significantly thickened MTZ anomalies aligned nearly in the south-north direction. The magnitude of both anomalies are 30km above the global average of 250km. The southern anomaly located beneath the Dianzhong sub-block and the Indo-China block is characterized by a slightly deeper `410' and a greater-than-normal `660', while the northern anomaly beneath western Sichuan has an uplifted `410' and a depressed `660'. Combining with previous studies in the adjacent region, we suggest that slab break-off may occurred during the eastward subduction of the Burma plate, with the lower part of the cold slab penetrated into the MTZ and stagnated at the bottom of the `660' which may cause the southern anomaly in our receiver function images. The origin of the Tengchong volcano is probably connected to the upwelling of the asthenospheric material caused by the slab break-off or to the ascending of the hot and wet material triggered by the dehydration of stagnant slab in the MTZ. The anomaly in the north, on the other hand, might be

Quantitative autoradiographic localization of cholecystokinin receptors in rat and guinea pig brain using 125I-Bolton-Hunter-CCK8

International Nuclear Information System (INIS)

Niehoff, D.L.

1989-01-01

The autoradiographic localization of receptors for the brain-gut peptide cholecystokinin (CCK) has shown differences in receptor distribution between rat and guinea pig brain. However the full anatomical extent of the differences has not been determined quantitatively. In the present study, 125 I-Bolton-Hunter-CCK8 ( 125 I-BH-CCK8) was employed in a comparative quantitative autoradiographic analysis of the distribution of CCK receptors in these two species. The pharmacological profile of 125 I-BH-CCK8 binding in guinea pig forebrain sections was comparable to those previously reported for rat and human. Statistically significant differences in receptor binding between rat and guinea pig occurred in olfactory bulb, caudate-putamen, amygdala, several cortical areas, ventromedial hypothalamus, cerebellum, and a number of midbrain and brainstem nuclei. The results of this study confirm the presence of extensive species-specific variation in the distribution of CCK receptors, suggesting possible differences in the physiological roles of this peptide in different mammalian species

Ancient genomes show social and reproductive behavior of early Upper Paleolithic foragers

DEFF Research Database (Denmark)

Sikora, Martin; Seguin-Orlando, Andaine; Sousa, Vitor C.

2017-01-01

Present-day hunter-gatherers (HGs) live in multilevel social groups essential to sustain a population structure characterized by limited levels of within-band relatedness and inbreeding. When these wider social networks evolved among HGs is unknown. Here, we investigate whether the contemporary H...

New constraints on the textural and geochemical evolution of the upper mantle beneath the Styrian basin

Science.gov (United States)

Aradi, Laszlo; Hidas, Károly; Zanetti, Alberto; János Kovács, István; Patkó, Levente; Szabó, Csaba

2016-04-01

Plio-Pleistocene alkali basaltic volcanism sampled sporadically the upper mantle beneath the Carpathian-Pannonian Region (CPR, e.g. [1]). Lavas and pyroclasts often contain mantle derived xenoliths, and the majority of them have been extensively studied [1], except the westernmost Styrian Basin Volcanic Field (SBVF, Eastern Austria and Slovenia). In the SBVF only a few volcanic centers have been studied in details (e.g. Kapfenstein & Tobaj). Based on these studies, the upper mantle beneath the SBVF is consists of dominantly high temperature, texturally and geochemically homogeneous protogranular spinel lherzolite. New major and trace element data from rock-forming minerals of ultramafic xenoliths, coupled with texture and deformation analysis from 12 volcanic outcrops across the SBVF, suggest that the lithospheric roots of the region are more heterogeneous than described previously. The studied xenoliths are predominantly lherzolite, amphibole is a common phase that replaces pyroxenes and spinels and proves modal metasomatism. Phlogopite coupled with apatite is also present in amphibole-rich samples. The texture of the xenoliths is usually coarse-grained and annealed with low abundance of subgrain boundaries in both olivine and pyroxenes. Olivine crystal preferred orientation (CPO) varies between the three most abundant one: [010]-fiber, orthogonal and [100]-fiber symmetry [2]. The CPO of pyroxenes is usually coherent with coeval deformation with olivine, however the CPO of amphibole is suggesting postkinematic epitaxial overgrowth on the precursor pyroxenes. According to equilibrium temperatures, the studied xenolith suite samples a broader temperature range (850-1100 °C) than the literature data, corresponding to mantle depths between 30 and 60 km, which indicates that the xenolith suite only represents the shallower part of the recent 100 km thick lithospheric mantle beneath the SBVF. The equilibrium temperatures show correlation with the varying CPO symmetries

Finite-Frequency Seismic Tomography of Body Waves and Surface Waves from Ambient Seismic Noise: Crustal and Mantle Structure Beneath Eastern Eurasia

National Research Council Canada - National Science Library

Ren, Yong; Zhang, Wei; Yang, Ting; Shen, Yang; Yang, Xiaoping

2008-01-01

To improve seismic calibration for nuclear explosion monitoring, we use 3D sensitivity kernels of finite-frequency body and surface waves to develop models of the crustal and mantle structures beneath eastern Eurasia...

Simulation of Groundwater Mounding Beneath Hypothetical Stormwater Infiltration Basins

Science.gov (United States)

Carleton, Glen B.

2010-01-01

Groundwater mounding occurs beneath stormwater management structures designed to infiltrate stormwater runoff. Concentrating recharge in a small area can cause groundwater mounding that affects the basements of nearby homes and other structures. Methods for quantitatively predicting the height and extent of groundwater mounding beneath and near stormwater Finite-difference groundwater-flow simulations of infiltration from hypothetical stormwater infiltration structures (which are typically constructed as basins or dry wells) were done for 10-acre and 1-acre developments. Aquifer and stormwater-runoff characteristics in the model were changed to determine which factors are most likely to have the greatest effect on simulating the maximum height and maximum extent of groundwater mounding. Aquifer characteristics that were changed include soil permeability, aquifer thickness, and specific yield. Stormwater-runoff variables that were changed include magnitude of design storm, percentage of impervious area, infiltration-structure depth (maximum depth of standing water), and infiltration-basin shape. Values used for all variables are representative of typical physical conditions and stormwater management designs in New Jersey but do not include all possible values. Results are considered to be a representative, but not all-inclusive, subset of likely results. Maximum heights of simulated groundwater mounds beneath stormwater infiltration structures are the most sensitive to (show the greatest change with changes to) soil permeability. The maximum height of the groundwater mound is higher when values of soil permeability, aquifer thickness, or specific yield are decreased or when basin depth is increased or the basin shape is square (and values of other variables are held constant). Changing soil permeability, aquifer thickness, specific yield, infiltration-structure depth, or infiltration-structure shape does not change the volume of water infiltrated, it changes the

Density contrast across the Moho beneath the Indian shield: Implications for isostasy

Science.gov (United States)

Paul, Himangshu; Mangalampally, Ravi Kumar; Tiwari, Virendra Mani; Singh, Arun; Chadha, Rajender Kumar; Davuluri, Srinagesh

2018-04-01

Knowledge of isostasy provides insights into how excess (or deficit) of mass on and within the lithosphere is maintained over different time scales, and also helps decipher the vertical dynamics. In continental regions, isostasy is primarily manifested as a crustal root, the extent of which is defined by the lithospheric strength and the density contrast at the Moho. In this study, we briefly review the methodology for extracting the density contrast across the Moho using the amplitudes of the P-to-s converted and free-surface reverberating phases in a receiver function (RF). We test the efficacy of this technique by applying it on synthetic and real data from 10 broadband seismic stations sited on diverse tectonic provinces in the Indian shield. We determine the density contrast after parameterizing the shear-wave velocity structure beneath the stations using the nearest neighbourhood algorithm. We find considerable variation in the density contrast across the Moho beneath the stations (0.4-0.65 gm/cc). This is explained in terms of isostatic compensation, incorporating the existing estimates of lithospheric strength (Te). Crustal roots computed using the estimated Te and the deduced density contrast substantiate the crustal thickness values inferred through RF analysis, and vice versa. This illustrates isostasy as a combination of variation in density contrast and Te. The density contrasts and crustal thicknesses inferred from RF analysis explain well the isostatic compensation mechanism in different regions. However, unusually large density contrasts (∼0.6 gm/cc) corresponding to elevated regions are intriguing and warrant further investigations. Our observation of varied density contrasts at the Moho in a Precambrian continental setting is interesting and raises a question about the existence of such situations in other parts of the world.

Upper Mantle Shear Wave Structure Beneath North America From Multi-mode Surface Wave Tomography

Science.gov (United States)

Yoshizawa, K.; Ekström, G.

2008-12-01

The upper mantle structure beneath the North American continent has been investigated from measurements of multi-mode phase speeds of Love and Rayleigh waves. To estimate fundamental-mode and higher-mode phase speeds of surface waves from a single seismogram at regional distances, we have employed a method of nonlinear waveform fitting based on a direct model-parameter search using the neighbourhood algorithm (Yoshizawa & Kennett, 2002). The method of the waveform analysis has been fully automated by employing empirical quantitative measures for evaluating the accuracy/reliability of estimated multi-mode phase dispersion curves, and thus it is helpful in processing the dramatically increasing numbers of seismic data from the latest regional networks such as USArray. As a first step toward modeling the regional anisotropic shear-wave velocity structure of the North American upper mantle with extended vertical resolution, we have applied the method to long-period three-component records of seismic stations in North America, which mostly comprise the GSN and US regional networks as well as the permanent and transportable USArray stations distributed by the IRIS DMC. Preliminary multi-mode phase-speed models show large-scale patterns of isotropic heterogeneity, such as a strong velocity contrast between the western and central/eastern United States, which are consistent with the recent global and regional models (e.g., Marone, et al. 2007; Nettles & Dziewonski, 2008). We will also discuss radial anisotropy of shear wave speed beneath North America from multi-mode dispersion measurements of Love and Rayleigh waves.

Schooling, Local Knowledge and Working Memory: A Study among Three Contemporary Hunter-Gatherer Societies.

Science.gov (United States)

Reyes-García, Victoria; Pyhälä, Aili; Díaz-Reviriego, Isabel; Duda, Romain; Fernández-Llamazares, Álvaro; Gallois, Sandrine; Guèze, Maximilien; Napitupulu, Lucentezza

2016-01-01

Researchers have analysed whether school and local knowledge complement or substitute each other, but have paid less attention to whether those two learning models use different cognitive strategies. In this study, we use data collected among three contemporary hunter-gatherer societies with relatively low levels of exposure to schooling yet with high levels of local ecological knowledge to test the association between i) schooling and ii) local ecological knowledge and verbal working memory. Participants include 94 people (24 Baka, 25 Punan, and 45 Tsimane') from whom we collected information on 1) schooling and school related skills (i.e., literacy and numeracy), 2) local knowledge and skills related to hunting and medicinal plants, and 3) working memory. To assess working memory, we applied a multi-trial free recall using words relevant to each cultural setting. People with and without schooling have similar levels of accurate and inaccurate recall, although they differ in their strategies to organize recall: people with schooling have higher results for serial clustering, suggesting better learning with repetition, whereas people without schooling have higher results for semantic clustering, suggesting they organize recall around semantically meaningful categories. Individual levels of local ecological knowledge are not related to accurate recall or organization recall, arguably due to overall high levels of local ecological knowledge. While schooling seems to favour some organization strategies this might come at the expense of some other organization strategies.

Schooling, Local Knowledge and Working Memory: A Study among Three Contemporary Hunter-Gatherer Societies.

Directory of Open Access Journals (Sweden)

Victoria Reyes-García

Full Text Available Researchers have analysed whether school and local knowledge complement or substitute each other, but have paid less attention to whether those two learning models use different cognitive strategies. In this study, we use data collected among three contemporary hunter-gatherer societies with relatively low levels of exposure to schooling yet with high levels of local ecological knowledge to test the association between i schooling and ii local ecological knowledge and verbal working memory. Participants include 94 people (24 Baka, 25 Punan, and 45 Tsimane' from whom we collected information on 1 schooling and school related skills (i.e., literacy and numeracy, 2 local knowledge and skills related to hunting and medicinal plants, and 3 working memory. To assess working memory, we applied a multi-trial free recall using words relevant to each cultural setting. People with and without schooling have similar levels of accurate and inaccurate recall, although they differ in their strategies to organize recall: people with schooling have higher results for serial clustering, suggesting better learning with repetition, whereas people without schooling have higher results for semantic clustering, suggesting they organize recall around semantically meaningful categories. Individual levels of local ecological knowledge are not related to accurate recall or organization recall, arguably due to overall high levels of local ecological knowledge. While schooling seems to favour some organization strategies this might come at the expense of some other organization strategies.

Clinical response to long term enzyme replacement treatment in children, adolescent and adult patients with Hunter syndrome.

Science.gov (United States)

Dalmau Serra, Jaime; Vitoria Miñana, Isidro; Calderón Fernández, Rafael; Cortell Aznar, Isidoro

2015-11-06

Since enzyme replacement treatment (ERT) with idursulfase is available for Hunter syndrome (HS; mucopolysaccharidosis type II), for the first time, disease progression can be limited and organ damage reduced or prevented. We described retrospectively the clinical evolution of eight HS males, treated with ERT and followed in routine clinical practice in Hospital Infantil La Fe (Valencia, Spain). We studied three children, three adolescents and two adults. Time from diagnosis to ERT ranged from 13.7 to 0.2 years, and duration of ERT ranged from 24 to 77.1 months. From the start of ERT, weight and height increased in children and adolescents and remained stable in adults. Glycosaminoglycans (GAG) decreased in all patients; in patient 5 (aged 23 years), we observed the highest reduction (86%) with recovery of carpal tunnel syndrome, splenomegaly and a decrease in nocturnal oxygen dependence. Our results show that ERT improve respiratory impairment and organomegalies and decrease GAGs levels in all patients including children, adolescent and adults. While cardiac manifestations and facial features stabilized, responses in other parameters were heterogeneous. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

Detrital zircon ages in Buller and Takaka terranes, New Zealand : constraints on early Zealandia history

International Nuclear Information System (INIS)

Adams, C.J.; Mortimer, N.; Campbell, H.J.; Griffin, W.L.

2015-01-01

Detrital zircon ages are presented for 34 early Palaeozoic sandstones from Buller and Takaka terranes, New Zealand, and formerly adjacent parts of Australia-Antarctica. The Buller-Takaka datasets always have two major groups: Ordovician-late Neoproterozoic, 444-700 Ma (but mainly 540-700 Ma), termed 'Gondwana Assembly' (GA), and early Neoproterozoic-Mesoproterozoic, 700-1600 Ma (but mainly 900-1200 Ma), termed 'Rodinia Assembly' (RA). In both terranes, significant age components within these groups are strikingly similar and also have RA/GA ratios, 0.6-1.8. The Cambrian volcanic arc of the Takaka Terrane has contributed little to the zircon patterns. Proportions of Late Cambrian-Early Ordovician zircons, characteristic of granitoid sources in the Ross-Delamerian Orogen are low. The zircons are predominantly reworked with contemporary zircons only evident in a few Buller datasets. The zircon patterns suggest that two major sources (late Mesoproterozoic and late Neoproterozoic), enduring over 120 Ma, were widely distributed and it is postulated they form Precambrian basement beneath southern Zealandia. (author).

Heart Failure Hospitalisations in the Hunter New England Area Over 10 years. A Changing Trend.

Science.gov (United States)

Al-Omary, Mohammed S; Davies, Allan J; Khan, Arshad A; McGee, Michael; Bastian, Bruce; Leitch, James; Attia, John; Fletcher, Peter J; Boyle, Andrew J

2017-06-01

Heart failure carries a major burden on our health system, mainly related to the high rate of hospital admission. An understanding of the recent trends in heart failure hospitalisation is essential to the future allocation of health resources. Our aim is to analyse the temporal trends in heart failure hospitalisation. We extracted all separations in the Hunter New England Local Health District between 2005-2014 (n=40,119) with an ICD 10 code for heart failure (I-50) in the first four diagnoses on discharge. The numbers of hospitalisations were age-standardised to the 2001 Australian population and compared based on gender and remoteness. There was a decline in the age-standardised hospitalisation. However, there was a clear inflection point between 2009-2010, after which the decline levelled off. The absolute number of hospitalisations increased between 2010 and 2014. Heart failure hospitalisation was higher in males compared to females and rural compared to metropolitan inhabitants. The gains in heart failure treatment noted in recent years seem to have come to an end. Patients aged 75 years and older are contributing the majority of age-standardised hospitalisations. Copyright © 2016 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Coupled Geochemical and Hydrological Processes Governing the Fate and Transport of Radionuclides and Toxic Metals Beneath the Hanford Tank Farms

International Nuclear Information System (INIS)

Scott Fendorf; Phil Jardine

2006-01-01

The goal of this research was to provide an improved understanding and predictive capability of coupled hydrological and geochemical mechanisms that are responsible for the accelerated migration and immobilization of radionuclides and toxic metals in the vadose zone beneath the Hanford Tank Farms

The soil moisture regimes beneath forest and an agricultural crop in southern India--Measurement and modelling

International Nuclear Information System (INIS)

Harding, R.J.; Hall, R.L.; Swaminath, M.H.; Murthy, K.V.

1992-01-01

The environmental effects of plantations of fast growing tree species has been a subject of some controversy in recent years. Extensive soil moisture measurements were made at three sites in Karnataka, southern India. At each site measurements were made beneath a number of vegetation types. These included fast growing tree species (Eucalyptus, Casuarina and Leucaena), degraded natural forest and an agricultural crop (ragi). The measurements indicate that beneath mature forest the available soil water is exhausted towards the end of the dry season, usually by March. The soil only becomes completely wetted if the subsequent monsoon has above average rainfall; during the weak monsoon of 1989 the soil remained approximately 150 mm below field capacity. After the monsoon (and during breaks in the monsoon) soil moisture depletion is between three and five mm per day. This rate decreases as the soil drys out. All the mature forest types show a similar soil water regime. This contrasts strongly with that of the agricultural crop, which shows much smaller changes. A range of soil water accounting models was applied to these data. The most successful are those which use the Penman formulation to estimate the potential evaporation and include a two-layer soil water depletion model. The more general Penman-Monteith formulation was also tested

Climate-driven environmental changes around 8,200 years ago favoured increases in cetacean strandings and Mediterranean hunter-gatherers exploited them.

Science.gov (United States)

Mannino, Marcello A; Talamo, Sahra; Tagliacozzo, Antonio; Fiore, Ivana; Nehlich, Olaf; Piperno, Marcello; Tusa, Sebastiano; Collina, Carmine; Di Salvo, Rosaria; Schimmenti, Vittoria; Richards, Michael P

2015-11-17

Cetacean mass strandings occur regularly worldwide, yet the compounded effects of natural and anthropogenic factors often complicate our understanding of these phenomena. Evidence of past stranding episodes may, thus, be essential to establish the potential influence of climate change. Investigations on bones from the site of Grotta dell'Uzzo in North West Sicily (Italy) show that the rapid climate change around 8,200 years ago coincided with increased strandings in the Mediterranean Sea. Stable isotope analyses on collagen from a large sample of remains recovered at this cave indicate that Mesolithic hunter-gatherers relied little on marine resources. A human and a red fox dating to the 8.2-kyr-BP climatic event, however, acquired at least one third of their protein from cetaceans. Numerous carcasses should have been available annually, for at least a decade, to obtain these proportions of meat. Our findings imply that climate-driven environmental changes, caused by global warming, may represent a serious threat to cetaceans in the near future.

