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Sample records for cerrillos obsidians case

  1. Multivariate analysis in provenance studies: Cerrillos obsidians case, Peru

    International Nuclear Information System (INIS)

    Bustamante, A.; Delgado, M.; Latini, R. M.; Bellido, A. V. B.

    2007-01-01

    We present the preliminary results of a provenance study of obsidians samples from Cerrillos (ca. 800-100 b.c.) using Moessbauer Spectroscopy. The Cerrillos archaeological site, located in the Upper Ica Valley, Peru, is the only Paracas ceremonial center excavated so far. The archaeological data collected suggest the existence of a complex social and economic organization on the south coast of Peru. Provenance research of obsidian provides valuable information about the selection of lithic resources by our ancestors and eventually about the existence of communication routes and exchange networks. We characterized 18 obsidian artifacts samples by Moessbauer spectroscopy from Cerrillos. The spectra, recorded at room temperature using different velocities, are mainly composed of broad asymmetric doublets due to the superposition of at least two quadrupole doublets corresponding to Fe 2+ in two different sites (species A and B), one weak Fe 3+ doublet (specie C) and magnetic components associated to the presence of small particles of magnetite. Multivariate statistical analysis of the Moessbauer data (hyperfine parameters) allows to defined two main groups of obsidians, reflecting different geographical origins.

  2. Multivariate analysis in provenance studies: Cerrillos obsidians case, Peru

    Science.gov (United States)

    Bustamante, A.; Delgado, M.; Latini, R. M.; Bellido, A. V. B.

    2007-02-01

    We present the preliminary results of a provenance study of obsidians samples from Cerrillos (ca. 800 100 b.c.) using Mössbauer Spectroscopy. The Cerrillos archaeological site, located in the Upper Ica Valley, Peru, is the only Paracas ceremonial center excavated so far. The archaeological data collected suggest the existence of a complex social and economic organization on the south coast of Peru. Provenance research of obsidian provides valuable information about the selection of lithic resources by our ancestors and eventually about the existence of communication routes and exchange networks. We characterized 18 obsidian artifacts samples by Mössbauer spectroscopy from Cerrillos. The spectra, recorded at room temperature using different velocities, are mainly composed of broad asymmetric doublets due to the superposition of at least two quadrupole doublets corresponding to Fe2+ in two different sites (species A and B), one weak Fe3+ doublet (specie C) and magnetic components associated to the presence of small particles of magnetite. Multivariate statistical analysis of the Mössbauer data (hyperfine parameters) allows to defined two main groups of obsidians, reflecting different geographical origins.

  3. Characterization by Moessbauer Spectroscopy and Electron Paramagnetic Resonance of Peruvian Obsidians for Provenance Studies: A Preliminary Study

    International Nuclear Information System (INIS)

    Bustamante, A.; Montoya, J.; Delgado, M.; Scorzelli, R. B.; Rossi, A. M.; Poupeau, G.

    2003-01-01

    The identification of geological sources of obsidians collected in archaeological sites provides important information about circulation routes and sociocultural relationships during prehistoric periods. This paper presents the preliminary results obtained by MS and EPR on geological obsidians from Ayacucho and Arequipa, in Peru and on archaeological obsidian artifacts from Cerrillos, an early Paracas site of the upper Ica valley, south of Lima (Peru).

  4. Sedimentation survey of Lago Cerrillos, Ponce, Puerto Rico, April-May 2008

    Science.gov (United States)

    Soler-López, Luis R.

    2011-01-01

    Lago Cerrillos dam, located in the municipality of Ponce in southern Puerto Rico, was constructed in 1991 as part of the multipurpose Rio Portugues and Bucana Project. This project provides flood protection, water supply, and recreation facilities for the municipio of Ponce. The reservoir had an original storage capacity of 38.03 million cubic meters at maximum conservation pool elevation of 174.65 meters above mean sea level and a drainage area of 45.32 square kilometers. Sedimentation in Lago Cerrillos reservoir has reduced the storage capacity from 38.03 million cubic meters in 1991 to 37.26 million cubic meters in 2008, which represents a total storage loss of about 2 percent. During July 29 to August 23, 2002, 8,492 cubic meters of sediment were removed from the Rio Cerrillos mouth of the reservoir. Taking into account this removed material, the total water-storage loss as of 2008 is 778,492 cubic meters, and the long-term annual water-storage capacity loss rate is about 45,794 cubic meters per year or about 0.12 percent per year. The Lago Cerrillos net sediment-contributing drainage area has an average sediment yield of about 1,069 cubic meters per square kilometer per year. Sediment accumulation in Lago Cerrillos is not uniformly distributed and averages about 3 meters in thickness. This represents a sediment deposition rate of about 18 centimeters per year. On the basis of the 2008 reservoir storage capacity of 37.26 million cubic meters per year and a long-term sedimentation rate of 45,794 cubic meters per year, Lago Cerrillos is estimated to have a useful life of about 814 years or until the year 2822.

  5. New Evidences for Early Paracas Textiles and Ceramics at Cerrillos, Ica Valley, Perú

    OpenAIRE

    Splitstoser, Jeffrey; Wallace, Dwight D.; Delgado, Mercedes

    2012-01-01

    Cerrillos is an Early to Middle Paracas civic-ceremonial site located in the upper Ica Valley of Perú. The site is known for its finely plastered adobe architecture, beautifully decorated ceramics, and complex textiles, many of which are decorated with camelid hair. Cerrillos was located in a strategically important place where the mountains meet the coastal desert and the Ica River bends south, a likely intersection in a road system that connected Cerrillos to contemporary sites in the Parac...

  6. Analisis Teknologi Artefak Obsidian Danau Bandung Purba

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    Anton Ferdianto

    2012-06-01

    Full Text Available Abstract. Stone tool's was one of a kind that prehistory man use and made, where is purpose or un purpose to help their daily life's. There's lot of stone material that man could use to make stone tool and one of them is Obsidian. An archaeological survei had been conduct in Bandung Basin and Obsidian artifact was found there. Analysis from Obsidian artifact that found in several site in Bandung basin in this case classification and typology was throughout in these research, and conclude that the knapping stone technology in Bandung Basin area was quite high. Keywords: alat batu, danau bandung, obsidian

  7. Obsidian dating prospects

    International Nuclear Information System (INIS)

    Ambrose, W.

    1997-01-01

    Full text: Developments in the nuclear industry have shown that some of the problems related to the glassification of waste for long term storage are centred on the rate of glass weathering in various repositories. Long term weathering of artificial glasses is paralleled by the archaeological problem of determining hydration rates in obsidian artefacts as a means of dating their manufacture. Figures available for sites in Papua New Guinea indicate that the weathering rate is sufficiently fast to render conventional hydration measurement completely unreliable. This follows from the range of calculated surface reduction rates which range between .0002μ to .004μ per year depending on the site's location and the obsidian source. Hydration rates for key Papua New Guinea obsidians have been determined from long term experimental laboratory exposure and these are used to evaluate the age of obsidians from selected archaeological sites. By adopting a strategy of measuring hydration in concealed fissures both the weathering rate and the dating of the Papua New Guinea obsidians have been successfully achieved. The dissolution rates of natural obsidians could be useful in considering weathering rates for artificial glasses. An improved system for calculating the annual effective hydration temperature is presented which gives a better control of micro-environmental temperature in its crucial rate determining role. The combined result of these developments gives obsidian hydration dating an enhanced capacity to be a useful and independent dating system

  8. Preliminary Study on the Provenance Interpretation of Obsidian Artifacts using Neutron Activation Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Mi Eun; Jwa, Yong Joo [Gyeongsang National University, Jinju (Korea, Republic of); Sun, Gwang Min; Baek, Ha Ni; Moon, Jong Hwa; Chung, Yong Sam [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    In the case that the obsidian artifacts are treated as a prehistoric cultural property, we cannot analyze them using destructive analytical methods. In this study, we compared geochemical data obtained by NAA with that by the other method, and examined the applicability of the NAA method to interpret the provenance of the obsidian artifacts. Both the NAA and the LA-ICP-MS data show a general similarity in elemental variation. In particular, it is possible to distinguish Baekdusan obsidians from Kyushu obsidians. This kind of contrast between the Baekdusan and the Kyushu obsidians would reflect the different magma composition at the different tectonic and geologic settings. In general the geochemical composition of obsidian is closely related to the accompanied volcanic rocks. For more detailed estimation of obsidian provenance, we should use the geochemical compositions of obsidians as well as volcanic rocks.

  9. Exchange networks from close-up: The case of Lipari obsidian

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    Andrea Vianello

    2016-09-01

    Full Text Available A systematic study on obsidian tools in Calabria and Sicily carried out by the authors have revealed the uniqueness in the patterns of production, exchange and consumption of Lipari obsidian. The study has concentrated on the Middle Neolithic primarily, with other Neolithic and Bronze Age contexts recognised at a later stage in the research since many contexts, especially in Sicily, have been excavated by pioneering archaeologists, some over a century ago, or were mislabelled. The chronology is Early Neolithic to Early Bronze Age, with very few materials dating Middle Bronze Age. A review of chronological contexts is in progress, which spans from the 6th millennium BC to the end of the 2nd millennium BC. The typology of obsidian tools is very homogenous, the vast majority of used tools are small blades, bladelets and sharp flakes; there is negligible variance across time; and Lipari obsidian is preferred over other sources. The patterns of the exchanges are also unique, revealing two major types of redistribution of obsidian, one particularly intriguing because it is quite organized with a single source in Lipari, prominent and reminiscent for its stability and reach of Bronze Age redistribution dynamics associated with hierarchical societies. We present here some observations on patterns substantiated by the archaeological record, and consider possible scenarios that can explain them. This work provides an update on progressing research and reveals aspects that will need further investigation, focusing on the patterns identified so far and possible explanations. More work is certainly needed to produce a working model, but the unusual patterns deserve some attention on their own, unencumbered by an overarching explanatory model. In particular, we want to assess the Neolithic redistribution pattern suggestive as typical of hierarchical polities, and contextualize it to the specific situation of Neolithic Lipari.

  10. Tikal obsidian: sources and typology

    Energy Technology Data Exchange (ETDEWEB)

    Moholy-Nagy, H.; Asaro, F.; Stross, F.H.

    1984-01-01

    The obsidian industry of Classic period Tikal, Guatemala, is discussed with regard to geological source determinations and behavioral typology. The potential of these two approaches for cultural reconstruction is greatly extended when they can supplement each other. Recent source determinations of obsidian artifacts from Tikal indicate (1) a behavioral link between locally-produced prismatic blades of Highland Guatemalan stone and ceremonial incised obsidians and eccentrics, and (2) a Central Mexican origin for a seemingly large portion of Tikal's obsidian projectile points and knives. 25 references, 3 figures, 5 tables.

  11. The obsidian mirror The obsidian mirror

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    Maria do Socorro Reis Amorin

    2008-04-01

    Full Text Available The author James Norman is an American who has always lived in Mexico during the summer. He seems to love Mexican - Indian traditions and he is well acquainted with the pre-historic culture as it is shown in his book: "The Obsidian Mirror". "The Obsidian Mirror" is a mysterious story about an archeologist: Quigley that lives in a small village in Mexico-San Marcos. He is searching for antiques that belong to some tribes of pre-historic Indians in order to find out their mysteries. Quigley becomes so engaged in his work that his mind has reached a stage that is impossible to separate between Quigley the archeologist, and Quigley as an ancient Indian. The culture, the myth, the sensation of Omen - characteristics of the Indians are within himself. As a result, Quigley acts sometimes as a real Indian. The author James Norman is an American who has always lived in Mexico during the summer. He seems to love Mexican - Indian traditions and he is well acquainted with the pre-historic culture as it is shown in his book: "The Obsidian Mirror". "The Obsidian Mirror" is a mysterious story about an archeologist: Quigley that lives in a small village in Mexico-San Marcos. He is searching for antiques that belong to some tribes of pre-historic Indians in order to find out their mysteries. Quigley becomes so engaged in his work that his mind has reached a stage that is impossible to separate between Quigley the archeologist, and Quigley as an ancient Indian. The culture, the myth, the sensation of Omen - characteristics of the Indians are within himself. As a result, Quigley acts sometimes as a real Indian.

  12. Obsidians from the Kerkennah Islands (eastern Tunisia) and the PIXE elemental compositions of the Mediterranean peralkaline obsidians

    International Nuclear Information System (INIS)

    Le Bourdonnec, François-Xavier; Poupeau, Gérard; Boussofara, Ridha

    2015-01-01

    The provenance of 37 obsidians from the Kerkennah Islands (central Mediterranean Sea) was determined by PIXE. It is shown that they came from the two main obsidian sources, Balata dei Turchi and Lago di Venere, of the Pantelleria Island. A comparison of the PIXE elemental composition of geological vs. archaeological obsidians of central and western Mediterranean shows that their sources present elemental compositions homogeneous enough to make possible sourcing studies. However, a comparison between the distributions of geological and archaeological obsidians chemistry shows that the PIXE source qualifications do not cover yet the whole of their internal variations

  13. Obsidians from the Kerkennah Islands (eastern Tunisia) and the PIXE elemental compositions of the Mediterranean peralkaline obsidians

    Energy Technology Data Exchange (ETDEWEB)

    Le Bourdonnec, François-Xavier, E-mail: Francois-Xavier.Le-Bourdonnec@u-bordeaux-montaigne.fr [Institut de Recherche sur les Archéomatériaux (IRAMAT), Centre de Recherche en Physique Appliquée à l’Archéologie (CRP2A), UMR 5060, CNRS-Université Bordeaux Montaigne, Maison de l’Archéologie, Esplanade des Antilles, 33607 Pessac Cédex (France); Poupeau, Gérard [Institut de Recherche sur les Archéomatériaux (IRAMAT), Centre de Recherche en Physique Appliquée à l’Archéologie (CRP2A), UMR 5060, CNRS-Université Bordeaux Montaigne, Maison de l’Archéologie, Esplanade des Antilles, 33607 Pessac Cédex (France); UMR 7194 CNRS et Département de Préhistoire du Muséum National d’Histoire Naturelle, Place du Trocadéro, 75016 Paris (France); Boussofara, Ridha, E-mail: ridha57@yahoo.fr [The National Heritage Institute, 4 Place du Château, 1008 Tunis (Tunisia); and others

    2015-09-01

    The provenance of 37 obsidians from the Kerkennah Islands (central Mediterranean Sea) was determined by PIXE. It is shown that they came from the two main obsidian sources, Balata dei Turchi and Lago di Venere, of the Pantelleria Island. A comparison of the PIXE elemental composition of geological vs. archaeological obsidians of central and western Mediterranean shows that their sources present elemental compositions homogeneous enough to make possible sourcing studies. However, a comparison between the distributions of geological and archaeological obsidians chemistry shows that the PIXE source qualifications do not cover yet the whole of their internal variations.

  14. El proyecto "Ciudad del Viento", Portal Bicentenario, Cerrillos: fecundidad de una idea modelo de diseño urbano sustentable

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    Rubén González Aguayo

    2010-06-01

    Full Text Available A propósito de la oportunidad de reconstrucción del país, post terremoto 2010, y de la evaluación del proyecto ciudad parque, se analiza la propuesta ganadora del Primer Premio del Concurso Internacional de Ideas Portal Bicentenario, “Ciudad del Viento”, emplazada en el ex Aeródromo de Cerrillos en Santiago de Chile, en cuanto modelo de urbanización sustentable. /The reconstruction after de 8.8 earthquake in Chile is an opportunity to review the winner project of the contest "Ciudad Portal Bicentenario", transformation of Cerrillos Airport into a new sustainable city.

  15. Obsidian hydration dates glacial loading?

    Science.gov (United States)

    Friedman, I; Pierce, K L; Obradovich, J D; Long, W D

    1973-05-18

    Three different groups of hydration rinds have been measured on thin sections of obsidian from Obsidian Cliff, Yellowstone National Park, Wyoming. The average thickness of the thickest (oldest) group of hydration rinds is 16.3 micrometers and can be related to the original emplacement of the flow 176,000 years ago (potassium-argon age). In addition to these original surfaces, most thin sections show cracks and surfaces which have average hydration rind thicknesses of 14.5 and 7.9 micrometers. These later two hydration rinds compare closely in thickness with those on obsidian pebbles in the Bull Lake and Pinedale terminal moraines in the West Yellowstone Basin, which are 14 to 15 and 7 to 8 micrometers thick, respectively. The later cracks are thought to have been formed by glacial loading during the Bull Lake and Pinedale glaciations, when an estimated 800 meters of ice covered the Obsidian Cliff flow.

  16. Budaya Obsidian di Tepian Danau Bandung Purba

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    Lutfi Yondri

    2016-07-01

    Abstracts,  This paper tries to elaborate the result about study of obsidian culture, which had been found by many spread location over the shore of the aancient lake of Bandung. Can be estimate from the locations, which have obsidian artifact in the prehistoric human being possibility in the shore, had been exploited or use the same resource obsidian in range of thousands of year ago. Obsidian culture and its artifacts still become as one debate among the expert, regarding its chronology, and also about human behind who supported its culture. With the existence of new finding data from Pawon Cave, the obsidian culture tried to discuss, so that some the problems can be given the clarification such as about its chronology and also its society behind. Keywords: artifact, distribution, chronology, culture, and society

  17. Obsidian sources characterized by neutron-activation analysis.

    Science.gov (United States)

    Gordus, A A; Wright, G A; Griffin, J B

    1968-07-26

    Concentrations of elements such as manganese, scandium, lanthanum, rubidium, samarium, barium, and zirconium in obsidian samples from different flows show ranges of 1000 percent or more, whereas the variation in element content in obsidian samples from a single flow appears to be less than 40 percent. Neutron-activation analysis of these elements, as well as of sodium and iron, provides a means of identifying the geologic source of an archeological artifact of obsidian.

  18. Chemistry of the subalkalic silicic obsidians

    Science.gov (United States)

    MacDonald, Ray; Smith, Robert L.; Thomas, John E.

    1992-01-01

    Nonhydrated obsidians are quenched magmatic liquids that record in their chemical compositions details of the tectonic environment of formation and of the differentiation mechanisms that affected their subsequent evolution. This study attempts to analyze, in terms of geologic processes, the compositional variations in the subalkalic silicic obsidians (Si02≥70 percent by weight, molecular (Na2O+K20)>Al2O3). New major- and trace-element determinations of 241 samples and a compilation of 130 published major-element analyses are reported and interpreted. Obsidians from five different tectonic settings are recognized: (1) primitive island arcs, (2) mature island arcs, (3) continental margins, (4) continental interiors, and (5) oceanic extensional zones. Tectonomagmatic discrimination between these groups is successfully made on Nb-Ta, Nb-FeOt and Th-Hf-Ta plots, and compositional ranges and averages for each group are presented. The chemical differences between groups are related to the type of crust in which magmas were generated. With increasingly sialic (continental type) crust, the obsidians show overall enrichment in F, Be, Li, Mo, Nb, Rb, Sn, Ta, U, W, Zn, and the rare-earth elements, and depletion in Mg, Ca, Ba, Co, Sc, Sr, and Zr. They become more potassic, have higher Fe/Mg and F/Cl ratios, and lower Zr/Hf, Nb/Ta, and Th/U ratios. Higher values of total rare-earth elements are accompanied by light rare-earth-element enrichment and pronounced negative Eu anomalies. An attempt is made to link obsidian chemistry to genetic mechanlism. Two broad groups of rocks are distinguished: one generated where crystal-liquid processes dominated (CLPD types), which are the products of crustal anatexis, possibly under conditions of low halogen fugacity, ± crystal fractionation ± magma mixing; and a second group represented by rocks formed in the upper parts of large magma chambers by interplays of crystal fractionation, volatile transfer, magma mixing, and possibly various

  19. Shirataki obsidian exploitation and circulation in prehistoric northern Japan

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    Miyuki Yakushige

    2014-03-01

    Full Text Available Presently, the total number of archaeological obsidian sources in Japan is more than 80, and among them, 21 are in Hokkaido, northern part of the Japanese archipelago (Izuho and Sato 2007. Obsidian was the dominant of lithic raw material in the Upper Paleolithic Hokkaido (35-10 ka cal BP. Out of 21 archaeological obsidian sources in Hokkaido, 4 sources: Shirataki, Oketo, Tokachi, and Akaigawa are the major obsidian sources and the others are minor sources. Shirataki is one of the largest obsidian sources in Northeast Asia and it is well known that Shirataki obsidian was transported outside Hokkaido to Sakhalin and the Paleo-Honshu Island from the Late Upper Paleolithic period.We compiled data of obsidian source analyses conducted to artefacts from Paleolithic sites in Hokkaido, and it became clear that the ratio of Shirataki obsidian in all analyzed materials is more than half (Sato and Yakushige in press.We examined how far Shirataki obsidian was transported in each period: the Early Upper Paleolithic (35-25 ka cal BP and the Late Upper Paleolithic (25-10 ka cal BP. The Late Upper Paleolithic is divided into three stage, the early Early Microblade Industry (Stage 1: 25-21 ka cal BP, the late Early Microblade Industry (Stage 2: 19-16 ka cal BP, and the Late Microblade Industry (Stage 3: 16-10 ka cal BP. As a result, it is revealed that the distribution areas of Shirataki obsidian did not expand gradually over time, but are different in different lithic industries. In the background of this situation lay the difference of ecological adaptation strategies adopted by the prehistoric people of the time and their movement behavioral strategies.

  20. Magnetic studies of archaeological obsidian: Variability of eruptive conditions within obsidian flows is key to high-resolution artifact sourcing (Invited)

    Science.gov (United States)

    Feinberg, J. M.; Frahm, E.; Muth, M.

    2013-12-01

    Previous studies have endeavored to use petrophysical traits of obsidian, particularly its magnetic properties, as an alternative to conventional geochemical sourcing, one of the greatest successes in archaeological science. Magnetic approaches, however, have not seen widespread application due to their mixed success. In a time when geochemical analyses can be conducted non-destructively, in the field, and in a minute or two, magnetic measurements of obsidian must offer novel archaeological insights to be worthwhile, not merely act as a less successful version of geochemistry. To this end, we report the findings of a large-scale study of obsidian magnetism, which includes 912 geological obsidian specimens and 97 artifacts measured for six simple magnetic parameters. Based on these results, we propose, rather than using magnetic properties to source artifacts to a particular obsidian flow (inter-flow sourcing), these properties are best used to differentiate quarrying sites within an individual flow (intra-flow sourcing). The magnetic properties within an individual flow are highly variable, due to the fact that a single flow experiences a wide array of cooling rates, absolute temperatures, viscosities, deformation, and oxidation. These conditions affect the concentrations, compositions, size distributions, shapes, and spatial arrangements of magnetic grains within an obsidian specimen and, thus, its intrinsic magnetic properties. This variability decreases dramatically at spatial scales of individual outcrops, and decreases even further at scales of hand samples. Thus, magnetic data appear to shift the scale of obsidian sourcing from flows to quarries and, in turn, enable new insights into raw-material procurement strategies, group mobility, lithic technology, and the organization of space and production. From a geologic perspective, the magnetic variability of obsidian can be broadly interpreted within the context of the igneous processes that were active during

  1. The obsidian sources of Northland, New Zealand

    International Nuclear Information System (INIS)

    Moore, P.R.

    2012-01-01

    Four sources of obsidian have previously been recognized in Northland, but more recent field observations and new chemical analyses indicate there are three (Pungaere, Otoroa and Huruiki). Obsidian from these sources can be readily distinguished on the basis of visual characteristics and chemical attributes. The Pungaere obsidian, which is peralkaline in composition, is characterized chemically by unusually high Zr, high Rb, and very low Ba and Sr concentrations. Only two of the sources (Pungaere and Huruiki) appear to have been exploited by pre-European Maori. Available analyses of artefact assemblages suggest that Pungaere obsidian was widely distributed throughout Northland from the fourteenth century, but use of the Huruiki source may have been more limited. (author). 36 refs., 7 figs., 3 tabs.

  2. LA-ICP-MS zircon U-Pb geochronology to constrain the age of post-Neocomian continental deposits of the Cerrillos Formation, Atacama Region , northern Chile: tectonic and metallogenic implications Geocronología U-Pb en circón por LA-ICP-MS para circunscribir la edad de depósitos continentales post-neocomianos de la Formacion Cerrillos, Región de Atacama, norte de Chile: implicancias tectónicas y metalogénicas

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    Víctor Maksaev

    2009-07-01

    Full Text Available New U-Pb zircon dating of volcamc intercalations in the lower conglomeratic part of the Cerrillos Formation shows that its deposition extended in time at least from 110.7±1.7 to 99.7±1.6 Ma. The significantly younger U-Pb zircon age of 69.5±1.0 Ma obtained for the upper volcamc part of the Cerrillos Formation suggests recurrence of volcanism in the Late Cretaceous instead of continual volcanic activity. A minimum late Maastrichtian age for the Cerrillos Formation and its initial deformation was determined by the U-Pb zircon age range from 66.9±1.0 to 65.2±1.0 Ma for the lower part of the unconformably overlying Hornitos Formation. The new U-Pb data for the Cerrillos and Hornitos formations poses questions about the Campanian-Maastrichtian age range currently ascribed to the latter. The lower part of the Cerrillos Formation represents a major change in the sedimentary regime from previous marine carbonate sedimentation in a back-arc basin until the late Aptian to subsequent coarse alluvial sedimentation and volcanism since the early Albian. The lower part of the Cerrillos Formation is interpreted as the development of coalescent alluvial fans thinning inland, accompanied by volcanism. These developed as the result of transpressive deformation and uplift of the area of the current Coastal Cordillera by late Aptian, leading to subsequent active erosion and sedimentation inland, along with the eastward shift of the magmatic foci in the Región . Amineralizing period of Cu-Au porphyries overlaps in time with the deposition of the Cerrillos Formation in northern Chile; marking also a significant change in the metallogeny of the Andes of northern Chile.Nuevas dataciones U-Pb obtenidas para intercalaciones volcánicas en la parte inferior conglomerádica de la Formacion Cerrillos muestran que su depositacion se extendió en el tiempo al menos desde 110,7±1,7 hasta 99,7±1,6 Ma. La edad U-Pb significativamente más joven de 69,5±1,0 Ma obtenida

  3. Fission tracks dating for obsidian

    International Nuclear Information System (INIS)

    Picon, C.

    1991-01-01

    Obsidian from South America are dated by fission tracks methods. Samples are irradiated in a nuclear reactor with a flux of 10 15 n/cm 2 . Results, corrected by 'Plateau' methods, are the following: obsidian from Bolivia: 4.14 x 10 6 yr., Ecuador: 8.79 x 10 5 yr., Colombia: 3.52 x 10 6 yr., Peru: 6.55 x 10 6 yr., Chile: 1.13 x 10 6 yr. (MMZ). 5 refs., 3 tabs

  4. OLDAPS - obsidian least destructive analysis provenancing system: an application study

    International Nuclear Information System (INIS)

    Eder, F.

    2013-01-01

    The natural volcanic glass obsidian is one of the classical objects of archaeometric analyses. Obsidian is generally described as a relatively homogeneous material and although the number of applicable geological sources is limited, numerous obsidian finds have been found all over the world far away from any natural outcrop. Reliable provenancing by means of the highly specific chemical composition, the 'chemical fingerprint', can provide information about trading routes, extension of territory, long-distance contacts and the mobility of prehistoric people. Several museum collections contain large numbers of unidentified obsidian finds. Therefore, a novel scientific approach for provenancing obsidian artefacts found in archaeological contexts is demanded. The establishment of the Obsidian Least Destructive Analysis Provenancing System (OLDAPS) contributes to both conservation and prehistoric research by ensuring a minimum of destruction to gain a maximum of information. Obsidian samples of seven archaeologically relevant geological obsidian sources in Central and Southern Europe were characterized by the application of three different methods: Neutron Activation Analysis (NAA) Ion Beam Analysis (IBA) comprising of Particle Induced X-ray Emission (PIXE) and Particle Induced Gamma-ray Emission (PIGE) Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) The reproducibility and accuracy of analytical data is demonstrated by the excellent agreement between determined analytical results and certified values of glassy reference material BAM-S005B. The combination of methods shows a maximum element spectrum composed of 42 elements and reveals the most characteristic -key elements-, in particular Ti, Co, As, Rb, Ba, Eu and U, by which all seven obsidian sources are cleary discriminable. OLDAPS developed the following analytical strategy to provenance archaeological obsidian, which most likely stem from Central or Southern Europe: The application

  5. Obsidian provenance research in the Americas.

    Science.gov (United States)

    Glascock, Michael D

    2002-08-01

    The characterization of archaeological materials to support provenance research has grown rapidly over the past few decades. Volcanic obsidian has several unique properties that make it the ideal archaeological material for studying prehistoric trade and exchange. This Account describes our laboratory's development of a systematic methodology for the characterization of obsidian sources and artifacts from Mesoamerica and other regions of North and South America in support of archaeological research.

  6. Is Obsidian Hydration Dating Affected by Relative Humidity?

    Science.gov (United States)

    Friedman, I.; Trembour, F.W.; Smith, G.I.; Smith, F.L.

    1994-01-01

    Experiments carried out under temperatures and relative humidities that approximate ambient conditions show that the rate of hydration of obsidian is a function of the relative humidity, as well as of previously established variables of temperature and obsidian chemical composition. Measurements of the relative humidity of soil at 25 sites and at depths of between 0.01 and 2 m below ground show that in most soil environments, at depths below about 0.25 m, the relative humidity is constant at 100%. We have found that the thickness of the hydrated layer developed on obsidian outcrops exposed to the sun and to relative humidities of 30-90% is similar to that formed on other portions of the outcrop that were shielded from the sun and exposed to a relative humidity of approximately 100%. Surface samples of obsidian exposed to solar heating should hydrate more rapidly than samples buried in the ground. However, the effect of the lower mean relative humidity experiences by surface samples tends to compensate for the elevated temperature, which may explain why obsidian hydration ages of surface samples usually approximate those derived from buried samples.

  7. The origin and exchange of obsidian from Vinča-Belo Brdo

    Directory of Open Access Journals (Sweden)

    Tripković Boban

    2008-01-01

    Full Text Available Since the time of the revolutionary characterization of obsidian in the 1960's only a small number of artefacts from the Serbian sites have been analyzed, of which at least seven samples come from the site of Vinča. These results showed that obsidian was coming from Carpathian sources, disproving old romantic ideas of the existence of local obsidian sources in the central Balkans. These results allowed for the development of ideas about exchange networks of interregional importance during the Late Neolithic in which obsidian was an integral component. In this paper we will be discussing the results of the characterization of 60 obsidian samples, representing ca. 4% of the entire obsidian assemblage from the site. The samples were taken from the whole Neolithic sequence at Vinča selecting macroscopically different obsidian types.

  8. The paredon, Mexico, obsidian source and early formative exchange.

    Science.gov (United States)

    Charlton, T H; Grove, D C; Hopke, P K

    1978-09-01

    In 1975, archeological surface surveys of trade routes located again a pre-Hispanic obsidian source in central Mexico first reported in 1902. Initial trace element studies of the Paredón source through an analysis by neutron activation have been compared with similar studies of the obsidian found at Chalcatzingo 150 kilometers from the source. These comparisons indicate that obsidian from Paredón, rather than Otumba, was of primary importance during the Early Formative in central Mexico.

  9. A possible bedrock source for obsidian found in archeological sites in northwestern alaska.

    Science.gov (United States)

    Patton, W W; Miller, T P

    1970-08-21

    Recently discovered deposits of obsidian in the Koyukuk valley may be the long-sought-for source of obsidian found in archeological sites in northwestern Alaska. Obsidian from these deposits compares favorably in physical characteristics and sodium-manganese ratio with the archeological obsidian, and there is evidence that the deposits have been "mined" in the past.

  10. The Challenge of Characterising Large Assemblages of Exotic Materials: a case study of the obsidian from Domuztepe, SE Turkey

    Directory of Open Access Journals (Sweden)

    Elizabeth Healey

    2009-09-01

    Full Text Available Obsidian artefacts from Domuztepe (a large late Neolithic site in the Kahramanmaraş plain in south-east Turkey belonging to the Halaf culture and dated to c. 6000-5500 cal. BC account for about 18%, or some 10,000 artefacts, of the chipped stone assemblage. Obsidian is one of the few non-local materials at Domuztepe and as well as being used to make tools it is also used to make items of jewellery, mirrors, bowls and axe-like objects. We know from the geochemical analysis of a relatively small number of artefacts that the obsidian was imported from eight different and widely separated sources in Central, NE and SE Anatolia. These sources are between 200 and 900km distant from Domuztepe. All these factors suggest that obsidian was valued not only as a raw material for tool manufacture but also as a material from which to make luxury items. As an exotic material it is also likely to have a key role in forging and maintaining social and economic relationships, both within the site and more widely. Understanding of the origins of the obsidians and the form in which they were obtained, worked and used, context by context, is key to this. However, difficulties arise with provenancing such a large assemblage, not least because conventional geo-chemical methods are unfeasibly expensive. This article documents the approaches we have developed to overcome this problem.

  11. Obsidian hydration profile measurements using a nuclear reaction technique

    Science.gov (United States)

    Lee, R.R.; Leich, D.A.; Tombrello, T.A.; Ericson, J.E.; Friedman, I.

    1974-01-01

    AMBIENT water diffuses into the exposed surfaces of obsidian, forming a hydration layer which increases in thickness with time to a maximum depth of 20-40 ??m (ref. 1), this layer being the basic foundation of obsidian dating2,3. ?? 1974 Nature Publishing Group.

  12. A comparison of obsidian and surgical steel scalpel wound healing in rats.

    Science.gov (United States)

    Disa, J J; Vossoughi, J; Goldberg, N H

    1993-10-01

    There are several anecdotal clinical articles claiming wound healing and scar superiority using obsidian (volcanic glass) scalpels. In order to determine if skin incisions made with obsidian were superior to those made with standard surgical steel, wound tensile strength, scar width, and histology were assessed in 40 adult male Sprague-Dawley rats. Each rat received two parallel 8-cm dorsal skin incisions, one with an obsidian scalpel and the other with a surgical steel scalpel (no. 15 blade). Data were analyzed by ANOVA. Tensile strength of the two wound types was not different at 7, 14, 21, and 42 days. Scar width, however, was significantly less in the obsidian wounds at 7, 10, and 14 days (p obsidian wounds contained fewer inflammatory cells and less granulation tissue at 7 days.

  13. Analysis of obsidian from moho cay, belize: new evidence on classic maya trade routes.

    Science.gov (United States)

    Healy, P F; McKillop, H I; Walsh, B

    1984-07-27

    Trace element analysis of obsidian artifacts from Moho Cay, Belize, reveals that the obsidian derives primarily from the El Chayal outcrop in highland Guatemala and not from the Ixtepeque source. This is contrary to the widely accepted obsidian trade route model for Classic Maya civilization and suggests that Classic Maya obsidian trade was a more complex economic phenomenon than has been recognized.

  14. OLDAPS: Obsidian Least Destructive Analysis Provenancing System

    Energy Technology Data Exchange (ETDEWEB)

    Eder, F.M.; Sterba, J.H.; Bichler, M. [Atominstitut, Vienna University of Technology, Vienna (Austria); Neelmeijer, C.; Merchel, S. [Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden (Germany); Pearce, N.J.G. [Institute of Geography and Earth Sciences, Aberystwyth University, Wales (United Kingdom)

    2013-07-01

    Full text: The natural volcanic glass obsidian is one of the classical objects of archaeometric analyses. Reliable provenancing by means of the highly specific chemical composition, the 'chemical fingerprint', can provide information about trading routes, extension of territory, long-distance contacts and the mobility of prehistoric people. Since the pioneer work of Cann and Renfrew in 1964 [1] various analytical methods have been employed on obsidian samples in order to locate their provenance. The existing data already offers important knowledge about long-distance interactions between prehistoric human populations. However, most applied techniques just show a small part of the element spectrum. Latest studies showed that published results gained by different analytical methods are not consistent due to systematic errors [2-3]. Therefore, the application of three complementary analytical techniques on the same set of raw material samples allows both a better characterization of obsidian sources and a comparison and validation of analytical results. The aim of this multi-methodical approach is to apply in particular: 1) lon Beam Analysis (IBA) comprising of Particle Induced X-ray Emission (PIXE) and Particle Induced Gamma-ray Emission (PIGE), 2) Instrumental Neutron Activation Analysis (INAA), 3) Laser Ablation-lnductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS), to detect a maximum element spectrum and to compare element concentrations determined with at least two analytical techniques. This approach should check the accuracy and reliability of analytical results and should show a maximum of compositional differences between European obsidian sources to reveal the most characteristic 'chemical fingerprint' composed of more than 40 elements. These investigations are part of a new multi-methodical analytical database called the 'Obsidian Least Destructive Analysis Provenancing System' (OLDAPS). This novel scientific approach for

  15. Obsidian dating by fission track method

    International Nuclear Information System (INIS)

    Araya, A.M.O.

    1990-12-01

    The fission track method was employed to obtain the age of twelve obsidian sample from Ecuador. By using the plateau-age correction method, we obtained the true age of each sample and were able to identify four groups of ages in the studied area. Thereafter we studied the fading of fission tracks in two obsidian samples with different origins: Yanaurcu, Ecuador and Monte Arci, Italy. We constructed Arrhenius plots and calculated activation energies for both samples. The results from thermal annealing experiments were compared with theoretical curves obtained by integrating an equation proposed by Shukolyukov et al (1965). (author). 43 refs, 20 figs, 10 tabs

  16. External beam milli-PIXE as analytical tool for Neolithic obsidian provenance studies

    Energy Technology Data Exchange (ETDEWEB)

    Constantinescu, B.; Cristea-Stan, D. [National Institute for Nuclear Physics and Engineering Horia Hulubei, Bucharest-Magurele (Romania); Kovács, I.; Szõkefalvi-Nagy, Z. [Wigner Research Centre for Phyics, Institute for Particle and Nuclear Physics, Budapest (Hungary)

    2013-07-01

    Full text: Obsidian is the most important archaeological material used for tools and weapons before metals appearance. Its geological sources are limited and concentrated in few geographical zones: Armenia, Eastern Anatolia, Italian Lipari and Sardinia islands, Greek Melos and Yali islands, Hungarian and Slovak Tokaj Mountains. Due to this fact, in Mesolithic and Neolithic periods obsidian was the first archaeological material intensively traded even at long distances. To determine the geological provenance of obsidian and to identify the prehistoric long-range trade routes and possible population migrations elemental concentration ratios can help a 101, since each geological source has its 'fingerprints'. In this work external milli-PIXE technique was applied for elemental concentration ratio determinations in some Neolithic tools found in Transylvania and in the lron Gales region near Danube, and on few relevant geological samples (Slovak Tokaj Mountains, Lipari,Armenia). In Transylvania (the North-Western part of Romania, a region surrounded by Carpathian Mountains), Neolithic obsidian tools were discovered mainly in three regions: North-West - Oradea (near the border with Hungary, Slovakia and Ukraine), Centre -Cluj and Southwest- Banat (near the border with Serbia). A special case is lron Gales - Mesolithic and Early Neolithic sites, directly related to the appearance of agriculture replacing the Mesolithic economy based on hunting and fishing. Three long-distance trade routes could be considered: from Caucasus Mountains via North of the Black Sea, from Greek islands or Asia Minor via ex-Yugoslavia area or via Greece-Bulgaria or from Central Europe- Tokaj Mountains in the case of obsidian. As provenance 'fingerprints', we focused on Ti to Mn, and Rb-Sr-Y-Zr ratios. The measurements were performed at the external milli-PIXE beam-line of the 5MV VdG accelerator of the Wigner RCP. Proton energy of 3MeV and beam currents in the range of 1 ±1 D

  17. External beam milli-PIXE as analytical tool for Neolithic obsidian provenance studies

    International Nuclear Information System (INIS)

    Constantinescu, B.; Cristea-Stan, D.; Kovács, I.; Szõkefalvi-Nagy, Z.

    2013-01-01

    Full text: Obsidian is the most important archaeological material used for tools and weapons before metals appearance. Its geological sources are limited and concentrated in few geographical zones: Armenia, Eastern Anatolia, Italian Lipari and Sardinia islands, Greek Melos and Yali islands, Hungarian and Slovak Tokaj Mountains. Due to this fact, in Mesolithic and Neolithic periods obsidian was the first archaeological material intensively traded even at long distances. To determine the geological provenance of obsidian and to identify the prehistoric long-range trade routes and possible population migrations elemental concentration ratios can help a 101, since each geological source has its 'fingerprints'. In this work external milli-PIXE technique was applied for elemental concentration ratio determinations in some Neolithic tools found in Transylvania and in the lron Gales region near Danube, and on few relevant geological samples (Slovak Tokaj Mountains, Lipari,Armenia). In Transylvania (the North-Western part of Romania, a region surrounded by Carpathian Mountains), Neolithic obsidian tools were discovered mainly in three regions: North-West - Oradea (near the border with Hungary, Slovakia and Ukraine), Centre -Cluj and Southwest- Banat (near the border with Serbia). A special case is lron Gales - Mesolithic and Early Neolithic sites, directly related to the appearance of agriculture replacing the Mesolithic economy based on hunting and fishing. Three long-distance trade routes could be considered: from Caucasus Mountains via North of the Black Sea, from Greek islands or Asia Minor via ex-Yugoslavia area or via Greece-Bulgaria or from Central Europe- Tokaj Mountains in the case of obsidian. As provenance 'fingerprints', we focused on Ti to Mn, and Rb-Sr-Y-Zr ratios. The measurements were performed at the external milli-PIXE beam-line of the 5MV VdG accelerator of the Wigner RCP. Proton energy of 3MeV and beam currents in the range of 1 ±1 D

  18. Geochemistry of obsidian from Krasnoe Lake on the Chukchi Peninsula (Northeastern Siberia)

    Science.gov (United States)

    Popov, V. K.; Grebennikov, A. V.; Kuzmin, Ya. V.; Glascock, M. D.; Nozdrachev, E. A.; Budnitsky, S. Yu.; Vorobey, I. E.

    2017-09-01

    This report considers features of the geochemical composition of obsidian from beach sediments of Krasnoe Lake along the lower course of the Anadyr River, as well as from lava-pyroclastic rocks constituting the lake coastal outcrops and the surrounding branches of Rarytkin Ridge. The two geochemical types of obsidian, for the first time distinguished and researched, correspond in their chemical composition to lavas and ignimbrite-like tuffs of rhyolites from the Rarytkin area. The distinguished types represent the final stage of acidic volcanism in the West Kamchatkan-Koryak volcanic belt. It was assumed that the accumulation of obsidian in coastal pebble beds was caused by the erosion of extrusive domes and pyroclastic flows. The geochemical studies of obsidian artifacts from archeological sites of the regions of the Sea of Okhotsk, the Kolyma River, and the Chukchi Peninsula along with the correlation of geological and archeological samples show that Krasnoe Lake was an important source of "archeological" obsidian in Northeastern Siberia.

  19. Elemental, isotopic, and geochronological variability in Mogollon-Datil volcanic province archaeological obsidian, southwestern USA: Solving issues of intersource discrimination

    Science.gov (United States)

    Shackley, M. Steven; Morgan, Leah; Pyle, Douglas

    2017-01-01

    Solving issues of intersource discrimination in archaeological obsidian is a recurring problem in geoarchaeological investigation, particularly since the number of known sources of archaeological obsidian worldwide has grown nearly exponentially in the last few decades, and the complexity of archaeological questions asked has grown equally so. These two parallel aspects of archaeological investigation have required more exacting understanding of the geological relationship between sources and the more accurate analysis of these sources of archaeological obsidian. This is particularly the case in the North American Southwest where the frequency of archaeological investigation is some of the highest in the world, and the theory and method used to interpret that record has become increasingly nuanced. Here, we attempt to unravel the elemental similarity of archaeological obsidian in the Mogollon-Datil volcanic province of southwestern New Mexico where some of the most important and extensively distributed sources are located and the elemental similarity between the sources is great even though the distance between the sources is large. Uniting elemental, isotopic, and geochronological analyses as an intensive pilot study, we unpack this complexity to provide greater understanding of these important sources of archaeological obsidian.

  20. PIXE characterization of Western Mediterranean and Anatolian obsidians and Neolithic provenance studies

    International Nuclear Information System (INIS)

    Le Bourdonnec, F.-X.; Delerue, S.; Dubernet, S.; Moretto, Ph.; Calligaro, Th.; Dran, J.-C.; Poupeau, G.

    2005-01-01

    The possibility of non-destructive elemental analysis makes PIXE a very attractive technique in archaeological provenance studies. This technique has been fruitfully implemented on two different facilities to address the issue of obsidian provenance in the Mediterranean and in surrounding regions. At C2RMF, we took advantage of the possibility to analyze large archaeological pieces with the external micro-beam set-up. At CENBG, we used the nuclear microprobe providing a 5 μm beam diameter in large scans (700 x 700 μm 2 ) to control the homogeneity of elemental distribution. In both cases we dosed the same set of 13 elements: Na, Al, Si, K, Ca, Ti, Mn, Fe, Zn, Ga, Rb, Sr and Zr. While at C2RMF, two Si(Li) detectors were used simultaneously to measure all elements at once with 3 MeV protons, at CENBG where only one detector was available, the light elements Na to Fe were determined with a 1.5 MeV beam, and the heavy ones, including Fe, with a beam energy of 2.7 MeV. In Western Mediterranean, it is possible with PIXE to differentiate all obsidian sources of archaeological significance. Examples are given of obsidian provenances from Neolithic sites of France and from the islands of Corsica and Sardinia. In the Near East, we can differentiate the Cappadocian and Eastern Anatolian obsidian sources used during the early Neolithic. This is illustrated by examples taken from Neolithic sites of the Middle Euphrates Valley (Syria)

  1. Obsidian sources of the Coromandel Volcanic Zone, nortthern New Zealand

    International Nuclear Information System (INIS)

    Moore, P.R.

    2013-01-01

    The Coromandel Volcanic Zone includes nine geographically discrete obsidian sources (Fanal, Awana, Te Ahumata, Cooks Beach, Hahei, Tairua, Whangamata, Maratoto and Waihi). Each has a distinctive chemical composition, and some can also be differentiated on the basis of visual characteristics of the obsidian. Chemically, the three northern sources (Fanal, Awana, Te Ahumata), constituting the 'Great Barrier Group', are distinguished by high Rb concentrations and a high Rb/Sr ratio. Obsidian from six of the sources is known to have been utilized by pre-European Maori for the manufacture of flake tools, but at present there is no evidence for exploitation of the Awana, Maratoto and Tairua deposits. (author). 54 refs., 5 figs., 2 tabs.

  2. Obsidian hydration profiles measured by sputter-induced optical emission.

    Science.gov (United States)

    Tsong, I S; Houser, C A; Yusef, N A; Messier, R F; White, W B; Michels, J W

    1978-07-28

    The variation of concentrations of hydrogen, sodium, potassium, lithium, calcium, magnesium, silicon, and aluminum as a function of depth in the hydration layer of obsidian artifacts has been determined by sputter-induced optical emission. The surface hydration is accompanied by dealkalization, and there is a buildup of alkaline earths, calcium and magnesium in the outermost layers. These results have clarified the phenomena underlying the obsidian hydration dating technique.

  3. Twenty thousand years of changing obsidian trade in Melanesia

    Energy Technology Data Exchange (ETDEWEB)

    White, J. P. [University Of Sydney, NSW (Australia). Archaeloogy; Torrence, R. [Australian Museum, Sydney, NSW (Australia). Anthropology

    1998-12-31

    Archaeological investigations on a range of sites in the Pacific Region identified four well separated obsidian flows which varied in terms of their spatial scale, ease of extraction of raw material, and quality of obsidian for artefact manufacture. Extensive deposits of the by-products from quarrying and artefact manufacture were associated with each flow. Using enhancements in PIXE-PIGME, a finer discrimination was achieved that has allowed each artefact to be assigned to one of the four sub-regions in the Willaumez Peninsular group. These results have led to a better understanding of ancient trade practices. Further analyses of archaeological materials from multiple sites in the Bismarck Archipelago have shown: 1. During the Pleistocene (20,000 - 10,000 years ago) obsidian from both major source regions was repeatedly moved to New Ireland, a distance of some 600 km. The Mopir source predominated. 2. In the period 3500-1500 years ago Mopir was very rare probably because the source was cut off due to a massive volcanic eruption. 3. Although proximity to outcrop is usually the major factor in determining which obsidian was used, one excellent sub-source, Baki on Garua Island, was almost never traded and was not always even the preferred source locally

  4. Twenty thousand years of changing obsidian trade in Melanesia

    International Nuclear Information System (INIS)

    White, J. P.; Torrence, R.

    1998-01-01

    Archaeological investigations on a range of sites in the Pacific Region identified four well separated obsidian flows which varied in terms of their spatial scale, ease of extraction of raw material, and quality of obsidian for artefact manufacture. Extensive deposits of the by-products from quarrying and artefact manufacture were associated with each flow. Using enhancements in PIXE-PIGME, a finer discrimination was achieved that has allowed each artefact to be assigned to one of the four sub-regions in the Willaumez Peninsular group. These results have led to a better understanding of ancient trade practices. Further analyses of archaeological materials from multiple sites in the Bismarck Archipelago have shown: 1. During the Pleistocene (20,000 - 10,000 years ago) obsidian from both major source regions was repeatedly moved to New Ireland, a distance of some 600 km. The Mopir source predominated. 2. In the period 3500-1500 years ago Mopir was very rare probably because the source was cut off due to a massive volcanic eruption. 3. Although proximity to outcrop is usually the major factor in determining which obsidian was used, one excellent sub-source, Baki on Garua Island, was almost never traded and was not always even the preferred source locally

  5. Archaeological obsidian from La Sierra Gorda Mexico, by PIXE

    International Nuclear Information System (INIS)

    Juarez-Cossio, D.; Terreros, E.; Quiroz-Moreno, J.; Romero-Sanchez, S.; Calligaro, T.F.; Tenorio, D.; Jimenez-Reyes, M.; Los Rios, M. de

    2009-01-01

    The chemical compositions of 42 obsidian pre-Hispanic artifacts from Tancama and Purisima, both archaeological sites of La Sierra Gorda Valleys, Mexico, were analyzed by PIXE technique. These obsidians came from four sources: Sierra de Pachuca Hidalgo, Paraiso Queretaro, Ucareo Michoacan and mainly from Zacualtipan/Metzquititlan Hidalgo. According to archaeological evidences, La Sierra Gorda valleys participated in commercial exchange with other regional sites, from Classic to Post-classic periods (A.D. 300-1500).

  6. Strategies for obtaining obsidian in pre-European contact era New Zealand.

    Science.gov (United States)

    McCoy, Mark D; Carpenter, Jonathan

    2014-01-01

    Archaeological evidence of people's choices regarding how they supply themselves with obsidian through direct access and different types of exchanges gives us insight in to mobility, social networks, and property rights in the distant past. Here we use collections of obsidian artefacts that date to a period of endemic warfare among Maori during New Zealand's Late Period (1500-1769 A.D.) to determine what strategies people engaged in to obtain obsidian, namely (1) collecting raw material directly from a natural source, (2) informal trade and exchange, and (3) formal trade and exchange. These deposits represent a good cross-section of Late Period archaeology, including primary working of raw material at a natural source (Helena Bay), undefended sites where people discarded rubbish and worked obsidian (Bream Head), and a heavily fortified site (Mt. Wellington). We find that most of the obsidian described here was likely obtained directly from natural sources, especially those located on off-shore islands within about 60-70 km of sites. A smaller amount comes from blocks of material transported from an off-shore island a greater distance away, called Mayor Island, in a formal trade and exchange network. This study demonstrates the value of conducting tandem lithic technology and geochemical sourcing studies to understand how people create and maintain social networks during periods of warfare.

  7. Strategies for obtaining obsidian in pre-European contact era New Zealand.

    Directory of Open Access Journals (Sweden)

    Mark D McCoy

    Full Text Available Archaeological evidence of people's choices regarding how they supply themselves with obsidian through direct access and different types of exchanges gives us insight in to mobility, social networks, and property rights in the distant past. Here we use collections of obsidian artefacts that date to a period of endemic warfare among Maori during New Zealand's Late Period (1500-1769 A.D. to determine what strategies people engaged in to obtain obsidian, namely (1 collecting raw material directly from a natural source, (2 informal trade and exchange, and (3 formal trade and exchange. These deposits represent a good cross-section of Late Period archaeology, including primary working of raw material at a natural source (Helena Bay, undefended sites where people discarded rubbish and worked obsidian (Bream Head, and a heavily fortified site (Mt. Wellington. We find that most of the obsidian described here was likely obtained directly from natural sources, especially those located on off-shore islands within about 60-70 km of sites. A smaller amount comes from blocks of material transported from an off-shore island a greater distance away, called Mayor Island, in a formal trade and exchange network. This study demonstrates the value of conducting tandem lithic technology and geochemical sourcing studies to understand how people create and maintain social networks during periods of warfare.

  8. Obsidian hydration dating of volcanic events

    Science.gov (United States)

    Friedman, I.; Obradovich, J.

    1981-01-01

    Obsidian hydration dating of volcanic events had been compared with ages of the same events determined by the 14C and KAr methods at several localities. The localities, ranging in age from 1200 to over 1 million yr, include Newberry Craters, Oregon; Coso Hot Springs, California; Salton Sea, California; Yellowstone National Park, Wyoming; and Mineral Range, Utah. In most cases the agreement is quite good. A number of factors including volcanic glass composition and exposuretemperature history must be known in order to relate hydration thickness to age. The effect of composition can be determined from chemical analysis or the refractive index of the glass. Exposure-temperature history requires a number of considerations enumerated in this paper. ?? 1981.

  9. Hydration rate of obsidian.

    Science.gov (United States)

    Friedman, I; Long, W

    1976-01-30

    The hydration rates of 12 obsidian samples of different chemical compositions were measured at temperatures from 95 degrees to 245 degrees C. An expression relating hydration rate to temperature was derived for each sample. The SiO(2) content and refractive index are related to the hydration rate, as are the CaO, MgO, and original water contents. With this information it is possible to calculate the hydration rate of a sample from its silica content, refractive index, or chemical index and a knowledge of the effective temperature at which the hydration occurred. The effective hydration temperature can be either measured or approximated from weather records. Rates have been calculated by both methods, and the results show that weather records can give a good approximation to the true EHT, particularly in tropical and subtropical climates. If one determines the EHT by any of the methods suggested, and also measures or knows the rate of hydration of the particular obsidian used, it should be possible to carry out absolute dating to +/- 10 percent of the true age over periods as short as several years and as long as millions of years.

  10. Obsidian provenance studies in archaeology: A comparison between PIXE, ICP-AES and ICP-MS

    International Nuclear Information System (INIS)

    Bellot-Gurlet, Ludovic; Poupeau, Gerard; Salomon, Joseph; Calligaro, Thomas; Moignard, Brice; Dran, Jean-Claude; Barrat, Jean-Alix; Pichon, Laurent

    2005-01-01

    Elemental composition fingerprinting by PIXE technique is very attractive for obsidian provenance studies as it may proceed in a non-destructive mode, even if a more complete elemental characterization can be obtained by ICP-MS and/or ICP-AES. Only few studies have compared results obtained by both methods for solid rock samples. In this work, elemental compositions were determined by ICP-MS/-AES for international geochemical standards and by ICP-MS/-AES and PIXE for inter-laboratory reference obsidians. In addition 49 obsidian source samples and artefacts were analysed by both ICP-MS/-AES and PIXE. Instrumental work and measurement quality control performed for obsidian chemical characterization, underline that PIXE and ICP-MS/-AES provide reproducible, accurate and comparable measurements. In some volcanic districts the limited number of elements dosed by PIXE is sufficient for the discrimination of the potential raw sources of obsidians. Therefore, PIXE can be an advantageous substitute to ICP-MS/-AES techniques for provenance studies

  11. Emplacement model of obsidian-rhyolite magma deduced from complete internal section of the Akaishiyama lava, Shirataki, northern Hokkaido, Japan

    Science.gov (United States)

    Wada, K.; Sano, K.

    2016-12-01

    Simultaneously explosive and effusive eruptions of silicic magmas has shed light on the vesiculation and outgassing history of ascending magmas in the conduit and emplacement model of obsidian-rhyolite lavas (Castro et al., 2014; Shipper et al, 2013). As well as the knowledge of newly erupted products such as 2008-2009 Chaitén and 2011-2012 Cordón Caule eruptions, field and micro-textural evidences of well-exposed internal structure of obsidian-rhyolite lava leads to reveal eruption processes of silicic magmas. The Shirataki monogenetic volcano field, 2.2 million year age, northern Hokkaido, Japan, contains many outcrops of obsidian and vesiculated rhyolite zones (SiO2=76.7-77.4 wt.%). Among their outcrops, Akaishiyama lava shows good exposures of internal sections from the top to the bottom along the Kyukasawa valley with thickness of about 190 meters, showing the symmetrical structure comprising a upper clastic zone (UCZ; 5m thick), an upper dense obsidian zone (UDO; 15m), an upper banded obsidian zone (UBO; 70-80m), a central rhyolite zone (CR; 65m), a lower banded obsidian zone (LBO; 15m), a lower dense obsidian zone (LDO; 20m), and a lower clastic zone (LCZ; 3m). The upper banded obsidian zone is characterized by existence of spherulite concentration layers with tuffisite veins and rhyolite enclaves. Spherulites consisting of albite, cristobalaite and obsidian glass, are clustered in the dense obsidian. Tuffisite veins show brecciated obsidians in tuffaceous matrix, showing an outgassing path during the emplacement of obsidian lava. Perpendicular dip of spherulite parallel rows indicates the banded zone itself was the domain of vent area. From the observation of these occurrences in the internal section and rock texture, we show the qualitative formation model of Shirataki obsidian-rhyolite lava.

  12. Magma fracturing and degassing associated with obsidian formation: The explosive–effusive transition

    Science.gov (United States)

    Cabrera, Agustin; Weinberg, Roberto; Wright, Heather M.

