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Sample records for eha-mai graf maarja

  1. Max Graf's "Reminiscences of Professor Sigmund Freud" revisited: new evidence from the Freud archives.

    PubMed

    Wakefield, Jerome C

    2007-01-01

    Recently derestricted Freud Archive interviews with Max and Herbert Graf and Herbert's wife shed new light on Max Graf's article, "Reminiscences of Professor Sigmund Freud," published in The Psychoanalytic Quarterly in 1942. To explain discrepancies between the interviews and the earlier article, the author postulates that, in the article, Max Graf purposely distorted or omitted certain details in order not to reveal Herbert's identity as "Little Hans" (Freud 1909). The interviews place incidents reported in the article in a new and more complex light, and also underscore the intensely personal nature of the intellectual development of the psychoanalytic movement.

  2. Vitre-graf Coating on Mullite. Low Cost Silicon Array Project: Large Area Sillicon Sheet Task

    NASA Technical Reports Server (NTRS)

    Rossi, R. C.

    1979-01-01

    The processing parameters of the Vitre-Graf coating for optimal performance and economy when applied to mullite and graphite as substrates were presented. A minor effort was also performed on slip-cast fused silica substractes.

  3. GRAF1a is a brain-specific protein that promotes lipid droplet clustering and growth, and is enriched at lipid droplet junctions

    PubMed Central

    Lucken-Ardjomande Häsler, Safa; Vallis, Yvonne; Jolin, Helen E.; McKenzie, Andrew N.; McMahon, Harvey T.

    2014-01-01

    ABSTRACT Lipid droplets are found in all cell types. Normally present at low levels in the brain, they accumulate in tumours and are associated with neurodegenerative diseases. However, little is known about the mechanisms controlling their homeostasis in the brain. We found that GRAF1a, the longest GRAF1 isoform (GRAF1 is also known as ARHGAP26), was enriched in the brains of neonates. Endogenous GRAF1a was found on lipid droplets in oleic-acid-fed primary glial cells. Exclusive localization required a GRAF1a-specific hydrophobic segment and two membrane-binding regions, a BAR and a PH domain. Overexpression of GRAF1a promoted lipid droplet clustering, inhibited droplet mobility and severely perturbed lipolysis following the chase of cells overloaded with fatty acids. Under these conditions, GRAF1a concentrated at the interface between lipid droplets. Although GRAF1-knockout mice did not show any gross abnormal phenotype, the total lipid droplet volume that accumulated in GRAF1−/− primary glia upon incubation with fatty acids was reduced compared to GRAF1+/+ cells. These results provide additional insights into the mechanisms contributing to lipid droplet growth in non-adipocyte cells, and suggest that proteins with membrane sculpting BAR domains play a role in droplet homeostasis. PMID:25189622

  4. Endocytic membrane turnover at the leading edge is driven by a transient interaction between Cdc42 and GRAF1

    PubMed Central

    Francis, Monika K.; Holst, Mikkel R.; Vidal-Quadras, Maite; Henriksson, Sara; Santarella-Mellwig, Rachel; Sandblad, Linda; Lundmark, Richard

    2015-01-01

    ABSTRACT Changes in cell morphology require coordination of plasma membrane turnover and cytoskeleton dynamics, processes that are regulated by Rho GTPases. Here, we describe how a direct interaction between the Rho GTPase Cdc42 and the GTPase-activating protein (GAP) GRAF1 (also known as ARHGAP26), facilitates rapid cell surface turnover at the leading edge. Both Cdc42 and GRAF1 were required for fluid-phase uptake and regulated the generation of transient GRAF1-coated endocytic carriers, which were distinct from clathrin-coated vesicles. GRAF1 was found to transiently assemble at discrete Cdc42-enriched punctae at the plasma membrane, resulting in a corresponding decrease in the microdomain association of Cdc42. However, Cdc42 captured in its active state was, through a GAP-domain-mediated interaction, localised together with GRAF1 on accumulated internal structures derived from the cell surface. Correlative fluorescence and electron tomography microscopy revealed that these structures were clusters of small membrane carriers with defective endosomal processing. We conclude that a transient interaction between Cdc42 and GRAF1 drives endocytic turnover and controls the transition essential for endosomal maturation of plasma membrane internalised by this mechanism. PMID:26446261

  5. The smooth muscle-selective RhoGAP GRAF3 is a critical regulator of vascular tone and hypertension

    PubMed Central

    Bai, Xue; Lenhart, Kaitlin C.; Bird, Kim E.; Suen, Alisa A.; Rojas, Mauricio; Kakoki, Masao; Li, Feng; Smithies, Oliver; Mack, Christopher P.; Taylor, Joan M.

    2014-01-01

    Although hypertension is a worldwide health issue, an incomplete understanding of its etiology has hindered our ability to treat this complex disease. Here we identify arhgap42 (also known as GRAF3) as a Rho-specific GAP expressed specifically in smooth muscle cells in mice and humans. We show that GRAF3-deficient mice exhibit significant hypertension and increased pressor responses to angiotensin II and endothelin-1; these effects are prevented by treatment with the Rho-kinase inhibitor, Y-27632. RhoA activity and myosin light chain phosphorylation are elevated in GRAF3-depleted smooth muscle cells in vitro and in vivo, and isolated vessel segments from GRAF3-deficient mice show increased contractility. Taken together our data indicate that GRAF3-mediated inhibition of RhoA activity in vascular smooth muscle cells is necessary for maintaining normal blood pressure homeostasis. Moreover, these findings provide a potential mechanism for a hypertensive locus recently identified within arhgap42 and provide a foundation for the future development of innovative hypertension therapies. PMID:24335996

  6. The large area high resolution gamma ray astrophysics facility - HR-GRAF

    NASA Astrophysics Data System (ADS)

    Fenyves, E. J.; Chaney, R. C.; Hoffman, J. H.; Cline, D. B.; Atac, M.; Park, J.; White, S. R.; Zych, A. D.; Tumer, Q. T.; Hughes, E. B.

    1990-03-01

    The long-term program is described in terms of its equipment, scientific objectives, and long-range scientific studies. A prototype of a space-based large-area high-resolution gamma-ray facility (HR-GRAF) is being developed to examine pointlike and diffuse gamma-ray sources in the range 1 MeV-100 GeV. The instrument for the facility is proposed to have high angular and energy resolution and very high sensitivity to permit the study of the proposed objects. The primary research targets include the mapping of galactic gamma radiation, observing the angular variations of diffuse gamma rays, and studying the Galactic center with particular emphasis on the hypothetical black hole. Also included in the research plans are obtaining data on gamma-ray bursters, investigating the transmission of gamma rays from cold dark matter, and studying nuclear gamma-ray lines.

  7. Application of the mathematical Graf's addition theorem to the problem of electron energy absorption in laser-irradiated plasma

    NASA Astrophysics Data System (ADS)

    Krainov, V. P.

    2013-03-01

    The electron energy absorption in laser-irradiated plasma is determined by the sum of the rates of photon absorption and emission. These rates contain the square of the Bessel functions. It was shown that in a moderate laser field, terms with absorption and emission of several photons are large, but cancel exactly each other. Therefore, we should take into account terms with the absorption and emission of only one laser photon. This statement is proved analytically using Graf's theorem for Bessel functions.

  8. The first aeromagnetic survey in the Arctic: results of the Graf Zeppelin airship flight of 1931

    NASA Astrophysics Data System (ADS)

    Raspopov, O. M.; Sokolov, S. N.; Demina, I. M.; Pellinen, R.; Petrova, A. A.

    2013-03-01

    In July of 1931, on the eve of International Polar Year II, an Arctic flight of the Graf Zeppelin rigid airship was organized. This flight was a realization of the idea of F. Nansen, who advocated the use of airships for the scientific exploration of the Arctic territories, which were poorly studied and hardly accessible at that time. The route of the airship flight was Berlin - Leningrad - Arkhangelsk - Franz Josef Land - Severnaya Zemlya - the Taimyr Peninsula - Novaya Zemlya - Arkhangelsk - Berlin. One of scientific goals of the expedition was to measure the H and D geomagnetic field components. Actually, the first aeromagnetic survey was carried out in the Arctic during the flight. After the expedition, only preliminary results of the geomagnetic measurements, in which an anomalous behavior of magnetic declination in the high-latitude part of the route was noted, were published. Our paper is concerned with the first aeromagnetic measurements in the Arctic and their analysis based on archival and modern data on the magnetic field in the Barents and Kara sea regions. It is shown that the magnetic field along the flight route had a complicated structure, which was not reflected in the magnetic charts of those times. The flight was very important for future development of aero- and ground-based magnetic surveys in the Arctic, showing new methods in such surveys.

  9. The human GRAF gene is fused to MLL in a unique t(5;11)(q31;q23) and both alleles are disrupted in three cases of myelodysplastic syndrome/acute myeloid leukemia with a deletion 5q

    PubMed Central

    Borkhardt, Arndt; Bojesen, Stig; Haas, Oskar A.; Fuchs, Uta; Bartelheimer, Dominique; Loncarevic, Ivan F.; Bohle, Rainer M.; Harbott, Jochen; Repp, Reinald; Jaeger, Ulrich; Viehmann, Susanne; Henn, Traudl; Korth, Petra; Scharr, Dirk; Lampert, Fritz

    2000-01-01

    We have isolated the human GRAF gene (for GTPase regulator associated with the focal adhesion kinase pp125FAK). This gene was fused with MLL in a unique t(5;11)(q31;q23) that occurred in an infant with juvenile myelomonocytic leukemia. GRAF encodes a member of the Rho family of the GTPase-activating protein (GAP) family. On the protein level, it is 90% homologous to the recently described chicken GRAF gene that functions as a GAP of RhoA in vivo and is thus a critical component of the integrin signaling transduction pathway. The particular position of the human GRAF gene at 5q31 and the proposed antiproliferative and tumor suppressor properties of its avian homologue suggest that it also might be pathogenetically relevant for hematologic malignancies with deletions of 5q. To investigate this possibility, we sequenced 4–5 individual cDNA clones from 13 cases in which one allele of GRAF was deleted. We found point mutations within the GAP domain of the second GRAF allele in one patient. In two additional patients we found an insertion of 52 or 74 bp within the GRAF cDNA that generates a reading frame shift followed by a premature stop codon. GRAF maps outside the previously defined commonly deleted 5q31 region. Nevertheless, inactivation of both alleles in at least some cases suggests that deletions and mutations of the GRAF gene may be instrumental in the development and progression of hematopoeitic disorders with a del(5q). PMID:10908648

  10. The natural and human structuring of rivers and other geomorphological systems: A tribute to William L. Graf

    NASA Astrophysics Data System (ADS)

    Rhoads, Bruce L.

    2016-01-01

    This special issue honors the contributions of William L. Graf to geomorphology and river science. A hallmark of Will's work over the course of his career has been a focus on the natural and human structuring of river systems. More broadly, Will has been an innovator and leader who has shaped the way in which geomorphologists conduct research. Through his work, he has made fundamental contributions to basic fluvial theory, to the understanding of human impacts on river systems, and to policy-relevant science. He has demonstrated by example how to pursue policy-relevant science and to participate in science-based policy formulation. His contributions to river science can be classified into several themes: (1) the hydrology and geomorphology of suburban drainage systems, (2) riparian vegetation and river systems, (3) the spatial structure and dynamics of incised channels, (4) the dynamics of dryland river systems, (5) heavy metals in river systems, (6) dams and dam removal, and (7) water and public policy. The papers in this special issue reflect many aspects of these themes and address topics related to (1) the understanding of rivers and other geomorphic systems in the midst of dynamic physical change, (2) human influences on geomorphic processes, (3) the intersection of geomorphology and public policy, and (4) the fusion of geomorphic analysis and GIScience.