Quantitative autoradiographic localization of cholecystokinin receptors in rat and guinea pig brain using sup 125 I-Bolton-Hunter-CCK8

Energy Technology Data Exchange (ETDEWEB)

Niehoff, D.L. (Abbott Laboratories, Abbott Park, IL (USA))

1989-03-01

The autoradiographic localization of receptors for the brain-gut peptide cholecystokinin (CCK) has shown differences in receptor distribution between rat and guinea pig brain. However the full anatomical extent of the differences has not been determined quantitatively. In the present study, {sup 125}I-Bolton-Hunter-CCK8 ({sup 125}I-BH-CCK8) was employed in a comparative quantitative autoradiographic analysis of the distribution of CCK receptors in these two species. The pharmacological profile of {sup 125}I-BH-CCK8 binding in guinea pig forebrain sections was comparable to those previously reported for rat and human. Statistically significant differences in receptor binding between rat and guinea pig occurred in olfactory bulb, caudate-putamen, amygdala, several cortical areas, ventromedial hypothalamus, cerebellum, and a number of midbrain and brainstem nuclei. The results of this study confirm the presence of extensive species-specific variation in the distribution of CCK receptors, suggesting possible differences in the physiological roles of this peptide in different mammalian species.

Sequence of deep-focus earthquakes beneath the Bonin Islands identified by the NIED nationwide dense seismic networks Hi-net and F-net

Science.gov (United States)

Takemura, Shunsuke; Saito, Tatsuhiko; Shiomi, Katsuhiko

2017-03-01

An M 6.8 ( Mw 6.5) deep-focus earthquake occurred beneath the Bonin Islands at 21:18 (JST) on June 23, 2015. Observed high-frequency (>1 Hz) seismograms across Japan, which contain several sets of P- and S-wave arrivals for the 10 min after the origin time, indicate that moderate-to-large earthquakes occurred sequentially around Japan. Snapshots of the seismic energy propagation illustrate that after one deep-focus earthquake occurred beneath the Sea of Japan, two deep-focus earthquakes occurred sequentially after the first ( Mw 6.5) event beneath the Bonin Islands in the next 4 min. The United States Geological Survey catalog includes three Bonin deep-focus earthquakes with similar hypocenter locations, but their estimated magnitudes are inconsistent with seismograms from across Japan. The maximum-amplitude patterns of the latter two earthquakes were similar to that of the first Bonin earthquake, which indicates similar locations and mechanisms. Furthermore, based on the ratios of the S-wave amplitudes to that of the first event, the magnitudes of the latter events are estimated as M 6.5 ± 0.02 and M 5.8 ± 0.02, respectively. Three magnitude-6-class earthquakes occurred sequentially within 4 min in the Pacific slab at 480 km depth, where complex heterogeneities exist within the slab.[Figure not available: see fulltext.

Seismic Evidence for the North China Plate Underthrusting Beneath Northeastern Tibet and its Implications for Plateau Growth

Science.gov (United States)

Ye, Z.; Gao, R.; Li, Q.; Zhang, H.

2016-12-01

The effects of India-Asia collision and the subsequent interaction between the two continents on northeastern Tibet (NE Tibet), i.e., the tectonic transition zone between the Tibetan plateau and the North China craton (NCC) for example, remain uncertain due to inadequate geophysical data coverage in NE Tibet. Here in this research, based on new dataset collected from a dense linear array of 38 broadband seismograph stations, we applied seismic receiver functions (Sp and Ps converted waves) to imaging the lithospheric structure and shear wave splitting (XKS waves) to inspecting the anisotropy in the lithosphere and upper mantle beneath NE Tibet. The seismic array traverses NE Tibet to the westernmost NCC (Alxa block) in an SSW-NNE direction. The lithosphere-asthenosphere boundary (LAB) is clearly defined and appears as a south-dipping interface that runs continuously from the Alxa interior to the Qilian orogen on the S-wave receiver function images. Shear wave splitting measurements show significant lateral variations of seismic anisotropy across NE Tibet. Under joint constraints from both the lithospheric structure imaging and the regional anisotropic regime, combined with previous studies and through a thorough analysis/comparison/integration, we finally constructed a comprehensive lithospheric model of NE Tibet. The model tells that the NCC lithospheric mantle has been persistently underthrust beneath the Qilian orogen in response to on-going convergence/compression between the interior Tibetan plateau and the NCC. This process forms the syntectonic crustal thrust. The regional anisotropic regime can be well accommodated in our interpretation. The lithospheric model summarized here can be well accommodated in a scenario of northeastward migration of stepwise/multiple Aisan mantle lithosphere underthrusting beneath the Tibetan plateau. The multiple Aisan lithospheric blocks underthrust the plateau stepwise in small scale. Our results provide a new section from

Macronutrient contributions of insects to the diets of hunter-gatherers: a geometric analysis.

Science.gov (United States)

Raubenheimer, David; Rothman, Jessica M; Pontzer, Herman; Simpson, Stephen J

2014-06-01

We present a geometric model for examining the macronutrient contributions of insects in the diets of pre-agricultural humans, and relate the findings to some contemporary societies that regularly eat insects. The model integrates published data on the macronutrient composition of insects and other foods in the diets of humans, recommended human macronutrient intakes, and estimated macronutrient intakes to examine the assumption that insects provided to pre-agricultural humans an invertebrate equivalent of vertebrate-derived meats, serving primarily as a source of protein. Our analysis suggests that insects vary more widely in their macronutrient content than is likely to be the case for most wild vertebrate meats, spanning a broad range of protein, fat and carbohydrate concentrations. Potentially, therefore, in terms of their proportional macronutrient composition, insects could serve as equivalents not only of wild meat, but of a range of other foods including some shellfish, nuts, pulses, vegetables and even fruits. Furthermore, humans might systematically manipulate the composition of edible insects to meet specific needs through pre-ingestive processing, such as cooking and selective removal of body parts. We present data suggesting that in modern societies for which protein is the more limiting macronutrient, pre-ingestive processing of edible insects might serve to concentrate protein. It is likely, however, that the dietary significance of insects was different for Paleolithic hunter-gatherers who were more limited in non-protein energy. Our conclusions are constrained by available data, but highlight the need for further studies, and suggest that our model provides an integrative framework for conceiving these studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

Origin and evolution of the deep thermochemical structure beneath Eurasia.

Science.gov (United States)

Flament, N; Williams, S; Müller, R D; Gurnis, M; Bower, D J

2017-01-18

A unique structure in the Earth's lowermost mantle, the Perm Anomaly, was recently identified beneath Eurasia. It seismologically resembles the large low-shear velocity provinces (LLSVPs) under Africa and the Pacific, but is much smaller. This challenges the current understanding of the evolution of the plate-mantle system in which plumes rise from the edges of the two LLSVPs, spatially fixed in time. New models of mantle flow over the last 230 million years reproduce the present-day structure of the lower mantle, and show a Perm-like anomaly. The anomaly formed in isolation within a closed subduction network ∼22,000 km in circumference prior to 150 million years ago before migrating ∼1,500 km westward at an average rate of 1 cm year -1 , indicating a greater mobility of deep mantle structures than previously recognized. We hypothesize that the mobile Perm Anomaly could be linked to the Emeishan volcanics, in contrast to the previously proposed Siberian Traps.

An appraisal of the geologic structure beneath the Ikogosi warm spring in south-western Nigeria using integrated surface geophysical methods

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J.S Ojo

2011-06-01

Full Text Available An integrated surface geophysical investigation involving resistivity and magnetic methods was carried out in the immediate vicinity of the Ikogosi warm spring situated in south-western Nigeria with a view to delineating its subsurface geological sequence and evaluating the structural setting beneath the warmspring. Total field magnetic measurements and vertical electrical sounding (VES data were acquired along five N-S traverses. Magnetic and VES data interpretation
involved inverse modelling. The inverse magnetic models delineated fractured quartzite/faulted areas within fresh massive quartzite at varying depths and beneath all traverses. The geoelectrical sections developed from VESinterpretation results also delineated a subsurface sequence consisting of a topsoil/weathered layer, fresh quartzite, fractured/faulted quartzite and fresh quartzite bedrock. It was deduced that the fractured/faulted quartzite may have acted as conduit for the
movement of warm groundwater from profound depths to the surface while the spring outlet was located on a geological interface  (lineament.

Thermal classification of lithospheric discontinuities beneath USArray

Science.gov (United States)

Hansen, Steven M.; Dueker, Ken; Schmandt, Brandon

2015-12-01

Broadband seismic data from the United States were processed into Ps and Sp receiver function image volumes for the purpose of constraining negative velocity gradients (NVG) at depths between the Moho and 200 km. Moho depth picks from the two independent datasets are in good agreement, however, large discrepancies in NVG picks occur and are attributed to free-surface multiples which obscure deep NVG arrivals in the Ps data. From the Sp data, shallow NVG are found west of the Rockies and in the central US while deep and sporadic NVG are observed beneath the Great Plains and northern Rockies. To aid the interpretation of the observed NVG arrivals, the mantle thermal field is estimated by mapping surface wave tomography velocities to temperature assuming an anelastic olivine model. The distribution of temperature versus NVG depth is bi-modal and displays two distinct thermal populations that are interpreted to represent both the lithosphere-asthenosphere boundary (LAB) and mid-lithosphere discontinuities (MLD). LAB arrivals occur in the western US at 60-85 km and 1200-1400 °C depth suggesting that they manifest partial melt near the base of the thermal plate. MLD arrivals primarily occur at 70-110 km depth and 700-900 °C and we hypothesize that these arrivals are caused by a low-velocity metasomatic layer containing phlogopite resulting from magma crystallization products that accumulate within long-lived thick lithosphere.

Array-Based Receiver Function Analysis of the Subducting Juan de Fuca Plate Beneath the Mount St. Helens Region and its Implications for Subduction Geometry and Metamorphism

Science.gov (United States)

Mann, M. E.; Abers, G. A.; Creager, K. C.; Ulberg, C. W.; Crosbie, K.

2017-12-01

Mount St. Helens (MSH) is unusual as a prolific arc volcano located 50 km towards the forearc of the main Cascade arc. The iMUSH (imaging Magma Under mount St. Helens) broadband deployment featured 70 seismometers at 10-km spacing in a 50-km radius around MSH, spanning a sufficient width for testing along-strike variation in subsurface geometry as well as deep controls on volcanism in the Cascade arc. Previous estimates of the geometry of the subducting Juan de Fuca (JdF) slab are extrapolated to MSH from several hundred km to the north and south. We analyze both P-to-S receiver functions and 2-D Born migrations of the full data set to locate the upper plate Moho and the dip and depth of the subducting slab. The strongest coherent phase off the subducting slab is the primary reverberation (Ppxs; topside P-to-S reflection) from the Moho of the subducting JdF plate, as indicated by its polarity and spatial pattern. Migration images show a dipping low velocity layer at depths less than 50 km that we interpret as the subducting JdF crust. Its disappearance beyond 50 km depth may indicate dehydration of subducting crust or disruption of high fluid pressures along the megathrust. The lower boundary of the low velocity zone, the JdF Moho, persists in the migration image to depths of at least 90 km and is imaged at 74 km beneath MSH, dipping 23 degrees. The slab surface is 68 km beneath MSH and 85 km beneath Mount Adams volcano to the east. The JdF Moho exhibits 10% velocity contrasts as deep as 85 km, an observation difficult to reconcile with simple models of crustal eclogitization. The geometry and thickness of the JdF crust and upper plate Moho is consistent with similar transects of Cascadia and does not vary along strike beneath iMUSH, indicating a continuous slab with no major disruption. The upper plate Moho is clear on the east side of the array but it disappears west of MSH, a feature we interpret as a result of both serpentinization of the mantle wedge and a

Death Valley turtlebacks: Mesozoic contractional structures overprinted by Cenozoic extension and metamorphism beneath syn-extensional plutons

Science.gov (United States)

Pavlis, T. L.; Miller, M.; Serpa, L.

2008-07-01

The term turtleback was first coined to describe the curvilinear fault surfaces that produced a distinctive geomorphic form in the Black Mountains east of Death Valley, and although it was decades before their full significance was appreciated, they remain one of the most distinctive features of the extensional structure of the Death Valley region. Historically the interpretation of the features has varied markedly, and misconceptions about their character continue to abound, including descriptions in popular field guides for the area. It the 1990's, however, the full history of the systems began to be apparent from several key data: 1) the dating of the plutonic assemblage associated with the turtlebacks demonstrated that late Miocene, syn-extensional plutonism was fundamental to their formation; 2) the plutonic assemblage forms an intrusive sheet structurally above the turtlebacks, indicating a tie between much of the high grade metamorphism and Cenozoic plutonism; 3) a modern analog for the syn-extensional plutonism in the Black Mountains was recognized beneath Death Valley with the imaging of a mid-crustal magma body; 4) the Neogene structural history was worked out in the turtlebacks showing that folding of early-formed shear zones formed the turtleback anticlinoria but overprinting by brittle faults produced the final form as they cut obliquely across the older structure; and 5) the pre-extensional structural history was clarified, demonstrating that Mesozoic basement-involved thrust systems are present within the turtlebacks, but have been overprinted by the extensional system. An unresolved issue is the significance of Eocene U-Pb dates for pegmatites within the region, but presumably these relate somehow to the pre-extensional history. Miller and Pavlis (2005; E. Sci. Rev.) reviewed many features of the turtlebacks, and our working model for the region is that the turtlebacks originated as mid-crustal ductile-thrust systems within the Cordilleran fold

Death Valley turtlebacks: Mesozoic contractional structures overprinted by Cenozoic extension and metamorphism beneath syn-extensional plutons

Energy Technology Data Exchange (ETDEWEB)

Pavlis, T L; Serpa, L [Department of Geological Sciences, University of Texas at El Paso, El Paso, TX 7996 (United States); Miller, M [Department of Geological Sciences, University of Oregon, Eugene, OR 97403 (United States)], E-mail: tlpavlis@utep.edu

2008-07-01

The term turtleback was first coined to describe the curvilinear fault surfaces that produced a distinctive geomorphic form in the Black Mountains east of Death Valley, and although it was decades before their full significance was appreciated, they remain one of the most distinctive features of the extensional structure of the Death Valley region. Historically the interpretation of the features has varied markedly, and misconceptions about their character continue to abound, including descriptions in popular field guides for the area. It the 1990's, however, the full history of the systems began to be apparent from several key data: 1) the dating of the plutonic assemblage associated with the turtlebacks demonstrated that late Miocene, syn-extensional plutonism was fundamental to their formation; 2) the plutonic assemblage forms an intrusive sheet structurally above the turtlebacks, indicating a tie between much of the high grade metamorphism and Cenozoic plutonism; 3) a modern analog for the syn-extensional plutonism in the Black Mountains was recognized beneath Death Valley with the imaging of a mid-crustal magma body; 4) the Neogene structural history was worked out in the turtlebacks showing that folding of early-formed shear zones formed the turtleback anticlinoria but overprinting by brittle faults produced the final form as they cut obliquely across the older structure; and 5) the pre-extensional structural history was clarified, demonstrating that Mesozoic basement-involved thrust systems are present within the turtlebacks, but have been overprinted by the extensional system. An unresolved issue is the significance of Eocene U-Pb dates for pegmatites within the region, but presumably these relate somehow to the pre-extensional history. Miller and Pavlis (2005; E. Sci. Rev.) reviewed many features of the turtlebacks, and our working model for the region is that the turtlebacks originated as mid-crustal ductile-thrust systems within the Cordilleran fold

Death Valley turtlebacks: Mesozoic contractional structures overprinted by Cenozoic extension and metamorphism beneath syn-extensional plutons

International Nuclear Information System (INIS)

Pavlis, T L; Serpa, L; Miller, M

2008-01-01

The term turtleback was first coined to describe the curvilinear fault surfaces that produced a distinctive geomorphic form in the Black Mountains east of Death Valley, and although it was decades before their full significance was appreciated, they remain one of the most distinctive features of the extensional structure of the Death Valley region. Historically the interpretation of the features has varied markedly, and misconceptions about their character continue to abound, including descriptions in popular field guides for the area. It the 1990's, however, the full history of the systems began to be apparent from several key data: 1) the dating of the plutonic assemblage associated with the turtlebacks demonstrated that late Miocene, syn-extensional plutonism was fundamental to their formation; 2) the plutonic assemblage forms an intrusive sheet structurally above the turtlebacks, indicating a tie between much of the high grade metamorphism and Cenozoic plutonism; 3) a modern analog for the syn-extensional plutonism in the Black Mountains was recognized beneath Death Valley with the imaging of a mid-crustal magma body; 4) the Neogene structural history was worked out in the turtlebacks showing that folding of early-formed shear zones formed the turtleback anticlinoria but overprinting by brittle faults produced the final form as they cut obliquely across the older structure; and 5) the pre-extensional structural history was clarified, demonstrating that Mesozoic basement-involved thrust systems are present within the turtlebacks, but have been overprinted by the extensional system. An unresolved issue is the significance of Eocene U-Pb dates for pegmatites within the region, but presumably these relate somehow to the pre-extensional history. Miller and Pavlis (2005; E. Sci. Rev.) reviewed many features of the turtlebacks, and our working model for the region is that the turtlebacks originated as mid-crustal ductile-thrust systems within the Cordilleran fold

Regional variations in upper mantle compressional velocities beneath southern California 1. Post-shock temperatures: Their experimental determination, calculation, and implications, 2.. Ph.D. Thesis

Science.gov (United States)

Raikes, S. A.

1978-01-01

The compressional velocity within the upper mantle beneath Southern California is investigated through observations of the dependence of teleseismic P-delays at all stations of the array on the distance and azimuth to the event. The variation of residuals with azimuth was found to be as large as 1.3 sec at a single station; the delays were stable as a function of time, and no evidence was found for temporal velocity variations related to seismic activity in the area. These delays were used in the construction of models for the upper mantle P-velocity structure to depths of 150 km, both by ray tracing and inversion techniques. The models exhibit considerable lateral heterogeneity including a region of low velocity beneath the Imperial Valley, and regions of increased velocity beneath the Sierra Nevada and much of the Transverse Ranges. The development is described of a technique for the experimental determination of post-shock temperatures, and its application to several metals and silicates shocked to pressures in the range 5 to 30 GPa. The technique utilizes an infra-red radiation detector to determine the brightness temperature of the free surface of the sample after the shock wave has passed through it.

What Lies beneath Seemingly Positive Campus Climate Results: Institutional Sexism, Racism, and Male Hostility toward Equity Initiatives and Liberal Bias

Science.gov (United States)

Vaccaro, Annemarie

2010-01-01

This article presents qualitative results from a campus climate study at one predominately white university. Data analysis uncovered "what lies beneath" a seemingly positive campus climate. Gender differences in survey responses suggest that men and women experienced the climate in vastly different ways. Additionally, lack of deep diversity…

Fertile lithospheric mantle beneath the northwestern North China and its implication for the subduction of the Paleo-Asian Ocean

Science.gov (United States)

Dai, H. K.; Zheng, J.; Su, Y. P.; Xiong, Q.; Pan, S. K.

2017-12-01

The nature of the sub-continental lithospheric mantle (SCLM) beneath the western North China Craton (NCC) is poorly known, which hinders understanding the cratonic response to the southward subduction of the Paleo-Asian Ocean. Mineral chemical data of spinel lherzolite xenoliths from newly discovered Cenozoic Langshan basalts in the northwestern part of the craton have been integrated with data from other localities across the western NCC, to put constrains on the SCLM nature and to explore the reworking processes involved. Compositions of mineral cores (i.e., Mg# in olivine = 88 91) and P-T estimates ( 1.2 GPa, 950 oC) suggest the Langshan xenoliths/xenocrysts represent fragments of the uppermost SCLM and experienced ancient continental crust, and 2) the sharp decrease in lithospheric thickness from the inner part to the northern margin of the western NCC, the SCLM beneath the northwestern part should have been strongly rejuvenated or replaced by fertile and non-cratonic mantle. Combined with other geological evidence on the northwestern margin, the mantle replacement and metasomatism were likely triggered by southward subduction of the Paleo-Asian Ocean.