    2015-01-01

    This paper explores the role of melt fracturing in degassing rhyolitic volcanic systems. The Monte Pilato-Rocche Rosse eruptions in Italy evolved from explosive to effusive in style, and H2O content in quenched glasses changed over time from relatively H2O-rich (~ 0.90 wt.%) to H2O-poor dense obsidian (~ 0.10–0.20 wt.%). In addition, healed fractures have been recorded in all different eruptive materials, from the glass of early-erupted tube pumice and rinds of breadcrusted obsidian pyroclasts, to the glass of late-erupted dense obsidian pyroclasts, and throughout the final effusive Rocche Rosse lava flow. These rocks show multiple fault sets, some with crenulated fault planes indicating resumption of viscous flow after faulting, complex obsidian breccias with evidence for post-brecciation folding and stretching, and centimetre- to metre-thick tuffisite preserved in pyroclasts and lava, representing collapsed foam due to fracturing of vesicle walls. These microstructural observations indicate that multiple fracturing and healing events occurred during both explosive and effusive eruptions. H2O content in glass decreases by as much as 0.14 wt.% towards healed fractures/faults and decreases in stretched obsidian breccias towards regions of intense brecciation. A drop in pressure and/or increase in temperature along fractures caused diffusive H2O migration through melt towards fracture surfaces. Repetitive and pervasive fracturing and healing thereby create conditions for diffusive H2O loss into fractures and subsequent escape through permeable paths. This type of progressive magma degassing provides a potential mechanism to explain the formation of dense obsidian and the evolution from explosive to effusive eruption style.

  13. Cultural distribution of obsidian along the Waikato-King Country coastline, North Island, New Zealand

    International Nuclear Information System (INIS)

    Moore, P.R.

    2011-01-01

    Analysis of obsidian artefact assemblages from fifteen 'early' (pre-AD 1500) Maori sites along an almost 150 km long stretch of the Waikato-King Country coastline in the western North Island shows that while most are dominated by material from Mayor Island, they also contain a significant proportion of 'grey' obsidian (grey in transmitted light) from two main source areas - Taupo, and Cooks Beach-Hahei on Coromandel Peninsula. The presence of obsidian from these two source areas in a relatively large number of 'early' sites is suggestive of a well-developed exchange network, involving a continuing connection with the same sources over a considerable period of time, perhaps 50-100 years. Possible transportation routes for the obsidian are discussed. (author). 25 refs., 4 figs., 2 tabs.

  14. Identification of the source of manufacture of obsidian through the dating with the method of fission track

    International Nuclear Information System (INIS)

    Arias, C.; Bigazzi, G.; Bonadonna, F.P.; Radi, G.; Bernardes, C.; Hadler Neto, J.C.; Lattes, C.M.G.; Araya, A.M.O.; Oliveira, J.X.

    1986-01-01

    Identification of the source of manufacture of obsidian through the dating with the method of fission track. After a brief description of fission track dating method and of the problems related to its application to volcanic glasses, we show and discuss data about obsidians of geological origin from Mediterranean basin and Latin America and of archaeological origin found in prehistoric sites from Italian peninsula. The analysis of the results shows the excellent performance of fission track method to identify the provenance of obsidians of archaeological origin, provided important constributions both from the methodological pointo of view-excellent agreement between the two correction techniques of apparent ages, size-correction technique and plateau age -, as from the archaeological point of view - we could identify four possible sources of provenance in Italy, the obsidian from Monte Arci, Sardinia, the obsidian from Pahnarola island, the obsidian from Gabelloto, Lipari island and the obsidian from Balata dei Turchi, Pantelleria island; and it ca be shown that Lipari obsidian began to be used at a very antique phase of neolithic period. The data about Latin American samples, though fragmented, constitute in an inicial study promissing perpectives as it can be observed by the comparisions made with the data published by others authors about geologic and archaeologic samples from the same area. (Author) [pt

  15. Discrimination of surface wear on obsidian tools using LSCM and RelA: pilot study results (area-scale analysis of obsidian tool surfaces).

    Science.gov (United States)

    Stemp, W James; Chung, Steven

    2011-01-01

    This pilot study tests the reliability of laser scanning confocal microscopy (LSCM) to quantitatively measure wear on experimental obsidian tools. To our knowledge, this is the first use of confocal microscopy to study wear on stone flakes made from an amorphous silicate like obsidian. Three-dimensional surface roughness or texture area scans on three obsidian flakes used on different contact materials (hide, shell, wood) were documented using the LSCM to determine whether the worn surfaces could be discriminated using area-scale analysis, specifically relative area (RelA). When coupled with the F-test, this scale-sensitive fractal analysis could not only discriminate the used from unused surfaces on individual tools, but was also capable of discriminating the wear histories of tools used on different contact materials. Results indicate that such discriminations occur at different scales. Confidence levels for the discriminations at different scales were established using the F-test (mean square ratios or MSRs). In instances where discrimination of surface roughness or texture was not possible above the established confidence level based on MSRs, photomicrographs and RelA assisted in hypothesizing why this was so. Copyright © 2011 Wiley Periodicals, Inc.

  16. Origin identification for Cantona, Puebla, obsidians by the analysis method of neutron activation (NAA)

    International Nuclear Information System (INIS)

    Tellez N, A. L.

    2013-01-01

    There are tests that most of the obsidian worked in the workshops of Cantona, Puebla, is coming from the mineral deposits of Oyameles-Zaragoza, but also has been detected obsidian that macroscopically belongs to other mineral deposits. The present work has as purpose to determine the provenance of an obsidian sample obtained in the Cantona Site to know if there was the presence of obsidian of other mineral deposits. For the study the neutron activation analysis was used to identify the presence of other deposits. An explanation on the treatment to the selected pieces is included, the preparation of the same ones for its irradiation in the nuclear reactor, the counting and statistical study of the results. Finally the results of the selected samples are presented, indicating their origin places, that time comes and the interpretation of the results is given. (Author)

  17. Obsidian dating and East african archeology.

    Science.gov (United States)

    Michels, J W; Tsong, I S; Nelson, C M

    1983-01-28

    New experimental procedures have made it possible to establish specific hydration rates for the numerous compositional types of obsidian to be found at archeological sites in Kenya. Two rates are applied to artifacts from the Prospect Farm site, revealing a history of occupation extending back 120,000 years.

  18. Breakthrough in precision (0.3 percent) of neutron activation analyses applied to provenience studies of obsidian

    International Nuclear Information System (INIS)

    Asaro, Frank; Stross, Fred H.; Burger, Richard L.

    2002-01-01

    A gamma ray spectrometer at LBNL (the Luis W. Alvarez Iridium Coincidence Spectrometer), that was specifically designed for high sensitivity measurements of iridium abundances, has been significantly modified in order to provide precisions of measurement in neutron activation analysis of obsidian significantly better than previously obtained (about 1%). Repeated measurements on a single sample of obsidian from a deposit near Chivay, Arequipa, Peru, showed a precision (average coefficient of variation) of 0.19% for the 6 best-measured elements, the value anticipated from the known random errors of measurement. In measurement of samples made from 7 different obsidian nodules from two locations near Chivay, a group of 5 had a spread of 0.30% for the 6 elements measured with counting statistics of better than 0.3% (and 1.8% for the remaining 6 elements). The data suggest there are source inhomogeneity and/or sample preparation contamination errors totaling 0.24 ± .05% for the 6 best measured elements. A sixth obsidian sample could be distinguished from the main group because it differed by +0.8% for most elements, and the last sample could be easily distinguished because several elements differed by more than 1%. The precision of measurements now being developed may provide a significantly more precise determination of the provenience of obsidian artifacts than has been heretofore possible. Also the techniques of measurement developed for obsidian will provide even better precisions with pottery, as many elements are more abundant in pottery than in obsidian

  19. Breakthrough in precision (0.3 percent) of neutron activation analyses applied to provenience studies of obsidian

    Energy Technology Data Exchange (ETDEWEB)

    Asaro, Frank; Stross, Fred H.; Burger, Richard L.

    2002-10-01

    A gamma ray spectrometer at LBNL (the Luis W. Alvarez Iridium Coincidence Spectrometer), that was specifically designed for high sensitivity measurements of iridium abundances, has been significantly modified in order to provide precisions of measurement in neutron activation analysis of obsidian significantly better than previously obtained (about 1%). Repeated measurements on a single sample of obsidian from a deposit near Chivay, Arequipa, Peru, showed a precision (average coefficient of variation) of 0.19% for the 6 best-measured elements, the value anticipated from the known random errors of measurement. In measurement of samples made from 7 different obsidian nodules from two locations near Chivay, a group of 5 had a spread of 0.30% for the 6 elements measured with counting statistics of better than 0.3% (and 1.8% for the remaining 6 elements). The data suggest there are source inhomogeneity and/or sample preparation contamination errors totaling 0.24 {+-} .05% for the 6 best measured elements. A sixth obsidian sample could be distinguished from the main group because it differed by +0.8% for most elements, and the last sample could be easily distinguished because several elements differed by more than 1%. The precision of measurements now being developed may provide a significantly more precise determination of the provenience of obsidian artifacts than has been heretofore possible. Also the techniques of measurement developed for obsidian will provide even better precisions with pottery, as many elements are more abundant in pottery than in obsidian.

  20. Advanced signal processing analysis of laser-induced breakdown spectroscopy data for the discrimination of obsidian sources.

    Science.gov (United States)

    Remus, Jeremiah J; Harmon, Russell S; Hark, Richard R; Haverstock, Gregory; Baron, Dirk; Potter, Ian K; Bristol, Samantha K; East, Lucille J

    2012-03-01

    Obsidian is a natural glass of volcanic origin and a primary resource used by indigenous peoples across North America for making tools. Geochemical studies of obsidian enhance understanding of artifact production and procurement and remain a priority activity within the archaeological community. Laser-induced breakdown spectroscopy (LIBS) is an analytical technique being examined as a means for identifying obsidian from different sources on the basis of its 'geochemical fingerprint'. This study tested whether two major California obsidian centers could be distinguished from other obsidian localities and the extent to which subsources could be recognized within each of these centers. LIBS data sets were collected in two different spectral bands (350±130 nm and 690±115 nm) using a Nd:YAG 1064 nm laser operated at ~23 mJ, a Czerny-Turner spectrograph with 0.2-0.3 nm spectral resolution and a high performance imaging charge couple device (ICCD) detector. Classification of the samples was performed using partial least-squares discriminant analysis (PLSDA), a common chemometric technique for performing statistical regression on high-dimensional data. Discrimination of samples from the Coso Volcanic Field, Bodie Hills, and other major obsidian areas in north-central California was possible with an accuracy of greater than 90% using either spectral band. © 2012 Optical Society of America

  1. Formation of obsidian pyroclasts by sintering of ash particles in the volcanic conduit

    Science.gov (United States)

    Gardner, James E.; Llewellin, Edward W.; Watkins, James M.; Befus, Kenneth S.

    2017-02-01

    The ranges in intensity and style of volcanic eruptions, from highly explosive Plinian eruptions to quiescent lava extrusions, depend on the style and efficiency of gas loss from ascending magma. Obsidian pyroclasts - small, glassy pieces of quenched magma found in some volcanic tephra beds - may preserve valuable information about magma degassing in their vesicle textures and volatile contents. Accurate interpretation of their textures and volatiles, however, requires understanding the mechanism of formation of the pyroclasts. Obsidian pyroclasts from the ca. 1325-1350 C.E. North Mono eruption of Mono Craters (CA, USA) were analyzed and found to have H2O and CO2 contents indicating that they were formed at pressures in the approximate range of 3-40 MPa. Many also contain domains with differing vesicle textures, separated by boundaries containing xenocrystic material, indicating that they are composed of smaller fragments that have sutured together. More than half of the pyroclasts analyzed contained small (∼10 μm), highly distorted vesicles, with multi-cuspate morphology, interpreted as the remnants of interstitial gas trapped amongst sintered fragments of melt/glass. Rounded vesicles are also common and are interpreted to result from surface tension-driven relaxation of the distorted vesicles. Calculated timescales of sintering and relaxation are consistent with timescales for pyroclast formation indicated by H2O re-equilibration within the heterogeneous pyroclasts. This sintering model for the origin of obsidian pyroclasts is further supported by the observation that spherical vesicles are found mainly in H2O-rich pyroclasts, and distorted vesicles mainly in H2O-poor pyroclasts. We conclude that obsidian pyroclasts generated during the North Mono eruption were formed by cycles of fragmentation, sintering/suturing, and relaxation, over a very wide range of depths within the conduit; we find no evidence to support pumice (foam) collapse as the formation

  2. PIXE analysis of cave sediments, prehispanic paintings and obsidian cutting tools from Baja California Sur caves

    International Nuclear Information System (INIS)

    Miranda, J.; Oliver, A.; Dacal, A.; Ruvalcaba, J.L.; Cruz, F.; Ortiz, M.E.; Vinas, R.

    1993-01-01

    Elemental PIXE analysis of cave sediments, minerals, pigments of the prehispanic paintings and obsidian cutting tools from caves in Baja California Sur has been carried out with a 0.7 MeV proton beam. The elements analysed in this sample set (Al to Co) provide an idea of the environment of the caves. The obsidian data analysis suggests that the human communities who made these painting used more than one obsidian source to manufacture cutting tools. (orig.)

  3. Obsidian Hydration Dating in the Undergraduate Curriculum.

    Science.gov (United States)

    Manche, Emanuel P.; Lakatos, Stephen

    1986-01-01

    Provides an overview of obsidian hydration dating for the instructor by presenting: (1) principles of the method; (2) procedures; (3) applications; and (4) limitations. The theory of the method and one or more laboratory exercises can be easily introduced into the undergraduate geology curriculum. (JN)

  4. The analysis of pre-hispanic obsidians by the neutron activation technique

    International Nuclear Information System (INIS)

    Esparza L, R.; Tenorio C, D.; Jimenez R, M.

    2005-01-01

    The project called Bank of Data of the locations of obsidian of the occident of Mexico (Analysis by Neutron activation) as it has been explained, for the use of the Neutron activation analysis in archaeological materials it was developed from the years 1960. In Mexico it use is unfortunately very later, until the middle of the decade of 1990 the first studies were made. Without a doubt we face a bigger challenge which consists on creating databases of different materials to have comparison parameters of the studied materials. In the foreigner's different institutions (Missouri Research Reactor, University of Berkeley, among other) it has been of great importance the possibility to be able to compare the databases of each investigation with other coming from different institutions. The results to that have arrived even present certain error margin using the same study patterns, for what is advisable to only use own databases; for it, in the project of this investigation it is sought that the Nuclear Center has its own wealth of information of the different obsidian locations that they exist in the Mexican territory, so that later on the reliable analysis of materials coming from different archaeological places is made to know its origin. Thirteen obsidian locations were analyzed that are located in the states of Michoacan, Jalisco, Guanajuato and Zacatecas. The geologic samples were obtained of different investigation projects, of the National Institute of Anthropology and History, of the Center of Meso-American Studies and of Central America (CEMCA) and of the New Orleans University. One of the problems that face when studying the obsidian locations in the occident of Mexico is linked with the variety of colors that they exist in different locations. With it, we want to show the difficulty that it exists to study this material at level 'eye meter', that which could carry errors and graft of the archaeological information. It is for that reason that it becomes

  5. Provenance and use wears of Pre-Hispanic obsidian scrapers from Metztitlan, Hidalgo, Mexico

    International Nuclear Information System (INIS)

    Mandujano, C.; Elizalde, S.; Cassiano, G.; Soto, D.

    2002-01-01

    The research was performed with archaeological obsidian scrapers, collected at the Metztitlan area, Hidalgo, Mexico. The provenance of the raw material was determined by NAA. SEM technique was applied to identify use wears on pre-Hispanic tools and experimental replicas. The Metztitlan scrapers made of the obsidian of Zacualtipan, Hidalgo, Mexico, were probably used for Agave juice extraction in the Late Postclassical period. (author)

  6. Lithics in Neolithic Northern Greece: territorial perspectives from an off-obsidian area

    Directory of Open Access Journals (Sweden)

    Georgia Kourtessi-Philippakis

    2009-12-01

    Full Text Available C. Renfrew’s research in the Aegean at the beginning of the 1970’s and his hypothesis on the diffusion of obsidian from the island of Milos greatly influenced views of Greek Prehistory. Further lithic studies, especially in the Southern Aegean, have served to further confirmation the prevalence of obsidian in this area during the Neolithic. The aim of this paper is to draw attention to areas such as Northern Greece that are situated on the periphery of the Melian obsidian domain, where local materials occur in connection with imported ones from the North and South. With the aid of various examples from major Neolithic sites, we will discuss the question of procurement strategies in association with the reduction sequences of each material in use in this region, and outline trends of territorial organization among Neolithic farmers in the area.

  7. Presentació del llibre La gobernanza hoy: 10 textos de referencia, d'Agustí Cerrillo

    Directory of Open Access Journals (Sweden)

    Agustí Cerrillo

    2006-11-01

    Full Text Available

    El proppassat 19 de gener, es va presentar a la Universitat Oberta de Catalunya el llibre La gobernanza hoy: 10 textos de referencia, coordinat i tradu¨t per Agustí Cerrillo, professor dels Estudis de Dret i Ciència Política de la UOC.

    El van presentar Eduard Aibar, vicerector de recerca de la UOC; Francisco Ramos, director de l'Institut Nacional d'Administració Pública; Joan Prats, director de l'Institut Internacional de Governabilitat de Catalunya i autor del llibre De la burocracia al management. Del management a la gobernanza, que també fou presentat en el mateix acte.

  8. Obsidian deposits in the central Balkans? Tested against archaeological evidence

    Directory of Open Access Journals (Sweden)

    Tripković Boban

    2003-01-01

    Full Text Available Finds of obsidian artefacts on sites distant from the presumed primary source have often received a romantic note in the history of archaeology manifested in the idea about local exploitation as a form of procurement and archaeologists’ search for as yet undetected deposits of this raw material. In due course, such concepts have found their way into Serbian archaeology as well. The main objective of this contribution, therefore, is to reconsider the current knowledge about obsidian in the central and north Balkans, to test how well founded the idea about the use of local sources is, as well as to indicate some possible directions for future research.

  9. Obsidian trade routes in the mayan area.

    Science.gov (United States)

    Hammond, N

    1972-12-08

    Obsidian from two sources in highland Guatemala has been found at 23 sites of the Classic Mayan civilization, mainly in the nonvolcanic lowlands to the north. The distribution, together with trade routes suggested by topography and documentary sources, suggests efficient waterborne transport and competition between sources for the lowland market.

  10. Obsidian from volcanic sequences and rent alluvial deposits, Erzurum district, north-eastern Anatolia: Chemical characterisation and archaeological implications

    International Nuclear Information System (INIS)

    Brennan, P.; Sagona, T.

    1997-01-01

    Full text: Recent geoarchaeological research in the Erzurum district, north-eastern Anatolia, has revealed an abundance of obsidian at numerous neolithic and Bronze Age sites. Geochemical characterisation using neutron activation analysis indicates that the obsidian was obtained from several sources that are chemically distinct from the major sources already known from Central Anatolia an the Lake Van area. Multiple sources are represented in the samples collected from at least two of the sites, namely the sites of Sos and Pulur. The primary source of some of the obsidian utilised at the site of Sos has been located in the volcanic sequence outcropping tot he north-west of Pasinler. Field survey however has shown that the alluvial deposits along the main rivers and some of their tributaries were the main sources of the obsidian utilised at the sites near Erzurum. Trade or exchange of obsidian with sites outside the Erzurum area seems to have been limited

  11. Book review: Twenty-Five Years on the Cutting Edge of Obsidian Studies: Selected Readings from the IAOS Bulletin

    Directory of Open Access Journals (Sweden)

    Sean Dolan

    2017-03-01

    Full Text Available Edited by Carolyn D. Dillian (Coastal Carolina University, Twenty-Five Years on the Cutting Edge of Obsidian Studies: Selected Readings from the IAOS Bulletin consists of 19 previously published articles from the International Association for Obsidian Studies (IAOS Bulletin. Dillian selected these articles because they provide a range of methodological and theoretical approaches concerning archaeological obsidian studies from around the world like Eretria, California, and the Near East, for example.

  12. What have we achieved in Pacific obsidian research?

    International Nuclear Information System (INIS)

    Green, R.

    1997-01-01

    Full text: This paper looks over nearly forty years in the obsidian sourcing and dating business in the Pacific. In particular, it examines the networks and players that produced the most important developments, since these underpin the present healthy state of research in this field

  13. Analytical data of geologic obsidians from Japan by INAA using middle- and long-lived nuclides

    International Nuclear Information System (INIS)

    Watanabe, K.

    2009-01-01

    This paper reports the results of instrumental neutron activation analysis (INAA) on 3,704 obsidian samples, taking the measurements of 23 elements. The results are summarized, combining the results of INAA conducted earlier by AMBIRU et al. on 1,444 samples. The samples for these analyses are taken from seventy obsidian sources located at various places of Japan. (author)

  14. An international research project on Armenian archaeological sites: fission-track dating of obsidians

    Energy Technology Data Exchange (ETDEWEB)

    Badalian, R.; Bigazzi, G. E-mail: g.bigazzi@iggi.pi.cnr.it; Cauvin, M.-C.; Chataigner, C.; Jrbashyan, R.; Karapetyan, S.G.; Oddone, M.; Poidevin, J.-L

    2001-06-01

    In the Mediterranean and adjacent regions, the Caucasus is one of the less studied areas in relation to provenance studies of prehistoric obsidian artefacts. In the frame of an international INTAS research project, an extensive surveying and sampling campaign was carried out in the numerous obsidian bearing volcanic complexes of Armenia. 33 obsidian samples were analysed using the fission-track dating method in order to characterise the potential sources of the numerous artefacts found in prehistoric sites. Ages cluster into five groups--Upper Neopleistocene Q{sub III}, Middle Neopleistocene Q{sub II}, Lower Neopleistocene Q{sub I}, Lower Eopleistocene Q{sub EI} and Lower Pliocene N{sub 3}{sup 1} groups. This research represents a significant contribution to a better knowledge of chronology of Armenian volcanism for which only few data were available. The resulting data-set appears to be a solid base for future provenance studies.

  15. Observations of obsidian lava flow emplacement at Puyehue-Cordón Caulle, Chile

    Science.gov (United States)

    Tuffen, H.; Castro, J. M.; Schipper, C. I.; James, M. R.

    2012-04-01

    The dynamics of obsidian lava flow emplacement remain poorly understood as active obsidian lavas are seldom seen. In contrast with well-documented basaltic lavas, we lack observational data on obsidian flow advance and temporal evolution. The ongoing silicic eruption at Puyehue-Cordón Caulle volcanic complex (PCCVC), southern Chile provides an unprecedented opportunity to witness and study obsidian lava on the move. The eruption, which started explosively on June 4th 2011, has since June 20 generated an active obsidian flow field that remains active at the time of writing (January 2012), with an area of ~6 km2, and estimated volume of ~0.18 km3. We report on observations, imaging and sampling of the north-western lava flow field on January 4th and 10th 2012, when vent activity was characterised by near-continuous ash venting and Vulcanian explosions (Schipper et al, this session) and was simultaneously feeding the advancing obsidian flow (Castro et al, this session). On January 4th the north-western lava flow front was characterised by two dominant facies: predominant rubbly lava approximately 30-40 m thick and mantled by unstable talus aprons, and smoother, thinner lobes of more continuous lava ~50 m in length that extended roughly perpendicular to the overall flow direction, forming lobes that protrude from the flow margin, and lacked talus aprons. The latter lava facies closely resembled squeeze-up structures in basaltic lava flows[1] and appeared to originate from and overlie the talus apron of the rubbly lava. Its upper surface consisted of smooth, gently folded lava domains cut by crevasse-like tension gashes. During ~2 hours of observation the squeeze-up lava lobe was the most frequent location of small-volume rockfalls, which occurred at ~1-10 minute intervals from the flow front and indicated a locus of lava advance. On January 10th the squeeze-up lava lobes had evolved significantly, with disruption and breakage of smooth continuous lava surfaces to form

  16. The source of prehistoric obsidian artefacts from the Polynesian outlier of Taumako in the Solomon Islands

    Energy Technology Data Exchange (ETDEWEB)

    Leach, Foss [Otago Univ., Dunedin (New Zealand). Dept. of Anthropology

    1985-01-01

    Six obsidian artefacts from the Polynesian outlier of Taumako in the Solomon Islands dating to between 500 and 1000 B.C. were analysed for trace elements by the PIXE-PIGME method. Four are shown to derive from Vanuatu, but the remaining two artefacts do not match any of the known 66 sources in the Pacific region. Continuing difficulties with the methodology of Pacific obsidian sourcing are discussed. 14 refs; 2 tables.

  17. The obsidian of the Maltrata valley, Veracruz, origin analysis of the raw material with neutron activation analysis

    International Nuclear Information System (INIS)

    Molina V, R. O.; Jimenez R, M.; Tenorio, D.; Lira L, Y.; Manzanilla, L.

    2009-01-01

    51 archaeological pieces of obsidian coming from the Maltrata valley were analyzed by means of the analysis technique by neutron activation, with the purpose of determining the interchange routes of that region. In accordance with the statistical study of the results, the obsidians of this investigation come from 5 deposits located in: Sierra de las Navajas, Pico de Orizaba, Zaragoza-Oyameles, Otumba and Paredon. The analyzed obsidian fragments were selected in accordance with their raw material type, size, weight, morphology, excavation context and surface. The irradiation of the samples was carried out in the research reactor TRIGA Mark III of the Nuclear Center of Mexico, with a neutrons flow of 1·10 13 n·cm -2 ·s -1 . (Author)

  18. Archaeological application of PIXE-PIGME analysis of admirality islands obsidians

    Energy Technology Data Exchange (ETDEWEB)

    Ambrose, W R [Australian National Univ., Canberra. Dept. of Prehistory; Duerden, P; Bird, J R [Australian Atomic Energy Commission Research Establishment, Lucas Heights

    1982-12-31

    Archaeological research on trade and exchange systems in Melanesia has been advanced by the application of chemical analysis to artefacts and their raw materials. Using the measurement of proton induced X-rays (PIXE) and gamma rays (PIGME), in an automated system, it has been possible to chemically characterise over 2000 obsidian specimens for up to 21 elements. The data analysis has shown that discrimination is possible between source sub-units within a related volcanic suite of sources. The source groups, and the artefacts belonging to them, can be quickly and confidently sorted by applying multivariate clustering and allocation procedures to the data. This work has also shown that obsidian was carried from sources to sites more than 400 km away, across a sea barrier, around 6000 years ago and more than 3000 km from the Bismark Archipelage to Vanuatu (New Hebrides) between 3000-4000 years ago.

  19. Tritium-exchange method for obsidian hydration shell measurement

    Energy Technology Data Exchange (ETDEWEB)

    Lowe, J P; Wilson, A T; Lowe, D J; Hodder, A P.W. [Waikato Univ., Hamilton (New Zealand)

    1984-12-01

    A new radiochemical method for measuring the amount of water in the hydrated layer on the surface of obsidians exchanges tritiated water with the water in the layer (20 ..mu..l of 5 Ci ml/sup -1/ at 90/sup 0/C for 10 days) and then back-exchanges it (in 150 ml of water at 35/sup 0/C for approx. 200 hr.). The activity of the back-exchange water (F) is monitored by liquid scintillation counting of aliquots extracted at known time intervals (t). The activity so measured is then related to the thickness of the hydration rim. A sheet diffusion model shows that the thickness of the hydration shell (l) is inversely proportional to the slope of the F vs. tsup(1/2) plot. Comparison of l-values so obtained between obsidians, whose age (x) is inferred from archaeological occupation layers containing radiocarbon-dated wood and charcoal, suggests a relationship between l and x. Implications for New Zealand prehistory are briefly considered. The technique, which is non-destructive, appears particularly applicable to young glasses where the development of hydrated layers may be inadequate for accurate optical measurement.

  20. Melt fracturing and healing: A mechanism for degassing and origin of silicic obsidian

    Science.gov (United States)

    Cabrera, A.; Weinberg, R.F.; Wright, H.M.N.; Zlotnik, S.; Cas, Ray A.F.

    2011-01-01

    We present water content transects across a healed fault in pyroclastic obsidian from Lami pumice cone, Lipari, Italy, using synchrotron Fourier transform infrared spectroscopy. Results indicate that rhyolite melt degassed through the fault surface. Transects define a trough of low water content coincident with the fault trace, surrounded on either side by high-water-content plateaus. Plateaus indicate that obsidian on either side of the fault equilibrated at different pressure-temperature (P-T) conditions before being juxtaposed. The curves into the troughs indicate disequilibrium and water loss through diffusion. If we assume constant T, melt equilibrated at pressures differing by 0.74 MPa before juxtaposition, and the fault acted as a low-P permeable path for H2O that diffused from the glass within time scales of 10 and 30 min. Assuming constant P instead, melt on either side could have equilibrated at temperatures differing by as much as 100 ??C, before being brought together. Water content on the fault trace is particularly sensitive to post-healing diffusion. Its preserved value indicates either higher temperature or lower pressure than the surroundings, indicative of shear heating and dynamic decompression. Our results reveal that water contents of obsidian on either side of the faults equilibrated under different P-T conditions and were out of equilibrium with each other when they were juxtaposed due to faulting immediately before the system was quenched. Degassing due to faulting could be linked to cyclical seismic activity and general degassing during silicic volcanic activity, and could be an efficient mechanism of producing low-water-content obsidian. ?? 2011 Geological Society of America.

  1. Chemical fingerprinting and source tracing of obsidian: the central Mediterranean trade in black gold.

    Science.gov (United States)

    Tykot, Robert H

    2002-08-01

    Chemical fingerprinting using major or trace element composition is used to characterize the Mediterranean island sources of obsidian and can even differentiate as many as nine flows in the Monte Arci region of Sardinia. Analysis of significant numbers of obsidian artifacts from Neolithic sites in the central Mediterranean reveals specific patterns of source exploitation and suggests particular trade mechanisms and routes. The use of techniques such as X-ray fluorescence, the electron microprobe, neutron activation analysis, and laser ablation ICP mass spectrometry are emphasized in order to produce quantitative results while minimizing damage to valuable artifacts.

  2. The origin and distribution of obsidian in prehistoric Bohemia

    Czech Academy of Sciences Publication Activity Database

    Burgert, Pavel; Přichystal, A.; Prokeš, L.; Petřík, J.; Hušková, S.

    2017-01-01

    Roč. 7, č. 1 (2017), s. 1-15 E-ISSN 1314-5088 R&D Projects: GA ČR GA15-16963S Institutional support: RVO:67985912 Keywords : obsidian * outcrops * raw material distribution * Palaeolithic * Neolithic * geochemistry Subject RIV: AC - Archeology, Anthropology, Ethnology OBOR OECD: Archaeology http://be-ja.org/index.php/Be-JA/article/view/3/1

  3. Analysis of Thousands of Prehistoric Mediterranean Obsidian Artifacts Using a Nondestructive Portable X-Ray Fluorescence Spectrometer

    Science.gov (United States)

    Tykot, Robert

    A portable, hand-held X-ray fluorescence spectrometer has been used for a decade to elementally analyze prehistoric obsidian artifacts in the Mediterranean. Nearly 400 geological obsidian samples and 7500 obsidian artifacts have been analyzed. The pXRF can distinguish all individual sources, as well as assign artifacts specifically to most subsources. For the island sources of Lipari, Pantelleria, Sardinia, and Melos, it is important to address the usage of obsidian from specific subsources due to human selection based on physical properties of the raw material and their production practices, which may have changed over time from the Early Neolithic to the Bronze Age. The analysis of 50 or more artifacts from 60 different archaeological sites allows for statistical comparison between sites, and their contexts, geographic areas (e.g. coastal/inland, highland/lowland) and distance from geological sources. The frequency of transport between island sources and mainland sites is suggestive of maritime capabilities also for the transport of domesticated animals, ceramics, and other materials. This presentation will specifically address potential limitations of the portable XRF, including non-destructive surface analysis of potentially heterogeneous materials, and limited trace element detection compared to other analytical methods, versus its highly beneficial ``package'' of analyzing great numbers of artifacts non-destructively and rapidly without needing to export them from museums and facilities in many countries.

  4. Use of nuclear methods developed around a cyclotron for an archeological obsidian characterization. Application to the study of Near-East sites supplying

    International Nuclear Information System (INIS)

    Khalil Al Isa.

    1990-11-01

    We developed a new bulk non destructive analytical method to source obsidian artefacts with their chemical composition: fast neutron activation analysis using a cyclotron. In a first part we set up the experimental irradiation parameters and we developed a new calibration method allowing both the non determination of the major constituents of obsidian, and the correction of the geometrical factors due to the shape of the objects. Then for the same samples we compare on one hand the results obtained by our method with those obtained by proton activation analysis and on the other hand the results obtained by us with those obtained by other laboratories using other analytical methods. Lastly we show that the application of our method to the study of Near Eastern obsidian artefacts allows a better understanding of the ancient trade routes of obsidian [fr

  5. Jacobsens ukendte samling af stensager fra den græske oldtid. Obsidian, økser, matricer, ansigtssten og andre sjældne oldsager

    DEFF Research Database (Denmark)

    Sørensen, Lasse

    2012-01-01

    Jacobsens ukendte samling af stensager fra den græske oldtid. Obsidian, økser, matricer, ansigtssten og andre sjældne oldsager......Jacobsens ukendte samling af stensager fra den græske oldtid. Obsidian, økser, matricer, ansigtssten og andre sjældne oldsager...

  6. The Maltrata valley in the inter regional trade nets of the obsidian in Meso america: origin by neutron activation

    International Nuclear Information System (INIS)

    Molina V, R. O.

    2011-01-01

    The study of the obsidian in Mexico has included different research lines, as they are: the study of the elaboration techniques of several things, forms, dating: deposits localization and extraction of the raw material; study about the physical and mineralogical characteristics, and those focused to the trade routes of several things; which is developed in this thesis. The topic developed in this research is to propose the possible communication routes in which the obsidian of the Maltrata valley has participated among the Gulf coast and of the Altiplano 12 central. With the characterization study of the obsidian is possible to know the origin of this and also the relationship with other societies, because the exploitation of raw materials of mineral origin was an activity of great economic and politics importance in the pre hispanic societies. When the origin is determined is possible to relate the supplier, with the distributor and consumer and this way to trace on a map the movement routes that people settled down and for those that the obsidian circulated. To define the origin of the Maltrata obsidian was used the analysis technique by neutron activation, which allowed knowing the origin place of the raw material. This work is organized in five chapters. In the first chapter the theoretical and methodological bases are developed to define the research. A revision is made to the antecedents on trade and origin in the center and south of Veracruz. In the second chapter a general panorama of the geographical and geologic environment of the region is described, with the purpose of to delineate the own characteristics of the valley and to distinguish it of the diverse areas and regions of the coast of the Gulf. In the chapter third, the data of the material context and the places of where they took the representative samples are provided; equally the methodology carried out for its selection, classification and registration is presented. For the fourth chapter is

  7. The use of PIXE in the characterisation of thick obsidian samples

    International Nuclear Information System (INIS)

    Duerden, P.; Clayton, E.; Cohen, D.

    1978-01-01

    The proton induced x-ray emission technique has been used for the characterisation of obsidian samples from the S.W. Pacific region (Papua New Guinea, New Hebrides, New Zealand). It is intended to build up a reference library of data so that the origins of artefacts may be traced

  8. Cooling and crystallization of rhyolite-obsidian lava: Insights from micron-scale projections on plagioclase microlites

    Science.gov (United States)

    Sano, Kyohei; Toramaru, Atsushi

    2017-07-01

    To reveal the cooling process of a rhyolite-obsidian flow, we studied the morphology of plagioclase microlites in the Tokachi-Ishizawa lava of Shirataki, northern Hokkaido, Japan, where the structure of the lava can be observed from obsidian at the base of the flow to the innermost rhyolite. Needle-like micron-scale textures, known as "projections", occur on the short side surfaces of the plagioclase microlites. Using FE-SEM we discovered a positive correlation between the lengths and spacings of these projections. On the basis of the instability theory of an interface between melt and crystal, and to understand the length and spacing data, we developed a model that explains the positive correlation and allows us to simultaneously estimate growth rates and growth times. Applying the model to our morphological data and the estimated growth rates and growth times, we suggest that the characteristics of the projections reflect the degree of undercooling, which in turn correlates with lava structure (the obsidian at the margin of the flow experienced a higher degree of undercooling than the interior rhyolite). The newly developed method provides insights into the degree of undercooling during the final stages of crystallization of a rhyolitic lava flow.

  9. The development and application of New Zealand obsidian hydration dating, 1996-1998

    International Nuclear Information System (INIS)

    Sheppard, P.J.; Barker, P.; Irwin, G.J.; Jones, M.; Stevenson, C.; Sutton, D.G.

    1996-01-01

    This article is to inform readers of the continuing development of New Zealand obsidian hydration dating, which has been funded by the Foundation of Research, Science and Technology. This research seeks to date Aotearoa/New Zealand's past on the basis of refinement and strategic application of obsidian hydration dating (OHD), which was successfully developed during 1993-94. It has four objectives. These are: to improve the accuracy and precision of hydration rim measurement using a non-destructive technique; to control and reduce other sources of dating error; to evaluate recently published alternative models of initial Maori colonization and dispersal along the east coast, North Cape to the Bluff; and, to carry out a high resolution dating of the archaeological evidence of pre-European Maori settlement and fortification in the Hauraki Gulf. The rationale of each of these objectives, and the methods used, are outlined. (author). 47 refs., 1 appendix

  10. Prompt Gamma Activation Analysis of the Nyírlugos obsidian core depot find

    Directory of Open Access Journals (Sweden)

    Zsolt Kasztovszky

    2014-03-01

    Full Text Available The Nyírlugos obsidian core depot find is one of the most important lithic assemblages in the collection of the Hungarian National Museum (HNM. The original set comprised 12 giant obsidian cores, of which 11 are currently on the permanent archaeological exhibition of the HNM. One of the cores is known to be inDebrecen. The first publication attributed the hoard, on the strength of giant (flint blades known from the Early and Middle Copper Age Tiszapolgár and Bodrogkeresztúr cultures, to the Copper Age. In the light of recent finds it is more likely to belong to the Middle Neolithic period. The source area was defined as Tokaj Mts., about100 kmto the NW from Nyírlugos. The size and beauty of the exceptional pieces exclude any invasive analysis. Using Prompt Gamma Activation Analysis (PGAA, we can measure major chemical components and some key trace elements of stone artefacts with adequate accuracy to successfully determine provenance of obsidian. Recent methodological development also facilitated the study of relatively large objects like the Nyírlugos cores. The cores were individually measured by PGAA. The results show that the cores originate from the Carpathian 1 sources, most probably the Viničky variety (C1b. The study of the hoard as a batch is an important contribution to the assessment of prehistoric trade and allows us to reconsider the so-called Carpathian, especially Carpathian 1 (Slovakian sources.

  11. Eruptive dynamics and hazards associated with obsidian bearing ignimbrites of the Geghama Volcanic Highland, Central Armenia: a textural insight

    Science.gov (United States)

    Matthews, Zoe; Manning, Christina J.

    2017-04-01

    The Geghama Volcanic highland in central Armenia is an ideal setting to study the young ( 750-25 ka [1]) volcanism that characterises the Lesser Caucasus region. The volcanism in the area is bimodal in composition: the eastern highlands are dominated by numerous monogenetic scoria cones, whilst the west shows more evolved volcanism centered on two obsidian bearing, polygenetic domes (Hatis and Gutanasar) [2]. Activity at Hatis and Gutanasar is thought to have spanned 550ka-200ka [3] and produced a range of products including obsidian flows, ignimbrites and basaltic scoria cones, consistent with long lived and complex magma storage systems. During a similar time period there is evidence for the presence of hominin groups in the surrounding region [3] and it is likely that at least some of the volcanic activity at Hatis and Gutanasar impacted on their distribution [4]. A better understanding of the eruptive behaviour of these volcanoes during this period could therefore shed light on the effect of volcanic activity on the dispersal of man through this period. Whilst large regional studies have striven to better understand the timing and source of volcanism in Armenia, there have been few detailed studies on single volcanoes. Obsidian is ubiquitous within the volcanic material of both Gutanasar and Hatis as lava flows, dome deposits and within ignimbrites. This study aims to better understand the eruptive history of Gutanasar, with specific focus upon the determination of the petrogenetic history of obsidian lenses observed within the ignimbrite deposits. Identification of these obsidians as the result of welding or in-situ melting will help constrain eruptive volumes and flow thickness, important for the reconstruction of palaeo-volcanic hazards. In order to interpret how this obsidian was deposited, macro textural analysis is combined with micro textural measurements of microlite crystals. Quantitative measurements of microlites in obsidian can provide significant

  12. Evaluating the applicability of portable-XRF for the characterization of Hokkaido Obsidian sources. A comparison with INAA, ICP-MS and EPMA

    International Nuclear Information System (INIS)

    Lynch, S.C.

    2016-01-01

    As a result of the limited application of portable X-ray fluorescence (pXRF) in archaeological research in Japan it is necessary to compare this technique to proven, laboratory-based, analytical techniques. In this study instrumental neutron activation analysis, inductively-coupled plasma mass spectrometry, and electron probe microanalysis are used to validate pXRF and determine the overall suitability of this technique for archaeological obsidian provenance studies in Hokkaido, northern Japan. Furthermore, the results of this study are compared to previously published data to assess reproducibility and compatibility. This study demonstrates the reliability of pXRF for the rapid characterization of Hokkaido obsidian while contributing to the ongoing evaluation of the applicability of 'off-the-shelf' pXRF to obsidian provenance research in archaeology. (author)

  13. The exploitation of obsidian in the Central Plateau of Santa Cruz, Argentina: Results from La María and Cerro Tres Tetas and a regional perspective

    Directory of Open Access Journals (Sweden)

    Manuel Enrique Cueto

    2016-09-01

    Results from this work strengthen the idea that the groups which lived in the Central Plateau knew about and exploited an obsidian source known as Pampa del Asador. A raise in the use of this raw material throughout time is recorded, reaching its peak in the late Holocene. We identified two different moments in the exploitation of obsidian at the regional level. During the final Pleistocene and early Holocene, obsidian would not have played a relevant role in the organization of technology. Production sequences indicate that tools probably were entered to the sites already manufactured. During the middle and late Holocene nodules and cores could have been brought into the sites. The strategies involved in their reduction are in broad terms similar to those implemented with local raw materials; there is no evidence that obsidian had more value in any way. On the other hand, it is also not possible to state that there was just an eventual exploitation of this raw material. We believe that obsidian was acquired during mobility circuits which enabled the contact between different groups.

  14. Dating by fission tracks in archaeology. 2. Characterization and dating of obsidian artefact

    International Nuclear Information System (INIS)

    Poupeau, G.; Zuleta, E.

    1984-01-01

    The ways of obsidian characterization presently used in archaeology are presented. The possibilities of the fission track method are more specially discussed, with two examples of works done in Japan and on any samples of andine America. (L.C.) [pt

  15. Obsidian dating by fission track method; Datacao de obsidianas com o metodo dos tracos de fissao

    Energy Technology Data Exchange (ETDEWEB)

    Araya, A M.O.

    1990-12-01

    The fission track method was employed to obtain the age of twelve obsidian sample from Ecuador. By using the plateau-age correction method, we obtained the true age of each sample and were able to identify four groups of ages in the studied area. Thereafter we studied the fading of fission tracks in two obsidian samples with different origins: Yanaurcu, Ecuador and Monte Arci, Italy. We constructed Arrhenius plots and calculated activation energies for both samples. The results from thermal annealing experiments were compared with theoretical curves obtained by integrating an equation proposed by Shukolyukov et al (1965). (author). 43 refs, 20 figs, 10 tabs.

  16. Provenance study of obsidian samples by using portable and conventional X ray fluorescence spectrometers. Performance comparison of both instrumentations

    International Nuclear Information System (INIS)

    Cristina Vazquez

    2012-01-01

    The potentiality of portable instrumentation lies on the possibility of the in situ determinations. Sampling, packaging and transport of samples from the site to the laboratory are avoided and the analysis becomes non destructive at all. However, detection limits for light elements are, in most cases, a limitation for quantification purposes. In this work a comparison between the results obtained with an X ray fluorescence spectrometer laboratory based and a portable instrument is performed. A set of 76 obsidian archaeological specimens from northwest Patagonia, Argentina was used to carry out the study. Samples were collected in the area of the middle and high basin of the Limay River. The analytical information obtained with both instrumentations was complemented with Principal Component Analysis in order to define groups and identify provenance sources. The information from both instruments allows arriving to the same conclusion about sample provenance and mobility of hunter-gatherer groups. Three groups of sources were identified in both cases matching with the geographical information. Also, same sets of outlier samples or not associated to these sources were found. Artifact samples were associated mainly to the closest sources, but some of them are related to sources located more than three hundred kilometers, evidencing the large mobility of the hunter-gatherers by the obsidian interchange. No significant differences between concentrations values obtained by laboratory based instrument and portable one were found. (author)

  17. Obsidian: alteration study under hydrothermal-like conditions for its assessment as a nuclear waste glass

    Energy Technology Data Exchange (ETDEWEB)

    Rania, Nishi; Shrivastava, J.P. [Department of Geology, University of Delhi, Delhi - 110007 (India); Bajpai, R.K. [BETDD, Nuclear Recycle Group, BARC, Mumbai - 400008 (India)

    2013-07-01

    Alteration experiments of obsidian (from Osham Hill, Gujarat, India) were performed under hydrothermal-like conditions. Neo-formed minerals were compared with naturally altered minerals to assess its performance. Altered specimens show partial to complete leaching of glass, where ionic release is of the order of Na>Si>K>Ca>Al = Mg>Mn>Ti. SEM-BSE images show distinct microstructures and mineral paragenesis of smectite, chlorite, nontronite, and illite inside and outside of the secondary layers - show retention of Si, Al, and Mg ions, fixation in the alteration products after their meager release to the solution. Secondary minerals-palagonite, chlorite, calcite, zeolite and white colored clays - formed after experiments largely correspond to altered obsidian in the natural environment since ∼ 65 Ma. (authors)

  18. Obsidian: alteration study under hydrothermal-like conditions for its assessment as a nuclear waste glass

    International Nuclear Information System (INIS)

    Rania, Nishi; Shrivastava, J.P.; Bajpai, R.K.

    2013-01-01

    Alteration experiments of obsidian (from Osham Hill, Gujarat, India) were performed under hydrothermal-like conditions. Neo-formed minerals were compared with naturally altered minerals to assess its performance. Altered specimens show partial to complete leaching of glass, where ionic release is of the order of Na>Si>K>Ca>Al = Mg>Mn>Ti. SEM-BSE images show distinct microstructures and mineral paragenesis of smectite, chlorite, nontronite, and illite inside and outside of the secondary layers - show retention of Si, Al, and Mg ions, fixation in the alteration products after their meager release to the solution. Secondary minerals-palagonite, chlorite, calcite, zeolite and white colored clays - formed after experiments largely correspond to altered obsidian in the natural environment since ∼ 65 Ma. (authors)

  19. Obsidian hydration rate for the klamath basin of california and Oregon.

    Science.gov (United States)

    Johnson, L

    1969-09-26

    A hydration rate for obsidian of 3.5(4) microns squared per 1000 radio-carbon years has been established at the Nightfire Island archeological site in northern California and provides a means to date other prehistoric Klamath Basin sites. The new rate follows the form of the hydration equation formulated by Friedman and helps to refute claims made for other hydration equations.

  20. Testing complex networks of interaction at the onset of the Near Eastern Neolithic using modelling of obsidian exchange.

    Science.gov (United States)

    Ibáñez, Juan José; Ortega, David; Campos, Daniel; Khalidi, Lamya; Méndez, Vicenç

    2015-06-06

    In this paper, we explore the conditions that led to the origins and development of the Near Eastern Neolithic using mathematical modelling of obsidian exchange. The analysis presented expands on previous research, which established that the down-the-line model could not explain long-distance obsidian distribution across the Near East during this period. Drawing from outcomes of new simulations and their comparison with archaeological data, we provide results that illuminate the presence of complex networks of interaction among the earliest farming societies. We explore a network prototype of obsidian exchange with distant links which replicates the long-distance movement of ideas, goods and people during the Early Neolithic. Our results support the idea that during the first (Pre-Pottery Neolithic A) and second (Pre-Pottery Neolithic B) phases of the Early Neolithic, the complexity of obsidian exchange networks gradually increased. We propose then a refined model (the optimized distant link model) whereby long-distance exchange was largely operated by certain interconnected villages, resulting in the appearance of a relatively homogeneous Neolithic cultural sphere. We hypothesize that the appearance of complex interaction and exchange networks reduced risks of isolation caused by restricted mobility as groups settled and argue that these networks partially triggered and were crucial for the success of the Neolithic Revolution. Communities became highly dynamic through the sharing of experiences and objects, while the networks that developed acted as a repository of innovations, limiting the risk of involution. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  1. The obsidian from Quiron (Salta Province, Argentina): a new reference glass for fission-track dating

    Energy Technology Data Exchange (ETDEWEB)

    Bigazzi, G. [Istituto di Geoscienze e Georisorse, C.N.R., Area della Ricerca di Pisa, V.G. Moruzzi, 1, 56124 Pisa (Italy)]. E-mail: g.bigazzi@igg.cnr.it; Laurenzi, M.A. [Istituto di Geoscienze e Georisorse, C.N.R., Area della Ricerca di Pisa, V.G. Moruzzi, 1, 56124 Pisa (Italy); Viramonte, J.G. [Instituto Geonorte, Universidad Nacional de Salta and Conicet, Buenos Aires 177, 4400 Salta (Argentina)

    2005-12-01

    In the course of a geochronological study of the volcanic activity in the Andean Cordillera in northern Argentina, we have found in the El Quevar volcanic complex (24 deg. 19{sup '}S/66 deg. 43{sup '}W,6180m) a phenocryst poor obsidian (Quiron obsidian) showing an unusually high spontaneous track density. Defects which might produce 'spurious' tracks are virtually absent. Application of fission-track dating using an absolute approach, based on the IRMM-540 standard glass for neutron fluence measurements, yielded an apparent age of 7.27+/-0.29Ma(1{sigma}) and a plateau age of 8.99+/-0.31Ma(1{sigma}). A {sup 40}Ar-{sup 39}Ar isochron age on biotite of 8.61+/-0.04Ma(1{sigma}) was already available for the Quiron rhyolite. We determined further {sup 40}Ar-{sup 39}Ar ages on several chips of the glass itself using two analytical approaches: total fusion with a focussed laser beam (LTFA) and a step-heating approach using a de-focussed laser beam (LSHA). We have obtained a weighted average of 8.77+/-0.09Ma, an isochron age of 8.71+/-0.12Ma and an integrated age of 8.77+/-0.09Ma for LTF analyses, and a w.a. of 8.75+/-0.09Ma, an iso.a. of 8.77+/-0.09Ma and an int.a. of 8.77+/-0.09Ma for LSH analyses (all age errors are 2{sigma}). The Quiron obsidian is very easy to analyse for its high spontaneous track density and because microlites which might produce spurious tracks are very rare. Independent reference {sup 40}Ar-{sup 39}Ar ages determined in different laboratories are available. For these reasons we believe that this glass may be very useful for testing fission-track system calibrations and apparent age correction procedures. Splits of obsidian Quiron will be distributed upon request to colleagues who intend to test it.

  2. Trace element characterisation of New Zealand obsidian using neutron activation analysis

    International Nuclear Information System (INIS)

    Chidgey, R.Y.

    1982-01-01

    The aim of this study was to assess the suitability of neutron activation data for characterising New Zealand obsidian through the application of multivariate statistics. The trace element concentrations were corrected for flux variation. NAA has the advantage of permitting measurements of concentrations of many elements to a sensitivity of less than 1 ppm. Furthermore, effects caused by weathering or mineral inclusions will not bias the measurements

  3. Obsidian Pyroclasts: Where Do They Come From and What Can They Tell Us?

    Science.gov (United States)

    Watkins, J. M.; Gardner, J. E.; Befus, K.

    2016-12-01

    Models for how volcanic gases behave during volcanic eruptions are constructed from measurements of volatiles (δD, H2O and CO2) in melt that has been quenched to glass. Volatile measurements on obsidian pyroclasts from Mono Craters, California, have been central to the development of open- versus closed-system and equilibrium versus non-equilibrium degassing models, and these models have been applied to the interpretation of volatile data from volcanic centers worldwide. Even for the well-studied Mono Craters system, however, there are several different degassing models that are compatible with existing data, and the origin of the vesicle-poor obsidian pyroclasts (upon which the degassing models have been built) remains ambiguous. To better establish the link between the volatiles in the pyroclasts and volcanic eruption processes, we combine textural analysis with area maps of CO2 and H2O. We show that obsidian pyroclasts are heterogeneous with respect to dissolved CO2 and H2O, and that many clasts have multiple textural and chemical domains that are sutured together. The observations suggest that clasts are assembled from non-equilibrated juvenile melt and ash during repeated melt fracturing and healing, ash sintering, and shearing along conduit margins. Melt fracturing promotes gas extraction from magma, whereas healing promotes gas resorption and glass densification. Some of the clasts have bands or patches of elevated CO2 associated with cuspate vesicles, which are evidence for CO2-rich vapor fluxing through the magmatic system. Collectively, the data support a model of open-system, non-equilibrium degassing with intermittent regassing caused by increases in pressure and exposure to different vapor compositions.

  4. Provenance studies of obsidians from Neolithic contexts in Southern Italy by IBA (Ion Beam Analysis) methods

    International Nuclear Information System (INIS)

    Quarta, Gianluca; Maruccio, Lucio; Calcagnile, Lucio

    2011-01-01

    Obsidian samples recovered in archaeological contexts in Southern Italy were analysed by PIXE (Particle Induced X-ray Emission) and PIGE (Particle Induced Gamma Ray Emission) for the quantitative determination of both major and trace elements composition. The archaeological contexts were absolutely dated to the 5th millennium BC by mean of AMS (Accelerator Mass Spectrometry) radiocarbon dating analyses carried out on associated organic materials such as charcoal and human bones. The comparison of the compositional results obtained for the analysed samples with published data available for the known obsidian sources in the Mediterranean allowed to identify the sources of the raw material, giving an important contribution to the reconstruction of the ancient trade and exchange routes in Southern Italy prehistory.

  5. The earliest long-distance obsidian transport: Evidence from the ∼200 ka Middle Stone Age Sibilo School Road Site, Baringo, Kenya.

    Science.gov (United States)

    Blegen, Nick

    2017-02-01

    This study presents the earliest evidence of long-distance obsidian transport at the ∼200 ka Sibilo School Road Site (SSRS), an early Middle Stone Age site in the Kapthurin Formation, Kenya. The later Middle Pleistocene of East Africa (130-400 ka) spans significant and interrelated behavioral and biological changes in human evolution including the first appearance of Homo sapiens. Despite the importance of the later Middle Pleistocene, there are relatively few archaeological sites in well-dated contexts (n obsidian transport, important for investigating expansion of intergroup interactions in hominin evolution, is rare from the Middle Pleistocene record of Africa. The SSRS offers a unique contribution to this small but growing dataset. Tephrostratigraphic analysis of tuffs encasing the SSRS provides a minimum age of ∼200 ka for the site. Levallois points and methods of core preparation demonstrate characteristic Middle Stone Age lithic technologies present at the SSRS. A significant portion (43%) of the lithic assemblage is obsidian. The SSRS obsidian comes from three different sources located at distances of 25 km, 140 km and 166 km from the site. The majority of obsidian derives from the farthest source, 166 km to the south of the site. The SSRS thus provides important new evidence that long-distance raw material transport, and the expansion of hominin intergroup interactions that this entails, was a significant feature of hominin behavior ∼200 ka, the time of the first appearance of H. sapiens, and ∼150,000 years before similar behaviors were previously documented in the region. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Determination of the provenance of obsidian samples collected in the archaeological site of San Miguel Ixtapan, Mexico State, Mexico by means of neutron activation analysis

    International Nuclear Information System (INIS)

    Almazan-Torres, M.G.; Aguirre-Martinez, P.I.

    2004-01-01

    Obsidian samples from San Miguel Ixtapan Mexico State, Mexico were analyzed by means of neutron activation. Statistical treatments such as bivariate, cluster and principal-components analyses were applied to the data set. Obsidians were identified as coming from three important sources: Sierra of Pachuca in the state of Hidalgo, Zinap uaro and Zin aro-Varal in the state of Michoacan. (author)

  7. Obsidian ages from Ecuador by the fission track dating

    International Nuclear Information System (INIS)

    Osorio, A.M.; Hadler, J.C.; Bigazzi, G.; Norelli, P.; Coltelli, M.; Salazar, E.

    1991-01-01

    Fission track dating was applied in order to study obsidian samples originated from Mullumica and Callejones flows, Oyacachi, Ecuador. Preliminary data show that the ratio between the mean diameter os spontaneous and induced tracks is about 0.9, an indication that the analysed samples were submitted to small fading during their geological histories. Ages were obtained around 0.2 x 10 6 a, in agreement with Miller and Wagners's results. Ages ranging from 0.17 x 10 6 a up to 0.23 x 10 6 a were obtained correcting the apparent ages by means of the plateau method. (author)

  8. Obsidian Studies in the Prehistoric Central Mediterranean: After 50 Years, What Have We Learned and What Still Needs to Be Done?

    Directory of Open Access Journals (Sweden)

    Tykot Robert H.

    2017-10-01

    Full Text Available Obsidian sourcing studies have been conducted in the central Mediterranean for more than 50 years. Detailed studies have been done on the geological sources on four Italian islands, and many analytical methods have been used to successfully distinguish between them. The ability to conduct analyses using those minimally (LA-ICP-MS or totally (XRF, pXRF non-destructive to artifacts has led to >10,000 analyses just in the last decade. Along with the ability to assign artifacts to specific geological subsources, and an increased number of studies of techno-typology, this has allowed interpretations to be made about source access and territorial control, craft specialization and the chaîne opératoire, as well as the modes, frequency, and directions of movement and how that varied spacially and temporally. Obsidian especially from Lipari and from Monte Arci in Sardinia traveled hundreds of kilometers on a regular basis starting in the Early Neolithic. By the Late Neolithic, in some areas there was selection of specific obsidian sources and subsources, and differences in production methods and tool typology. Obsidian distribution and usage in the central Mediterranean continued over four-and-one-half millennia, in many areas well into the Bronze Age. There is much more still to do integrating these different studies, especially use-wear studies, along with those of lithic and other materials that also played a role in prehistoric transport and trade systems.

  9. Origin identification for Cantona, Puebla, obsidians by the analysis method of neutron activation (NAA); Identificacion de procedencia para obsidianas de Cantona, Puebla, por el metodo de analisis por activacion neutronica (AAN)

    Energy Technology Data Exchange (ETDEWEB)

    Tellez N, A. L.

    2013-07-01

    There are tests that most of the obsidian worked in the workshops of Cantona, Puebla, is coming from the mineral deposits of Oyameles-Zaragoza, but also has been detected obsidian that macroscopically belongs to other mineral deposits. The present work has as purpose to determine the provenance of an obsidian sample obtained in the Cantona Site to know if there was the presence of obsidian of other mineral deposits. For the study the neutron activation analysis was used to identify the presence of other deposits. An explanation on the treatment to the selected pieces is included, the preparation of the same ones for its irradiation in the nuclear reactor, the counting and statistical study of the results. Finally the results of the selected samples are presented, indicating their origin places, that time comes and the interpretation of the results is given. (Author)

  10. Sources of some obsidian flakes from a Paleoindian site in Guatemala

    International Nuclear Information System (INIS)

    Stross, F.H.; Asaro, F.; Michel, H.V.; Gruhn, R.