  11. GRAF - A GRACE follow-on mission feasibility study

    NASA Astrophysics Data System (ADS)

    Flechtner, F.; Neumayer, K. H.; Doll, B.; Munder, J.; Reigber, Ch.; Raimondo, J. C.

    2009-04-01

    After more than 6 years of very successful operation in orbit, the US-German GRACE mission has demonstrated in a very impressive way its outstanding capability to monitor mass motions in the Earth system with unprecedented accuracy and temporal resolution. These results have stimulated many novel research activities in hydrology, oceanography, glaciology, geophysics and geodesy, which also indicate that long term monitoring of such mass motions, possibly with improved spatial and temporal resolution is a must for further understanding of various phenomena. GRACE had been designed for 5 years lifetime, but due to the robust design and some margin on S/C consumables, GRACE can operate likely until 2012, thus about 10 years. Considering this, GFZ Potsdam has recently launched a short study with STI as industrial partner, holding a wealth of GRACE technical experience, to investigate the feasibility/boundaries of a follow on mission taking into account system, cost, programmatic and schedule aspects. An additional goal of the study is to work out some improvement in terms of temporal and spatial resolution, based on lessons learned from GRACE and based on further developed state of the art technology. These results will form the basis for further discussions with potential national and international partners in 2009. The presentation will focus on the main targets of the study.

  12. New erythroxane-type diterpenoids from Fagonia boveana (Hadidi) Hadidi & Graf.

    PubMed

    Gedara, Sahar R; Abdel-Halim, Osama B; el-Sharkawy, Saleh H; Salama, Osama M; Shier, Thomas W; Halim, Ahmed F

    2003-01-01

    The aerial parts of Fagonia boveana afforded two new erythroxane-type diterpenes, 3beta,15,16-trihydroxy-erythrox-4(18)-ene (2) and 15,16-dihydroxy-cis-ent-erythrox-3-ene (fagonene) (3) together with two known ones; 16-O-acetylfagonone (1) and 7beta-hydroxy fagonene (8). Also a new guaiane sesquiterpene alcohol, 6,10-epoxy-4alpha-hydroxy guaiane type sesquiterpene (4) has been isolated. In addition three 8-methoxy flavonols, 8-methoxy-quercetin-3,7,3'-trimethyl ether (ternatin) (5), gossypetin, 3,8,3',4' tetramethyl ether (6) and herbacetin-3,8-dimethyl ether (7) were also isolated. The structures of the isolated compounds have been determined on the basis of spectroscopic evidences as well as physical and chemical correlation with known compounds. On performing different assays for biological activities, 6 displayed significant cytotoxic activity against KA3IT and NIH3T3 cell lines, 8 was the most active antiviral against Herpes simplex type 1 while 7 was the most active cancer-preventive agent using protein-tyrosine kinase inhibitory method. PMID:12622221

  13. Canine atopic dermatitis - what have we learned?

    PubMed

    Nuttall, Tim; Uri, Maarja; Halliwell, Richard

    2013-02-23

    Canine atopic dermatitis is a complex multifactorial disease. Here, Tim Nuttall, Maarja Uri and Richard Halliwell, representing three generations of veterinary dermatologists, describe the research underpinning our understanding of the condition and highlight its relevance to clinical practice.

  14. A rapid algorithm for realistic human reaching and its use in a virtual reality system

    NASA Technical Reports Server (NTRS)

    Aldridge, Ann; Pandya, Abhilash; Goldsby, Michael; Maida, James

    1994-01-01

    The Graphics Analysis Facility (GRAF) at JSC has developed a rapid algorithm for computing realistic human reaching. The algorithm was applied to GRAF's anthropometrically correct human model and used in a 3D computer graphics system and a virtual reality system. The nature of the algorithm and its uses are discussed.

  15. Angels and Demons: The Science Behind the Scenes

    SciTech Connect

    Graf, Norman

    2009-05-12

    Does antimatter really exist? How and why do scientists produce and use it? Does CERN exist and is there an underground complex deep beneath the Swiss/French border? Is truth stranger than fiction? Find out at the coming public lecture. On Tuesday, May 12, SLAC physicist Norman Graf will discuss the real science behind Angels & Demons, Dan Brown's blockbuster novel and the basis of an upcoming Tom Hanks movie. Graf's' talk is one in a series of public lectures across the U.S., Canada and Puerto Rico to share the science of antimatter and the Large Hadron Collider, and the excitement of particle physics research.

  16. 77 FR 66084 - Quarterly Publication of Individuals, Who Have Chosen To Expatriate, as Required by Section 6039G

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-01

    ... MARY ADRIANOPOULOS GENIE IRENE ALBARRAK SAMI MANSOUR ANDERSON MARIE GABRIELLE APONTE ERICK ELVIS ARBENZ...- MARCI ANN BURG DEAN STEVEN DON DOUGLAS MARCELLE-LATRISE DRUCK JACOB ALEXANDER DUNN PETER WALLACE EWALD... GISI-TOLLE KERSTIN SANDRA GOEBEL GARY ROBERT GOLAN DANIEL SAM GRAF KAROLINE MADELEINE GUNTHARDT...

  17. 75 FR 69158 - Quarterly Publication of Individuals, Who Have Chosen To Expatriate, as Required by Section 6039G

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-10

    ... Jerome P. Auger Judy Ann Auyang William C. Azhar Shariq Azrieli Stephanie Joyce Bachman Mary Arnold... Mary Cook Dennis Eugene Corbett Meryle Lynn Corbin Tamara Diane Costelo Michael Philip Costelo... Gorr Marc-Andrew George Grace John S. Graf Robert Henri Grau Joachim Gray Laurence Brian Gray...

  18. Design under Constraints: The Case of Large-Scale Assessment Systems

    ERIC Educational Resources Information Center

    Mislevy, Robert J.

    2010-01-01

    In "Updating the Duplex Design for Test-Based Accountability in the Twenty-First Century," Bejar and Graf (2010) propose extensions to the duplex design for large-scale assessment presented in Bock and Mislevy (1988). Examining the range of people who use assessment results--from students, teachers, administrators, curriculum designers,…

  19. Quantifying the Impact of Physical Activity on Stress Tolerance in College Students

    ERIC Educational Resources Information Center

    Bland, Helen W.; Melton, Bridget F.; Bigham, Lauren E.; Welle, Paul D.

    2014-01-01

    Problem: Stress experience by millennial college students can be crippling. While stress is a universal and unavoidable phenomenon for college students, the variance in ability to handle stress can be attributed to stress tolerance (Welle & Graf, 2011). Research is needed to identify effective tools that increase college students' ability to…

  20. Gender Differences in Behavior-Related Special Education Supports in Elementary Students with Learning Disabilities

    ERIC Educational Resources Information Center

    Hassett, Kristen Spring

    2009-01-01

    Gender stereotypes abound in materials (AAUW, 1992; Kratovil & Bailey, 1986; Shafer & Shevitz, 2001), perceptions/expectations (AAUW; Stinnett, Bull, Koonce, & Aldridge, 1999), and vocational training (AAUW; Arms, Bickett, & Graf, 2008; Hanson & Smith, 2001). Achievement measures indicate that girls may be doing better than boys (Corbett, Hill, &…

  1. A Commentary on "Updating the Duplex Design for Test-Based Accountability in the Twenty-First Century"

    ERIC Educational Resources Information Center

    Brandt, Steffen

    2010-01-01

    This article presents the author's commentary on "Updating the Duplex Design for Test-Based Accountability in the Twenty-First Century," in which Isaac I. Bejar and E. Aurora Graf propose the application of a test design--the duplex design (which was proposed in 1988 by Bock and Mislevy) for application in current accountability assessments.…

  2. Descriptive properties of families of autohomeomorphisms of the unit interval

    NASA Astrophysics Data System (ADS)

    Glab, Szymon

    2008-07-01

    Let stand for the Polish space of all increasing autohomeomorphisms of [0,1]. We show that the family of all strictly singular autohomeomorphisms is -complete. This confirms a suggestion of Graf, Mauldin and Williams. Some related results are also included.

  3. Trauma and abuse in the case of Little Hans: a contemporary perspective.

    PubMed

    Ross, John Munder

    2007-01-01

    Newly available interviews with Max and Herbert Graf describe the severe pathology of Little Hans's mother and her mistreatment of her husband and her daughter, who committed suicide as an adult. Reread in this context, the text of "A Phobia in a Five-year-old Boy" provides ample evidence of Frau Graf's sexual seduction and emotional manipulation of her son, which exacerbated his age-expectable castration and separation anxiety, and her beating of her infant daughter. The boy's phobic symptoms can therefore be deconstructed not only as the expression of oedipal fantasy, but as a communication of the traumatic abuse occurring in the home. Through subliminal, indeed unconscious, injunctions conveyed in abusive behavior, parents can confirm the child's worst imaginings and immature views of the world and thereby render the child's oedipal conflicts and fantasies pathogenic. PMID:17915647

  4. The classical solution of a definite integral occurring in the satellite theory in the extended phase space

    NASA Technical Reports Server (NTRS)

    Bond, V. R.

    1979-01-01

    A method of integrating the functions defined by Scheifele and Graf (1974), arising in the elimination of time from the arguments of satellite theory using Delaunay elements in the extended phase space, is proposed. By repeated applications of an identity of Stiefel and Scheifele (1971), neglecting certain terms, and assuming a solution in the form of a product of Bessel functions, a solution expanded in the eccentricity is obtained.

  5. Stimulation of production of reactive oxygen and nitrogen species in endothelial cells by unmodified and Fenton-modified ultradisperse detonation diamond.

    PubMed

    Solarska-Ściuk, K; Gajewska, A; Skolimowski, J; Mitura, K; Bartosz, G

    2013-01-01

    In recent years, the development of nanotechnology opens up new prospects for biomedical applications of unmodified and chemically modified diamond nanoparticles (DNPs). The problem of biocompatibility of DNPs is thus of primary importance. The first step in the modification of DNPs is usually the introduction of -OH groups, which can bind other functional groups. One of the basic methods to introduce -OH groups onto DNPs is the Fenton reaction. The aim of this study was to compare the effect of unmodified DNPs and nanoparticles modified by the Fenton reaction on human endothelial cells. Ultradisperse diamond (UDD) was modified by the Fenton reaction introducing surface -OH groups. Immortalized human umbilical cord endothelial cells (HUVEC-ST) were incubated with 2-100 µg/mL nanopowders in the opti-MEM medium. For comparison, graphite powder (GRAF and GRAF+OH) was also employed. UDD and GRAF augmented generation of reactive oxygen species in the cells after 24 H incubation, estimated by oxidation of 2',7'-dichlorofluorescin diacetate (H2DCF-DA). Cellular production of nitric oxide, estimated with DAF-FM-DA (3-amino-4-aminomethyl 2',7'-dichlorofluorescein diacetate), was also affected by UDD and GRAF after 24 H. Fenton-modified OH, in contrast to unmodified diamond, decreased NO production. Detonation nanoparticles also affected the cellular content of glutathione and activities of main antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase). This article was published online on 5 February 2013. Errors in the byline and affiliation line were subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 18 April 2013. PMID:23586587

  6. Stimulation of production of reactive oxygen and nitrogen species in endothelial cells by unmodified and Fenton-modified ultradisperse detonation diamond.