The resilience of postglacial hunter-gatherers to abrupt climate change.

Science.gov (United States)

Blockley, Simon; Candy, Ian; Matthews, Ian; Langdon, Pete; Langdon, Cath; Palmer, Adrian; Lincoln, Paul; Abrook, Ashley; Taylor, Barry; Conneller, Chantal; Bayliss, Alex; MacLeod, Alison; Deeprose, Laura; Darvill, Chris; Kearney, Rebecca; Beavan, Nancy; Staff, Richard; Bamforth, Michael; Taylor, Maisie; Milner, Nicky

2018-05-01

Understanding the resilience of early societies to climate change is an essential part of exploring the environmental sensitivity of human populations. There is significant interest in the role of abrupt climate events as a driver of early Holocene human activity, but there are very few well-dated records directly compared with local climate archives. Here, we present evidence from the internationally important Mesolithic site of Star Carr showing occupation during the early Holocene, which is directly compared with a high-resolution palaeoclimate record from neighbouring lake beds. We show that-once established-there was intensive human activity at the site for several hundred years when the community was subject to multiple, severe, abrupt climate events that impacted air temperatures, the landscape and the ecosystem of the region. However, these results show that occupation and activity at the site persisted regardless of the environmental stresses experienced by this society. The Star Carr population displayed a high level of resilience to climate change, suggesting that postglacial populations were not necessarily held hostage to the flickering switch of climate change. Instead, we show that local, intrinsic changes in the wetland environment were more significant in determining human activity than the large-scale abrupt early Holocene climate events.

Poachers and Poverty: Assessing Objective and Subjective Measures of Poverty among Illegal Hunters Outside Ruaha National Park, Tanzania

Directory of Open Access Journals (Sweden)

Eli J Knapp

2017-01-01

Full Text Available Illegal hunters in Africa may be making rational decisions about the hunting activities they partake in. These decisions could be linked to their socioeconomic status and the livelihood opportunities available to them. In particular, poverty is widely considered the leading driver that causes a household's inhabitants to take up poaching in protected areas. Programs aiming to protect vulnerable wildlife populations by mitigating poaching have historically relied upon income-based poverty metrics in efforts to reduce regional poverty and incentivise local inhabitants to discontinue poaching activities. Because such data sets that deal with poachers directly are rare, assumptions about the role of poverty, and the extent of poverty, that drives poaching have been hard to test. This study uses a unique sample of 173 self-admitted poachers living in villages adjacent to Ruaha National Park in Tanzania to explore the influence of poverty on poaching. Results indicated high demographic and household economy heterogeneity among poaching households. Capability deprivation examined more subjective measures of poverty and revealed that poachers are strongly motivated by the need to improve their incomes, but are not necessarily the poorest of the poor.

ISOLASI DAN IDENTIFIKASI SENYAWA KIMIA SERTA UJI AKTIVITAS ANTICANDIDAISIS SERBUK DAUN SIRIH DUDUK (Piper sarmentosum Roxb. Ex Hunter

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Suwandri

2006-11-01

Full Text Available Sirih duduk or Piper sarmentosum Roxb. ex Hunter have been long used the people in Indonesia for traditional medicine to cure various diseases. One of them was used to treat fungoid diseases. This research was aimed to examine the anticandidaisis activity from extract of P. sarmentosum leaves and to isolate and identify the anticandidaisis compounds from P. sarmentosum leaves. The isolation bioactive compounds of P. sarmentosum leaves was performed by extraction the powder of P. sarmentosum leaves using methanol and the bioactivity tests were performed against Candida albicans. The methanol extracts was then fractionated using organic solvents such as n-hexane, benzene, chloroform, and ethyl acetate. Identification of the bioactive compounds was carried out using ultraviolet-visible spectrometry, fourier transform infra red spectrometry and gas chromatography-mass spectrometry. The result showed that the chloroform fraction of methanol extract of P. sarmentosum leaves have activity against C. albicans. The fractionation was performed by coloumn chromatography using n-hexane-ethyl acetate(1:1 eluent. A bioactive compound of sinamic acid derivative was 4-ethoxy-2-hidroxy-3,5-dimethoxy sinamic acid could be purely isolated.

Interaction of the Cyprus/Tethys Slab With the Mantle Transition Zone Beneath Anatolia

Science.gov (United States)

Thompson, D. A.; Rost, S.; Taylor, G.; Cornwell, D. G.

2017-12-01

The geodynamics of the eastern Mediterranean are dominated by northward motion of the Arabian/African continents and subduction of the oldest oceanic crust on the planet along the Aegean and Cyprean trenches. These slabs have previously been imaged using seismic tomography on a continental scale, but detailed information regarding their descent from upper to lower mantle and how they interact with the mantle transition zone have been severely lacking. The Dense Array for North Anatolia (DANA) was a 73 station passive seismic deployment active between 2012-2013 with the primary aim of imaging shallow structure beneath the North Anatolian Fault. However, we exploit the exceptional dataset recorded by DANA to characterise a region where the Cyprus Slab impinges upon the mantle transition zone beneath northern Turkey, providing arguably the most detailed view of a slab as it transits from the upper to lower mantle. We map varying depths and amplitudes of the transition zone seismic discontinuities (`410', `520' and `660') in 3D using over 1500 high quality receiver functions over an area of approximately 200km x 300km. The `410' is observed close to its predicted depth, but the `660' is depressed to >670 km across the entirety of the study region. This is consistent with an accumulation of cold subducted material at the base of the upper mantle, and the presence of a `520' discontinuity in the vicinity of the slab surface also suggests that the slab is present deep within the transition zone. Anomalous low velocity layers above and within the transition zone are constrained and may indicate hydration and ongoing mass/fluid flux between upper and lower mantle in the presence of subduction. The results of the study have implications not only for the regional geodynamics of Anatolia, but also for slab dynamics globally.

Loading of the San Andreas fault by flood-induced rupture of faults beneath the Salton Sea

Science.gov (United States)

Brothers, Daniel; Kilb, Debi; Luttrell, Karen; Driscoll, Neal W.; Kent, Graham

2011-01-01

The southern San Andreas fault has not experienced a large earthquake for approximately 300 years, yet the previous five earthquakes occurred at ~180-year intervals. Large strike-slip faults are often segmented by lateral stepover zones. Movement on smaller faults within a stepover zone could perturb the main fault segments and potentially trigger a large earthquake. The southern San Andreas fault terminates in an extensional stepover zone beneath the Salton Sea—a lake that has experienced periodic flooding and desiccation since the late Holocene. Here we reconstruct the magnitude and timing of fault activity beneath the Salton Sea over several earthquake cycles. We observe coincident timing between flooding events, stepover fault displacement and ruptures on the San Andreas fault. Using Coulomb stress models, we show that the combined effect of lake loading, stepover fault movement and increased pore pressure could increase stress on the southern San Andreas fault to levels sufficient to induce failure. We conclude that rupture of the stepover faults, caused by periodic flooding of the palaeo-Salton Sea and by tectonic forcing, had the potential to trigger earthquake rupture on the southern San Andreas fault. Extensional stepover zones are highly susceptible to rapid stress loading and thus the Salton Sea may be a nucleation point for large ruptures on the southern San Andreas fault.

Local Upper Mantle Upwelling beneath New England: Evidence from Seismic Anisotropy.

Science.gov (United States)

Levin, V. L.; Long, M. D.; Lopez, I.; Li, Y.; Skryzalin, P. A.

2017-12-01

The upper mantle beneath eastern North America contains regions where seismic wave speed is significantly reduced. As they cut across the trend of the Appalachian terranes, these anomalies likely post-date the Paleozoic assembly of Pangea. Most prominent of them, the North Appalachian Anomaly (NAA), has been alternatively explained by the localized disruption of lithospheric fabric, the passage of the Great Meteor Hot Spot, and the current local upwelling of the asthenosphere. Comprehensive mapping of shear wave splitting identified a local perturbation of an otherwise uniform regional pattern, with no apparent splitting occurring at a site within the NAA. To evaluate the reality of this apparent localized disruption in the anisotropic fabric of the upper mantle beneath northeastern North America we used observations of shear wave splitting from a set of long-running observatories not included in previous studies. Three methods of evaluating shear wave splitting (rotation-correlation, minimization of the transverse component, and the splitting intensity) yield complementary results. We show that splitting of core-refracted shear waves within the outline of the NAA is significantly weaker than towards its edges and beyond them (Figure 1). Average fast orientations are close to the absolute plate motion in the hot-spot reference frame, thus we can attribute a large fraction of this signal to the coherently sheared sub-lithospheric upper mantle. A decrease in average delay we observe, from 1 s outside the NAA to under 0.2 s within it, translates into a reduction of the vertical extent of the sheared layer from 130 km to 16 km (assuming 4% anisotropy), or alternatively into a weakening of the azimuthal anisotropy from 5% to 0.6% (assuming a 100 km thick layer). The splitting reduction within the NAA is consistent with a localized change in anisotropic fabric that would be expected in case of geologically recent sub-vertical flow overprinting the broadly uniform upper

Making a Home in the Taiga: Movements, Paths and Signs among Orochen-Evenki Hunters and Herders of Zabaikal Krai (South East Siberia

Directory of Open Access Journals (Sweden)

Donatas Brandišauskas

2012-06-01

Full Text Available In this article, I will explore interrelations between place making, movement, use of paths and signs among the Orochen of Zabaikal Krai (Province. Although under the Russian Tsars Orochen-Evenki hunters and herders were referred to negatively as wanderers; today my ethnography demonstrates how movements of animals and humans are crucial for the success of their subsistence, place making and worldview. Hence, walking in the taiga is an important skill that is essential to hunting and herding activities when humans strive to identify animals' 'living places' (Orochen bikit by reading their tracks and movements. Humans also leave their own tracks and paths as well as signs communicating with each other while subsisting in remote areas, in this way creating their own living places. Thereby, I show how movements and the use of paths is an important dimension of Orochen-Evenki wellbeing as well as their moral code.

Numerical simulation of wave-induced scour and backfilling processes beneath submarine pipelines

DEFF Research Database (Denmark)

Fuhrman, David R.; Baykal, Cüneyt; Sumer, B. Mutlu

2014-01-01

A fully-coupled hydrodynamic/morphodynamic numerical model is presented and utilized for the simulation of wave-induced scour and backfilling processes beneath submarine pipelines. The model is based on solutions to Reynolds-averaged Navier–Stokes equations, coupled with k−ω turbulence closure......≤30 demonstrate reasonable match with previous experiments, both in terms of the equilibrium scour depth as well as the scour time scale. Wave-induced backfilling processes are additionally studied by subjecting initial conditions taken from scour simulations with larger KC to new wave climates...... characterized by lower KC values. The simulations considered demonstrate the ability of the model to predict backfilling toward expected equilibrium scour depths based on the new wave climate, in line with experimental expectations. The simulated backfilling process is characterized by two stages: (1...

Preliminary results of characteristic seismic anisotropy beneath Sunda-Banda subduction-collision zone

Energy Technology Data Exchange (ETDEWEB)

Wiyono, Samsul H., E-mail: samsul.wiyono@bmkg.go.id [Study Program of Earth Sciences, Faculty of Earth Sciences and Technology, Institute of Technology Bandung, Bandung 40132 (Indonesia); Indonesia’s Agency for Meteorology Climatology and Geophysics, Jakarta 10610 (Indonesia); Nugraha, Andri Dian, E-mail: nugraha@gf.itb.ac.id [Indonesia’s Agency for Meteorology Climatology and Geophysics, Jakarta 10610 (Indonesia); Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Bandung 40132, Indonesia, Phone: +62-22 2534137 (Indonesia)

2015-04-24

Determining of seismic anisotropy allowed us for understanding the deformation processes that occured in the past and present. In this study, we performed shear wave splitting to characterize seismic anisotropy beneath Sunda-Banda subduction-collision zone. For about 1,610 XKS waveforms from INATEWS-BMKG networks have been analyzed. From its measurements showed that fast polarization direction is consistent with trench-perpendicular orientation but several stations presented different orientation. We also compared between fast polarization direction with absolute plate motion in the no net rotation and hotspot frame. Its result showed that both absolute plate motion frame had strong correlation with fast polarization direction. Strong correlation between the fast polarization direction and the absolute plate motion can be interpreted as the possibility of dominant anisotropy is in the asthenosphere.

Drought-induced recharge promotes long-term storage of porewater salinity beneath a prairie wetland

Science.gov (United States)

Levy, Zeno F.; Rosenberry, Donald O.; Moucha, Robert; Mushet, David M.; Goldhaber, Martin B.; LaBaugh, James W.; Fiorentino, Anthony J.; Siegel, Donald I.

2018-02-01

Subsurface storage of sulfate salts allows closed-basin wetlands in the semiarid Prairie Pothole Region (PPR) of North America to maintain moderate surface water salinity (total dissolved solids [TDS] from 1 to 10 g L-1), which provides critical habitat for communities of aquatic biota. However, it is unclear how the salinity of wetland ponds will respond to a recent shift in mid-continental climate to wetter conditions. To understand better the mechanisms that control surface-subsurface salinity exchanges during regional dry-wet climate cycles, we made a detailed geoelectrical study of a closed-basin prairie wetland (P1 in the Cottonwood Lake Study Area, North Dakota) that is currently experiencing record wet conditions. We found saline lenses of sulfate-rich porewater (TDS > 10 g L-1) contained in fine-grained wetland sediments 2-4 m beneath the bathymetric low of the wetland and within the currently ponded area along the shoreline of a prior pond stand (c. 1983). During the most recent drought (1988-1993), the wetland switched from a groundwater discharge to recharge function, allowing salts dissolved in surface runoff to move into wetland sediments beneath the bathymetric low of the basin. However, groundwater levels during this time did not decline to the elevation of the saline lenses, suggesting these features formed during more extended paleo-droughts and are stable in the subsurface on at least centennial timescales. We hypothesize a "drought-induced recharge" mechanism that allows wetland ponds to maintain moderate salinity under semiarid climate. Discharge of drought-derived saline groundwater has the potential to increase the salinity of wetland ponds during wet climate.

Mantle transition zone structure beneath the Canadian Shield

Science.gov (United States)

Thompson, D. A.; Helffrich, G. R.; Bastow, I. D.; Kendall, J. M.; Wookey, J.; Eaton, D. W.; Snyder, D. B.

2010-12-01

The Canadian Shield is underlain by one of the deepest and most laterally extensive continental roots on the planet. Seismological constraints on the mantle structure beneath the region are presently lacking due to the paucity of stations in this remote area. Presented here is a receiver function study on transition zone structure using data from recently deployed seismic networks from the Hudson Bay region. High resolution images based on high signal-to-noise ratio data show clear arrivals from the 410 km and 660 km discontinuities, revealing remarkably little variation in transition zone structure. Transition zone thickness is close to the global average (averaging 245 km across the study area), and any deviations in Pds arrival time from reference Earth models can be readily explained by upper-mantle velocity structure. The 520 km discontinuity is not a ubiquitous feature, and is only weakly observed in localised areas. These results imply that the Laurentian root is likely confined to the upper-mantle and if any mantle downwelling exists, possibly explaining the existence of Hudson Bay, it is also confined to the upper 400 km. Any thermal perturbations at transition zone depths associated with the existence of the root, whether they be cold downwellings or elevated temperatures due to the insulating effect of the root, are thus either non-existent or below the resolution of the study.

Planet hunters. VI. An independent characterization of KOI-351 and several long period planet candidates from the Kepler archival data

International Nuclear Information System (INIS)

Schmitt, Joseph R.; Wang, Ji; Fischer, Debra A.; Moriarty, John C.; Boyajian, Tabetha S.; Jek, Kian J.; LaCourse, Daryll; Omohundro, Mark R.; Winarski, Troy; Goodman, Samuel Jon; Jebson, Tony; Schwengeler, Hans Martin; Paterson, David A.; Schwamb, Megan E.; Lintott, Chris; Simpson, Robert; Lynn, Stuart; Smith, Arfon M.; Parrish, Michael; Schawinski, Kevin

2014-01-01

We report the discovery of 14 new transiting planet candidates in the Kepler field from the Planet Hunters citizen science program. None of these candidates overlapped with Kepler Objects of Interest (KOIs) at the time of submission. We report the discovery of one more addition to the six planet candidate system around KOI-351, making it the only seven planet candidate system from Kepler. Additionally, KOI-351 bears some resemblance to our own solar system, with the inner five planets ranging from Earth to mini-Neptune radii and the outer planets being gas giants; however, this system is very compact, with all seven planet candidates orbiting ≲ 1 AU from their host star. A Hill stability test and an orbital integration of the system shows that the system is stable. Furthermore, we significantly add to the population of long period transiting planets; periods range from 124 to 904 days, eight of them more than one Earth year long. Seven of these 14 candidates reside in their host star's habitable zone.

Peeking Beneath the Caldera: Communicating Subsurface Knowledge of Newberry Volcano

Science.gov (United States)

Mark-Moser, M.; Rose, K.; Schultz, J.; Cameron, E.

2016-12-01

"Imaging the Subsurface: Enhanced Geothermal Systems and Exploring Beneath Newberry Volcano" is an interactive website that presents a three-dimensional subsurface model of Newberry Volcano developed at National Energy Technology Laboratory (NETL). Created using the Story Maps application by ArcGIS Online, this format's dynamic capabilities provide the user the opportunity for multimedia engagement with the datasets and information used to build the subsurface model. This website allows for an interactive experience that the user dictates, including interactive maps, instructive videos and video capture of the subsurface model, and linked information throughout the text. This Story Map offers a general background on the technology of enhanced geothermal systems and the geologic and development history of Newberry Volcano before presenting NETL's modeling efforts that support the installation of enhanced geothermal systems. The model is driven by multiple geologic and geophysical datasets to compare and contrast results which allow for the targeting of potential EGS sites and the reduction of subsurface uncertainty. This Story Map aims to communicate to a broad audience, and provides a platform to effectively introduce the model to researchers and stakeholders.

Silt and gas accumulation beneath an artificial recharge spreading basin, Southwestern Utah, U.S.A.

Science.gov (United States)

Heilweil, V.M.; Solomon, D.K.; Ortiz, G.

2009-01-01

Sand Hollow Reservoir in southwestern Utah, USA, is operated for both surface-water storage and artificial recharge to the underlying Navajo Sandstone. The total volume of estimated artificial recharge between 2002 and 2007 is 85 million cubic meters (69,000 acre-feet). Since 2002, artificial recharge rates have generally been declining and are inversely correlated with the increasing surface area of the reservoir. Permeability testing of core samples retrieved from beneath the reservoir indicates that this decline may not be due to silt accumulation. Artificial recharge rates also show much seasonal variability. Calculations of apparent intrinsic permeability show that these variations can only partly be explained by variation in water viscosity associated with seasonal changes in water temperature. Sporadic seasonal trends in recharge rates and intrinsic permeability during 2002-2004 could be associated with the large fluctuations in reservoir elevation and wetted area. From 2005 through 2007, the reservoir was mostly full and there has been a more consistent seasonal pattern of minimum recharge rates during the summer and maximum rates during the autumn. Total dissolved-gas pressure measurements indicate the presence of biogenic gas bubbles in the shallow sediments beneath the shallower parts of Sand Hollow Reservoir when the water is warmer. Permeability reduction associated with this gas clogging may contribute to the decrease in artificial recharge rates during the spring and summer, with a subsequently increasing recharge rates in the autumn associated with a decline in volume of gas bubbles. Other possible causes for seasonal variation in artificial recharge rates require further investigation.