    1977-01-01

    Neutron activation analysis was used to determine the chemical composition of sources of obsidian artifacts from the Paleoindian site of Los Tapiales in Guatemala with an occupation date of around 10,700 radiocarbon years ago. Three different sources were detected, all between 50 and 75 km from Los Tapiales. The predominant source represented in our ten samples was in the Rio Pixcaya area, and another was in the Tajumulco area. A third source, identified by comparison with other work, appears to be in the area of San Bartolome Milpas Altas

  11. 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

  12. The path of obsidian at the Tajin region. Origin analysis through Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Cruz J, R.L.

    2000-01-01

    The task of contemporary archaeology is extended every day; new techniques and new instruments have been incorporating to those tools which the archaeologist has in order to achieve a better approach to his study object. The archaeology had been exploring in the physical chemical sciences with the purpose to obtain information beyond the traditional methodologies and so obtaining more and best data. The sudden advance in the knowledge of the basic particles which make up the matter can be applied to these archaeological studies too. Archaeology takes part of the new possibilities which nuclear physics offers in the study of materials such as ceramics, clays, metal alloys, native metals and practically some lithological source. In Latin America the neutron activation analysis was used first for the characterization and determination of the ceramics origin. Some regions have been better studied from the point of view of obsidian exploitation and consumption, such is the case of El Tajin and Oaxaca region in Mexico. (Author)

  13. Systems of Interaction between the First Sedentary Villages in the Near East Exposed Using Agent-Based Modelling of Obsidian Exchange

    Directory of Open Access Journals (Sweden)

    David Ortega

    2016-03-01

    Full Text Available In the Near East, nomadic hunter-gatherer societies became sedentary farmers for the first time during the transition into the Neolithic. Sedentary life presented a risk of isolation for Neolithic groups. As fluid intergroup interactions are crucial for the sharing of information, resources and genes, Neolithic villages developed a network of contacts. In this paper we study obsidian exchange between Neolithic villages in order to characterize this network of interaction. Using agent-based modelling and elements taken from complex network theory, we model obsidian exchange and compare results with archaeological data. We demonstrate that complex networks of interaction were established at the outset of the Neolithic and hypothesize that the existence of these complex networks was a necessary condition for the success and spread of a new way of living.

  14. Juvenile pumice and pyroclastic obsidian reveal the eruptive conditions necessary for the stability of Plinian eruption of rhyolitic magma

    Science.gov (United States)

    Giachetti, T.; Shea, T.; Gonnermann, H. M.; McCann, K. A.; Hoxsie, E. C.

    2016-12-01

    Significant explosive activity generally precedes or coexists with the large effusion of rhyolitic lava (e.g., Mono Craters; Medicine Lake Volcano; Newberry; Chaitén; Cordón Caulle). Such explosive-to-effusive transitions and, ultimately, cessation of activity are commonly explained by the overall waning magma chamber pressure accompanying magma withdrawal, albeit modulated by magma outgassing. The tephra deposits of such explosive-to-effusive eruptions record the character of the transition - abrupt or gradual - as well as potential changes in eruptive conditions, such as magma composition, volatiles content, mass discharge rate, conduit size, magma outgassing. Results will be presented from a detailed study of both the gas-rich (pumice) and gas-poor (obsidian) juvenile pyroclasts produced during the Plinian phase of the 1060 CE Glass Mountain eruption of Medicine Lake Volcano, California. In the proximal deposits, a multitude of pumice-rich sections separated by layers rich in dense clasts suggests a pulsatory behavior of the explosive phase. Density measurements on 2,600 pumices show that the intermediate, most voluminous deposits have a near constant median porosity of 65%. However, rapid increase in porosity to 75-80% is observed at both the bottom and the top of the fallout deposits, suggestive of rapid variations in magma degassing. In contrast, a water content of pyroclastic obsidians of approximately 0.6 wt% does remain constant throughout the eruption, suggesting that the pyroclastic obsidians degassed up to a constant pressure of a few megapascals. Numerical modeling of eruptive magma ascent and degassing is used to provide constraints on eruption conditions.

  15. Obsidian sourcing studies in Papua New Guinea using PIXE-PIGME analysis

    Energy Technology Data Exchange (ETDEWEB)

    Summerhayes, G R; Gosden, C [La Trobe Univ., Bundoora, VIC (Australia); Bird, R; Hotchkis, M [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Specht, J; Torrence, R; Fullaga, R [Australian Museum, Sydney, NSW (Australia). Div. of Anthropology

    1994-12-31

    Over 100 obsidian samples were analysed using PIXE-PIGME in 1990. These samples were collected during intensive surveys of the source areas around Talasea, Garua Island, and the Mopir area in 1988, 1989 and 1990. A ratio combination of 9 elements were used to separate out groups as per previous studies: F/Na, Al/Na, K/Fe, Ca/Fe, Mn/Fe, Rb/Fe, Y/Zr, Sr/Fe and Zr/Fe. In spite of variations in major elements, the close agreement between results for minor and trace elements concentrations in artefacts and known source material indicates that the provenance of each artefact can be reliably determined. This conclusion provides important validation of the use of ion beam analysis in artefact characterisation. ills.

  16. Obsidian sourcing studies in Papua New Guinea using PIXE-PIGME analysis

    International Nuclear Information System (INIS)

    Summerhayes, G.R.; Gosden, C.; Bird, R.; Hotchkis, M.; Specht, J.; Torrence, R.; Fullaga, R.

    1993-01-01

    Over 100 obsidian samples were analysed using PIXE-PIGME in 1990. These samples were collected during intensive surveys of the source areas around Talasea, Garua Island, and the Mopir area in 1988, 1989 and 1990. A ratio combination of 9 elements were used to separate out groups as per previous studies: F/Na, Al/Na, K/Fe, Ca/Fe, Mn/Fe, Rb/Fe, Y/Zr, Sr/Fe and Zr/Fe. In spite of variations in major elements, the close agreement between results for minor and trace elements concentrations in artefacts and known source material indicates that the provenance of each artefact can be reliably determined. This conclusion provides important validation of the use of ion beam analysis in artefact characterisation. ills

  17. Obsidian sourcing studies in Papua New Guinea using PIXE-PIGME analysis

    Energy Technology Data Exchange (ETDEWEB)

    Summerhayes, G.R.; Gosden, C. [La Trobe Univ., Bundoora, VIC (Australia); Bird, R.; Hotchkis, M. [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Specht, J.; Torrence, R.; Fullaga, R. [Australian Museum, Sydney, NSW (Australia). Div. of Anthropology

    1993-12-31

    Over 100 obsidian samples were analysed using PIXE-PIGME in 1990. These samples were collected during intensive surveys of the source areas around Talasea, Garua Island, and the Mopir area in 1988, 1989 and 1990. A ratio combination of 9 elements were used to separate out groups as per previous studies: F/Na, Al/Na, K/Fe, Ca/Fe, Mn/Fe, Rb/Fe, Y/Zr, Sr/Fe and Zr/Fe. In spite of variations in major elements, the close agreement between results for minor and trace elements concentrations in artefacts and known source material indicates that the provenance of each artefact can be reliably determined. This conclusion provides important validation of the use of ion beam analysis in artefact characterisation. ills.

  18. Characterization of obsidian devices come from San Miguel Ixtapan, Estado de Mexico by Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Almazan T, M.G.; Jimenez R, M.; Monroy G, F.; Tenorio C, D.

    2002-01-01

    The Neutron Activation Analysis (NAA) is an efficient multielemental technique for determination of elements in low concentration (ppm), what has been result useful in the study of origin of archaeological material. In this work that technique was used for characterizing obsidian devices coming from the San Miguel Ixtapan site, Estado de Mexico and it was found that these come from three important beds which are: Sierra de Pachuca, Hidalgo, Zinapecuaro and Zinaparo-Varal in the Michoacan state. (Author)

  19. Measuring effusion rates of obsidian lava flows by means of satellite thermal data

    Science.gov (United States)

    Coppola, D.; Laiolo, M.; Franchi, A.; Massimetti, F.; Cigolini, C.; Lara, L. E.

    2017-11-01

    Space-based thermal data are increasingly used for monitoring effusive eruptions, especially for calculating lava discharge rates and forecasting hazards related to basaltic lava flows. The application of this methodology to silicic, more viscous lava bodies (such as obsidian lava flows) is much less frequent, with only few examples documented in the last decades. The 2011-2012 eruption of Cordón Caulle volcano (Chile) produced a voluminous obsidian lava flow ( 0.6 km3) and offers an exceptional opportunity to analyze the relationship between heat and volumetric flux for such type of viscous lava bodies. Based on a retrospective analysis of MODIS infrared data (MIROVA system), we found that the energy radiated by the active lava flow is robustly correlated with the erupted lava volume, measured independently. We found that after a transient time of about 15 days, the coefficient of proportionality between radiant and volumetric flux becomes almost steady, and stabilizes around a value of 5 × 106 J m- 3. This coefficient (i.e. radiant density) is much lower than those found for basalts ( 1 × 108 J m- 3) and likely reflects the appropriate spreading and cooling properties of the highly-insulated, viscous flows. The effusion rates trend inferred from MODIS data correlates well with the tremor amplitude and with the plume elevation recorded throughout the eruption, thus suggesting a link between the effusive and the coeval explosive activity. Modelling of the eruptive trend indicates that the Cordón Caulle eruption occurred in two stages, either incompletely draining a single magma reservoir or more probably tapping multiple interconnected magmatic compartments.

  20. The fission-track analysis: An alternative technique for provenance studies of prehistoric obsidian artefacts

    CERN Document Server

    Bellot-Gurlet, L; Dorighel, O; Oddone, M; Poupeau, G; Yegingil, Z

    1999-01-01

    Comparison of fission-track parameters - age and track densities - is an alternative tool for correlating obsidian artefacts with their potential natural sources. This method was applied by different fission-track groups in various regions and results were compared with those obtained using the more popular provenance identification techniques based on chemical composition studies. Hundreds of analyses prove that fission-track dating is a complementary technique which turns out to be very useful, specially when the chemical composition does not fully discriminate different sources. Archaeologically significant results were obtained applying the fission-track analysis in various regions of earth.

  1. The fission-track analysis: An alternative technique for provenance studies of prehistoric obsidian artefacts

    International Nuclear Information System (INIS)

    Bellot-Gurlet, L.; Bigazzi, G.; Dorighel, O.; Oddone, M.; Poupeau, G.; Yegingil, Z.

    1999-01-01

    Comparison of fission-track parameters - age and track densities - is an alternative tool for correlating obsidian artefacts with their potential natural sources. This method was applied by different fission-track groups in various regions and results were compared with those obtained using the more popular provenance identification techniques based on chemical composition studies. Hundreds of analyses prove that fission-track dating is a complementary technique which turns out to be very useful, specially when the chemical composition does not fully discriminate different sources. Archaeologically significant results were obtained applying the fission-track analysis in various regions of earth

  2. Modelling obsidian trade routes during late Neolithic in the south-east Banat region of Vršac using GIS

    Directory of Open Access Journals (Sweden)

    Marić Miroslav

    2015-01-01

    Full Text Available The aim of this paper is to reconstruct the possible trajectory of the movement of the obsidian that was brought to the region of present day Vršac from Carpathian 1 and Carpathian 2 sources, located between Košice and Miškolc (the present day border area between Hungary and Slovakia. This objective has been fulfilled using computer aided modelling performed within the constraints of geographic information system software based on the physical characteristics of the terrain and the reconstruction of paleoenvironmental and paleoclimatic conditions in the period of the late Neolithic. The second largest obsidian collection in the territory of Vinča culture originates from the site of Potporanj, south of Vršac. The abundance of finds indicates the importance this region had in the distribution of this resource during late Neolithic. In the paper the modelling of two different possibilities of land based distribution from the flow of the river Tisza are shown; the first from Perlez/Opovo (western route and the other from Mureє (northern route, i.e. present day Arad and Timiєoara. The modelled results indicate the existence of a settlement patterning close to the modelled pathways in the period of Vinča culture. [Projekat Ministarstva nauke Republike Srbije, br. 177012: Society, Culture and Communications in the Balkans in Proto - and Early History

  3. Producing adornment: Evidence of different levels of expertise in the production of obsidian items of adornment at two late Neolithic communities in northern Mesopotamia

    Directory of Open Access Journals (Sweden)

    Elizabeth Healey

    2014-09-01

    Full Text Available In the Near East obsidian is of particular interest to archaeologists because it is an exotic material and best known for is use in tool manufacture, but it is also occasionally used to make items of personal adornment. Some of these items are very highly finished, while others appear much more rudimentary though it is by no means obvious why this should be. Here we will review such artefacts at two contemporary late Neolithic communities, Domuztepe in SE Anatolia and Tell Arpachiyah in northern Iraq. Both have seemingly unusually high numbers of such objects as well as evidence for obsidian tool production on site. At Domuztepe some objects are highly finished while others appear much more ad hoc. At Arpachiyah on the other hand, the objects appear very similar to each other so as to seem standardised or at least the product of a single workshop. Our main aim in this paper is to try to unravel the evidence needed to determine whether they were produced on site, or whether they were acquired as finished objects (or both.

  4. PXRF Determination of the Obsidian Industry from the S–F Area of Piani della Corona EBA Settlement (Bagnara Calabra–RC, South Italy

    Directory of Open Access Journals (Sweden)

    Marino Sara

    2017-10-01

    Full Text Available Archaeological excavations in the S-F area of Piani della Corona settlement have affected a portion of 2200 m2 of a large plateau (490 m asl. The researches, conducted between 2007 and 2008 by the Superintendence of the Museo Preistorico Etnografico “L. Pigorini” with the Archaeological Superintendence of Calabria, have revealed traces of a large village from the EBA. Before settling in the EBA, human groups belonging Recent Neolithic frequented the plateau. Two burials located near the Bronze Age ditch belong to this period, and there are also sporadic ceramic fragments recovered from the huts. The importance of Piani della Corona is mainly due to its strategic location, serving as a bridge between Calabria, Sicily and the Aeolian Islands, as proven by the archaeological record. A very important role was provided by the obsidian industry, dated after the most distinctive archaeological ceramics class, to the EBA. Out of the 238 obsidian tools found in the S-F area (blades, cores and amorphous splinters, 88 artifacts were analyzed by pXRF. Their chemical determination made it possible to clarify the procurement dynamics and exchange routes with the Aeolian Islands for the EBA, integrating new data in an on-going research.

  5. The characterisation of Melanesian obsidian sources and artefacts using the proton induced gamma-ray emission (PIGME) technique

    International Nuclear Information System (INIS)

    Bird, J.R.; Ambrose, W.R.; Russell, L.H.; Scott, M.D.

    1981-09-01

    Proton induced gamma-ray emission (PIGME) has been used to determine F, Na and Al concentrations in obsidian from known locations in Melanesia and to relate artefacts from this region to such sources. The PIGME technique is a fast, non-destructive, and accurate method for determining these three elements with essentially no special sample preparation. The measuring technique is described and results are listed for sources, chiefly in the Papua New Guinea region. Their classification is discussed in terms of groups which are distinguishable by the PIGME method. Over 700 artefact results are listed; these show the occurrence of an additional group that is not geographically identified

  6. Analysis of obsidians by PIXE technique

    International Nuclear Information System (INIS)

    Nuncio Q, A.E.

    1998-01-01

    This work presents the characterization of obsydian samples from different mineral sites in Mexico, undertaken by an Ion Beam Analysis: PIXE (Proton Induced X-ray Emission). As part of an intensive investigation of obsidian in Mesoamerica by anthropologists from Mexico National Institute of Anthropology and History, 818 samples were collected from different volcanic sources in central Mexico for the purpose of establishing a data bank of element concentrations of each source. Part of this collection was analyzed by Neutron activation analysis and most of the important elements concentrations reported. In this work, a non-destructive IBA technique (PIXE) are used to analyze obsydian samples. The application of this technique were carried out at laboratories of the ININ Nuclear Center facilities. The samples consisted of of obsydians from ten different volcanic sources. This pieces were mounted on a sample holder designed for the purpose of exposing each sample to the proton beam. This PIXE analysis was carried out with an ET Tandem Accelerator at the ININ. X-ray spectrometry was carried out with an external beam facility employing a Si(Li) detector set at 52.5 degrees in relation to the target normal (parallel to the beam direction) and 4.2 cm away from the target center. A filter was set in front of the detector, to determine the best attenuation conditions to obtain most of the elements, taking into account that X-ray spectra from obsydians are dominated by intense major elements lines. Thus, a 28 μ m- thick aluminium foil absorber was selected and used to reduce the intensity of the major lines as well as pile-up effects. The mean proton energy was 2.62 MeV, and the beam profile was about 4 mm in diameter. As results were founded elemental concentrations of a set of samples from ten different sources: Altotonga (Veracruz), Penjamo (Guanajuato), Otumba (Mexico), Zinapecuaro (Michoacan), Ucareo (Michoacan), Tres Cabezas (Puebla), Sierra Navajas (Hidalgo), Zaragoza

  7. Paleointensities on 8 ka obsidian from Mayor Island, New Zealand

    Directory of Open Access Journals (Sweden)

    A. Ferk

    2011-11-01

    Full Text Available The 8 ka BP (6050 BCE pantelleritic obsidian flow on Mayor Island, Bay of Plenty, New Zealand, has been investigated using 30 samples from two sites. Due to a very high paramagnetic/ferromagnetic ratio, it was not possible to determine the remanence carriers. This is despite the fact that the samples were studied intensively at low, room, and high temperatures. We infer that a stable remanence within the samples is carried by single- or close to single-domain particles. Experiments to determine the anisotropy of thermoremanence tensor and the dependency on cooling rate were hampered due to alteration resulting from the repeated heating of the samples to temperatures just below the glass transition. Nonetheless, a well-defined mean paleointensity of 57.0 ± 1.0 μT, based on individual high quality paleointensity determinations, was obtained. This field value compares very well to a paleointensity of 58.1 ± 2.9 μT, which Tanaka et al. (2009 obtained for 5500 BCE at a site 100 km distant. Agreement with geomagnetic field models, however, is poor. Thus, gathering more high-quality paleointensity data for the Pacific region and for the southern hemisphere in general to better constrain global field models is very important.

  8. Community analysis of plant biomass-degrading microorganisms from Obsidian Pool, Yellowstone National Park.

    Science.gov (United States)

    Vishnivetskaya, Tatiana A; Hamilton-Brehm, Scott D; Podar, Mircea; Mosher, Jennifer J; Palumbo, Anthony V; Phelps, Tommy J; Keller, Martin; Elkins, James G

    2015-02-01

    The conversion of lignocellulosic biomass into biofuels can potentially be improved by employing robust microorganisms and enzymes that efficiently deconstruct plant polysaccharides at elevated temperatures. Many of the geothermal features of Yellowstone National Park (YNP) are surrounded by vegetation providing a source of allochthonic material to support heterotrophic microbial communities adapted to utilize plant biomass as a primary carbon and energy source. In this study, a well-known hot spring environment, Obsidian Pool (OBP), was examined for potential biomass-active microorganisms using cultivation-independent and enrichment techniques. Analysis of 33,684 archaeal and 43,784 bacterial quality-filtered 16S rRNA gene pyrosequences revealed that archaeal diversity in the main pool was higher than bacterial; however, in the vegetated area, overall bacterial diversity was significantly higher. Of notable interest was a flooded depression adjacent to OBP supporting a stand of Juncus tweedyi, a heat-tolerant rush commonly found growing near geothermal features in YNP. The microbial community from heated sediments surrounding the plants was enriched in members of the Firmicutes including potentially (hemi)cellulolytic bacteria from the genera Clostridium, Anaerobacter, Caloramator, Caldicellulosiruptor, and Thermoanaerobacter. Enrichment cultures containing model and real biomass substrates were established at a wide range of temperatures (55-85 °C). Microbial activity was observed up to 80 °C on all substrates including Avicel, xylan, switchgrass, and Populus sp. Independent of substrate, Caloramator was enriched at lower (65 °C) temperatures.

  9. COERCIVITY AND VECTOR MAGNETIZATION ANALYSIS OF OBSIDIAN SAMPLES FROM THE TRANS-MEXICAN VOLCANIC BELT (Coercitividad y análisis de magnetización vectorial de muestras de obsidianas de la faja volcánica transmexicana

    Directory of Open Access Journals (Sweden)

    Jaime Urrutia-Fucugauchi

    2017-09-01

    Full Text Available This note presents initial results of a paleomagnetic study of obsidian from twenty localities in the eastern, central and western sectors of the Trans-Mexican volcanic belt in central Mexico. We focus on the coercivity and vector composition of the remanent magnetization, which are critical for paleodirectional and paleointensity studies. Alternating field demagnetization shows that obsidians carry single and two-component magnetizations residing in low- and high-coercivity magnetic minerals, with discrete and overlapping coercivity spectra. Magnetic minerals are likely iron-titanium oxides with fine-grain sizes characterized by pseudo-single domain states. ESPAÑOL: Se presentan los resultados preliminares del estudio de obsidianas de veinte localidades en los sectores este, central y oeste de la faja volcánica transmexicana. Los análisis se concentran en la coercitividad y la composición vectorial de la magnetización remanente, que son propiedades claves para evaluar los registros de direcciones e intensidades. La desmagnetización por campos alternos revela la presencia de magnetizaciones de una y dos componentes, que residen en minerales con baja y alta coercitividad con espectros que traslapan y discretos. Los minerales magnéticos son óxidos de hierro-titanio con grano fino y estados de dominio seudosencillo.

  10. Geochemical study of two obsidian production centers in the Prehistory of Tenerife: El Tabonal de los Guanches (Icod de los Vinos and el Tabonal Negro (Las Cañadas

    Directory of Open Access Journals (Sweden)

    Hernández Gómez, Cristo M.

    2008-12-01

    Full Text Available The obsidian production is one of the work processes that allow a good characterization of the Guanches, first inhabitants of Tenerife (Canary Islands. On this occasion, addresses the geochemical study of the volcanic flows where the main obsidian sources of the Aboriginal of Tenerife are located: The Tabonal de Los Guanches (Icod de Los Vinos and the Tabonal Negro, Mña. Blanca (Las Cañadas del Teide characterized as Production Centres. The aim is to establish the compositional differences between the two in order to trace the distribution of their lithic productions in the island territory and recognize the pattern of supply that was put into practice.

    La producción obsidiánica es uno de los procesos de trabajo que mejor permite la caracterización social de los guanches, primeros habitantes de Tenerife (Canarias. En esta ocasión se aborda el estudio geoquímico de las coladas en las que se ubican sus principales fuentes de aprovisionamiento de obsidiana: El Tabonal de Los Guanches (Icod de los Vinos y El Tabonal Negro en Mña. Blanca (Las Cañadas del Teide, consideradas desde el punto de vista arqueológico como Centros de Producción. El objetivo es establecer las diferencias composicionales entre ambas para poder rastrear la distribución de sus respectivas producciones líticas en el territorio insular y reconocer el modelo de suministro que se puso en práctica.

  11. Characterization of obsidian devices come from San Miguel Ixtapan, Estado de Mexico by Neutron Activation Analysis; Caracterizacion de artefactos de obsidiana provenientes de San Miguel Ixtapan, Estado de Mexico con Analisis por Activacion Neutronica

    Energy Technology Data Exchange (ETDEWEB)

    Almazan T, M.G.; Jimenez R, M.; Monroy G, F.; Tenorio C, D. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2002-07-01

    The Neutron Activation Analysis (NAA) is an efficient multielemental technique for determination of elements in low concentration (ppm), what has been result useful in the study of origin of archaeological material. In this work that technique was used for characterizing obsidian devices coming from the San Miguel Ixtapan site, Estado de Mexico and it was found that these come from three important beds which are: Sierra de Pachuca, Hidalgo, Zinapecuaro and Zinaparo-Varal in the Michoacan state. (Author)

  12. The scrapers of obsidian from Metztitlan, Hidalgo. Typology and tools function with the application of the Sem, PIXE and NAA techniques

    International Nuclear Information System (INIS)

    Elizalde R, S.V.; Mandujano A, C.

    2000-01-01

    In the last 50 years have been enormous changes and the archaeology has been benefited with the technology development, as computation, the advancements in nuclear physics, the electron microscopy, the particle accelerator and the DNA analysis. As first approach to studied material it was realized in cabinet the morphological and technological analysis to establish a typology and to know the manufacturer process of the scrapers (tool used for to scrape a cavity after cutting its lance-shaping leaves at the maguey core obtaining so the sap commonly named hydromel at the Hidalgo state region in Mexico). On the other hand the studies which carried out in the ININ consist in the functional analysis of use traces in scanning electron microscopy (Sem) and stereoscopic to know about the type of work which were addressed the scrapers. Also were carried out the Neutron Activation Analysis (NAA) and the Proton Induced X-ray Emission (PIXE) with the purpose to know the obsidian site which was supplied the Dominion population. (Author)

  13. El Parque Portal Bicentenario en Santiago de Chile / Portal Bicentennial Park in Santiago de Chile

    Directory of Open Access Journals (Sweden)

    Beach Lobos, Myriam;

    2007-06-01

    Full Text Available Se presenta los principios que orientaron el diseño del Parque Portal Bicentenario, un parque de 50 hás. que será el eje principal de la nueva urbanización “Ciudad Parque Bicentenario”, actualmente en construcción en los terrenos del ex aeropuerto de Los Cerrillos en Santiago de Chile.The following text was submitted to the Architecture Competition together with the project drawings. It presents the principles that leaded the design. The 123 acres park will be the main axis of a new urban development in Santiago “Ciudad Parque Bicentenario” at present under construction on the area occupied by the former Cerrillos Airport, Santiago de Chile.

  14. Stand structure and regeneration of harvested Araucaria araucana ...

    African Journals Online (AJOL)

    Stand structure and regeneration of harvested Araucaria araucana–Nothofagus stands in central Chile. Rafael M Navarro-Cerrillo, Fernando Olave, Francisco Moreno, Sergio de Miguel, Margarita Clemente ...

  15. Thermodesulfobacterium geofontis sp. nov., a hyperthermophilic, sulfate-reducing bacterium isolated from Obsidian Pool, Yellowstone National Park.

    Science.gov (United States)

    Hamilton-Brehm, Scott D; Gibson, Robert A; Green, Stefan J; Hopmans, Ellen C; Schouten, Stefan; van der Meer, Marcel T J; Shields, John P; Damsté, Jaap S S; Elkins, James G

    2013-03-01

    A novel sulfate-reducing bacterium designated OPF15(T) was isolated from Obsidian Pool, Yellowstone National Park, Wyoming. The phylogeny of 16S rRNA and functional genes (dsrAB) placed the organism within the family Thermodesulfobacteriaceae. The organism displayed hyperthermophilic temperature requirements for growth with a range of 70-90 °C and an optimum of 83 °C. Optimal pH was around 6.5-7.0 and the organism required the presence of H2 or formate as an electron donor and CO2 as a carbon source. Electron acceptors supporting growth included sulfate, thiosulfate, and elemental sulfur. Lactate, acetate, pyruvate, benzoate, oleic acid, and ethanol did not serve as electron donors. Membrane lipid analysis revealed diacyl glycerols and acyl/ether glycerols which ranged from C14:0 to C20:0. Alkyl chains present in acyl/ether and diether glycerol lipids ranged from C16:0 to C18:0. Straight, iso- and anteiso-configurations were found for all lipid types. The presence of OPF15(T) was also shown to increase cellulose consumption during co-cultivation with Caldicellulosiruptor obsidiansis, a fermentative, cellulolytic extreme thermophile isolated from the same environment. On the basis of phylogenetic, phenotypic, and structural analyses, Thermodesulfobacterium geofontis sp. nov. is proposed as a new species with OPF15(T) representing the type strain.

  16. Development of proton-induced x-ray emission techniques with application to multielement analyses of human autopsy tissues and obsidian artifacts

    International Nuclear Information System (INIS)

    Nielson, K.K.

    1975-01-01

    A method of trace element analysis using proton-induced x-ray emission (PIXE) techniques with energy dispersive x-ray detection methods is described. Data were processed using the computer program ANALEX. PIXE analysis methods were applied to the analysis of liver, spleen, aorta, kidney medulla, kidney cortex, abdominal fat, pancreas, and hair from autopsies of Pima Indians. Tissues were freeze dried and low temperature ashed before analysis. Concentrations were tabulated for K, Ca, Ti, Mn, Fe, Co, Ni, Cu, Zn, Pb, Se, Br, Rb, Sr, Cd, and Cs and examined for significant differences related to diabetes. Concentrations of Ca and Sr in aorta, Fe and Rb in spleen and Mn in liver had different patterns in diabetics than in nondiabetics. High Cs concentrations were also observed in the kidneys of two subjects who died of renal disorders. Analyses by atomic absorption and PIXE methods were compared. PIXE methods were also applied to elemental analysis of obsidian artifacts from Campeche, Mexico. Based on K, Ba, Mn, Fe, Rb, Sr and Zr concentrations, the artifacts were related to several Guatemalan sources. (Diss. Abstr. Int., B)

  17. Complete genome sequences of Geobacillus sp. Y412MC52, a xylan-degrading strain isolated from obsidian hot spring in Yellowstone National Park.

    Science.gov (United States)

    Brumm, Phillip; Land, Miriam L; Hauser, Loren J; Jeffries, Cynthia D; Chang, Yun-Juan; Mead, David A

    2015-01-01

    Geobacillus sp. Y412MC52 was isolated from Obsidian Hot Spring, Yellowstone National Park, Montana, USA under permit from the National Park Service. The genome was sequenced, assembled, and annotated by the DOE Joint Genome Institute and deposited at the NCBI in December 2011 (CP002835). Based on 16S rRNA genes and average nucleotide identity, Geobacillus sp. Y412MC52 and the related Geobacillus sp. Y412MC61 appear to be members of a new species of Geobacillus. The genome of Geobacillus sp. Y412MC52 consists of one circular chromosome of 3,628,883 bp, an average G + C content of 52 % and one circular plasmid of 45,057 bp and an average G + C content of 45 %. Y412MC52 possesses arabinan, arabinoglucuronoxylan, and aromatic acid degradation clusters for degradation of hemicellulose from biomass. Transport and utilization clusters are also present for other carbohydrates including starch, cellobiose, and α- and β-galactooligosaccharides.

  18. 77 FR 25739 - Notice of Inventory Completion: Fowler Museum at UCLA, Los Angeles, CA

    Science.gov (United States)

    2012-05-01

    ... objects are 1 awl, 1 bone tool, 2 obsidian biface fragments, 9 bags of obsidian debitage, 4 stone metate fragments, 4 bags of animal bone, 1 obsidian hydration sample, and 5 bags of organic flotation residue. The... artifacts and obsidian hydration dating. The Fowler Museum at UCLA has determined the human remains and...

  19. Experimental dehydration of natural obsidian and estimation of DH2O at low water contents

    Science.gov (United States)

    Jambon, A.; Zhang, Y.; Stolper, E. M.

    1992-01-01

    Water diffusion experiments were carried out by dehydrating rhyolitic obsidian from Valles Caldera (New Mexico, USA) at 510-980 degrees C. The starting glass wafers contained approximately 0.114 wt% total water, lower than any glasses previously investigated for water diffusion. Weight loss due to dehydration was measured as a function of experiment duration, which permits determination of mean bulk water diffusivity, mean Dw. These diffusivities are in the range of 2.6 to 18 X 10(-14) m2/s and can be fit with the following Arrhenius equation: ln mean Dw (m2/s) = -(25.10 +/- 1.29) - (46,480 +/- 11,400) (J/mol) / RT, except for two replicate runs at 510 degrees C which give mean Dw values much lower than that defined by the above equation. When interpreted according to a model of water speciation in which molecular H2O is the diffusing species with concentration-independent diffusivity while OH units do not contribute to the transport but react to provide H2O, the data (except for the 510 degrees C data) are in agreement with extrapolation from previous results and hence extend the previous data base and provide a test of the applicability of the model to very low water contents. Mean bulk water diffusivities are about two orders of magnitude less than molecular H2O diffusivities because the fraction of molecular H2O out of total water is very small at 0.114 wt% total water and less. The 510 degrees C experimental results can be interpreted as due to slow kinetics of OH to H2O interconversion at low temperatures.

  20. Caldicellulosiruptor obsidiansis sp. nov., an anaerobic, extremely thermophilic, cellulolytic bacterium isolated from Obsidian Pool, Yellowstone National Park.

    Science.gov (United States)

    Hamilton-Brehm, Scott D; Mosher, Jennifer J; Vishnivetskaya, Tatiana; Podar, Mircea; Carroll, Sue; Allman, Steve; Phelps, Tommy J; Keller, Martin; Elkins, James G

    2010-02-01

    A novel, obligately anaerobic, extremely thermophilic, cellulolytic bacterium, designated OB47(T), was isolated from Obsidian Pool, Yellowstone National Park, WY. The isolate was a nonmotile, non-spore-forming, Gram-positive rod approximately 2 microm long by 0.2 microm wide and grew at temperatures between 55 and 85 degrees C, with the optimum at 78 degrees C. The pH range for growth was 6.0 to 8.0, with values of near 7.0 being optimal. Growth on cellobiose produced the fastest specific growth rate at 0.75 h(-1). The organism also displayed fermentative growth on glucose, maltose, arabinose, fructose, starch, lactose, mannose, sucrose, galactose, xylose, arabinogalactan, Avicel, xylan, filter paper, processed cardboard, pectin, dilute acid-pretreated switchgrass, and Populus. OB47(T) was unable to grow on mannitol, fucose, lignin, Gelrite, acetate, glycerol, ribose, sorbitol, carboxymethylcellulose, and casein. Yeast extract stimulated growth, and thiosulfate, sulfate, nitrate, and sulfur were not reduced. Fermentation end products were mainly acetate, H2, and CO2, although lactate and ethanol were produced in 5-liter batch fermentations. The G+C content of the DNA was 35 mol%, and sequence analysis of the small subunit rRNA gene placed OB47(T) within the genus Caldicellulosiruptor. Based on its phylogenetic and phenotypic properties, the isolate is proposed to be designated Caldicellulosiruptor obsidiansis sp. nov. and OB47 is the type strain (ATCC BAA-2073).

  1. Caldicellulosiruptor obsidiansis sp. nov., an Anaerobic, Extremely Thermophilic, Cellulolytic Bacterium Isolated from Obsidian Pool, Yellowstone National Park▿

    Science.gov (United States)

    Hamilton-Brehm, Scott D.; Mosher, Jennifer J.; Vishnivetskaya, Tatiana; Podar, Mircea; Carroll, Sue; Allman, Steve; Phelps, Tommy J.; Keller, Martin; Elkins, James G.

    2010-01-01

    A novel, obligately anaerobic, extremely thermophilic, cellulolytic bacterium, designated OB47T, was isolated from Obsidian Pool, Yellowstone National Park, WY. The isolate was a nonmotile, non-spore-forming, Gram-positive rod approximately 2 μm long by 0.2 μm wide and grew at temperatures between 55 and 85°C, with the optimum at 78°C. The pH range for growth was 6.0 to 8.0, with values of near 7.0 being optimal. Growth on cellobiose produced the fastest specific growth rate at 0.75 h−1. The organism also displayed fermentative growth on glucose, maltose, arabinose, fructose, starch, lactose, mannose, sucrose, galactose, xylose, arabinogalactan, Avicel, xylan, filter paper, processed cardboard, pectin, dilute acid-pretreated switchgrass, and Populus. OB47T was unable to grow on mannitol, fucose, lignin, Gelrite, acetate, glycerol, ribose, sorbitol, carboxymethylcellulose, and casein. Yeast extract stimulated growth, and thiosulfate, sulfate, nitrate, and sulfur were not reduced. Fermentation end products were mainly acetate, H2, and CO2, although lactate and ethanol were produced in 5-liter batch fermentations. The G+C content of the DNA was 35 mol%, and sequence analysis of the small subunit rRNA gene placed OB47T within the genus Caldicellulosiruptor. Based on its phylogenetic and phenotypic properties, the isolate is proposed to be designated Caldicellulosiruptor obsidiansis sp. nov. and OB47 is the type strain (ATCC BAA-2073). PMID:20023107

  2. Uranium mobility during interaction of rhyolitic obsidian, perlite and felsite with alkaline carbonate solution: T = 120° C, P = 210 kg/cm2

    Science.gov (United States)

    Zielinski, Robert A.

    1979-01-01

    Well-characterized samples of rhyolitic obsidian, perlite and felsite from a single lava flow are leached of U by alkaline oxidizing solutions under open-system conditions. Pressure, temperature, flow rate and solution composition are held constant in order to evaluate the relative importance of differences in surface area and crystallinity. Under the experimental conditions U removal from crushed glassy samples proceeds by a mechanism of glass dissolution in which U and silica are dissolved in approximately equal weight fractions. The rate of U removal from crushed glassy samples increases with decreasing average grain size (surface area). Initial rapid loss of a small component (≈ 2.5%) of the total U from crushed felsite. followed by much slower U loss, reflects variable rates of attack of numerous uranium sites. The fractions of U removed during the experiment ranged from 3.2% (felsite) to 27% (perlite). An empirical method for evaluating the relative rate of U loss from contemporaneous volcanic rocks is presented which incorporates leaching results and rock permeability data.

  3. 75 FR 68377 - Notice of Inventory Completion: Anthropological Studies Center, Archaeological Collections...

    Science.gov (United States)

    2010-11-05

    ... associated funerary objects are 8 obsidian tools, 183 obsidian flakes, 30 chert flakes, 4 basalt flakes, 1... individuals were identified. The 54 associated funerary objects are 20 obsidian tools, 1 chert tool, 3...

  4. Obisdian sourcing by PIXE analysis at AURA2

    International Nuclear Information System (INIS)

    Neve, S.R.; Barker, P.H.; Holroyd, S.; Sheppard, P.J.

    1994-01-01

    The technique of Proton Induced X-ray Emission is a suitable method for the elemental analysis of obsidian samples and artefacts. By comparing the elemental composition of obsidian artefacts with those of known sources of obsidian and identifying similarities, the likely origin of the sample can be discovered and information about resource procurement gained. A PIXE facility has now been established at the Auckland University Research Accelerator Laboratory, AURA2. It offers a rapid, multi-element, non-destructive method of characterisation of obsidian samples ranging from small chips to large pieces. In an extensive survey of Mayor Island obsidian, a discrimination has been made between the different locations of obsidian deposits on the island. In addition, using the database developed at AURA2, artefacts from the site of Opita, Hauraki Plains, have been sourced. (Author). 18 refs., 8 figs., 7 tabs., 1 appendix

  5. Complete genome sequence of Geobacillus thermoglucosidasius C56-YS93, a novel biomass degrader isolated from obsidian hot spring in Yellowstone National Park.

    Science.gov (United States)

    Brumm, Phillip J; Land, Miriam L; Mead, David A

    2015-01-01

    Geobacillus thermoglucosidasius C56-YS93 was one of several thermophilic organisms isolated from Obsidian Hot Spring, Yellowstone National Park, Montana, USA under permit from the National Park Service. Comparison of 16 S rRNA sequences confirmed the classification of the strain as a G. thermoglucosidasius species. The genome was sequenced, assembled, and annotated by the DOE Joint Genome Institute and deposited at the NCBI in December 2011 (CP002835). The genome of G. thermoglucosidasius C56-YS93 consists of one circular chromosome of 3,893,306 bp and two circular plasmids of 80,849 and 19,638 bp and an average G + C content of 43.93 %. G. thermoglucosidasius C56-YS93 possesses a xylan degradation cluster not found in the other G. thermoglucosidasius sequenced strains. This cluster appears to be related to the xylan degradation cluster found in G. stearothermophilus. G. thermoglucosidasius C56-YS93 possesses two plasmids not found in the other two strains. One plasmid contains a novel gene cluster coding for proteins involved in proline degradation and metabolism, the other contains a collection of mostly hypothetical proteins.

  6. PRIMER REGISTRO PREHISPÁNICO DE OBSIDIANAS EN EL PIEDEMONTE MERIDIONAL DE LA PROVINCIA DE TUCUMÁN (ARGENTINA: ANÁLISIS TECNOLÓGICO Y DE PROCEDENCIA / First pre Hispanic record of obsidian in the southern foothill of the Tucuman province (Argentina: tech

    Directory of Open Access Journals (Sweden)

    Gabriel Eduardo Miguez

    2015-06-01

    Full Text Available En este trabajo se presentan los resultados del estudio realizado sobre restos de obsidiana, los cuales constituyen los primeros registrados en contextos arqueológicos de las selvas meridionales de la provincia de Tucumán. Estos materiales fueron recuperados en capas estratigráficas del primer milenio D.C. correspondientes al sitio Santa Rosa, el cual se ubica en la base de las laderas orientales de la Sierra del Aconquija (Tucumán, Argentina. Se realizó un análisis técnico-morfológico de los especímenes, en conjunto con un análisis geoquímico mediante fluorescencia de rayos X (FRX para determinar la procedencia geográfica de los materiales de obsidiana. Los resultados determinaron que la materia prima de la muestra, compuesta exclusivamente por desechos de talla, procede de la cantera de Ona-Las Cuevas, la cual se ubica a ca.270 km al noroeste del sitio Santa Rosa, en el norte de la provincia de Catamarca, en la Puna meridional argentina. La gran distancia sitio-cantera nos lleva a proponer que las comunidades prehispánicas de estas tierras bajas habrían participado de esferas estables de interacción con grupos de áreas muy distantes, propiciando la circulación e intercambio de obsidianas dentro de la porción meridional del NO de Argentina. Abstract In this paper we present the results of the study conducted on obsidian specimens, which constitutes the first record of this kind in archaeological contexts of the southern forests of the province of Tucumán are presented. These materials were recovered in stratigraphic layers of the first millennium AD of the Santa Rosa site, which is located at the base of the eastern slopes of the Sierra del Aconquija (Tucumán, Argentina. A techno-morphological analysis of specimens in conjunction with geochemic alanalysis using X-ray fluorescence (XRF was performed to determine the geographical provenance of obsidian archaeological materials. Results determined that the sample raw material

  7. The Unknown Oldowan: ~1.7-Million-Year-Old Standardized Obsidian Small Tools from Garba IV, Melka Kunture, Ethiopia.

    Directory of Open Access Journals (Sweden)

    Rosalia Gallotti

    Full Text Available The Oldowan Industrial Complex has long been thought to have been static, with limited internal variability, embracing techno-complexes essentially focused on small-to-medium flake production. The flakes were rarely modified by retouch to produce small tools, which do not show any standardized pattern. Usually, the manufacture of small standardized tools has been interpreted as a more complex behavior emerging with the Acheulean technology. Here we report on the ~1.7 Ma Oldowan assemblages from Garba IVE-F at Melka Kunture in the Ethiopian highland. This industry is structured by technical criteria shared by the other East African Oldowan assemblages. However, there is also evidence of a specific technical process never recorded before, i.e. the systematic production of standardized small pointed tools strictly linked to the obsidian exploitation. Standardization and raw material selection in the manufacture of small tools disappear at Melka Kunture during the Lower Pleistocene Acheulean. This proves that 1 the emergence of a certain degree of standardization in tool-kits does not reflect in itself a major step in cultural evolution; and that 2 the Oldowan knappers, when driven by functional needs and supported by a highly suitable raw material, were occasionally able to develop specific technical solutions. The small tool production at ~1.7 Ma, at a time when the Acheulean was already emerging elsewhere in East Africa, adds to the growing amount of evidence of Oldowan techno-economic variability and flexibility, further challenging the view that early stone knapping was static over hundreds of thousands of years.

  8. The Unknown Oldowan: ~1.7-Million-Year-Old Standardized Obsidian Small Tools from Garba IV, Melka Kunture, Ethiopia.

    Science.gov (United States)

    Gallotti, Rosalia; Mussi, Margherita

    2015-01-01

    The Oldowan Industrial Complex has long been thought to have been static, with limited internal variability, embracing techno-complexes essentially focused on small-to-medium flake production. The flakes were rarely modified by retouch to produce small tools, which do not show any standardized pattern. Usually, the manufacture of small standardized tools has been interpreted as a more complex behavior emerging with the Acheulean technology. Here we report on the ~1.7 Ma Oldowan assemblages from Garba IVE-F at Melka Kunture in the Ethiopian highland. This industry is structured by technical criteria shared by the other East African Oldowan assemblages. However, there is also evidence of a specific technical process never recorded before, i.e. the systematic production of standardized small pointed tools strictly linked to the obsidian exploitation. Standardization and raw material selection in the manufacture of small tools disappear at Melka Kunture during the Lower Pleistocene Acheulean. This proves that 1) the emergence of a certain degree of standardization in tool-kits does not reflect in itself a major step in cultural evolution; and that 2) the Oldowan knappers, when driven by functional needs and supported by a highly suitable raw material, were occasionally able to develop specific technical solutions. The small tool production at ~1.7 Ma, at a time when the Acheulean was already emerging elsewhere in East Africa, adds to the growing amount of evidence of Oldowan techno-economic variability and flexibility, further challenging the view that early stone knapping was static over hundreds of thousands of years.

  9. Evaluation of new geological reference materials for uranium-series measurements: Chinese Geological Standard Glasses (CGSG) and macusanite obsidian.

    Science.gov (United States)

    Denton, J S; Murrell, M T; Goldstein, S J; Nunn, A J; Amato, R S; Hinrichs, K A

    2013-10-15

    Recent advances in high-resolution, rapid, in situ microanalytical techniques present numerous opportunities for the analytical community, provided accurately characterized reference materials are available. Here, we present multicollector thermal ionization mass spectrometry (MC-TIMS) and multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) uranium and thorium concentration and isotopic data obtained by isotope dilution for a suite of newly available Chinese Geological Standard Glasses (CGSG) designed for microanalysis. These glasses exhibit a range of compositions including basalt, syenite, andesite, and a soil. Uranium concentrations for these glasses range from ∼2 to 14 μg g(-1), Th/U weight ratios range from ∼4 to 6, (234)U/(238)U activity ratios range from 0.93 to 1.02, and (230)Th/(238)U activity ratios range from 0.98 to 1.12. Uranium and thorium concentration and isotopic data are also presented for a rhyolitic obsidian from Macusani, SE Peru (macusanite). This glass can also be used as a rhyolitic reference material, has a very low Th/U weight ratio (around 0.077), and is approximately in (238)U-(234)U-(230)Th secular equilibrium. The U-Th concentration data agree with but are significantly more precise than those previously measured. U-Th concentration and isotopic data agree within estimated errors for the two measurement techniques, providing validation of the two methods. The large (238)U-(234)U-(230)Th disequilibria for some of the glasses, along with the wide range in their chemical compositions and Th/U ratios should provide useful reference points for the U-series analytical community.

  10. 77 FR 25738 - Notice of Intent To Repatriate Cultural Items: Yale Peabody Museum of Natural History, New Haven, CT

    Science.gov (United States)

    2012-05-01

    ... include two stone axes, a stone pestle or hammerstone, two stone pipes, and an obsidian knife. Catalog... Grant County, OR. These objects include sixty-seven obsidian spear heads, arrowheads or similar objects... contexts and some of the obsidian objects appear to have been melted in a fire, possibly a cremation. Based...

  11. Fission-track dating of South American natural glasses: an overview

    Energy Technology Data Exchange (ETDEWEB)

    Bigazzi, G. [Istituto di Geoscienze e Georisorse, C.N.R., Via G. Moruzzi, 1, 56124 Pisa (Italy)]. E-mail: g.bigazzi@igg.cnr.it; Hadler Neto, J.C. [Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP, 13083-970 Campinas SP (Brazil); Iunes, P.J. [Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP, 13083-970 Campinas SP (Brazil); Osorio Araya, A.M. [Departamento de Fisica, Quimica e Biologia, Universidade do Estado de Sao Paulo, UNESP, 19060-900 Presidente Prudente SP (Brazil)

    2005-12-01

    Although many glass-bearing horizons can be found in South American volcanic complexes or sedimentary series, only a relatively few tephra and obsidian-bearing volcanic fields have been studied using the fission-track (FT) dating method. Among them, the volcanics located in the Sierra de Guamani (east of Quito, Ecuador) were studied by several authors. Based upon their ages, obsidians group into three clusters: (1) very young obsidians, {approx}0.2Ma old (2) intermediate-age obsidians, {approx}0.4-{approx}0.8Ma old, and (3) older obsidians, {approx}1.4-{approx}1.6Ma old. The FT method is also an efficient alternative technique for identification of the sources of prehistoric obsidian artefacts. Provenance studies carried out in South America have shown that the Sierra de Guamani obsidian occurrences were important sources of raw material for tool making during pre-Columbian times. Glasses originated from these sources were identified in sites distributed over relatively wide areas of Ecuador and Colombia. Only a few systematic studies on obsidians in other sectors were carried out. Nevertheless, very singular glasses have been recognised in South America, such as Macusanite (Peru) and obsidian Quiron (Argentina), which are being proposed as additional reference materials for FT dating. Analyses of tephra beds interstratified with sedimentary deposits revealed the performance of FT dating in tephrochronological studies. A remarkable example is the famous deposit outcropping at Farola Monte Hermoso, near Bahia Blanca (Buenos Aires Province), described for the first time by the middle of the 19th century by Charles Darwin. Considering the large number of volcanic glasses that were recognised in volcanic complexes and in sedimentary series, South America is a very promising region for the application of FT dating. The examples given above show that this technique may yield important results in different disciplinary fields.

  12. Fission-track dating of South American natural glasses: an overview

    International Nuclear Information System (INIS)

    Bigazzi, G.; Hadler Neto, J.C.; Iunes, P.J.; Osorio Araya, A.M.

    2005-01-01

    Although many glass-bearing horizons can be found in South American volcanic complexes or sedimentary series, only a relatively few tephra and obsidian-bearing volcanic fields have been studied using the fission-track (FT) dating method. Among them, the volcanics located in the Sierra de Guamani (east of Quito, Ecuador) were studied by several authors. Based upon their ages, obsidians group into three clusters: (1) very young obsidians, ∼0.2Ma old (2) intermediate-age obsidians, ∼0.4-∼0.8Ma old, and (3) older obsidians, ∼1.4-∼1.6Ma old. The FT method is also an efficient alternative technique for identification of the sources of prehistoric obsidian artefacts. Provenance studies carried out in South America have shown that the Sierra de Guamani obsidian occurrences were important sources of raw material for tool making during pre-Columbian times. Glasses originated from these sources were identified in sites distributed over relatively wide areas of Ecuador and Colombia. Only a few systematic studies on obsidians in other sectors were carried out. Nevertheless, very singular glasses have been recognised in South America, such as Macusanite (Peru) and obsidian Quiron (Argentina), which are being proposed as additional reference materials for FT dating. Analyses of tephra beds interstratified with sedimentary deposits revealed the performance of FT dating in tephrochronological studies. A remarkable example is the famous deposit outcropping at Farola Monte Hermoso, near Bahia Blanca (Buenos Aires Province), described for the first time by the middle of the 19th century by Charles Darwin. Considering the large number of volcanic glasses that were recognised in volcanic complexes and in sedimentary series, South America is a very promising region for the application of FT dating. The examples given above show that this technique may yield important results in different disciplinary fields

  13. Middle Palaeolithic toolstone procurement behaviors at Lusakert Cave 1, Hrazdan valley, Armenia.

    Science.gov (United States)

    Frahm, Ellery; Feinberg, Joshua M; Schmidt-Magee, Beverly A; Wilkinson, Keith N; Gasparyan, Boris; Yeritsyan, Benik; Adler, Daniel S

    2016-02-01

    Strategies employed by Middle Palaeolithic hominins to acquire lithic raw materials often play key roles in assessing their movements through the landscape, relationships with neighboring groups, and cognitive abilities. It has been argued that a dependence on local resources is a widespread characteristic of the Middle Palaeolithic, but how such behaviors were manifested on the landscape remains unclear. Does an abundance of local toolstone reflect frequent encounters with different outcrops while foraging, or was a particular outcrop favored and preferentially quarried? This study examines such behaviors at a finer geospatial scale than is usually possible, allowing us to investigate hominin movements through the landscape surrounding Lusakert Cave 1 in Armenia. Using our newly developed approach to obsidian magnetic characterization, we test a series of hypotheses regarding the locations where hominins procured toolstone from a volcanic complex adjacent to the site. Our goal is to establish whether the cave's occupants procured local obsidian from preferred outcrops or quarries, secondary deposits of obsidian nodules along a river, or a variety of exposures as encountered while moving through the river valley or across the wider volcanic landscape during the course of foraging activities. As we demonstrate here, it is not the case that one particular outcrop or deposit attracted the cave occupants during the studied time intervals. Nor did they acquire obsidian at random across the landscape. Instead, our analyses support the hypothesis that these hominins collected obsidian from outcrops and exposures throughout the adjacent river valley, reflecting the spatial scale of their day-to-day foraging activities. The coincidence of such behaviors within the resource-rich river valley suggests efficient exploitation of a diverse biome during a time interval immediately preceding the Middle to Upper Palaeolithic "transition," the nature and timing of which has yet to

  14. 75 FR 52013 - Notice of Intent to Repatriate Cultural Items: Field Museum of Natural History, Chicago, IL

    Science.gov (United States)

    2010-08-24

    ... points, 1 stone point or knife, and 1 obsidian point or knife. In 1901, Dr. Merton Miller removed the 12... knife, and obsidian point or knife were each removed from Native American graves located along the... measures 8.8 cm x 3.4 cm. The obsidian point or knife (Field Museum catalog number 69279) has slightly...

  15. Facies volcánicas del depósito de avalancha de detritos del volcán Tata Sabaya, Andes Centrales Volcanic facies of the debris avalanche deposit of Tata Sabaya Volcano, Central Andes

    Directory of Open Access Journals (Sweden)

    Benigno Godoy

    2012-09-01

    Full Text Available Las avalanchas de detritos, asociadas a colapsos parciales de edificios volcánicos, son fenómenos comunes en la evolución de un volcán. Este tipo de flujos son por inestabilidades, que pueden deberse a factores tales como la existencia de zonas afectadas por alteración hidrotermal, cambios climáticos, terremotos, intrusión de magmas en zonas superficiales (criptodomos y/o diques y/o movimiento de fallas bajo el edificio volcánico o cercanas a él. El producto final de estos flujos -denominado depósito de avalancha de detritos (DAD- presenta morfologías típicas de cerrillos y drenajes cerrados. En los Andes Centrales se han reconocido, al menos, 14 centros volcánicos con depósitos de avalancha asociados, entre los que está el volcán Tata Sabaya (Bolivia. El colapso que ha dado origen a este depósito podría haberse generado por una combinación de actividad sísmica y magmática en el volcán. El depósito asociado al colapso parcial de este volcán se distribuye sobre la parte baja del flanco sur del volcán y sobre la parte noroccidental de la cuenca del salar de Coipasa. Cubre una superficie de más de 230 km² y tiene un volumen estimado de 6±1 km³. Sobre la base de las composiciones litológicas, se ha establecido que el depósito está constituido por 6 tipos distintos de cerrillos, los cuales son: lávicos, piroclásticos, sedimentarios mixtos, brecha piroclástica y andesítico-basálticos. Considerando el tipo predominante de cerrillos y su distribución espacial dentro del depósito, se ha definido 6 facies diferentes (Facies de Bloques Toreva, Facies de Cerrillos Volcánicos, Facies Central, Facies de Cerrillos Sedimentarios, Facies Mixta y Facies de Cerrillos de Brecha Piroclástica. Tomando en cuenta la distribución espacial de estas facies, se propone la estructura del paleovolcán previa a su colapso parcial.Debris avalanches associated with partial sector collapse of volcanic edifices are common phenomena in the

  16. Rapid Analysis of Energetic and Geo-Materials Using Laser Induced Breakdown Spectroscopy

    Science.gov (United States)

    2013-04-01

    of geomaterials, including garnet samples collected worldwide88, obsidian samples from the southwestern United States89, and a survey of carbonates...the models based on geographical origin classification. The obsidian samples were collected from multiple sites at the Coso Volcanic Field (CVF) in...performance were found for this application. In a study of the subset of obsidians collected from CVF, models were constructed based on eight different

  17. Multi-method, multi-scale geophysical observations in the Obsidian Pool Thermal Area, Yellowstone National Park

    Science.gov (United States)

    Holbrook, W. S.; Carr, B.; Pasquet, S.; Sims, K. W. W.; Dickey, K.

    2016-12-01

    Despite the prominence of Yellowstone as the world's most active hydrothermal province, relatively little is known about the plumbing systems that link deeper hydrothermal fluids to the charismatic hot springs, geysers and mud pots at the surface. We present the results of a multi-method, multi-scale geophysical investigation of the Obsidian Pool Thermal Area (OPTA) in Yellowstone National Park. OPTA hosts acid-sulfate hot springs and mud pots with relatively low pH. We present the results of seismic refraction, electrical resistivity, time-domain EM (TEM), soil conductivity meter (EMI), and GPR data acquired in July 2016. There is a strong contrast in physical properties in the upper 50 m of the subsurface between the low-lying hydrothermal area and surrounding hills: the hydrothermal area has much lower seismic velocities ( 1 km/s vs 3 km/s) and electrical resistivity ( 20 ohm-m vs 300 ohm-m). A prominent zone of very low resistivity (<10 ohm-m) exists at about 20 m depth beneath all hydrothermal features. Poisson's ratio, calculated from P-wave refraction tomography and surface wave inversions, shows low values beneath the "frying pan," where gas is emerging in small fumaroles, suggesting that Poisson's ratio is an effective "gas detector" in hydrothermal areas. Near-surface resistivity mapped from EMI shows a strong correlation with hydrothermal areas previously mapped by heat flow, with areas of high heat flow generally having low resistivity near the surface. Two exceptions are (1) the "frying pan," which shows a central area of high resistivity (corresponding to escaping gas) surrounding by a halo of low resistivity, and (2) a broad area of low resistivity connecting the hydrothermal centers to the lake, which may be clay deposits. TEM data penetrate up to 200 m in depth and suggest that a reservoir of hydrothermal fluids may underlie the entire area, including beneath the forested hills, at depths greater than 100 m, but that they rise toward the surface in

  18. Complete Genome Sequence of Paenibacillus strain Y4.12MC10, a Novel Paenibacillus lautus strain Isolated from Obsidian Hot Spring in Yellowstone National Park.