    PubMed

    Solarska-Ściuk, K; Gajewska, A; Skolimowski, J; Mitura, K; Bartosz, G

    2013-01-01

    In recent years, the development of nanotechnology opens up new prospects for biomedical applications of unmodified and chemically modified diamond nanoparticles (DNPs). The problem of biocompatibility of DNPs is thus of primary importance. The first step in the modification of DNPs is usually the introduction of -OH groups, which can bind other functional groups. One of the basic methods to introduce -OH groups onto DNPs is the Fenton reaction. The aim of this study was to compare the effect of unmodified DNPs and nanoparticles modified by the Fenton reaction on human endothelial cells. Ultradisperse diamond (UDD) was modified by the Fenton reaction introducing surface -OH groups. Immortalized human umbilical cord endothelial cells (HUVEC-ST) were incubated with 2-100 µg/mL nanopowders in the opti-MEM medium. For comparison, graphite powder (GRAF and GRAF+OH) was also employed. UDD and GRAF augmented generation of reactive oxygen species in the cells after 24 H incubation, estimated by oxidation of 2',7'-dichlorofluorescin diacetate (H2DCF-DA). Cellular production of nitric oxide, estimated with DAF-FM-DA (3-amino-4-aminomethyl 2',7'-dichlorofluorescein diacetate), was also affected by UDD and GRAF after 24 H. Fenton-modified OH, in contrast to unmodified diamond, decreased NO production. Detonation nanoparticles also affected the cellular content of glutathione and activities of main antioxidant enzymes (superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, and glutathione S-transferase). This article was published online on 5 February 2013. Errors in the byline and affiliation line were subsequently identified. This notice is included in the online and print versions to indicate that both have been corrected 18 April 2013.

  7. A Fresh Wind is Blowing in from Asia Professor Michael Raghunath Arrives at ZHAW Waedenswil.

    PubMed

    Heinzelmann, Elsbeth

    2016-01-01

    In summer 2016, Michael Raghunath from the National University of Singapore (NUS) will take over the professorship from Ursula Graf-Hausner in cell culture technology and tissue engineering at ZHAW Life Sciences and Facility Management. What are his objectives and the corresponding strategies? What challenges will he face, what will he choose to focus on? Michael Raghunath was kind enough to let us have a look behind the scenes. PMID:27363381

  8. Automated calculations for massive fermion production with aı˚T ALC

    NASA Astrophysics Data System (ADS)

    Lorca, A.; Riemann, T.

    2004-10-01

    The package aı˚T ALC has been developed for the automated calculation of radiative corrections to two-fermion production at e+e- colliders. The package uses D IANA, Q GRAF, F ORM, F ORTRAN, FF, L OOPT OOLS, and further unix/linux tools. Numerical results are presented for e+e- → e+e-, μ+μ-, bs¯, tc¯.

  9. Discrepancy between sonographic and radiographic values after ultrasound-monitored treatment of developmental dysplasia of the hip

    PubMed Central

    Chita, Claudia; Paulus, Alexander C.; Guenther, Christian; Jansson, Volkmar; Heimkes, Bernhard

    2016-01-01

    Introduction The purpose of the study was to examine the accordance between the actually used sonographic and radiographic standard values after ultrasound-monitored treatment of developmental dysplasia of the hip (DDH). Material and methods One hundred and fifty-three (119 children) ultrasound-monitored treated hips (initial staging according to Graf: type IIc–IV) which attained normal ultrasound findings (type I according to Graf) during treatment and underwent an anteroposterior radiograph of the pelvis at the time of starting walking (mean age 18.6 months) were evaluated retrospectively. Results While all hips showed normal sonographic values (Graf type I), 26 (17%) showed mild and 17 (11.1%) severe dysplasia (by measuring the acetabular index) according to the radiographic Toennis classification system, and 29 (19%) showed mild and 48 (31.4%) severe dysplasia according to the Wiberg centre-edge angle. Conclusions This data show that the actually used sonographic and radiographic standard values concerning DDH do not correlate appropriately. It must be put up for discussion whether the radiographic standard values might be too strict. Further criteria must be developed to better assess the prognosis of residual dysplasia. PMID:26925130

  10. Commercialization of New Carbon Fiber Materials Based on Sustainable Resources for Energy Applications

    SciTech Connect

    Eberle, Cliff; Webb, Daniel C; Albers, Tracy; Chen, Chong

    2013-03-01

    Oak Ridge National Laboratory (ORNL) and GrafTech International have collaborated to develop and demonstrate the performance of high temperature thermal insulation prototypes made from lignin-based carbon fibers. This project will potentially lead to the first commercial application of lignin-based carbon fibers (LBCF). The goal of the commercial application is to replace expensive, Chinese-sourced isotropic pitch carbon fibers with lower cost carbon fibers made from a domestically sourced, bio-derived (renewable) feedstock. LBCF can help recapture jobs that were previously exported to China while resolving a supply chain vulnerability and reducing the production cost for GrafTech s high temperature thermal insulation. The performance of the LBCF prototypes was measured and found to be comparable to that of the current commercial product. During production of the insulation prototypes, ORNL and GrafTech demonstrated lignin compounding/pelletization, fiber production, heat treatment, and compositing at scales far surpassing those previously demonstrated in LBCF R&D or production. A plan was developed for the commercialization of LBCF thermal insulation, with key milestones including qualification of multiple scalable lignin sources in 2013, tons-scale production and field testing by customers in 2014, and product launch as soon thereafter as production capabilities can be constructed and commissioned.

  11. [Ultrasonography of the neonatal hip: state of the art and perspectives].

    PubMed

    Ortore, P; Fodor, G; Silverio, R; Milani, C; Psenner, K

    1996-01-01

    Since the first studies by Graf, medical interest for neonatal hip sonography (US) has grown, till the redefinition of the name itself of the pathologic condition, which has been recently renamed developmental dysplasia of the hip. After briefly reviewing our personal series of patients (18,388 hips studied from March, 1986, through June, 1995, with 2.81% positives according to Graf, 0.65% of them with subluxated hips), several issues are discussed relative to US of the neonatal hip in the study of dysplasia, namely: 1) technique, 2) measurements, 3) unstable hips, 4) screening, 5) protocols, 6) perspectives. Relative to the technique, Graf's method is currently the method of choice because it is easy to perform (single scanning) and repeatable, different from what other authors, particularly Novick and Harcke, suggested; they use a dynamic approach with more scans and different stress tests. Moreover, in Graf's technique, special attention is paid to the need for correct measurements, which phase was criticized by Couture who complained of its claimed complexity. Hip measurements are an important step in the study of this condition thanks to the information they yield the physician who can thus customize the therapy. The problem of the unstable hip and focal ligament laxity is discussed, which is hypothesized to be a possible cause of hip dysplasia misdiagnosis; according to Graf and Tönnis, this condition is related mostly to hormonal factors and has no actual clinical importance in the possible evolution to a pathologic condition. US of the neonatal hip must be set in a general screening program for newborns to be carried out by the 6th week of life to achieve optimal recovery in positive newborns, without limiting it to supposedly at risk groups. Moreover, the cost-benefit ratio of US screening is emphasized, provided that both medical staff and units are used correctly. A working diagnostic-therapeutic protocol is needed to plan standard epidemiologic

  12. [Computerized study of perioperative difficulties of stapedectomy].

    PubMed

    Cadavid Zink, R; Ballivian, H; Gamboa, F J; Olaizola, F

    1993-01-01

    A retrospective study of 1035 stapedectomies was performed to assess the incidence of intraoperative complications between 1972-1990. We found 45.89% of complications. We divided this alterations in 6 groups: 1) hemorrhage (20.67%), 2) stapes, foot plate, oval window (8.40%), 3) alterations in the middle ear (6.85%), 4) alterations in the incus (3.76%), 5) alterations in the external ear canal (3.57%) and 6) problems with protesis or graf (2.60%). We have analyzed these complications. We propose to carry out the solutions. PMID:8334004

  13. Next Generation Bipolar Plates for Automotive PEM Fuel Cells

    SciTech Connect

    Adrianowycz, Orest; Norley, Julian; Stuart, David J; Flaherty, David; Wayne, Ryan; Williams, Warren; Tietze, Roger; Nguyen, Yen-Loan H; Zawodzinski, Tom; Pietrasz, Patrick

    2010-04-15

    The results of a successful U.S. Department of Energy (DoE) funded two-year $2.9 MM program lead by GrafTech International Inc. (GrafTech) are reported and summarized. The program goal was to develop the next generation of high temperature proton exchange membrane (PEM) fuel cell bipolar plates for use in transportation fuel cell applications operating at temperatures up to 120 °C. The bipolar plate composite developed during the program is based on GrafTech’s GRAFCELL resin impregnated flexible graphite technology and makes use of a high temperature Huntsman Advanced Materials resin system which extends the upper use temperature of the composite to the DoE target. High temperature performance of the new composite is achieved with the added benefit of improvements in strength, modulus, and dimensional stability over the incumbent resin systems. Other physical properties, including thermal and electrical conductivity of the new composite are identical to or not adversely affected by the new resin system. Using the new bipolar plate composite system, machined plates were fabricated and tested in high temperature single-cell fuel cells operating at 120 °C for over 1100 hours by Case Western Reserve University. Final verification of performance was done on embossed full-size plates which were fabricated and glued into bipolar plates by GrafTech. Stack testing was done on a 10-cell full-sized stack under a simulated drive cycle protocol by Ballard Power Systems. Freeze-thaw performance was conducted by Ballard on a separate 5-cell stack and shown to be within specification. A third stack was assembled and shipped to Argonne National Laboratory for independent performance verification. Manufacturing cost estimate for the production of the new bipolar plate composite at current and high volume production scenarios was performed by Directed Technologies Inc. (DTI). The production cost estimates were consistent with previous DoE cost estimates performed by DTI for the

  14. The Present Status of Airship Construction, Especially of Airship-framing Construction

    NASA Technical Reports Server (NTRS)

    Ebner, Hans

    1938-01-01

    This work proposes to sketch, in broad outline, the status of airship construction in the various countries, at a time when commerce over great distances might be finally opened up to the airship through the performances of the "Graf Zeppelin." After a short historical review, a survey of the most important rigid and semirigid airships built since 1925, their differences and special problems, is made. In more detailed treatment, the framing construction of the more recent rigid airships and some especially interesting structural questions are investigated.

  15. Archive of single beam and swath bathymetry data collected nearshore of the Gulf Islands National Seashore, Mississippi, from West Ship Island, Mississippi, to Dauphin Island, Alabama: Methods and data report for USGS Cruises 08CCT01 and 08CCT02, July 2008, and 09CCT03 and 09CCT04, June 2009

    USGS Publications Warehouse

    DeWitt, Nancy T.; Flocks, James G.; Pendleton, Elizabeth A.; Hansen, Mark E.; Reynolds, B.J.; Kelso, Kyle W.; Wiese, Dana S.; Worley, Charles R.

    2012-01-01

    See the digital FACS equipment log for details about the acquisition equipment used. Raw datasets are stored digitally at the USGS St. Petersburg Coastal and Marine Science Center and processed systematically using Novatel's GrafNav version 7.6, SANDS version 3.7, SEA SWATHplus version 3.06.04.03, CARIS HIPS AND SIPS version 3.6, and ESRI ArcGIS version 9.3.1. For more information on processing refer to the Equipment and Processing page. Chirp seismic data were also collected during these surveys and are archived separately.

  16. The larvae of the European species of genus Apataniana Mosely, 1936 (Trichoptera, Apataniidae): descriptions, key and ecology.