Shallow crustal radial anisotropy beneath the Tehran basin of Iran from seismic ambient noise tomography

Science.gov (United States)

Shirzad, Taghi; Shomali, Z. Hossein

2014-06-01

We studied the shear wave velocity structure and radial anisotropy beneath the Tehran basin by analyzing the Rayleigh wave and Love wave empirical Green's functions obtained from cross-correlation of seismic ambient noise. Approximately 199 inter-station Rayleigh and Love wave empirical Green's functions with sufficient signal-to-noise ratios extracted from 30 stations with various sensor types were used for phase velocity dispersion analysis of periods ranging from 1 to 7 s using an image transformation analysis technique. Dispersion curves extracted from the phase velocity maps were inverted based on non-linear damped least squares inversion method to obtain a quasi-3D model of crustal shear wave velocities. The data used in this study provide an unprecedented opportunity to resolve the spatial distribution of radial anisotropy within the uppermost crust beneath the Tehran basin. The quasi-3D shear wave velocity model obtained in this analysis delineates several distinct low- and high-velocity zones that are generally separated by geological boundaries. High-shear-velocity zones are located primarily around the mountain ranges and extend to depths of 2.0 km, while the low-shear-velocity zone is located near regions with sedimentary layers. In the shallow subsurface, our results indicate strong radial anisotropy with negative magnitude (VSV > VSH) primarily associated with thick sedimentary deposits, reflecting vertical alignment of cracks. With increasing depth, the magnitude of the radial anisotropy shifts from predominantly negative (less than -10%) to predominantly positive (greater than 5%). Our results show a distinct change in radial anisotropy between the uppermost sedimentary layer and the bedrock.

Crustal Thickness Beneath Libya and the Origin of Partial Melt Beneath AS Sawda Volcanic Province From Receiver Function Constraints

Science.gov (United States)

Lemnifi, Awad A.; Elshaafi, Abdelsalam; Browning, John; Aouad, Nassib S.; El Ebaidi, Saad K.; Liu, Kelly K.; Gudmundsson, Agust

2017-12-01

This study investigates crustal thickness and properties within the Libyan region. Results obtained from 15 seismic stations belonging to the Libyan Center for Remote Sensing and Space Science are reported, in addition to 3 seismic stations publically available, using receiver functions. The results show crustal thicknesses ranging from 24 km to 36 km (with uncertainties ranging between ±0.10 km and ±0.90 km). More specifically, crustal thickness ranges from 32 km to 36 km in the southern portion of the Libyan territory then becomes thinner, between 24 km and 30 km, in the coastal areas of Libya and thinnest, between 24 km and 28 km, in the Sirt Basin. The observed high Vp/Vs value of 1.91 at one station located at the AS Sawda Volcanic Province in central Libya indicates the presence of either partial melt or an abnormally warm area. This finding suggests that magma reservoirs beneath the Libyan territory may still be partially molten and active, thereby posing significant earthquake and volcanic risks. The hypothesis of an active magma source is further demonstrated though the presence of asthenospheric upwelling and extension of the Sirt Basin. This study provides a new calculation of unconsolidated sediment layers by using the arrival time of the P to S converted phases. The results show sediments thicknesses of 0.4 km to 3.7 km, with the Vp/Vs values ranging from 2.2 to 4.8. The variations in crustal thickness throughout the region are correlated with surface elevation and Bouguer gravity anomalies, which suggest that they are isostatically compensated.

The Impacts of Soil Fertility and Salinity on Soil Nitrogen Dynamics Mediated by the Soil Microbial Community Beneath the Halophytic Shrub Tamarisk.

Science.gov (United States)

Iwaoka, Chikae; Imada, Shogo; Taniguchi, Takeshi; Du, Sheng; Yamanaka, Norikazu; Tateno, Ryunosuke

2018-05-01

Nitrogen (N) is one of the most common limiting nutrients for primary production in terrestrial ecosystems. Soil microbes transform organic N into inorganic N, which is available to plants, but soil microbe activity in drylands is sometimes critically suppressed by environmental factors, such as low soil substrate availability or high salinity. Tamarisk (Tamarix spp.) is a halophytic shrub species that is widely distributed in the drylands of China; it produces litter enriched in nutrients and salts that are thought to increase soil fertility and salinity under its crown. To elucidate the effects of tamarisks on the soil microbial community, and thus N dynamics, by creating "islands of fertility" and "islands of salinity," we collected soil samples from under tamarisk crowns and adjacent barren areas at three habitats in the summer and fall. We analyzed soil physicochemical properties, inorganic N dynamics, and prokaryotic community abundance and composition. In soils sampled beneath tamarisks, the N mineralization rate was significantly higher, and the prokaryotic community structure was significantly different, from soils sampled in barren areas, irrespective of site and season. Tamarisks provided suitable nutrient conditions for one of the important decomposers in the area, Verrucomicrobia, by creating "islands of fertility," but provided unsuitable salinity conditions for other important decomposers, Flavobacteria, Gammaproteobacteria, and Deltaproteobacteria, by mitigating salt accumulation. However, the quantity of these decomposers tended to be higher beneath tamarisks, because they were relatively unaffected by the small salinity gradient created by the tamarisks, which may explain the higher N mineralization rate beneath tamarisks.

S-wave triggering of tremor beneath the Parkfield, California, section of the San Andreas fault by the 2011 Tohoku, Japan earthquake: observations and theory

Science.gov (United States)

Hill, David P.; Peng, Zhigang; Shelly, David R.; Aiken, Chastity

2013-01-01

The dynamic stresses that are associated with the energetic seismic waves generated by the Mw 9.0 Tohoku earthquake off the northeast coast of Japan triggered bursts of tectonic tremor beneath the Parkfield section of the San Andreas fault (SAF) at an epicentral distance of ∼8200  km. The onset of tremor begins midway through the ∼100‐s‐period S‐wave arrival, with a minor burst coinciding with the SHSH arrival, as recorded on the nearby broadband seismic station PKD. A more pronounced burst coincides with the Love arrival, followed by a series of impulsive tremor bursts apparently modulated by the 20‐ to 30‐s‐period Rayleigh wave. The triggered tremor was located at depths between 20 and 30 km beneath the surface trace of the fault, with the burst coincident with the S wave centered beneath the fault 30 km northwest of Parkfield. Most of the subsequent activity, including the tremor coincident with the SHSH arrival, was concentrated beneath a stretch of the fault extending from 10 to 40 km southeast of Parkfield. The seismic waves from the Tohoku epicenter form a horizontal incidence angle of ∼14°, with respect to the local strike of the SAF. Computed peak dynamic Coulomb stresses on the fault at tremor depths are in the 0.7–10 kPa range. The apparent modulation of tremor bursts by the small, strike‐parallel Rayleigh‐wave stresses (∼0.7  kPa) is likely enabled by pore pressure variations driven by the Rayleigh‐wave dilatational stress. These results are consistent with the strike‐parallel dynamic stresses (δτs) associated with the S, SHSH, and surface‐wave phases triggering small increments of dextral slip on the fault with a low friction (μ∼0.2). The vertical dynamic stresses δτd do not trigger tremor with vertical or oblique slip under this simple Coulomb failure model.

Heterogeneous distribution of water in the mantle transition zone beneath United States inferred from seismic observations

Science.gov (United States)

Wang, Y.; Pavlis, G. L.; Li, M.

2017-12-01

The amount of water in the Earth's deep mantle is critical for the evolution of the solid Earth and the atmosphere. Mineral physics studies have revealed that Wadsleyite and Ringwoodite in the mantle transition zone could store several times the volume of water in the ocean. However, the water content and its distribution in the transition zone remain enigmatic due to lack of direct observations. Here we use seismic data from the full deployment of the Earthscope Transportable Array to produce 3D image of P to S scattering of the mantle transition zone beneath the United States. We compute the image volume from 141,080 pairs of high quality receiver functions defined by the Earthscope Automated Receiver Survey, reprocessed by the generalized iterative deconvolution method and imaged by the plane wave migration method. We find that the transition zone is filled with previously unrecognized small-scale heterogeneities that produce pervasive, negative polarity P to S conversions. Seismic synthetic modeling using a point source simulation method suggests two possible structures for these objects: 1) a set of randomly distributed blobs of slight difference in size, and 2) near vertical diapir structures from small scale convections. Combining with geodynamic simulations, we interpret the observation as compositional heterogeneity from small-scale, low-velocity bodies that are water enriched. Our results indicate there is a heterogeneous distribution of water through the entire mantle transition zone beneath the contiguous United States.

Evidence for magmatic underplating and partial melt beneath the Canary Islands derived using teleseismic receiver functions

Science.gov (United States)

Lodge, A.; Nippress, S. E. J.; Rietbrock, A.; García-Yeguas, A.; Ibáñez, J. M.

2012-12-01

In recent years, an increasing number of studies have focussed on resolving the internal structure of ocean island volcanoes. Traditionally, active source seismic experiments have been used to image the volcano edifice. Here we present results using the analysis of compressional to shear (P to S) converted seismic phases from teleseismic events, recorded by stations involved in an active source experiment "TOM-TEIDEVS" (Ibáñez et al., 2008), on the island of Tenerife, Canary Islands. We supplement this data with receiver function (RF) analysis of seismograms from the Canary Islands of Lanzarote and La Palma, applying the extended-time multitaper frequency domain cross-correlation estimation method (Helffrich, 2006). We use the neighbourhood inversion approach of Sambridge (1999a,b) to model the RFs and our results indicate magmatic underplating exists beneath all three islands, ranging from 2 to 8 km, but showing no clear correlation with the age of the island. Beneath both La Palma and Tenerife, we find localized low velocity zones (LVZs), which we interpret as due to partial melt, supported by their correlation with the location of historical earthquakes (La Palma) and recent earthquakes (Tenerife). For Lanzarote, we do not sample the most recently volcanically active region and find no evidence for a LVZ. Instead, we find a simple gradational velocity structure, with discontinuities at ˜4, 10 and 18 km depth, in line with previous studies.

Explicit versus implicit motivations: Clarifying how experiences affect turkey hunter satisfaction using revised importance-performance, importance grid, and penalty-reward-contrast analyses

Science.gov (United States)

Schroeder, Susan A.; Cornicelli, Louis; Fulton, David C.; Merchant, Steven S.

2018-01-01

Although research has advanced methods for clarifying factors that relate to customer satisfaction, they have not been embraced by leisure researchers. Using results from a survey of wild turkey hunters, we applied traditional and revised importance-performance (IPA/RIPA), importance-grid analysis (IGA), and penalty-reward-contrast analysis (PRCA) to examine how activity-specific factors influenced satisfaction. Results suggested differences between the explicit and implicit importance of factors related to turkey hunting. Opportunities to kill turkeys were explicitly rated as less important than seeing, hearing, or calling in turkeys, but opportunities for harvest had relatively higher levels of implicit importance. PRCA identified “calling turkeys in” and “hearing gobbling” as minimum requirements that cause dissatisfaction if not fulfilled, but do not provide satisfaction, whereas “seeing turkeys” and an “opportunity to kill a turkey” related to both satisfaction and dissatisfaction. RIPA, IGA, and PRCA could provide valuable insights about factors that may improve satisfaction for leisure participants.

Earliest evidence for equid bit wear in the ancient Near East: The "ass" from Early Bronze Age Tell eṣ-Ṣâfi/Gath, Israel.

Science.gov (United States)

Greenfield, Haskel J; Shai, Itzhaq; Greenfield, Tina L; Arnold, Elizabeth R; Brown, Annie; Eliyahu, Adi; Maeir, Aren M

2018-01-01

Analysis of a sacrificed and interred domestic donkey from an Early Bronze Age (EB) IIIB (c. 2800-2600 BCE) domestic residential neighborhood at Tell eṣ-Ṣâfi/Gath, Israel, indicate the presence of bit wear on the Lower Premolar 2 (LPM2). This is the earliest evidence for the use of a bit among early domestic equids, and in particular donkeys, in the Near East. The mesial enamel surfaces on both the right and left LPM2 of the particular donkey in question are slightly worn in a fashion that suggests that a dental bit (metal, bone, wood, etc.) was used to control the animal. Given the secure chronological context of the burial (beneath the floor of an EB IIIB house), it is suggested that this animal provides the earliest evidence for the use of a bit on an early domestic equid from the Near East.

Seismic Discontinuities within the Crust and Mantle Beneath Indonesia as Inferred from P Receiver Functions

Science.gov (United States)

Woelbern, I.; Rumpker, G.

2015-12-01

Indonesia is situated at the southern margin of SE Asia, which comprises an assemblage of Gondwana-derived continental terranes, suture zones and volcanic arcs. The formation of SE Asia is believed to have started in Early Devonian. Its complex history involves the opening and closure of three distinct Tethys oceans, each accompanied by the rifting of continental fragments. We apply the receiver function technique to data of the temporary MERAMEX network operated in Central Java from May to October 2004 by the GeoForschungsZentrum Potsdam. The network consisted of 112 mobile stations with a spacing of about 10 km covering the full width of the island between the southern and northern coast lines. The tectonic history is reflected in a complex crustal structure of Central Java exhibiting strong topography of the Moho discontinuity related to different tectonic units. A discontinuity of negative impedance contrast is observed throughout the mid-crust interpreted as the top of a low-velocity layer which shows no depth correlation with the Moho interface. Converted phases generated at greater depth beneath Indonesia indicate the existence of multiple seismic discontinuities within the upper mantle and even below. The strongest signal originates from the base of the mantle transition zone, i.e. the 660 km discontinuity. The phase related to the 410 km discontinuity is less pronounced, but clearly identifiable as well. The derived thickness of the mantle-transition zone is in good agreement with the IASP91 velocity model. Additional phases are observed at roughly 33 s and 90 s relative to the P onset, corresponding to about 300 km and 920 km, respectively. A signal of reversed polarity indicates the top of a low velocity layer at about 370 km depth overlying the mantle transition zone.

Results of the radiological survey at 110 E Hunter Avenue, Maywood, New Jersey (MJ022)

International Nuclear Information System (INIS)

Foley, R.D.; Carrier, R.F.; Floyd, L.M.; Crutcher, J.W.

1989-09-01

Maywood Chemical Works (MCW) of Maywood, New Jersey, generated process wastes and residues associated with the production and refining of thorium and thorium compounds from monazite ores from 1916 to 1956. MCW supplied rare earth metals and thorium compounds to the Atomic Energy Commission and various other government agencies from the late 1940s to the mid-1950s. Area residents used the sandlike waste from this thorium extraction process mixed with tea and cocoa leaves as mulch in their yards. Some of these contaminated wastes also eroded from the site into Lodi Brook. At the request of the US Department of Energy (DOE), a group from Oak Ridge National Laboratory conducts investigative radiological surveys of properties in the vicinity of MCW to determine whether a property is contaminated with radioactive residues, principally 232 Th, derived from the MCW site. The survey typically includes direct measurement of gamma radiation levels and soil sampling for radionuclide analyses. The survey of this site, 110 E. Hunter Avenue, Maywood, New Jersey (MJ022), was conducted during 1987. Following the removal of a small chunk of material showing elevated gamma exposure rates, all radionuclide concentrations and measurements conformed to DOE remedial action criteria. The slightly elevated radionuclide concentrations found in other soil samples were the result of naturally enhances radioactivity characteristic of some environmental materials such as coal ash and were unrelated to operations at the MCW site. The survey data demonstrate that the property requires no further action on the part of DOE. 4 refs., 2 figs., 3 tabs

A Biocultural Investigation of Gender Differences in Tobacco Use in an Egalitarian Hunter-Gatherer Population.

Science.gov (United States)

Roulette, Casey J; Hagen, Edward; Hewlett, Barry S

2016-06-01

In the developing world, the dramatic male bias in tobacco use is usually ascribed to pronounced gender disparities in social, political, or economic power. This bias might also reflect under-reporting by woman and/or over-reporting by men. To test the role of gender inequality on gender differences in tobacco use we investigated tobacco use among the Aka, a Congo Basin foraging population noted for its exceptionally high degree of gender equality. We also tested a sexual selection hypothesis-that Aka men's tobacco use is related to risk taking. Tobacco use, income, tobacco purchases, tobacco sharing, reasons for using tobacco, risk taking, and other variables were measured using structured surveys and peer reports. Tobacco use was verified by testing for salivary cotinine, a nicotine metabolite. Contrary to expectations, we found a very large male bias in tobacco use. Low levels of use among females appeared to be explained by aversions to tobacco, concerns over its negative effects on fetal health, and a desire to attract husbands, who prefer nonsmoking wives. High male use appeared to be related to a desire to enhance hunting abilities and attract and/or retain wives, who prefer husbands that smoke. We conclude that low levels of smoking by Aka women are better explained by the hypothesis that women evolved to avoid plant toxins to protect their fetuses and nursing infants. High male use might be better explained by sexual selection. We also highlight the important role that recreational drugs appear to play in hunter-gatherer sharing relationships.

Constraints on seismic anisotropy beneath the Appalachian Mountains from Love-to-Rayleigh wave scattering

Science.gov (United States)

Servali, A.; Long, M. D.; Benoit, M.

2017-12-01

The eastern margin of North America has been affected by a series of mountain building and rifting events that have likely shaped the deep structure of the lithosphere. Observations of seismic anisotropy can provide insight into lithospheric deformation associated with these past tectonic events, as well as into present-day patterns of mantle flow beneath the passive margin. Previous work on SKS splitting beneath eastern North America has revealed fast splitting directions parallel to the strike of the Appalachian orogen in the central and southern Appalachians. A major challenge to the interpretation of SKS splitting measurements, however, is the lack of vertical resolution; isolating anisotropic structures at different depths is therefore difficult. Complementary constraints on the depth distribution of anisotropy can be provided by surface waves. In this study, we analyze the scattering of Love wave energy to Rayleigh waves, which is generated via sharp lateral gradients in anisotropic structure along the ray path. The scattered phases, known as quasi-Love (QL) waves, exhibit amplitude behavior that depend on the strength of the anisotropic contrast as well as the angle between the propagation azimuth and the anisotropic symmetry axis. We analyze data collected by the dense MAGIC seismic array across the central Appalachians. We examine teleseismic earthquakes of magnitude 6.7 and greater over a range of backazimuths, and isolate surface waves at periods between 100 and 500 seconds. We compare the data to synthetic seismograms generated by the Princeton Global ShakeMovie initiative to identify anomalous QL arrivals. We find evidence significant QL arrivals at MAGIC stations, with amplitudes depending on propagation azimuth and station location. Preliminary results are consistent with a sharp lateral gradient in seismic anisotropy across the Appalachian Mountains in the depth range between 100-200 km.

Molar macrowear reveals Neanderthal eco-geographic dietary variation.

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Luca Fiorenza

Full Text Available Neanderthal diets are reported to be based mainly on the consumption of large and medium sized herbivores, while the exploitation of other food types including plants has also been demonstrated. Though some studies conclude that early Homo sapiens were active hunters, the analyses of faunal assemblages, stone tool technologies and stable isotopic studies indicate that they exploited broader dietary resources than Neanderthals. Whereas previous studies assume taxon-specific dietary specializations, we suggest here that the diet of both Neanderthals and early Homo sapiens is determined by ecological conditions. We analyzed molar wear patterns using occlusal fingerprint analysis derived from optical 3D topometry. Molar macrowear accumulates during the lifespan of an individual and thus reflects diet over long periods. Neanderthal and early Homo sapiens maxillary molar macrowear indicates strong eco-geographic dietary variation independent of taxonomic affinities. Based on comparisons with modern hunter-gatherer populations with known diets, Neanderthals as well as early Homo sapiens show high dietary variability in Mediterranean evergreen habitats but a more restricted diet in upper latitude steppe/coniferous forest environments, suggesting a significant consumption of high protein meat resources.