    Science.gov (United States)

    Mead, David A; Lucas, Susan; Copeland, Alex; Lapidus, Alla; Cheng, Jan-Feng; Bruce, David C; Goodwin, Lynne A; Pitluck, Sam; Chertkov, Olga; Zhang, Xiaojing; Detter, John C; Han, Cliff S; Tapia, Roxanne; Land, Miriam; Hauser, Loren J; Chang, Yun-Juan; Kyrpides, Nikos C; Ivanova, Natalia N; Ovchinnikova, Galina; Woyke, Tanja; Brumm, Catherine; Hochstein, Rebecca; Schoenfeld, Thomas; Brumm, Phillip

    2012-07-30

    Paenibacillus sp.Y412MC10 was one of a number of organisms isolated from Obsidian Hot Spring, Yellowstone National Park, Montana, USA under permit from the National Park Service. The isolate was initially classified as a Geobacillus sp. Y412MC10 based on its isolation conditions and similarity to other organisms isolated from hot springs at Yellowstone National Park. Comparison of 16 S rRNA sequences within the Bacillales indicated that Geobacillus sp.Y412MC10 clustered with Paenibacillus species, and the organism was most closely related to Paenibacillus lautus. Lucigen Corp. prepared genomic DNA and the genome was sequenced, assembled, and annotated by the DOE Joint Genome Institute. The genome sequence was deposited at the NCBI in October 2009 (NC_013406). The genome of Paenibacillus sp. Y412MC10 consists of one circular chromosome of 7,121,665 bp with an average G+C content of 51.2%. Comparison to other Paenibacillus species shows the organism lacks nitrogen fixation, antibiotic production and social interaction genes reported in other paenibacilli. The Y412MC10 genome shows a high level of synteny and homology to the draft sequence of Paenibacillus sp. HGF5, an organism from the Human Microbiome Project (HMP) Reference Genomes. This, combined with genomic CAZyme analysis, suggests an intestinal, rather than environmental origin for Y412MC10.

  19. Use of Fly Ash in the Mitigation of Alkali-Silica Reaction in Concrete

    Science.gov (United States)

    2010-11-12

    crystallinity of the silica and its solubility. Common reactive minerals susceptible to ASR include strained quartz, cristobalite, opal, obsidian , chert, and... obsidian .[5] Adequate Moisture Adequate moisture, the third and final necessary component for ASR to occur, is one of the key components in the

  20. Research Laboratory of Electronics Annual Report Number 125.

    Science.gov (United States)

    1983-01-01

    approximation for modeling underwater acoustics. The summers of 1983 and 1984 mark the beginning of a series of geophysical and acoustic experiments in the...conditions, modifications in an adaptive noise cancelling algorithm such as the Widrow- Hoff least mean square algorithm, allows one to still reduce the...Stephanie Brown, Fielding Kanbe, Hiroshi Vaidyanathan, A. Ganesh Buchinger, Fritz Kayoun, Pierre H. Wang, Hong.Ming Cerrillo, Manuel V. Konrad, Cristina Wang

  1. L'eta' dell'ossidiana di Pantelleria

    Directory of Open Access Journals (Sweden)

    Rapisarda, Massimo

    2007-10-01

    Full Text Available Obsidian is a volcanic glass which was highly prized in prehistoric times. Since its chemical composition depends on the local characteristics of the lava flow, several analytical methods have been employed to establish the provenance of the obsidian artefacts found in prehistoric sites, to identify the ways of the "ancient trade". These methods have become so successful that, besides distinguishing among different volcanoes, today it is even possible to discriminate among different flows of the same volcano. In fact the identification limit is not due to the method used, but to the intrinsic variability existing within the source. In the western Mediterranean, the two islands of Pantelleria and Lipari supplied all the material used for the artefacts found in Sicily and Tunisia. At Lipari, the differentiation among its sources has been made also on a time basis, with the Fission Tracks method, which determines the age of the mineral. At Pantelleria, chemical analytical methods have been able to distinguish among different layers of the same location. The first traces of obsidian use in the western Mediterranean are dated about 8,000 years ago, at the time of the eruptions of the Lipari flows, although the mineral was already available at Pantelleria. This date is confirmed in Sicily by a coherent set of findings, except for some oddly dated specimens. However, some clues like: the sizeable initial exploitation of Pantelleria obsidian, its gradual substitution almost everywhere by the Liparian mineral and the distribution of the Sicilian most ancient sites (seeming to indicate a diffusion process from west to east, hint that the exploitation of Pantelleria obsidian could have started earlier than today established. In principle the hypothesis is not absurd, if we remember that the first documented use of obsidian by Anatomically Modern Humans belongs to 125 thousand years ago on the shores of the Red Sea and that 65 thousand years ago, men showed

  2. The Valles natural analogue project

    International Nuclear Information System (INIS)

    Stockman, H.; Krumhansl, J.; Ho, C.; McConnell, V.

    1994-12-01

    The contact between an obsidian flow and a steep-walled tuff canyon was examined as an analogue for a highlevel waste repository. The analogue site is located in the Valles Caldera in New Mexico, where a massive obsidian flow filled a paleocanyon in the Battleship Rock tuff. The obsidian flow provided a heat source, analogous to waste panels or an igneous intrusion in a repository, and caused evaporation and migration of water. The tuff and obsidian samples were analyzed for major and trace elements and mineralogy by INAA, XRF, X-ray diffraction; and scanning electron microscopy and electron microprobe. Samples were also analyzed for D/H and 39 Ar/ 4O isotopic composition. Overall,the effects of the heating event seem to have been slight and limited to the tuff nearest the contact. There is some evidence of devitrification and migration of volatiles in the tuff within 10 meters of the contact, but variations in major and trace element chemistry are small and difficult to distinguish from the natural (pre-heating) variability of the rocks

  3. A natural analogue for high-level waste in tuff: Chemical analysis and modeling of the Valles site

    International Nuclear Information System (INIS)

    Stockman, H.W.; Krumhansl, J.L.; Ho, C.K.; Kovach, L.; McConnell, V.S.

    1995-01-01

    The contact between an obsidian flow and a steep-walled tuff canyon was examined as an analogue for a high-level waste repository. The analogue site is located in the Valles Caldera in New Mexico, where a massive obsidian flow filled a paleocanyon in the Battleship Rock Tuff. The obsidian flow provided a heat source, analogous to waste panels or an igneous intrusion in a repository, and caused evaporation and migration of water. The tuff and obsidian samples were analyzed for major and trace elements and mineralogy by INAA, XRF, x-ray diffraction, and scanning electron microscopy and electron microprobe. Samples were also analyzed for D/H and 39 Ar/ 40 Ar isotopic composition. Overall, the effects of the heating event seem to have been slight and limited to the tuff nearest the contact. There is some evidence of devitrification and migration of volatiles in the tuff within 10 m of the contact, but variations in major and trace element chemistry are small and difficult to distinguish from the natural (pre-heating) variability of the rocks

  4. Evaluación de tierras para reforestación (Horche, Guadalajara mediante un índice de Productividad Agraria

    Directory of Open Access Journals (Sweden)

    Hontoria Fernández, C.

    2002-03-01

    Full Text Available The EU is promoting afforestation in countries, like Spain, with areas vulnerable to land degradation and desertification. This paper aims to set up, by mean of Land Evaluation, the marginal lands in order to know which ones are susceptible to change from farm to forest. The Land Evaluation method used in this paper is an adaptation and update of the Riquier et al. (1970. It has been named «Índice de Productividad Agraria (IPA», by mean of which is possible to evaluate the main kind of extensive land use: herbaceous winter-spring and herbaceous summer crops, tree crops, range, and forest, all of then on dry and irrigated system, and the herbaceous and tree crops under conventional tillage and no tillage. The study area with an extension of 50 km2 is in Horche (southwest Guadalajara, central Spain. The Land survey has let distinguish nine mapping units: Cerrillo, Bachos, Plataformas, Vertientes, Glacis-Terrazas, Pie de ladera, Abanicos aluviales and Vegas (rainfed and irrigated. The IPA shows the Vertientes and Glacis-Terrazas with tree crops, and the Abanicos Aluviales and Cerrillos with herbaceous crops are marginal agricultural lands and are susceptible to change from farm to forest.

    [es] La Unión Europea está promoviendo la reforestación en aquellos países, como España, con áreas vulnerables a la degradación y a la desertificación. El propósito de este artículo es delimitar y definir, mediante un método de Evaluación de Tierras, las áreas marginales con el fin de conocer cuáles son susceptibles al cambio de uso agrícola al forestal. El método de Evaluación de Tierras que se utiliza en este artículo es una adaptación y actualización del de Riquier et al. (1970. Se ha denominado «índice de Productividad Agraria (IPA», y permite la Evaluación para los tipos de uso extensivos: cultivos herbáceos de invierno-primavera, cultivos herbáceos de verano, cultivos leñosos, pastizal y forestal, todos

  5. Accessing the application of in situ cosmogenic 14C to surface exposure dating of amorphous SiO2

    Science.gov (United States)

    Cesta, J. M.; Goehring, B. M.; Ward, D. J.

    2017-12-01

    We assess the feasibility and utility of in situ cosmogenic 14C as a geochronometer for landforms composed of amorphous SiO2 through the comparison of 14C surface exposure ages to independently determined eruption ages on Obsidian Dome, California. Landforms composed of amorphous SiO2 phases are difficult to date by conventional cosmogenic nuclide methods due to several complications that may arise (e.g., inability to remove meteoric contamination). The onset of an increased understanding of production rates and analytical measurement of in situ 14C in SiO2 provides an opportunity to address this limitation. Obsidian Dome is a 600-year-old phreatomagmatic dome of the Mono-Inyo Craters located in Inyo County, California, and consists of vesicular pumice, obsidian, and rhyolite. Exposure ages from eight obsidian and banded pumice and obsidian surface samples range from 3947 ± 678 to 914 ± 134 years, all significantly older than the accepted radiocarbon age of 650-550 years. δ13C values for the samples range between +2.65‰ and +1.34‰ and show a negative correlation with CO2 yield. The `too old' exposure ages coupled with this negative correlation between δ13C and CO2 yield suggests the incorporation of an atmospheric component of 14C. Measurement of 14C concentrations in shielded, subsurface samples will assist in isolating the atmospheric 14C component and aid in correcting the surface exposure ages.

  6. Insights into archaeal evolution and symbiosis from the genomes of a nanoarchaeon and its inferred crenarchaeal host from Obsidian Pool, Yellowstone National Park.

    Science.gov (United States)

    Podar, Mircea; Makarova, Kira S; Graham, David E; Wolf, Yuri I; Koonin, Eugene V; Reysenbach, Anna-Louise

    2013-04-22

    A single cultured marine organism, Nanoarchaeum equitans, represents the Nanoarchaeota branch of symbiotic Archaea, with a highly reduced genome and unusual features such as multiple split genes. The first terrestrial hyperthermophilic member of the Nanoarchaeota was collected from Obsidian Pool, a thermal feature in Yellowstone National Park, separated by single cell isolation, and sequenced together with its putative host, a Sulfolobales archaeon. Both the new Nanoarchaeota (Nst1) and N. equitans lack most biosynthetic capabilities, and phylogenetic analysis of ribosomal RNA and protein sequences indicates that the two form a deep-branching archaeal lineage. However, the Nst1 genome is more than 20% larger, and encodes a complete gluconeogenesis pathway as well as the full complement of archaeal flagellum proteins. With a larger genome, a smaller repertoire of split protein encoding genes and no split non-contiguous tRNAs, Nst1 appears to have experienced less severe genome reduction than N. equitans. These findings imply that, rather than representing ancestral characters, the extremely compact genomes and multiple split genes of Nanoarchaeota are derived characters associated with their symbiotic or parasitic lifestyle. The inferred host of Nst1 is potentially autotrophic, with a streamlined genome and simplified central and energetic metabolism as compared to other Sulfolobales. Comparison of the N. equitans and Nst1 genomes suggests that the marine and terrestrial lineages of Nanoarchaeota share a common ancestor that was already a symbiont of another archaeon. The two distinct Nanoarchaeota-host genomic data sets offer novel insights into the evolution of archaeal symbiosis and parasitism, enabling further studies of the cellular and molecular mechanisms of these relationships. This article was reviewed by Patrick Forterre, Bettina Siebers (nominated by Michael Galperin) and Purification Lopez-Garcia.

  7. El Santo Sepulcro. Imagen y funcionalidad espacial en la capilla de la iglesia de San Justo (Segovia

    Directory of Open Access Journals (Sweden)

    Carrero Santamaría, Eduardo

    1997-06-01

    Full Text Available The parish church of San Justo in Segovia is located outside the city, in the suburb of El Cerrillo. Inside the church there are Romanesque wall paintings, an articulated reclining statue of Christ known as el Cristo de los Gascones, a chapel in the first storey of the tower and, finally, a sculptured tympanum in the door that gives way to the chapel. All of them can be dated to the 12th and 13th-centuries. The analysis of these elements gives us the key to the functionality of the tower chapel, as one of the areas dedicated to the devotion of the Holy Sepulchre in Castile.[fr] Hors des murs de la ville de Segovie, au lieu-dit El Cerrillo, se trouve l'église de San Justo. À l'intérieur, il y a un cycle de peintures murales romanes, une sculpture articulée du Christ gisant connue sous le nom de Cristo de los Gascones, une chapelle au-dessous de la tour et un tympan sculpté sur la porte d'accès à la chapelle. Tous ces éléments sont attribués aux XIIᵉ et XIIIᵉ siècle. Leur étude montre que cette chapelle était sans doute dédiée au culte du Saint-Sépulcre en Castille.

  8. LE OSSIDIANE DI PALMAROLA I MARKER DI PROVENIENZA

    Directory of Open Access Journals (Sweden)

    Andrea Macchia

    2012-04-01

    Full Text Available

    Le tracce di ossidiane e la caratterizzazione delle componenti chimiche presenti nei luoghi oggetto di indagini archeologiche, permettono l'individuazione delle antiche rotte commerciali. In Italia le aree individuate sono Monte Arci in Sardegna, Lipari e Pantelleria in Sicilia e Palmarola nel Lazio.

     

    Obsidian  from  Palmarola:  source  markers

    A  chemical  characterization  of  the  main  components  and  traces  of  obsidian  allows identifi cation  of  commercial  routes  in  antiquity.  Obsidian  sources in Prehistoric Italy were mainly four: Monte Arci in Sardinia, the islands of Lipari and Pantelleria in Sicily and the island of Palmarola in Lazio. A survey methodology on samples of obsidian from several Neolithic sites in Lazio has been developed, comparing three different analytical techniques: SEM-EDS, XRF and LA-ICP-MS, in order to obtain a wider range of data to be compared with literature records and processed by Principal Component Analysis (PCA, to defi ne relationships between samples and to assign each finding its origin.

  9. Report of Surface Collection and Testing at 18 Sites Near Abiquiu Reservoir, Northern New Mexico

    Science.gov (United States)

    1989-10-01

    the nineteenth century are described as canvas tents apparently held down by stones and pegs forming a circular structure; most cooking was done...02.) FOSSIL GRAY: Gray to tan chert. This code was used although the type does not represent the classic " fingerprint " chert. Permian. (Materials...signature of Cerro del Medio obsidian, and four artifacts (Cat. nos. 86-775, -836., -842, and -854) correspond with the fingerprint of Obsidian Ridge

  10. Vertical Structural Variation and Their Development of the Sanukayama Rhyolite Lava in Kozushima Island, Japan

    Science.gov (United States)

    Furukawa, K.; Uno, K.; Kanamaru, T.; Nakai, K.

    2017-12-01

    We revealed structural development of the Pleistocene Sanukayama rhyolite lava of Kozushima Island, Japan. The good exposure, with about 130 m thick, provides valuable opportunity to understand the vertical structural variation. This exposure corresponds to the upper half of the lava. The paleomagnetic results show that the lava emplaced in subaerial condition at least in the exposed part. The vertical lithofacies are divided into the pumiceous (25-40 m thick), obsidian (40-60 m), spherulitic (30-50 m) layers from top to base. The pumiceous layer is characterized by massive foliated pumice. The foliation dips are gradually changed from gentle (10-30°) in lower part to steep (around 90°) in upper part. This shows the balloon-like morphology. The massive pumiceous layer would be generated from late stage diapiric inflation of the lava (Fink and Manley, 1987). The obsidian layer is composed of massive and welded-brecciated parts. The ductile-deformed light-colored veins, with a few mm thick, are frequently developed. In the microscopic observation, the veins are composed of broken crystals and obsidian clasts indicating fracturing of the lava followed by ductile deformation such as the RFH process (Tuffen et al., 2003). In this layer, extensive vesiculation and microlite development must have been prevented by higher load pressure and faster cooling, respectively. Consequently, they resulted in formation of the obsidian. The spherulitic layer is characterized by development of the ductile-deformed flow banding. The microscopic observation shows that the bands are formed by the spherulite trail. Furthermore, the microlites are aligned within the spherulites. In the heat-retained inner part of the lava, microlites would be developed around the healed fractures. The microlites acted as nucleation site of spherulite. In transition layer between obsidian and spherulitic layers (obsidian layer. This would be caused by high flow-induced shear arising from their rheological

  11. Episodic Holocene eruption of the Salton Buttes rhyolites, California, from paleomagnetic, U-Th, and Ar/Ar dating

    Science.gov (United States)

    Wright, Heather M.; Vazquez, Jorge A.; Champion, Duane E.; Calvert, Andrew T.; Mangan, Margaret T.; Stelten, Mark E.; Cooper, Kari M.; Herzig, Charles; Schriener Jr., Alexander

    2015-01-01

    In the Salton Trough, CA, five rhyolite domes form the Salton Buttes: Mullet Island, Obsidian Butte, Rock Hill, North and South Red Hill, from oldest to youngest. Results presented here include 40Ar/39Ar anorthoclase ages, 238U-230Th zircon crystallization ages, and comparison of remanent paleomagnetic directions with the secular variation curve, which indicate that all domes are Holocene. 238U-230Th zircon crystallization ages are more precise than but within uncertainty of 40Ar/39Ar anorthoclase ages, suggesting that zircon crystallization proceeded until shortly before eruption in all cases except one. Remanent paleomagnetic directions require three eruption periods: (1) Mullet Island, (2) Obsidian Butte, and (3) Rock Hill, North Red Hill, and South Red Hill. Borehole cuttings logs document up to two shallow tephra layers. North and South Red Hills likely erupted within 100 years of each other, with a combined 238U-230Th zircon isochron age of: 2.83 ± 0.60 ka (2 sigma); paleomagnetic evidence suggests this age predates eruption by hundreds of years (1800 cal BP). Rock Hill erupted closely in time to these eruptions. The Obsidian Butte 238U-230Th isochron age (2.86 ± 0.96 ka) is nearly identical to the combined Red Hill age, but its Virtual Geomagnetic Pole position suggests a slightly older age. The age of aphyric Mullet Island dome is the least well constrained: zircon crystals are resorbed and the paleomagnetic direction is most distinct; possible Mullet Island ages include ca. 2300, 5900, 6900, and 7700 cal BP. Our results constrain the duration of Salton Buttes volcanism to between ca. 5900 and 500 years.

  12. Rhyolitic glasses as natural analogues of nuclear waste glasses: behaviour of an Icelandic glass upon natural aqueous corrosion

    International Nuclear Information System (INIS)

    Magonthier, M.-C.; Petit, J.-C.; Dran, J.-C.

    1992-01-01

    A detailed study of the altered rims present in narrow fissures of a 52 ka-old Icelandic obsidian reveals the behaviour of transition and heavy elements, as well as the mechanism and kinetics of alteration, during glass/solution interaction. These complex altered rims are alkali depleted and consist of alternating layers of Fe-rich aluminosilicate and aluminium thihydroxide. The elemental partitioning observed on this naturally corroded obsidian is supported by laboratory experiments performed on the same glass, the elemental accumulation being explained by the formation of a hydrosilicate. A good correlation exists between the thickness of the altered rims and that calculated from the amounts of Fe and Ti accumulated locally. Thus, immobile elements can be used reliably as indices of the extent of alteration because only near-equilibrium conditions occur. The good agreement between the experimental hydration rate of obsidians and the progress of natural corrosion, leads to the assumption that ion diffusion is the long-term controlling mechanism of corrosion. Such an assumption is supported by the particular distribution of the immobile elements which is due to ion diffusion and coprecipitation processes (self-organization genesis). These observations have implications for nuclear waste disposal topics and support the validity of obsidians as analogues of nuclear waste glasses with respect to some local environmental constraints induced by waste packaging and disposal. (author)

  13. El Parque Portal Bicentenario en Santiago de Chile / Portal Bicentennial Park in Santiago de Chile

    OpenAIRE

    Beach Lobos, Myriam;; Montealegre Klenner, Alberto

    2007-01-01

    Se presenta los principios que orientaron el diseño del Parque Portal Bicentenario, un parque de 50 hás. que será el eje principal de la nueva urbanización “Ciudad Parque Bicentenario”, actualmente en construcción en los terrenos del ex aeropuerto de Los Cerrillos en Santiago de Chile.The following text was submitted to the Architecture Competition together with the project drawings. It presents the principles that leaded the design. The 123 acres park will be the main axis of a new urban dev...

  14. Investigation of a Modern Incipient Stromatolite from Obsidian Pool Prime, Yellowstone National Park: Implications for Early Lithification in the Formation of Light-Dark Stromatolite Laminae

    Science.gov (United States)

    Corsetti, F. A.; Berelson, W.; Pepe-Ranney, C. P.; Mata, S. A.; Spear, J. R.

    2016-12-01

    Stromatolites have been defined multiple ways, but the presence of lamination is common to all definitions. Despite this commonality, the origin of the lamination in many ancient stromatolites remains vague. Lamination styles vary, but sub-mm light-dark couplets are common in many ancient stromatolites. Here, we investigate an actively forming incipient stromatolite from Obsidian Pool Prime (OPP), a hot spring in Yellowstone National Park, to better understand the formation of light-dark couplets similar to many ancient stromatolites in texture and structure. In the OPP stromatolites, a dense network of layer-parallel bundles of cyanobacterial filaments (a dark layer) is followed by an open network of layer-perpendicular or random filaments (a light layer) that reflect a diurnal cycle in the leading edge of the microbial mat that coats the stromatolite's surface. Silica crust encases the cyanobacterial filaments maintaining the integrity of the lamination. Bubbles formed via oxygenic photosynthesis are commonly trapped within the light layers, indicating that lithification occurs rapidly before the bubbles can collapse. The filamentous, non-heterocystous stromatoite-building cyanobacterium from OPP is most closely related to a stromatolite-building cyanobacterium from a hot spring in Japan. Once built, "tenants" from multiple microbial phyla move into the structure, mixing and mingling to produce a complicated integrated biogeochemical signal that may be difficult to untangle in ancient examples. While the cyanobacterial response to the diurnal cycle has been previously implicated in the formation of light-dark couplets, the OPP example highlights the importance of early lithification in maintaining the fabric. Thus, the presence of light-dark couplets and bubble structures may indicate very early lithification and therefore a certain degree of mineral saturation in the ancient ocean or other aquatic system, and that bubble structures, if present, may be evidence

  15. [Bronchial reactivity and mucosal bioamines as criteria for acute bronchitis becoming chronic].

    Science.gov (United States)

    Artem'eva, E G; Latfullin, I A

    2002-01-01

    To study bronchial reactivity and sensitivity with consideration of histamine, serotonin and catecholamines concentration in bronchial mucosa in patients with acute bronchitis (AB) as possible criteria of its becoming chronic. Before the treatment 116 patients with verified AB were examined using inhalation provocative tests (IPT) with histamine, serotonin and obsidian in increasing doses. Also, external respiration function was studied. IPT were repeated after the course of treatment. 87 of 116 AB patients exhibited high bronchial sensitivity and reactivity to inhalations of histamine, serotonin, obsidian. In parallel, there was a rise in the levels of histamine and serotonin and a fall in the level of catecholamines in bronchial mucosa (alveolar macrophages, lymphocytes, neutrophils, mast and APUD-cells). Changes in monoamines concentration in bronchial mucosa were relevant to activity of bronchial inflammation and the presence of obstructive syndrome. Persistent bronchial hyperreactivity to inhalations of histamine and obsidian along with high histamine levels and low level of catecholamines in alveolar macrophages, lymphocytes and mucus is a criterion of bronchitis transformation to chronic one.

  16. Applicability of transfer tensor method for open quantum system dynamics.

    Science.gov (United States)

    Gelzinis, Andrius; Rybakovas, Edvardas; Valkunas, Leonas

    2017-12-21

    Accurate simulations of open quantum system dynamics is a long standing issue in the field of chemical physics. Exact methods exist, but are costly, while perturbative methods are limited in their applicability. Recently a new black-box type method, called transfer tensor method (TTM), was proposed [J. Cerrillo and J. Cao, Phys. Rev. Lett. 112, 110401 (2014)]. It allows one to accurately simulate long time dynamics with a numerical cost of solving a time-convolution master equation, provided many initial system evolution trajectories are obtained from some exact method beforehand. The possible time-savings thus strongly depend on the ratio of total versus initial evolution lengths. In this work, we investigate the parameter regimes where an application of TTM would be most beneficial in terms of computational time. We identify several promising parameter regimes. Although some of them correspond to cases when perturbative theories could be expected to perform well, we find that the accuracy of such approaches depends on system parameters in a more complex way than it is commonly thought. We propose that the TTM should be applied whenever system evolution is expected to be long and accuracy of perturbative methods cannot be ensured or in cases when the system under consideration does not correspond to any single perturbative regime.

  17. Structural Analysis of Silicic Lavas Reveals the Importance of Endogenous Flow During Emplacement

    Science.gov (United States)

    Andrews, G. D.; Martens, A.; Isom, S.; Maxwell, A.; Brown, S. R.

    2017-12-01

    Recent observations of silicic lava flows in Chile strongly suggest sustained, endogeneous flow beneath an insulating carapace, where the flow advances through breakouts at the flow margin. New mapping of vertical exposures around the margin of Obsidian Dome, California, has identified discreet lobe structures in cross-section, suggesting that flow-front breakouts occured there during emplacement. The flow lobes are identified through structural measurements of flow-banding orientation and the stretching directions of vesicles. Newly acquired lidar of the Inyo Domes, including Obsidian Dome, is being analyzed to better understand the patterns of folding on the upper surface of the lavas, and to test for fold vergence patterns that may distinguish between endogenous and exogenous flow.

  18. Climas urbanos y contaminación atmosférica en Santiago de Chile

    Directory of Open Access Journals (Sweden)

    Hugo Romero

    2010-12-01

    Full Text Available Se analizan las relaciones existentes entre temperaturas urbanas y concentraciones de material particulado a una escala que representa la totalidad de la ciudad, destacando su división en dos zonas bien delimitadas, que ubicadas al oriente y poniente de la misma, durante los días de ocurrencia de las peores condiciones de contaminación atmosférica. A escala más detallada, que representa a tipos característicos de morfología urbana, se correlacionan los usos y coberturas de suelos con los niveles de vegetación y las temperaturas de las llamadas "subzonas climáticas", en las comunas de Peñalolén, Santiago Centro y Cerrillos, que representan diversas localizaciones en los espacios naturales y socioeconómicos de la ciudad, concluyéndose que existen áreas de condiciones adversas para la población y configuraciones que resaltan su heterogeneidad y diversidad.Current relationships between urban temperatures and particulate matter concentrations at a scale that is representative of the whole city have been analyzed, highlighting a clear division in two zones, the eastern and western part of the city during the days that register the worst air pollution. On a more detailed scale, based on characteristic urban morphology types, land uses and extensions are correlated with vegetation cover and surface temperatures in so-called climatic sub-zones, in the municipalities of Peñalolén, Santiago Centro and Cerrillos, that represent different urban locations, natural cover and socioeconomic variables across the city. The article concludes that there are areas with adverse conditions for the population and configurations that highlight the heterogeneity and diversity of these municipalities.

  19. Relative leach behavior of waste glasses and naturally occurring glasses

    International Nuclear Information System (INIS)

    Adams, P.B.

    1979-01-01

    Simulated nuclear waste glasses of the sodium-borosilicate type with a low waste loading and of the zinc-borosilicate type with a high waste loading have been compared with obsidians. The resuls indicate that the waste glasses would corrode in normal natural environments at a rate of about 0.1 μm per year at 30 0 C and about 5 μm per year at 90 0 C, compared with obsidians which seem to corrode at, or less than, about 0.01 μm per year at 30 0 C and less than 1 μm per year at 90 0 C. Activation energies for reactions of the two waste glasses with pure water are about 20 kcal/g-mol. 3 figures, 7 tables

  20. Teotihuacan, tepeapulco, and obsidian exploitation.

    Science.gov (United States)

    Charlton, T H

    1978-06-16

    Current cultural ecological models of the development of civilization in central Mexico emphasize the role of subsistence production techniques and organization. The recent use of established and productive archeological surface survey techniques along natural corridors of communication between favorable niches for cultural development within the Central Mexican symbiotic region resulted in the location of sites that indicate an early development of a decentralized resource exploitation, manufacturing, and exchange network. The association of the development of this system with Teotihuacán indicates the importance such nonsubsistence production and exchange had in the evolution of this first central Mexican civilization. The later expansion of Teotihuacán into more distant areas of Mesoamerica was based on this resource exploitation model. Later civilizations centered at Tula and Tenochtitlán also used such a model in their expansion.

  1. Impact fracture experiments simulating interstellar grain-grain collisions

    International Nuclear Information System (INIS)

    Freund, F.; Chang, S.; Dickinson, J.T.

    1990-01-01

    Researchers report on fracture experiments in ultrahigh vacuum (UHV, approximately less than 10 to the -8th power mbar) designed to measure (by means of a quadrupole mass spectrometer, QMS, with microns to ms time resolution) the emission of gases and vapors during and after impact (up to 1.5 sec). Two terrestrial materials were chosen which represent structural and compositional extremes: olivine (San Carlos, AZ), a densely packed Mg-Fe(2+) silicate from the upper mantle, available as 6 to 12 mm single crystals, and obsidian (Oregon), a structurally open, alkaline-SiO2-rich volcanic glass. In the olivine crystals OH- groups have been identified spectroscopically, as well as H2 molecules. Obsidian is a water-rich glass containing OH- besides H2O molecules. Olivine from the mantle often contains CO2, either as CO2-rich fluid in fluid inclusions or structurally dissolved or both. By analogy to synthetic glasses CO2 in the obsidian may be present in form of CO2 molecules in voids of molecular dimensions, or as carbonate anions, CO3(2-). No organic molecules have been detected spectroscopically in either material. Results indicate that refractory oxide/silicates which contain dissolved traces of the H2O and CO/CO2 components but no spectroscopically detectable traces of organics may release complex H-C-O (possibly H-C-N-O) molecules

  2. Fission track dating of volcanic glass: experimental evidence for the validity of the Size-Correction Method

    International Nuclear Information System (INIS)

    Bernardes, C.; Hadler Neto, J.C.; Lattes, C.M.G.; Araya, A.M.O.; Bigazzi, G.; Cesar, M.F.

    1986-01-01

    Two techniques may be employed for correcting thermally lowered fission track ages on glass material: the so called 'size-correcting method' and 'Plateau method'. Several results from fission track dating on obsidian were analysed in order to compare the model rising size-correction method with experimental evidences. The results from this work can be summarized as follows: 1) The assumption that mean size of spontaneous and induced etched tracks are equal on samples unaffected by partial fading is supported by experimental results. If reactor effects such as an enhancing of the etching rate in the irradiated fraction due to the radiation damage and/or to the fact that induced fission releases a quantity of energy slightly greater than spontaneous one exist, their influence on size-correction method is very small. 2) The above two correction techniques produce concordant results. 3) Several samples from the same obsidian, affected by 'instantaneous' as well as 'continuous' natural fading to different degrees were analysed: the curve showing decreasing of spontaneous track mean-size vs. fraction of spontaneous tracks lost by fading is in close agreement with the correction curve constructed for the same obsidian by imparting artificial thermal treatements on induced tracks. By the above points one can conclude that the assumptions on which size-correction method is based are well supported, at least in first approximation. (Author) [pt

  3. The function of prehistoric lithic tools: a combined study of use-wear analysis and FTIR microspectroscopy.

    Science.gov (United States)

    Nunziante Cesaro, Stella; Lemorini, Cristina

    2012-02-01

    The application of combined use-wear analysis and FTIR micro spectroscopy for the investigation of the flint and obsidian tools from the archaeological sites of Masseria Candelaro (Foggia, Italy) and Sant'Anna di Oria (Brindisi, Italy) aiming to clarify their functional use is described. The tools excavated in the former site showed in a very high percentage spectroscopically detectable residues on their working edges. The identification of micro deposits is based on comparison with a great number of replicas studied in the same experimental conditions. FTIR data confirmed in almost all cases the use-wear analysis suggestions and added details about the material processed and about the working procedures. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Poutník ze Země východní. Úvod do problematiky obsidiánové štípané industrie v Čechách

    Czech Academy of Sciences Publication Activity Database

    Burgert, Pavel

    2014-01-01

    Roč. 16, prosinec (2014), s. 25-28 ISSN 1213-1628 R&D Projects: GA MK(CZ) DF12P01OVV032 Keywords : Neolithic * obsidian * raw materials Subject RIV: AC - Archeology, Anthropology, Ethnology OBOR OECD: Archaeology

  5. Štípaná industrie z obsidiánu v Čechách

    Czech Academy of Sciences Publication Activity Database

    Burgert, Pavel

    2015-01-01

    Roč. 67, č. 2 (2015), s. 239-266 ISSN 0323-1267 R&D Projects: GA ČR GA15-16963S Institutional support: RVO:67985912 Keywords : chipped industry * obsidian * Neolithic Subject RIV: AC - Archeology, Anthropology, Ethnology

  6. Původ obsidiánové suroviny v pravěku Čech

    Czech Academy of Sciences Publication Activity Database

    Burgert, Pavel; Přichystal, A.; Prokeš, L.; Petřík, J.; Hušková, S.

    2016-01-01

    Roč. 68, č. 2 (2016), s. 224-234 ISSN 0323-1267 R&D Projects: GA ČR GA15-16963S Institutional support: RVO:67985912 Keywords : chipped industry * obsidian * Bohemia * Neolithic * Upper Palaeolithic * geochemistry * provenance Subject RIV: AC - Archeology, Anthropology, Ethnology

  7. First use of in situ vitrification on radioactive wastes

    International Nuclear Information System (INIS)

    Bowlds, L.

    1992-01-01

    A high-temperature method for containing hazardous wastes, which was first developed in the 1980s, is being adapted for the in situ treatment of buried radioactive wastes by the US DOE's Idaho National Engineering Laboratory (INEL), following its recent report on successful preliminary tests. The method, called in situ vitrification (ISV), is an electrically induced thermal process that melts and fuses soil and wastes into a glass-like material at least as strong as natural obsidian or granite. Gases released during the process are captured and treated by an off-gas treatment system. After the wastes are vitrified, they could be left in place, or the mass could be broken up and transported to a disposal site. The glass-like substance would be chemically and physically similar to obsidian and from 4 to 10 times more durable than typical borosilicate glasses used to immobolize high-level nuclear wastes

  8. Life's Little Joke

    Indian Academy of Sciences (India)

    Stephen Jay Gould wrote extensively and ... I). gun is formidable enough against an obsidian blade, but ... Several times during this history, different branches migrated to Europe, where ... the eminent paleontologist Othniel C Marsh. ... captures pictorially the most common of all misconceptions about the shape and pattern.

  9. Complete and draft genome sequences of six members of the aquificales

    Science.gov (United States)

    Reysenbach, A.-L.; Hamamura, N.; Podar, M.; Griffiths, E.; Ferreira, S.; Hochstein, R.; Heidelberg, J.; Johnson, J.; Mead, D.; Pohorille, A.; Sarmiento, M.; Sehweighofer, K.; Seshadri, R.; Voytek, M.A.

    2009-01-01

    The Aquificales are widespread in marine and terrestrial hydrothermal environments. Here, we report the complete and draft genome sequences of six new members of the Aquificales: two marine species, Persephonella marina strain EX-H1 and Hydrogenivirga strain 128-5-R1 (from the East Pacific Rise, 9??50.3???N, 104??17.5???W, and the Eastern Lau Spreading Center, 176??11.5???W, 20??45.8???S, respectively), and four terrestrial isolates, Sulfuri-hydrogenibium azorense strain Az-Ful, Sulfurihydrogenibium yellowstonense strain SS-5, and Sulfurihydro-genibium strain Y03AOP1 (from Furnas, Azores, Portugal, and Calcite Springs and Obsidian Pool in Yellowstone National Park, United States, respectively), and the only thermoacidophilic isolate, Hydrogenobaculum strain Y04AAS1 (from a stream adjacent to Obsidian Pool). Significant differences among the different species exist that include nitrogen metabolism, hydrogen utilization, Chemotaxis, and signal transduction, providing insights into their ecological niche adaptations. Copyright ?? 2009, American Society for Microbiology. All Rights Reserved.

  10. Complete and draft genome sequences of six members of the Aquificales.

    Science.gov (United States)

    Reysenbach, Anna-Louise; Hamamura, N; Podar, M; Griffiths, E; Ferreira, S; Hochstein, R; Heidelberg, J; Johnson, J; Mead, D; Pohorille, A; Sarmiento, M; Schweighofer, K; Seshadri, R; Voytek, M A

    2009-03-01

    The Aquificales are widespread in marine and terrestrial hydrothermal environments. Here, we report the complete and draft genome sequences of six new members of the Aquificales: two marine species, Persephonella marina strain EX-H1 and Hydrogenivirga strain 128-5-R1 (from the East Pacific Rise, 9 degrees 50.3'N, 104 degrees 17.5'W, and the Eastern Lau Spreading Center, 176 degrees 11.5'W, 20 degrees 45.8'S, respectively), and four terrestrial isolates, Sulfurihydrogenibium azorense strain Az-Fu1, Sulfurihydrogenibium yellowstonense strain SS-5, and Sulfurihydrogenibium strain Y03AOP1 (from Furnas, Azores, Portugal, and Calcite Springs and Obsidian Pool in Yellowstone National Park, United States, respectively), and the only thermoacidophilic isolate, Hydrogenobaculum strain Y04AAS1 (from a stream adjacent to Obsidian Pool). Significant differences among the different species exist that include nitrogen metabolism, hydrogen utilization, chemotaxis, and signal transduction, providing insights into their ecological niche adaptations.

  11. Experimental searches for magnetic monopoles

    International Nuclear Information System (INIS)

    Ross, R.R.

    1976-01-01

    Analysis of the sensitivity of previous negative searches for magnetic monopoles shows that they constitute prior evidence against the monopole interpretation of the event reported as ''evidence for detection of a moving magnetic monopole''. The strength of the evidence varies with the unknown mass of the monopole. For M less than or equal to 10 5 GeV, odds are greater than 10 6 : 1 against. For larger masses, the limits depend strongly on assumptions about the range of monopoles and the threshold for detection of monopole tracks in obsidian. In no case are the odds, less than 8 : 1 and they may be no less than 8000 : 1 against. Since the reported event may also be due to an electrically charged heavy particle, it is probably not due to a monopole

  12. Characterizing the hypersiliceous rocks of Belgium used in (pre-)history: a case study on sourcing sedimentary quartzites

    International Nuclear Information System (INIS)

    Veldeman, Isis; Baele, Jean-Marc; De Doncker, H W J A; Goemaere, Eric; Deceukelaire, Marleen; Dusar, Michiel

    2012-01-01

    Tracking raw material back to its extraction source is a crucial step for archaeologists when trying to deduce migration patterns and trade contacts in (pre-)history. Regarding stone artefacts, the main rock types encountered in the archaeological record of Belgium are hypersiliceous rocks. This is a newly introduced category of rock types comprising those rocks made of at least 90% silica. These are strongly silicified quartz sands or sedimentary quartzites, siliceous rocks of chemical and biochemical origin (e.g. flint), very pure metamorphic quartzites and siliceous volcanic rocks (e.g. obsidian). To be able to distinguish between different extraction sources, ongoing research was started to locate possible extraction sources of hypersiliceous rocks and to characterize rocks collected from these sources. Characterization of these hypersiliceous rocks is executed with the aid of optical polarizing microscopy, optical cold cathodoluminescence and scanning-electron microscopy combined with energy-dispersive x-ray spectrometry and with back-scatter electron imaging. In this paper, we focus on various sedimentary quartzites of Paleogene stratigraphical level. (paper)

  13. An ancient Maya ritual cache at Pook's Hill, Belize

    DEFF Research Database (Denmark)

    Stemp, W. James; Braswell, Geoffrey E.; Helmke, Christophe

    2018-01-01

    , the edge and surface wear on most of the used obsidian blades are consistent with other functions, including cutting meat/skin/fresh hide, cutting or sawing wood and dry hide, cutting or sawing other soft and hard materials, and scraping hard materials. Clearly, not all blades from this ritual deposit were...

  14. 78 FR 13890 - Notice of Intent To Repatriate Cultural Items: San Francisco State University NAGPRA Program, San...

    Science.gov (United States)

    2013-03-01

    ... ethnographic research, the sacred object and object of cultural patrimony is 1 clay pipe fragment. Based on consultation and ethnographic research, the objects of cultural patrimony are 4 obsidian tools or flakes, 5... ethnographic research, the pestle is an object of cultural patrimony. The age of site CA-SON-UNK (Dry Creek) is...

  15. Pseudotectites from Colombia and Peru

    NARCIS (Netherlands)

    Martin, R.; Sitter-Koomans, de C.

    1955-01-01

    In a previous note on “Americanites” (Martin, 1934) from Colombia and Peru, the writer came to the conclusion, on the basis solely of published data, that it was very likely that these so-called tectites are in reality obsidian of terrestrial origin. He stated, however, that “before it is possible

  16. Observation of intensity of cosmic rays and daily magnetic shifts near meridian 70° in the South America

    Science.gov (United States)

    Cordaro, E. G.; Gálvez, D.; Laroze, D.

    2016-05-01

    In analysis of experiments carried during September 2008 using secondary cosmic ray detectors located in Chacaltaya (Bolivia) and Niteroi (Brazil), Augusto et al. (2010) showed an increase in the intensity of charged particles which takes place 3 h after sunrise and lasts until 1 h after sunset, furthermore they said that during this period the solar magnetic field lines overtake the Earth‧s surface. These stations are located within the South Atlantic Magnetic Anomaly (SAMA), having both different magnetic rigidities. To reproduce data from the Niteroi and Chacaltaya stations, we record data during the same hours and days using our neutron monitors, muon telescopes and magnetometers within the stations Putre and Los Cerrillos. Our observation stations in Putre and Cerrillos are located at 18°11‧47.8″S, 69°33‧10.9″W at an altitude of 3600 m and 33°29‧42.3″S, 70°42‧59.81″W with 570 m height above sea level, respectively. These stations are located within the South Atlantic Anomaly (SAMA) and are separated approximately 1700 km from each other and 1700 km from the center of the anomaly. Our network is composed furthermore by two auxiliary Cosmic Ray and/or Geomagnetic stations located at different latitudes along 70°W meridian, LARC and O'Higgins stations, which are located within Antarctic territory, covering a broad part of the Southern Hemisphere. Our magnetometer data shows that for each of the components, shifts in the magnetic field intensity for every station (even for those out of the SAMA) lasted between 3 and 4 h after sunrise and 1 and 2 h past sunset, which are the periods when the geomagnetic field is modulated by the transit of the dayside to nightside and nightside to dayside. We believe that, although the magnetometric data indicates the magnetic reconnection for the Chilean region, there is no direct influence from the SAMA other than the lower rigidity cut-off that leads to an increased count rate. Other details about the

  17. Chapter 5. Plant gathering, game hunting, fishing, mineral collecting, and agriculture

    Science.gov (United States)

    Kurt F. Anschuetz

    2007-01-01

    Native American populations have cut wood for shelters and fuel, gathered native plants, hunted game animals, and collected various other resources, such as obsidian for making chipped-stone tools, clay for crafting pottery vessels, and stone slabs for producing piki (corn meal paper bread) griddles, in the Valles Caldera National Preserve (VCNP) for countless...

  18. Nuclear Physics Group progress report January - December 1982

    International Nuclear Information System (INIS)

    Coote, G.E.

    1983-08-01

    The work of the Nuclear Physics Group of the Institute of Nuclear Sciences during the period July-December 1981 is described. Installation of the EN-tandem electrostatic accelerator proceeded to the voltage test stage. Highlights of the research programme included nuclear microprobe studies of bone and teeth, and depth profiling of sodium in hydrated obsidian

  19. Vitrification development and experiences at Fernald, Ohio

    International Nuclear Information System (INIS)

    Gimpel, R.F.; Paine, D.; Roberts, J.L.; Akgunduz, N.

    1998-01-01

    Vitrification of radioactive wastes products have proven to produce an extremely stable waste form. Vitrification involves the melting of wastes with a mixture of glass-forming additives at high temperatures; when cooled, the wastes are incorporated into a glass that is analogous to obsidian. Obsidian is a volcanic glass-like rock, commonly found in nature. A one-metric ton/day Vitrification Pilot Plant (VITPP) at Fernald, Ohio, simulated the vitrification of radium and radon bearing silo residues using representative non-radioactive surrogates. These non-radioactive surrogates contained high concentrations of lead, sulfates, and phosphates. The vitrification process was carried out at temperatures of 1150 to 1350 C. Laboratory and bench-scale treatability studies were conducted before initiation of the VITPP. Development of the glass formulas, containing up to 90% waste, will be discussed in the paper. The VITPP processed glass for seven months, until a breach of the melter containment vessel suspended operations. More than 70,000 pounds of good surrogate glass were produced by the VITPP. Experiences, lessons learned, and the planned path forward will be presented

  20. Complete Genome Sequence of the Hyperthermophilic Sulfate-Reducing Bacterium Thermodesulfobacterium geofontis OPF15T.

    Science.gov (United States)

    Elkins, James G; Hamilton-Brehm, Scott D; Lucas, Susan; Han, James; Lapidus, Alla; Cheng, Jan-Fang; Goodwin, Lynne A; Pitluck, Sam; Peters, Lin; Mikhailova, Natalia; Davenport, Karen W; Detter, John C; Han, Cliff S; Tapia, Roxanne; Land, Miriam L; Hauser, Loren; Kyrpides, Nikos C; Ivanova, Natalia N; Pagani, Ioanna; Bruce, David; Woyke, Tanja; Cottingham, Robert W

    2013-04-11

    Thermodesulfobacterium geofontis OPF15(T) (ATCC BAA-2454, JCM 18567) was isolated from Obsidian Pool, Yellowstone National Park, and grows optimally at 83°C. The 1.6-Mb genome sequence was finished at the Joint Genome Institute and has been deposited for future genomic studies pertaining to microbial processes and nutrient cycles in high-temperature environments.

  1. On the use of thin natural uranium film dosimetry in mineral dating by the fission track method

    International Nuclear Information System (INIS)

    Hadler Neto, J.C.; Iunes, P.J.; Khouri, M.C.

    1993-01-01

    Three obsidian samples were irradiated in a neutron facility and their age was measured by the fission track method; using a thin uranium film dosemeter. The results were compared to others made previously on the same type of rock using conventional neutron dosimetry. The use of thin uranium film for age determination is discussed. (F.E.). 20 refs, 4 tabs

  2. On the use of the South-American neutron monitors

    Energy Technology Data Exchange (ETDEWEB)

    Cordaro, E. G. [Santiago de Chile Univ., Santiago de Chile (Chile). Facultad de Ciencias Fisicas y Matematicas, Dept. de Fisica, Lewis Research Center; Storini, M. [Consiglio Nazionale delle Ricerche, Istituto di Fisica dello Spazio Interplanetario, Rome (Italy); Rome Univ. Tre, Rome (Italy). Dipt. di Fisica, Raggi Cosmici

    2001-10-01

    Cosmic ray scientific community deserves special attention to the Chacaltaya site for its over 5 km altitude. In this site, a neutron monitor of the IGY type operated from 1960 to 1969, and the one of the NM-64 type since 1966 (16.31{sup 0}S, 291.85{sup 0}E, height: about 5200 m a.s.l.). It was discussed the relevance of such kind of detector when it is integrated with the other South-American neutron monitors: a) LARC (62.20{sup 0}S, 301.04{sup 0}E, height: 40 m a.s.l., King George Island, Antarctica; operating since 1991); b) Los Cerrillos (33.45{sup 0}S, 289.40{sup 0}E, height: 570 m a. s. l., Santiago, Chile; to be installed in the near future); c) Huancayo (12.03{sup 0}S, 284.67{sup 0}E, height: 3400 m a.s.l., Huancayo, Peru; hoping to recover its acquired data).

  3. The Aegean in the Early 7th Millennium BC: Maritime Networks and Colonization.

    Science.gov (United States)

    Horejs, B; Milić, B; Ostmann, F; Thanheiser, U; Weninger, B; Galik, A

    link this background of newcomers to the western edge of Anatolia with new excavation results from Çukuriçi Höyük, which we have analysed in terms of subsistence strategies, materiality, technology and symbolism. Additionally, further detailed studies of nutrition and obsidian procurement shed light on the distinct maritime affinity of the early settlers in our case study, something that, in our view, can hardly be attributed to inland farming societies. We propose a maritime colonization in the 7th millennium via routes from the eastern Mediterranean to the eastern Aegean, based on previously developed sea networks. The pronounced maritime affinity of these farming and herding societies allows us to identify traces of earlier PPN concepts still embedded in the social-cultural memories of the newcomers and incorporated in a new local and regional Neolithic identity.

  4. Submarine silicic volcanism: Processes and products

    Digital Repository Service at National Institute of Oceanography (India)

    Kalangutkar, N.G.; Iyer, S.D.

    hawaiite, mugearite, benmorite and trachyte to rhyolite (Prestvik et al., 2001). A plinian eruption produced rhyolitic ash and pumice while an initial phreatomagmatic explosion gave rise to lithic fragments characterised by bomb-like pumice blocks... blocks and bombs Selbekk and Tronnes (2007) Granophyres, rhyolites obsidian O’nions and Gronvold (1973) Rhyolite Sigvaldason (1974) Ascension and the Azores Quartz saturated residue Clague (1987) 14 Azores and the Canaries Silica oversaturated...

  5. Кремневые и обсидиановые микролиты из нижних культурных слоев стоянки позднего палеолита Косэуць

    Directory of Open Access Journals (Sweden)

    Covalenco Sergei

    2017-09-01

    Full Text Available The article is devoted to the description of microlithic finds from the lower cultural layers of the Late Paleolithic Cosautsy site (Moldova. Particular attention is drawn to the finds from the fifth layer - flint and obsidian artifacts of the "rectangle" type, flint micro-points with a blunted edge, including needle-shaped and lancet. All of them correspond to the epigravete techno- complex widely spread in Middle Transnistria.

  6. From The Mountain To The Sea: Exchange Between The South-Central Highlands And The South Coast During The Early Horizon Period

    OpenAIRE

    Young, Michele

    2017-01-01

    This article reviews the evidence of the exchange of obsidian and cinnabar, highly coveted resources that traveled in prehistoric Peru from the south-central highlands to the Paracas culture area. The evidence for exchange of these materials is compared with evidence of cultural exchange between the coast and the south-central highlands, focusing on ceramic materials uncovered from excavations at the archaeological site Atalla, located in the region of Huancavelica, Peru. The article argues t...

  7. Characterization of Particles Created By Laser-Driven Hydrothermal Processing

    Science.gov (United States)

    2016-06-01

    study for two reasons: (i) Both materials are compositionally high in SiO2 and (ii) form similarly to glass formed by a nuclear explosion, which...creates massive pressures and temperatures. As an example, trinitite is a glass formed by a post-nuclear event with SiO2 making up 50%-75% of its...processing, characterization, obsidian, tektite, natural glass 15. NUMBER OF PAGES 89 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT

  8. Real-time monitoring and control of the plasma hearth process

    International Nuclear Information System (INIS)

    Power, M.A.; Carney, K.P.; Peters, G.G.

    1996-01-01

    A distributed monitoring and control system is proposed for a plasma hearth, which will be used to decompose hazardous organic materials, encapsulate actinide waste in an obsidian-like slag, and reduce storage volume of actinide waste. The plasma hearth will be installed at ANL-West with the assistance of SAIC. Real-time monitoring of the off-gas system is accomplished using a Sun Workstation and embedded PCs. LabWindows/CVI software serves as the graphical user interface

  9. Stone as material for production of chipped artifacts in Early and Middle Neolithic of Serbia

    Directory of Open Access Journals (Sweden)

    Šarić Josip A.

    2002-01-01

    Full Text Available In this work we studied artifacts from 20 Early and Middle Neolithic sites in Serbia. Stone used as raw material for production of chipped tools are defined and we pointed to inadequate usage of certain terms. By using of the data from geologic literature and statistical analysis of representation of certain stone at distinct sites we present assumption about location of primary occurrence of so called "Balkan flint" and obsidian in the territory of Serbia.

  10. Sun River (24CA74): A Stratified Pelican Lake and Oxbow Occupation Site near Great Falls, Montana.

    Science.gov (United States)

    1983-08-31

    artifacts from 24CA74 are consistently of a dark, homogeneous variety probably derived from the Obsidian Cliffs in Yellowstone National Park (Davis...pollen columns from a pond on the east side of Yellowstone Park, Wyoming, place the Altithermal from 9,000 to 4,500 years ago. At Waterton Lakes National...of a wolf’s upper third molar (carnassial) (Fig. 4-12a). This tooth fragment is of interest because it could be interpreted as evidence of wolves

  11. ARO - Terrestrial Research Program, Methodologies and Protocols for Characterization of Geomaterials

    Science.gov (United States)

    2015-05-14

    approach of chemical fingerprinting has been used to determine the source areas of rock artifacts, ceramics, cultural glass, obsidian artifacts, ancient...dation for the analysis of 38 cassiterite samples classified by country of origin Model classes Test samples (# of Examples) Bolivia Peru Thailand...Indonesia Brazil Malaysia Bolivia (19) 83 % 0 1 % 2 % 3 % 6 % Peru (9) 3 % 94 % 1 % 0 % 0 % 2 % Thailand (4) 0 0 99 % 0 0 1 % Indonesia (4) 0 0 1 % 99 % 0 0

  12. Candidate OP Phyla: Importance, Ecology and Cultivation Prospects.

    Science.gov (United States)

    Rohini Kumar, M; Saravanan, V S

    2010-10-01

    OP phyla were created in the domain bacteria, based on the group of 16S rRNA gene sequences recovered from the Obsidian Pool. However, due to the lack of cultured representative it is referred to as candidate phyla. Wider ecological occurrence was predicted for the OP phyla, especially OP3, OP10 and OP11. Recently, members of phylum OP5 and OP10 were cultured, providing clues to their cultivation prospects. At last the bioprospecting potentials of the OP members are discussed herein.

  13. Hydrothermal alteration of a rhyolitic hyaloclastite from Ponza Island, Italy

    Science.gov (United States)

    Ylagan, Robert F.; Altaner, Stephen P.; Pozzuoli, Antonio

    1996-12-01

    A rhyolitic hyaloclastite from Ponza island, Italy, has been hydrothermally altered producing four distinct alteration zones based on XRD and field textures: (1) non-pervasive argillic zone; (2) propylitic zone; (3) silicic zone; and (4) sericitic zone. The unaltered hyaloclastite is a volcanic breccia with clasts of vesiculated obsidian in a matrix of predominantly pumice lapilli. Incomplete alteration of the hyaloclastite resulted in the non pervasive argillic zone, characterized by smectite and disordered opal-CT. Obsidian clasts, some pumice lapilli, and pyrogenic plagioclase and biotite are unaltered. Smectite has an irregular flakey morphology, although euhedral particles are occasionally observed. The propylitic zone is characterized by mixed-layer illite/smectite (I/S) with 10 to 85% illite (I), mordenite, opal-C and authigenic K-feldspar (akspar). The matrix of the hyaloclastite is completely altered and obsidian clasts are silicified; however, plagioclase and biotite phenocrysts remain unaltered. Flakey I/S replaces pumice, and mordenite, akspar and silica line and fill pores. I/S particles are composed predominantly of subequant plates and euhedral laths. The silicic zone is characterized by highly illitic I/S with ≥ 90% I, quartz, akspar and occasional albite. In this zone the matrix and clasts are completely altered, and pyrogenic plagioclase shows significant alteration. Illitic I/S has a euhedral lath-like morphology. In the sericitic zone the hyaloclastite altered primarily to illitic I/S with ≥ 66% I, quartz, and minor akspar and pyrite. Clay minerals completely replace pyrogenic feldspars and little evidence remains of the original hyaloclastite texture. Unlike other zones, illitic I/S is fibrous and pure illite samples are composed of euhedral laths and hexagonal plates. The temperatures of hydrothermal alteration likely ranged from 30 to 90 °C for the argillic zone, from 110 to 160 °C for the propylitic zone, from 160 to 270 °C for the

  14. Impact fracture experiments simulating interstellar grain-grain collisions

    Science.gov (United States)

    Freund, Friedemann; Chang, Sherwood; Dickinson, J. Thomas

    1990-01-01

    Oxide and silicate grains condensing during the early phases of the formation of the solar system or in the outflow of stars are exposed to high partial pressures of the low-z elements H, C, N and O and their simple gaseous compounds. Though refractory minerals are nominally anhydrous and non-carbonate, if they crystallize in the presence of H2O, N2 and CO or CO2 gases, they dissolve traces of the gaseous components. The question arises: How does the presence of dissolved gases or gas components manifest itself when grain-grain collisions occur. What are the gases emitted when grains are shattered during a collision event. Researchers report on fracture experiments in ultrahigh vacuum (UHV, approximately less than 10 to the -8th power mbar) designed to measure (by means of a quadrupole mass spectrometer, QMS, with microns to ms time resolution) the emission of gases and vapors during and after impact (up to 1.5 sec). Two terrestrial materials were chosen which represent structural and compositional extremes: olivine (San Carlos, AZ), a densely packed Mg-Fe(2+) silicate from the upper mantle, available as 6 to 12 mm single crystals, and obsidian (Oregon), a structurally open, alkaline-SiO2-rich volcanic glass. In the olivine crystals OH- groups have been identified spectroscopically, as well as H2 molecules. Obsidian is a water-rich glass containing OH- besides H2O molecules. Olivine from the mantle often contains CO2, either as CO2-rich fluid in fluid inclusions or structurally dissolved or both. By analogy to synthetic glasses CO2 in the obsidian may be present in form of CO2 molecules in voids of molecular dimensions, or as carbonate anions, CO3(2-). No organic molecules have been detected spectroscopically in either material. Results indicate that refractory oxide/silicates which contain dissolved traces of the H2O and CO/CO2 components but no spectroscopically detectable traces of organics may release complex H-C-O (possibly H-C-N-O) molecules upon fracture

  15. Analysis of Red Pigments from the Neolithic sites of Çatalhöyük in Turkey and Sheikh-e Abad in Iran.

    Science.gov (United States)

    Anderson, Emma; Almond, Matthew J; Matthews, Wendy; Cinque, Gianfelice; Frogley, Mark D

    2014-10-15

    Samples containing red pigment have been collected from two different archaeological sites dating to the Neolithic (Çatalhöyük in Turkey and Sheikh-e Abad in Iran) and have been analysed by a range of techniques. Sub-samples were examined by IR spectroscopy and X-ray diffraction, whilst thin sections were studied using optical polarising microscopy, synchrotron based IR microscopy and environmental scanning electron microscopy with energy dispersive X-ray analysis. Thin layers of red paint in a wall painting from Çatalhöyük were found to contain ochre (hematite and clay) as well as an unexpected component, grains of red and colourless obsidian, which have not been identified in any previous studies of the wall paintings at Çatalhöyük. These small grains of obsidian may have improved the reflective properties of the paint and made the artwork more vivid in the darkness of the buildings. Analysis of a roughly shaped ball of red sediment found on a possible working surface at Sheikh-e Abad revealed that the cause of the red colouring was the mineral hematite, which was probably from a source of terra rossa sediment in the local area. The results of this work suggest it is unlikely that this had been altered by the Neolithic people through mixing with other minerals. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Sustainable Innovation of Glass Design and Craft

    DEFF Research Database (Denmark)

    Sparre-Petersen, Maria

    2014-01-01

    but an ongoing process of re-directing the way we design our world and thereby our future. This approach along with further research into sustainable development within the field of design and combined with material specific methodologies may reveal new possibilities for sustainable as well as aesthetic...... windows to beads. Glass is a natural material and can be found in nature in the form of i.e. obsidian and fulgurites. Glass in itself does not impact the environment negatively, but mining and transportation of raw materials and production of new glass products contributes to CO2 emission. Therefore...