    PubMed

    Waringer, Johann; Malicky, Hans

    2016-01-01

    This paper describes the previously unknown or insufficiently known larvae of Apataniana hellenica, Apataniana stropones and Apataniana vardusia. Species association was enabled by the fact that the three micro-endemic Apataniana larvae are restricted to Greece and the only Apataniidae species recorded in European ecoregion 6 (Hellenic Western Balkan; Graf et al. 2008), and that the endemic status of the three species clearly defined their non-overlapping sampling ranges. Information on the morphology of the larvae is given, and the most important diagnostic features are illustrated. PMID:27199610

  17. [Computerized study of perioperative difficulties of stapedectomy].

    PubMed

    Cadavid Zink, R; Ballivian, H; Gamboa, F J; Olaizola, F

    1993-01-01

    A retrospective study of 1035 stapedectomies was performed to assess the incidence of intraoperative complications between 1972-1990. We found 45.89% of complications. We divided this alterations in 6 groups: 1) hemorrhage (20.67%), 2) stapes, foot plate, oval window (8.40%), 3) alterations in the middle ear (6.85%), 4) alterations in the incus (3.76%), 5) alterations in the external ear canal (3.57%) and 6) problems with protesis or graf (2.60%). We have analyzed these complications. We propose to carry out the solutions.

  18. The larvae of the European species of genus Apataniana Mosely, 1936 (Trichoptera, Apataniidae): descriptions, key and ecology

    PubMed Central

    Waringer, Johann; Malicky, Hans

    2016-01-01

    Abstract This paper describes the previously unknown or insufficiently known larvae of Apataniana hellenica, Apataniana stropones and Apataniana vardusia. Species association was enabled by the fact that the three micro-endemic Apataniana larvae are restricted to Greece and the only Apataniidae species recorded in European ecoregion 6 (Hellenic Western Balkan; Graf et al. 2008), and that the endemic status of the three species clearly defined their non-overlapping sampling ranges. Information on the morphology of the larvae is given, and the most important diagnostic features are illustrated. PMID:27199610

  19. The Characterization of Grade PCEA Recycle Graphite Pilot Scale Billets

    SciTech Connect

    Burchell, Timothy D; Pappano, Peter J

    2010-10-01

    Here we report the physical properties of a series specimens machined from pilot scale (~ 152 mm diameter x ~305 mm length) grade PCEA recycle billets manufactured by GrafTech. The pilot scale billets were processed with increasing amounts of (unirradiated) graphite (from 20% to 100%) introduced to the formulation with the goal of determining if large fractions of recycle graphite have a deleterious effect on properties. The properties determined include Bulk Density, Electrical Resistivity, Elastic (Young s) Modulus, and Coefficient of Thermal Expansion. Although property variations were observed to be correlated with the recycle fraction, the magnitude of the variations was noted to be small.

  20. A carbon-14 depth profile in the L5 chondrite Knyahinya

    NASA Astrophysics Data System (ADS)

    Jull, A. J. T.; Donahue, D. J.; Reedy, R. C.; Masarik, J.

    1994-09-01

    We report on a series of measurements of C-14 in samples of the L-chondrite Knyahinya, as a function of depth. The results show C-14 concentrations ranging from 37 to 58 dpm/kg. These measurements are compared to the levels of Ne-21, Be-10 and noble-gas ratios in this meteorite reported by Graf et al (1990). We also compare the C-14 data to the expected profile based on two sets of model calculations. The behavior of this radioisotope with depth is similar to that expected from the models, and good agreement with the profiles of other nuclides is also observed.

  1. Theory of resonant multiphonon Raman scattering in graphene monolayers

    NASA Astrophysics Data System (ADS)

    Basko, Denis; Aleiner, Igor

    2007-03-01

    The Raman spectrum of graphene consists of distinct narrow peaks corresponding to different optical phonon branches as well as their overtones [1]. We show how the relative intensities of the overtone peaks encode information about relative strengths of different inelastic scattering processes electrons are subject to. In particular, assuming that the most important processes are electron-phonon and electron-electron scattering, it is shown that one can deduce their relative interaction strengths from the Raman spectra. [1] A. C. Ferrari et al., Phys. Rev. Lett. 97, 187401 (2006); A. Gupta et al., cond-mat/0606593; D. Graf et al., cond-mat/0607562.

  2. A carbon-14 depth profile in the L5 chondrite Knyahinya

    NASA Technical Reports Server (NTRS)

    Jull, A. J. T.; Donahue, D. J.; Reedy, R. C.; Masarik, J.

    1994-01-01

    We report on a series of measurements of C-14 in samples of the L-chondrite Knyahinya, as a function of depth. The results show C-14 concentrations ranging from 37 to 58 dpm/kg. These measurements are compared to the levels of Ne-21, Be-10 and noble-gas ratios in this meteorite reported by Graf et al (1990). We also compare the C-14 data to the expected profile based on two sets of model calculations. The behavior of this radioisotope with depth is similar to that expected from the models, and good agreement with the profiles of other nuclides is also observed.

  3. Proton stopping power measurements using high intensity short pulse lasers produced proton beams

    NASA Astrophysics Data System (ADS)

    Chen, S. N.; Atzeni, S.; Gauthier, M.; Higginson, D. P.; Mangia, F.; Marques, J.-R.; Riquier, R.; Fuchs, J.

    2014-03-01

    Proton stopping power measurements in solids and gases, typically made using proton accelerators, Van de Graf machines, etc., have existed now for many decades for many elements and compounds. We propose a new method of making this type of measurement using a different source, namely proton beams created by high intensity short pulse lasers. The advantage of this type of source is that there is the high number of particles and short bunch lengths, which is ideal for measurements of evolving mediums such as hot dense plasmas. Our measurements are consistent with exiting data and theory which validates this method.

  4. Universal Heat Transport in YBa_2Cu_3O_7-δ

    NASA Astrophysics Data System (ADS)

    Taillefer, Louis; Lussier, Benoit; Gagnon, Robert; Behnia, Kamran; Aubin, Hervé

    1997-03-01

    The thermal conductivity κ(T) of YBa_2Cu_3O_6.9 was measured along the a-axis of untwinned single crystals at very low temperatures (0.05 - 1 K). The magnitude of κ in these high-quality crystals is such that it significantly exceeds the maximum possible phonon contribution, thereby revealing unambiguously a dominant quasiparticle conduction at the lowest temperatures. The existence of uncondensed quasiparticles in clean samples at T=T_c/1000 is compelling evidence for an unconventional gap structure with nodes. Moreover, this quasiparticle contribution is essentially unaffected by the addition of up to 3% Zn impurities (which decreases the low-temperature electronic mean free path by a factor of up to 30). This remarkable insensitivity to impurity scattering is a direct confirmation of the universality of transport coefficients predicted for a superconductor with a gap that vanishes along a line of nodes(Patrick A. Lee, Phys. Rev. Lett. 71), 1887 (1993).^,2. Our results are compared with the recent calculations of Graf et al.(M.J. Graf, et al.), Phys. Rev. B 53, 15147 (1996). for a d_x^2-y^2 pairing state, and an excellent quantitative agreement is found for the universal T arrow 0 limit of κ/T.

  5. Gerhart Panning (1900-1944): a German forensic pathologist and his involvement in Nazi crimes during Second World War.

    PubMed

    Preuss, Johanna; Madea, Burkhard

    2009-03-01

    Twenty years after the Second World War the public were made aware of War Crimes committed by the German forensic pathologist, Gerhart Panning (1900-1944). From 1942 till 1944, Panning was professor at the Institute of Forensic Medicine at the University of Bonn. Panning died of tuberculosis on 22 March 1944. After the Second World War, Panning's widow tried to obtain denazification for her husband. There were no particularly serious doubts. In 1965, Konrad Graf von Moltke, the son of Helmuth James Graf von Moltke (1907-1944), presented to the court a private letter from his father to his mother. In this letter, written in 1941, Panning's experiments on Soviet prisoners are described. In the so-called Callsen trial in the court of Darmstadt from 1960 to 1968, the experiments were confirmed by witnesses. In 1941, Panning performed experiments in cooperation with the Sicherheitsstaffel (Nazi special police) in the Ukraine to prove that captured ammunition of the soviet infantry violated international law. For this purpose, different parts of the bodies of living Soviets were used as firing targets. He published the results of these experiments in a scientific journal without any evidence of the origin of these observations. In this article, Panning's life and crimes have been described. PMID:19237846

  6. DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

    SciTech Connect

    Elliot B. Kennel; Philip L. Biedler; Chong Chen; Dady Dadyburjor; Liviu Magean; Peter G. Stansberry; Alfred H. Stiller; John W. Zondlo

    2005-06-23

    The purpose of this DOE-funded effort is to develop continuous processes for solvent extraction of coal for the production of carbon products. These carbon products include materials used in metals smelting, especially in the aluminum and steel industries, as well as porous carbon structural material referred to as ''carbon foam'' and carbon fibers. There are a number of parameters which are important for the production of acceptable cokes, including purity, structure, density, electrical resistivity, thermal conductivity etc. From the standpoint of a manufacturer of graphite electrodes such as GrafTech, one of the most important parameters is coefficient of thermal expansion (CTE). Because GrafTech material is usually fully graphitized (i.e., heat treated at 3100 C), very high purity is automatically achieved. The degree of graphitization controls properties such as CTE, electrical resistivity, thermal conductivity, and density. Thus it is usually possible to correlate these properties using a single parameter. CTE has proven to be a useful index for the quality of coke. Pure graphite actually has a slightly negative coefficient of thermal expansion, whereas more disordered carbon has a positive coefficient.

  7. Gerhart Panning (1900-1944): a German forensic pathologist and his involvement in Nazi crimes during Second World War.

    PubMed

    Preuss, Johanna; Madea, Burkhard

    2009-03-01

    Twenty years after the Second World War the public were made aware of War Crimes committed by the German forensic pathologist, Gerhart Panning (1900-1944). From 1942 till 1944, Panning was professor at the Institute of Forensic Medicine at the University of Bonn. Panning died of tuberculosis on 22 March 1944. After the Second World War, Panning's widow tried to obtain denazification for her husband. There were no particularly serious doubts. In 1965, Konrad Graf von Moltke, the son of Helmuth James Graf von Moltke (1907-1944), presented to the court a private letter from his father to his mother. In this letter, written in 1941, Panning's experiments on Soviet prisoners are described. In the so-called Callsen trial in the court of Darmstadt from 1960 to 1968, the experiments were confirmed by witnesses. In 1941, Panning performed experiments in cooperation with the Sicherheitsstaffel (Nazi special police) in the Ukraine to prove that captured ammunition of the soviet infantry violated international law. For this purpose, different parts of the bodies of living Soviets were used as firing targets. He published the results of these experiments in a scientific journal without any evidence of the origin of these observations. In this article, Panning's life and crimes have been described.

  8. THERMAL INSULATION FROM LIGNIN-DERIVED CARBON FIBERS

    SciTech Connect

    Albers, Tracy; Chen, Chong; Eberle, Cliff; Webb, Daniel C

    2014-01-01

    Oak Ridge National Laboratory (ORNL) and GrafTech International Holdings Inc. (GrafTech) have collaborated to develop and demonstrate the performance of high temperature thermal insulation prototypes made from lignin-based carbon fibers (LBCF). This was the first reported production of LBCF or resulting products at scale > 1 kg. The results will potentially lead to the first commercial application of LBCF. The goal of the commercial application is to replace expensive, foreign-sourced isotropic pitch carbon fibers with lower cost carbon fibers made from a domestically sourced, bio-derived (renewable) feedstock. LBCF can help resolve supply chain vulnerability and reduce the production cost for high temperature thermal insulation as well as create US jobs. The performance of the LBCF prototypes was measured and found to be comparable to that of the current commercial product. During production of the insulation prototypes, the project team demonstrated lignin compounding/pelletization, fiber production, heat treatment, and compositing at scales far surpassing those previously demonstrated in LBCF R&D or production.