Structure of the Crust beneath Cameroon, West Africa, from the Joint Inversion of Rayleigh Wave Group Velocities and Receiver Functions

Energy Technology Data Exchange (ETDEWEB)

Tokam, A K; Tabod, C T; Nyblade, A A; Julia, J; Wiens, D A; Pasyanos, M E

2010-02-18

The Cameroon Volcanic Line (CVL) is a major geologic feature that cuts across Cameroon from the south west to the north east. It is a unique volcanic lineament which has both an oceanic and a continental sector and consists of a chain of Tertiary to Recent, generally alkaline volcanoes stretching from the Atlantic island of Pagalu to the interior of the African continent. The oceanic sector includes the islands of Bioko (formerly Fernando Po) and Sao Tome and Principe while the continental sector includes the Etinde, Cameroon, Manengouba, Bamboutos, Oku and Mandara mountains, as well as the Adamawa and Biu Plateaus. In addition to the CVL, three other major tectonic features characterize the region: the Benue Trough located northwest of the CVL, the Central African Shear Zone (CASZ), trending N70 degrees E, roughly parallel to the CVL, and the Congo Craton in southern Cameroon. The origin of the CVL is still the subject of considerable debate, with both plume and non-plume models invoked by many authors (e.g., Deruelle et al., 2007; Ngako et al, 2006; Ritsema and Allen, 2003; Burke, 2001; Ebinger and Sleep, 1998; Lee et al, 1994; Dorbath et al., 1986; Fairhead and Binks, 1991; King and Ritsema, 2000; Reusch et al., 2010). Crustal structure beneath Cameroon has been investigated previously using active (Stuart et al, 1985) and passive (Dorbath et al., 1986; Tabod, 1991; Tabod et al, 1992; Plomerova et al, 1993) source seismic data, revealing a crust about 33 km thick at the south-western end of the continental portion of the CVL (Tabod, 1991) and the Adamawa Plateau, and thinner crust (23 km thick) beneath the Garoua Rift in the north (Stuart et al, 1985) (Figure 1). Estimates of crustal thickness obtained using gravity data show similar variations between the Garoua rift, Adamawa Plateau, and southern part of the CVL (Poudjom et al., 1995; Nnange et al., 2000). In this study, we investigate further crustal structure beneath the CVL and the adjacent regions in

ISOLASI DAN IDENTIFIKASI SENYAWA KIMIA SERTA UJI AKTIVITAS ANTICANDIDAISIS SERBUK DAUN SIRIH DUDUK (Piper sarmentosum Roxb. Ex Hunter

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Suwandri Suwandri

2006-11-01

Full Text Available Sirih duduk or Piper sarmentosum Roxb. ex Hunter have been long used the people in Indonesia for traditional medicine to cure various diseases. One of them was used to treat fungoid diseases. This research was aimed to examine the anticandidaisis activity from extract of P. sarmentosum leaves and to isolate and identify the anticandidaisis compounds from P. sarmentosum leaves. The isolation bioactive compounds of P. sarmentosumleaves was performed by extraction the powder of P. sarmentosum leaves using methanol and the bioactivity tests were performed against Candida albicans. The methanol extracts was then fractionated using organic solvents such as n-hexane, benzene, chloroform, and ethyl acetate. Identification of the bioactive compounds was carried out using ultraviolet-visible spectrometry, fourier transform infra red spectrometry and gas chromatography-mass spectrometry. The result showed that the chloroform fraction of methanol extract of P. sarmentosum leaves have activity against C. albicans. The fractionation was performed by coloumn chromatography using n-hexane-ethyl acetate(1:1 eluent. A bioactive compound of sinamic acid derivative was 4-ethoxy-2-hidroxy-3,5-dimethoxy sinamic acid could be purely isolated.

Access to Electric Light Is Associated with Shorter Sleep Duration in a Traditionally Hunter-Gatherer Community.

Science.gov (United States)

de la Iglesia, Horacio O; Fernández-Duque, Eduardo; Golombek, Diego A; Lanza, Norberto; Duffy, Jeanne F; Czeisler, Charles A; Valeggia, Claudia R

2015-08-01

Access to electric light might have shifted the ancestral timing and duration of human sleep. To test this hypothesis, we studied two communities of the historically hunter-gatherer indigenous Toba/Qom in the Argentinean Chaco. These communities share the same ethnic and sociocultural background, but one has free access to electricity while the other relies exclusively on natural light. We fitted participants in each community with wrist activity data loggers to assess their sleep-wake cycles during one week in the summer and one week in the winter. During the summer, participants with access to electricity had a tendency to a shorter daily sleep bout (43 ± 21 min) than those living under natural light conditions. This difference was due to a later daily bedtime and sleep onset in the community with electricity, but a similar sleep offset and rise time in both communities. In the winter, participants without access to electricity slept longer (56 ± 17 min) than those with access to electricity, and this was also related to earlier bedtimes and sleep onsets than participants in the community with electricity. In both communities, daily sleep duration was longer during the winter than during the summer. Our field study supports the notion that access to inexpensive sources of artificial light and the ability to create artificially lit environments must have been key factors in reducing sleep in industrialized human societies. © 2015 The Author(s).

Preliminary assessment report for Army Aviation Support Facility No. 3, Installation 13307, Hunter Army Airfield, Savannah, Georgia

International Nuclear Information System (INIS)

Kolpa, R.; Smith, K.

1993-07-01

This report presents the results of the preliminary assessment (PA) conducted by Argonne National Laboratory at the Georgia Army National Guard property located on Hunter Army Airfield (HAA) near Savannah, Georgia, known as Army Aviation Support Facility (AASF) No. 3. Preliminary assessments of federal facilities are being conducted to compile the information necessary for completing preremedial activities and to provide a basis for establishing corrective actions in response to releases of hazardous substances. The principal objective of the PA is to characterize the site accurately and determine the need for further action by examining site activities, types and quantities of hazardous substances utilized, the nature and amounts of wastes generated or stored at the facility, and potential pathways by which contamination could affect public health and the environment. This PA satisfies, for the AASF No. 3 property, requirements of the Department of Defense Installation Restoration Program (IRP). The scope of this assessment is limited to the facilities and past activities contained within the area now occupied by AASF No. 3. However, this assessment report is intended to be read in conjunction with a previous IRP assessment of HAA completed in 1992 (USATHAMA 1992) and to provide comprehensive information on AASF No. 3 for incorporation with information contained in that previous assessment for the entirety of HAA

Three-Dimensional Seismic Tomography Beneath Tangshan, China

Science.gov (United States)

Chang, J. C.; Keranen, K. M.; Keller, G.; Qu, G.; Harder, S. H.

2010-12-01

The 1976 earthquake in Tangshan, China ranks as the deadliest earthquake in modern times. Though the exact number of casualties remains disputed, it is widely accepted that at least a quarter of a million people died. The high casualty level is surprising since the earthquake was not unusually large (Mw 7.5). Amplification of ground motion by thick sediment fill in the basin underlying the city is a likely cause for the extensive destruction. However, the extent of the unconsolidated material and the broader subsurface geology beneath Tangshan and surrounding areas needs to be better-constrained to properly model predicted ground motion and mitigate the hazards of future earthquakes. From a broader perspective, the Tangshan area is at the northern edge of the Bohai Bay basin province that has experienced both Cenozoic extension and related strike-slip tectonism. In January 2010, our group conducted a three-dimensional seismic investigation centered on the city of Tangshan. In an area of approximately 40 km x 60 km, we deployed 500 REFTEK 125A (“Texan”) recorders at 500 m spacing. A number of different sources, 20 altogether, were recorded during the two-day listening window, which include our large shots, smaller explosive shots from a co-spatial reflection survey, blasts from nearby quarries, and a small (Mearthquake. Our preliminary analyses suggest that the sediment fill is, on average, less than 1 km thick. Sediment fill is thinner to the north, as evidenced by outcropping bedrock, and thickens to the south. Sediment seismic velocity is about 1.8 km/s. Upper crustal velocities are 5.2 to 6.6 km/s, and increase to 7.0 km/s at mid-crustal depths.

Lithospheric strucutre and relationship to seismicity beneath the Southeastern US using reciever functions

Science.gov (United States)

Cunningham, E.; Lekic, V.

2017-12-01

Despite being on a passive margin for millions of years, the Southeastern United States (SEUS) contains numerous seismogenic zones with the ability to produce damaging earthquakes. However, mechanisms controlling these intraplate earthquakes are poorly understood. Recently, Biryol et al. 2016 use P-wave tomography suggest that upper mantle structures beneath the SEUS correlate with areas of seismicity and seismic quiescence. Specifically, thick and fast velocity lithosphere beneath North Carolina is stable and indicative of areas of low seismicity. In contrast, thin and slow velocity lithosphere is weak, and the transition between the strong and weak lithosphere may be correlated with seismogenic zones found in the SEUS. (eg. Eastern Tennessee seismic zone and the Central Virginia seismic zone) Therefore, I systematically map the heterogeneity of the mantle lithosphere using converted seismic waves and quantify the spatial correlation between seismicity and lithospheric structure. The extensive network of seismometers that makes up the Earthscope USArray combined with the numerous seismic deployments in the Southeastern United States allows for unprecedented opportunity to map changes in lithospheric structure across seismogenic zones and seismic quiescent regions. To do so, I will use both P-to-s and S-to-p receiver functions (RFS). Since RFs are sensitive to seismic wavespeeds and density discontinuities with depth, they particularly useful for studying lithospheric structure. Ps receiver functions contain high frequency information allowing for high resolution, but can become contaminated by large sediment signals; therefore, I removed sediment multiples and correct for time delays of later phases using the method of Yu et. al 2015 which will allow us to see later arriving phases associated with lithospheric discontinuities. S-to-p receiver functions are not contaminated by shallow layers, making them ideal to study deep lithospheric structures but they can

Tomographic Imaging of the Seismic Structure Beneath the East Anatolian Plateau, Eastern Turkey

Science.gov (United States)

Gökalp, Hüseyin

2012-10-01

The high level of seismic activity in eastern Turkey is thought to be mainly associated with the continuing collision of the Arabian and Eurasian tectonic plates. The determination of a detailed three-dimensional (3D) structure is crucial for a better understanding of this on-going collision or subduction process; therefore, a body wave tomographic inversion technique was performed on the region. The tomographic inversion used high quality arrival times from earthquakes occurring in the region from 1999 to 2001 recorded by a temporary 29 station broadband IRIS-PASSCAL array operated by research groups from the Universities of Boğaziçi (Turkey) and Cornell (USA). The data was inverted and consisted of 3,114 P- and 2,298 S-wave arrival times from 252 local events with magnitudes ( M D) ranging from 2.5 to 4.8. The stability and resolution of the results were qualitatively assessed by two synthetic tests: a spike test and checkerboard resolution test and it was found that the models were well resolved for most parts of the imaged domain. The tomographic inversion results reveal significant lateral heterogeneities in the study area to a depth of ~20 km. The P- and S-wave velocity models are consistent with each other and provide evidence for marked heterogeneities in the upper crustal structure beneath eastern Turkey. One of the most important features in the acquired tomographic images is the high velocity anomalies, which are generally parallel to the main tectonic units in the region, existing at shallow depths. This may relate to the existence of ophiolitic units at shallow depths. The other feature is that low velocities are widely dispersed through the 3D structure beneath the region at deeper crustal depths. This feature can be an indicator of the mantle upwelling or support the hypothesis that the Anatolian Plateau is underlain by a partially molten uppermost mantle.

The emergence of egalitarianism in a model of early human societies

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Guillaume Calmettes

2017-11-01

Full Text Available How did egalitarianism emerge in early human societies? In contrast to dominance hierarchies in non-human primates, human simple forager bands are typically egalitarian, with male hunters often serving as the collective alpha. Here we present a thermodynamics-inspired simple population model, based on stochastic optimization of dominance relationships, in which a dominance hierarchy of individuals with exclusively self-centered characteristics (the desire to dominate, resentment at being dominated transitions spontaneously to egalitarianism as their capacity for language develops. Language, specifically gossip, allows resentment against being dominated to promote the formation of antidominance coalitions which destabilize the alpha position for individuals, leading to a phase transition in which a coalition of the full population suddenly becomes dominant. Thus, egalitarianism emerges suddenly as the optimal power-sharing arrangement in a population of selfish individuals without any inherently altruistic qualities. We speculate that egalitarianism driven by punishment for exhibiting alpha-like behavior may then set the stage for genuinely altruistic traits to propagate as predicted by game theory models. Based on model simulations, we also predict that egalitarianism is a pre-condition for adaptation of tools as weapons. Potential implications for origins of human moral belief systems are discussed. Keywords: Sociology, Evolution, Anthropology

A new tomographic image on the Philippine Sea Slab beneath Tokyo - Implication to seismic hazard in the Tokyo metropolitan region -

Science.gov (United States)

Hirata, N.; Sakai, S.; Nakagawa, S.; Ishikawa, M.; Sato, H.; Kasahara, K.; Kimura, H.; Honda, R.

2012-12-01

In central Japan, the Philippine Sea plate (PSP) subducts beneath the Tokyo metropolitan region. Devastating M8-class earthquakes occurred on the upper surface of the Philippine Sea plate (SPS), examples of which are the Genroku earthquake of 1703 (magnitude M=8.0) and the Kanto earthquake of 1923 (M=7.9), which had 105,000 fatalities. A M7 or greater (M7+) earthquake in this region at present has high potential to produce devastating loss of life and property with even greater global economic repercussions although it is smaller than the megathrust type M8-class earthquakes. This great earthquake is evaluated to occur with a probability of 70 % in 30 years by the Earthquake Research Committee of Japan. The M7+ earthquakes may occur either on the upper surface or intra slab of PSP. The Central Disaster Management Council of Japan estimates the next great M7+ earthquake will cause 11,000 fatalities and 112 trillion yen (1 trillion US$) economic loss at worst case if it occur beneath northern Tokyo bay with M7.3. However, the estimate is based on a source fault model by conventional studies about the PSP geometry. To evaluate seismic hazard due to the great quake we need to clarify the geometry of PSP and also the Pacific palate (PAP) that subducs beneath PSP. We identify those plates with use of seismic tomography and available deep seismic reflection profiling and borehole data in southern Kanto area. We deployed about 300 seismic stations in the greater Tokyo urban region under the Special Project for Earthquake Disaster Mitigation in Tokyo Metropolitan Area. We obtain clear P- and S- wave velocity (Vp and Vs) tomograms which show a clear image of PSP and PAP. A depth to the top of PSP, 20 to 30 kilometer beneath northern part of Tokyo bay, is about 10 km shallower than previous estimates based on the distribution of seismicity (Ishida, 1992). This shallower plate geometry changes estimations of strong ground motion for seismic hazards analysis within the Tokyo

Mantle Convection beneath the Aegir Ridge, a Shadow in the Iceland Hotspot

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Howell, S. M.; Ito, G.; Breivik, A. J.; Hanan, B. B.; Mjelde, R.; Sayit, K.; Vogt, P. R.

2012-12-01

The Iceland Hotspot has produced extensive volcanism spanning much of the ocean basin between Greenland and Norway, forming one of the world's largest igneous provinces. However, an apparent igneous "shadow" in hotspot activity is located at the fossil Aegir Ridge, which formed anomalously thin crust, despite this ridge being near the Iceland hotspot when it was active. The Aegir Ridge accommodated seafloor spreading northeast of present-day Iceland from the time of continental breakup at ~55 Ma until ~25 Ma, at which point spreading shifted west to the Kolbeinsey Ridge. To address the cause of the anomalously thin crust produced by the Aegir Ridge, we use three-dimensional numerical models to simulate the interaction between a mantle plume beneath the Iceland hotspot, rifting continental lithosphere, and the time-evolving North Atlantic ridge system. Two end-member hypotheses were investigated: (1) Material emanating from the Iceland mantle plume was blocked from reaching the Aegir Ridge by the thick lithosphere of the Jan Mayen Microcontinent as the Kolbeinsey Ridge began rifting it from Greenland at ~30 Ma, just east of the plume center; (2) Plume material was not blocked and did reach the Aegir Ridge, but had already experienced partial melting closer to the hotspot. This material was then unable to produce melt volumes at the Aegir Ridge comparable to those of pristine mantle. To test these hypotheses, we vary the volume flux and viscosity of the plume, and identify which conditions do and do not lead to the Aegir Ridge forming anomalously thin crust. Results show that the combination of plume material being drawn into the lithospheric channels beneath the Reykjanes Ridge and Kolbeinsey Ridge after their respective openings, and the impedance of plume flow by the Jan Mayen Microcontinent (hypothesis 1), can deprive the Aegir Ridge of plume influence. This leads to low crustal thicknesses that are comparable to those observed. We have yet to produce a model

Spontaneous growth of whiskers from an interlayer of Mo sub 2 C beneath a diamond particle deposited in a combustion-flame

Energy Technology Data Exchange (ETDEWEB)

Okada, Katsuyuki; Komatsu, Shojiro; Ishigaki, Takamasa; Matsumoto, Seiichiro; Moriyoshi, Yusuke (National Inst. for Research in Inorganic Materials, Tsukuba, Ibaraki (Japan))

1992-02-01

When diamond particles deposited on a molybdenum substrate in a C{sub 2}H{sub -}O{sub 2} combustion-flame were kept for one year in the ambient atmosphere at room temperature, spontaneous whisker growth from an interlayer of Mo{sub 2}C beneath the diamond particles took place. The whiskers were clarified by electron probe micro-analysis (EPMA) and transmission electron microscopy (TEM) in a polycrystal composed of MoO{sub 2}, MoOC, and Mo{sub 2}C. The growth mechanism of them is discussed from two different points of view as follows: One is that the oxidation of an interlayer of Mo{sub 2}C beneath a diamond particle effectively reduces the surface free energy between the interlayer and diamond particle; consequently, the whisker can grow by using a screw dislocation. The other is that the internal stress existing between a diamond particle and an Mo{sub 2}C interlayer provides a very reactive zone where the growth of whisker takes place through the oxidation of Mo{sub 2}C. (orig.).

A Survey of Scattering, Attenuation, and Size Spectra Studies of Bubble Layers and Plumes Beneath the Air-Sea Interface.

Science.gov (United States)

1991-08-30

soluble iron in the ocean [201] - a factor which may have global ecological implications since these creatures may account for a significant removal...submerged plateau) and seamount -dense environments. In these contexts the existing measurements in lakes and shallow water need follow-up work in...Studies of Bubble Layers and Plumes Beneath the Air-Sea Interface EDWARD POWELL Acoustic Svstems Branch Acoustics Division August 30, 1991 Si~ T 91-10188

Seismic structure of the lithosphere beneath NW Namibia: Impact of the Tristan da Cunha mantle plume

Science.gov (United States)

Yuan, Xiaohui; Heit, Benjamin; Brune, Sascha; Steinberger, Bernhard; Geissler, Wolfram H.; Jokat, Wilfried; Weber, Michael

2017-01-01

Northwestern Namibia, at the landfall of the Walvis Ridge, was affected by the Tristan da Cunha mantle plume during continental rupture between Africa and South America, as evidenced by the presence of the Etendeka continental flood basalts. Here we use data from a passive-source seismological network to investigate the upper mantle structure and to elucidate the Cretaceous mantle plume-lithosphere interaction. Receiver functions reveal an interface associated with a negative velocity contrast within the lithosphere at an average depth of 80 km. We interpret this interface as the relic of the lithosphere-asthenosphere boundary (LAB) formed during the Mesozoic by interaction of the Tristan da Cunha plume head with the pre-existing lithosphere. The velocity contrast might be explained by stagnated and "frozen" melts beneath an intensively depleted and dehydrated peridotitic mantle. The present-day LAB is poorly visible with converted waves, indicating a gradual impedance contrast. Beneath much of the study area, converted phases of the 410 and 660 km mantle transition zone discontinuities arrive 1.5 s earlier than in the landward plume-unaffected continental interior, suggesting high velocities in the upper mantle caused by a thick lithosphere. This indicates that after lithospheric thinning during continental breakup, the lithosphere has increased in thickness during the last 132 Myr. Thermal cooling of the continental lithosphere alone cannot produce the lithospheric thickness required here. We propose that the remnant plume material, which has a higher seismic velocity than the ambient mantle due to melt depletion and dehydration, significantly contributed to the thickening of the mantle lithosphere.