  17. ESCA studies on leached glass forms

    International Nuclear Information System (INIS)

    Dawkins, B.G.

    1979-01-01

    Electron Spectroscopy for Chemical Analysis (ESCA) results for frit, obsidian, NBS standard, and Savannah River Laboratory (SRL) glass forms that have been subjected to cumulative water leachings of 36 hours show that [Na] exhibits the largest and fastest change of all the elements observed. Leaching of surface Na occurred within minutes. Surface Na depletion increased with leach time. Continuous x-ray irradiation and argon ion milling induced Na mobility, precluding semiquantitative ESCA analysis at normal operating temperatures. However, the sample stage has been equipped with a liquid nitrogen supply and alkali mobility should be eliminated in future work

  18. CASE REPORT CASE CASE Post-traumatic cholesteatoma … a ...

    African Journals Online (AJOL)

    CASE REPORT. CASE. 46. SA JOURNAL OF RADIOLOGY • July 2008. CASE. Abstract. Temporal bone fractures and their acute complications have been well described in radiology and ENT journals; this is in contrast to ... post-traumatic cholesteatomas and made postulations on their origin. Since then, there have been ...

  19. Understanding the processes involved in weathering and experimental alteration of glassy materials. The case of some volcanic glasses from eastern Sicily (Italy)

    International Nuclear Information System (INIS)

    Liotta, Angelo

    2014-01-01

    The objective of this thesis is to study the effects of weathering and experimental alteration in order to understand the geochemical processes involved and the variation of mineral phases in altered natural glasses. For the first time, five samples of natural volcanic glasses having different composition were collected in eastern Sicily (Italy) in order to be artificially altered and analyzed. The study of naturally altered samples has allowed to observe the effects of weathering after a period of time corresponding to the age of the sample. Moreover, the use of samples of natural glass of volcanic origin has allowed to obtain some powder or thin plates of fresh silicate glass that have been subjected to artificial alteration in the laboratory, in order to model the geochemical processes that have occurred. Alteration experiments were conducted in pure water at 90 C; samples have been altered from 1 to 1000 days of experiment. The characterization of the samples was obtained by Raman spectroscopy, which showed the effects of the devitrification and the presence of some secondary minerals such as carbonates and anatase on the obsidian thin plates, but also phillipsite and chabazite, two varieties of zeolite usually found in the cavities of oldest basalts. Solid modifications were observed by SEM. The analysis showed the formation of several secondary minerals having a composition compatible with smectites, determined by EDS spectroscopy. All these results allow to test the geochemical modeling in the long term. Further analysis will be needed to reach a full understanding of the weathering of glassy materials. (author)

  20. The Case for Case Reports

    Directory of Open Access Journals (Sweden)

    George R. Saade

    2011-09-01

    Full Text Available If you are reading a hard copy of this editorial, then you are holding in hand the first issue of the American Journal of Perinatology Reports, or AJP Reports as we like to refer to it. Welcome to AJP Reports and thank you for taking the time to peruse it. I hope you find many of the reports interesting and helpful. The editorial team and publisher are very pleased to be able to bring this journal to our readers. Judging by the journal title, the editorial team, and the layout you may have already guessed that this is a companion to the American Journal of Perinatology. We will continue to publish original articles and topical reviews in the American Journal of Perinatology, but all case reports or case series will be referred to AJP Reports. Some may question the need for more case reports. Our decision to start AJP Reports obviously indicates that we think that case reports can be useful. I can refer to several diseases, treatment complications, and procedures that were first brought to the attention of healthcare providers through case reports. The best example of the usefulness of case reports is probably in infectious diseases. In the early phases of an emerging infectious disease, the case report or case series are usually the first clues of a problem. HIV was first brought to the attention of the medical community by case reports.[1] [2] [3] In our own field, the first attempts at treatment of twin-to-twin transfusion syndrome (TTTS using laser coagulation were reported in a case series.[4] After additional reports about the use of laser in TTTS, a randomized trial was performed that cemented laser photocoagulation as a therapeutic modality for TTTS.[5] While case reports or series are not considered the highest form of evidence, they are frequently the first form of evidence and the nudge that starts the cascade of investigation that ultimately leads to high-level evidence. Therefore, their impact on clinical practice may be easily

  1. The Cretan Mesolithic in context: new data from Livari Skiadi (SE Crete

    Directory of Open Access Journals (Sweden)

    Tristan Carter

    2016-12-01

    Full Text Available Investigations at Livari (south-eastern Crete produced a small Mesolithic chipped stone assemblage, whose techno-typological characteristics situate it within an ‘early Holocene Aegean island lithic tradition’ (9000–7000 cal BC. The material provides antecedent characteristics for the lithics of Crete’s founder Neolithic population at Knossos (c. 7000–6500/6400 cal BC. The idiosyncrasies of the Knossian material can be viewed as a hybrid lithic tradition that emerged from interaction between migrant Anatolian farmers and indigenous hunter-gatherers. Small quantities of Melian obsidian at Livari attest to early Holocene maritime insular networks, knowledge of which likely enabled the first farmers’ successful voyage to Crete.

  2. A social perspective on the Neolithic in western Iran

    Directory of Open Access Journals (Sweden)

    Hojjat Darabi

    2016-12-01

    Full Text Available While the Neolithic revolution caused gradual basic changes in different dimensions of human life, including social structure, western Iran has so far mostly received attention in terms of the emergence of domestication and sedentarisation. Generally speaking, some evidence, such as architectural elements, burial goods, clay tokens, and scarce artefacts such as obsidian pieces and marble objects not only determine an inter-regional interaction, but also suggest craft specialisation. It is believed that sedentary life and private food storage paved the way for property ownership and that a gradual change from egalitarian to non-egalitarian societies can be seen in the Neolithic of western Iran.

  3. El patrimonio rupestre de Gran Canaria. Los grabados de la Montaña de Las Vacas (Aldea de San Nicolás

    Directory of Open Access Journals (Sweden)

    Ernesto Martín Rodríguez

    2013-11-01

    Full Text Available Se presentan varias estaciones rupestres inéditas para la investigación, localizadas en el curso de los trabajos arqueológicos llevados a cabo en la Montaña de Hogarzales (Aldea de San Nicolás, Gran Canaria en torno a la explotación de la obsidiana por las comunidades prehistóricas de la isla.One presents rock art unpublished stations for the investigation, located in the course of the archaeological works led to end in Hogarzales's mountain (Village of San Nicolas, Great Canary concerning the exploitation of the obsidian for the prehistoric communities of the island.

  4. Case Study: Testing with Case Studies

    Science.gov (United States)

    Herreid, Clyde Freeman

    2015-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue discusses using case studies to test for knowledge or lessons learned.

  5. Progress report of Physics Division. 1st August 1974 - 30th September 1975. Acting Division Chief - Mr. W. Gemmell

    International Nuclear Information System (INIS)

    2004-01-01

    Customer satisfaction with the introduced uranium analysis service has produced additional requests for service type assistance. Two are currently being studied: a quick method of analysis for thorium and characterization of the source of obsidian archaeological artifacts. Several nuclear techniques have been brought to bear on obsidian with consistent and reproducible results. Source material has been identified of unknown origin. The techniques are now being used to study trading patterns by the movement of obsidian flakes between the Pacific Islands. The neutron capture cross sections for more isotopes have been analyzed. The data in the 3 to 300 keV energy range was obtained at the Oak Ridge Electron Linear Accelerator facility in 1972. In addition to providing accurate neutron capture cross sections and resonance parameters suitable for inclusion in neutron data libraries, the information yielded provided a good test of several of the current theories of nuclear structure - valence model and doorway states. Several reviews of problem areas in nuclear energy were undertaken. Of particular note are those on 'Hydraulic Methods for Blow down of Water Cooled Reactors', 'The Storage and Disposal of Radioactive Waste' and 'The Technological Problems of Fusion Reactors'. An examination of our knowledge of oceanic transport of pollutants has followed on from the examination of the radioactive waste disposal options. In addition to the development of a code - NAIAD - for the analysis of blow down, analytical work on the well documented SPERT experiments has produced a satisfactory quantitative explanation without invoking ad hoc assumptions. The method is now being applied to safety studies of the two local reactors. The proposals for experimental study of water flow on the White's mining tailings mound at Rum Jungle received a setback as a result of cyclone Tracy. Preparations are now complete to install a weir on the White's mound during the dry season. This will

  6. Archaeological investigations on the Buckboard Mesa Road Project

    Energy Technology Data Exchange (ETDEWEB)

    Amick, D.S.; Henton, G.H.; Pippin, L.C.

    1991-10-01

    In 1986, the Desert Research Institute (DRI) conducted an archaeological reconnaissance of a new alignment for the Buckboard Mesa Road on the Nevada Test Site for the Department of Energy (DOE). During this reconnaissance, several archaeological sites of National Register quality were discovered and recorded including a large quarry, site 26Ny4892, and a smaller lithic scatter, site 26Ny4894. Analysis of the debitage at 26Ny4892 indicates that this area was used primarily as a quarry for relatively small cobbles of obsidian found in the alluvium. Lithic reduction techniques used here are designed for efficiently reducing small pieces of toolstone and are oriented towards producing flake blanks from small cores and bifacially reducing exhausted cores. Projectile point cross references indicate that the area has seen at least casual use for about 10,000 years and more sustained use for the last 3,000 years. Initial obsidian hydration measurements indicate sustained use of the quarry for about the last 3,000 years although the loci of activities appear to change over time. Based on this study, the DRI recommends that quarrying activities in the area of 26Ny4892 are sufficiently sampled and that additional investigations into that aspect of prehistoric activity in the area are not necessary. This does not apply to other aspects of prehistoric use. DRI recommends that preconstruction surveys continue to identify nonquarrying, prehistoric utilization of the area. With the increased traffic on the Buckboard Mesa Road, there is a greater potential for vandalism to sites of National Register-quality located near the road. The DRI recommends that during the orientation briefing the workers at the Test Site be educated about the importance of cultural resources and the need for their protection. 202 refs., 41 figs., 52 tabs.

  7. A scientific approach to Plato's Atlantis

    Directory of Open Access Journals (Sweden)

    Massimo Rapisarda

    2015-09-01

    Full Text Available The myth of Atlantis is hard to die. This attempt to use scientific evidence to give it the final smash ends up with the doubt that it might not be totally unsubstantiated. The time of the supposed existence of Atlantis (around twelve thousand years ago was, in fact, characterized by technological revolutions, acknowledged by archaeology, and abrupt climate changes, documented by geology. In principle, it cannot therefore be ruled out that some of those dramatic events left a memory, later used by Plato as a basis for its tale. The climate changes involved the majority of the northern hemisphere, thus all the ancient civilizations (Egyptian, Mesopotamian, Indian and Chinese could have preserved reminiscence, but it is clear that the events occurring closer to Greece would have been more accessible to Plato. Among the Mediterranean sites that experienced the cataclysms of the beginning of the Holocene, a good candidate to host a primordial civilization might have been the archipelago then existing in the Strait of Sicily, a natural maritime link between Tunisia and Italy, prized by the presence of an obsidian source at Pantelleria. Eleven thousand five hundred years ago, a sudden sea level rise erased the archipelago, submerging the possible settlements, but Pantelleria obsidian ores are still there and could provide a significant clue. In fact, the potential discovery of artefacts, originating from a source now submerged by the sea level rise, would imply that the collection of the mineral took place when it was still emerged, namely at the time of Atlantis. Even if such discovery would not be sufficient to prove the existence of the mythical island, it would be enough to shake up the timeline of the human occupation in the region.

  8. Natural analogues of nuclear waste glass corrosion

    International Nuclear Information System (INIS)

    Abrajano, T.A. Jr.; Ebert, W.L.; Luo, J.S.

    1999-01-01

    This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an engineered geologic disposal system. A wide range of natural and experimental corrosion studies has been performed on three major groups of natural glasses: tektite, obsidian, and basalt. Studies of the corrosion of natural glass attempt to characterize both the nature of alteration products and the reaction kinetics. Information available on natural glass was then compared to corresponding information on the corrosion of nuclear waste glasses, specifically to resolve two key questions: (1) whether one or more natural glasses behave similarly to nuclear waste glasses in laboratory tests, and (2) how these similarities can be used to support projections of the long-term corrosion of nuclear waste glasses. The corrosion behavior of basaltic glasses was most similar to that of nuclear waste glasses, but the corrosion of tektite and obsidian glasses involves certain processes that also occur during the corrosion of nuclear waste glasses. The reactions and processes that control basalt glass dissolution are similar to those that are important in nuclear waste glass dissolution. The key reaction of the overall corrosion mechanism is network hydrolysis, which eventually breaks down the glass network structure that remains after the initial ion-exchange and diffusion processes. This review also highlights some unresolved issues related to the application of an analogue approach to predicting long-term behavior of nuclear waste glass corrosion, such as discrepancies between experimental and field-based estimates of kinetic parameters for basaltic glasses

  9. Natural analogues of nuclear waste glass corrosion.

    Energy Technology Data Exchange (ETDEWEB)

    Abrajano, T.A. Jr.; Ebert, W.L.; Luo, J.S.

    1999-01-06

    This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an engineered geologic disposal system. A wide range of natural and experimental corrosion studies has been performed on three major groups of natural glasses: tektite, obsidian, and basalt. Studies of the corrosion of natural glass attempt to characterize both the nature of alteration products and the reaction kinetics. Information available on natural glass was then compared to corresponding information on the corrosion of nuclear waste glasses, specifically to resolve two key questions: (1) whether one or more natural glasses behave similarly to nuclear waste glasses in laboratory tests, and (2) how these similarities can be used to support projections of the long-term corrosion of nuclear waste glasses. The corrosion behavior of basaltic glasses was most similar to that of nuclear waste glasses, but the corrosion of tektite and obsidian glasses involves certain processes that also occur during the corrosion of nuclear waste glasses. The reactions and processes that control basalt glass dissolution are similar to those that are important in nuclear waste glass dissolution. The key reaction of the overall corrosion mechanism is network hydrolysis, which eventually breaks down the glass network structure that remains after the initial ion-exchange and diffusion processes. This review also highlights some unresolved issues related to the application of an analogue approach to predicting long-term behavior of nuclear waste glass corrosion, such as discrepancies between experimental and field-based estimates of kinetic parameters for basaltic glasses.

  10. Case - Case-Law - Law

    DEFF Research Database (Denmark)

    Sadl, Urska

    2013-01-01

    Reasoning of the Court of Justice of the European Union – Constr uction of arguments in the case-law of the Court – Citation technique – The use of formulas to transform case-law into ‘law’ – ‘Formulaic style’ – European citizenship as a fundamental status – Ruiz Zambrano – Reasoning from...

  11. In Situ Vitrification: Recent test results for a contaminated soil melting process

    International Nuclear Information System (INIS)

    Buelt, J.L.; Timmerman, C.L.; Westsik, J.H. Jr.

    1988-06-01

    In Situ Vitrification (ISV) is being developed at Pacific Northwest Laboratory for the Department of Energy and other clients for the stabilization of soils and sludges contaminated with radioactive and hazardous chemical wastes. ISV is a process that immobilizes contaminated soil in place by converting it to a durable glass and crystalline product that is similar to obsidian. In June 1987, a large-scale test of the process was completed at a transuranic- contaminated soil site. This constituted the first full-scale demonstration of the ISV process at an actual site. This paper summarizes the preliminary results of this test and describes the processes' potential adaptation to radioactive and hazardous chemical waste contaminated soils. 10 refs., 10 figs

  12. In situ vitrification: Test results for a contaminated soil-melting process

    International Nuclear Information System (INIS)

    Buelt, J.L.; Timmerman, C.L.; Westsik, J.H. Jr.

    1989-10-01

    In situ vitrification (ISV) is being developed at Pacific Northwest Laboratory for the Department of Energy to stabilize soils and sludges that are contaminated with radioactive and hazardous chemical wastes. ISV is a process that immobilizes contaminated soil in place by converting it to a durable glass and crystalline product similar to obsidian and basalt. In June 1987, a large-scale test of the process was completed at a transuranic-contaminated soil site. The test constituted the first full-scale demonstration of ISV at an actual site. This paper summarizes the results of that test and describes the potential adaptation of the process to radioactive and hazardous chemical waste-contaminated soils. 15 refs., 9 figs., 3 tabs

  13. Industrial collaborators honoured by ALICE

    CERN Document Server

    Maximilien Brice

    2004-01-01

    Picture 01 : the winners gather after the ALICE Award ceremony (from left to right): Yuri Saveliev, Stanislav Burachas and Sergei Beloglovsky of North Crystals; Maximilian Metzger, CERN's secretary-general; Rang Cai of ATM; Jürgen Schukraft, ALICE spokesperson; Erich Pamminger and Daniel Gattinger of FACC; and Tiejun Wang of ATM. The ALICE collaboration has presented its second round of awards to three companies for their novel and remarkable contributions to major detector systems: Advance Technology and Materials (ATM), Fischer Advanced Composite Components (FACC) and North Crystals. The awards presented to these three leaders in advanced, modern materials were beautifully sculpted from one of the oldest materials used by mankind to manufacture tools - Mexican Obsidian

  14. Casing study

    Energy Technology Data Exchange (ETDEWEB)

    Roche, P.

    2000-12-01

    An unorthodox method of casing drilling used by Tesco Corporation at a gas well in Wyoming to drill deeper using casings as drillpipe is discussed. The process involves either rotating the casing as drill string or using a downhole mud motor to rotate the bit. In this instance, the surface hole and the production hole were casing-drilled to a record 8,312 feet by rotating the casing. The 8 1/2-inch surface hole was drilled with 7-inch casing to 1,200 feet using a Tesco underreamer and a polycrystalline pilot bit; drilling and cementing was completed in 12 1/2 hours. The 6 1/4-inch production hole was drilled with 4 1/2-inch casing and the bottomhole assembly was retrieved after 191 hours rotating. This case was the first in which the entire well was casing-drilled from surface to TD. Penetration rate compared favorably with conventional methods: 12 1/2 hours for casing-drilling to 18.9 hours for conventional drilling, despite the fact that the casing-drilling technology is still in its infancy. It is suggested that casing-drilling has the potential to eliminate the need for the drillpipe entirely. If these expectations were to be realised, casing-drilling could be one of the most radical drilling changes in the history of the oil and gas industry. 1 photo.

  15. Case management.

    Science.gov (United States)

    Woodward, Judy; Rice, Eve

    2015-03-01

    Health care in the United States is changing rapidly under pressure from both political and professional stakeholders, and one area on the front line of required change is the discipline of case management. Historically, case management has worked to defragment the health care delivery system for clients and increase access to health care. Case management will have an expanded role resulting from Affordable Care Act initiatives to improve health care. This article includes definitions of case management, current issues related to case management, case management standards of practice, and a case study of the management of pediatric chronic disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Stories as case knowledge: case knowledge as stories.

    Science.gov (United States)

    Cox, K

    2001-09-01

    Every case contains a human story of illness and a medical story of disease, which together cover person management, case management, health system management and self-management. Much of that management can be learned via a thorough set of stories of typical and atypical core cases compiled by clinical teachers. Stories provide a highly flexible framework for illustrating the lessons of experience, the tips and traps for young players, and the dilemmas requiring careful judgement in the trade-offs between benefits and risks. Listening to real stories unfold is much more fun than being lectured (and better remembered). Stories illustrate 'what can happen' in a case as a guide to 'what to do'. A story begins with a real world situation with some predicament and a (causal) sequence of events or plot in which things are resolved one way or another. Patients tell their illness story; their clinician translates that into a disease story. Stories sort out what is important in such a predicament, consider the strategy and tactics of what to do, and speak about the outcomes. Each local situation provides relevance, context and circumstantial detail. Stories about case management can encapsulate practical knowledge, logical deduction, judgement and decision making, sharing with the student all the ingredients that develop expertise. Sometimes it is the plot that is important, sometimes the detail, sometimes it is the underlying message, the parable that resonates with the listener's experiences and feelings.1 Stories can also accommodate the complexity of multiple variables and the influence of other stakeholders, the uncertainties and dilemmas within the trade-offs, and the niceties of 'informed judgement'. This paper makes four points. First, clinical stories recount pointed examples of 'what happened' that expand our expertise in handling 'a case like that'. Second, cases are the unit of clinical work. Case stories expand the dimensions and details of case knowledge

  17. Location of gliomas in relation to mobile telephone use: a case-case and case-specular analysis

    DEFF Research Database (Denmark)

    Larjavaara, Suvi; Schüz, Joachim; Swerdlow, Anthony

    2011-01-01

    approaches: In a case-case analysis, tumor locations were compared with varying exposure levels; in a case-specular analysis, a hypothetical reference location was assigned for each glioma, and the distances from the actual and specular locations to the handset were compared. The study included 888 gliomas......The energy absorbed from the radio-frequency fields of mobile telephones depends strongly on distance from the source. The authors' objective in this study was to evaluate whether gliomas occur preferentially in the areas of the brain having the highest radio-frequency exposure. The authors used 2...... from 7 European countries (2000-2004), with tumor midpoints defined on a 3-dimensional grid based on radiologic images. The case-case analyses were carried out using unconditional logistic regression, whereas in the case-specular analysis, conditional logistic regression was used. In the case-case...

  18. [Case-non case studies: Principles, methods, bias and interpretation].

    Science.gov (United States)

    Faillie, Jean-Luc

    2017-10-31

    Case-non case studies belongs to the methods assessing drug safety by analyzing the disproportionality of notifications of adverse drug reactions in pharmacovigilance databases. Used for the first time in the 1980s, the last few decades have seen a significant increase in the use of this design. The principle of the case-non case study is to compare drug exposure in cases of a studied adverse reaction with that of cases of other reported adverse reactions and called "non cases". Results are presented in the form of a reporting odds ratio (ROR), the interpretation of which makes it possible to identify drug safety signals. This article describes the principle of the case-non case study, the method of calculating the ROR and its confidence interval, the different modalities of analysis and how to interpret its results with regard to the advantages and limitations of this design. Copyright © 2017 Société française de pharmacologie et de thérapeutique. Published by Elsevier Masson SAS. All rights reserved.

  19. Early Neolithic settlement patterns and exchange networks in the Aegean

    Directory of Open Access Journals (Sweden)

    Agathe Reingruber

    2011-12-01

    Full Text Available The Neolithisation process is one of the major issues under debate in Aegean archaeology, since the description of the basal layers of Thessalian tell-settlements some fifty years ago. The pottery, figurines or stamps seemed to be of Anatolian origin, and were presumably brought to the region by colonists. The direct linking of the so-called ‘Neolithic Package’ with groups of people leaving Central Anatolia after the collapse of the Pre-Pottery Neolithic B resulted in the colonisation model of the Aegean. This view is not supported by results obtained from natural sciences such as archaeobotany, radiocarbon analyses, and neutron activation on obsidian. When theories of social networks are brought into the discussion, the picture that emerges becomes much more differentiated and complex.

  20. Evaluation of ammonium bifluoride fusion for rapid dissolution in post-detonation nuclear forensic analysis

    International Nuclear Information System (INIS)

    Hubley, Nicholas T.; Brockman, John D.; Robertson, J. David; Missouri Univ., Columbia, MO

    2017-01-01

    Dissolution of geological reference materials by fusion with ammonium bifluoride, NH_4HF_2 or ABF, was evaluated for its potential use in post-detonation nuclear forensics. The fusion procedure was optimized such that the total dissolution time was <3 h without compromising recovery. Geological reference materials containing various levels of silicates were dissolved and measured by ICP-MS to quantify elemental recovery. Dissolutions of NIST 278 obsidian and urban canyon matrix were performed with radiotracer spikes to measure potential loss of volatile elements during the fusion procedure via gamma-ray spectroscopy. Elemental percent recoveries obtained by ICP-MS were found to be 80-120% while recoveries of radiotracers were observed to be 90-100% with the exception of iodine.

  1. Evaluation of ammonium bifluoride fusion for rapid dissolution in post-detonation nuclear forensic analysis

    Energy Technology Data Exchange (ETDEWEB)

    Hubley, Nicholas T. [Missouri Univ., Columbia, MO (United States). Dept. of Chemistry; Brockman, John D. [Missouri Univ., Columbia, MO (United States). Research Reactor Center; Robertson, J. David [Missouri Univ., Columbia, MO (United States). Research Reactor Center; Missouri Univ., Columbia, MO (United States). Dept. of Chemistry

    2017-10-01

    Dissolution of geological reference materials by fusion with ammonium bifluoride, NH{sub 4}HF{sub 2} or ABF, was evaluated for its potential use in post-detonation nuclear forensics. The fusion procedure was optimized such that the total dissolution time was <3 h without compromising recovery. Geological reference materials containing various levels of silicates were dissolved and measured by ICP-MS to quantify elemental recovery. Dissolutions of NIST 278 obsidian and urban canyon matrix were performed with radiotracer spikes to measure potential loss of volatile elements during the fusion procedure via gamma-ray spectroscopy. Elemental percent recoveries obtained by ICP-MS were found to be 80-120% while recoveries of radiotracers were observed to be 90-100% with the exception of iodine.

  2. Using existing case-mix methods to fund trauma cases.

    Science.gov (United States)

    Monakova, Julia; Blais, Irene; Botz, Charles; Chechulin, Yuriy; Picciano, Gino; Basinski, Antoni

    2010-01-01

    Policymakers frequently face the need to increase funding in isolated and frequently heterogeneous (clinically and in terms of resource consumption) patient subpopulations. This article presents a methodologic solution for testing the appropriateness of using existing grouping and weighting methodologies for funding subsets of patients in the scenario where a case-mix approach is preferable to a flat-rate based payment system. Using as an example the subpopulation of trauma cases of Ontario lead trauma hospitals, the statistical techniques of linear and nonlinear regression models, regression trees, and spline models were applied to examine the fit of the existing case-mix groups and reference weights for the trauma cases. The analyses demonstrated that for funding Ontario trauma cases, the existing case-mix systems can form the basis for rational and equitable hospital funding, decreasing the need to develop a different grouper for this subset of patients. This study confirmed that Injury Severity Score is a poor predictor of costs for trauma patients. Although our analysis used the Canadian case-mix classification system and cost weights, the demonstrated concept of using existing case-mix systems to develop funding rates for specific subsets of patient populations may be applicable internationally.

  3. CASING DRILLING TECHNOLOGY

    Directory of Open Access Journals (Sweden)

    Nediljka Gaurina-Međimurec

    2005-12-01

    Full Text Available Casing drilling is an alternative option to conventional drilling and uses standard oilfield casing instead of drillstring. This technology is one of the greatest developments in drilling operations. Casing drilling involves drilling and casing a well simultaneously. In casing driling process, downhole tools can be retrieved, through the casing on wire-line, meaning tool recovery or replacement of tools can take minutes versus hours under conventional methods. This process employs wireline-retrievable tools and a drill-lock assembly, permitting bit and BHA changes, coring, electrical logging and even directional or horizontal drilling. Once the casing point is reached, the casing is cemented in place without tripping pipe.

  4. The case for the case report: refine to save.

    LENUS (Irish Health Repository)

    Lennon, P

    2012-01-31

    INTRODUCTION: The case report is the cornerstone of both medical teaching and writing. However, during recent years the value of the case report has been questioned, so much so that it has been abandoned by many journals. The aim of this study was to assess case reports published by the Irish Journal of Medical Science (IJMS) and to examine ways to preserve this type of article. METHODS: A review of all single-patient case reports published in the IJMS in 2008 and 2009. RESULTS: Forty-eight cases were published from nine countries. The range of authors was 2-11, length 525-1,787 words and number of references 4-24. All cases contained abstracts. CONCLUSION: Stricter guidelines with regards to a shorter more focused article should help to preserve this form of publication.

  5. CASE REPORT CASE CASE R The many faces of hydatid disease

    African Journals Online (AJOL)

    CASE R. Case report. A 35-year-old man presented with a right chest wall mass. Chest radio- graphs revealed pleural thickening underlying a soft tissue mass which obscured the 5th to 7th ribs, and an expansile osteolytic lesion of the 7th rib. Ultrasound examination demonstrated a fluid-filled cystic lesion of the chest wall ...

  6. CASE STUDY CRITIQUE; UPPER CLINCH CASE STUDY

    Science.gov (United States)

    Case study critique: Upper Clinch case study (from Research on Methods for Integrating Ecological Economics and Ecological Risk Assessment: A Trade-off Weighted Index Approach to Integrating Economics and Ecological Risk Assessment). This critique answers the questions: 1) does ...

  7. Case series

    African Journals Online (AJOL)

    ebutamanya

    2015-01-29

    Jan 29, 2015 ... for tinnitus (Table 1). The otomicroscopic examination shows: central non marginal perforation in 29 patients, posterior perforation in 17 patients and anterior perforation in 14 patients. The tympanic cavity was dry in 27 cases, wet in 18 cases and inflammatory in the. 15 remaining cases. The conralateral ear ...

  8. Case report

    African Journals Online (AJOL)

    ebutamanya

    2015-02-12

    Feb 12, 2015 ... Abstract. Vaginal metastasis from pancreatic cancer is an extreme case and often indicates a poor prognosis. We present a case of pancreatic carcinoma with metastasis to the vagina that was discovered by vaginal bleeding. To our knowledge, this is the third case in the world of a primary pancreatic.

  9. Useful Business Cases

    DEFF Research Database (Denmark)

    Nielsen, Peter Axel; Persson, John Stouby

    2017-01-01

    during implementation and value creation. This article presents lessons learned from our action research, lessons that we incorporated into a business case method and subsequently evaluated with IS managers. There are three lessons on: (1) improving the content of business cases, (2) how to develop...... research study seeks to improve the usefulness of business cases in IS projects. We used collaborative action research with Danish municipalities to improve their practices when developing and using business cases and to change their perceptions of what constitutes a good business case that is useful...... business cases, and (3) the use of business cases in subsequent value creation. These lessons summarize our findings and the contributions are that we in the business case method propose to: (1) include minimal contents, (2) develop social commitment, and (3) structure for dynamic use during value creation...

  10. Pure Case and Prepositional Case in Russian

    DEFF Research Database (Denmark)

    Durst-Andersen, Per; Lorentzen, Elena

    2017-01-01

    By considering Russian case as the nominal equivalent to mood whereby its semantic functions are emphasized at the expense of its syntactic functions, it is demonstrated that the nominative, accusative, vocative and genitive cases constitute a mini system in which the nominative and the accusative...

  11. Running casing on conventional wells with Casing Drilling {sup TM} technology

    Energy Technology Data Exchange (ETDEWEB)

    Warren, T.M.; Schneider, W.P.; Johns, R.P.; Zipse, K.D. [Tesco Corp., Calgary, AB (Canada)

    2004-07-01

    Casing Drilling{sup TM} is a newly developed and efficient well construction method that combines drilling and casing running processes into a single operation. This radical change to the entire well casing running process eliminates standard components and processes that are inefficient and hazardous. The commercialization of this new technology has resulted in the development of custom equipment and procedures designed to efficiently handle casings on a drilling rig, including conventionally drilled wells. The technology offers safer casing running operations and makes it possible to ream casing to the bottom. In addition, less people are needed to operate the portable Casing Drive System (CDS). One of the primary components of the system is the top drive which provides the power for rotation and torque. The CDS supports full axial and torsional load for running the casing. The well can be circulated while running the casing. The casing can be washed and reamed to the bottom whenever a tight hole is encountered. Thirty one operators have successfully used the CDS on more than 150 onshore and offshore wells in 7 countries. 13 refs., 2 tabs., 12 figs.

  12. Comparison of Emergency Medicine Malpractice Cases Involving Residents to Non-Resident Cases.

    Science.gov (United States)

    Gurley, Kiersten L; Grossman, Shamai A; Janes, Margaret; Yu-Moe, C Winnie; Song, Ellen; Tibbles, Carrie D; Shapiro, Nathan I; Rosen, Carlo L

    2018-04-17

    Data are lacking on how emergency medicine (EM) malpractice cases with resident involvement differs from cases that do not name a resident. To compare malpractice case characteristics in cases where a resident is involved (resident case) to cases that do not involve a resident (non-resident case) and to determine factors that contribute to malpractice cases utilizing EM as a model for malpractice claims across other medical specialties. We used data from the Controlled Risk Insurance Company (CRICO) Strategies' division Comparative Benchmarking System (CBS) to analyze open and closed EM cases asserted from 2009-2013. The CBS database is a national repository that contains professional liability data on > 400 hospitals and > 165,000 physicians, representing over 30% of all malpractice cases in the U.S (> 350,000 claims). We compared cases naming residents (either alone or in combination with an attending) to those that did not involve a resident (non-resident cohort). We reported the case statistics, allegation categories, severity scores, procedural data, final diagnoses and contributing factors. Fisher's exact test or t-test was used for comparisons (alpha set at 0.05). Eight hundred and forty-five EM cases were identified of which 732 (87%) did not name a resident (non-resident cases), while 113 (13%) included a resident (resident cases) (Figure 1). There were higher total incurred losses for non-resident cases (Table 1). The most frequent allegation categories in both cohorts were "Failure or Delay in Diagnosis/Misdiagnosis" and "Medical Treatment" (non-surgical procedures or treatment regimens i.e. central line placement). Allegation categories of Safety and Security, Patient Monitoring, Hospital Policy and Procedure and Breach of Confidentiality were found in the non-resident cases. Resident cases incurred lower payments on average ($51,163 vs. $156,212 per case). Sixty six percent (75) of resident vs 57% (415) of non-resident cases were high severity claims

  13. Heavy metals in sediments associated with anourous assemblies in agroecosystems of North Argentine

    Science.gov (United States)

    Gonzalez Turu, Nancy; Cáceres Díaz, Raúl Omar; Acosta, Rebeca

    2017-04-01

    Heavy metals come from anthropogenic sources, agricultural and industrial, constitute a danger to aquatic biota and are used as an indicator of environmental deterioration. In agroecosystems that use pesticides, surface accumulation occurs by drift and runoff at lower levels of land that are appropriate spaces for the anurans' reproductive activities. Thus, heavy metals usually accumulate in surface sediments and generate an environment of chronic toxicity. The study was carried out at the Experimental Agricultural Station INTA Salta, Cerrillos, pcia. Of Salta, located at 24 ° 53'45''South and 65 ° 27'51''West at a height of 1240 meters. The annual average temperature is 23.8 ° C, the annual variation of the average temperature, corresponds to the "continental" type, with the maximum in the month of December and the minimum in June. The average annual temperature of the soil at 0.10 m. Of depth is 20.4 ° C. The annual distribution of the precipitations indicates the existence of a rainy season between October and April, that concentrates 90% of the precipitations and another one dries the rest of the year, with 720 mm. Of annual rainfall. The soils are of little development of horizons, corresponding to Inceptisols, Ustocrept udico, Series Cerrillos, of alluvial origin, well drained, developed on medium to fine textures, free to loamy loam, poor in organic matter and nitrogen. Soils of fluvio lacustrine origin, rich in silt and weak aggregation. Amphibians have been able to exploit the resources provided by agroecosystems and remain in a metapopulation system within an altered landscape. However, there is a tendency to decrease the density and diversity of amphibians in highly disturbed areas. Some authors suggest that changes in the patterns of amphibian diversity that inhabit agricultural landscapes allow inferring the depopulation of species less tolerant to environmental transformation associated with intensive and sustained agricultural activities over

  14. Synthesis of mordenite in geothermal wells

    Energy Technology Data Exchange (ETDEWEB)

    Konoya, M [Geological Survey of Hokkaido, Japan

    1970-03-01

    A study of the possible synthesis of mordenite in geothermal wells was conducted. In 1966 as part of a series of exploratory geothermal investigations, a 500 m well was drilled which had a temperature at 250 m of 120/sup 0/C. The well has constant temperature and constant pressure and has been used to study alteration. Specimens which were placed in the well were tested for mordenite. Mordenite was synthesized when Benki clay and a 10% KOH solution were placed in a Teflon tube at 250 m (120/sup 0/C and 22.3 kg/cm/sup 2/) for three months. No mordenite was synthesized when obsidian powder was used. These results indicate the possibility of synthesis of zeolite and clay minerals in geothermal wells. Two figures and four tables are provided.

  15. Neutron activation analysis in archaeological chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Harbottle, G [Brookhaven National Lab., Upton, NY (United States)

    1990-01-01

    There is a long history of the application of chemical analysis to archaeological problems, extending to the last years of the 18th century. The nuclear-age technique of neutron activation analysis, permitting the simultaneous, sensitive, non-destructive estimation of many elements in an archaeological specimen, has found wide application. Important advances have been made, using this technique, in locating the origins of archaeological artifacts such as ceramics, metals, obsidian and semiprecious stones, among other articles of ancient ritual and commerce. In addition, the technique of neutron activation analysis has proved to be almost ideal in studies tracing the development of ancient technologies such as glass-making and smelting. In the future, the development of data banks of analyses of archaeological materials should provide an excellent new tool in studies of prehistory.

  16. Neutron activation analysis in archaeological chemistry

    International Nuclear Information System (INIS)

    Harbottle, G.

    1990-01-01

    There is a long history of the application of chemical analysis to archaeological problems, extending to the last years of the 18th century. The nuclear-age technique of neutron activation analysis, permitting the simultaneous, sensitive, non-destructive estimation of many elements in an archaeological specimen, has found wide application. Important advantages have been made, using this technique, in locating the origins of archaeological artifacts such as ceramics, metals, obsidian and semiprecious stones, among other articles of ancient ritual and commerce. In addition, the technique of neutron activation analysis has proved to be almost ideal in studies tracing the development of ancient technologies such as glass-making and smelting. In the future, the development of data banks of analyses of archaeological materials should provide an excellent new tool in studies of prehistory. (orig.)

  17. Cryptococcosis in captive cheetah (Acinonyx jubatus : two cases : case report

    Directory of Open Access Journals (Sweden)

    L.A. Bolton

    1999-07-01

    Full Text Available Cryptococcus neoformans is a yeast-like organism associated with pulmonary, meningoencephalitic, or systemic disease. This case report documents 2 cases of cryptococcosis with central nervous system involvement in captive cheetah (Acinonyx jubatus. In both cases the predominant post mortal lesions were pulmonary cryptococcomas and extensive meningoencephalomyelitis. Both cheetahs tested negative for feline immunodeficiency virus and feline leukaemia virus. The organism isolated in Case 2 was classified as Cryptococcus neoformans var. gattii, which is mainly associated with disease in immunocompetent hosts.

  18. Eruption dynamics and explosive-effusive transitions during the 1400 cal BP eruption of Opala volcano, Kamchatka, Russia

    Science.gov (United States)

    Andrews, Benjamin J.; Dufek, Josef; Ponomareva, Vera

    2018-05-01

    Deposits and pumice from the 1400 cal BP eruption of Opala volcano record activity that occurred at the explosive-effusive transition, resulting in intermittent, or stop-start, behavior, where explosive activity resumed following a pause. The eruption deposited distinctive, biotite-bearing rhyolite tephra across much of Kamchatka, and its stratigraphy consists of a lithic-rich pumice fall, overlain by pumice falls and pyroclastic density deposits, with the proportion of the latter increasing with height. This sequence repeats such that the middle of the total deposit is marked by a lithic-rich fall with abundant obsidian clasts. Notably, the eruptive pumice are poorly vesiculated, with vesicle textures that record fragmentation of a partially collapsed magmatic foam. The eruption vent, Baranii Amphitheater is filled with obsidian lavas of the same composition as the rhyolite tephra. Based upon the stratigraphic and compositional relations, we divide the eruption into four phases. Phase I initiated with eruption of a lithic-rich pumice fall, followed by eruption of Plinian falls and pyroclastic density currents. During Phase II, the eruption paused for at least 5-6 h; in this time, microlites nucleated and began to grow in the magma. Phase III essentially repeated the Phase I sequence. Obsidian lavas were emplaced during Phase IV. The pumice textures suggest that the magma ascended very near the threshold decompression rate for the transition between explosive (fast) and effusive (slow) behavior. The pause during Phase II likely occurred as decompression slowed enough for the magma to develop sufficient permeability for gas to escape resulting in collapse of the magmatic foam, stopping the eruption and temporarily sealing the conduit. After about 5-6 h, eruption resumed with, once again, magma decompressing very near the explosive-effusive transition. Phase III ended when the decompression rate slowed and lava dome emplacement began. Distributions of pumice and

  19. Raw materials exploitation in Prehistory of Georgia: sourcing, processing and distribution

    Science.gov (United States)

    Tushabramishvili, Nikoloz; Oqrostsvaridze, Avthandil

    2016-04-01

    Study of raw materials has a big importance to understand the ecology, cognition, behavior, technology, culture of the Paleolithic human populations. Unfortunately, explorations of the sourcing, processing and distribution of stone raw materials had a less attention until the present days. The reasons of that were: incomplete knowledge of the archaeologists who are doing the late period archaeology (Bronze Age-Medieval) and who are little bit far from the Paleolithic technology and typology; Ignorance of the stone artifacts made on different kind of raw-materials, except flint and obsidians. Studies on the origin of the stone raw materials are becoming increasingly important since in our days. Interesting picture and situation have been detected on the different sites and in different regions of Georgia. In earlier stages of Middle Paleolithic of Djruchula Basin caves the number of basalt, andesite, argillite etc. raw materials are quite big. Since 130 000 a percent of the flint raw-material is increasing dramatically. Flint is an almost lonely dominated raw-material in Western Georgia during thousand years. Since approximately 50 000 ago the first obsidians brought from the South Georgia, appeared in Western Georgia. Similar situation has been detected by us in Eastern Georgia during our excavations of Ziari and Pkhoveli open-air sites. The early Lower Paleolithic layers are extremely rich by limestone artifacts while the flint raw-materials are dominated in the Middle Paleolithic layers. Study of these issues is possible to achieve across chronologies, the origins of the sources of raw-materials, the sites and regions. By merging archaeology with anthropology, geology and geography we are able to acquire outstanding insights about those populations. New approach to the Paleolithic stone materials, newly found Paleolithic quarries gave us an opportunities to try to achieve some results for understanding of the behavior of Paleolithic populations, geology and

  20. Project management case studies

    CERN Document Server

    Kerzner, Harold R

    2013-01-01

    A new edition of the most popular book of project management case studies, expanded to include more than 100 cases plus a ""super case"" on the Iridium Project Case studies are an important part of project management education and training. This Fourth Edition of Harold Kerzner''s Project Management Case Studies features a number of new cases covering value measurement in project management. Also included is the well-received ""super case,"" which covers all aspects of project management and may be used as a capstone for a course. This new edition:Contains 100-plus case studies drawn from re

  1. Case Report Case Report

    African Journals Online (AJOL)

    User

    2013-03-26

    Mar 26, 2013 ... c Medicine and Palliative Cancer Care: A Case Report. Sanjoy Kumar Pal ... us complementary and alternative therapies for treatment about the .... controlled trials that homeopathy may be effective for the treatment of ...

  2. Case Study: Guidelines for Producing Videos to Accompany Flipped Cases

    Science.gov (United States)

    Prud'homme-Généreux, Annie; Schiller, Nancy A.; Wild, John H.; Herreid, Clyde Freeman

    2017-01-01

    Three years ago, the "National Center for Case Study Teaching in Science" (NCCSTS) was inspired to merge the case study and flipped classroom approaches. The resulting project aimed to create the materials required to teach a flipped course in introductory biology by assigning videos as homework and case studies in the classroom. Three…

  3. FHEO Filed Cases

    Data.gov (United States)

    Department of Housing and Urban Development — The dataset is a list of all the Title VIII fair housing cases filed by FHEO from 1/1/2007 - 12/31/2012 including the case number, case name, filing date, state and...

  4. Case series

    African Journals Online (AJOL)

    abp

    2013-06-20

    Jun 20, 2013 ... ... by a persistent neurological deficit in 2 cases, and infection in 2 cases controlled ... Upper cervical spine injuries are frequent due to increasing number .... the patient; it also takes more time for fracture healing and expose.

  5. Comparative Test Case Specification

    DEFF Research Database (Denmark)

    Kalyanova, Olena; Heiselberg, Per

     This document includes a definition of the comparative test cases DSF200_3 and DSF200_4, which previously described in the comparative test case specification for the test cases DSF100_3 and DSF200_3 [Ref.1]....... This document includes a definition of the comparative test cases DSF200_3 and DSF200_4, which previously described in the comparative test case specification for the test cases DSF100_3 and DSF200_3 [Ref.1]....

  6. The impact of staff case manager-case management supervisor relationship on job satisfaction and retention of RN case managers.

    Science.gov (United States)

    Hogan, Tierney D

    2005-01-01

    A positive relationship between staff RN case managers and their case management supervisor significantly impacts job satisfaction and retention in case managers. Literature review supports the premise that staff need to trust their supervisor and that there is a connection between this trust and job satisfaction. Staff case managers need to have a voice at work and feel empowered, and a supervisor's leadership style can influence job satisfaction and retention in their staff.

  7. Case Study Research Methodology

    Directory of Open Access Journals (Sweden)

    Mark Widdowson

    2011-01-01

    Full Text Available Commenting on the lack of case studies published in modern psychotherapy publications, the author reviews the strengths of case study methodology and responds to common criticisms, before providing a summary of types of case studies including clinical, experimental and naturalistic. Suggestions are included for developing systematic case studies and brief descriptions are given of a range of research resources relating to outcome and process measures. Examples of a pragmatic case study design and a hermeneutic single-case efficacy design are given and the paper concludes with some ethical considerations and an exhortation to the TA community to engage more widely in case study research.

  8. Case report

    African Journals Online (AJOL)

    abp

    2015-08-31

    Aug 31, 2015 ... Dual intersection syndrome of the forearm: a case report. Bouchra Zhari1,& ... We reported a case of a 60-year-old man presented to our formation with painful swelling on .... With a fiddling clinical observation and diagnosis.

  9. Case-positive versus case-negative designs for low-rate lithium thionyl chloride cells

    Science.gov (United States)

    Mahy, T. X.

    1982-03-01

    Case polarity design choices are discussed. Two examples of case-negative designs are presented. One battery is thionyl chloride limited and the other is lithium limited. The case-positive design is thionyl chloride limited. It is found that the case-positive/case-negative design consideration does not seem to have much bearing on storage. However, during low rate discharge, the case-negative cells show a steadily decreasing capacity as you go to lower and lower rates.

  10. CASE REPORT CASE CASE Conned by Conn's syndrome

    African Journals Online (AJOL)

    2008-01-08

    Jan 8, 2008 ... ing of the aldosterone-producing adenoma (APA) can prove challenging but is nonetheless very important for surgical planning and cure. We present two patients with MRI (magnetic resonance imaging) confirma- tion of APA with negative and equivocal CT (computed tomography) scans. Case 1.

  11. 40 CFR 63.53 - Application content for case-by-case MACT determinations.

    Science.gov (United States)

    2010-07-01

    ... consistent with § 63.52(f). The owner or operator may recommend a specific design, equipment, work practice... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Application content for case-by-case... Act Sections, Sections 112(g) and 112(j) § 63.53 Application content for case-by-case MACT...

  12. case series

    African Journals Online (AJOL)

    Administrator

    Key words: Case report, case series, concept analysis, research design. African Health Sciences 2012; (4): 557 - 562 http://dx.doi.org/10.4314/ahs.v12i4.25. PO Box 17666 .... According to the latest version of the Dictionary of. Epidemiology ...

  13. Case series

    African Journals Online (AJOL)

    abp

    30 mai 2017 ... All patients underwent systematic plaster immobilization for a period of ... On average, nails were removed after about 6 ... cases), osteitis associated with material (2 cases), refracture (3 ... Although intramedullary nailing ideally is an osteosynthesis ..... intramedullary fixation of pediatric forearm fractures.

  14. Fingerprints in the Great Basin: The Nellis Air Force Base Regional Obsidian Sourcing Study

    Science.gov (United States)

    2005-01-01

    disturbance from the fed- ware made up 14 percent, and Virgin- Kayenta eral action proposed for the project area, the sites Pueblo wares, 12 percent. Only seven...Virgin- Kayenta Pueblo). Most ceramics (53 per- retrieved from two small, temporary camps. Site cent) were found in Unit V, where wares manu...Parowan Fremont wares unearthed from the sites included projectile were predominant (85 percent). Virgin- Kayenta points, drills, bifaces, and

  15. Improving Casing Integrity by Induction Brazing of Casing Connections

    NARCIS (Netherlands)

    Ernens, Dennis; Hariharan, Hari; van Haaften, Willem Maarten; Pasaribu, Rihard; Jabs, Matthew; McKim, Richard

    2017-01-01

    Brazing technology allows metallurgical joining of dissimilar materials using a filler material. In this paper brazing technology applied to casing connections is presented. The initial application was triggered by challenges with mechanical and pressure integrity after expansion of casing

  16. Case-based reasoning

    CERN Document Server

    Kolodner, Janet

    1993-01-01

    Case-based reasoning is one of the fastest growing areas in the field of knowledge-based systems and this book, authored by a leader in the field, is the first comprehensive text on the subject. Case-based reasoning systems are systems that store information about situations in their memory. As new problems arise, similar situations are searched out to help solve these problems. Problems are understood and inferences are made by finding the closest cases in memory, comparing and contrasting the problem with those cases, making inferences based on those comparisons, and asking questions whe

  17. Codification of Some Usage Cases of Lithuanian Language Cases and Prepositions

    Directory of Open Access Journals (Sweden)

    Vidas Valskys

    2013-12-01

    Full Text Available The present article is related to analysing several cases of the relationship between usage of cases and prepositions with the norms indicated in the syntax booklet “Language Advice”. The article is a discussion regarding some normative evaluation aspects regarding the usage of the preposition “greta” (next to having the meaning of exception (exclusion, usage of the adjectivised instrumental case in constructions with the verb “(pavirsti” (to turn, to become, to grow, to get and some cases of the postposition “dėka” (with the help of. Utmost attention is paid to discussion of (nonnormative evaluation of some constructions including usage of the said cases and prepositions that are doubtful in some aspects, their presentation in normative sources and further prospects related to further codification of the said cases. The article is based on vast empirical materials: examples from the “Corpus of the Contemporary Lithuanian”, the Internet and other texts related to contemporary usage.

  18. Case Report

    African Journals Online (AJOL)

    Sarra

    failure and/or per vaginum (PV) leaN of dialysate. Case report: A ... had PV leaN of the dialysate that was misinterpreted by the .... as part of the management of this infection. On the .... case, we believe that laparoscopy represents a good tool.

  19. Clinical cases

    International Nuclear Information System (INIS)

    Servente, L.

    2012-01-01

    This presentation is about clinical cases and the contribution of the PET - CT Fag application in the diagnosis and treatment of different types of cancer. The cases presented were: neck diseases, epidermoid carcinoma, liver damage and metastasize, lymphoma, thrombosis, colonic cancer and lung disease

  20. Dermatology case

    Directory of Open Access Journals (Sweden)

    Catarina Lacerda

    2017-11-01

    Full Text Available Aims: To report a case of uncharacteristic presentation of Parvovirus B19. This virus causes some atypical cutaneous rash such as papular-purpuric “gloves and socks” syndrome which is a rare entity, self-limited and resolves spontaneously to cure. Case Report: Authors describe a case of a six-year-old boy who went to the Emergency Department with a cutaneous rash initially on a finger and then mouth, hands and feet followed by fever. He fully recovered without sequelae. Conclusions: It is important to consider this agent as a possible responsible for atypical purpuric rash.

  1. Contemplating case mix: A primer on case mix classification and management.

    Science.gov (United States)

    Costa, Andrew P; Poss, Jeffery W; McKillop, Ian

    2015-01-01

    Case mix classifications are the frameworks that underlie many healthcare funding schemes, including the so-called activity-based funding. Now more than ever, Canadian healthcare administrators are evaluating case mix-based funding and deciphering how they will influence their organization. Case mix is a topic fraught with technical jargon and largely relegated to government agencies or private industries. This article provides an abridged review of case mix classification as well as its implications for management in healthcare. © 2015 The Canadian College of Health Leaders.

  2. Impact of lens case hygiene guidelines on contact lens case contamination.

    Science.gov (United States)

    Wu, Yvonne T; Teng, Yuu Juan; Nicholas, Mary; Harmis, Najat; Zhu, Hua; Willcox, Mark D P; Stapleton, Fiona

    2011-10-01

    Lens case contamination is a risk factor for microbial keratitis. The effectiveness of manufacturers' lens case cleaning guidelines in limiting microbial contamination has not been evaluated in vivo. This study compared the effectiveness of manufacturers' guidelines and an alternative cleaning regimen. A randomized cross-over clinical trial with two phases (n = 40) was performed. Participants used the lens types of their choice in conjunction with the provided multipurpose solution (containing polyhexamethylene biguanide) for daily wear. In the manufacturers' guideline phase, cases were rinsed with multipurpose solution and air dried. In the alternative regimen phase, cases were rubbed, rinsed with solution, tissue wiped, and air-dried face down. The duration of each phase was 1 month. Lens cases were collected at the end of each phase for microbiological investigation. The levels of microbial contamination were compared, and compliance to both regimens was assessed. The case contamination rate was 82% (32/39) in the manufacturers' guideline group, compared with 72% (28/39) in the alternative regimen group. There were significantly fewer (p = 0.004) colony forming units (CFU) of bacteria from cases used by following the alternative regimen (CFU range of 0 to 10, and median of 12 CFU per well) compared with that of the manufacturer's guidelines (CFU range of 0 to 10, and median of 28 CFU per well). The compliance level between both guidelines was not significantly different (p > 0.05). The alternative guidelines are more effective in eliminating microbial contamination from lens cases than that of the current manufacturer's guideline. Simply incorporating rubbing and tissue-wiping steps in daily case hygiene reduces viable organism contamination.

  3. Case report

    African Journals Online (AJOL)

    abp

    8 mai 2013 ... subsequent conception and placenta accreta: a case report. American Journal of Obstetrics and Gynecology. September. 2012; 207(3 ) : e7-e8. PubMed | Google Scholar. 5. Umashankar T, Patted S, Handigund R. Endometrial osseous metaplasia: Clinicopathological study of a case and literature review.

  4. Case report

    African Journals Online (AJOL)

    ebutamanya

    2015-12-04

    Dec 4, 2015 ... was made, while maintaining of valproic acid and clonazepam.This combination allowed a partial remission, allowing a best level of adaptation, it has been maintained. The clozapine has not been tried in this case. Discussion. This case illustrates the presentation of Schizophrenia characterized.

  5. CASE STUDY

    African Journals Online (AJOL)

    HIV infection has several oral manifestations, including oral candidiasis and oral hairy leucoplakia. Occasionally unusual presentations requiring rigorous investigations are seen, and in these cases the diagnosis sometimes remains a dilemma owing to limited investigation facilities.1-3 We present the case of a patient who.

  6. Case Report

    African Journals Online (AJOL)

    the kidney could still be transplanted successfully. We describe a case of high ureteric injury during multi-organ recovery and successful implantation using a Boari flap ureterocystostomy. Case Report. The donor kidney was procured from a 55-year-old male brain stem deceased donor following intra-cerebral hemorrhage.

  7. Case report

    African Journals Online (AJOL)

    abp

    2016-02-08

    Feb 8, 2016 ... pituitary metastases can be characteristic and evocative but in no case pathognomic. The diabetes insipidus is the most common clinical manifestation of the disease [2, 3]. We report herein a case of an acute adrenal insufficiency revealing pituitary metastases of lung cancer. Patient and observation.

  8. Case report

    African Journals Online (AJOL)

    abp

    2015-08-13

    Aug 13, 2015 ... Middle East, Mediterranean region, Central Europe, Australia and. South America) [1, 2]. The incidence of musculoskeletal echinococcosis including involvement of subcutaneous tissue is 1%-. 5.4% among all cases of hydatid disease [2]. In this report, we present a case of recurrent hydatid cysts involving ...

  9. [Case and studies].

    Science.gov (United States)

    Schubert, András

    2015-11-15

    Case studies and case reports form an important and ever growing part of scientific and scholarly literature. The paper deals with the share and citation rate of these publication types on different fields of research. In general, evidence seems to support the opinion that an excessive number of such publications may negatively influence the impact factor of the journal. In the literature of scientometrics, case studies (at least the presence of the term "case study" in the titles of the papers) have a moderate share, but their citation rate is practically equal to that of other publication types.