  9. A whole-space transform formula of cylindrical wave functions for scattering problems

    NASA Astrophysics Data System (ADS)

    Yuan, Xiaoming

    2014-03-01

    The theory of elastic wave scattering is a fundamental concept in the study of elastic dynamics and wave motion, and the wave function expansion technique has been widely used in many subjects. To supply the essential tools for solving wave scattering problems induced by an eccentric source or multi-sources as well as multi-scatters, a whole-space transform formula of cylindrical wave functions is presented and its applicability to some simple cases is demonstrated in this study. The transforms of wave functions in cylindrical coordinates can be classified into two basic types: interior transform and exterior transform, and the existing Graf's addition theorem is only suitable for the former. By performing a new replacement between the two coordinates, the exterior transform formula is first deduced. It is then combined with Graf's addition theorem to establish a whole-space transform formula. By using the whole-space transform formula, the scattering solutions by the sources outside and inside a cylindrical cavity are constructed as examples of its application. The effectiveness and advantages of the whole-space transform formula is illustrated by comparison with the approximate model based on a large cycle method. The whole-space transform formula presented herein can be used to perform the transform between two different cylindrical coordinates in the whole space. In addition, its concept and principle are universal and can be further extended to establish the coordinate transform formula of wave functions in other coordinate systems.

  10. Disparity between Clinical and Ultrasound Examinations in Neonatal Hip Screening

    PubMed Central

    Kyung, Bong Soo; Jeong, Woong Kyo; Park, Si Young

    2016-01-01

    Background For early detection of developmental dysplasia of the hip (DDH), neonatal hip screening using clinical examination and/or ultrasound has been recommended. Although there have been many studies on the reliability of both screening techniques, there is still controversy in the screening strategies; clinical vs. selective or universal ultrasound screening. To determine the screening strategy, we assessed the agreement among the methods; clinical examination by an experienced pediatric orthopedic surgeon, sonographic morphology, and sonographic stability. Methods From January 2004 to June 2009, a single experienced pediatric orthopedic surgeon performed clinical hip screenings for 2,686 infants in the neonatal unit and 43 infants who were referred due to impressions of hip dysplasia before 3 months of age. Among them, 156 clinically unstable or high-risk babies selectively received bilateral hip ultrasound examinations performed by the same surgeon using the modified Graf method. The results were analyzed statistically to detect any correlations between the clinical and sonographic findings. Results Although a single experienced orthopedic surgeon conducted all examinations, we detected only a limited relationship between the results of clinical and ultrasound examinations. Ninety-three percent of the clinically subluxatable hips were normal or immature based on static ultrasound examination, and 74% of dislocating hips and 67% of limited abduction hips presented with the morphology below Graf IIa. A total of 80% of clinically subluxatable, 42% of dislocating and 67% of limited abduction hips appeared stable or exhibited minor instability on dynamic ultrasound examination. About 7% of clinically normal hips were abnormal upon ultrasound examination; 5% showed major instability and 3% showed dysplasia above Graf IIc. Clinical stability had small coefficients between ultrasound examinations; 0.39 for sonographic stability and 0.37 for sonographic morphology

  11. The effect of guide-field and boundary conditions on the features and signatures of collisionless magnetic reconnection in a stressed X-point collapse

    NASA Astrophysics Data System (ADS)

    Graf von der Pahlen, J.; Tsiklauri, D.

    2015-12-01

    Magnetic X-point collapse is investigated using a 2.5D fully relativistic particle-in-cell simulation, with varying strengths of guide-field as well as open and closed boundary conditions. In the zero guide-field case we discover a new signature of Hall-reconnection in the out-of-plane magnetic field, namely an octupolar pattern, as opposed to the well-studied quadrupolar out-of-plane field of reconnection. The emergence of the octupolar components was found to be caused by ion currents and is a general feature of X-point collapse. In a comparative study of tearing-mode reconnection, signatures of octupolar components are found only in the out-flow region. It is argued that space-craft observations of magnetic fields at reconnection sites may be used accordingly to identify the type of reconnection [1][2]. Further, initial oscillatory reconnection is observed, prior to reconnection onset, generating electro-magnetic waves at the upper-hybrid frequency, matching solar flare progenitor emission. When applying a guide-field, in both open and closed boundary conditions, thinner dissipation regions are obtained and the onset of reconnection is increasingly delayed. Investigations with open boundary conditions show that, for guide-fields close to the strength of the in-plane field, shear flows emerge, leading to the formation of electron flow vortices and magnetic islands [3]. Asymmetries in the components of the generalised Ohm's law across the dissipation region are observed. Extended in 3D geometry, it is shown that locations of magnetic islands and vortices are not constant along the height of the current-sheet. Vortices formed on opposite sites of the current-sheet travel in opposite directions along it, leading to a criss-cross vortex pattern. Possible instabilities resulting from this specific structure formation are to be investigated [4].[1] J. Graf von der Pahlen and D. Tsiklauri, Phys. Plasmas 21, 060705 (2014), [2] J. Graf von der Pahlen and D. Tsiklauri

  12. Cosmic-ray production rates of He-, Ne- and Ar-isotopes in H-chondrites based on 36Cl-36Ar-ages

    NASA Astrophysics Data System (ADS)

    Leya, I.; Graf, Th.; Nishiizumi, K.; Wieler, R.

    2001-07-01

    We present the concentrations and isotopic compositions of He, Ne, and Ar for non-magnetic fractions and bulk samples of 17 H-chondrites which were recently investigated for their 36Cl-36Ar cosmic-ray exposure ages (Graf et al., 2001). All selected meteorites are observed falls with cosmic-ray exposure ages close to the 7 Ma peak. The rare gas data are consistent with 10Be and 36Cl production rates in the metal phase. Remarkably, only one out of the 17 H-chondrites, Bath, shows clear indications for a complex exposure history. Based on rare gas concentrations and 36Cl-36Ar exposure ages, 21Ne production rates as a function of 22Ne/21Ne and a mean 38Ar production rate are determined. The results confirm model calculations which predict that the relationship between 21Ne production rates and 22Ne/21Ne is ambiguous for high shielding. Besides the mean 38Ar production rate we also give production rate ratios P(38Ar from Ca) / P(38Ar from Fe). They vary between 10 and 77, showing no significant correlation with 38Ar-concentrations or 22Ne/21Ne. By investigating the metal-separates, Graf et al. (2001) found significant 3He deficits for six out of the 17 meteorites. For the non-magnetic fractions and bulk samples investigated here the data points in a 3He/21Ne versus 22Ne/21Ne diagram plot in the area defined by most of the H-chondrites. This means that 3He deficits in the metal phase are much more pronounced than in silicate minerals and we will argue that 3H diffusive losses in meteorites should be the rule rather than the exception. The 21Ne exposure ages, calculated on the basis of modeled 21Ne production rates, confirm the assumption by Graf et al. (2001) that the H5-chondrites with low 3He/38Ar in the metal formed in a separate event than those with normal 3He/38Ar ratios. The data can best be interpreted by assuming that the prominent 7 Ma exposure age peak of the H-chondrites is due to at least two events about 7.0 and 7.6 Ma ago.

  13. The generation effect and the modeling of associations in memory.

    PubMed

    Clark, S E

    1995-07-01

    The search of associative memory (SAM) model of Gillund and Shiffrin (1984) was applied to data of two experiments that examined the generation effect (Slamecka & Graf, 1978). Subjects studied a list of related word pairs, in which they either read both words in the pair or generated the right- hand response term using the left-hand stimulus term plus the response word fragment as generation cues. Experiment 1 manipulated encoding condition within subjects and used an incidental learning procedure. Experiment 2 manipulated encoding condition between subjects and used an intentional learning procedure. Memory was tested with recognition, cued recall, and free recall. A higher order association model gave a better and more parsimonious fit to the results than did an item-level association model. The relationship between various versions of SAM and current accounts of the generation effect are discussed, particulary the two-factor theory of Hirshman and Bjork (1988). PMID:7666757

  14. Modeling the snow cover in climate studies: 2. The sensitivity to internal snow parameters and interface processes

    NASA Astrophysics Data System (ADS)

    Loth, Bettina; Graf, Hans-F.

    1998-05-01

    In order to find an optimal complexity for snow-cover models in climate studies, the influence of single snow processes on both the snow mass balance and the energy fluxes between snow surface and atmosphere has been investigated. Using a sophisticated model, experiments were performed under several different atmospheric and regional conditions (Arctic, midlatitudes, alpine regions). A high simulation quality can be achieved with a multilayered snow-cover model resolving the internal snow processes (cf. part 1,[Loth and Graf, this issue]). Otherwise, large errors can occur, mostly in zones which are of paramount importance for the entire climate dynamics. Owing to simplifications of such a model, the mean energy balance of the snow cover, the turbulent heat fluxes, and the long-wave radiation at the snow surface may alter by between 1 W/m2 and 8 W/m2. The snow-surface temperatures can be systematically changed by about 10 K.

  15. Hydrodynamic interactions of water waves with a group of independently oscillating truncated circular cylinders

    NASA Astrophysics Data System (ADS)

    Zeng, Xiaohui; Shi, Min; Huang, Shanlin

    2016-07-01

    In this study, we examine the water wave radiation by arrays of truncated circular cylinders. Each cylinder can oscillate independently in any rigid oscillation mode with a prescribed amplitude, including translational and rotational modes such as surge, sway, heave, pitch, roll, and their combinations. Based on the eigenfunction expansion and Graf's addition theorem for Bessel functions, we developed an analytical method that includes the effects of evanescent modes in order to analyze such arrays of cylinders. To investigate the effects of several influential factors on convergence, our objective is to dramatically reduce the number of tests required and determine the influencing relationships between truncation number and convergence behavior for different factor combinations. We use the orthogonal test method to fulfill the objective. Lastly, we present our results regarding the effects of evanescent modes on hydrodynamic coefficients.

  16. Particle Analysis Pitfalls

    NASA Technical Reports Server (NTRS)

    Hughes, David; Dazzo, Tony

    2007-01-01

    This viewgraph presentation reviews the use of particle analysis to assist in preparing for the 4th Hubble Space Telescope (HST) Servicing mission. During this mission the Space Telescope Imaging Spectrograph (STIS) will be repaired. The particle analysis consisted of Finite element mesh creation, Black-body viewfactors generated using I-DEAS TMG Thermal Analysis, Grey-body viewfactors calculated using Markov method, Particle distribution modeled using an iterative Monte Carlo process, (time-consuming); in house software called MASTRAM, Differential analysis performed in Excel, and Visualization provided by Tecplot and I-DEAS. Several tests were performed and are reviewed: Conformal Coat Particle Study, Card Extraction Study, Cover Fastener Removal Particle Generation Study, and E-Graf Vibration Particulate Study. The lessons learned during this analysis are also reviewed.

  17. [The research on the surfacial modification of organic high-performance Kevlar fiber].

    PubMed

    Zheng, Yu-ying; Fu, Ming-lian; Cai, Wei-long; Wang, Can-yao; Wang, Liang-en

    2004-04-01

    In the paper the authors tried to use chemical disposal to bring the activity mass onto the surface of Kevlar fiber with the purpose of surface graft modification. In the paper the authors used the FTIR spectra to discuss the graft of toluene-2, 4-diisocyanate onto Kevlar fiber. The authors studied and analysed the effect of hydrolytic time on the content of -O-H group of the production, and the effect of hydrolyzation and hexyl-lactam steadily disposing on the graft reaction. The result showed that the content of -O-H group increased after hydrolyzation, it's helpful for the graft reaction, and hexyl-lactam steadily disposing made the graf product more stable. Through the research the authors came to the conclusion that by bringing some activity masses onto the fiber surface the authors can improve the interface of fiber/resin effectively.