Piecewise delamination of Moroccan lithosphere from beneath the Atlas Mountains

Science.gov (United States)

Bezada, M. J.; Humphreys, E. D.; Davila, J. M.; Carbonell, R.; Harnafi, M.; Palomeras, I.; Levander, A.

2014-04-01

The elevation of the intracontinental Atlas Mountains of Morocco and surrounding regions requires a mantle component of buoyancy, and there is consensus that this buoyancy results from an abnormally thin lithosphere. Lithospheric delamination under the Atlas Mountains and thermal erosion caused by upwelling mantle have each been suggested as thinning mechanisms. We use seismic tomography to image the upper mantle of Morocco. Our imaging resolves the location and shape of lithospheric cavities and of delaminated lithosphere ˜400 km beneath the Middle Atlas. We propose discontinuous delamination of an intrinsically unstable Atlas lithosphere, enabled by the presence of anomalously hot mantle, as a mechanism for producing the imaged structures. The Atlas lithosphere was made unstable by a combination of tectonic shortening and eclogite loading during Mesozoic rifting and Cenozoic magmatism. The presence of hot mantle sourced from regional upwellings in northern Africa or the Canary Islands enhanced the instability of this lithosphere. Flow around the retreating Alboran slab focused upwelling mantle under the Middle Atlas, which we infer to be the site of the most recent delamination. The Atlas Mountains of Morocco stand as an example of large-scale lithospheric loss in a mildly contractional orogen.

77 FR 47874 - National Register of Historic Places; Notification of Pending Nominations and Related Actions

Science.gov (United States)

2012-08-10

... Hall County Alta Vista Cemetery, 521 Jones St., Gainesville, 12000551 Troup County Eastside Historic...), 401 Jefferson, La Grange, 12000562 New Madrid County Hunter-Dawson House, 312 Dawson Rd., New Madrid... Puerto Rico TR), Georgetti St. No. 1, Barceloneta, 12000583 Cidra Municipality La Bolero (Early...

Seismic constraints on magma evolution beneath Mount Baekdu (Changbai) volcano from transdimensional Bayesian inversion of ambient noise data

Science.gov (United States)

Kim, Seongryong; Tkalčić, Hrvoje; Rhie, Junkee

2017-07-01

The magmatic process of continental intraplate volcanism (CIV) is difficult to understand due to heterogeneous interactions with the crust and the lithospheric upper mantle. Mount Baekdu (Changbai) volcano (MBV) is one of the prominent CIVs in northeast Asia that has shown a complex history of eruptions and associated magmatic structures. In addition, the relationship between the crustal magmatic structures and upper mantle phenomena are enigmatic due to the lack of consistent seismic constraints for the lithospheric structure. To enhance comprehensive understanding of the MBV magma evolution, we image the lithospheric structure beneath the MBV and surrounding regions using ambient noise data and the following two approaches: (1) multiple measures of ambient noise dispersion are acquired through different methods and (2) a transdimensional Bayesian inversion method is utilized to obtain unbiased results in joint analysis of the multiple data sets. The estimated Earth structure shows a thick crust ( 40 km) and a crustal anomaly with relatively high S wave velocity in the depth range 20-40 km. This type of structure extends to 100 km north from the MBV and is accompanied by the shallow and rapid S wave velocity decrease beneath the mantle lid ( 80 km). Through a comparison with previous P wave models, we interpret this structure as a consequence of compositional partitioning by mafic underplating and overlying cooled felsic layers as a result of fractional crystalization.

Remotely sensed soil temperatures beneath snow-free skin-surface using thermal observations from tandem polar-orbiting satellites: An analytical three-time-scale model

DEFF Research Database (Denmark)

Zhan, Wenfeng; Zhou, Ji; Ju, Weimin

2014-01-01

Subsurface soil temperature is a key variable of land surface processes and not only responds to but also modulates the interactions of energy fluxes at the Earth's surface. Thermal remote sensing has traditionally been regarded as incapable of detecting the soil temperature beneath the skin-surf...

The South Tibetan Tadpole Zone: Ongoing density sorting at the Moho beneath the Indus-Tsangpo suture zone (and beneath volcanic arcs?)

Science.gov (United States)

Kelemen, Peter; Hacker, Bradley

2016-04-01

Some Himalayan cross-sections show Indian crust thrust beneath Tibetan crust, with no intervening mantle wedge (e.g., Powell & Conaghan 73), others indicate thickening of both crustal sections, juxtaposed along a steep suture (e.g., Dewey & Burke 73), and many combine features of both end-members (e.g., Argand 24). To understand crustal scale structure and related phenomena, we focus on data from an area in southern Tibet at 28-30°N, 84-91°E. 21st century observations in this area show a horizontal Moho at ca 80 km depth, extending from thickened Indian crust, across a region where Tibetan crust is interpreted to overlie Indian crust, into thickened Tibetan crust (Zhao et al 01; Monsalve et al 08; Wittlinger et al 09; Nabelek et al 09; Kind et al 02; Schulte-Pelkum et al 05; Shi et al 15). About half the subducted Indian crustal volume is present, whereas the other half is missing (Replumaz et al 10). Vp/Vs indicates the alpha-beta quartz transition is at ca 50 km depth (Sheehan et al 13). Miocene lavas include primitive andesites probably formed by interaction of crustal material with mantle peridotite at > 1000°C (Turner et al 93; Williams et al 01, 04; Chung et al 05). Thermobarometry of xenoliths in a 12.7 Ma dike records ~ 1100°C at 2.2-2.6 GPa and 920°C at 1.7 GPa (Chan et al 09). Biotite-rich pyroxenites among the xenoliths, similar to those in central Tibet (Hacker et al 00) and the Pamirs (Hacker et al 05), may form via reaction of hot crustal lithologies and mantle peridotite (e.g., Sekine & Wyllie 82, 83). These data, taken together, indicate Miocene to present day temperatures exceeding 800°C from ca 50 km depth to the Moho, unlike thermal models with a hot mid-crust and cold Moho (McKenzie & Priestley 08, Craig et al 12, Wang et al 13; Nabelek & Nabelek 14), and despite the observation of numerous, near-Moho earthquakes (Chen & Molnar 83; Chen & Yang 04; Monsalve et al 06; Priestley et al 08; Craig et al 12) interpreted by many as brittle failure

Postcolonial Myth in Salman Rushdie’s The Ground Beneath Her Feet

Directory of Open Access Journals (Sweden)

Doncu Roxana Elena

2014-01-01

Full Text Available Postcolonial writers like Salman Rushdie often write back to the “empire” by appropriating myth and allegory. In The Ground beneath Her Feet, Rushdie rewrites the mythological story of Orpheus and Eurydice, using katabasis (the trope of the descent into Hell to comment both on the situation of the postcolonial writer from a personal perspective and to attempt a redefinition of postcolonial migrant identity-formation. Hell has a symbolic function, pointing both to the external context of globalization and migration (which results in the characters’ disorientation and to an interior space which can be interpreted either as a source of unrepressed energies and creativity (in a Romantic vein or as the space of the abject (in the manner of Julia Kristeva. The article sets out to investigate the complex ways in which the Orphic myth and katabasis are employed to shed light on the psychology of the creative artist and on the reconfiguration of identity that becomes the task of the postcolonial migrant subject. The journey into the underworld functions simultaneously as an allegory of artistic creation and identity reconstruction.

GATA2 is associated with familial early-onset coronary artery disease.

Directory of Open Access Journals (Sweden)

Jessica J Connelly

2006-08-01

Full Text Available The transcription factor GATA2 plays an essential role in the establishment and maintenance of adult hematopoiesis. It is expressed in hematopoietic stem cells, as well as the cells that make up the aortic vasculature, namely aortic endothelial cells and smooth muscle cells. We have shown that GATA2 expression is predictive of location within the thoracic aorta; location is suggested to be a surrogate for disease susceptibility. The GATA2 gene maps beneath the Chromosome 3q linkage peak from our family-based sample set (GENECARD study of early-onset coronary artery disease. Given these observations, we investigated the relationship of several known and novel polymorphisms within GATA2 to coronary artery disease. We identified five single nucleotide polymorphisms that were significantly associated with early-onset coronary artery disease in GENECARD. These results were validated by identifying significant association of two of these single nucleotide polymorphisms in an independent case-control sample set that was phenotypically similar to the GENECARD families. These observations identify GATA2 as a novel susceptibility gene for coronary artery disease and suggest that the study of this transcription factor and its downstream targets may uncover a regulatory network important for coronary artery disease inheritance.

If Hunters End Up in the Emergency Room: A Retrospective Analysis of Hunting Injuries in a Swiss Emergency Department

Directory of Open Access Journals (Sweden)

Valentina Bestetti

2015-01-01

Full Text Available Aim. to characterize the mechanisms, patterns, and outcomes of nonfatal hunting-related injuries in patients presenting to Bern University Hospital, Switzerland, and compare these to reports of hunting injuries worldwide. Methods. patients presenting with hunting-related injuries to the Emergency Department at Bern University hospital from 2000 to 2014 were identified by retrospectively searching the department database using the keyword “hunt.” Each case was analyzed in terms of the patient age and gender, the mechanism and pattern of injury, and management and patient follow-up. Results. 19 patients were identified. 16 were male with a mean age of 50 years (range: 16–74. Mechanisms of injury included firearm-related injuries, falls, and knife wounds. The most common patterns of injury were head injuries (7, followed by injuries to the upper (5 or lower limb (5 and trunk (2. Over half of the patients were admitted, and nine required emergency surgery. Conclusion. Nonfatal hunting accidents in Bern, Switzerland, are largely caused by firearms and falls and tend to occur in male hunters with a mean age of 50 years. The most common patterns of injury are orthopedic and head injuries, often requiring surgery. These findings are consistent with international studies of nonfatal hunting accidents.

Philippine Sea Plate inception, evolution, and consumption with special emphasis on the early stages of Izu-Bonin-Mariana subduction

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Lallemand, Serge

2016-12-01

We compiled the most relevant data acquired throughout the Philippine Sea Plate (PSP) from the early expeditions to the most recent. We also analyzed the various explanatory models in light of this updated dataset. The following main conclusions are discussed in this study. (1) The Izanagi slab detachment beneath the East Asia margin around 60-55 Ma likely triggered the Oki-Daito plume occurrence, Mesozoic proto-PSP splitting, shortening and then failure across the paleo-transform boundary between the proto-PSP and the Pacific Plate, Izu-Bonin-Mariana subduction initiation and ultimately PSP inception. (2) The initial splitting phase of the composite proto-PSP under the plume influence at ˜54-48 Ma led to the formation of the long-lived West Philippine Basin and short-lived oceanic basins, part of whose crust has been ambiguously called "fore-arc basalts" (FABs). (3) Shortening across the paleo-transform boundary evolved into thrusting within the Pacific Plate at ˜52-50 Ma, allowing it to subduct beneath the newly formed PSP, which was composed of an alternance of thick Mesozoic terranes and thin oceanic lithosphere. (4) The first magmas rising from the shallow mantle corner, after being hydrated by the subducting Pacific crust beneath the young oceanic crust near the upper plate spreading centers at ˜49-48 Ma were boninites. Both the so-called FABs and the boninites formed at a significant distance from the incipient trench, not in a fore-arc position as previously claimed. The magmas erupted for 15 m.y. in some places, probably near the intersections between back-arc spreading centers and the arc. (5) As the Pacific crust reached greater depths and the oceanic basins cooled and thickened at ˜44-45 Ma, the composition of the lavas evolved into high-Mg andesites and then arc tholeiites and calc-alkaline andesites. (6) Tectonic erosion processes removed about 150-200 km of frontal margin during the Neogene, consuming most or all of the Pacific ophiolite

Managing and mitigating extensive subsurface fuel product beneath two inner-city heritage buildings

Energy Technology Data Exchange (ETDEWEB)

Friedrich, K. [City of Edmonton, AB (Canada); Morton, P.R. [EBA Engineering Consultants Ltd., Edmonton, AB (Canada)

2006-07-01

The management and mitigation of extensive subsurface fuel product beneath two inner-city heritage buildings in Edmonton, Alberta was examined. The presentation was organized under four components: description and planning; scope and risk; design; and implementation. The description and planning section identified the location, buildings, stakeholders, and integration with other activities. The section on scope and risk addressed issues regarding hydrocarbon impacts, remediation ranking (vertical and inclined wells and horizontal wells), remediation modes, and field trials. The section on design identified the remediation components including extraction wells; liquids separation and collection; water treatment; off-gas catalytic oxidation; sensor data acquisition and PLCS system; satellite link for web monitoring and control, and secure and noise-reducing enclosure. Implementation issues were also discussed with reference to horizontal directional drilling and well construction, difficulties and problems, commissioning, remediation progress to-date, and community benefits. tabs., figs.

230Th-238U disequilibrium and the melting processes beneath ridge axes

International Nuclear Information System (INIS)

McKenzie, D.

1985-01-01

The activity ratio ( 230 Th/ 238 U) is calculated for a simple model of melting, for which the melt fraction in chemical and radioactive equilibrium with the solid residium remains constant as melting proceeds. The activity ratio in the melt is only significantly different from unity if the melting is slow compared with the half-life of 230 Th and if the melt fraction present at any time does not exceed a few percent. The observation that ( 230 Th/ 238 U) is about 1.25 for many ocean ridge basalts is therefore most easily explained if the melt fraction in the source region is less than 2% and if the melting occurs in a broad region more than 100 km wide beneath the ridge axis. These results are compatible with other geophysical observations. Measurements of ( 226 Ra/ 238 U) might provide useful constraints on the time required to reach chemical equilibrium between the melt and the matrix. (orig.)

Hunter-gatherer postcranial robusticity relative to patterns of mobility, climatic adaptation, and selection for tissue economy.

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Stock, J T

2006-10-01

Human skeletal robusticity is influenced by a number of factors, including habitual behavior, climate, and physique. Conflicting evidence as to the relative importance of these factors complicates our ability to interpret variation in robusticity in the past. It remains unclear how the pattern of robusticity in the skeleton relates to adaptive constraints on skeletal morphology. This study investigates variation in robusticity in claviculae, humeri, ulnae, femora, and tibiae among human foragers, relative to climate and habitual behavior. Cross-sectional geometric properties of the diaphyses are compared among hunter-gatherers from southern Africa (n = 83), the Andaman Islands (n = 32), Tierra del Fuego (n = 34), and the Great Lakes region (n = 15). The robusticity of both proximal and distal limb segments correlates negatively with climate and positively with patterns of terrestrial and marine mobility among these groups. However, the relative correspondence between robusticity and these factors varies throughout the body. In the lower limb, partial correlations between polar second moment of area (J(0.73)) and climate decrease from proximal to distal section locations, while this relationship increases from proximal to distal in the upper limb. Patterns of correlation between robusticity and mobility, either terrestrial or marine, generally increase from proximal to distal in the lower and upper limbs, respectively. This suggests that there may be a stronger relationship between observed patterns of diaphyseal hypertrophy and behavioral differences between populations in distal elements. Despite this trend, strength circularity indices at the femoral midshaft show the strongest correspondence with terrestrial mobility, particularly among males.

Genomic insights into the origin and diversification of late maritime hunter-gatherers from the Chilean Patagonia.

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de la Fuente, Constanza; Ávila-Arcos, María C; Galimany, Jacqueline; Carpenter, Meredith L; Homburger, Julian R; Blanco, Alejandro; Contreras, Paloma; Cruz Dávalos, Diana; Reyes, Omar; San Roman, Manuel; Moreno-Estrada, Andrés; Campos, Paula F; Eng, Celeste; Huntsman, Scott; Burchard, Esteban G; Malaspinas, Anna-Sapfo; Bustamante, Carlos D; Willerslev, Eske; Llop, Elena; Verdugo, Ricardo A; Moraga, Mauricio

2018-04-24

Patagonia was the last region of the Americas reached by humans who entered the continent from Siberia ∼15,000-20,000 y ago. Despite recent genomic approaches to reconstruct the continental evolutionary history, regional characterization of ancient and modern genomes remains understudied. Exploring the genomic diversity within Patagonia is not just a valuable strategy to gain a better understanding of the history and diversification of human populations in the southernmost tip of the Americas, but it would also improve the representation of Native American diversity in global databases of human variation. Here, we present genome data from four modern populations from Central Southern Chile and Patagonia ( n = 61) and four ancient maritime individuals from Patagonia (∼1,000 y old). Both the modern and ancient individuals studied in this work have a greater genetic affinity with other modern Native Americans than to any non-American population, showing within South America a clear structure between major geographical regions. Native Patagonian Kawéskar and Yámana showed the highest genetic affinity with the ancient individuals, indicating genetic continuity in the region during the past 1,000 y before present, together with an important agreement between the ethnic affiliation and historical distribution of both groups. Lastly, the ancient maritime individuals were genetically equidistant to a ∼200-y-old terrestrial hunter-gatherer from Tierra del Fuego, which supports a model with an initial separation of a common ancestral group to both maritime populations from a terrestrial population, with a later diversification of the maritime groups.

Potential Magma Chambers beneath the Tatun Volcanic Area, Taiwan: Results from Magnetotelluric Survey and Monitoring

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Chen, C.

2013-12-01

Previous earthquakes analysis indicated existing seismicity anomaly beneath Tatun volcano, Taiwan, possibly caused by the fluid activity of the volcano. Helium isotope studies also indicated that over 60% of the fumarolic gases and vapors originated from deep mantle in the Tatun volcano area. The chemistry of the fumarolic gases and vapors and seismicity anomaly are important issues in view of possible magma chamber in the Tatun volcano, where is in the vicinity of metropolitan Taipei, only 15 km north of the capital city. In this study magnetotelluric (MT) soundings and monitoring were deployed to understand the geoelectric structures in the Tatun volcano as Electromagnetic methods are sensitive to conductivity contrasts and can be used as a supplementary tool to delineate reservoir boundaries. An anticline extending more than 10 km beneath the Chih-Shin-Shan and Da-You-Kan areas was recognized. Low resistivity at a shallow and highly porous layer 500m thick might indicate circulation of heated water. However, a high resistivity layer at depth between 2 and 6 km was detected. This layer could be associated with high micro-earthquakes zone. The characteristics of this layer produced by either the magma chamber or other geothermal activity were similar to that of some other active volcanic areas in the world. At 6 km underground was a dome structure of medium resistivity. This structure could be interpreted as a magma chamber in which the magma is possibly cooling down, as judged by its relatively high resistivity. The exact attributes of the magma chamber were not precisely determined from the limited MT soundings. At present, a joint monitors including seismic activity, ground deformation, volcanic gases, and changes in water levels and chemistry are conducted by universities and government agencies. When unusual activity is detected, a response team may do more ground surveys to better determine if an eruption is likely.

Effects of reperfusion intervals on skeletal muscle injury beneath and distal to a pneumatic tourniquet.