  10. No case for Case in locality: Case does not help interpretation when intervention blocks A-bar chains

    Directory of Open Access Journals (Sweden)

    Naama Friedmann

    2017-04-01

    Full Text Available We discuss a robust yet at first sight surprising fact: individuals who have problems understanding sentences with object A-bar movement cannot use overt Case marking of the object to interpret these sentences and to associate the DPs with thematic roles. We tested the effect of overt Case marking of the object in typically developing Hebrew-speaking children by comparing their comprehension of 'which 'object questions with and without the object Case marker 'et', and found that there was no difference in comprehension between the two. A similar pattern was found in an adolescent with syntactic SLI. We then tested the comprehension of object topicalized structures in the order OVS, where the only element identifying these sentences as object-first sentences and distinguishing them from simple SVO sentences was the object marker. We tested this in three populations with object A-bar movement problems: individuals with agrammatism, adolescents with syntactic SLI, and orally-trained children with hearing impairment, as well as in analysis of previous data on typically-developing children acquiring Hebrew. All populations failed to understand the sentence, but did not consistently reverse the thematic roles of the two noun phrases. This suggests that they were sensitive to the presence of the Case marker but could not use it for interpretation. We argue that these findings immediately follow from the way intervention and locality are computed, under the featural Relativized Minimality approach. Case is not among the features triggering movement, therefore a Case difference is not taken into account in trying to build a movement chain across an intervener. As a result, the object chain cannot be built across the intervening subject in the relevant cases, and overt Case marking of the object cannot help rescue the structure. Thematic role assignment in complex movement configurations requires the building of movement chains; if chain formation fails

  11. Case Study: Puttin' on the Ritz: How to Put Science into Cases

    Science.gov (United States)

    Herreid, Clyde Freeman

    2017-01-01

    There are multiple ways to put science into a case. This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. This month's issue discusses different ways of presenting science in case studies.

  12. Case series

    African Journals Online (AJOL)

    ebutamanya

    2016-04-27

    Apr 27, 2016 ... Laparoscopic surgery for groin hernia in a third world country: a report of 9 cases of ... Concerning mesh repair, the (open) LICHENSTEIN and laparoscopic inguinal hernia techniques are ... Two cases were bilateral, 5 unilateral and all of them primary. ... In Africa, This approach is still marginal; few studies.

  13. Case law

    International Nuclear Information System (INIS)

    2016-01-01

    This section treats of the following case laws: 1 - Case Law France: Conseil d'etat decision, 22 February 2016, EDF v. Republic and Canton of Geneva relative to the Bugey nuclear power plant (No. 373516); United States: Brodsky v. US Nuclear Regulatory Commission, 650 Fed. Appx. 804 (2. Cir. 2016)

  14. Case-by-Case Adjudication and the Path of the Law

    OpenAIRE

    Anthony Niblett

    2013-01-01

    This paper presents a model of judging, illustrating how case law evolves when two types of judges with different policy preferences decide cases narrowly. The model shows that case law is unlikely to reflect the midpoint of the judges' ideal points. The result challenges the conventional wisdom suggesting that balancing ideologically extreme judges will likely yield moderate laws. The model suggests that a centrist executive faced with a sitting extreme left-wing judge should appoint a moder...

  15. Teaching Business French through Case Studies: Presentation of a Marketing Case.

    Science.gov (United States)

    Federico, Salvatore; Moore, Catherine

    The use of case studies as a means for teaching business French is discussed. The approach is advocated because of the realism of case studies, which are based on actual occurrences. Characteristics of a good case are noted: it tells a story, focuses on interest-arousing issues, is set in the past 10 years, permits empathy with the main…

  16. Cases. Assisted suicide in The Netherlands : The Chabot Case

    NARCIS (Netherlands)

    Griffiths, John

    1995-01-01

    In earlier decisions the Dutch Supreme Court has recognised a defence of 'necessity," under narrowly-defined circumstances, to a charge of performing euthanasia.2 Its most recent decision deals with assistance with suicide in the case of a person whose suffering is not of somatic origin. The case is

  17. Excavations at Kainapirina (SAC), Watom Island, Papua New Guinea

    International Nuclear Information System (INIS)

    Green, R.C.; Anson, D.

    1998-01-01

    This paper is the final report on excavations in 1985 at the locality of Kainapirina (site SAC), situated on the Reber mission station adjacent to Rakival village on Watom Island. It backgrounds previous investigations there, the objectives of the 1985 endeavours, and the excavation strategies undertaken to achieve them. The occupation sequence based on stratigraphy, dating, and associated structural features is described and illustrated. Aspects of the human skeletal remains recovered are briefly reviewed; the economic evidence is discussed in detail. Analyses are provided of the various portable artefacts from these Lapita contexts, particularly stone adzes. obsidian, and pottery. These document an 'exotic to Watom' exchange component among the local manufactures. It is concluded that these 1985 excavations at SAC currently best enable an understanding of the significance of the entire Reber-Rakival Lapita site. (author)

  18. Assembling a Case Study Tool Kit: 10 Tools for Teaching with Cases

    Science.gov (United States)

    Prud'homme-Généreux, Annie

    2017-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. The author shares the strategies and tools that teachers can use to manage a case study classroom effectively.

  19. Case report

    African Journals Online (AJOL)

    ebutamanya

    28 août 2015 ... (intra-osseous synovial cyst) Clinical and therapeutic aspect: case report. Chir Main. 2009 Feb; 28(1):37-41. PubMed |. Google Scholar. 10. Chantelot C, Laffargue P, Masmejean E, Peltier B, Barouk P,. Fontaine C. Fracture of the scaphoid carpal bone secondary to an intraosseous cyst: apropos of a case.

  20. Case report

    African Journals Online (AJOL)

    ebutamanya

    2015-01-21

    Jan 21, 2015 ... Published in partnership with the African Field Epidemiology Network (AFENET). (www.afenet.net). Case report. Open Access ... La quantité de tissu neural immature permet d'établir une classification .... Wu X, Han LY, Xu X, Li Z. Recurrent immature teratoma of the ovary: a case report of radical secondary ...

  1. Case report

    African Journals Online (AJOL)

    ebutamanya

    2015-10-09

    Oct 9, 2015 ... Aguas SC, Quarracino MC, Lence AN, Lanfranchi-Tizeira HE. Primary melanoma of the oral cavity: ten cases and review of. 177 cases from literature. Medicina oral, patologia oral y cirugia bucal. 2009;14(6):E265-71. PubMed | Google. Scholar. 6. Rapidis AD, Apostolidis C, Vilos G, Valsamis S. Primary.

  2. Case series

    African Journals Online (AJOL)

    abp

    2017-07-13

    Jul 13, 2017 ... Its purpose is to assess the clinical and ... Other circumstances of discovery were atrial fibrillation, ... ventricular pacing (9.1%) and blood pressure intolerance to stress ... The mitral flow was a ... anterior mitral valve's pillar was found in one case with a left ... with a stop at the first level in another case.

  3. Clinical case

    International Nuclear Information System (INIS)

    Garcia Fontes, M

    2012-01-01

    This presentation is about a case of a patient with liver tumor. The ultrasound scan and Tc technique were used for the diagnosis and treatment. The application of PET - CT FDG contributed to detect peripheral cholangiocarcinoma, the lymph node distance to guide the therapeutic and the recurrence in case of a negative morphological methods.

  4. Case Study: A Picture Worth a Thousand Words? Making a Case for Video Case Studies

    Science.gov (United States)

    Pai, Aditi

    2014-01-01

    A picture, they say, is worth a thousand words. If a mere picture is worth a thousand words, how much more are "moving pictures" or videos worth? The author poses this not merely as a rhetorical question, but because she wishes to make a case for using videos in the traditional case study method. She recommends four main approaches of…

  5. Case report

    African Journals Online (AJOL)

    raoul

    2011-10-20

    Oct 20, 2011 ... Abstract. A 22-year old man was bitten by a snake on his scrotum. This interesting and unusual case occurred in the rural area of District Aligarh, India. The uniqueness of the case lies in the fact that scrotum is an extremely rare and unusual site for snake bite. Further, with negligible local signs of.

  6. Teaching Case: MiHotel--Applicant Processing System Design Case

    Science.gov (United States)

    Miller, Robert E.; Dunn, Paul

    2018-01-01

    This teaching case describes the functionality of an applicant processing system designed for a fictitious hotel chain. The system detailed in the case includes a webform where applicants complete and submit job applications. The system also includes a desktop application used by hotel managers and Human Resources to track applications and process…

  7. Eight cases of parapharyngeal space tumor. Case reports and MRI diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Takagi, Setsuo; Yoshimura, Tadashi; Tanaka, Katsuhiko

    1988-03-01

    Between 1977 and 1987, 8 cases of parapharyngeal space tumor (2 cases of pleomorphic adenoma, and schwannoma, respectively, a case of neurofibroma, neuroblastoma, retension cyst and branchial cleft cyst) were treated in our clinic. There were 4 males and 4 females. This papar reports these cases and discusses the availability of MRI diagnosis. We consider that the x-ray CT is presently most useful for the parapharyngeal space tumor. However, MRI imaged tumor clearly without bone artifacts such as recognized in x-ray CT, and be able to take a information of tumor vascularity. So that MRI is very useful for diagnosis of parapharyngeal space tumor.

  8. Clinical Case Registries (CCR)

    Data.gov (United States)

    Department of Veterans Affairs — The Clinical Case Registries (CCR) replaced the former Immunology Case Registry and the Hepatitis C Case Registry with local and national databases. The CCR:HIV and...

  9. Delusional Parasitosis : Series Of 25 Cases

    Directory of Open Access Journals (Sweden)

    Bhatia M S

    1996-01-01

    Full Text Available A series 25 cases of delusional parasitosis is being reported. There were three cases below 45 years, 12 cases between 46-45 years and 11 cases above 55 years of age, 64% cases were females. A majority of cases (92% had insidious onset. The duration of symptoms in all the cases (except one was 6 months or more. 13 cases presented with infestation with insects over body and 10 cases with insects crawling over scalp. There were three cases each with diabetes mellitus and leprosy. Three cased had dementia, 2 cases had depression and one case presented with trichotillomania. Pimozide was used in22 cases, amitriptyline in 2 cases and fluoxetine in one. 14 cases (52% showed complete remission while receiving drug, 8 cases showed partial improvement and 3 cases did not respond.

  10. Nurse Case Managers' Experiences on Case Management for Long-term Hospitalization in Korea

    Directory of Open Access Journals (Sweden)

    Jinjoo Oh, Ph.D., RN, GNP

    2017-12-01

    Full Text Available Purpose: The implementation of case management for long-term hospitalization use has been approved for controlling medical cost increases in other countries. But, introduction of the case management in Korea has created issues that hinder its effective operation. This qualitative study aimed to obtain further understanding of the issues surrounding the management of Medical Aid beneficiaries' use of long-term hospitalization from the case managers' perspectives and to provide suggestions for successful case management. Methods: Thematic analysis was employed to analyze the data. Medical Aid case managers with 3 or more years of case management experience were recruited from urban, suburban, and rural regions. Data were collected through in-depth interviews: 12 nurse case managers participated in focus group interviews and 11 participated in individual one-on-one interviews. Results: Four major themes emerged: on-site obstacles that hinder work progress; going in an opposite direction; ambiguous position of case managers; and work-related emotions. Eleven subthemes were discovered: chasing potential candidates; becoming an enemy; discharging patients who have nowhere to go; welfare-centered national policies increasing medical costs; Medical Aid Program that encourages hospitalization; misuse of hospitalization; feeling limited; working without authority; fulfilling the expected role; fretting about social criticism; and feeling neglected and unprotected. Conclusion: The findings highlight the complexity and ambiguity of the issues faced by case managers. Successful management of Medical Aid resources requires the orchestrated efforts and collaboration of multiple stakeholders. More systematized support and resources for nurse case managers are essential to fully implement this nursing innovation in Korea. Keywords: case management, focus groups, hospitalization, qualitative research, vulnerable populations

  11. PSS Case Book

    DEFF Research Database (Denmark)

    Neugebauer, Line Maria; Mougaard, Krestine; Andersen, Jakob Bejbro

    The transformation process towards a PSS-oriented company is describes, through the presentation of the best practice cases. Each case describes motivations, challenges, business models and PSS offerings....

  12. Case law

    International Nuclear Information System (INIS)

    2015-01-01

    This section treats of the two following case laws: Slovak Republic: Further developments in cases related to the challenge by Greenpeace Slovakia to the Mochovce nuclear power plant; United States: Judgment of the Nuclear Regulatory Commission denying requests from petitioners to suspend final reactor licensing decisions pending the issuance of a final determination of reasonable assurance of permanent disposal of spent fuel

  13. Mining with Rare Cases

    Science.gov (United States)

    Weiss, Gary M.

    Rare cases are often the most interesting cases. For example, in medical diagnosis one is typically interested in identifying relatively rare diseases, such as cancer, rather than more frequently occurring ones, such as the common cold. In this chapter we discuss the role of rare cases in Data Mining. Specific problems associated with mining rare cases are discussed, followed by a description of methods for addressing these problems.

  14. Case series: Two cases of eyeball tattoos with short-term complications.

    Science.gov (United States)

    Duarte, Gonzalo; Cheja, Rashel; Pachón, Diana; Ramírez, Carolina; Arellanes, Lourdes

    2017-04-01

    To report two cases of eyeball tattoos with short-term post procedural complications. Case 1 is a 26-year-old Mexican man that developed orbital cellulitis and posterior scleritis 2 h after an eyeball tattoo. Patient responded satisfactorily to systemic antibiotic and corticosteroid treatment. Case 2 is a 17-year-old Mexican man that developed two sub-episcleral nodules in the ink injection sites immediately after the procedure. Eyeball tattoos are performed by non-ophthalmic trained personnel. There are a substantial number of short-term risks associated with this procedure. Long-term effects on the eyes and vision are still unknown, but in a worst case scenario could include loss of vision or permanent damage to the eyes.

  15. Nurse Case Managers' Experiences on Case Management for Long-term Hospitalization in Korea.

    Science.gov (United States)

    Oh, Jinjoo; Oh, Seieun

    2017-12-01

    The implementation of case management for long-term hospitalization use has been approved for controlling medical cost increases in other countries. But, introduction of the case management in Korea has created issues that hinder its effective operation. This qualitative study aimed to obtain further understanding of the issues surrounding the management of Medical Aid beneficiaries' use of long-term hospitalization from the case managers' perspectives and to provide suggestions for successful case management. Thematic analysis was employed to analyze the data. Medical Aid case managers with 3 or more years of case management experience were recruited from urban, suburban, and rural regions. Data were collected through in-depth interviews: 12 nurse case managers participated in focus group interviews and 11 participated in individual one-on-one interviews. Four major themes emerged: on-site obstacles that hinder work progress; going in an opposite direction; ambiguous position of case managers; and work-related emotions. Eleven subthemes were discovered: chasing potential candidates; becoming an enemy; discharging patients who have nowhere to go; welfare-centered national policies increasing medical costs; Medical Aid Program that encourages hospitalization; misuse of hospitalization; feeling limited; working without authority; fulfilling the expected role; fretting about social criticism; and feeling neglected and unprotected. The findings highlight the complexity and ambiguity of the issues faced by case managers. Successful management of Medical Aid resources requires the orchestrated efforts and collaboration of multiple stakeholders. More systematized support and resources for nurse case managers are essential to fully implement this nursing innovation in Korea. Copyright © 2017. Published by Elsevier B.V.

  16. Building theories from case study research: the progressive case study

    NARCIS (Netherlands)

    Steenhuis, H.J.; de Bruijn, E.J.

    2006-01-01

    Meredith (1998) argues for more case and field research studies in the field of operations management. Based on a literature review, we discuss several existing approaches to case studies and their characteristics. These approaches include; the Grounded Theory approach which proposes no prior

  17. Case-Based Fault Diagnostic System

    International Nuclear Information System (INIS)

    Mohamed, A.H.

    2014-01-01

    Nowadays, case-based fault diagnostic (CBFD) systems have become important and widely applied problem solving technologies. They are based on the assumption that “similar faults have similar diagnosis”. On the other hand, CBFD systems still suffer from some limitations. Common ones of them are: (1) failure of CBFD to have the needed diagnosis for the new faults that have no similar cases in the case library. (2) Limited memorization when increasing the number of stored cases in the library. The proposed research introduces incorporating the neural network into the case based system to enable the system to diagnose all the faults. Neural networks have proved their success in the classification and diagnosis problems. The suggested system uses the neural network to diagnose the new faults (cases) that cannot be diagnosed by the traditional CBR diagnostic system. Besides, the proposed system can use the another neural network to control adding and deleting the cases in the library to manage the size of the cases in the case library. However, the suggested system has improved the performance of the case based fault diagnostic system when applied for the motor rolling bearing as a case of study

  18. Case vignettes of movement disorders.

    Science.gov (United States)

    Yung, C Y

    1983-08-01

    This paper reports five movement disorders cases to serve as a basis for discussion of the problems encountered in the clinical management of these cases, and the pathophysiological mechanisms involved in these disorders as presented. Case 1 is a description of the subjective experience of a patient with acute orofacial dystonia from promethazine. Case 2 is the use of clonazepam is post-head injury tics. Case 3 is the complication from discontinuation of haloperidol and benztropine mesylate treatment. Case 4 is myoclonus in subacute sclerosing Panencephalitis, and Case 5 is rebound tremor from withdrawal of a beta-adrenergic blocker.

  19. Case series

    African Journals Online (AJOL)

    abp

    7 avr. 2016 ... HTA were complicated by heart disease in 24% of cases and by renal disease in 20% of cases ... of clinical specificity. It is not unusual for HTA to be the only manifestation of the disease. In our study we .... Le syndrome de Cushing reste une cause rare d'HTA, sa prévalence dans des centres spécialisés en ...

  20. Is case-chaos methodology an appropriate alternative to conventional case-control studies for investigating outbreaks?

    Science.gov (United States)

    Edelstein, Michael; Wallensten, Anders; Kühlmann-Berenzon, Sharon

    2014-08-15

    Case-chaos methodology is a proposed alternative to case-control studies that simulates controls by randomly reshuffling the exposures of cases. We evaluated the method using data on outbreaks in Sweden. We identified 5 case-control studies from foodborne illness outbreaks that occurred between 2005 and 2012. Using case-chaos methodology, we calculated odds ratios 1,000 times for each exposure. We used the median as the point estimate and the 2.5th and 97.5th percentiles as the confidence interval. We compared case-chaos matched odds ratios with their respective case-control odds ratios in terms of statistical significance. Using Spearman's correlation, we estimated the correlation between matched odds ratios and the proportion of cases exposed to each exposure and quantified the relationship between the 2 using a normal linear mixed model. Each case-control study identified an outbreak vehicle (odds ratios = 4.9-45). Case-chaos methodology identified the outbreak vehicle 3 out of 5 times. It identified significant associations in 22 of 113 exposures that were not associated with outcome and 5 of 18 exposures that were significantly associated with outcome. Log matched odds ratios correlated with their respective proportion of cases exposed (Spearman ρ = 0.91) and increased significantly with the proportion of cases exposed (b = 0.054). Case-chaos methodology missed the outbreak source 2 of 5 times and identified spurious associations between a number of exposures and outcome. Measures of association correlated with the proportion of cases exposed. We recommended against using case-chaos analysis during outbreak investigations. © The Author 2014. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Twelve cases of multiple myeloma in Nagasaki (especially seven atomic bombing casualty cases). [In Japanese

    Energy Technology Data Exchange (ETDEWEB)

    Ichimaru, M; Yasuhi, S; Ouchuru, S

    1963-12-01

    Since 1958, there have been 12 cases of multiple myeloma in Nagasaki, and among them were 7 cases representing atomic bombing casualties, with 3 cases being with 2 km distance from the hypocenter. The age of onset was between 51 and 69 years, and the sex ratio was 8:4, it occurring mostly in males. Symptoms were predominantly low back pain and chest pain caused by the bone changes in 8 cases. Two cases complained of general malaise and palpitation which resulted from anemia. One developed persistent epistaris, and another complained of diplopia caused by the paralysis of the oculomotor nerve. Peripheral blood in all cases showed anemia, 9 with hyperchromic and 3 with normochromic or hypochromic anemia. Low platelet counts were seen in 3 cases. All showed leukopenia. All cases showed typical ..gamma..-globulin change with a myeloma peak, and in 4 cases showed an increase of ..beta..-globulin. Bence-Jones proteinuria was present in 5 cases. Average course was 1 year 4 months. Among complications, myeloma nephrosis, aplastic anemia, and pneumonia were the most important ones.

  2. Final report on case studies

    DEFF Research Database (Denmark)

    Ljungberg, Daniel; McKelvey, Maureen; Lassen, Astrid Heidemann

    2012-01-01

    Case study as a research design means investigating a single or multiple instance(s) or setting(s) (i.e. a case) and its entire context to explain a phenomenon and its processes. This is achieved through detailed understanding, usually comprised of multiple sources of information. In this way, case...... studies attempt to provide as a complete an understanding of a (complex) phenomenon as possible. Within the AEGIS project, survey and case study research are complementary. They are complementary in the sense that the former can provide more generalizable evidence on a phenomenon in terms of cross......-sectional data, while the latter can provide more in-depth (qualitative) understanding on specific issues. In systematically examining the case studies, however, this report goes beyond a typical single case study. Here we provide a synthesis of 86 case studies. Multiple case studies, following similar focus...

  3. Psychotherapy trainees' multicultural case conceptualization content: thematic differences across three cases.

    Science.gov (United States)

    Lee, Debbiesiu L; Sheridan, Daniel J; Rosen, Adam D; Jones, Isaiah

    2013-06-01

    This study examined thematic differences in the multicultural case conceptualization content of 61 psychotherapy trainees across three different cases and trainee demographics (number of multicultural courses completed, years of supervised clinical practicum completed, and White trainee vs. trainee of color). Themes across cases included general counseling skills (attend to affect, build rapport, focus on specific client concerns, use of specific clinical interventions, and use of external resources not related to culture), as well as multicultural specific counseling skills (focus on culture, focus on discrimination, use of culturally competent interventions, and use of external resources related to culture). Thematic differences across case were found in three of the nine themes (affect, culture, discrimination). No systematic differences were found across multicultural training, clinical training, or race. Implications of these results are discussed.

  4. Defining a periodontitis case

    DEFF Research Database (Denmark)

    Baelum, Vibeke; Lopez, Rodrigo

    2012-01-01

    . Conclusions The results indicate that it should be feasible for the periodontal community to reach an agreement over the distinction between a case and a non-case. The classification system proposed by van der Velden is better suited for providing clinicians with a clear image of the case....

  5. Leveraging tuberculosis case relative locations to enhance case detection and linkage to care in Swaziland.

    Science.gov (United States)

    Brunetti, Marie; Rajasekharan, Sathyanath; Ustero, Piluca; Ngo, Katherine; Sikhondze, Welile; Mzileni, Buli; Mandalakas, Anna; Kay, Alexander W

    2018-01-01

    In Swaziland, as in many high HIV/TB burden settings, there is not information available regarding the household location of TB cases for identifying areas of increased TB incidence, limiting the development of targeted interventions. Data from "Butimba", a TB REACH active case finding project, was re-analyzed to provide insight into the location of TB cases surrounding Mbabane, Swaziland. The project aimed to identify geographical areas with high TB burdens to inform active case finding efforts. Butimba implemented household contact tracing; obtaining landmark based, informal directions, to index case homes, defined here as relative locations. The relative locations were matched to census enumeration areas (known location reference areas) using the Microsoft Excel Fuzzy Lookup function. Of 403 relative locations, an enumeration area reference was detected in 388 (96%). TB cases in each census enumeration area and the active case finders in each Tinkhundla, a local governmental region, were mapped using the geographic information system, QGIS 2.16. Urban Tinkhundla predictably accounted for most cases; however, after adjusting for population, the highest density of cases was found in rural Tinkhundla. There was no correlation between the number of active case finders currently assigned to the 7 Tinkhundla surrounding Mbabane and the total number of TB cases (Spearman rho = -0.57, p  = 0.17) or the population adjusted TB cases (Spearman rho = 0.14, p  = 0.75) per Tinkhundla. Reducing TB incidence in high-burden settings demands novel analytic approaches to study TB case locations. We demonstrated the feasibility of linking relative locations to more precise geographical areas, enabling data-driven guidance for National Tuberculosis Programs' resource allocation. In collaboration with the Swazi National Tuberculosis Control Program, this analysis highlighted opportunities to better align the active case finding national strategy with the TB disease

  6. Case Management Directors

    Science.gov (United States)

    Bankston White, Cheri; Birmingham, Jackie

    2015-01-01

    Purpose and Objectives: Case management directors are in a dynamic position to affect the transition of care of patients across the continuum, work with all levels of providers, and support the financial well-being of a hospital. Most importantly, they can drive good patient outcomes. Although the position is critical on many different levels, there is little to help guide a new director in attending to all the “moving parts” of such a complex role. This is Part 2 of a two-part article written for case management directors, particularly new ones. Part 1 covered the first 4 of 7 tracks: (1) Staffing and Human Resources, (2) Compliance and Accreditation, (3) Discharge Planning and (4) Utilization Review and Revenue Cycle. Part 2 addresses (5) Internal Departmental Relationships (Organizational), (6) External Relationships (Community Agency), and (7) Quality and Program Outcomes. This article attempts to answer the following questions: Are case management directors prepared for an expanded role that affects departments and organizations outside of their own?How does a case management director manage the transition of care of patients while managing required relationships outside the department?How does the director manage program outcomes in such a complex department? Primary Practice Setting: The information is most meaningful to those case management directors who work in either stand-alone hospitals or integrated health systems and have frontline case managers (CMs) reporting to them. Findings/Conclusions: Part 1 found that case management directors would benefit from further research and documentation of “best practices” related to their role, particularly in the areas of leadership and management. The same conclusion applies to Part 2, which addresses the director's responsibilities outside her immediate department. Leadership and management skills apply as well to building strong, productive relationships across a broad spectrum of external organizations

  7. CASE REPORT CASE A super 'lead pipe' colon: radio-pathological ...

    African Journals Online (AJOL)

    2008-10-15

    Oct 15, 2008 ... cancer in UC. Clearly, correct diagnosis is crucial. Our case not only had severe findings and a diagnosis that predated her surgery, but also had no clinical, radiological or histological features of the other alternative diagnoses. The case demonstrates an unusually severe form of 'lead pipe' colon occurring ...

  8. High laboratory cost predicted per tuberculosis case diagnosed with increased case finding without a triage strategy.

    Science.gov (United States)

    Dunbar, R; Naidoo, P; Beyers, N; Langley, I

    2017-09-01

    Cape Town, South Africa. To model the effects of increased case finding and triage strategies on laboratory costs per tuberculosis (TB) case diagnosed. We used a validated operational model and published laboratory cost data. We modelled the effect of varying the proportion with TB among presumptive cases and Xpert cartridge price reductions on cost per TB case and per additional TB case diagnosed in the Xpert-based vs. smear/culture-based algorithms. In our current scenario (18.3% with TB among presumptive cases), the proportion of cases diagnosed increased by 8.7% (16.7% vs. 15.0%), and the cost per case diagnosed increased by 142% (US$121 vs. US$50). The cost per additional case diagnosed was US$986. This would increase to US$1619 if the proportion with TB among presumptive cases was 10.6%. At 25.9-30.8% of TB prevalence among presumptive cases and a 50% reduction in Xpert cartridge price, the cost per TB case diagnosed would range from US$50 to US$59 (comparable to the US$48.77 found in routine practice with smear/culture). The operational model illustrates the effect of increased case finding on laboratory costs per TB case diagnosed. Unless triage strategies are identified, the approach will not be sustainable, even if Xpert cartridge prices are reduced.

  9. CASE REPORT Degenerative leiomyopathy CASE REPORT

    African Journals Online (AJOL)

    cases the condition was progressive and eventually affected the entire ... been discouraged because of the progressive nature of the disease. A gastrostomy and/or ... which eventually lead to their demise, usually in their late teens.4. 1.

  10. Lithic assemblages of Azokh Cave (Nagorno Karabagh, Lesser Caucasus: Raw materials, technology and regional context

    Directory of Open Access Journals (Sweden)

    Lena Asryan

    2014-03-01

    Full Text Available Azokh Cave is a Middle Pleistocene to Holocene site located in Nagorno Karabagh (Lesser Caucasus. The main entrance, Azokh 1, is a large cave that has two geological sequences (lower and upper with nine geo-archaeological units of which only the upper ones (Units I to V have a significant archaeological record.  The faunal remains and lithic artefacts in these units indicate aspects of human occupation, and exploitation of, and association with animals.     The lithic artefacts presented here were recovered from Units V, III and II during the 2002 – 2009 excavation seasons. The available chronological data indicates an age between 293 – 100 Ka for these units. The operational chain is incomplete and artefacts found in the cave are primarily end-products dominated by flake-tools. The assemblage of Unit V is composed primarily of simple, unretouched flakes with a minimal presence of retouched flakes and cores. The Unit II lithic assemblage includes a substantial Levallois component, although with fewer cores and retouched flakes. There are very few flake tools in Unit III. While it is still difficult to assign the Unit V assemblage to a techno-typological group or complex (i.e. Acheulean, Mousterian or other local techno-complexes such as the Kudarian, the Unit II assemblage is clearly associated with Mode 3 or the Mousterian techno-complex.Different local and non-local raw materials were exploited in all units for the production of lithic artefacts, although the range of raw materials is more varied in Unit II. Local chert, flint and basalt were used most commonly, probably due to their easy accessibility. Limestone, jasper and sandstone, from local and non-local sources, are present in small quantities in Units V and II. Obsidian is the only raw material that possibly originates from more distant sources. Flint and chert appear to have been preferentially exploited for flake tool production in all units, but the toolmakers show a

  11. Asynchronous asymmetric form of heterogeneous osteopetrosis: initial case expanded and a new case

    International Nuclear Information System (INIS)

    Young, L.W.; Lachman, R.S.

    2001-01-01

    We have discovered additional serial radiographs and clinical information on the initial case of ''regional osteopetrosis tarda'' that has been included in several editions of Caffey's Pediatric X-Ray Diagnosis. A definite second case was found after a search of radiology teaching files of other selected medical centers and the International Skeletal Dysplasia Registry. Analysis of the sequential unusual radiographic findings of the initial case and the equivalent compelling findings of the second case justifies renewed attention to an asynchronous asymmetric form of heterogeneous osteopetrosis. (orig.)

  12. Recent Case Law

    DEFF Research Database (Denmark)

    Petz, Thomas; Sagaert, Vincent; Østergaard, Kim

    2004-01-01

    In this section authors from various European countries report the recent case law in their country on the field of private patrimonial law, that is decisions on the law of property, juridical acts, the law of obligations, contract law and prescription. The European Review of Private Law (ERPL......) started this section in 2003. The section aims to give our readers an overview of what is happening in the most recent European case law. We have asked the national reporters to report the juridical essence of the decisions given by the highest courts in their country. These national reports...... not relate the facts of the decision, nor the personal opinion of the reporter. One can find discussions on the most important decisions of European courts in ERPL’s case note section. The recent case law section gives overviews of decisions published in periods of four months. The period of January...

  13. Case-control vaccine effectiveness studies: Preparation, design, and enrollment of cases and controls.

    Science.gov (United States)

    Verani, Jennifer R; Baqui, Abdullah H; Broome, Claire V; Cherian, Thomas; Cohen, Cheryl; Farrar, Jennifer L; Feikin, Daniel R; Groome, Michelle J; Hajjeh, Rana A; Johnson, Hope L; Madhi, Shabir A; Mulholland, Kim; O'Brien, Katherine L; Parashar, Umesh D; Patel, Manish M; Rodrigues, Laura C; Santosham, Mathuram; Scott, J Anthony; Smith, Peter G; Sommerfelt, Halvor; Tate, Jacqueline E; Victor, J Chris; Whitney, Cynthia G; Zaidi, Anita K; Zell, Elizabeth R

    2017-06-05

    Case-control studies are commonly used to evaluate effectiveness of licensed vaccines after deployment in public health programs. Such studies can provide policy-relevant data on vaccine performance under 'real world' conditions, contributing to the evidence base to support and sustain introduction of new vaccines. However, case-control studies do not measure the impact of vaccine introduction on disease at a population level, and are subject to bias and confounding, which may lead to inaccurate results that can misinform policy decisions. In 2012, a group of experts met to review recent experience with case-control studies evaluating the effectiveness of several vaccines; here we summarize the recommendations of that group regarding best practices for planning, design and enrollment of cases and controls. Rigorous planning and preparation should focus on understanding the study context including healthcare-seeking and vaccination practices. Case-control vaccine effectiveness studies are best carried out soon after vaccine introduction because high coverage creates strong potential for confounding. Endpoints specific to the vaccine target are preferable to non-specific clinical syndromes since the proportion of non-specific outcomes preventable through vaccination may vary over time and place, leading to potentially confusing results. Controls should be representative of the source population from which cases arise, and are generally recruited from the community or health facilities where cases are enrolled. Matching of controls to cases for potential confounding factors is commonly used, although should be reserved for a limited number of key variables believed to be linked to both vaccination and disease. Case-control vaccine effectiveness studies can provide information useful to guide policy decisions and vaccine development, however rigorous preparation and design is essential. Published by Elsevier Ltd.

  14. [Case management process identified from experience of nurse case managers].

    Science.gov (United States)

    Park, Eun-Jun; Kim, Chunmi

    2008-12-01

    The purpose of this study was to develop a substantive theory of case management (CM) practice by investigating the experience of nurse case managers caring for Medical Aid enrollees in Korea. A total of 12 nurses were interviewed regarding their own experience in CM practice. Data were recorded and analyzed using grounded theory. Empowerment was the core category of CM for Medical Aid enrollees. The case managers engaged in five phases as follows, phase of inquiring in advance, building a relationship with the client, giving the client critical mind, facilitating positive changes in the client's use of healthcare services, and maintaining relationship bonds. These phases moved gradually and were circular if necessary. Also, they were accelerated or slowed depending on factors including clients' characteristics, case managers' competency level, families' support level, and availability of community resources. This study helps understand what CM practice is and how nurses are performing this innovative CM role. It is recommended that nurse leaders and policy makers integrate empowerment as a core category and the five critical CM phases into future CM programs.

  15. Case-Based FCTF Reasoning System

    Directory of Open Access Journals (Sweden)

    Jing Lu

    2015-10-01

    Full Text Available Case-based reasoning uses old information to infer the answer of new problems. In case-based reasoning, a reasoner firstly records the previous cases, then searches the previous case list that is similar to the current one and uses that to solve the new case. Case-based reasoning means adapting old solving solutions to new situations. This paper proposes a reasoning system based on the case-based reasoning method. To begin, we show the theoretical structure and algorithm of from coarse to fine (FCTF reasoning system, and then demonstrate that it is possible to successfully learn and reason new information. Finally, we use our system to predict practical weather conditions based on previous ones and experiments show that the prediction accuracy increases with further learning of the FCTF reasoning system.

  16. Breast cancer case using tamoxifen during pregnancy: a case report ...

    African Journals Online (AJOL)

    This is a case of 32 years old nulliparous female who was diagnosed in November 2004 as a case of carcinoma of the right breast , luminal A , (Estrogen Receptor positive Progesterone receptor negative, Her 2 negative, Ki67 10 %), poorly differentiated invasive ductal cancer, TNM stage,T2 N0 MO. She had a wide local ...

  17. Case Study: Let's Get Personal--Putting Personality into Your Cases

    Science.gov (United States)

    Herreid, Clyde Freeman

    2017-01-01

    In this case study, the subject for discussion is the need to use teaching notes in order to add personality to case studies. Personality, it is said, is more important than policy, than demographics, than finances, or amorous peccadillos. Personality is essential. It is the interaction of people that capture our interest, yet, the question is…

  18. RSG Deployment Case Testing Results

    Energy Technology Data Exchange (ETDEWEB)

    Owsley, Stanley L.; Dodson, Michael G.; Hatchell, Brian K.; Seim, Thomas A.; Alexander, David L.; Hawthorne, Woodrow T.

    2005-09-01

    The RSG deployment case design is centered on taking the RSG system and producing a transport case that houses the RSG in a safe and controlled manner for transport. The transport case was driven by two conflicting constraints, first that the case be as light as possible, and second that it meet a stringent list of Military Specified requirements. The design team worked to extract every bit of weight from the design while striving to meet the rigorous Mil-Spec constraints. In the end compromises were made primarily on the specification side to control the overall weight of the transport case. This report outlines the case testing results.

  19. From Use Cases to Activity Cases

    DEFF Research Database (Denmark)

    Bækgaard, Lars

    2005-01-01

    Use cases can be used to capture requirements and to subdivide IT-systems into functionally coherent units. Information systems are activity systems that carry out important business activities. Many systems development methods recognize activity modeling as an important development activity. Use...

  20. Using Nondestructive Portable X-ray Fluorescence Spectrometers on Stone, Ceramics, Metals, and Other Materials in Museums: Advantages and Limitations.

    Science.gov (United States)

    Tykot, Robert H

    2016-01-01

    Elemental analysis is a fundamental method of analysis on archaeological materials to address their overall composition or identify the source of their geological components, yet having access to instrumentation, its often destructive nature, and the time and cost of analyses have limited the number and/or size of archaeological artifacts tested. The development of portable X-ray fluorescence (pXRF) instruments over the past decade, however, has allowed nondestructive analyses to be conducted in museums around the world, on virtually any size artifact, producing data for up to several hundred samples per day. Major issues have been raised, however, about the sensitivity, precision, and accuracy of these devices, and the limitation of performing surface analysis on potentially heterogeneous objects. The advantages and limitations of pXRF are discussed here regarding archaeological studies of obsidian, ceramics, metals, bone, and painted materials. © The Author(s) 2015.

  1. Late Holocene history of Chaitén Volcano: new evidence for a 17th century eruption

    Science.gov (United States)

    Lara, Luis E.; Moreno, Rodrigo; Amigo, Álvaro; Hoblitt, Richard P.; Pierson, Thomas C.

    2013-01-01

    Prior to May 2008, it was thought that the last eruption of Chaitén Volcano occurred more than 5,000 years ago, a rather long quiescent period for a volcano in such an active arc segment. However, increasingly more Holocene eruptions are being identified. This article presents both geological and historical evidence for late Holocene eruptive activity in the 17th century (AD 1625-1658), which included an explosive rhyolitic eruption that produced pumice ash fallout east of the volcano and caused channel aggradation in the Chaitén River. The extents of tephra fall and channel aggradation were similar to those of May 2008. Fine ash, pumice and obsidian fragments in the pre-2008 deposits are unequivocally derived from Chaitén Volcano. This finding has important implications for hazards assessment in the area and suggests the eruptive frequency and magnitude should be more thoroughly studied.

  2. Quaternary dating methods

    International Nuclear Information System (INIS)

    Mahaney, W.C.

    1984-01-01

    The papers in this book cover absolute, relative and multiple dating methods, and have been written by specialists from a number of different earth sciences disciplines - their common interest being the dating of geological materials within the Quaternary. Papers on absolute dating methods discuss radiocarbon, uranium-series, potassium argon, 40 Ar/ 39 Ar, paleomagnetic, obsidian hydration, thermoluminescence, amino acid racemization, tree rings, and lichenometric techniques. Those on relative dating include discussions on various geomorphic relative age indicators such as drainage density changes, hypsometric integrals, bifurcation ratios, stream junction angles, spur morphology, hillslope geometry, and till sheet characteristics. The papers on multiple dating cite examples from the Rocky Mountains, Australia, Lake Agassiz Basin, and the Southern Andes. Also included is the panel discussion which reviews and assesses the information presented, and a field trip guide which discusses the sequences of Wisconian tills and interlayered lacustrine and fluvial sediments. (orig.)

  3. Evaluating long-term performance of in situ vitrified waste forms: Methodology and results

    International Nuclear Information System (INIS)

    McGrail, B.P.; Olson, K.M.

    1992-11-01

    In situ vitrification (ISV) is an emerging technology for the remediation of hazardous and radioactive waste sites. The concept relies on the principle of Joule heating to raise the temperature of a soil between an array of electrodes above the melting temperature. After cooling, the melt solidifies into a massive glass and crystalline block similar to naturally occurring obsidian. Determining the long-term performance of ISV products in a changing regulatory environment requires a fundamental understanding of the mechanisms controlling the dissolution behavior of the material. A series of experiments was performed to determine the dissolution behavior of samples produced from the ISV processing of typical soils from the Idaho National Engineering Laboratory subsurface disposal area. Dissolution rate constant measurements were completed at 90 degrees C over the pH range 2 to 11 for one sample obtained from a field test of the ISV process

  4. Case Study: What Makes a Good Case, Revisited: The Survey Monkey Tells All

    Science.gov (United States)

    Herried, Clyde Freeman; Prud'homme-Genereux, Annie; Schiller, Nancy A.; Herreid, Ky F.; Wright, Carolyn

    2016-01-01

    This column provides original articles on innovations in case study teaching, assessment of the method, as well as case studies with teaching notes. In this month's issue the authors provide a more definitive answer to the "What Makes a Good Case?" question based on a just-completed Survey Monkey survey given to NCCSTS teachers.

  5. Volcanic emissions from soils at the base of La Fossa volcano, Vulcano island, Italy

    Science.gov (United States)

    Obenholzner, J. H.; Parks, J. L.

    2006-12-01

    A top-sealed plastic tube with a diameter of ca. 15 cm had been buried vertically at the base of La Fossa volcano, Volcano island, Italy, next to the front of the obsidian flow. The tube had been filled with quartz wool to condense vapors emanating from the soil. At ca. 75 cm below the surface the sample had been exposed to vapors from Sept. 2005 to April 2006. The leached sample had not been in touch with the ground. Another glass wool cushion (ca. 3 cm thick) had been underneath to minimize capillary effects. Leaching of the quartz wool and ICP-MS analysis documented positive values for: Mg, Al, Si, P, K, Ca, Cr, Mn, Ni, Cu, Zn, Cd, Sn, Pb. Leaching with nitric acid documented also V and Fe. Acid leaching produced higher values for all elements, except K and Sn, than leaching with deionized water. Negative values had been obtained for As, Se, Mo. Influence from soil breathing can be excluded as the active fumaroles contain As and Se. This experiment documents for the first time an unknown element transport by vapors/gases through a volcanic edifice interacting with hydrothermal and magmatic gases. It remains unknown if elements detected are entering the atmosphere or are getting adsorbed onto the volcanic ash soil particles derived from reworked surge beds. This question is very important as soils might be an unknown filter medium to filter volcanically polluted air in case of major volcanic crises. Data can be obtained from the authors.

  6. Portal cholangiopathy: case report

    Directory of Open Access Journals (Sweden)

    Maria Cecilia Almeida Maia

    2014-01-01

    Full Text Available The present report describes the case of a child that after blunt abdominal trauma presented with portal thrombosis followed by progressive splenomegaly and jaundice. Ultrasonography and percutaneous cholangiography revealed biliary dilatation secondary to choledochal stenosis caused by dilated peribiliary veins, characterizing a case of portal biliopathy. The present case report is aimed at presenting an uncommon cause of this condition.

  7. New guidelines for case reports

    Directory of Open Access Journals (Sweden)

    Mario Delgado-Noguera

    2013-09-01

    Full Text Available The case report or case reports are a frequent type of narrative article in the biomedical literature. Case reports are useful to describe unusual clinical cases, identify adverse effects or benefits of therapies. They are also useful for the description of presentation of rare diseases for educational or scientific purposes. Several groups have worked on reporting guidelines for other designs such as the case of clinical trials (CONSORT Statement or observational studies (STROBE Statement and this journal has been adopted as the guide for authors. Recently, there were presented the Guidelines for writing CAseREports (CARE Statement. The aim of this article is to make them known and comment.

  8. Casing drilling

    Energy Technology Data Exchange (ETDEWEB)

    Heenan, D. [Tesco Corp., Calgary, AB (Canada)

    2003-07-01

    This paper reviewed the experience that Tesco has gained by drilling several wells using only casings as the drill stem. Tesco has manufactured a mobile and compact hydraulic drilling rig called the Casing Drilling {sup TM} system. The system could be very effective and efficient for exploration and development of coalbed methane (CBM) reserves which typically require extensive coring. Continuous coring while drilling ahead, along wire line retrieval, can offer time savings and quick core recovery of large diameter core which is typically required for exploration core desorption tests. The proposed system may also have the potential to core or drill typically tight gas sands or underbalanced wells with air or foam. This would reduce drilling fluid damage while simultaneously finding gas. Compared to conventional drill pipes, Casing Drilling {sup TM} could also be effective with water production from shallow sands because of the smaller annual clearance which requires less air volumes to lift any produced water. 9 figs.

  9. The Legal Case

    NARCIS (Netherlands)

    Sartor, Giovanni; Contissa, Giuseppe; Schebesta, H.; Laukyte, Migle; Lanzi, Paola; Marti, Patrizia; Paola, Tomasello

    2013-01-01

    This paper presents the first release of the Legal Case, recently developed by the ALIAS Project and still under refinement. The Legal Case is a methodological tool intended to address liability issues of automated ATM systems: it provides for a legal risk management process that can be applied

  10. Tuberculosis case-finding in Cambodia: analysis of case notification data, 2000 to 2013

    Science.gov (United States)

    Furphy, Valérie Burrus; Kobayashi, Miwako; Nishikiori, Nobuyuki; Eang, Mao Tan; Yadav, Rajendra-Prasad

    2015-01-01

    The routine tuberculosis (TB) surveillance system in Cambodia has been strengthened under the National TB Programme (NTP). This paper provides an overview of the TB surveillance data for Cambodia at the national level for the period 2000 to 2013 and at the subnational level for 2013. The proportion of the total population that were screened for TB rose from 0.4% in 2001 to 1.1% in 2013, while the smear-positivity rate decreased from 28.9% to 8.1% in the same period. The total number of notified TB cases increased steadily from 2000; this has stabilized in recent years with 39 055 cases notified in 2013. The proportion of all TB cases that were smear-positive decreased from 78% in 2000 to 36% in 2013. Case notification rates (CNRs) for all forms of TB and new smear-positive TB in 2013 were 261 and 94 per 100 000 population, respectively. Higher CNRs were found in the north-western and south-eastern parts of the country and were higher for males especially in older age groups. The increase in TB screening, decline in the smear-positive rate and decline in notified smear-positive TB cases likely reflect a long-term positive impact of the NTP. A negative correlation between the proportion of the population screened and the smear-positivity rate at the subnational level helped identify where to find undiagnosed cases. Subnational differences in case notification of the elderly and in children provide more specific targets for case-finding and further encourage strategic resource allocation. PMID:25960919

  11. Reported cases of selected diseases.

    Science.gov (United States)

    1994-06-01

    The number of reported cases of measles, poliomyelitis, tetanus, diphtheria, and whooping cough for the period of January 1, 1994 to the date of the last report is presented in tabular form by country with a comparison for the same epidemiological period in 1993. The countries included are Bolivia, Colombia, Ecuador, Peru, Venezuela, Argentina, Chile, Paraguay, Uruguay, Brazil, Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, Panama, Mexico, Cuba, Haiti, the Dominican Republic, Antigua and Barbuda, the Bahamas, Barbados, Dominica, Grenada, Guyana, Jamaica, Saint Kitts and Nevis, Saint Vincent, Saint Lucia, Suriname, Trinidad and Tobago, Canada, and the US. The figures for measles are given as reported and as confirmed. In some countries, the reported number of cases of measles decreased from 1993 figures (Venezuela 5275 vs. 6060, Paraguay 26 vs. 958, Brazil 272 vs. 958, Canada 30 vs. 38), but, in others, the figure increased from 1993 (Mexico 47 vs. 21, the US 155 vs. 86). There were no reported cases of poliomyelitis for either year in any country. The figures for tetanus are divided into nonneonatal and neonatal. In Brazil the number of nonneonatal cases decreased to 360 from 371 in 1993, and the number of neonatal cases decreased to 28 from 65. In Mexico, nonneonatal cases decreased to 28 from 45, but neonatal cases increased to 23 from 20 in 1993. The number of cases of diphtheria cases in Brazil decreased to 28 from 65 in the same period of 1993. The number of cases of whooping cough decreased to 431 from 1651 in Brazil and to 51 from 70 in Mexico. However, the number of cases in Canada increased to 1047 from 784.

  12. Case Report

    DEFF Research Database (Denmark)

    Bilgin-Freiert, Arzu; Fugleholm, Kåre; Poulsgaard, Lars

    2015-01-01

    We report a case of an intraneural ganglion cyst of the hypoglossal canal. The patient presented with unilateral hypoglossal nerve palsy, and magnetic resonance imaging showed a small lesion in the hypoglossal canal with no contrast enhancement and high signal on T2-weighted imaging. The lesion...... irradiation as an option. This case illustrates a very rare location of an intraneural ganglion cyst in the hypoglossal nerve. To our knowledge there are no previous reports of an intraneural ganglion cyst confined to the hypoglossal canal....

  13. Case Study: A Step-by-Step Guide to Students Writing Case Studies (and Tools for Novice Case Authors)

    Science.gov (United States)

    Prud'homme-Genereux, Annie

    2015-01-01

    In experimenting with ways of structuring the assignment and providing guidance to students, the author developed a series of tools that may be of interest to instructors wishing to implement a case-writing assignment in their course. This assignment is more suited for instructors experienced in case writing, as their knowledge of how to design a…

  14. Case frames as contextual mappings to case law in BestPortal

    NARCIS (Netherlands)

    Hoekstra, R.; Lodder, A.; van Harmelen, F.

    2010-01-01

    This paper introduces case frames as a way to provide a more meaningful structure to vocabulary mappings used to bridge the gap between laymen and legal descriptions of court proceedings. Case frames both reduce the ambiguity of queries, and improve the ability of users to formulate good quality

  15. Patterned genital injury in cases of rape - A case-control study

    DEFF Research Database (Denmark)

    Astrup, Birgitte Schmidt; Ravn, Pernille; Thomsen, Jørgen Lange

    2013-01-01

    A pattern of genital injury that separates trauma seen in sexual assault cases from trauma seen following consensual sexual intercourse has been a matter of debate. This study aimed at clarifying the question by eliminating as many confounders as possible in a prospective, case-control setup. A t...

  16. Case management after long-term absence from work in China: a case report.

    Science.gov (United States)

    Tang, Dan; Yu, Ignatius Tak Sun; Luo, Xiaoyuan; Liang, Youxin; He, Yonghua

    2011-03-01

    Return-to-work (RTW) after occupational injuries is an important and challenging issue. Case managers are expected to play a vital role in successful RTW. In China, RTW intervention is in its early phase and requires further research and practice. This case report describes Mr. H's RTW process for illustrating the work of a case management team in China. Suggestions on developing and optimizing the process in China are given. After 9 years of absence from work due to severe burn injuries at work, Mr. H was referred for RTW interventions. Mr. H received social and occupational rehabilitation services of 3 months, and the following workplace visits and work trials. After the job placement, the case manager continued the liaison with the worker and employer. Mr. H showed positive changes in occupational and social adjustment after the case management interventions. This was reflected from the shift from the contemplation to action stage on the Lam Assessment of Stages of Employment Readiness. Despite he did not show significant changes on functional capacity and fear avoidance beliefs, Mr. H passed the job credential test and was offered a maintenance technician position at a new company. Both the worker and the employer were satisfied with the outcome of the case management. The RTW interventions carried out by the case managers appeared to be effective within the Chinese system. The results suggested that professional training of case managers, RTW-related policies and technological standards, early integrated interventions should be further developed in China. Disability Adjustment Group Therapy and RTW Support Groups perhaps are useful approaches in workers' returning to work.

  17. Measles cases among adolescents in southern Pakistan 2012-2015: The case for revisiting vaccination strategies.

    Science.gov (United States)

    Shakoor, Sadia; Khan, Erum; Rajput, Muhammad Imran; Rahimoon, Wali Muhammad

    2017-07-03

    Surveillance of adult measles in Pakistan is a challenge as it does not enjoy the status of a reportable disease unlike childhood cases and therefore cases remain undetected and unreported or misdiagnosed. Consequently no data or estimates of young adult cases, seroprevalence, or estimates of susceptible preadolescent or young adult population exist. We have presented both laboratory conformed and clinically suspected cases of measles occurring in adolescents and adults in the southern province of Sindh in Pakistan. Through an examination of 2 independent databases, i.e. a laboratory database of measles IgM positive cases and clinically detected cases on surveillance performed by the Disease Early Warning System, we have analyzed and reported age-specific positivity rates from 2012 to 2015 in Sindh, Pakistan. High rates of laboratory confirmed measles were observed in those aged 9 y and younger. Among adolescents and adults, significantly higher positivity rates were observed among those aged 10-19 y. Clinically detected cases from Sindh showed similar distribution of cases. High burden of cases among children <9 y of age confirm that supplementary immunization activities (SIAs) among this age group are inadequate and need to be strengthened. Cases among those 10-19 y further demonstrate the need for consolidating SIAs with an additional strategy to vaccinate those who remain non-immune at college entry and in institutions where outbreaks can be prevented. Such measures are essential to achieving the goal of measles elimination in the country and region.

  18. Casing Out Evaluation: Expanding Student Interest in Program Evaluation through Case Competitions.

    Science.gov (United States)

    Obrecht, Michael; Porteous, Nancy; Haddock, Blair

    1998-01-01

    Describes the authors' experiences in organizing bilingual evaluation case competitions for the National Capital Chapter of the Canadian Evaluation Society for three years. Competition structure, eligibility, judging, contestant recruiting, and preparing cases are outlined. (SLD)

  19. CLINICAL AND CEPHALOMETRIC ANALYSIS OF THREE CASES WITH PYCNODYSOSTOSIS: CASE REPORTS*

    Directory of Open Access Journals (Sweden)

    Eser ÇAPAN

    2015-01-01

    Full Text Available The aim of this article is to present intra- and extra-oral and cephalometric findings of three patients with a rare disease: the pycnodysostosis. Two cases had skeletal Class III malocclusion due to maxillary retrognathia and one had bimaxillary retrusion with Class I relationship. Total circular crossbite, increased gonial angle and vertical facial proportions, deep-narrow palates and retruded upper lip were found in all cases. Maxillary expansion, face mask treatment or/and orthognathic surgery are treatment alternatives, considering the growth and development. Bone fragility and the risk of osteomyelitis after extractions should be considered in such cases before orthodontic treatment and orthognatic surgery.

  20. Safety case plan 2008

    International Nuclear Information System (INIS)

    2008-07-01

    Following the guidelines set forth by the Ministry of Trade and Industry (now Ministry of Employment and Economy) Posiva is preparing to submit the construction license application for a spent fuel repository by the end of the year 2012. The long-term safety section supporting the license application is based on a safety case, which, according to the internationally adopted definition, is a compilation of the evidence, analyses and arguments that quantify and substantiate the safety and the level of expert confidence in the safety of the planned repository. In 2005, Posiva presented a plan to prepare such a safety case. The present report provides a revised plan of the safety case contents mentioned above. The update of the safety case plan takes into account the recommendations made by the Radiation and Nuclear Safety Authority (STUK) about improving the focus and further developing the plan. Accordingly, particular attention is given to the quality management of the safety case work, the management of uncertainties and the scenario methodology. The quality management is based on the ISO 9001:2000 standard process thinking enhanced with special features arising from STUK's YVL Guides. The safety case production process is divided into four main sub-processes. The conceptualisation and methodology sub-process defines the framework for the assessment. The critical data handling and modelling sub-process links Posiva's main technical and scientific activities to the production of the safety case. The assessment sub-process analyses the consequences of the evolution of the disposal system in various scenarios, classified either as part of the expected evolution or as disruptive scenarios. The compliance and confidence sub-process is responsible for final evaluation of compliance of the assessment results with the regulatory criteria and the overall confidence in the safety case. As in the previous safety case plan, the safety case will be based on several reports, but

  1. A clear case. Selective investment in case management applications can yield significant returns.

    Science.gov (United States)

    Hagland, Mark

    2009-03-01

    Strategically conceived case management system implementation makes good patient care and business sense, CIOs agree. Significant financial savings can be achieved from case management IS implementations, if those implementations are executed in the context of partnership between clinical leaders and the CIO's team. CIOs agree that applying the concept of "investment" to the implementation of case management IT can make resource allocation decisions easier.

  2. 'Case reporting of rare adverse events in otolaryngology': can we defend the case report?

    LENUS (Irish Health Repository)

    Dias, Andrew

    2012-01-31

    The study of errors in medicine has proliferated since the publication of The Institute of Medicine Report \\'TO ERR IS HUMAN\\' in 2000. Case nuances and process of care issues are valuable areas to explore if the goal is to provide the health care worker with the knowledge to avoid future errors. Meta-analysis and randomized controlled trials provide a large data base of evidence towards improvement and opportunities, but it is suggested that case reports can still provide valuable clinical information. The aim is to use the published literature to produce a series of rare harm case reports in E.N.T. The methods include systematic literature review. Journals searched in PUBMED were 60. Rare harm case obtained from the search were 5,322. Rare harm case reports not reported in any other form of evidence-based medicine were 40. Yes, the case report can be defended as it is an important pillar of evidence-based medicine.

  3. SARS: a comparative study on the chest radiography of the mortal cases and the cured cases

    International Nuclear Information System (INIS)

    Jiang Songfeng; Liu Jingxin; Chen Bihua; Zhang Lieguang; Yin Chibiao; Zhang Fuchun

    2003-01-01

    Objective: This study is mainly on the radiological findings of the mortal cases of SARS. Methods: The chest X-ray (CXR) findings of 11 mortal cases of SARS were retrospectively studied, and compared with those of the 249 cured cases. Results: The major CXR findings of the mortal cases were: patchy shadows in 10 cases out of 11 (90.90%), frosted glass like change of the lung fields in 9 (81.82%), diffuse lesions in 11 (100%), and involvement of the bilateral lung. There was a statistical difference between the mortal cases and the cured cases on the following 4 manifestations: large shadows, extensive consolidation, frosted glass like change of the lung fields, and diffuse lesions (P<0.01). Conclusion: Large shadows, extensive consolidation, frosted glass like change of the lung fields, diffuse lesions and the bilateral involvement of the lung are the main CXR findings of the mortal cases of SARS. And extensive consolidation and diffuse involvement are strongly indicative. In most of the mortal cases, the latest CXR demonstrated widespread frosted glass like appearance in the lung fields with air bronchogram

  4. Non-ferromagnetic overburden casing

    Science.gov (United States)

    Vinegar, Harold J.; Harris, Christopher Kelvin; Mason, Stanley Leroy

    2010-09-14

    Systems, methods, and heaters for treating a subsurface formation are described herein. At least one system for electrically insulating an overburden portion of a heater wellbore is described. The system may include a heater wellbore located in a subsurface formation and an electrically insulating casing located in the overburden portion of the heater wellbore. The casing may include at least one non-ferromagnetic material such that ferromagnetic effects are inhibited in the casing.

  5. "Since I have my case manager, I am back to life" case management in Croatia.