  18. [White walls for black holes: essay on graffiti psychopathology].

    PubMed

    Catheline-Antipoff, N; Soulayrol, R

    1995-01-01

    Through a clinical case, the authors propose a psychological approach of tagging. The phenomenon that started in Harlem's black ghettos at the end of seventies and appeared in France less than ten years after, does not seem to be a simple sociological one, but seems to take place within the psychic economy of certain adolescents as an attempt to operate the necessary identity work to become an adult. Tagging as well as wandering can be considered adolescents' acting out behaviors and show the externalization of the psychic processes, thus proving a basic insecurity in their psychic space, invaded by anaclitic depression. Graffing, on the other hand, bears a resemblance to strolling in a psychopathologic approach, and already shows an attempt to become a person, and a quest of the Other. PMID:8657804

  19. TOF Electron Energy Analyzer for Spin and Angular Resolved Photoemission Spectroscopy

    NASA Astrophysics Data System (ADS)

    Lebedev, Gennadi; Jozwiak, Chris; Andresen, Nord; Hussain, Zahid; Lanzara, Alessandra

    2007-03-01

    Current pulsed laser and synchrotron x-ray sources provide new opportunities for Time-Of- Flight (TOF) based photoemission spectroscopy to increase photoelectron energy resolution and efficiency compared to current standard techniques. The principals of photoelectron timing front formation, temporal aberration minimization, and optimization of electron beam transmission are presented. We have developed these concepts into a high resolution a TOF Electron Energy Analyzer for photoemission spectroscopy. The electron optical scheme of the analyzer includes an electrostatic objective lens, three columns of transport lenses and a 90 degree energy band pass filter (BPF). High efficiency exchange scattering based spin polarimeter [1] is used for electron spin detection. The analyzer support two modes of operation: Spectrometer Mode allowing the entire spectrum to be measured, and Monochromator Mode in which the BPF passes a specified energy window inside the scope of the electron energy spectrum. [1] J. Graf, C. Jozwiak, A. K. Schmid, Z. Hussain, and A. Lanzara, Physical. Rev. B 71, 144429 (2005)

  20. [Squatting cast for biomechanical treatment of decentred hip joints].

    PubMed

    Mühlbacher, E; Lick-Schiffer, W; Lojpur, M; Baumgartner, F; Spieß, T; Tschauner, C

    2014-12-01

    The so-called "congenital" luxation of the hip joint is endemic in Central Europe and occurs in about 1% of all newborn infants. By the means of ultrasonographic diagnosis according to the Graf method an early detection instantly after birth has become a good clinical routine in the German-speaking countries. Sonography-based conservative treatment has become the gold standard. The cast in squatting ("human") position is a standard procedure in order to retain the originally decentred or unstable hip joints in the reduced position: 100° flexion and 50° abduction are necessary to fix the hip joint in the reduced position without the risk of avascular necrosis. After the fixation in a squatting-cast, a period of functional bracing in flexed position enhances bony maturation. This two-phase functional conservative treatment can avoid later osteotomies or even early total hip replacement.

  1. Treatment of Lignin Precursors to Improve their Suitability for Carbon Fibers: A Literature Review

    SciTech Connect

    Paul, Ryan; Naskar, Amit; Gallego, Nidia; Dai, Xuliang; Hausner, Andrew

    2015-04-17

    Lignin has been investigated as a carbon fiber precursor since the 1960s. Although there have been a number of reports of successful lignin-based carbon fiber production at the lab scale, lignin-based carbon fibers are not currently commercially available. This review will highlight some of the known challenges, and also the reported methods for purifying and modifying lignin to improve it as a precursor. Lignin can come from different sources (e.g. hardwood, softwood, grasses) and extraction methods (e.g. organosolv, kraft), meaning that lignin can be found with a diversity of purity and structure. The implication of these conditions on lignin as carbon fiber precursor is not comprehensively known, especially as the lignin landscape is evolving. The work presented in this review will help guide the direction of a project between GrafTech and ORNL to develop lignin carbon fiber technology, as part of a cooperative agreement with the DOE Advanced Manufacturing Office.

  2. The 21Ne production rate in quartz revisited

    NASA Astrophysics Data System (ADS)

    Niedermann, Samuel

    2000-12-01

    I have revised our earlier production rate determination of 21Ne in terrestrial quartz [S. Niedermann, Th. Graf, J.S. Kim, C.P. Kohl, K. Marti and K. Nishiizumi (1994) Earth Planet. Sci. Lett. 125, 341-355], taking account of improved knowledge about the exposure age of samples used in that work and applying distinct procedures for scaling to sea level and high latitudes. The corrected value of 19.0±3.7 atoms g -1 a -1 is in excellent agreement with expectations based on nuclear properties [J. Masarik and R.C. Reedy (1995) Earth Planet. Sci. Lett. 136, 381-395] and closely corresponds to the present-day production rate. In the case of substantial variations of the geomagnetic field in the past, as proposed by several studies, the revised value can consistently be used with suitable correction methods.

  3. Action semantics modulate action prediction.

    PubMed

    Springer, Anne; Prinz, Wolfgang

    2010-11-01

    Previous studies have demonstrated that action prediction involves an internal action simulation that runs time-locked to the real action. The present study replicates and extends these findings by indicating a real-time simulation process (Graf et al., 2007), which can be differentiated from a similarity-based evaluation of internal action representations. Moreover, results showed that action semantics modulate action prediction accuracy. The semantic effect was specified by the processing of action verbs and concrete nouns (Experiment 1) and, more specifically, by the dynamics described by action verbs (Experiment 2) and the speed described by the verbs (e.g., "to catch" vs. "to grasp" vs. "to stretch"; Experiment 3). These results propose a linkage between action simulation and action semantics as two yet unrelated domains, a view that coincides with a recent notion of a close link between motor processes and the understanding of action language.

  4. A new species of Limnephilidae (Insecta: Trichoptera) from the Western Alps (Insecta: Trichoptera)

    PubMed Central

    GRAF, WOLFRAM; VITECEK, SIMON

    2016-01-01

    A new species of the alpine caddisfly genus Consorophylax (Trichoptera, Limnephilidae, Stenophylacini) and the female of the recently described C. vinconi Graf & Malicky 2015 are described. The new species C. lepontiorum sp. nov. is a microendemic of the South-Western Alps and differs from its congeners in the shape of the superior and inferior appendages and the unique setation of the aedeagus, absent in all other Consorophylax species. The female of C. vinconi is characterized by the unique formation of the anal tube. Potential effects of alpine orogenesis, phenology and climatic oscillation on speciation of aquatic insects inhabiting high-altitude habitats are discussed. The description of C. lepontiorum sp. nov. accentuates the significance of the Western Alps as harbours of aquatic insect biodiversity, and demonstrates the necessity of faunal and taxonomic studies in Europe – a supposedly well-explored region. PMID:27069351

  5. NASA Lighting Research, Test, & Analysis

    NASA Technical Reports Server (NTRS)

    Clark, Toni

    2015-01-01

    The Habitability and Human Factors Branch, at Johnson Space Center, in Houston, TX, provides technical guidance for the development of spaceflight lighting requirements, verification of light system performance, analysis of integrated environmental lighting systems, and research of lighting-related human performance issues. The Habitability & Human Factors Lighting Team maintains two physical facilities that are integrated to provide support. The Lighting Environment Test Facility (LETF) provides a controlled darkroom environment for physical verification of lighting systems with photometric and spetrographic measurement systems. The Graphics Research & Analysis Facility (GRAF) maintains the capability for computer-based analysis of operational lighting environments. The combined capabilities of the Lighting Team at Johnson Space Center have been used for a wide range of lighting-related issues.

  6. Larval morphology and identification of Rhyacophila meyeri McLachlan 1879 (Trichoptera: Rhyacophilidae)

    PubMed Central

    WARINGER, JOHANN; VITECEK, SIMON; GRAF, WOLFRAM

    2016-01-01

    This paper describes the previously unknown larva of Rhyacophila meyeri McLachlan 1879. Information on the morphology of the 5th larval instar is given, and the most important diagnostic features are illustrated. In the context of existing identification keys the larva of R. meyeri keys together with R. stigmatica (Kolenati 1859). The species pair can be separated by differences in the setation pattern at the anterior pronotal border and maximum head width. With respect to zoogeography, Rhyacophila meyeri is reported from Switzerland and northern Italy whereas R. stigmatica is restricted to the Austrian, German and Swiss Alps and northern Slovenia (Cianficconi 2002; Graf et al. 2008; Lubini-Ferlin & Vicentini 2005; Malicky 2009; Robert 2004). PMID:27073321

  7. [White walls for black holes: essay on graffiti psychopathology].

    PubMed

    Catheline-Antipoff, N; Soulayrol, R

    1995-01-01

    Through a clinical case, the authors propose a psychological approach of tagging. The phenomenon that started in Harlem's black ghettos at the end of seventies and appeared in France less than ten years after, does not seem to be a simple sociological one, but seems to take place within the psychic economy of certain adolescents as an attempt to operate the necessary identity work to become an adult. Tagging as well as wandering can be considered adolescents' acting out behaviors and show the externalization of the psychic processes, thus proving a basic insecurity in their psychic space, invaded by anaclitic depression. Graffing, on the other hand, bears a resemblance to strolling in a psychopathologic approach, and already shows an attempt to become a person, and a quest of the Other.

  8. Membrane Fission Is Promoted by Insertion of Amphipathic Helices and Is Restricted by Crescent BAR Domains

    PubMed Central

    Boucrot, Emmanuel; Pick, Adi; Çamdere, Gamze; Liska, Nicole; Evergren, Emma; McMahon, Harvey T.; Kozlov, Michael M.

    2012-01-01

    Summary Shallow hydrophobic insertions and crescent-shaped BAR scaffolds promote membrane curvature. Here, we investigate membrane fission by shallow hydrophobic insertions quantitatively and mechanistically. We provide evidence that membrane insertion of the ENTH domain of epsin leads to liposome vesiculation, and that epsin is required for clathrin-coated vesicle budding in cells. We also show that BAR-domain scaffolds from endophilin, amphiphysin, GRAF, and β2-centaurin limit membrane fission driven by hydrophobic insertions. A quantitative assay for vesiculation reveals an antagonistic relationship between amphipathic helices and scaffolds of N-BAR domains in fission. The extent of vesiculation by these proteins and vesicle size depend on the number and length of amphipathic helices per BAR domain, in accord with theoretical considerations. This fission mechanism gives a new framework for understanding membrane scission in the absence of mechanoenzymes such as dynamin and suggests how Arf and Sar proteins work in vesicle scission. PMID:22464325

  9. Soliton Wall Superlattice in the Quasi-One-Dimensional Conductor (Per)2Pt(mnt)2

    NASA Astrophysics Data System (ADS)

    Lebed, A. G.; Wu, Si

    2007-07-01

    We suggest a model to explain the appearance of a high resistance high magnetic field charge-density-wave (CDW) phase, discovered by Graf et al. [Phys. Rev. Lett. 93, 076406 (2004)PRLTAO0031-900710.1103/PhysRevLett.93.076406] in (Per)2Pt(mnt)2, where Per is perylene and mnt is maleonitriledithiolate molecules. In particular, we show that the Pauli spin-splitting effects improve the nesting properties of a realistic quasi-one-dimensional electron spectrum and, therefore, a high resistance Peierls CDW phase is stabilized in high magnetic fields. In low and very high magnetic fields, a periodic soliton wall superlattice (SWS) phase is found to be a ground state. We suggest experimental studies of the predicted phase transitions between the Peierls and SWS CDW phases in (Per)2Pt(mnt)2 to discover a unique SWS phase.