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Pedowitz, R A; Gershuni, D H; Fridén, J; Garfin, S R; Rydevik, B L; Hargens, A R

1992-03-01

To date there have been no experimental studies specifically directed at effects of reperfusion intervals on skeletal muscle injury beneath the tourniquet. 99mTechnetium pyrophosphate (Tc 99) incorporation and correlative histology were used to assess injury 2 days after tourniquet application in muscles beneath (thigh) and distal (leg) to the cuff. Tourniquets were applied to rabbit hindlimbs for a total of either 2 or 4 hours. In the 4-hour series, tourniquet compression (either 125 mm Hg or 350 mm Hg cuff inflation pressure) was either continuous or interrupted by 10-minute reperfusion intervals after 2 hours or after every hour of cuff inflation. In the 2-hour series, tourniquet compression (350 mm Hg) was either continuous or interrupted by 10-minute reperfusion intervals after 2 hours or after every hour of cuff inflation. In the 2-hour series, tourniquet compression (350 mm Hg) was either continuous or interrupted by a 10-minute reperfusion interval after 1 hour. Pyrophosphate incorporation (Tc 99 uptake) was significantly greater in the thigh region than in the leg region in all of the 4-hour tourniquet groups. Tc 99 uptake was significantly reduced by reperfusion after each hour of cuff inflation. With 350 mm Hg tourniquet pressure, a reperfusion interval after 2 hours of cuff inflation tended to exacerbate tourniquet compression injury. Reperfusion intervals did not significantly affect Tc 99 uptake in the leg region of these groups. With a 2-hour tourniquet time, Tc 99 uptake in the thigh was significantly decreased by reperfusion after 1 hour of cuff inflation. Previous clinical recommendations, based on serum creatine phosphokinase abnormalities after experimental tourniquet ischemia, probably reflected tourniquet compression injury. Hourly reperfusion limits skeletal muscle injury during extended periods of tourniquet use.

Geophysical investigation of seepage beneath an earthen dam.

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Ikard, S J; Rittgers, J; Revil, A; Mooney, M A

2015-01-01

A hydrogeophysical survey is performed at small earthen dam that overlies a confined aquifer. The structure of the dam has not shown evidence of anomalous seepage internally or through the foundation prior to the survey. However, the surface topography is mounded in a localized zone 150 m downstream, and groundwater discharges from this zone periodically when the reservoir storage is maximum. We use self-potential and electrical resistivity tomography surveys with seismic refraction tomography to (1) determine what underlying hydrogeologic factors, if any, have contributed to the successful long-term operation of the dam without apparent indicators of anomalous seepage through its core and foundation; and (2) investigate the hydraulic connection between the reservoir and the seepage zone to determine whether there exists a potential for this success to be undermined. Geophysical data are informed by hydraulic and geotechnical borehole data. Seismic refraction tomography is performed to determine the geometry of the phreatic surface. The hydro-stratigraphy is mapped with the resistivity data and groundwater flow patterns are determined with self-potential data. A self-potential model is constructed to represent a perpendicular profile extending out from the maximum cross-section of the dam, and self-potential data are inverted to recover the groundwater velocity field. The groundwater flow pattern through the aquifer is controlled by the bedrock topography and a preferential flow pathway exists beneath the dam. It corresponds to a sandy-gravel layer connecting the reservoir to the downstream seepage zone. © 2014, National Ground Water Association.

Seismic anisotropy in the upper mantle beneath the MAGIC array, mid-Atlantic Appalachians: Constraints from SKS splitting and quasi-Love wave propagation

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Aragon, J. C.; Long, M. D.; Benoit, M. H.; Servali, A.

2016-12-01

North America's eastern passive continental margin has been modified by several cycles of supercontinent assembly. Its complex surface geology and distinct topography provide evidence of these events, while also raising questions about the extent of deformation in the continental crust, lithosphere, and mantle during past episodes of rifting and mountain building. The Mid-Atlantic Geophysical Integrative Collaboration (MAGIC) is an EarthScope and GeoPRISMS-funded project that involves a collaborative effort among seismologists, geodynamicists, and geomorphologists. One component of the project is a broadband seismic array consisting of 28 instruments in a linear path from coastal Virginia to western Ohio, which operated between October 2013 and October 2016. A key science question addressed by the MAGIC project is the geometry of past lithospheric deformation and present-day mantle flow beneath the Appalachians, which can be probed using observations of seismic anisotropy Here we present observations of SKS splitting and quasi-Love wave arrivals from stations of the MAGIC array, which together constrain seismic anisotropy in the upper mantle. SKS splitting along the array reveals distinct regions of upper mantle anisotropy, with stations in and to the west of the range exhibiting fast directions parallel to the strike of the mountains. In contrast, weak splitting and null SKS arrivals dominate eastern stations in the coastal plain. Documented Love-to-Rayleigh wave scattering for surface waves originating the magnitude 8.3 Illapel, Chile earthquakes in September 2015 provides complementary constraints on anisotropy. These quasi-Love wave arrivals suggest a pronounced change in upper mantle anisotropy at the eastern edge of present-day Appalachian topography. Together, these observations increase our understanding of the extent of lithospheric deformation beneath North America associated with Appalachian orogenesis, as well as the pattern of present-day mantle flow

Imaging pockets and conduits of low velocity material beneath the lithosphere of the Atlas Mountains of Morocco: links to volcanism and orogenesis

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Miller, M. S.; Sun, D.; O'Driscoll, L.; Holt, A.; Butcher, A.; Becker, T. W.; Diaz Cusi, J.; Thomas, C.

2014-12-01

The Atlas Mountains of Morocco have unusually high topography, with no apparent deep crustal root, and regions of localized Cenozoic alkaline volcanism. Previous seismic imaging and geophysical studies have implied a hot mantle upwelling as the source of the volcanism and high elevation, but the existence and physical properties of such an upwelling are debated. Recent temporary deployments of over 100 broadband seismometers that extended across Morocco as part of the PICASSO, Morocco-Münster, and IberArray experiments along with select permanent stations have provided a dataset to image the detailed mantle and lithospheric structure beneath the Atlas. We present results from S receiver functions (SRF), shear wave splitting, waveform modeling, and geodynamic models that help constrain the tectonic evolution of the Atlas and the localized alkaline volcanism. The receiver functions show that the lithosphere is thin (~65 km) beneath the Atlas, but thickens (~105 km) over a very short length scale at the flanks of the mountains and near the Quaternary volcanoes. These changes in lithospheric thickness also correspond to dramatic decreases in delay times inferred from S and SKS splitting observations. SRFs also indicate a broad, low seismic velocity anomaly (~150 km) below the shallow lithosphere that extends along much of the Atlas and beneath the Anti-Atlas and correlates with the location of Pliocene-Quaternary magmatism. Waveform analysis from the linear array across the Middle and High Atlas constrains the position, shape, and physical characteristics of a localized, low velocity conduit that extends up from the uppermost mantle (~200 km). The shape, position and temperature of the imaged low velocity anomaly, offsets in the lithosphere-asthenosphere boundary, and correlation with mantle flow inferred from shear wave splitting suggest that the unusually high topography of the Atlas Mountains is due to active mantle support.

Variable crustal thickness beneath Thwaites Glacier revealed from airborne gravimetry, possible implications for geothermal heat flux in West Antarctica

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Damiani, Theresa M.; Jordan, Tom A.; Ferraccioli, Fausto; Young, Duncan A.; Blankenship, Donald D.

2014-12-01

Thwaites Glacier has one of the largest glacial catchments in West Antarctica. The future stability of Thwaites Glacier's catchment is of great concern, as this part of the West Antarctic Ice Sheet has recently been hypothesized to already be en route towards collapse. Although an oceanic trigger is thought to be responsible for current change at the grounding line of Thwaites Glacier, in order to determine the effects of this coastal change further in the interior of the West Antarctic Ice Sheet it is essential to also better constrain basal conditions that control the dynamics of fast glacial flow within the catchment itself. One major contributor to fast glacial flow is the presence of subglacial water, the production of which is a result of both glaciological shear heating and geothermal heat flux. The primary goal of our study is to investigate the crustal thickness beneath Thwaites Glacier, which is an important contributor to regional-scale geothermal heat flux patterns. Crustal structure is an indicator of past tectonic events and hence provides a geophysical proxy for the thermal status of the crust and mantle. Terrain-corrected Bouguer gravity disturbances are used here to estimate depths to the Moho and mid-crustal boundary. The thin continental crust we reveal beneath Thwaites Glacier supports the hypothesis that the West Antarctic Rift System underlies the region and is expressed topographically as the Byrd Subglacial Basin. This rifted crust is of similar thickness to that calculated from airborne gravity data beneath neighboring Pine Island Glacier, and is more extended than crust in the adjacent Siple Coast sector of the Ross Sea Embayment. A zone of thinner crust is also identified near the area's subaerial volcanoes lending support to a recent interpretation predicting that this part of Marie Byrd Land is a major volcanic dome, likely within the West Antarctic Rift System itself. Near-zero Bouguer gravity disturbances for the subglacial highlands

Soil water storage and groundwater behaviour in a catenary sequence beneath forest in central Amazonia: I. Comparisons between plateau, slope and valley floor

Directory of Open Access Journals (Sweden)

M. G. Hodnett

1997-01-01

Full Text Available Soil water storage was monitored in three landscape elements in the forest (plateau, slope and valley floor over a 3 year period to identify differences in sub-surface hydrological response. Under the plateau and slope, the changes of storage were very similar and there was no indication of surface runoff on the slope. The mean maximum seasonal storage change was 156 mm in the 2 m profile but it was clear that, in the dry season, the forest was able to take up water from below 3.6 m. Soil water availability was low. Soil water storage changes in the valley were dominated by the behaviour of a shallow water table which, in normal years, varied between 0.1 m below the surface at the end of the wet season and 0.8 m at the end of the dry season. Soil water storage changes were small because root uptake was largely replenished by groundwater flow towards the stream. The groundwater behaviour is controlled mainly by the deep drainage from beneath the plateau and slope areas. The groundwater gradient beneath the slope indicated that recharge beneath the plateau and slope commences only after the soil water deficits from the previous dry season have been replenished. Following a wet season with little recharge, the water table fell, ceasing to influence the valley soil water storage, and the stream dried up. The plateau and slope, a zone of very high porosity between 0.4 and 1.1 m, underlain by a less conductive layer, is a probable route for interflow during, and for a few hours after, heavy and prolonged rainfall.

Asthenospheric counterflows beneath the moving lithosphere of Central and East Asia in the past 90 Ma: volcanic and tomographic evidence

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Rasskazov, Sergei; Chuvashova, Irina; Kozhevnikov, Vladimir

2015-04-01

Asthenospheric counterflows, accompanied motions of the lithosphere in Central and East Asia, are defined on basis of spatial-temporal activity of mantle sources [Rasskazov et al., 2012; Rasskazov, Chuvashova, 2013; Chuvashova, Rasskazov, 2014] and the tomographic model of the Rayleigh wave group velocities [Kozhevnikov et al., 2014]. The opposite fluxes are defined relative to centers of convective instability (low-velocity anomalies), expressed by thinning of the mantle transition layer under Southwestern Gobi (44 °N, 95 °E) and Northern Baikal (52 °N, 108 °E). Cretaceous-Paleogene volcanic fields in Southern Gobi are shifted eastwards relative to the former anomaly over 600 km with the opposite sub-lithospheric flux at depths of 150-300 km. Likewise, the Late Tertiary Vitim volcanic field is shifted relative to the latter anomaly over 100-200 km. We suggest that the Gobi and Baikal asthenospheric counterflows contributed to the rollback mechanism of downgoing slab material from the Pacific under the eastern margin of Asia in the Cretaceous-Paleogene and Early-Middle Miocene. The east-west Gobi reverse flux, caused by differential block motions in front of the Indo-Asian convergence, resulted in the oblique Honshu-Korean flexure of the Pacific slab that propagated beneath the continental margin, while the Japan Sea was quickly opening at about 15 Ma. The Baikal N60°W reverse flux, originated due to oncoming traffic between Eurasia and the Pacific plate, entailed the formation of the Baikal Rift Zone and direct Hokkaido Amur slab flexure [Rasskazov et al., 2004]. The study is supported by the Russian Foundation for Basic Research (Grant 14-05-31328). References Chuvashova I.S., Rasskazov S.V. Magmatic sources in the mantle of the evolving Earth. Irkutsk: Publishing House of the Irkutsk State University, 2014. 310 p. (in Russian) Kozhevnikov V.M., Seredkina A.I., Solovei O.A. 3D mantle structure of Central Asia from Rayleigh wave group velocity dispersion

Eocene lake basins in Wyoming and Nevada record rollback of the Farallon flat-slab beneath western North America

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Smith, M. E.; Cassel, E. J.; Jicha, B. R.; Singer, B. S.; Carroll, A.

2014-12-01

Numerical and conceptual models of flat-slab rollback predict broad initial dynamic subsidence above the slab hinge then uplift and volcanism triggered by the advection of asthenosphere beneath the overriding plate. These predicted surface effects provide a viable but largely untested explanation for lake basin formation in Cordilleran-type orogenies. We argue that the hydrologic closure of both the foreland (early Eocene) and hinterland (late Eocene) of the North American Cordillera were caused by a trenchward-migrating wave of dynamic and thermal topography resulting from progressive removal of the Farallon flat-slab. Two major episodes of hydrologic drainage closure are recorded by Eocene terrestrial strata in the western United States. The first occurred in the retroarc foreland during the early Eocene, and resulted in the deposition of the Green River Fm. The second occurred in the hinterland during the late Eocene and resulted in accumulation of the Elko Fm. In both regions, lake strata overlie fluvial strata and become progressively more evaporative up-section, and are overlain by volcaniclastic strata. Both successions were then truncated by regional unconformities that extend until the Oligocene. We interpret these stratigraphic successions to record trenchward propagation of a regional topographic wave, caused by slab rollback. Migration of the slab-hinge initially caused dynamic subsidence and initiation of lacustrine deposition. Regional surface uplift followed, and was associated with scattered volcanism. Uplift promoted formation of endorheic basins and ultimately the development of regional unconformities. The height of the uplift can be roughly approximated by the preserved thickness of lacustrine and other nonmarine deposits at both locations (0.2-1.0 km). The 40Ar/39Ar and U-Pb geochronology of Green River Fm ash beds indicate that this surface topographic wave migrated trenchward (SW) across the foreland from 53 to 47 Ma at a velocity of ~6 cm

Complex Crustal Structure Beneath Western Turkey Revealed by 3D Seismic Full Waveform Inversion (FWI)

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Cubuk-Sabuncu, Yesim; Taymaz, Tuncay; Fichtner, Andreas

2016-04-01

We present a 3D radially anisotropic velocity model of the crust and uppermost mantle structure beneath the Sea of Marmara and surroundings based on the full waveform inversion method. The intense seismic activity and crustal deformation are observed in the Northwest Turkey due to transition tectonics between the strike-slip North Anatolian Fault (NAF) and the extensional Aegean region. We have selected and simulated complete waveforms of 62 earthquakes (Mw > 4.0) occurred during 2007-2015, and recorded at (Δ Technological Research Council of Turkey (TUBITAK Project No: ÇAYDAG-114Y066), and EU-HORIZON-2020: COST Actions: Earth System Science and Environmental Management: ES1401 - Time Dependent Seismology (TIDES).

Geochronology and geochemistry of early Paleozoic intrusive rocks from the Khanka Massif in the Russian Far East: Petrogenesis and tectonic implications

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Xu, Ting; Xu, Wen-Liang; Wang, Feng; Ge, Wen-Chun; Sorokin, A. A.

2018-02-01

This paper presents new geochronological and geochemical data for early Paleozoic intrusive rocks from the Khanka Massif in the Russian Far East, with the aim of elucidating the Paleozoic evolution and tectonic attributes of the Khanka Massif. New U-Pb zircon data indicate that early Paleozoic magmatism within the Khanka Massif can be subdivided into at least four stages: 502, 492, 462-445, and 430 Ma. The 502 Ma pyroxene diorites contain 58.28-59.64 wt% SiO2, 2.84-3.69 wt% MgO, and relatively high Cr and Ni contents. Negative εHf(t) values (- 1.8 to - 0.4), along with other geochemical data, indicate that the primary magma was derived from partial melting of mafic lower crust with the addition of mantle material. The 492 Ma syenogranites have high SiO2 and K2O contents, and show positive Eu anomalies, indicating the primary magma was generated by partial melting of lower crust at relatively low pressure. The 445 Ma Na-rich trondhjemites display high Sr/Y ratios and positive εHf(t) values (+ 1.8 to + 3.9), indicating the primary magma was generated by partial melting of thickened hydrous mafic crust. The 430 Ma granitoids have high SiO2 and K2O contents, zircon εHf(t) values of - 5.4 to + 5.8, and two-stage model ages of 1757-1045 Ma, suggesting the primary magma was produced by partial melting of heterogeneous Proterozoic lower crustal material. The geochemistry of these early Paleozoic intrusive assemblages indicates their formation in an active continental margin setting associated with the subduction of a paleo-oceanic plate beneath the Khanka Massif. The εHf(t) values show an increasingly negative trend with increasing latitude, revealing a lateral heterogeneity of the lower crust beneath the Khanka Massif. Regional comparisons of the magmatic events indicate that the Khanka Massif in the Russian Far East has a tectonic affinity to the Songnen-Zhangguangcai Range Massif rather than the adjacent Jiamusi Massif.

Lithospheric flexure beneath the Freyja Montes Foredeep, Venus: Constraints on lithospheric thermal gradient and heat flow

International Nuclear Information System (INIS)

Solomon, S.C.; Head, J.W.

1990-01-01

Analysis of Venera 15 and 16 radar images and topographic data from the Freyja Montes region on Venus suggest that this mountain belt formed as a result of a sequence of underthrusts of the lithosphere of the North Polar Plains beneath the highlands of Ishtar Terra. The Freyja Montes deformation zone consists, south to north, of a linear orogenic belt, an adjacent plateau, a steep scarp separating the plateau from the North Polar Plains, a linear depression at the base of the scarp, and an outer rise. The topographic profile of the depression and outer rise are remarkably similar to that of a foreland deep and rise formed by the flexure of the underthrusting plate beneath a terrestrial mountain range. The authors test the lithospheric flexure hypothesis and they estimate the effective thickness T e of the elastic lithosphere of the underthrusting portion of the North Polar Plains by fitting individual topographic profiles to deflection curves for a broken elastic plate. The theoretical curves fit the observed topographic profiles to within measurement error for values of flexural rigidity D in the range (0.8-3) x 10 22 N m, equivalent to T e in the range 11-18 km. Under the assumption that the base of the mechanical lithosphere is limited by the creep strength of olivine, the mean lithospheric thermal gradient is 14-23 K/km. That the inferred thermal gradient is similar to the value expected for the global mean gradient on the basis of scaling from Earth provides support for the hypothesis that simple conduction dominates lithospheric heat transport on Venus relative to lithospheric recycling and volcanism

Constraints of texture and composition of clinopyroxene phenocrysts of Holocene volcanic rocks on a magmatic plumbing system beneath Tengchong, SW China

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Hu, Jun-Hao; Song, Xie-Yan; He, Hai-Long; Zheng, Wen-Qin; Yu, Song-Yue; Chen, Lie-Meng; Lai, Chun-Kit

2018-04-01

Understanding processes of magma replenishment in a magma plumbing system is essential to predict eruption potential of a dormant volcano. In this study, we present new petrologic and thermobarometric data for youngest lava flows from the Holocene Heikongshan volcano in the Tengchong area, SW China. Clinopyroxene phenocrysts from the trachytic lava flows display various textural/compositional zoning styles (i.e., normal, reverse and oscillatory). Such zoning patterns are indicative of an open magmatic plumbing system with multiphase magma replenishment and mixing, which were likely a key drive of the volcanic eruptions. Thermobarometric calculations of these zoned clinopyroxene phenocrysts yield crystallization pressures of 3.8-7.1 kbar (peak at 4.5-7.0 kbar), corresponding to a magma chamber at depths of 14-21 km. The calculated depths are consistent with the large low-resistivity body at 12-30 km beneath the Heikongshan volcano, implying that the magmatic plumbing system may still be active. Recent earthquakes in the Tengchong area suggest that the regional strike-slip faulting are still active, and may trigger future volcanic eruptions if the magma chamber(s) beneath the Tengchong volcanic field is disturbed, in spite of the volcanic quiescence since 1609 CE.