    Science.gov (United States)

    Gruber, Ema N; Ivezić-Strkalj, Sladana; Agius, Mark; Martić-Biocina, Sanja

    2008-03-01

    The authors present a case report of a patient who was treated by a case manager, a member of a Croatian Community Mental Health (CMH) Team, following the recommendations of WHO 2004 as well as the IRIS guidelines and the Basic Standards for Management of Patients with Serious Mental Illness in the Community (Agius 2005) and using the elements of Clinical case management (Muser 1998), Assertive community treatment model (Burns 1995, Scott 1995, Wolfsan 1990), the personal strength model (Rapp 1988) and Rehabilitation model (Anthony 1993). In order to emphasize the importance of the therapist-patient relationship in the treatment of chronic schizophrenic patients (Ivezic 2001) and creating the group atmosphere a Croatian model of case management is created where the patient's needs and risks are assessed by a multidisciplinary team which also conducts the recommended psychosocial interventions plan. The majority of interventions are conducted in groups. The case manager develops a confident relationship with a patient, nourishes the positive transference and aids the delivery of the treatment. The main goals of the interventions are empowerment of the patient, improvement of his abilities and decreasing of disabilities. The case manager also carries out a full assessment of the needs of the patient's family so that the family or carers are also included in the treatment or support if necessary (Gruber 2006). A case report of a patient and the work of her case manager as well as the case manager's diary (Gruber 2007) and the Croatian model of case management is presented in this article.

  6. Nurse Case Managers' Experiences on Case Management for Long-term Hospitalization in Korea

    OpenAIRE

    Jinjoo Oh, Ph.D., RN, GNP; Seieun Oh, Ph.D., RN

    2017-01-01

    Purpose: The implementation of case management for long-term hospitalization use has been approved for controlling medical cost increases in other countries. But, introduction of the case management in Korea has created issues that hinder its effective operation. This qualitative study aimed to obtain further understanding of the issues surrounding the management of Medical Aid beneficiaries' use of long-term hospitalization from the case managers' perspectives and to provide suggestions for ...

  7. Timeliness of Operating Room Case Planning and Time Utilization: Influence of First and To-Follow Cases

    Directory of Open Access Journals (Sweden)

    Konrad Meissner

    2017-04-01

    Full Text Available Resource and cost constraints in hospitals demand thorough planning of operating room schedules. Ideally, exact start times and durations are known in advance for each case. However, aside from the first case’s start, most factors are hard to predict. While the role of the start of the first case for optimal room utilization has been shown before, data for to-follow cases are lacking. The present study therefore aimed to analyze all elective surgery cases of a university hospital within 1 year in search of visible patterns. A total of 14,014 cases scheduled on 254 regular working days at a university hospital between September 2015 and August 2016 underwent screening. After eliminating 112 emergencies during regular working hours, 13,547 elective daytime cases were analyzed, out of which 4,346 ranked first, 3,723 second, and 5,478 third or higher in the daily schedule. Also, 36% of cases changed start times from the day before to 7:00 a.m., with half of these (52% resulting in a delay of more than 15 min. After 7:00 a.m., 87% of cases started more than 10 min off schedule, with 26% being early and 74% late. Timeliness was 15 ± 72 min (mean ± SD for first, 21 ± 84 min for second, and 25 ± 93 min for all to-follow cases, compared to preoperative day planning, and 21 ± 45, 23 ± 61, and 19 ± 74 min compared to 7:00 a.m. status. Start time deviations were also related to procedure duration, with cases of 61–90 min duration being most reliable (deviation 9.8 ± 67 min compared to 7:00 a.m., regardless of order. In consequence, cases following after 61–90 min long cases had the shortest deviations of incision time from schedule (16 ± 66 min. Taken together, start times for elective surgery cases deviate substantially from schedule, with first and second cases falling into the highest mean deviation category. Second cases had the largest deviations from scheduled times compared to

  8. Pressurized waterproof case electronic device

    KAUST Repository

    Berumen, Michael L.

    2013-01-31

    A pressurized waterproof case for an electronic device is particularly adapted for fluid-tight containment and operation of a touch-screen electronic device or the like therein at some appreciable water depth. In one example, the case may be formed as an enclosure having an open top panel or face covered by a flexible, transparent membrane or the like for the operation of the touchscreen device within the case. A pressurizing system is provided for the case to pressurize the case and the electronic device therein to slightly greater than ambient in order to prevent the external water pressure from bearing against the transparent membrane and pressing it against the touch screen, thereby precluding operation of the touch screen device within the case. The pressurizing system may include a small gas cartridge or may be provided from an external source.

  9. An unusual case of neonatal mastocytoma: A case report

    Directory of Open Access Journals (Sweden)

    Guglielmo Pranteda

    2017-08-01

    Full Text Available Mastocytosis is a group of disorders characterized by the accumulation of mast cells in various tissues. In this article we report an interesting case of cutaneous mastocytoma in a 3-month-old infant. We describe two episodes characterized by an exacerbation of the skin lesion with the typical Darier’s sign. Both of them occurred after breastfeeding. In both episodes, the mother had eaten shrimps before the breastfeeding. This peculiar case, difficult to understand regarding its pathogenesis, was successful resolved just with dietary prescription given to the breast feeding mother.

  10. Making a case for case studies in psychotherapy training

    DEFF Research Database (Denmark)

    Mackrill, Thomas Edward; Iwakabe, Shigeru

    2013-01-01

    articulated explicitly or researched systematically in spite of its cardinal importance. An analysis of the role of case studies in psychotherapy training is presented. Reading, watching, or hearing about cases can offer novice psychotherapists access to a closed world; access to psychological theory...... in action; access to whole courses of therapy; access to different approaches; access to significant moments; access to the therapeutic relationship; access to a wide range of client types; access to working in different contexts; and the opportunity of identifying with therapists and clients. Writing...

  11. Case Report: A Unique Case Of Cystic Echinococcosis in a Sahiwal ...

    African Journals Online (AJOL)

    Case Report: A Unique Case Of Cystic Echinococcosis in a Sahiwal Cow in Narok County, Kenya. JA Omega, PK Koskei. Abstract. A three and a half year old pregnant Sahiwal cow born and reared just outside the Maasai Mara National Game Reserve in Narok County, Kenya was noticed to walk slowly, cough occasionally ...

  12. [Rectal duplication cyst--case report].

    Science.gov (United States)

    Turyna, R; Horák, L; Kucera, E; Hejda, V; Krofta, L; Feyereisl, J

    2009-06-01

    The authors demonstrate a rare case of duplication anomaly of the rectum. Case report. Institute for the Care of Mother and Child, Prague. We present a rare case of cystic rectal duplication in adult, completely removed and histologically confirmed. A literature review was summarized. The case was complicated by delay in diagnosis, multiple operations, and by the association with endometriosis, as well. Mentioned anomaly is published in the Czech literature for the very first time.

  13. Differences in the clinical-epidemiological profile between new cases of tuberculosis and retreatment cases after default

    Directory of Open Access Journals (Sweden)

    Aylana de Souza Belchior

    Full Text Available Abstract OBJECTIVE To identify the socioeconomic and clinical-epidemiological factors related to tuberculosis in new cases and retreatment cases. METHOD Comparative study with 126 patients, of which 42 were retreatment cases after default attended in a reference center, and 84 were new cases completing the first treatment and treated in Basic Health Units. The collection of primary data was through interview, and of secondary data by records of the Notifiable Diseases Information System. Comparative analysis between the two groups. RESULTS The new cases differ from retreatment cases regarding educational level. The clinical-epidemiological profile shows a significant difference in relation to performance of the tuberculin skin test, and the HIV test result (positive in favor of new cases. In relation to performance of sputum culture and the result (positive of the first sputum smear of the first and second samples, in favor of retreatment cases. CONCLUSION The two groups are significantly different in clinical and epidemiological characteristics that show the access to exams.

  14. Preliminary energy demand studies for Ireland: base case and high case for 1980, 1985 and 1990

    Energy Technology Data Exchange (ETDEWEB)

    Henry, E W

    1981-01-01

    The framework of the Base Case and the High Case for 1990 for Ireland, related to the demand modules of the medium-term European Communities (EC) Energy Model, is described. The modules are: Multi-national Macre-economic Module (EURECA); National Input-Output Model (EXPLOR); and National Energy Demand Model (EDM). The final results of the EXPLOR and EDM are described; one set related to the Base Case and the other related to the High Case. The forecast or projection is termed Base Case because oil prices are assumed to increase with general price inflation, at the same rate. The other forecast is termed High Case because oil prices are assumed to increase at 5% per year more rapidly than general price inflation. The EXPLOR-EDM methodology is described. The lack of data on energy price elasticities for Ireland is noted. A comparison of the Base Case with the High Case is made. (MCW)

  15. Case Managers on the Front Lines of Ethical Dilemmas: Advocacy, Autonomy, and Preventing Case Manager Burnout.

    Science.gov (United States)

    Sortedahl, Charlotte; Mottern, Nina; Campagna, Vivian

    The purpose of this article is to examine how case managers are routinely confronted by ethical dilemmas within a fragmented health care system and given the reality of financial pressures that influence life-changing decisions. The Code of Professional Conduct for Case Managers (Code), published by the Commission for Case Manager Certification, acknowledges "case managers may often confront ethical dilemmas" (Code 1996, Rev. 2015). The Code and expectations that professional case managers, particularly those who are board certified, will uphold ethical and legal practice apply to case managers in every practice setting across the full continuum of health care. This discussion acknowledges the ethical dilemmas that case managers routinely confront, which empowers them to seek support, guidance, and resources to support ethical practice. In addition, the article seeks to raise awareness of the effects of burnout and moral distress on case managers and others with whom they work closely on interdisciplinary teams.

  16. Describing Case Study Method and Identifying the Factors that Contribute to the Successful Conduct of Case Studies

    OpenAIRE

    Ahmad H. Juma'h; Mustafa Cavus

    2001-01-01

    This article has attempted to describe case study, the limitations and critiques on case study methodology and how the proponents have responded to these. Our special focus have been on the debate on theory building from case study research, and a framework for conducting case study research as well as the factors for a successful case study research. The overall conclusion is that the case study has been inappropriately used to generate theories.

  17. Cheilitis granulomatosa: Case series

    Directory of Open Access Journals (Sweden)

    Sudha Rani Chintagunta

    2017-01-01

    Full Text Available Granulomatous cheilitis is an idiopathic inflammatory disorder characterized by persistent, asymptomatic, diffuse swelling of one or both lips. It is also considered as an oligosymptomatic or monosymptomatic form of Melkersson–Rosenthal syndrome. We herewith report five cases of granulomatous cheilitis of which three cases were females and two were males. The mean age was 41 years. The average duration of symptoms was 2.5 years (2–3 years. Four patients presented with asymptomatic persistent swelling of the upper lip and one patient with lower lip. Two cases showed associated fissuring and angular cheilitis. One case also showed involvement of the left cheek. All the patients showed moderate improvement with combination of minocycline and intralesional triamcinolone therapy.

  18. Measles (Rubeola) Cases and Outbreaks

    Science.gov (United States)

    ... Address What’s this? Submit What's this? Submit Button Measles Cases and Outbreaks Language: English (US) Español (Spanish) ... Español: Casos y brotes de sarampión Number of measles cases by year since 2010 Measles cases per ...

  19. Case-control studies in neurosurgery.

    Science.gov (United States)

    Nesvick, Cody L; Thompson, Clinton J; Boop, Frederick A; Klimo, Paul

    2014-08-01

    Observational studies, such as cohort and case-control studies, are valuable instruments in evidence-based medicine. Case-control studies, in particular, are becoming increasingly popular in the neurosurgical literature due to their low cost and relative ease of execution; however, no one has yet systematically assessed these types of studies for quality in methodology and reporting. The authors performed a literature search using PubMed/MEDLINE to identify all studies that explicitly identified themselves as "case-control" and were published in the JNS Publishing Group journals (Journal of Neurosurgery, Journal of Neurosurgery: Pediatrics, Journal of Neurosurgery: Spine, and Neurosurgical Focus) or Neurosurgery. Each paper was evaluated for 22 descriptive variables and then categorized as having either met or missed the basic definition of a case-control study. All studies that evaluated risk factors for a well-defined outcome were considered true case-control studies. The authors sought to identify key features or phrases that were or were not predictive of a true case-control study. Those papers that satisfied the definition were further evaluated using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) checklist. The search detected 67 papers that met the inclusion criteria, of which 32 (48%) represented true case-control studies. The frequency of true case-control studies has not changed with time. Use of odds ratios (ORs) and logistic regression (LR) analysis were strong positive predictors of true case-control studies (for odds ratios, OR 15.33 and 95% CI 4.52-51.97; for logistic regression analysis, OR 8.77 and 95% CI 2.69-28.56). Conversely, negative predictors included focus on a procedure/intervention (OR 0.35, 95% CI 0.13-0.998) and use of the word "outcome" in the Results section (OR 0.23, 95% CI 0.082-0.65). After exclusion of nested case-control studies, the negative correlation between focus on a procedure

  20. Case-control studies in diabetes. Do they really use a case-control design?

    Science.gov (United States)

    Ramos, Analía; Mendoza, Lilian Cristina; Rabasa, Fernanda; Bolíbar, Ignasi; Puig, Teresa; Corcoy, Rosa

    2017-07-01

    Studies defined as case-control do not always use this design. We aimed to estimate the frequency of mislabelled case-control studies in published articles in the area of diabetes and to identify the predictors of incorrect labelling. We searched Medline and Web of Science for articles with "diabetes" and "case control" in title and filtered for language (English/Romance) and period (January 2010-December 2014). Inclusion criteria were: (1) statement to use a case-control design in title, (2) to be a final full-length publication and (3) to have original data in the area of diabetes. Three independent reviewers went through titles, looked for full texts and reviewed them. Discrepancies were settled with a fourth reviewer. Expert epidemiologist advice was requested in case of doubt. case-control mislabelling; addressed predictors: publication year, journal impact factor and journal subject. proportion of mislabelled CC articles and assessment of predictors by multivariate logistic regression analysis. We retrieved 362 articles, 251 of them fulfilling inclusion criteria. The proportion of mislabelled CC studies was 43.8% (confidence interval 95% 37.7-50.0%). Most mislabelled studies had a cross-sectional design (82.7%). Predictors of mislabelling were publication year, journal impact factor and journal area. A relevant subset of studies defined as case-control in the area of diabetes correspond to mislabelled cross-sectional studies. Incorrect labelling misleads readers regarding the interpretation of results and the cause-effect hypothesis. Researchers, reviewers and editors should be aware of and commit to settle this issue.

  1. Case Reports, Case Series - From Clinical Practice to Evidence-Based Medicine in Graduate Medical Education.

    Science.gov (United States)

    Sayre, Jerry W; Toklu, Hale Z; Ye, Fan; Mazza, Joseph; Yale, Steven

    2017-08-07

    Case reports and case series or case study research are descriptive studies that are prepared for illustrating novel, unusual, or atypical features identified in patients in medical practice, and they potentially generate new research questions. They are empirical inquiries or investigations of a patient or a group of patients in a natural, real-world clinical setting. Case study research is a method that focuses on the contextual analysis of a number of events or conditions and their relationships. There is disagreement among physicians on the value of case studies in the medical literature, particularly for educators focused on teaching evidence-based medicine (EBM) for student learners in graduate medical education. Despite their limitations, case study research is a beneficial tool and learning experience in graduate medical education and among novice researchers. The preparation and presentation of case studies can help students and graduate medical education programs evaluate and apply the six American College of Graduate Medical Education (ACGME) competencies in the areas of medical knowledge, patient care, practice-based learning, professionalism, systems-based practice, and communication. A goal in graduate medical education should be to assist residents to expand their critical thinking, problem-solving, and decision-making skills. These attributes are required in the teaching and practice of EBM. In this aspect, case studies provide a platform for developing clinical skills and problem-based learning methods. Hence, graduate medical education programs should encourage, assist, and support residents in the publication of clinical case studies; and clinical teachers should encourage graduate students to publish case reports during their graduate medical education.

  2. Three cases of pulmonary varix

    Energy Technology Data Exchange (ETDEWEB)

    Takishima, Teruo; Sakuma, Hajime; Tajima, Tsunemi; Okimoto, Takao; Yamamoto, Keiichiro; Dohi, Yutaka (Saitama Medical School (Japan))

    1982-06-01

    Three cases of pulmonary varix associated with valvular heart disease were reported. Round shadows were clearer on first oblique or lateral films of chest x-ray in all 3 cases. On chest tomograms, the shadows were substantial and round-elliptical. RI angiography with sup(99m)Tc-RBC demonstrated these shadows in agreement with the site of influx of the pulmonary vein into the left atrium in Cases 1 and 3 and with the pulmonary vein slightly apart from the left atrium in Case 2. On CT scans in Cases 1 and 3, enhancement with a contrast medium visualized dilatation of the pulmonary vein close to, and in continuation with, the shadow of the left atrium. The diagnosis of pulmonary varix in agreement with the venous phase of pulmonary angiography was made for all 3 cases. Non-surgical examinations (especially CT scan) proved highly useful for the diagnosis of pulmonary varix.

  3. Five Misunderstandings About Case-Study Research

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent

    2006-01-01

    This article examines five common misunderstandings about case-study research: (a) theoretical knowledge is more valuable than practical knowledge; (b) one cannot generalize from a single case, therefore, the single-case study cannot contribute to scientific development; (c) the case study is most...... useful for generating hypotheses, whereas other methods are more suitable for hypotheses testing and theory building; (d) the case study contains a bias toward verification; and (e) it is often difficult to summarize specific case studies. This article explains and corrects these misunderstandings one...

  4. Retrospective evaluation of childhood alopecia areata cases

    Directory of Open Access Journals (Sweden)

    Munise Daye

    2013-09-01

    Full Text Available Background and design: Approximately 20% of alopecia areata (AA cases are children. There is limited information about childhood AA.We aimed to examine demographic features,treatments and diseases prognosis of child cases of AA that were followed in our clinic. Material and methods: Datas of 110 AA patients who are 16 and under 16 years old were examined retrospectively.The age,gender,disease onset age,duration of disease,types of AA and onset area,nail involvement, accompanying systemic and dermatological diseases,laboratory tests,treatments and the prognosis were evaluated in their follow-up time.Results: Female cases were 46,4%, male cases were 53,6%.The mean age was 10,35 years.The age of disease onset was 8,65 years.Primary onset areas of AA cases were scalp in 83,6%, eyebrows in 5,4%, body hair in 5,4%, eyelashes in 2,7%, eyebrows and eyelashes in 2,7%.Types of disease were AA in 73,4% cases,alopecia totalis in 19% cases, alopecia universalis in 5,4% cases,ophiaisis in 1,8% cases.Nail involvement was established in 36,3% cases. Nevus flammeus was established in 2,7% cases.Mean disease duration was 17,02 months.Accompaying dermatosis were vitiligo in 2,7% cases,atopic dermatitis in 6,3% cases. The accompaying systemic diseases were autoimmune thyroiditis in 1,8% cases and Down's Syndrome in 2,7% cases.Thyroid autoantibodies were high in 0,9% cases.We have treated 24,5% of cases with topical corticosteroid lotion, 30,9% of cases with anthralin, 0,9%of cases with 2% minoxidil lotion, 0,9% of cases with calcipotriol lotion, 1,8% of cases with topical calcineurin inhibitors, 10% of cases with intralesional corticosteroids.We have treated 15,4% of cases with systemic corticosteroids and PUVA therapy who were resistant to topical treatment.We have treated 14,5% of cases with different combinations of topical treatments.Remission was observed in 34,5% of cases.The mean remission duration was 12.2 months.Relapse was observed at a average of two

  5. Case Study: Mini-Case Studies: Small Infusions of Active Learning for Large-Lecture Courses

    Science.gov (United States)

    Carloye, Lisa

    2017-01-01

    In this article, the author introduces the usage of case studies to be an excellent method for engaging students through stories. The author notes she developed a series of mini-case studies that can be implemented, with a little advance preparation, within a 10- to 15-minute window during lecture. What makes them "mini" case studies?…

  6. Case-based ethics instruction: the influence of contextual and individual factors in case content on ethical decision-making.

    Science.gov (United States)

    Bagdasarov, Zhanna; Thiel, Chase E; Johnson, James F; Connelly, Shane; Harkrider, Lauren N; Devenport, Lynn D; Mumford, Michael D

    2013-09-01

    Cases have been employed across multiple disciplines, including ethics education, as effective pedagogical tools. However, the benefit of case-based learning in the ethics domain varies across cases, suggesting that not all cases are equal in terms of pedagogical value. Indeed, case content appears to influence the extent to which cases promote learning and transfer. Consistent with this argument, the current study explored the influences of contextual and personal factors embedded in case content on ethical decision-making. Cases were manipulated to include a clear description of the social context and the goals of the characters involved. Results indicated that social context, specifically the description of an autonomy-supportive environment, facilitated execution of sense making processes and resulted in greater decision ethicality. Implications for designing optimal cases and case-based training programs are discussed.

  7. Political Psychopathy : Fujimori case

    OpenAIRE

    Nizama Valladolid, Martin

    2014-01-01

    Seven years after his political fall, Alberto Fujimori Fujimori was extradited from Chile on September 22 of 2007, in order to judge him by two cases of human rights violations and five corruption cases. The mega-trial begun on december 10 of 2007. According to the mediate authorship theory, having led the command in charge of the counterterrorist actions involves him in crimes related to human rights. The Supreme court special penal division judges him by six cases related to human rights, c...

  8. A case of unilateral dysmenorrhea

    Directory of Open Access Journals (Sweden)

    Tulon Borah

    2010-01-01

    Full Text Available Unilateral dysmenorrhea in an adolescent may be associated with uterine malformation. Relevant investigations in suspected cases and timely intervention can prevent future complications in such cases. Here, we present a case of unicornuate uterus with rudimentary horn in an adolescent complaining of unilateral dysmenorrhea.

  9. Xeroderma pigmentosum (case report

    Directory of Open Access Journals (Sweden)

    Dubey Arvind

    1990-01-01

    Full Text Available Xeroderma pigmentosum is a rare, hereditary and fatal disease of the skin. Ocular involvement is known to occur in 80% of cases. A case with typical cutaneous and ocular lesions is reported.

  10. Membranous Dysmenorrhea: A Case Series

    Science.gov (United States)

    Omar, Hatim A.; Smith, Shawn J.

    2007-01-01

    The purpose was to illustrate the variability of hormonal contraception of patients that presented with membranous dysmenorrheal. A case analysis chart review was completed on six patients referred to a Pediatric Gynecologist in an academic setting. In each case the patient underwent a thorough pelvic and bimanual exam. Following the initial presentation, each patient continued to be followed on a regular visits. Cases: Two were using the transdermal contraceptive patch and oral contraceptive, but following the expulsion of decidual cast, they were both placed on depot medroxyprogesterone acetate (DMPA) without further complications. Three of the six cases were on DMPA prior to the similar occurrence of membranous dysmenorrheal and following this incident, continued on DMPA without further problems. The final case was on the transdermal patch prior to decidual cast expulsion and remained on this form of hormonal contraception without further complications. These cases indicate that membranous dysmenorrheal is not limited to the use of DMPA. PMID:18060329

  11. Three cases of pulmonary varix

    International Nuclear Information System (INIS)

    Takishima, Teruo; Sakuma, Hajime; Tajima, Tsunemi; Okimoto, Takao; Yamamoto, Keiichiro; Dohi, Yutaka

    1982-01-01

    Three cases of pulmonary varix associated with valvular heart disease were reported. Round shadows were clearer on first oblique or lateral films of chest x-ray in all 3 cases. On chest tomograms, the shadows were substantial and round-elliptical. RI angiography with sup(99m)Tc-RBC demonstrated these shadows in agreement with the site of influx of the pulmonary vein into the left atrium in Cases 1 and 3 and with the pulmonary vein slightly apart from the left atrium in Case 2. On CT scans in Cases 1 and 3, enhancement with a contrast medium visualized dilatation of the pulmonary vein close to, and in continuation with, the shadow of the left atrium. The diagnosis of pulmonary varix in agreement with the venous phase of pulmonary angiography was made for all 3 cases. Non-surgical examinations (especially CT scan) proved highly useful for the diagnosis of pulmonary varix. (Chiba, N.)

  12. Comparing colon cancer outcomes: The impact of low hospital case volume and case-mix adjustment.

    Science.gov (United States)

    Fischer, C; Lingsma, H F; van Leersum, N; Tollenaar, R A E M; Wouters, M W; Steyerberg, E W

    2015-08-01

    When comparing performance across hospitals it is essential to consider the noise caused by low hospital case volume and to perform adequate case-mix adjustment. We aimed to quantify the role of noise and case-mix adjustment on standardized postoperative mortality and anastomotic leakage (AL) rates. We studied 13,120 patients who underwent colon cancer resection in 85 Dutch hospitals. We addressed differences between hospitals in postoperative mortality and AL, using fixed (ignoring noise) and random effects (incorporating noise) logistic regression models with general and additional, disease specific, case-mix adjustment. Adding disease specific variables improved the performance of the case-mix adjustment models for postoperative mortality (c-statistic increased from 0.77 to 0.81). The overall variation in standardized mortality ratios was similar, but some individual hospitals changed considerably. For the standardized AL rates the performance of the adjustment models was poor (c-statistic 0.59 and 0.60) and overall variation was small. Most of the observed variation between hospitals was actually noise. Noise had a larger effect on hospital performance than extended case-mix adjustment, although some individual hospital outcome rates were affected by more detailed case-mix adjustment. To compare outcomes between hospitals it is crucial to consider noise due to low hospital case volume with a random effects model. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Case law

    International Nuclear Information System (INIS)

    2012-01-01

    This section gathers the following case laws: 1 - Canada: Judicial review of Darlington new nuclear power plant project; Appeal decision upholding criminal convictions related to attempt to export nuclear-related dual-use items to Iran: Her Majesty the Queen V. Yadegari; 2 - European Commission: Greenland cases; 3 - France: Chernobyl accident - decision of dismissal of the Court of Appeal of Paris; 4 - Slovak Republic: Aarhus Convention compliance update; 5 - United States: Judgement of a US court of appeals upholding the NRC's dismissal of challenges to the renewal of the operating licence for Oyster Creek Nuclear Generating Station; reexamination of the project of high-level waste disposal site at Yucca Mountain

  14. Rare case of transverse testicular ectopia - Case report and review of literature.

    Science.gov (United States)

    Raj, Vinod; Redkar, Rajeev; Krishna, Swathi; Tewari, Shruti

    2017-01-01

    This case report has been reported in line with the SCARE criteria; Consensus-based surgical case report guidelines of International Journal of Surgery 2016. Transverse Testicular Ectopia (TTE) is a rare condition which manifests with unilateral undescended testis and contralateral hernia. Till now around 100 cases have been described in the literature. The management depends on the anatomy of the vas, vessels and testis found on surgical exploration. An algorithm exists for its management and we propose a modified algorithm for management of TTE. Five year male presented with complaints of unilateral undescended testis on the right and hernia on the left. Clinically the right testis was impalpable and left testis palpable in the left hemiscrotum and fluid hernia on the same side. Transverse testicular ectopia is a rare condition presenting with UDT and contralateral inguinal hernia. Although more than 100 cases have been described in the literature so far, those managed with a transeptal contralateral orchidopexy are two cases to the best of our knowledge. TTE was first described by Von Lenhossek in 1886. The mean age of presentation is around 4 years and most of the cases are diagnosed on surgical exploration. The management of TTE remains controversial even though an algorithm has been described for its management due to its varied presenting scenarios. TTE is a rare condition which requires high index of suspicion for diagnosis preoperatively. Whenever suspected we recommend an USG and/or MRI prior to diagnostic laparoscopy and proceed with orchidopexy. Diagnostic laparoscopy is both helpful in diagnosis and management. Transeptal contralateral orchidopexy gives good tension free fixation of testes in the scrotum.

  15. BOS MOrth cases prize 2011.

    Science.gov (United States)

    Patel, Jigar Vipinchandra

    2013-12-01

    This paper describes the orthodontic treatment of two cases awarded the prize by the British Orthodontic Society for best treated cases submitted for the Membership in Orthodontics. The first case reports on the treatment of a class III malocclusion with increased vertical lower anterior facial proportions and dentoalveolar compensation that was treated with orthodontic camouflage. The second case reports on the treatment of a class II division II malocclusion with reduced vertical lower anterior facial proportions and an overbite complete to the palate, which was treated with orthodontic camouflage.

  16. Theory Testing Using Case Studies

    DEFF Research Database (Denmark)

    Møller, Ann-Kristina Løkke; Dissing Sørensen, Pernille

    2014-01-01

    The appropriateness of case studies as a tool for theory testing is still a controversial issue, and discussions about the weaknesses of such research designs have previously taken precedence over those about its strengths. The purpose of the paper is to examine and revive the approach of theory...... testing using case studies, including the associated research goal, analysis, and generalisability. We argue that research designs for theory testing using case studies differ from theorybuilding case study research designs because different research projects serve different purposes and follow different...... research paths....

  17. A challenging case of invasive pulmonary aspergillosis after near-drowning: a case report and literature review.

    Science.gov (United States)

    Jenks, Jeffrey D; Preziosi, Michael

    2015-09-01

    Near-drowning, a relatively common event, is often complicated by subsequent pneumonia. While endogenous and exogenous bacteria are typical pathogens, rarely fungi are as well. We report a complicated case of invasive pulmonary aspergillosis in a 30-year-old man after a near-drowning event. We also review the medical literature for similar cases. All cases of invasive pulmonary aspergillosis after near-drowning reported in the literature involve Aspergillus fumigatus . The majority of cases involved submersion in stagnant water after a motor vehicle accident (MVA). Treatment varied considerably, with amphotericin B used in the majority of cases. Morbidity was considerable with prolonged hospitalization occurring in every case, and mortality occurring in fifty percent of the reported cases. Although a rare complication of near-drowning, invasive pulmonary aspergillosis can occur and lead to significant morbidity and mortality. After near-drowning A. fumigatus isolated from the respiratory tract should be assumed to be a true pathogen and treated accordingly.

  18. Some of the cases

    DEFF Research Database (Denmark)

    Eller, Nanna Hurwitz; Mogensen, Jørn Thykjær; Gyntelberg, Finn

    2014-01-01

    Some of the cases of acknowledged occupational psychiatric disorder in Denmark have been exposed to negative press coverage. Such individuals might have been exposed to violence to a lower extent than other with an acknowledged psychological work injury. We compared 25 cases with 35 controls...... matched on age and gender. The cases had experienced significantly fewer incidents of violence and had less anxiety and flashback symptoms than the controls. The results suggest that the negative press coverage was the reason for the psychiatric symptoms rather than exposures at the workplace....

  19. 451 Case studies Cardiac

    African Journals Online (AJOL)

    Marinda

    Case Studies. 29 ... A case of a 26-year-old ASA I physical status male undergoing septoplasty had an abrupt ... myocardial infarction, severe hypertensive crisis, cerebral .... or no formal management is required in an ASA I patient.8 One.

  20. Five misunderstandings about case study research

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent

    2004-01-01

    This article examines five common misunderstandings about case-study research: (1) Theoretical knowledge is more valuable than practical knowledge; (2) One cannot generalize from a single case, therefore the single case study cannot contribute to scientific development; (3) The case study is most...... useful for generating hypotheses, while other methods aremore suitable for hypotheses testing and theory building; (4) The case study contains a bias toward verification; and (5) It is often difficult to summarize specific case studies. The article explains and corrects these misunderstandings one by one...... and concludes with the Kuhnian insight that a scientific discipline without a large number of thoroughly executed case studies is a discipline without systematic production of exemplars, and that a discipline without exemplars is an ineffective one. Social science may be strengthened by the execution of more...

  1. Emotion, Engagement, and Case Studies

    Science.gov (United States)

    Herreid, Clyde Freeman; Terry, David R.; Lemons, Paula; Armstrong, Norris; Brickman, Peggy; Ribbens, Eric

    2014-01-01

    Three college faculty taught large general biology classes using case studies and personal response systems (clickers). Each instructor taught the same eight cases in two different sections, except the questions within the cases differed. In one section the questions were lower order (LO) factual inquiries, and in the other they were largely…

  2. PHAKOMATOSIS PIGMENTOVASCULARIS: REPORT OF A CASE

    Directory of Open Access Journals (Sweden)

    Mostafa Mirshams-Shahshahani

    1995-06-01

    Full Text Available The present study introduces a rare case of phakomatosispigmenJovascularis, which is charaderiud by the existence ofpigmentary naevus ond vascular naevus. Until 1985, 63 cases ofthis syndrome have been reported, mostly in Japon (56 cases. This is the first case of phakomatosis pigmentovascularis, reported in Iran.

  3. "Tuberculosis Case Management" Training.

    Science.gov (United States)

    Knebel, Elisa; Kolodner, Jennifer

    2001-01-01

    The need to isolated health providers with critical knowledge in tuberculosis (TB) case management prompted the development of "Tuberculosis Case Management" CD-ROM. Features include "Learning Center,""Examination Room," and "Library." The combination of audio, video, and graphics allows participants to…

  4. Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses.

    Science.gov (United States)

    Keogh, Ruth H; Mangtani, Punam; Rodrigues, Laura; Nguipdop Djomo, Patrick

    2016-01-05

    Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

  5. Factors associated with tuberculosis cases in Semarang District, Indonesia: case-control study performed in the area where case detection rate was extremely low.

    Science.gov (United States)

    Rahayu, Sri Ratna; Katsuyama, Hironobu; Demura, Masashi; Katsuyama, Midori; Ota, Yoko; Tanii, Hideji; Higashi, Tomomi; Semadi, Ngakan Putu Djaja; Saijoh, Kiyofumi

    2015-07-01

    Indonesia is ranked as the 4th highest contributor to tuberculosis (TB) in the world. Semarang District in Central Java displays extremely low case detection rate (CDR), possibly contributing to the local prevalence of TB. A case-control study was performed to explore the factors that cause such low CDR. We recruited 129 TB cases and 83 controls that visited the same centers and were not diagnosed with TB. The cases had 7.5 ± 2.3 symptoms/person on average, indicating the delay in diagnosis because the controls only displayed 1.0 ± 1.7. The multiple logistic regression analysis comparing the cases/controls extracted following factors as a risk to have TB: farmer, close contact with TB patients, ignorance of whether Bacillus Calmette-Guérin (BCG) was accepted or no, smoking, low income, a lot of people living in the same room, irregular hand wash before meals, not wash hands after blow, soil floor, and no sunlight and no ventilation in the house. Neither the cases nor the controls knew the symptoms and how to avoid TB infection, which probably caused the delay in diagnosis. It is difficult to change the current living conditions. Thus, the amendment of the community-based education program of TB seems to be required.

  6. Case and Administrative Support Tools

    Science.gov (United States)

    Case and Administrative Support Tools (CAST) is the secure portion of the Office of General Counsel (OGC) Dashboard business process automation tool used to help reduce office administrative labor costs while increasing employee effectiveness. CAST supports business functions which rely on and store Privacy Act sensitive data (PII). Specific business processes included in CAST (and respective PII) are: -Civil Rights Cast Tracking (name, partial medical history, summary of case, and case correspondance). -Employment Law Case Tracking (name, summary of case). -Federal Tort Claims Act Incident Tracking (name, summary of incidents). -Ethics Program Support Tools and Tracking (name, partial financial history). -Summer Honors Application Tracking (name, home address, telephone number, employment history). -Workforce Flexibility Initiative Support Tools (name, alternative workplace phone number). -Resource and Personnel Management Support Tools (name, partial employment and financial history).

  7. Caseload management, work-related stress and case manager self-efficacy among Victorian mental health case managers.

    Science.gov (United States)

    King, Robert

    2009-05-01

    In Australia and comparable countries, case management has become the dominant process by which public mental health services provide outpatient clinical services to people with severe mental illness. There is recognition that caseload size impacts on service provision and that management of caseloads is an important dimension of overall service management. There has been little empirical investigation, however, of caseload and its management. The present study was undertaken in the context of an industrial agreement in Victoria, Australia that required services to introduce standardized approaches to caseload management. The aims of the present study were therefore to (i) investigate caseload size and approaches to caseload management in Victoria's mental health services; and (ii) determine whether caseload size and/or approach to caseload management is associated with work-related stress or case manager self-efficacy among community mental health professionals employed in Victoria's mental health services. A total of 188 case managers responded to an online cross-sectional survey with both purpose-developed items investigating methods of case allocation and caseload monitoring, and standard measures of work-related stress and case manager personal efficacy. The mean caseload size was 20 per full-time case manager. Both work-related stress scores and case manager personal efficacy scores were broadly comparable with those reported in previous studies. Higher caseloads were associated with higher levels of work-related stress and lower levels of case manager personal efficacy. Active monitoring of caseload was associated with lower scores for work-related stress and higher scores for case manager personal efficacy, regardless of size of caseload. Although caseloads were most frequently monitored by the case manager, there was evidence that monitoring by a supervisor was more beneficial than self-monitoring. Routine monitoring of caseload, especially by a workplace

  8. Improvement of Students’ Ability to Analyzing Cases on Case Studies Through Journal and Learning Log

    Directory of Open Access Journals (Sweden)

    Riska Ahmad

    2017-08-01

    Full Text Available The purpose of this research is to improve the ability of students in guidance and counseling  to  analyzing the case through journals and learning logs This research is classroom action research consists of two cycles. The research phase consisted of planning, implementation, observation and reflection. The research subject are students in guidance and counseling while they are in sixth semester, totaling 20 people who were taking courses in Case Study. The research instrument is the observation guidelines, assessment rubrics and documentation of case studies in the form of journals and learning logs, and case study reports. The study was conducted collaboratively with student magister’s program guidance and counseling. The results showed that in cycle 1 students are able to identify cases, to develop ideas about the case, select and use instruments to analyze the cause of the problem. The results of the research cycle 2, showed 17 of the 20 students were able to analyze the cause of the problem, select the type of service and provide appropriate assistance in accordance with problem cases. Overall value obtained by the students in the subject of Case Studies also increased. In terms of the ability of explanation of the concept, the concept of truth and creativity, based on the ratings given by fellow students of average ability students were in either category, although there is less good, as are associated with the activity of the opinion and the quality of the opinions expressed.

  9. Conversion of wet glass to melt at lower seismogenic zone conditions: Implications for pseudotachylyte creep

    Science.gov (United States)

    Proctor, Brooks; Lockner, David A.; Lowenstern, Jacob B.; Beeler, Nicholas M.

    2018-01-01

    Coseismic frictional melting and the production of quenched glass called pseudotachylyte is a recurring process during earthquakes. To investigate how glassy materials affect the postseismic strength and stability of faults, obsidian gouges were sheared under dry and wet conditions from 200°C to 300°C at ~150 MPa effective normal stress. Dry glass exhibited a brittle rheology at all conditions tested, exhibiting friction values and microstructures consistent with siliciclastic materials. Likewise, wet glass at 200°C exhibited a brittle rheology. In contrast, wet gouges at 300°C transitioned from brittle sliding to linear‐viscous (Newtonian) flow at strain rates water was the dominant process reducing the viscosity and promoting viscous flow. As much as 5 wt % water diffused into the glass. These results may provide insight into postseismic‐slip behaviors and challenge some interpretations of fault kinematics based on studies assuming that pseudotachylyte formation and flow is solely coseismic.

  10. Grain temperature, radiation pressure and electric potential in the vicinity of main sequence and white dwarf stars

    Energy Technology Data Exchange (ETDEWEB)

    Leiknes, J.; Havnes, O. (University of Tromso, Auroral Observatory (Norway))

    1984-08-01

    We present results of calculations of the grain physical parameters temperature, lifetime against evaporation, radiation pressure and electric potential for spherical grains near main sequence stars, hydrogen type (DA) white dwarfs and helium type (DB) white dwarfs. These parameters are essential in determining the behaviour of grains near such stars. The grain temperature as a function of stellar distance is calculated for grains of sizes 0.1 and 1 ..mu.. (micron) for grain materials of silicate (obsidian), iron and graphite. The lifetime due to thermal evaporation as a function of grain temperature of these materials is also given. The radiation pressure is given for grain sizes from 0.01 to 10 ..mu.. for the same three grain materials. Grain potentials have been calculated as functions of stellar distance for one photoelectron high yield material (silicate) and one low yield material (graphite) for grains of radius 0.1 ..mu.. embedded in a thermal plasma of temperature T = 10/sup 4/ K.

  11. Orbital Evolution of Dust Particles in the Sublimation Zone near the Sun

    Science.gov (United States)

    Shestakova, L. I.; Demchenko, B. I.

    2018-03-01

    We have performed the calculations of the orbital evolution of dust particles from volcanic glass ( p-obsidian), basalt, astrosilicate, olivine, and pyroxene in the sublimation zone near the Sun. The sublimation (evaporation) rate is determined by the temperature of dust particles depending on their radius, material, and distance to the Sun. All practically important parameters that characterize the interaction of spherical dust particles with the radiation are calculated using the Mie theory. The influence of radiation and solar wind pressure, as well as the Poynting-Robertson drag force effects on the dust dynamics, are also taken into account. According to the observations (Shestakova and Demchenko, 2016), the boundary of the dust-free zone is 7.0-7.6 solar radii for standard particles of the zodiacal cloud and 9.1-9.2 solar radii for cometary particles. The closest agreement is obtained for basalt particles and certain kinds of olivine, pyroxene, and volcanic glass.

  12. Variation in Rapa Nui (Easter Island) land use indicates production and population peaks prior to European contact.

    Science.gov (United States)

    Stevenson, Christopher M; Puleston, Cedric O; Vitousek, Peter M; Chadwick, Oliver A; Haoa, Sonia; Ladefoged, Thegn N

    2015-01-27

    Many researchers believe that prehistoric Rapa Nui society collapsed because of centuries of unchecked population growth within a fragile environment. Recently, the notion of societal collapse has been questioned with the suggestion that extreme societal and demographic change occurred only after European contact in AD 1722. Establishing the veracity of demographic dynamics has been hindered by the lack of empirical evidence and the inability to establish a precise chronological framework. We use chronometric dates from hydrated obsidian artifacts recovered from habitation sites in regional study areas to evaluate regional land-use within Rapa Nui. The analysis suggests region-specific dynamics including precontact land use decline in some near-coastal and upland areas and postcontact increases and subsequent declines in other coastal locations. These temporal land-use patterns correlate with rainfall variation and soil quality, with poorer environmental locations declining earlier. This analysis confirms that the intensity of land use decreased substantially in some areas of the island before European contact.

  13. Middle palaeolithic and neolithic occupations around Mundafan Palaeolake, Saudi Arabia: implications for climate change and human dispersals.

    Directory of Open Access Journals (Sweden)

    Rémy Crassard

    Full Text Available The Arabian Peninsula is a key region for understanding climate change and human occupation history in a marginal environment. The Mundafan palaeolake is situated in southern Saudi Arabia, in the Rub' al-Khali (the 'Empty Quarter', the world's largest sand desert. Here we report the first discoveries of Middle Palaeolithic and Neolithic archaeological sites in association with the palaeolake. We associate the human occupations with new geochronological data, and suggest the archaeological sites date to the wet periods of Marine Isotope Stage 5 and the Early Holocene. The archaeological sites indicate that humans repeatedly penetrated the ameliorated environments of the Rub' al-Khali. The sites probably represent short-term occupations, with the Neolithic sites focused on hunting, as indicated by points and weaponry. Middle Palaeolithic assemblages at Mundafan support a lacustrine adaptive focus in Arabia. Provenancing of obsidian artifacts indicates that Neolithic groups at Mundafan had a wide wandering range, with transport of artifacts from distant sources.

  14. FORMATION PROCESS AND HISTORICAL FUNCTIONS OF OLD AKIHA ROAD

    Science.gov (United States)

    Nakane, Yoji; Okuda, Masao; Kani, Yukihiko; Hayakawa, Kiyoshi; Matsui, Tamotsu

    An object of this study is the old Akiha road located along the southern parts of the Akaishi Mountains in Sizuoka Prefecture. The old Akiha road between Hamamatsu city in Enshu and Iida city in Shinshu had been utilized by people for the purposes of making a pilgrimage, megalithic faith, transporting obsidian since the primitive age, practicing the mountaineering asceticism, operating the military activities in the warlike age, transporting salt from coastal area to mountainous area and so on. Through the investigation of literature, site reconnaissance and hearing, the formation process and the historical functions of the old Akiha road were studied, including the situation in medieval times or before. As the results, it was elucidated that the oldest road between two cities had located over the Hyoukoshi Pass, the road routes had the lowering trend from mountainside to riverside, and the historical functions of old Akiha road were the passage for transportation of various kinds of goods and human being, faith and culture.

  15. Isolation of a hyperthermophilic archaeum predicted by in situ RNA analysis.

    Science.gov (United States)

    Huber, R; Burggraf, S; Mayer, T; Barns, S M; Rossnagel, P; Stetter, K O

    1995-07-06

    A variety of hyperthermophilic bacteria and archaea have been isolated from high-temperature environments by plating and serial dilutions. However, these techniques allow only the small percentage of organisms able to form colonies, or those that are predominant within environmental samples, to be obtained in pure culture. Recently, in situ 16S ribosomal RNA analyses of samples from the Obsidian hot pool at Yellowstone National Park, Wyoming, revealed a variety of archaeal sequences, which were all different from those of previously isolated species. This suggests substantial diversity of archaea with so far unknown morphological, physiological and biochemical features, which may play an important part within high-temperature ecosystems. Here we describe a procedure to obtain pure cultures of unknown organisms harbouring specific 16S rRNA sequences identified previously within the environment. It combines visual recognition of single cells by phylogenetic staining and cloning by 'optical tweezers'. Our result validates polymerase chain reaction data on the existence of large archael communities.

  16. 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.

  17. Longwave thermal infrared spectral variability in individual rocks

    Energy Technology Data Exchange (ETDEWEB)

    Balick, Lee K [Los Alamos National Laboratory; Gillespie, Alan [UN. WASHINGTON; French, Andrew [USDA-ARS; Danilina, Iryna [UN. WASHINGTON

    2008-01-01

    A hyperspectral imaging spectrometer measuring in the longwave thermal infrared (7.6-11.6 {micro}m) with a spatial resolution less than 4 mm was used in the field to observe the variability of emissivity spectra within individual rocks. The rocks were obtained commercially, were on the order of 20 cm in size and were selected to have distinct spectral features: they include alabaster (gypsum), soapstone (steatite with talc), obsidian (volcanic glass), norite (plagioclase and orthopyroxene), and 'jasper' (silica with iron oxides). The advantages of using an imaging spectrometer to spectrally characterize these rocks are apparent. Large spectral variations were observed within individual rocks that may be attributed to roughness, surface geometry, and compositional variation. Non-imaging spectrometers would normally miss these variations as would small samples used in laboratory measurements, spatially averaged spectra can miss the optimum spectra for identification materials and spatially localized components of the rock can be obscured.

  18. Firm contracts for treatability tests on contaminated soils

    International Nuclear Information System (INIS)

    Anon.

    1989-01-01

    Geosafe Corporation, a Pacific Northwest-headquartered hazardous waste remediation company, announced that is has successfully completed treatability testing of contaminated soils under contract with Woodward Clyde Consultants of Denver, Colorado, the prime contractor for a major hazardous waste site in the Western United States. The tests are being conducted at the University of Washington with Geosafe's specially-designed test equipment. The recently concluded testing confirms the ability of Geosafe's patented in situ vitrification (ISV) technology to treat soils containing a variety of organic and inorganic contaminants. ISV, for which Geosafe has worldwide rights, is the only technology available today that will fully comply with the Superfund Amendments and Reauthorization Act. The ability of ISV to treat mixtures of organic, inorganic and radioactive wastes in situ, in a single process, offers distinct advantages over excavation, transportation and incineration. During the ISV process, organic contaminants are pyrolized and the inorganics present are chemically incorporated into the molten soil which, when cooled, resembles naturally-occurring obsidian

  19. Genetic Engineering and Sustainable Crop Disease Management: Opportunities for Case-by-Case Decision-Making

    Directory of Open Access Journals (Sweden)

    Paul Vincelli

    2016-05-01

    Full Text Available Genetic engineering (GE offers an expanding array of strategies for enhancing disease resistance of crop plants in sustainable ways, including the potential for reduced pesticide usage. Certain GE applications involve transgenesis, in some cases creating a metabolic pathway novel to the GE crop. In other cases, only cisgenessis is employed. In yet other cases, engineered genetic changes can be so minimal as to be indistinguishable from natural mutations. Thus, GE crops vary substantially and should be evaluated for risks, benefits, and social considerations on a case-by-case basis. Deployment of GE traits should be with an eye towards long-term sustainability; several options are discussed. Selected risks and concerns of GE are also considered, along with genome editing, a technology that greatly expands the capacity of molecular biologists to make more precise and targeted genetic edits. While GE is merely a suite of tools to supplement other breeding techniques, if wisely used, certain GE tools and applications can contribute to sustainability goals.

  20. Shared written case formulations and weight change in outpatient therapy for anorexia nervosa: a naturalistic single case series.

    Science.gov (United States)

    Gladwin, Alice M; Evangeli, Michael

    2013-01-01

    The therapeutic effects of written shared case formulations are underexplored and have not been examined in anorexia nervosa. This study explored the relationship between (a) the delivery (b) the quality of a shared written case formulation and weight in outpatient psychological therapy for anorexia nervosa. A naturalistic single case series approach was used to examine the case notes of women who had attended a specialist eating disorders service over a 2-year period. The case notes of 15 adult women who had undergone outpatient psychological therapy for anorexia nervosa with a shared written case formulation component were reviewed. The impact of the quality of the case formulation on weekly weight was examined for 14 of the clients where the case formulation was available. The nature of the relationship between the delivery of the written shared case formulation and weight was examined for all 15 clients. There was some evidence to support an association between delivery of the shared written case formulation and weight changes (both weight gain [five out of 15 clients] and weight loss [three out of 15 clients]) in individual cases. Higher case formulation quality was related to cases where weight change did not occur. The delivery of case formulations can be associated with important therapeutic change (both beneficial and potentially harmful) in anorexia nervosa. Future research into the causal mechanisms associated with sharing formulations will face the challenge of adopting strategies that allow for an in-depth exploration of complex therapy variables whilst overcoming methodological challenges. Copyright © 2012 John Wiley & Sons, Ltd.

  1. Case-based medical informatics

    Directory of Open Access Journals (Sweden)

    Arocha José F

    2004-11-01

    Full Text Available Abstract Background The "applied" nature distinguishes applied sciences from theoretical sciences. To emphasize this distinction, we begin with a general, meta-level overview of the scientific endeavor. We introduce the knowledge spectrum and four interconnected modalities of knowledge. In addition to the traditional differentiation between implicit and explicit knowledge we outline the concepts of general and individual knowledge. We connect general knowledge with the "frame problem," a fundamental issue of artificial intelligence, and individual knowledge with another important paradigm of artificial intelligence, case-based reasoning, a method of individual knowledge processing that aims at solving new problems based on the solutions to similar past problems. We outline the fundamental differences between Medical Informatics and theoretical sciences and propose that Medical Informatics research should advance individual knowledge processing (case-based reasoning and that natural language processing research is an important step towards this goal that may have ethical implications for patient-centered health medicine. Discussion We focus on fundamental aspects of decision-making, which connect human expertise with individual knowledge processing. We continue with a knowledge spectrum perspective on biomedical knowledge and conclude that case-based reasoning is the paradigm that can advance towards personalized healthcare and that can enable the education of patients and providers. We center the discussion on formal methods of knowledge representation around the frame problem. We propose a context-dependent view on the notion of "meaning" and advocate the need for case-based reasoning research and natural language processing. In the context of memory based knowledge processing, pattern recognition, comparison and analogy-making, we conclude that while humans seem to naturally support the case-based reasoning paradigm (memory of past experiences

  2. Five misunderstandings about Case-study Research

    DEFF Research Database (Denmark)

    Flyvbjerg, Bent

    This article examines five common misunderstandings about case-study research: (1) Theoretical knowledge is more valuable than practical knowledge; (2) One cannot generalize from a single case, therefore the single case study cannot contribute to scientific development; (3) The case study is most...... useful for generating hypotheses, while other methods aremore suitable for hypotheses testing and theory building; (4) The case study contains a bias toward verification; and (5) It is often difficult to summarize specific case studies. The article explains and corrects these misunderstandings one by one...... and concludes with the Kuhnian insight that a scientific discipline without a large number of thoroughly executed case studies is a discipline without systematic production of exemplars, and that a discipline without  exemplars is an ineffective one. Social science may be strengthened by the execution of more...

  3. First case of bacteremia caused by Moellerella wisconsensis: case report and a review of the literature.

    Science.gov (United States)

    Cardentey-Reyes, A; Jacobs, F; Struelens, M J; Rodriguez-Villalobos, H

    2009-12-01

    Moellerella wisconsensis, a member of the Enterobacteriaceae family, is rarely isolated in clinical specimens. We report here a case of M. wisconsensis infection in a 46-year-old cirrhotic patient with acute cholecystitis. This is the first reported case of a M. wisconsensis infection in Belgium and the first reported case of human bacteremia caused by this bacterium. Our case report is followed by a review of the literature.

  4. Dioctophymiasis: A Rare Case Report.

    Science.gov (United States)

    Chauhan, Sapna; Kaval, Sunil; Tewari, Swati

    2016-02-01

    Dioctophyma renale commonly known as "giant kidney worm' is found in the kidney of carnivorous mammals. Human infestation is rare, but results in destruction of the kidneys. Very few cases have been reported worldwide. We are here reporting a case of Dioctophymiasis in a 35-year-old male patient who presented with retention of urine and subsequent passage of worm and blood in urine. The worm was confirmed as Dioctophyma renale based on its morphology and clinical presentation. This is a very rare case report and to best of our knowledge only two cases have been reported from India.

  5. Urachal endometrioma: a case report.

    LENUS (Irish Health Repository)

    Browne, Katherine M

    2009-01-01

    INTRODUCTION: We discuss a rare presentation of an unusual case of endometrioma. CASE PRESENTATION: A 40-year-old Caucasian woman presented with subacute abdominal pain and a suprapubic mass. A final diagnosis was made after the mass was resected and histopathology confirmed an endometrioma originating from an urachal remnant. Select imaging studies and histopathology are presented in this case report. CONCLUSION: While endometriomata are well known to arise from abdominal scars, the condition described in this case report is a rare example of an endometrioma arising from the urachus. A review of the pathological complications of the urachus is also included.

  6. [Urogenital tuberculosis. Apropos of 40 cases].

    Science.gov (United States)

    el Khader, K; el Fassi, J; Karmouni, T; Tazi, K; Ibnattya, A; Hachimi, M; Lakrissa, A

    1997-01-01

    The authors report a series of 40 cases of genitourinary tuberculosis diagnosed and treated in the department of urology "B" of Avicenne hospital over a 7-year period. The objective of this study is to define the various diagnostic and therapeutic aspects of this disease. The patients were predominantly males (62.5%) with a mean age of 40 years. 25% of cases reported a history of extra-urinary tuberculosis. The very polymorphous clinical presentation is dominated by signs of cystitis (45%). Intravenous urography is frequently suggestive of the diagnosis based on the appearance and multiplicity of the lesions. The radiological lesions most frequently encountered were silent kidney (19 cases) and small tuberculous bladder (11 cases). The definitive diagnosis was established by pathological examination in 38 cases (biopsies, operative specimens, prostatic resection chips) and/or by demonstration of AFB in 2 cases (urine, pus). Tuberculostatic treatment was administered to all patients, either alone (5 cases) or, more usually, in combination with surgical and/or endo-urological treatment (35 cases), reflecting the magnitude and severity of the destructive and scar lesions.

  7. Medico-legal findings, legal case progression, and outcomes in South African rape cases: retrospective review.

    Directory of Open Access Journals (Sweden)

    Rachel Jewkes

    2009-10-01

    Full Text Available BACKGROUND: Health services for victims of rape are recognised as a particularly neglected area of the health sector internationally. Efforts to strengthen these services need to be guided by clinical research. Expert medical evidence is widely used in rape cases, but its contribution to the progress of legal cases is unclear. Only three studies have found an association between documented bodily injuries and convictions in rape cases. This article aims to describe the processing of rape cases by South African police and courts, and the association between documented injuries and DNA and case progression through the criminal justice system. METHODS AND FINDINGS: We analysed a provincially representative sample of 2,068 attempted and completed rape cases reported to 70 randomly selected Gauteng province police stations in 2003. Data sheets were completed from the police dockets and available medical examination forms were copied. 1,547 cases of rape had medical examinations and available forms and were analysed, which was at least 85% of the proportion of the sample having a medical examination. We present logistic regression models of the association between whether a trial started and whether the accused was found guilty and the medico-legal findings for adult and child rapes. Half the suspects were arrested (n = 771, 14% (209 of cases went to trial, and in 3% (31 of adults and 7% (44 of children there was a conviction. A report on DNA was available in 1.4% (22 of cases, but the presence or absence of injuries were documented in all cases. Documented injuries were not associated with arrest, but they were associated with children's cases (but not adult's going to trial (adjusted odds ratio [AOR] for having genital and nongenital injuries 5.83, 95% confidence interval [CI] 1.87-18.13, p = 0.003. In adult cases a conviction was more likely if there were documented injuries, whether nongenital injuries alone AOR 6.25 (95% CI 1.14-34.3, p = 0

  8. Theory testing using case studies

    DEFF Research Database (Denmark)

    Dissing Sørensen, Pernille; Løkke Nielsen, Ann-Kristina

    2006-01-01

    on the strengths of theory-testing case studies. We specify research paths associated with theory testing in case studies and present a coherent argument for the logic of theoretical development and refinement using case studies. We emphasize different uses of rival explanations and their implications for research...... design. Finally, we discuss the epistemological logic, i.e., the value to larger research programmes, of such studies and, following Lakatos, conclude that the value of theory-testing case studies lies beyond naïve falsification and in their contribution to developing research programmes in a progressive......Case studies may have different research goals. One such goal is the testing of small-scale and middle-range theories. Theory testing refers to the critical examination, observation, and evaluation of the 'why' and 'how' of a specified phenomenon in a particular setting. In this paper, we focus...

  9. Estimating time-varying exposure-outcome associations using case-control data: logistic and case-cohort analyses

    Directory of Open Access Journals (Sweden)

    Ruth H. Keogh

    2016-01-01

    Full Text Available Abstract Background Traditional analyses of standard case-control studies using logistic regression do not allow estimation of time-varying associations between exposures and the outcome. We present two approaches which allow this. The motivation is a study of vaccine efficacy as a function of time since vaccination. Methods Our first approach is to estimate time-varying exposure-outcome associations by fitting a series of logistic regressions within successive time periods, reusing controls across periods. Our second approach treats the case-control sample as a case-cohort study, with the controls forming the subcohort. In the case-cohort analysis, controls contribute information at all times they are at risk. Extensions allow left truncation, frequency matching and, using the case-cohort analysis, time-varying exposures. Simulations are used to investigate the methods. Results The simulation results show that both methods give correct estimates of time-varying effects of exposures using standard case-control data. Using the logistic approach there are efficiency gains by reusing controls over time and care should be taken over the definition of controls within time periods. However, using the case-cohort analysis there is no ambiguity over the definition of controls. The performance of the two analyses is very similar when controls are used most efficiently under the logistic approach. Conclusions Using our methods, case-control studies can be used to estimate time-varying exposure-outcome associations where they may not previously have been considered. The case-cohort analysis has several advantages, including that it allows estimation of time-varying associations as a continuous function of time, while the logistic regression approach is restricted to assuming a step function form for the time-varying association.