  10. Measuring the off axis magnetic field within a Helmholtz Coil

    NASA Astrophysics Data System (ADS)

    Pluhar, Edward; Martell, Eric

    2013-03-01

    Helmholtz coils are used because they produce nearly uniform magnetic fields on-axis. Prior research, namely Graf's thin coil experiment [The Physics Teacher, pp. 360 (2012)], has accurately measured the axial magnetic field produced by a thin coil; however, the magnetic field off-axis is known to be significantly more complicated and cannot be calculated analytically. In this research, I have numerically determined the magnetic field off-axis in the region between the two coils and compared those calculations with measured values. I then determined the effect the deviation from uniformity has on the behavior of a charged particle moving through this region, such as in the well-known electron charge-to-mass ratio experiment.

  11. Influence of the modulation index of Mach-Zehnder modulator on intersatellite microwave photonics links with multiple RF signals

    NASA Astrophysics Data System (ADS)

    Zhu, Zihang; Zhao, Shanghong; Li, Yongjun; Chu, Xingchun; Hou, Rui

    2013-04-01

    A generalized intersatellite microwave photonics links model to study the influence of the modulation index of Mach-Zehnder modulator on the receiver sensitivity with multiple radio frequency (RF) signals is presented. An exact analytical solution of signal-to-noise and distortion ratio (SNDR) for optical double-sideband (ODSB) and optical single-sideband (OSSB) modulation is deduced with Bessel expansion and Graf's addition theorem. Numerical results show that the receiver sensitivity increases and then decreases as the increase in modulation index, there is an optimum modulation index that maximizes the receiver sensitivity and the larger channel numbers lead to lower receiver sensitivity for maintaining the SNDR at the desired level. In addition, ODSB modulation can be more attractive than OSSB modulation in intersatellite microwave photonics links, since the maximum receiver sensitivity for ODSB modulation is better than that for OSSB modulation.

  12. Towards Asymptotic Completeness of Two-Particle Scattering in Local Relativistic QFT

    NASA Astrophysics Data System (ADS)

    Dybalski, Wojciech; Gérard, Christian

    2014-02-01

    We consider the problem of existence of asymptotic observables in local relativistic theories of massive particles. Let and be two energy-momentum vectors of a massive particle and let be a small neighbourhood of . We construct asymptotic observables (two-particle Araki-Haag detectors), sensitive to neutral particles of energy-momenta in small neighbourhoods of and . We show that these asymptotic observables exist, as strong limits of their approximating sequences, on all physical states from the spectral subspace of . Moreover, the linear span of the ranges of all such asymptotic observables coincides with the subspace of two-particle Haag-Ruelle scattering states with total energy-momenta in . The result holds under very general conditions which are satisfied, for example, in . The proof of convergence relies on a variant of the phase-space propagation estimate of Graf.

  13. High Magnetic Field Properties of Ce2Rh3Ge5

    NASA Astrophysics Data System (ADS)

    Wartenbe, Mark

    2015-03-01

    The competition between localized and delocalized f electrons in heavy fermion materials produces a wide variety of interesting physical phenomena. Among these compounds is Ce2Rh3Ge5. This heavy-fermion system undergoes an antiferromagnetic transition below 4K and exhibits an angle dependent magnetic phase transition around 25 tesla. In addition, RF conductivity measurements in pulsed field (65T) have revealed quantum oscillations. Temperature dependence at fixed angle indicates relatively heavy effective masses of values ranging from around 3me on up to 10me. This indicates that the narrow f-electron density of states is partially hybridized close to the Fermi energy, but also places strict cryogenic constraints upon the measurement (3Helium temperatures are required). Fermi surface calculations have produced complex figures which lend validation to such rich behavior. Ryan Baumbach, Andrew Gallagher, Eric Bauer, Ross McDonald, Kuan-Wen Chen,David Graf.

  14. Cosmogenic nuclides in core samples of the Chico L6 chondrite - Evidence for irradiation under high shielding

    NASA Technical Reports Server (NTRS)

    Garrison, D. H.; Bogard, D. D.; Albrecht, A. A.; Vogt, S.; Herzog, G. F.; Klein, J.; Fink, D.; Dezfouly-Arjomandy, B.; Middleton, R.

    1992-01-01

    Results are presented from an analysis of core samples obtained from different depths of the Chico (New Mexico) L6 chondrite for various cosmogenic nuclides (Be-10, Al-26, and stable isotopes of He, Ne, and Ar). The relationships between the measured abundances of cosmogenic nuclides and cosmogenic Ne-22/Ne-21 ratio were compared with predictions of recent semiempirical models of Graf et al. (1990) and Reedy (1991), and it was found that both models closely reproduce the observed trends and absolute values of the data obtained. Noble gas data indicate that Chico experienced shielding similar to that of Jilin and greater than those of the Knyahinya or the Keyes chondrites. The exposure history for Chico is discussed.

  15. Have Large Dams Altered Extreme Precipitation Patterns?

    NASA Astrophysics Data System (ADS)

    Hossain, Faisal; Jeyachandran, Indumathi; Pielke, Roger

    2009-12-01

    Dams and their impounded waters are among the most common civil infrastructures, with a long heritage of modern design and operations experience. In particular, large dams, defined by the International Commission on Large Dams (ICOLD) as having a height greater than 15 meters from the foundation and holding a reservoir volume of more than 3 million cubic meters, have the potential to vastly transform local climate, landscapes, regional economics, and urbanization patterns. In the United States alone, about 75,000 dams are capable of storing a volume of water equaling almost 1 year's mean runoff of the nation [Graf, 1999]. The World Commission on Dams (WCD) reports that at least 45,000 large dams have been built worldwide since the 1930s. These sheer numbers raise the question of the extent to which large dams and their impounded waters alter patterns that would have been pervasive had the dams not been built.

  16. Comment on ``Vortex-assisted photon counts and their magnetic field dependence in single-photon superconducting detectors''

    NASA Astrophysics Data System (ADS)

    Gurevich, A.; Vinokur, V. M.

    2012-07-01

    We discuss the importance of the vortex core energy and realistic boundary conditions to the Fokker-Plank equation for the calculation of thermally activated hopping of vortices across narrow superconducting films. Disregard of these issues in the papers by Bulaevskii, Graf and Kogan, Phys. Rev. BPRBMDO1098-012110.1103/PhysRevB.85.014505 85, 014505 (2012) and by Bulaevskii , Phys. Rev. BPRBMDO1098-012110.1103/PhysRevB.83.144526 83, 144526 (2011) in which an uncertain London vortex core cutoff was used, can produce large numerical errors and a significant discrepancy between their results and the results of the paper by Gurevich and Vinokur, Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.100.227007 100, 227007 (2008) in which these issues were taken into account. This can be essential for the interpretation of experimental data on thin-film photon detectors and other superconducting nanostructures.

  17. On the arithmetic sums of Cantor sets

    NASA Astrophysics Data System (ADS)

    Ilgar Eroglu, Kemal

    2007-05-01

    Let Cλ and Cγ be two affine Cantor sets in \\mathbb{R} with similarity dimensions dλ and dγ, respectively. We define an analogue of the Bandt-Graf condition for self-similar systems and use it to give necessary and sufficient conditions for having \\xyHa^{d_\\xyla+d_\\xyga}(C_\\xyla + C_\\xyga)>0 where Cλ + Cγ denotes the arithmetic sum of the sets. We use this result to analyse the orthogonal projection properties of sets of the form Cλ × Cγ. We prove that for Lebesgue almost all directions θ for which the projection is not one-to-one, the projection has zero (dλ + dγ)-dimensional Hausdorff measure. We demonstrate the results in the case when Cλ and Cγ are the middle-(1-2λ) and middle-(1-2γ) sets.

  18. High TC half-metallic fully-compensated ferrimagnetic Heusler compounds

    NASA Astrophysics Data System (ADS)

    Galanakis, I.; Şaşıoǧlu, E.

    2011-08-01

    Extensive ab-initio electronic structure calculations on Heusler alloys suggest that Cr2CoGa is the alloy of choice to achieve the half-metallic fully-compensated ferrimagnetism since (1) it has been already grown experimentally [T. Graf et al., Z. Anorg. Allg. Chem. 635, 976 (2009)], (2) half-metallic XA structure is favored energetically over all the studied lattice constant range with respect to the L21 which is not half-metallic, (3) the half-metallic gap is wide and the Fermi level falls at the middle of the gap and thus, it presents high degree of spin-polarization for a wide range of lattice constants, and (4) the Curie temperature is extremely high reaching the 1520 K.

  19. Cosmogenic nuclides in core samples of the Chico L6 chondrite - Evidence for irradiation under high shielding

    NASA Astrophysics Data System (ADS)

    Garrison, D. H.; Bogard, D. D.; Albrecht, A. A.; Vogt, S.; Herzog, G. F.; Klein, J.; Fink, D.; Dezfouly-Arjomandy, B.; Middleton, R.

    1992-09-01

    Results are presented from an analysis of core samples obtained from different depths of the Chico (New Mexico) L6 chondrite for various cosmogenic nuclides (Be-10, Al-26, and stable isotopes of He, Ne, and Ar). The relationships between the measured abundances of cosmogenic nuclides and cosmogenic Ne-22/Ne-21 ratio were compared with predictions of recent semiempirical models of Graf et al. (1990) and Reedy (1991), and it was found that both models closely reproduce the observed trends and absolute values of the data obtained. Noble gas data indicate that Chico experienced shielding similar to that of Jilin and greater than those of the Knyahinya or the Keyes chondrites. The exposure history for Chico is discussed.

  20. Specific heat and materials analysis on U_1-xTh_xPt3 for 0 ≤ x ≤ 0.05

    NASA Astrophysics Data System (ADS)

    Hettinger, J. D.; Cooley, J. C.; Smith, J. L.; Peterson, E. J.; Hackenberg, R. E.; Kelly, A. M.; Papin, P. A.; de Visser, A.; Graf, M. J.

    2004-03-01

    UPt3 exhibits anomalous, possibly time-fluctuating antiferromagnetic (AFM) order below 6K that is only detectable via neutron and x-ray scattering. Th substitution induces conventional AFM order with the same magnetic structure and an ordering temperature TN ≤ 6 K. Recent μSR studies on U_1-xTh_xPt3 for 0 ≤ x ≤ 0.05 showed that the transition from the anomalous into conventional antiferromagnetic state was very broad (Graf et al., Phys. Rev. B 68,in press), indicative of a crossover behavior. X-ray diffraction and high-resolution transmission electron microscopy show no evidence for chemical or material inhomogeneity. Nonetheless, specific heat measurements corroborate the μSR measurements and show signs of an increase near 6K for x ≥ 0.01. This supports the conjecture that Th impurities slow down the fluctuating AFM, rendering them observable on the timescale of thermodynamic measurements.

  1. [On natural history museums and their purpose. A lecture given by Leopold von Buch (1774-1853) in April 1838].