New seismic observation on the lithosphere and slab subduction beneath the Indo-Myanmar block: Implications for continent oblique subduction and transition to oceanic slab subduction

Science.gov (United States)

Jiang, M.; He, Y.; Zheng, T.; Mon, C. T.; Thant, M.; Hou, G.; Ai, Y.; Chen, Q. F.; Sein, K.

2017-12-01

The Indo-Myanmar block locates to the southern and southeastern of the Eastern Himalayan Syntax (EHS) and marks a torsional boundary of the collision between the Indian and Eurasian plates. There are two fundamental questions concerned on the tectonics of Indo-Myanmar block since the Cenozoic time. One is whether and how the oblique subduction is active in the deep; the other is where and how the transition from oceanic subduction and continental subduction operates. However, the two problems are still under heated debate mainly because the image of deep structure beneath this region is still blurring. Since June, 2016, we have executed the China-Myanmar Geophysical Survey in the Myanmar Orogen (CMGSMO) and deployed the first portable seismic array in Myanmar in cooperation with Myanmar Geosciences Society (MGS). This array contains 70 stations with a dense-deployed main profile across the Indo-Myanmar Range, Central Basin and Shan State Plateau along latitude of 22° and a 2-D network covering the Indo-Myanmar Range and the western part of the Central Basin. Based on the seismic data collected by the new array, we conducted the studies on the lithospheric structure using the routine surface wave tomography and receiver function CCP stacking. The preliminary results of surface wave tomography displayed a remarkable high seismic velocity fabric in the uppermost of mantle beneath the Indo-Myanmar Range and Central Basin, which was interpreted as the subducted slab eastward. Particularly, we found a low velocity bulk within the high-velocity slab, which was likely to be a slab window due to the slab tearing. The preliminary results of receiver function CCP stacking showed the obvious variations of the lithospheric structures from the Indo-Myanmar Range to the Central Basin and Shan State Plateau. The lithospheric structure beneath the Indo-Myanmar Range is more complex than that beneath the Central Basin and Shan State Plateau. Our resultant high-resolution images

A comprehensive analysis of contaminant transport in the vadose zone beneath tank SX-109

International Nuclear Information System (INIS)

Ward, A.L.; Gee, G.W.; White, M.D.

1997-02-01

The Vadose Zone Characterization Project is currently investigating the subsurface distribution of gamma-emitting radionuclides in S and SX Waste Management Area (WMA-S-SX) located in the 200 West Area of the US Department of Energy's Hanford Site in southeastern Washington State. Spectral-gamma logging of boreholes has detected elevated 137 Cs concentrations as deep as 38 m, a depth considered excessive based on the assumed geochemistry of 137 Cs in Hanford sediments. Routine groundwater sampling under the Resource Conservation and Recovery Act (RCRA) have also detected elevated levels of site-specific contaminants downgradient of WMA-S-SX. The objective of this report is to explore the processes controlling the migration of 137 Cs, 99 Tc, and NO 3 through the vadose zone of WMA-S-SX, particularly beneath tank SX-109

Grain-Size Dynamics Beneath Mid-Ocean Ridges: Implications for Permeability and Melt Extraction

Science.gov (United States)

Turner, A. J.; Katz, R. F.; Behn, M. D.

2014-12-01

The permeability structure of the sub-ridge mantle plays an important role in how melt is focused and extracted at mid-ocean ridges. Permeability is controlled by porosity and the grain size of the solid mantle matrix, which is in turn controlled by the deformation conditions. To date, models of grain size evolution and mantle deformation have not been coupled to determine the influence of spatial variations in grain-size on the permeability structure at mid-ocean ridges. Rather, current models typically assume a constant grain size for the whole domain [1]. Here, we use 2-D numerical models to evaluate the influence of grain-size variability on the permeability structure beneath a mid-ocean ridge and use these results to speculate on the consequences for melt focusing and extraction. We construct a two-dimensional, single phase model for the steady-state grain size beneath a mid-ocean ridge. The model employs a composite rheology of diffusion creep, dislocation creep, dislocation accommodated grain boundary sliding, and a brittle stress limiter. Grain size is calculated using the "wattmeter" model of Austin and Evans [2]. We investigate the sensitivity of the model to global variations in grain growth exponent, potential temperature, spreading-rate, and grain boundary sliding parameters [3,4]. Our model predicts that permeability varies by two orders of magnitude due to the spatial variability of grain size within the expected melt region of a mid-ocean ridge. The predicted permeability structure suggests grain size may promote focusing of melt towards the ridge axis. Furthermore, the calculated grain size structure should focus melt from a greater depth than models that exclude grain-size variability. Future work will involve evaluating this hypothesis by implementing grain-size dynamics within a two-phase mid-ocean ridge model. The developments of such a model will be discussed. References: [1] R. F. Katz, Journal of Petrology, volume 49, issue 12, page 2099

Neural network analysis for geological interpretation of tomographic images beneath the Japan Islands

Science.gov (United States)

Kuwatani, T.; Toriumi, M.

2009-12-01

Recent advances in methodologies of geophysical observations, such as seismic tomography, seismic reflection method and geomagnetic method, provide us a large amount and a wide variety of data for physical properties of a crust and upper mantle (e.g. Matsubara et al. (2008)). However, it has still been difficult to specify a rock type and its physical conditions, mainly because (1) available data usually have a lot of error and uncertainty, and (2) physical properties of rocks are greatly affected by fluid and microstructures. The objective interpretation and quantitative evaluation for lithology and fluid-related structure require the statistical analyses of integrated geophysical and geological data. Self-Organizing Maps (SOMs) are unsupervised artificial neural networks that map the input space into clusters in a topological form whose organization is related to trends in the input data (Kohonen 2001). SOMs are powerful neural network techniques to classify and interpret multiattribute data sets. Results of SOM classifications can be represented as 2D images, called feature maps which illustrate the complexity and interrelationships among input data sets. Recently, some works have used SOM in order to interpret multidimensional, non-linear, and highly noised geophysical data for purposes of geological prediction (e.g. Klose 2006; Tselentis et al. 2007; Bauer et al. 2008). This paper describes the application of SOM to the 3D velocity structure beneath the whole Japan islands (e.g. Matsubara et al. 2008). From the obtained feature maps, we can specify the lithology and qualitatively evaluate the effect of fluid-related structures. Moreover, re-projection of feature maps onto the 3D velocity structures resulted in detailed images of the structures within the plates. The Pacific plate and the Philippine Sea plate subducting beneath the Eurasian plate can be imaged more clearly than the original P- and S-wave velocity structures. In order to understand more precise

Experimental simulation of magma-carbonate interaction beneath Mt. Vesuvius, Italy

Science.gov (United States)

Jolis, E. M.; Freda, C.; Troll, V. R.; Deegan, F. M.; Blythe, L. S.; McLeod, C. L.; Davidson, J. P.

2013-11-01

We simulated the process of magma-carbonate interaction beneath Mt. Vesuvius in short duration piston-cylinder experiments under controlled magmatic conditions (from 0 to 300 s at 0.5 GPa and 1,200 °C), using a Vesuvius shoshonite composition and upper crustal limestone and dolostone as starting materials. Backscattered electron images and chemical analysis (major and trace elements and Sr isotopes) of sequential experimental products allow us to identify the textural and chemical evolution of carbonated products during the assimilation process. We demonstrate that melt-carbonate interaction can be extremely fast (minutes), and results in dynamic contamination of the host melt with respect to Ca, Mg and 87Sr/86Sr, coupled with intense CO2 vesiculation at the melt-carbonate interface. Binary mixing between carbonate and uncontaminated melt cannot explain the geochemical variations of the experimental charges in full and convection and diffusion likely also operated in the charges. Physical mixing and mingling driven by exsolving volatiles seems to be a key process to promote melt homogenisation. Our results reinforce hypotheses that magma-carbonate interaction is a relevant and ongoing process at Mt. Vesuvius and one that may operate not only on a geological, but on a human timescale.

Seismic velocity structure in the lower crust beneath the seismic belt in the San-in district, Southwest Japan

Science.gov (United States)

Tsuda, H.; Iio, Y.; Shibutani, T.

2017-12-01

In the San-in district in Southwest Japan, a linear distribution of the epicenters of microearthquakes is seen along the coast of the Japan Sea (Fig. 1). The linear distribution is known as the seismic belt in the San-in district. Large earthquakes also occurred in the seismic belt. What localizes the earthquake distribution in the San-in district which is located far from the plate boundary? We thought that the model proposed by Iio et al. (2002, 2004) could answer this question. The model is as follows. Viscosity is low in a part of the lower crust, which is called `weak zone'. Stress and strain are concentrated in the upper crust right above the weak zone, due to concentrated deformation in the weak zone, and thus earthquakes occur there. To verify whether the weak zone exists in the lower crust beneath the seismic belt, we estimated the seismic velocity structure there by travel-time tomography. We used the tomography program, FMTOMO (Rawlinson et al., 2006). For the model space, we set the latitude range of 33°-36°N, the longitude range of 131°-136°E (Fig. 1), and the depth range of 0-81 km. The grid intervals are 0.1°×0.1°×7 km. We used arrival times picked by Japan Meteorological Agency (JMA) for earthquakes that occurred in the study area. In addition, we used arrival times manually picked at stations in and around the San-in district for earthquakes that occurred within the Philippine Sea Slab, because they are not included in the JMA data. Since the seismic waves from those earthquakes to the stations in the San-in district pass through the lower crust beneath the San-in district, we expect that these data can improve the resolution there. We revealed that low velocity anomalies exist in the lower crust beneath the seismic belt (Fig. 1). It is inferred that the region of low velocity anomalies is characterized by low viscosity, since velocities of rocks decrease with temperature and/or water content. Therefore, the results of this study support

Nontarget effects of ivermectin residues on earthworms and springtails dwelling beneath dung of treated cattle in four countries.

Science.gov (United States)

Scheffczyk, Adam; Floate, Kevin D; Blanckenhorn, Wolf U; Düring, Rolf-Alexander; Klockner, Andrea; Lahr, Joost; Lumaret, Jean-Pierre; Salamon, Jörg-Alfred; Tixier, Thomas; Wohde, Manuel; Römbke, Jörg

2016-08-01

The authorization of veterinary medicinal products requires that they be assessed for nontarget effects in the environment. Numerous field studies have assessed these effects on dung organisms. However, few studies have examined effects on soil-dwelling organisms, which might be exposed to veterinary medicinal product residues released during dung degradation. The authors compared the abundance of earthworms and springtails in soil beneath dung from untreated cattle and from cattle treated 0 d, 3 d, 7 d, 14 d, and 28 d previously with ivermectin. Study sites were located in different ecoregions in Switzerland (Continental), The Netherlands (Atlantic), France (Mediterranean), and Canada (Northern Mixed Grassland). Samples were collected using standard methods from 1 mo to 12 mo after pat deposition. Ivermectin concentrations in soil beneath dung pats ranged from 0.02 mg/kg dry weight (3 mo) to typically Earthworms were abundant and species-rich at the Swiss and Dutch sites, less common with fewer species at the French site, and essentially absent at the Canadian site. Diverse but highly variable communities of springtails were present at all sites. Overall, results showed little effect of residues on either earthworms or springtails. The authors recommend that inclusion of soil organisms in field studies to assess the nontarget effects of veterinary medicinal products be required only if earthworms or springtails exhibit sensitivity to the product in laboratory tests. Environ Toxicol Chem 2016;35:1959-1969. © 2015 SETAC. © 2015 SETAC.

Evidence for range contraction of snowshoe hare in Pennsylvania

Science.gov (United States)

Diefenbach, Duane R.; Rathbun, Stephen L.; Vreeland, J.K.; Grove, Deborah; Kanapaux, William J.

2016-01-01

In Pennsylvania, Lepus americanus (Snowshoe Hare) is near the southern limits of its range and at risk of range contraction because of loss of early-successional forest and impacts of climate change. We used hunter-harvest data to investigate changes in the distribution of Snowshoe Hare in Pennsylvania (1983–2011), forest inventory and land-use data to assess changes in amount and distribution of early-successional forest (1988–2011), and occupancy modeling (2004) to identify habitat and climate variables that explain the current distribution of Snowshoe Hare. We determined presence of Snowshoe Hare based on visual sightings, observations of tracks, and DNA analysis of fecal pellets, and used repeated visits to sampling sites and occupancy models to estimate occupancy rates (Ψ). Hunter-harvest data indicated the range of Snowshoe Hare in Pennsylvania contracted towards northwestern and northeastern portions of the state. Based on occupancy modeling, Snowshoe Hare were most likely to occupy early-successional and mixed deciduous-coniferous forest types and areas with colder winter temperatures, which coincided with the distribution of hunter harvests. Among the 4 forest types, we estimated Ψ = 0.52-0.79 and Ψ = 0.10-0.32 where winter temperatures were coldest and warmest, respectively. Total forest loss was Pennsylvania may decline from 0.27 in 2004 to 0.10–0.18 by 2050–2059, depending on the climate model. The range of Snowshoe Hare in Pennsylvania has contracted to regions of Pennsylvania with the coldest winter temperatures and most persistent snowpack, and based on projected climate change, our results suggest further range contraction of Snowshoe Hare in Pennsylvania.

Using helicopter TEM to delineate fresh water and salt water zones in the aquifer beneath the Okavango Delta, Botswana

Science.gov (United States)

Podgorski, Joel E.; Kinzelbach, Wolfgang K. H.; Kgotlhang, Lesego

2017-09-01

The Okavango Delta is a vast wetland wilderness in the middle of the Kalahari Desert of Botswana. It is a largely closed hydrological system with most water leaving the delta by evapotranspiration. In spite of this, the channels and swamps of the delta remain surprisingly low in salinity. To help understand the hydrological processes at work, we reanalyzed a previous inversion of data collected from a helicopter transient electromagnetic (HTEM) survey of the entire delta and performed an inversion of a high resolution dataset recorded during the same survey. Our results show widespread infiltration of fresh water to as much as ∼200 m depth into the regional saline aquifer. Beneath the western delta, freshwater infiltration extends to only about 80 m depth. Hydrological modeling with SEAWAT confirms that this may be due to rebound of the regional saltwater-freshwater interface following the cessation of surface flooding over this part of the delta in the 1880s. Our resistivity models also provide evidence for active and inactive saltwater fingers to as much as ∼100 m beneath islands. These results demonstrate the great extent of freshwater infiltration across the delta and also show that all vegetated areas along the delta's channels and swamps are potential locations for transferring solutes from surface water to an aquifer at depth.

78 FR 45375 - Migratory Bird Hunting; Proposed Frameworks for Early-Season Migratory Bird Hunting Regulations...

Science.gov (United States)

2013-07-26

... heard per route from the Mourning Dove Call-count Survey (CCS), doves seen per route from the CCS, birds... recovery and harvest data. Harvest and hunter participation are estimated from the HIP. The CCS-heard data... management units. Over the long term, trends based on CCS-heard and CCS-seen data were consistent in the CMU...

Hadza hunter-gatherer men do not have more masculine digit ratios (2D:4D).

Science.gov (United States)

Apicella, Coren L; Tobolsky, Victoria A; Marlowe, Frank W; Miller, Kathleen W

2016-02-01

The ratio between the length of the second and the length of the fourth digit (2D:4D) is sexually dimorphic such that males of many species possess a lower ratio than females, particularly in the right hand. Still, men and women often exhibit overlapping 2D:4D ranges and the ratio is highly variable between populations. In order to further explore populational variability, we chose to analyze 2D:4D in the Hadza, a population of hunter-gatherers living in Tanzania. Data were collected separately by two researchers over the course of three years (1998, 2001, 2006) from 152 adult participants (male: n = 76, female: n = 76). Independent samples t-tests were used to explore sex differences, paired samples t-tests were used to explore directional effects within each sex, and linear regression and one-way ANOVA were used to test possible age effects. In none of the years, or pooled (n = 152), did we find evidence that adult men have a lower 2D:4D than adult women. If anything, the data suggest that women in this population have a significantly lower right hand 2D:4D than men (P < 0.001, d = 0.57). In contrast, left hand 2D:4D did not exhibit a sex difference (P = 0.862, d = 0.03). These findings challenge the current view that lower 2D:4D in men is a uniform characteristic of our species. Cross-populational variance in 2D:4D may be related to known patterns of hormonal variation resulting from both genetic and environmental mechanisms, though this relationship merits further investigation. © 2015 Wiley Periodicals, Inc.

Hydrothermal system beneath the crater of Tarumai volcano, Japan : 3-D resistivity structure revealed using audio-magnetotellurics and induction vector

OpenAIRE

Yamaya, Yusuke; Mogi, Toru; Hashimoto, Takeshi; Ichihara, Hiroshi

2009-01-01

Audio-magnetotelluric (AMT) measurements were recorded in the crater area of Tarumai volcano, northeastern Japan. This survey brought the specific structures beneath the lava dome of Tarumai volcano, enabling us to interpret the relationship between the subsurface structure and fumarolic activity in the vicinity of a lava dome. Three-dimensional resistivity modeling was performed to achieve this purpose. The measured induction vectors pointed toward the center of the dome, implying the topogr...

Oxygen Tension Beneath Scleral Lenses of Different Clearances.

Science.gov (United States)

Giasson, Claude J; Morency, Jeanne; Melillo, Marc; Michaud, Langis

2017-04-01

To evaluate the relative partial pressure in oxygen (pO2) at the corneal surface under Boston XO2 scleral lenses (SL) fitted with targeted clearances of 200 and 400 μm (SL200 and SL400). During this prospective study, the right eyes of eight normal subjects were fitted with SL200 and SL400. Clearance, validated after 5 minutes of wear with an optical coherence tomograph, was used with lens thicknesses to calculate transmissibility and estimate pO2. Corneal pO2s were measured with an oxygen electrode after 5 minutes of (1) corneal exposure to calibrating gases with various pO2 or of (2) SL wear. Decays in pO2 were modeled to an exponential. Linear regression between exponent k of these decays and calibrating gas pO2s allowed for the calculation of corneal pO2 under SL. Differences between pO2s beneath SL200 and SL400 were tested with a mixed ANOVA. The estimated transmissibility based on thicknesses and clearances (239.7 ± 34.7; 434.5 ± 33.2 μm) predicted a corneal pO2 of 8.52 ± 0.51 and 6.37 ± 0.28% for SL200 and SL400. These values were close to measured pO2: 9.07 ± 0.86 and 6.19 ± 0.87% (mean ± SEM) (P time, an 18-mm scleral lens fitted with a 400-μm clearance reduces the oxygen tension available to the cornea by 30% compared to a similar lens fitted with a 200-μm clearance after 5 minutes of wear.

Bone transplantation and tissue engineering, part I. Mythology, miracles and fantasy: from Chimera to the Miracle of the Black Leg of Saints Cosmas and Damian and the cock of John Hunter.

Science.gov (United States)

Hernigou, Philippe

2014-12-01

The replacement of diseased organs and tissues by the healthy ones of others has been a unique milestone in modern medicine. However, even though cloning, member transplantation and regenerative therapies with stem cells are available in the twentieth and twenty-first centuries, one should remember that all these techniques were in the imagination more than 2,000 years ago. For centuries, transplantation remained a theme of mythology, miracle or fantasy and was found only in literature and arts. This first paper explains the concept of tissue transplantation from the period when it was relegated to the imagination to the work of the Scottish surgeon and anatomist, John Hunter, who demonstrated the viability of bone allograft.