  10. Cases for the Net Generation: An Empirical Examination of Students' Attitude toward Multimedia Case Studies

    Science.gov (United States)

    Sheppard, Michael; Vibert, Conor

    2016-01-01

    Case studies have been an important tool in business, legal, and medical education for generations of students. Traditional text-based cases tend to be self-contained and structured in such a way as to teach a particular concept. The multimedia cases introduced in this study feature unscripted web-hosted video interviews with business owners and…

  11. Radiological case

    International Nuclear Information System (INIS)

    Giraldo Estrada, Horacio

    2001-01-01

    The paper analyze the case of a patient (65 year-old) masculine, who consults for precordial pain associated to dyspnoea, left scapular pain and in the shoulder of the same side, of 3 days of evolution that it has been permanent and progressive. He also refers, loss of weight the last 6 months and dyspnoea of effort of 1 month of evolution. He denies chill, fever, cough or expectoration. The patient presents gastric ulcer tried for 1 year, smoker of 2 packages of daily cigarettes of the 15 to the 40 years; all its life worked in masonry. X-rays of the thorax and Tac, among other analyses were done and the case is discusses

  12. Electromagnetic fields in cased borehole

    International Nuclear Information System (INIS)

    Lee, Ki Ha; Kim, Hee Joon; Uchida, Toshihiro

    2001-01-01

    Borehole electromagnetic (EM) measurements, using fiberglass-cased boreholes, have proven useful in oil field reservoir characterization and process monitoring (Wilt et al., 1995). It has been presumed that these measurements would be impossible in steel-cased wells due to the very large EM attenuation and phase shifts. Recent laboratory and field studies have indicated that detection of EM signals through steel casing should be possible at low frequencies, and that these data provide a reasonable conductivity image at a useful scale. Thus, we see an increased application of this technique to mature oilfields, and an immediate extension to geothermal industry as well. Along with the field experiments numerical model studies have been carried out for analyzing the effect of steel casing to the EM fields. The model used to be an infinitely long uniform casing embedded in a homogeneous whole space. Nevertheless, the results indicated that the formation signal could be accurately recovered if the casing characteristics were independently known (Becker et al., 1998; Lee el al., 1998). Real steel-cased wells are much more complex than the simple laboratory models used in work to date. The purpose of this study is to develop efficient numerical methods for analyzing EM fields in realistic settings, and to evaluate the potential application of EM technologies to cross-borehole and single-hole environment for reservoir characterization and monitoring

  13. Bioremediation case studies: Abstracts. Final report

    International Nuclear Information System (INIS)

    Devine, K.

    1992-03-01

    The report contains abstracts of 132 case studies of bioremediation technology applied to hazardous waste clean-up. It was prepared to compile bioremediation studies in a variety of locations and treating diverse contaminants, most of which were previously undocumented. All data are based on vendor-supplied information and there was no opportunity to independently confirm its accuracy. These 132 case studies, from 10 different biotechnology companies, provide users with reference information about on-going and/or completed field applications and studies. About two-thirds of the cases were at full-scale clean-up level with the remainder at pilot or laboratory scale. In 74 percent of the cases, soil was at least one of the media treated. Soil alone accounts for 46 percent of the cases. Petroleum-related wastes account for the largest contaminant with 82 cases. Thirty-one states are represented in the case studies

  14. How To Set Up Your Own Small Business. Service Company Case Study. Manufacturing Firm Case Study. Retail Store Case Study.

    Science.gov (United States)

    Fallek, Max

    This collection of case studies is intended for use in a course in setting up a small business. The first, a case study of the process of setting up a service company, covers analyzing the pros and cons of starting one's own business, assessing the competition and local market, and selecting a site for and financing the business. The principal…

  15. The role of radionuclide studies in emergency cases

    International Nuclear Information System (INIS)

    Nishimura, Tsunehiko; Hayashida, Kohei; Uehara, Toshiisa

    1982-01-01

    Radionuclide studies have been performed popularly because of its noninvasive and simple method recently. In this study, we applied this technique for the evaluation of emergency cases in cardiovascular diseases. There were 93 cases (1.5%) out of 6163 cases, done during 1981. The subjects were 34 cases of cardiac studies (9 cases of sup(99m)Tc-PYP myocardial imaging, 12 cases of thallium myocardial imaging, 13 cases of cardioangiography), 23 cases of peripheral diseases (12 cases of peripheral angiography, 11 cases of venography), 16 cases of pulmonary imaging, 10 cases of renal studies (6 cases of renal angiography, 9 cases of renal imaging) and 5 cases of brain angiography. These studies were proven to be useful clinically for the evaluation of emergency cases and follow-up studies. In the near future, ''emergency radionuclide studies'' would be benefit for the high-risk patients noninvasively. (author)

  16. Case Briefs in Legal English Classes

    Directory of Open Access Journals (Sweden)

    Bilová Stĕpánka

    2016-06-01

    Full Text Available A case brief can be described as a succinct summary of a case which specifies the facts, procedural history, legal issue(s, court decision and legal reasoning supporting the judgment, even though exact formats may vary. Case briefing is a demanding activity which is required from students during their law studies. The goal is to teach students to focus on the essential parts of the case and to obtain a thorough understanding of the case and the reasoning, which means the students need to employ their analytical and critical thinking skills.

  17. Rhetorical Structure and Linguistic Features of Case Presentations in Case Reports in Taiwanese and International Medical Journals

    Science.gov (United States)

    Hung, Hsuan; Chen, Pi-Ching; Tsai, Jing-Jane

    2012-01-01

    The case presentation is the core section of a medical case report. Issues in the teaching of case report writing have recently been the subject of great interest in medical education, especially in the era of globalization. Given that Taiwanese medical students, residents and junior physicians are requested to write case reports in English and…

  18. Case histories as evidence.

    Science.gov (United States)

    Herxheimer, Andrew; Healy, David; Menkes, David B

    2012-01-01

    In courts case histories play a central part when a crime may have resulted from an effect of a prescribed drug; in civil cases where a person may have suffered damage from a drug; and in coroners' enquiries into the cause of unexplained deaths. The court must decide two important questions: 1. Can the suspected medication(s) cause this kind of effect? 2. Did it (or they) do so in this particular case? Many judges and coroners have not addressed these questions clearly and have not used expert witnesses consistently, on occasion disregarding scientific evidence. Courts need to appoint experts to explain and interpret the scientific evidence. Few judges are equipped to resolve contradictions between different experts. Brief accounts of five cases from four countries illustrate these points. The reluctance of legal processes to implicate drugs as a possible cause of violent behaviour leads to injustice. Courts must be required to obtain appropriate expert evidence, and be given independent data on which drugs can cause such behaviour.

  19. [The case manager--from words to deeds?].

    Science.gov (United States)

    Lindegaard, Birthe Rosenkrantz; Qvist, Peter

    2010-04-19

    Allocation of a case manager is now mandatory for both in- and outpatients in Denmark. Case manager allocation is reported quarterly to the regions and results are generally satisfying. Knowledge about fulfillment of the case manager role is, however, sparse. This study aims to examine the degree of fulfillment of the case manager role for a sample of inpatients. Two medical and two surgical wards participated. Patients were interviewed in relation to discharge while staff assigned as case managers completed a survey. Both patients and case managers answered questions regarding the defined roles as case managers: Planning/coordination, continuous information and discharge planning. 107 of 125 eligible patients were interviewed. Only 25 declared themselves informed about the allocation of a case manager. The patients' assessment of the service provided by the staff in relation to case manager tasks was generally good, but the services were seldom provided by the named case manager. 22% of patients did not experience continuous information, while only 13% did not experience a generally coherent stay in hospital. 110 case managers completed the survey. Less than half felt themselves well informed about the case manager role. Only a few case managers feel that they succeed in fulfilling the role, particularly regarding the participation in discharge planning. There seems to be a need for a targeted effort to improve the conditions for case managers in Danish hospitals in order to meet the intentions of this initiative.

  20. BioFleet case studies

    International Nuclear Information System (INIS)

    2007-01-01

    These six case studies examined the use of different biodiesel blends as fuel supply sources for businesses in British Columbia (BC). In the first case study, 6 municipalities participated in a pilot program designed to compare the performance of biodiesel and diesel fuels. Each municipality operated 2 base vehicles running on conventional diesel along with 2 similar vehicles which used biodiesel. Real time emissions tests and analyses of the vehicles using biodiesel were also conducted by 2 of the participating municipalities. All municipalities participating in the study agreed to purchase significant volumes of biodiesel. The second case study described a pilot study conducted by the City of Vancouver's equipment services branch in 2004. As a result of the study, the city now has over 530 types of equipment that use biodiesel. The third case study described a program designed by TSI Terminals in Vancouver to assess the emission reduction impact of using biodiesel at its port facility. Six different pieces of equipment were used to confirm that biodiesel could be used throughout the terminal. Test results confirmed that biodiesel blends could be used to reduce emissions. Overall emissions were reduced by 30 per cent. The fourth case study described a waste renderer that used a fleet of 36 trucks to deliver raw products to its plants. The company made the decision to use only biodiesel for its entire fleet of trucks. Since July 2005, the company has logged over 1.7 million km using biodiesel blends. The fifth case study described a salmon hatchery that switched from diesel to biodiesel in order to reduce emissions. The biodiesel blends are used to fuel the hatchery's 2 diesel generators. The hatchery has reduced emissions of greenhouse gases (GHGs) by an estimated 1800 tonnes annually. The sixth case study described how the Township of Langley has started using biodiesel for its entire fleet of of approximately 250 pieces of equipment. The township has not

  1. Case-based Agile Fixture Design

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In order to realize the agility of the fixture design, such asreconfigurability, rescalability and reusability, fixture structure is function unit-based decomposed from a fire-new point of view. Which makes it easy for agile fixture to be reconfigured and modified. Thereby, the base of case-based agile fixture design system info is established.Whole case-based agile fixture design model is presented. In which, three modules are added relative to the other models, including case matching of fixture planning module, conflict arbitration module and agile fixture case modify module. The three modules could solve the previous problem that the experience and result are difficult to be reused in the process of design.Two key techniques in the process of the agile fixture design, the evaluation of case similarity, and restriction-based conflict arbitration, are listed. And some methods are presented to evaluate the similarity and clear up the conflict.

  2. Endodontic cellulitis 'flare-up'. Case report.

    Science.gov (United States)

    Matusow, R J

    1995-02-01

    Endodontic cellulitis involves facial swelling which can vary from mild to severe and can occur as a primary case or a flare-up following initial treatment of asymptomatic teeth with periapical lesions. The microbial spectrum in primary cases involves a significant mixture of anaerobic and facultative aerobic microbes, chiefly streptococci. In a previous study, cultures from flare-up cases, utilizing the same anaerobic techniques as in primary cases, revealed an absence of obligate anaerobes and an 80 per cent incidence of facultative aerobic streptococci. These cases also revealed a significant time lapse from onset of symptoms to the cellulitis phase. No sex or age factors were noted in the primary or flare-up cases. The purpose of this case report is to restate a traditional theory, namely, the alteration of the oxidation/reduction potential (Eh), as a major factor for endodontic cellulitis flare-ups; to confirm the pathogenic potential of oral facultative streptococci; and that asymptomatic endodontic lesions tend to exist with mixed aerobic/anaerobic microbial flora.

  3. Fuzzy-Set Case Studies

    Science.gov (United States)

    Mikkelsen, Kim Sass

    2017-01-01

    Contemporary case studies rely on verbal arguments and set theory to build or evaluate theoretical claims. While existing procedures excel in the use of qualitative information (information about kind), they ignore quantitative information (information about degree) at central points of the analysis. Effectively, contemporary case studies rely on…

  4. Case manager satisfaction in public health.

    Science.gov (United States)

    Schutt, Russell K; Fawcett, Jacqueline; Gall, Gail B; Harrow, Brooke; Woodford, Mary Lou

    2010-01-01

    The purpose of this study was to examine correlates of case managers' satisfaction with their work, services, and service network and to identify connections to service performance and service costs. A decentralized public health program that exemplifies the trend toward more diverse clients and networked services. A mixed method design with 34 case managers. As hypothesized, the case managers' experiences with clients and the service network, and their service effectiveness, were associated with their satisfaction with their jobs and the services they provide. Satisfaction was also positively associated with more timely service delivery. These associations were explained in part by case managers' education and training. Case managers can achieve high levels of job and service satisfaction in outreach programs serving a diverse client population in a decentralized service network. Case managers' job and service satisfaction improves with reduced service problems and service delays and when case managers can devise work-arounds for persistent service problems. Using advanced practice nurses (APN) and providing more on-the-job training may increase case manager satisfaction with their jobs and the services they provide. Special efforts may be needed to prevent a decline in job satisfaction with years of experience.

  5. Isolated adrenal paracoccidioidomycosis: Case report

    International Nuclear Information System (INIS)

    Uribe Castro, Jorge Ricardo; Quintana, Humberto; Puentes, Alix Sofia and others

    2011-01-01

    Even though paracoccidioidomycosis has a relatively high prevalence in Latin America in a systemic form, isolated cases, especially compromising the adrenal glands, are uncommon, with only two reported cases. In this article, we report the case of a 55 year-old male with clinical manifestations of adrenal insufficiency. The only imaging finding was the presence of bilateral adrenal masses. The biopsy showed Paracoccidioides brasiliensis infection.

  6. Case report

    African Journals Online (AJOL)

    abp

    2013-01-09

    . The electrolytes analysis revealed an acute hyponatremia. (sodium concentration 125 mmol/L). Medical treatment consisted of hypertonic saline solution 3%, volume expansion, intubation and ventilation. The presented case ...

  7. Case Report: A Rare Case Report of Frontal Lobe Syndrome

    Directory of Open Access Journals (Sweden)

    Morteza Nouri- Khajavi

    2003-04-01

    Full Text Available The frontal lobe syndrome is a permanent personality change disorder with characteristic clinical pictures, which followed by frontal lobes damage. Clinical picture include: Affective instability, recurrent aggressive behavior, impaired social judgment, apathy and undifferentiating or suspiciousness and paranoid ideations. According DSM-IV classification frontal lobe syndrome named personality change due to head trauma on Axis I. Herein we report a case of 46 years-old man, who has developed behavioral disturbances following head trauma, about 10 years ago. Main clinical figures in this case are apathy, avolition and, undifferentiating. Clinical pictures are constant during these 10 years. The diagnostic approach has been based on patient’s problems history which, has taken from his family, mental status examination, Neurological examination, Brain imaging and Neuropsychological assessments which related to frontal lobes function. Because of rarity & neglection due to mysterious function of frontal lobes, and also considering that personality change from previous level is prominent figure of this syndrome and also brain imaging findings, which compatible with clinical findings, with this aim, we have reported this case.

  8. CASE REPORT A recurrent gestational choriocarcinoma case ...

    African Journals Online (AJOL)

    Admin

    molar pregnancy (Luna Russo et al., 2015). To our knowledge recurrence resulting in rupture 14 month following a live pregnancy is an extremely rare event. Management of gestational trophoblastic disease in our setup poses multiple challenges as seen in this particular case. Serum β-HCG follow up for these patients ...

  9. What is in a Business Case? Business Cases as a Tool‐in‐Use for Promoting Water Stewardship

    DEFF Research Database (Denmark)

    Pedersen, Esben Rahbek Gjerdrum; Lauesen, Linne Marie; Rosati, Francesco

    This paper explores the role of business cases as a tool‐in‐use for decision‐making processes on Water management. The literature is rich on generic discussions of the business case for corporate sustainability, whereas there have been less efforts to examine the concrete use of business cases...... in everyday organisational life. Drawing on the practice‐based management literature, it is concluded that the business case tool has a decisive influence on water management activities among European food companies. However, the analysis also show the business case tool are not set in stone but can...

  10. Characteristics of sick-listing cases that physicians consider problematic--analyses of written case reports.

    Science.gov (United States)

    Engblom, Monika; Alexanderson, Kristina; Rudebeck, Carl Edvard

    2009-01-01

    The aim was to discern common characteristics in the sick-listing cases that physicians in general practice and occupational health services find problematic. Descriptive categorization within a narrative theoretical framework. Sickness-insurance course for physicians in general practice and occupational health services. A total of 195 case reports written by 195 physicians. Main outcome measures. Categories of features regarding medical, work, and social situation as well as medical interventions. Beside age and sex, the following information was often provided: family situation, stressful life events, occupation, problem at work, considerations concerning diagnoses, medical investigations, treatments, and vocational rehabilitation measures. Two-thirds of the patients had been sickness absent for more than a year. The most common type of case reports concerned women, employed in non-qualified nursing occupations, and sick listed due to mental disorders. The most common measures taken by the physicians were referrals to psychotherapy and/or physiotherapy, and prescribing antidepressants (SSRI). Facts about alcohol habits were rarely provided in the cases. Some of the circumstances, such as prolonged sick-listing, are likely to be more or less inevitable in problematic sick-listing cases. Other circumstances, such as stress-full life events, more closely reflect what the reporting physicians find problematic. The categories identified can be regarded as markers of problematic sick-listing cases in general practice and occupational health service.

  11. Selecting appropriate cases when tracing causal mechanisms

    DEFF Research Database (Denmark)

    Beach, Derek; Pedersen, Rasmus Brun

    2016-01-01

    The last decade has witnessed resurgence in the interest in studying the causal mechanisms linking causes and outcomes in the social sciences. This article explores the overlooked implications for case selection when tracing mechanisms using in-depth case studies. Our argument is that existing case...... selection guidelines are appropriate for research aimed at making cross-case claims about causal relationships, where case selection is primarily used to control for other causes. However, existing guidelines are not in alignment with case-based research that aims to trace mechanisms, where the goal...... is to unpack the causal mechanism between X and Y, enabling causal inferences to be made because empirical evidence is provided for how the mechanism actually operated in a particular case. The in-depth, within-case tracing of how mechanisms operate in particular cases produces what can be termed mechanistic...

  12. MRI case studies

    International Nuclear Information System (INIS)

    Huggett, S.; Barber, J.

    1989-01-01

    Three case studies are presented to show the value of magnetic resonance imaging used in conjunction with other imaging techniques. In each case MRI proved a vital diagnostic tool and superior to CT in showing firstly the haematoma in a patient with aphasia and right-sided weakness, secondly the size of the disc herniation in a patient with severe leg and ankle pains and thirdly the existence of a metastatic lesion in a patient with a previous history of breast cancer. 11 figs

  13. Case assessments for nuclear medicine registrars

    International Nuclear Information System (INIS)

    Farlow, D.

    1994-01-01

    Westmead Hospital set some of the recent nuclear medicine cases for registrar training. These case assessments have been completed by the registrars and he thought it might be interesting for the general nuclear medicine community to attempt the cases themselves and compare their answers with the model reports and patient follow-ups. Edited versions of two cases and model answers are presented. 35 refs

  14. Ulnar nerve lesion at the wrist and sport: A report of 8 cases compared with 45 non-sport cases.

    Science.gov (United States)

    Seror, P

    2015-04-01

    Reporting clinical and electrodiagnostic characteristics of sport-related ulnar neuropathies at the wrist. Eight sport-related and 45 non-sport-related cases from 53 ulnar neuropathies at the wrist cases over 14 years. Sport-related ulnar neuropathies at the wrist cases were due to cycling (5 cases), kayaking (2 cases), and big-game fishing (1 case). No patient had sensory complaints in ulnar digits, and all had motor impairment. Conduction across the wrist with recording on the first dorsal interosseous muscle was impaired in all cases, with conduction block in 5. Two cyclists showed bilateral ulnar neuropathies at the wrist. All cases recovered within 2 to 6 months with sport discontinuation. Distal lesions of the deep motor branch were more frequent in sport- than non-sport-related cases. The 8 sport-related ulnar neuropathies at the wrist cases involved the deep motor branch. Conduction study to the first dorsal interosseous muscle across the wrist is the key to electrodiagnostics. Bilateral cases in cyclists does not require wrist imaging. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  15. [Ectopic breast fibroadenoma. Case report].

    Science.gov (United States)

    Senatore, G; Zanotti, S; Cambrini, P; Montroni, I; Pellegrini, A; Montanari, E; Santini, D; Taffurelli, M

    2010-03-01

    Among the rare anomalies of the breast development, polythelia is the most common, between 1% and 5% of women and men present supernumerary nipples. Polymastia, usually presenting as ectopic breast tissue without areola-nipple complex, is seen mostly along the milk line, extending from the axilla to the pubic region. Ectopic breast tissue is functionally analogous to mammary gland and it is subjected to the same alterations and diseases, whether benign or malignant, that affect normal breast tissue. We report the case of a 21 years-old female evaluated by the medical staff after founding a solid nodular mass by suspect axillary lymphadenopathy. Differential diagnosis with lymphoma is the major problem in these cases. The mass was removed and the intraoperative histological examination showed fibroadenoma in axillary supernumerary breast. Presence of ectopic breast tissue is a rare condition; development of benign mass or malignant degeneration is possible, but it is very unusual. In case of polymastia diagnosis is simple; in case of isolated nodule, without local inflammation or infection, there are greater difficulties. Ultrasonography is diagnostic in case of breast fibroadenoma, but it might be inadequate in ectopic localizations owing to the shortage of mammary tissue around the mass. Preoperative diagnosis is important to plan an adequate surgical treatment; lumpectomy is indicated in case of benign tissue; in case of malignancy, therapy is based on the standard treatment used for breast cancer (surgery, chemotherapy and radiation therapy).

  16. Two cases of rheumatoid meningitis.

    Science.gov (United States)

    Magaki, Shino; Chang, Edward; Hammond, Robert R; Yang, Isaac; Mackenzie, Ian R A; Chou, Benedict T; Choi, Soo I; Jen, Joanna C; Pope, Whitney B; Bell, David A; Vinters, Harry V

    2016-02-01

    Central nervous system (CNS) involvement by rheumatoid arthritis (RA) in the form of rheumatoid meningitis (RM) is rare and most commonly occurs in the setting of longstanding severe RA. Due to a wide range of clinical presentations and nonspecific laboratory findings, it presents a diagnostic challenge often requiring brain biopsy. Only a few histopathologically confirmed cases have been described in the literature. Our aim is to describe two cases of RM and review the literature. The first case is of a previously healthy 37-year-old man who presented with severe headaches and focal neurologic deficits. Magnetic resonance imaging demonstrated abnormal leptomeningeal enhancement in the left frontal and parietal sulci. The second case is of a 62-year-old woman with a history of mild chronic joint pain who presented with confusion, personality changes and seizures. Both patients ultimately underwent brain biopsy which demonstrated RM on pathologic examination. Administration of corticosteroids resulted in significant clinical improvement in both cases. To our knowledge, our unusual case of RM in the young man is the fifth reported case of rheumatoid meningitis in a patient with no prior history of RA. Such an atypical presentation makes diagnosis even more difficult and highlights the need for awareness of this entity in the diagnostic consideration of a patient presenting with unexplained neurologic symptoms. Our literature review underscores the clinical and pathologic heterogeneity of CNS involvement in RA. © 2015 Japanese Society of Neuropathology.

  17. Sensitivity analysis for matched pair analysis of binary data: From worst case to average case analysis.

    Science.gov (United States)

    Hasegawa, Raiden; Small, Dylan

    2017-12-01

    In matched observational studies where treatment assignment is not randomized, sensitivity analysis helps investigators determine how sensitive their estimated treatment effect is to some unmeasured confounder. The standard approach calibrates the sensitivity analysis according to the worst case bias in a pair. This approach will result in a conservative sensitivity analysis if the worst case bias does not hold in every pair. In this paper, we show that for binary data, the standard approach can be calibrated in terms of the average bias in a pair rather than worst case bias. When the worst case bias and average bias differ, the average bias interpretation results in a less conservative sensitivity analysis and more power. In many studies, the average case calibration may also carry a more natural interpretation than the worst case calibration and may also allow researchers to incorporate additional data to establish an empirical basis with which to calibrate a sensitivity analysis. We illustrate this with a study of the effects of cellphone use on the incidence of automobile accidents. Finally, we extend the average case calibration to the sensitivity analysis of confidence intervals for attributable effects. © 2017, The International Biometric Society.

  18. Formal Analysis Of Use Case Diagrams

    Directory of Open Access Journals (Sweden)

    Radosław Klimek

    2010-01-01

    Full Text Available Use case diagrams play an important role in modeling with UML. Careful modeling is crucialin obtaining a correct and efficient system architecture. The paper refers to the formalanalysis of the use case diagrams. A formal model of use cases is proposed and its constructionfor typical relationships between use cases is described. Two methods of formal analysis andverification are presented. The first one based on a states’ exploration represents a modelchecking approach. The second one refers to the symbolic reasoning using formal methodsof temporal logic. Simple but representative example of the use case scenario verification isdiscussed.

  19. Gastric pseudolymphoma: Report of 3 cases

    International Nuclear Information System (INIS)

    Lee, Mi Sook; Kim, Ki Whang; Kim, Dong Ik; Lee, Jong Tae; Park, Chang Yun

    1983-01-01

    The pseudolymphoma of the stomach is known to be a benign proliferation of lymphoid tissue, which can be mistaken histologically for malignant lymphoma. The etiology of pseudo lymphoma is controversial, but it B believed to be a manifestation of chronic inflammatory process. Authors present 3 cases of gastric lymphoma. Impression of upper gastrointestinal series were as follows; lymphoma or chronic gastritis in one case, ulcerative carcinoma in another case and early gastric carcinoma in the other case. Initial endoscopic findings suggested infiltrating carcinoma, ulcerative carcinoma and two benign gastric ulcers, respectively. One case was associated with early gastric carcinoma

  20. Gastric pseudolymphoma: Report of 3 cases

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Mi Sook; Kim, Ki Whang; Kim, Dong Ik; Lee, Jong Tae; Park, Chang Yun [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    1983-12-15

    The pseudolymphoma of the stomach is known to be a benign proliferation of lymphoid tissue, which can be mistaken histologically for malignant lymphoma. The etiology of pseudo lymphoma is controversial, but it B believed to be a manifestation of chronic inflammatory process. Authors present 3 cases of gastric lymphoma. Impression of upper gastrointestinal series were as follows; lymphoma or chronic gastritis in one case, ulcerative carcinoma in another case and early gastric carcinoma in the other case. Initial endoscopic findings suggested infiltrating carcinoma, ulcerative carcinoma and two benign gastric ulcers, respectively. One case was associated with early gastric carcinoma.

  1. The input ambiguity hypothesis and case blindness: an account of cross-linguistic and intra-linguistic differences in case errors.

    Science.gov (United States)

    Pelham, Sabra D

    2011-03-01

    English-acquiring children frequently make pronoun case errors, while German-acquiring children rarely do. Nonetheless, German-acquiring children frequently make article case errors. It is proposed that when child-directed speech contains a high percentage of case-ambiguous forms, case errors are common in child language; when percentages are low, case errors are rare. Input to English and German children was analyzed for percentage of case-ambiguous personal pronouns on adult tiers of corpora from 24 English-acquiring and 24 German-acquiring children. Also analyzed for German was the percentage of case-ambiguous articles. Case-ambiguous pronouns averaged 63·3% in English, compared with 7·6% in German. The percentage of case-ambiguous articles in German was 77·0%. These percentages align with the children's errors reported in the literature. It appears children may be sensitive to levels of ambiguity such that low ambiguity may aid error-free acquisition, while high ambiguity may blind children to case distinctions, resulting in errors.

  2. Exceptional mobility of an advancing rhyolitic obsidian flow at Cordón Caulle volcano in Chile.

    Science.gov (United States)

    Tuffen, Hugh; James, Mike R; Castro, Jonathan M; Schipper, C Ian

    2013-01-01

    The emplacement mechanisms of rhyolitic lava flows are enigmatic and, despite high lava viscosities and low inferred effusion rates, can result in remarkably, laterally extensive (>30 km) flow fields. Here we present the first observations of an active, extensive rhyolitic lava flow field from the 2011-2012 eruption at Cordón Caulle, Chile. We combine high-resolution four-dimensional flow front models, created using automated photo reconstruction techniques, with sequential satellite imagery. Late-stage evolution greatly extended the compound lava flow field, with localized extrusion from stalled, ~35 m-thick flow margins creating >80 breakout lobes. In January 2013, flow front advance continued ~3.6 km from the vent, despite detectable lava supply ceasing 6-8 months earlier. This illustrates how efficient thermal insulation by the lava carapace promotes prolonged within-flow horizontal lava transport, boosting the extent of the flow. The unexpected similarities with compound basaltic lava flow fields point towards a unifying model of lava emplacement.

  3. Case Report

    DEFF Research Database (Denmark)

    Søborg, Marie-Louise Kulas; Rosenberg, Jacob; Burcharth, Jakob

    2016-01-01

    Guillain-Barré syndrome (GBS) is an acute ascending peripheral neuropathy, caused by autoimmune damage of the peripheral nerves. GBS can be divided into three subtypes: acute inflammatory demyelinating neuropathy, acute motor axonal neuropathy, and the more rare type, acute motor and sensory axonal...... neuropathy (AMSAN). Reports of AMSAN with onset after epidural anesthesia and spinal surgery are extremely rare, and the linkage between development of GBS and neuroaxial anesthesia remains conclusively unconfirmed. We present a case in which the patient developed subacute motor and predominantly sensory...... neuropathy following epidural blockade. The case emphasizes the need of including AMSAN in differential diagnostic considerations to changes in motor and sensory function following epidural anesthesia, allowing accelerated rehabilitation and relevant alleviating therapy....

  4. Case law

    International Nuclear Information System (INIS)

    2014-01-01

    This section of the Bulletin brings together the texts of the following case laws: Canada: - Judgment of the Federal Court of Canada sending back to a joint review panel for reconsideration the environmental assessment of a proposed new nuclear power plant in Ontario. France : - Conseil d'etat, 24 March 2014 (Request No. 358882); - Conseil d'etat, 24 March 2014 (Request No. 362001). Slovak Republic: - Further developments in cases related to the challenge by Greenpeace Slovakia to the Mochovce nuclear power plant; - Developments in relation to the disclosure of information concerning the Mochovce nuclear power plant. United States: - Initial Decision of the Atomic Safety and Licensing Board Ruling in Favour of Nuclear Innovation North America, LLC (NINA) Regarding Foreign Ownership, Control or Domination

  5. Trichinosis - case presentation

    Directory of Open Access Journals (Sweden)

    Rajko Saletinger

    2007-03-01

    Full Text Available Background: Trichinosis is a widespread zoonosis acquired by ingestion of undercooked meat infected with the larvae of Trichinella parasites. The disease has variable clinical manifestations ranging from asymptomatic to fatal. Majority of infections is caused by Trichinella spiralis, although there are some cases caused by other species. The dramatic decline of trichinosis reflects changes in industrial practices and increased public awareness. The majority of human cases are now associated with wild game meat and noncommercial pork. The case of previously healthy, young man with trichinosis is presented. The disease was determined with serologic testing and cured with albendazole. The source of infection has not been determined.Conclusions: In patients with fever, mialgias and eosinophilia infection with tissue nematodes should always be taken in consideration. In those who have recently consumed raw or undercooked pork and wild game meat we should think about trichinosis. The disease is rare in Slovenia.

  6. Cytological diagnosis of erythema nodosum leprosum in clinically unsuspected cases: A report of two cases

    Directory of Open Access Journals (Sweden)

    Shruti Semwal

    2018-01-01

    Full Text Available Leprosy is a chronic infectious disease caused by Mycobacterium leprae. The manifestations of this disease varies across the spectrum of tuberculoid (TT to lepromatous (LL leprosy.The course of this indolent disease is interrupted by acute exacerbations in the form of leprare actions. Erythema nodosum leprosum (ENL, a type 2 lepra reaction, occurs in lepromatous or borderline lepromatous cases, usually in response to multidrug therapy. Early detection and timely management of these patients is important to reduce the associated morbidity. We report two clinically unusual cases of ENL on fine-needle aspiration cytology. In one case, antileprosy treatment was completed 10 years back, whereas in the other case, ENL was the presenting feature of the disease. Cytological examination of swelling in both the cases showed neutrophils, lymphoid cells, clusters of foamy macrophages, histiocytes, and giant cells. Fite stain was positive, which confirmed the cytological diagnosis of ENL.

  7. Deregulation impacts AMR business cases

    Energy Technology Data Exchange (ETDEWEB)

    Wiebe, M.; Fauth, G.

    2001-09-01

    Meter reading strategy is being affected in fundamental ways by deregulation. For the utilities attempting to cope with meter reading unbundling, the processes, insights and general rules that had been developed prior to 2000 in the field of Automatic Meter Reading can no longer be relied upon to provide useful lessons. The fundamental impact on Automatic Meter Reading (AMR) business case drivers and the increasing complexity of building the business case model result from deregulation and unbundling. More and more, management has come to rely on rigorous business case analysis to compensate for the magnitude of AMR projects on the utility and the scarcity of financial resources. One can now expect the Chief Financial Officer and the Vice President Finance to become active players on AMR project teams in the fields of business case scrutiny and approval. Increasingly, the normal expertise of AMR personnel does not suffice to build a business case acceptable to finance. The financial and economic analysis skills required are ever more complex.

  8. Intrahepatic splenosis: a case report

    International Nuclear Information System (INIS)

    Pekkafali, Zekai; Karsli, Fevzi A.; Silit, Emir; Basekim, Cinar C.; Mutlu, Hakan; Kizilkaya, Esref; Narin, Yavuz

    2002-01-01

    Splenosis is heterotopic autotransplantation and seeding of splenic tissue. In the literature, only a few cases of splenosis involving the liver and the radiologic characteristics of these lesions have been reported. We report a case of intrahepatic splenosis diagnosed by ultrasound, computed tomography, magnetic resonance imaging and scintigraphic features. To our knowledge, our patient is the first case diagnosed only by radiologic and radionuclide examination without any intervention. (orig.)

  9. Pathomorphological study on 106 autopsy cases of Thorotrast-related hepatic malignancies with comparison to non-Thorotrast-related cases

    International Nuclear Information System (INIS)

    Kojiro, Masamichi; Ito, Yuji

    1989-01-01

    The pathomorphological features of 106 autopsy cases of Thorotrast-related malignant tumours of the liver were studied and compared to those of non-Thorotrast-related cases. Among the 106 cases, 44 (41.5%) were cholangiocarcinoma, 42 (39.6%) were angiosarcoma, 17 (16.0%) were hepatocellular carcinoma, and three (2.8%) were double cancers. In contrast, in non-Thorotrast-related cases about 90% of the cases were hepatocellular and angiosarcoma was extremely rare. (author)

  10. Case report 363

    International Nuclear Information System (INIS)

    Langer, R.; Kaufmann, H.J.

    1986-01-01

    In summary, the case is presented of a 10-year-old girl with a fibrosarcoma of the femoral shaft, which showed the radiological and histological features of a malignant bone tumor, but with no findings radiologically pathognomonic of fibrosarcoma. Malignant fibrous histiocytoma, fibrogenic osteosarcoma and even Ewing tumor could present with the same radiological features. Although permeative infiltration of bone (described in this case) is observed in primary fibrosarcoma, it is much more commonly associated with another malignant bone tumor of childhood - Ewing tumor. (orig./SHA)

  11. Case Report

    African Journals Online (AJOL)

    of permanent hemodialysis (HD) vascular access ... This catheter was removed and a translumbar dialysis ... In this case report, we describe a patient with the ... Rheumatology, the isolated detection of antiphospholipid .... Arthritis Rheum.

  12. Case report

    African Journals Online (AJOL)

    ebutamanya

    2015-01-06

    Jan 6, 2015 ... optic disc edema and subsequent formation of a macular star [1]. (Figure 1). ... case of bilateral stellate neuroretinitis due to pheochromocytoma. ... clinical examination are irreplaceable, powerful diagnostic tools that.

  13. Vascular colitis: a report of two cases

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan Il; Han, Chang Yul; Han, Man Chung; Choo, Dong Woon [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1973-04-15

    The authors report two cases of vascular colitis in Korean with a review of literature. Case I, 20 years old male had severe abdominal pain and bloody diarrhea. Case II was 57 years old male and complained severe abdominal pain. Barium enema colon study on each cases disclosed typical thumbprinting appearance of involved segment. Predisposing factor in case I appeared to be anaphylactoid purpura, and in case II distal obstruction due to adenocarcinoma. The mechanism of vascular was briefly discussed.

  14. Eleven cases of neonatal intracranial hemorrhage

    International Nuclear Information System (INIS)

    Matsuda, Tadashi; Asao, Toyohiko; Shibata, Takeo

    1981-01-01

    Eleven cases of neonatal intracranial hemorrhage were diagnosed and followed up by CT scanning. By CT, hemorrhagic lesions were shown as high density areas in an acute stage and imaged as low density areas after the hemorrhage was absorbed. The time of absorption varies depending upon the site and the severity of hemorrhage. Intraventricular hemorrhage, petechial hemorrhage and subdural hematoma were absorbed rapidly in more than 70% of the exanimed cases, CT scanning 1 - 2 weeks after the onset revealed absorption of hemorrhage. However, the absorption delayed in intracerebral hematoma; CT scan taken after one month showed hemorrhagic lesions remaining in 75% of the cases. In nine cases who survived, following the absorption of the hemorrhagic lesions, cerebral atrophy was observed in 4 cases (44%), ventricular enlargement in 3 cases (33%), and complete recovery in 2 cases (22%). From these results, CT scanning for diagnosis of neonatal intracranial hemorrhage should be done before the hemorrhagic lesion is absorbed (within 7 days of the onset). Follow-up study by CT is important for observing changes and predicting prognosis of intracranial hemorrhage. (Ueda, J.)

  15. ASRM case insulation design and development

    Science.gov (United States)

    Bell, Matthew S.; Tam, William F. S.

    1992-10-01

    This paper describes the achievements made on the Advanced Solid Rocket Motor (ASRM) case insulation design and development program. The ASRM case insulation system described herein protects the metal case and joints from direct radiation and hot gas impingement. Critical failure of solid rocket systems is often traceable to failure of the insulation design. The wide ranging accomplishments included the development of a nonasbestos insulation material for ASRM that replaced the existing Redesigned Solid Rocket Motor (RSRM) asbestos-filled nitrile butadiene rubber (NBR) along with a performance gain of 300 pounds, and improved reliability of all the insulation joint designs, i.e., segmented case joint, case-to-nozzle and case-to-igniter joint. The insulation process development program included the internal stripwinding process. This process advancement allowed Aerojet to match to exceed the capability of other propulsion companies.

  16. Teaching Case: Enterprise Architecture Specification Case Study

    Science.gov (United States)

    Steenkamp, Annette Lerine; Alawdah, Amal; Almasri, Osama; Gai, Keke; Khattab, Nidal; Swaby, Carval; Abaas, Ramy

    2013-01-01

    A graduate course in enterprise architecture had a team project component in which a real-world business case, provided by an industry sponsor, formed the basis of the project charter and the architecture statement of work. The paper aims to share the team project experience on developing the architecture specifications based on the business case…

  17. Marketing communication plan. Case: EKOenergy.

    OpenAIRE

    Jäkälä, Elina

    2016-01-01

    This project-based thesis has an objective of creating a marketing communication plan for a non-profit organisation. The marketing communication plan targets other non-profit organisa-tions that the case organisation wants to cooperate with. This thesis will introduce theory about marketing communication, give information about the case organisation’s target audience and present the actual marketing communication plan. Since the case organisation and its target audience are all non-profit...

  18. Trichotillomania in a dementia case

    OpenAIRE

    Caixeta, Leonardo; Lopes, Danielly Bandeira

    2011-01-01

    Abstract We report an 87-year-old male case of hair pulling associated with a white-matter vascular dementia (Binswanger's disease). Trichotillomania in our case did not resolve using mirtazapine or anticholinesterasic medication. Trichotillomania seems to be related to a form of perseveration associated with dementia. The findings in this case suggest the abnormality involving white matter in the pathogenesis of trichotillomania, may constitute a defect in connectivity in the right frontal-s...

  19. Pathomorphological study on 106 autopsy cases of Thorotrast-related hepatic malignancies with comparison to non-Thorotrast-related cases

    International Nuclear Information System (INIS)

    Kojiro, Masamichi; Ito, Yuji

    1989-01-01

    The pathomorphological features of 106 autopsy case of Thorotrast (TH)-related malignant tumours of the liver were studied and compared to those of non-Thorotrast-related cases. Among the 106 cases, 44 (41.5%) were cholangiocarcinoma (CHC), 42(39.6%) were angiosarcoma (AGS), 17(16.0%) were hepatocellular carcinoma (HCC), and three (2.8%) were double cancers. In contrast, in non-Thorotrast-related cases about 90% of the cases were hepatocellular and angiosarcoma was extremely rare. (author)

  20. Vitamin B6 in Health Supplements and Neuropathy: Case Series Assessment of Spontaneously Reported Cases.

    Science.gov (United States)

    van Hunsel, Florence; van de Koppel, Sonja; van Puijenbroek, Eugène; Kant, Agnes

    2018-05-08

    In the literature, vitamin B 6 has been linked to the development of polyneuropathy. Most often, these complaints were seen when taking high doses of vitamin B 6 for a long time. Evidence as to whether a lower dosage range of vitamin B 6 (< 50 mg/day) can also induce neuropathy is scarce. We aim to comprehensively describe the cases of neuropathy associated with vitamin B 6 received by the Netherlands Pharmacovigilance Centre Lareb and to assess the case series concerning the use of vitamin B 6 and neuropathic complaints. We describe the number and nature of the reported cases, including suspect product, dosage, duration of use, and vitamin B 6 serum levels. In addition, we describe the causality for the individual cases (Naranjo Probability Scale) and for the entire case series (Bradford Hill criteria). In total, 90 reports on products containing vitamin B 6 included at least one adverse drug reaction in the standardized Medical Dictionary for Regulatory Activities (MedDRA ® ) query (SMQ; broad) 'peripheral neuropathy'. The amount of vitamin B 6 in the products varied between 1.4 and 100 mg per tablet. The serum vitamin B 6 level was known in 36 cases (88-4338 nmol/l), and the mean serum vitamin B 6 level was 907 nmol/l. However, no statistical correlation between dosage and vitamin B 6 blood levels was found. Causality assessment of the case series of 90 reports to Lareb shows it is plausible for the vitamin B 6 supplements to have caused complaints such as neuropathies. This is especially the case with higher dosages and prolonged use, but dosages < 50 mg/day also cannot be excluded.

  1. The CASE Project: Evaluation of Case-Based Approaches to Learning and Teaching in Statistics Service Courses

    Science.gov (United States)

    Fawcett, Lee

    2017-01-01

    The CASE project (Case-based Approaches to Statistics Education; see www.mas.ncl.ac.uk/~nlf8/innovation) was established to investigate how the use of real-life, discipline-specific case study material in Statistics service courses could improve student engagement, motivation, and confidence. Ultimately, the project aims to promote deep learning…

  2. A case of pancreatolithiasis

    International Nuclear Information System (INIS)

    Sasaki, Fumio; Koga, Sukehiko; Takeuchi, Akira

    1982-01-01

    During 3-year follow-up of a case of pancreatolithiasis localized in the pancreatic head, CT showed sudden new appearance of calculi over an extensive area of the body and tail of the pancreas after acute exacerbation of chronic pancreatitis. This case and the etiology and mechanism of pancreatolithiasis were discussed on the basis of literature. (Chiba, N.)

  3. Aims and harvest of moral case deliberation.

    Science.gov (United States)

    Weidema, Froukje C; Molewijk, Bert A C; Kamsteeg, Frans; Widdershoven, Guy A M

    2013-09-01

    Deliberative ways of dealing with ethical issues in health care are expanding. Moral case deliberation is an example, providing group-wise, structured reflection on dilemmas from practice. Although moral case deliberation is well described in literature, aims and results of moral case deliberation sessions are unknown. This research shows (a) why managers introduce moral case deliberation and (b) what moral case deliberation participants experience as moral case deliberation results. A responsive evaluation was conducted, explicating moral case deliberation experiences by analysing aims (N = 78) and harvest (N = 255). A naturalistic data collection included interviews with managers and evaluation questionnaires of moral case deliberation participants (nurses). From the analysis, moral case deliberation appeals for cooperation, team bonding, critical attitude towards routines and nurses' empowerment. Differences are that managers aim to foster identity of the nursing profession, whereas nurses emphasize learning processes and understanding perspectives. We conclude that moral case deliberation influences team cooperation that cannot be controlled with traditional management tools, but requires time and dialogue. Exchanging aims and harvest between manager and team could result in co-creating (moral) practice in which improvements for daily cooperation result from bringing together perspectives of managers and team members.

  4. [Research and control of relapse tuberculosis cases].

    Science.gov (United States)

    Yamagishi, Fumio; Toyota, Makoto

    2009-12-01

    With this symposium, we focused on the relapse of tuberculosis in Japan. Out of 19,893 tuberculosis patients registered in 2007 in Japan, 7.48% were classified as relapse cases. Relapse cases have the risk of acquired drug resistance. But we have few analyses of the proportion of relapse tuberculosis cases with standard short course regimens for six months, factors contributing to tuberculosis relapse and the proportion of drug resistance among relapse TB cases in Japan. Therefore we analyzed the relapse tuberculosis cases in two rural areas and three urban areas. We also analyzed the proportion of drug resistance among relapse cases with the data of drug susceptibility survey of Ryoken. 1. Research of relapse tuberculosis cases: Makoto TOYOTA (Kochi City Public Health Center). To clarify the relapse rate and factors contributing to tuberculosis relapse, we investigated the relapse tuberculosis cases in the municipality where the proportion of elderly tuberculosis patients was high. Out of 902 tuberculosis patients registered in Kochi City Public Health Center during 10 years, 20 pulmonary tuberculosis patients were confirmed relapse cases with initial registered records. Pretreatment cavitations, sputum culture positivity at 2 months, medical miss-management (e.g. number of doses, duration of therapy) and poor adherence were considered to be factors contributing to tuberculosis relapse. Out of 20 relapse cases, 12 cases were detected with symptoms, while only 3 cases were detected by examination in law. 2. A clinical study on relapse cases of pulmonary tuberculosis: Shuichi TAKIKAWA (National Hospital Organization Nishibeppu National Hospital). The relapse of pulmonary tuberculosis was investigated. In the cases with a treatment history before short course chemotherapy, drug resistance rate was high, and thus it needs to be cautious of drug resistance at the time of the retreatment. In the cases with a treatment history of short course chemotherapy, relapse cases

  5. Case report

    African Journals Online (AJOL)

    abp

    2017-10-10

    Oct 10, 2017 ... A rare case of important and recurrent abnormal uterine bleeding ... 1Department of Obstetrics and Gynecology, University Hospital of Yopougon, Abidjan, Ivory Coast, .... imaging (MRI) could guide us to the diagnosis.

  6. Case Report

    African Journals Online (AJOL)

    Hamid

    Key words: Case report, composite resin, fiber-reinforced composite. ABSTRACT. A variety of ... investigation will be required to provide additional information on the survival of directly-bonded anterior fixed prosthesis made with FRC systems.

  7. Dermatology case

    Directory of Open Access Journals (Sweden)

    Fernando Mota

    2017-07-01

    In the present case, the patient was referred to the dermatology department due to an atypical lesion with an uncommon location, revealing the importance of a whole body examination in patients with this disease.

  8. Case report

    African Journals Online (AJOL)

    ebutamanya

    2015-10-14

    Oct 14, 2015 ... &Corresponding author: Hanane Massit, Department of Gastroenterology II, Mohamed V ... Crohn's disease, accounting for around 30-50 % of cases, its ... manuscript and have equally contributed to its content and to the.

  9. Case series

    African Journals Online (AJOL)

    abp

    2017-05-16

    May 16, 2017 ... Hepatocellular carcinoma: a clinicopathological study of 64 cases ... The presenting clinical symptoms were dominated by abdominal pain (n=34), followed by .... malaise, anorexia or weight loss and nausea or vomiting [4].

  10. Case report

    African Journals Online (AJOL)

    abp

    2017-11-07

    Nov 7, 2017 ... However, auricular disorders are rare and exceptionally inaugural. We describe the case of ... hypothalamic-pituitary axis dysfonction. There was ... tomography, and the salivary gland biopsy confirmed the diagnosis by finding ...

  11. Case report

    African Journals Online (AJOL)

    ebutamanya

    2015-03-03

    translucent, hyper-or hypopigmented or erythematous-to- violaceous in color. In addition, epidermal changes may be absent or include atrophy, hyperkeratosis, or telangiectasia [2]. In our case the diagnosis of cutaneous sarcoidosis is ...

  12. Prosthetic rehabilitation of oral submucous fibrosis patients: A systematic review of published case reports and case series.

    Directory of Open Access Journals (Sweden)

    Shankargouda Patil

    Full Text Available Oral submucous fibrosis (OSF is an insidious chronic condition characterized by restricted mouth opening. Prosthetic rehabilitation is challenging for OSF patients as obtaining a good impression requires adequate mouth opening. The aim of the present review is to systematically present the data from case reports published in the English-language literature.A comprehensive search of the literature databases (PubMed, Medline, SCOPUS, Web of Science and Google Scholar along with the references of published articles on prosthetic rehabilitation in OSF patients published to date was conducted. Keywords included a combination of 'Oral submucous fibrosis', 'prosthesis', 'dentures' and/or 'restricted mouth opening'. Citations from selected references and bibliographic linkages taken from similar cases were included in this review. The inclusion criteria selected for case reports on prosthetic rehabilitation in OSF patients, and cases of restricted mouth opening due to causes other than OSF were excluded from the study.A total of 21 cases were identified and analysed from 17 papers published in the English-language literature. Of these, 9 cases employed the sectional denture technique, 4 cases emphasized the need-based treatment approach in which conventional methods were modified, and 4 cases used mouth exercising devices. Finally, 1 case each involved, flexible denture, oral screen prosthesis, oral stents, surgery in conjunction with dentures.Prosthetic rehabilitation in OSF patients is a multifaceted approach and should be patient specific, although sectional dentures have achieved the best results.

  13. Prosthetic rehabilitation of oral submucous fibrosis patients: A systematic review of published case reports and case series.

    Science.gov (United States)

    Patil, Shankargouda; Sarode, Sachin Chakradhar; Sarode, Gargi S; Bhandi, Shilpa; Awan, Kamran Habib; Ferrari, Marco

    2017-01-01

    Oral submucous fibrosis (OSF) is an insidious chronic condition characterized by restricted mouth opening. Prosthetic rehabilitation is challenging for OSF patients as obtaining a good impression requires adequate mouth opening. The aim of the present review is to systematically present the data from case reports published in the English-language literature. A comprehensive search of the literature databases (PubMed, Medline, SCOPUS, Web of Science and Google Scholar) along with the references of published articles on prosthetic rehabilitation in OSF patients published to date was conducted. Keywords included a combination of 'Oral submucous fibrosis', 'prosthesis', 'dentures' and/or 'restricted mouth opening'. Citations from selected references and bibliographic linkages taken from similar cases were included in this review. The inclusion criteria selected for case reports on prosthetic rehabilitation in OSF patients, and cases of restricted mouth opening due to causes other than OSF were excluded from the study. A total of 21 cases were identified and analysed from 17 papers published in the English-language literature. Of these, 9 cases employed the sectional denture technique, 4 cases emphasized the need-based treatment approach in which conventional methods were modified, and 4 cases used mouth exercising devices. Finally, 1 case each involved, flexible denture, oral screen prosthesis, oral stents, surgery in conjunction with dentures. Prosthetic rehabilitation in OSF patients is a multifaceted approach and should be patient specific, although sectional dentures have achieved the best results.

  14. TA Treatment of Depression - A Hermeneutic Single-Case Efficacy Design Study - ‘Linda’ - a mixed outcome case

    Directory of Open Access Journals (Sweden)

    Mark Widdowson

    2013-07-01

    Full Text Available Hermeneutic Single-Case EfficacyDesign (HSCED is a systematic case study research method involving the cross-examination of mixed method data to generate both plausible arguments that the client changed due to therapy and alternative explanations. The present study is the fourth article of a case series which has investigated the process and outcome of transactional analysis psychotherapy using Hermeneutic Single-Case Efficacy Design (Elliott 2002. The client, Linda, was a 45 yearold white British woman with mild depression who attended nine sessions of therapy. The conclusion of the judges was that this was a mixed-outcome case:whilst the client improved over the course of therapy and was positive about her experience of therapy, her changes did not last when she experienced considerable stressful events during follow-up. Linda provided a detailed and idiosyncratic description of the aspects of the therapy which were most helpful for her. A cross-case comparison with other cases in this series suggests several interesting features which are worthy of further investigation. Specifically, the use of a shared theoretical framework and an egalitarian therapeutic relationship were helpful. As with other cases in this series, the client experienced positive changes in her interpersonal relationships suggesting that this outcome of TA therapy warrants further investigation

  15. Writing a case report: polishing a gem?

    Science.gov (United States)

    Papanas, N; Lazarides, M K

    2008-08-01

    Case reports describe patient cases which are of particular interest due to their novelty and their potential message for clinical practice. While there are several types of case reports, originality and clinical implications constitute the main virtues by which case reports are judged. Defining the educational message and choosing the right audience are vital steps in the process of writing. Generally, a case report is structured, its main components being the abstract, the introduction, the case description and the discussion. Guidelines and tips for writing case reports are not enough for making a successful author, but they help, especially less experienced doctors, to exercise and improve their writing. If properly prepared, case reports can still communicate new observations in an interesting and pleasant way, thereby enriching our knowledge, even in the era of evidence-based medicine.

  16. [Research and development of medical case database: a novel medical case information system integrating with biospecimen management].

    Science.gov (United States)

    Pan, Shiyang; Mu, Yuan; Wang, Hong; Wang, Tong; Huang, Peijun; Ma, Jianfeng; Jiang, Li; Zhang, Jie; Gu, Bing; Yi, Lujiang

    2010-04-01

    To meet the needs of management of medical case information and biospecimen simultaneously, we developed a novel medical case information system integrating with biospecimen management. The database established by MS SQL Server 2000 covered, basic information, clinical diagnosis, imaging diagnosis, pathological diagnosis and clinical treatment of patient; physicochemical property, inventory management and laboratory analysis of biospecimen; users log and data maintenance. The client application developed by Visual C++ 6.0 was used to implement medical case and biospecimen management, which was based on Client/Server model. This system can perform input, browse, inquest, summary of case and related biospecimen information, and can automatically synthesize case-records based on the database. Management of not only a long-term follow-up on individual, but also of grouped cases organized according to the aim of research can be achieved by the system. This system can improve the efficiency and quality of clinical researches while biospecimens are used coordinately. It realizes synthesized and dynamic management of medical case and biospecimen, which may be considered as a new management platform.

  17. Casing and liners for drilling and completion

    CERN Document Server

    Byrom, Ted G

    2007-01-01

    The Gulf Drilling Series is a joint project between Gulf Publishing Company and the International Association of Drilling Contractors. The first text in this Series presents casing design and mechanics in a concise, two-part format. The first part focuses on basic casing design and instructs engineers and engineering students how to design a safe casing string. The second part covers more advanced material and special problems in casing design in a user-friendly format. Learn how to select sizes and setting depths to achieve well objectives, determine casing loads for design purposes, design casing properties to meet burst, collapse and tensile strength requirements and conduct casing running operations safely and successfully.

  18. Case law

    International Nuclear Information System (INIS)

    Anon.

    2011-01-01

    This chapter gathers three case laws, one concerning France and the two others concerning the United States. France - Decision of the Administrative Court in Strasbourg on the permanent shutdown of the Fessenheim nuclear power plant: On 9 March 2011, the administrative court in Strasbourg confirmed the government's rejection to immediately close the Fessenheim nuclear power plant, the first unit of which started operation on 1 January 1978. The court rejected the motion of the 'Association trinationale de protection nucleaire' (ATPN) filed against the decision of the Minister of Economy, Industry and Employment to refuse the final shutdown of the plant. The group, which brings together associations as well as French, German and Swiss municipalities, had taken legal action in December 2008. United States - Case law 1 - Judgment of a US Court of Appeals on public access to sensitive security information and consideration of the environmental impacts of terrorist attacks on nuclear facilities: This case concerns 1) the public's right to access classified and sensitive security information relied upon by the US Nuclear Regulatory Commission (NRC) in its environmental review; and 2) the sufficiency of the NRC's environmental review of the impacts of terrorist attacks for a proposed Independent Spent Fuel Storage Installation (ISFSI). In 2003, the NRC ruled that the National Environmental Policy Act (NEPA) did not require the NRC to consider the impacts of terrorist attacks in its environmental review for the proposed ISFSI at the Diablo Canyon Power Plant. ' NEPA mandates that all federal agencies must prepare a detailed statement on the environment impacts before undertaking a major federal action that significantly affects the human environment. In 2004, the San Luis Obispo Mothers for Peace, a group of individuals who live near the Diablo Canyon Power Plant, filed a petition in the US Court of Appeals for the Ninth Circuit challenging the NRC's 2003 decision. The

  19. Trichotillomania in a dementia case

    Directory of Open Access Journals (Sweden)

    Leonardo Caixeta

    Full Text Available Abstract We report an 87-year-old male case of hair pulling associated with a white-matter vascular dementia (Binswanger's disease. Trichotillomania in our case did not resolve using mirtazapine or anticholinesterasic medication. Trichotillomania seems to be related to a form of perseveration associated with dementia. The findings in this case suggest the abnormality involving white matter in the pathogenesis of trichotillomania, may constitute a defect in connectivity in the right frontal-subcortical circuit.

  20. Rhabdomyolysis case based on hypothyroidism

    OpenAIRE

    Bilal Katipoglu; Ihsan Ates; Fatih Acehan; Ayşenur Meteris; Nisbet Yılmaz

    2016-01-01

    Summary Hypothyroidism is a wide clinical spectrum disorder and only a few cases in literature show this. Rhabdomyolysis and acute renal impairment can be seen concurrently in a hypothyroid state. We report a case of severe hypothyroidism with poor drug compliance leading to rhabdomyolysis and acute kidney injury. Learning points: Hypothyroidism is a rare cause of acute kidney injury. In this case report, we studied a rare occurrence of acute renal impairment due to hypothyroidism with poor d...