    PubMed

    Kröger, Björn

    2011-12-01

    A manuscript of a lecture by the Prussian geologist Leopold von Buch given at the Berlin Society of the Friends of the Humanity was discovered at the Museum für Naturkunde, Berlin. The text is a raw version of a passionate plea for the formation of natural history collections as science places, with a partly biting humor. Based on until now unknown anecdotes about naturalists like Kaspar Maria Graf Sternberg (1761-1838) and Friedrich Wilhelm Hoeninghaus (1771-1854) Leopold von Buch argues with von Sternberg for the scientific value of natural history collections. The repeating references to the works of Goethe and an extensive addendum of various Dante translations into German are striking. The lecture manuscript complements our knowledge about the thinking of this important geologist, and provides new insights into the science policy of his time.

  2. Targeted Screening of Hip Dysplasia in Newborns: Experience at a District General Hospital in Scotland

    PubMed Central

    Tyagi, Rahul; Zgoda, Marcin R.; Short, Rachel

    2016-01-01

    National Health Service Quality Improvement Scotland (NHS QIS) published a health technology scoping report in 2006 acknowledging that there are serious concerns within Scotland in relation to Developmental Dysplasia of Hip (DDH) as there is no formal screening program in place and there are significant variations between NHS boards leading to confusion for staff and parents. NHS QIS identified need for audit work to improve hip screening in Scotland. The aim of this study is review of current practice of selective screening for DDH. All newborns who had their first hip scan during one year period (2014) were included in this retrospective study and followed up until June 2015 to include any surgical intervention for dysplastic hip. Out of 428 babies (856 hip scans), abnormality was seen in 119 babies/147 hips (134 Graf 2a/2b, 10 hips were 2c and 3 hips were Graf grade 3). Average age when first scan was performed was 5 weeks (range 3 weeks to 22 weeks). Analysis of risk factors in 119 babies with abnormal scan was consistent with literature (83 breech, 12 family history, 12 HBW, 10 instability and 2 twins of breech). Twelve babies (16 hips) required treatment and were successfully treated in Pavlik harness. There was one case of missed/late dislocation, which lived in outside catchment area for 3 years since birth. During this study period there was no case of avascular necrosis or femoral nerve palsy as a result of treatment. In our experience, selective hip screening by ultrasound scan is useful in avoiding overtreatment and minimizing late presentations. PMID:27761220

  3. Development and maintenance of a telescoping debris flow fan in response to human-induced fan surface channelization, Chalk Creek Valley Natural Debris Flow Laboratory, Colorado, USA

    NASA Astrophysics Data System (ADS)

    Wasklewicz, T.; Scheinert, C.

    2016-01-01

    Channel change has been a constant theme throughout William L. Graf's research career. Graf's work has examined channel changes in the context of natural environmental fluctuations, but more often has focused on quantifying channel change in the context of anthropogenic modifications. Here, we consider how channelization of a debris flows along a bajada has perpetuated and sustained the development of 'telescoping' alluvial fan. Two-dimensional debris-flow modeling shows the importance of the deeply entrenched channelized flow in the development of a telescoping alluvial fan. GIS analyses of repeat (five different debris flows), high-resolution (5 cm) digital elevation models (DEMs) generated from repeat terrestrial laser scanning (TLS) data elucidate sediment and topographic dynamics of the new telescoping portion of the alluvial fan (the embryonic fan). Flow constriction from channelization helps to perpetuate debris-flow runout and to maintain the embryonic fan and telescoping nature of the alluvial fan complex. Embryonic fan development, in response to five debris flows, proceeds with a major portion of the flows depositing on the southern portion of the embryonic fan. The third through the fifth debris flows also begin to shift some deposition to the northern portion of the embryonic. The transfer of sediment from a higher portion of the embryonic fan to a lower portion continues currently on the embryonic fan. While channelized flow has been shown to be critical to the maintenance of the telescoping fan, the flow constriction has led to higher than background levels of sediment deposition in Chalk Creek, a tributary of the Arkansas River. A majority of the sediment from each debris flow is incorporated into Chalk Creek as opposed to being stored on the embryonic fan.

  4. Comparing results of clinical versus ultrasonographic examination in developmental dysplasia of hip

    PubMed Central

    Arti, Hamidreza; Mehdinasab, Seyed Abdoulhossein; Arti, Sara

    2013-01-01

    Background: Developmental dysplasia of hip (DDH) is one of the congenital anomalies in newborns that if not diagnosed and treated on time can lead to a severe disability. Although clinical examination is a very useful way for screening, but in some patients, a confirmatory diagnostic method such as ultrasonography is needed. The aim of the present study is to compare the sensitivity and specificity of clinical examination and ultrasonography in early detecting of DDH. Materials and Methods: A total of 5800 of newborns were examined by orthopedic surgeon as a screening method. The newborns with risk factors or suspicious on clinical examination were introduced to repeat clinical and ultrasonographic examination of hip. The results were collected and recorded by a check list and then the sensitivity and specificity of clinical examination were calculated. Results: Of 5701 newborns (11402 hips) who were studied by two methods of clinical examination and ultrasonography (by Graf method), the overall incidence of DDH was 29 per 1000. Only 94 hips (13.5%) of 694 disordered ones according to clinical examination were involved on ultrasonographic evaluation. A total of 240 hips of 334 (72%) involved hips according to ultrasonography (Graf type IIb or more) were diagnosed normal on clinical examination, considering ultrasonography as a gold standard method of evaluating DDH, the sensitivity and specificity of clinical examination were calculated 28.1% and 94.5%, respectively. Conclusion: According to the present study, ultrasonogeraphic examination has a high valuable in screening of DDH and the clinical examination done by an experienced orthopedic surgeon has an acceptable value in primary screening of DDH in developing countries for detecting of healthy neonates, but if the newborn has a risk factor or is suspicious on clinical examination, it will be necessary to get assistance from ultrasonography by an experienced sonographer. PMID:24523795

  5. Effect of increase in birth weight in a newborn on hip ultrasonography.

    PubMed

    Orak, Mehmet M; Karaman, Ozgur; Gursoy, Tugba; Cagirmaz, Talat; Oltulu, Ismail; Muratli, Hasan H

    2015-11-01

    Exposure to the pressure experienced by higher birth weight babies during the intrauterine period might cause hip dysplasia. The aim of this study is to determine the effect of birth weight in newborns on hip ultrasonography when the paternal and maternal risk factors are excluded. A total of 701 babies born at 38-42 gestational weeks were included in the study. Hip ultrasonography was performed within 7 days following birth using the Graf technique in the babies without risk factors for developmental dysplasia of the hip. Images obtained were controlled with respect to conformity to the Graf method and angular measurements were performed. According to the α and β angle values obtained, type 1A and 1B hips were categorized as mature; type 2A hips were categorized as immature; and type 2C, D, 3A, 3B, and 4 hips were categorized as pathological hips. The results obtained were analyzed for the effect of birth weight on the angular values and hip typing. The birth weight of the babies was 338,488 ± 48,241 g (2030-6124 g). It was determined that the birth weight had no effect on the values of α and β angles in the male babies (P=0.21, 0.76). It was determined that increasing birth weight decreased the α angle value (P=0.001) and caused no difference in the β angle value (P=0.057) in the female babies. It was found that birth weight had no effect on hip typing in both female and male babies (P=0.060, 0.22). Increases in birth weights caused decreases in ultrasonographic α angles only in female babies. PMID:26196367

  6. Measurement and Validation of Bidirectional Reflectance of Space Shuttle and Space Station Materials for Computerized Lighting Models

    NASA Technical Reports Server (NTRS)

    Fletcher, Lauren E.; Aldridge, Ann M.; Wheelwright, Charles; Maida, James

    1997-01-01

    Task illumination has a major impact on human performance: What a person can perceive in his environment significantly affects his ability to perform tasks, especially in space's harsh environment. Training for lighting conditions in space has long depended on physical models and simulations to emulate the effect of lighting, but such tests are expensive and time-consuming. To evaluate lighting conditions not easily simulated on Earth, personnel at NASA Johnson Space Center's (JSC) Graphics Research and Analysis Facility (GRAF) have been developing computerized simulations of various illumination conditions using the ray-tracing program, Radiance, developed by Greg Ward at Lawrence Berkeley Laboratory. Because these computer simulations are only as accurate as the data used, accurate information about the reflectance properties of materials and light distributions is needed. JSC's Lighting Environment Test Facility (LETF) personnel gathered material reflectance properties for a large number of paints, metals, and cloths used in the Space Shuttle and Space Station programs, and processed these data into reflectance parameters needed for the computer simulations. They also gathered lamp distribution data for most of the light sources used, and validated the ability to accurately simulate lighting levels by comparing predictions with measurements for several ground-based tests. The result of this study is a database of material reflectance properties for a wide variety of materials, and lighting information for most of the standard light sources used in the Shuttle/Station programs. The combination of the Radiance program and GRAF's graphics capability form a validated computerized lighting simulation capability for NASA.

  7. Reaction Driven Shear Localization: the Example From Torsion Experiments on Dolomite

    NASA Astrophysics Data System (ADS)

    Delle Piane, C.; Burlini, L.; Grobety, B.

    2005-12-01

    We performed torsion experiments using a Paterson rig apparatus on cylindrical (diam = 1cm; H = 1cm) samples of natural specimen of pure dolomite (<0.3 wt % of impurities on XRF analysis), drilled on a block of the Dolomia from Mt. Frerone (Adamello, N-Italy). Experiments were run at 800°, 300 MPa confining pressure under vented and non-vented conditions, up to a bulk strain of about γ =1, at different strain rates (3*10-5s-1 up to 1*10-4s-1). Deformation was localized near both porous spacers placed at the extremities of the specimen, corresponding to the zone were dolomite broke down into a fine grained mixture of calcite and periclase according to the reaction: CaMg(CO3)2=CaCO3 + MgO + CO2. At these conditions the nominal equilibrium PCO2 should be around 70 MPa (Graf and Goldsmith 1955), but at the spacer interface the CO2 was free to escape, triggering the reaction. On the other hand, in the central part of the sample, the reaction occurred only along the grain boundaries of the dolomite grains. Due to the low permeability pore fluid could not escape building up CO2 pressure which deactivated the reaction. Here deformation was accommodated by brittle shear bands in synthetic Riedel geometry, consistently oriented with the sense of shear; these bands do not extend up to the sample-spacers. We conclude that the decarbonatation reaction produced a weaker matrix in which deformation could localize. Moreover, the very fine grain size was probably produced during the decarbonatation reaction, and was kept small by the deformation due to pinning between the different phases. Graf, D. L. and J. R. Goldsmith (1955). ``Dolomite-magnesian calcite relations at elevated temperatures and CO2 pressure." Geochimica et cosmochimica acta 7: 109-128.

  8. A Single Lodranite/Acapulcoite Parent Body: Noble Gases in Lodranite QUE 93148 and Acapulcoite ALH 81261

    NASA Astrophysics Data System (ADS)

    Weigel, A.; Eugster, O.; Marti, K.; Michel, R.

    1995-09-01

    We continue our comprehensive studies of the cosmic ray exposure history of lodranites [1] to include new noble gas measurements in the QUE 93148 lodranite and the ALH 81261 acapulcoite. In addition, we model the production rates of cosmogenic nuclides in lodranites and acapulcoites using the HERMES high energy transport code [2], in order to test whether conventional production rates can be extrapolated to this group of small meteoroids which reveal very large values of the shielding parameter 22Ne/21Ne (Table 1). The model calculations are based on the same excitation functions of p- and n-induced reactions as used in recent calculations [3,4]. We extended our studies to acapulcoites, since petrologic, mineralogic, and O-isotopic investigations [5] as well as chemical investigations [6] suggest that lodranites and acapulcoites are residues of varying degree of partial melting, consistent with an origin on a common parent body. Whether a collisional event on the common parent body ejected both types of meteorites can be investigated by an analysis of the transfer times to Earth, specifically their cosmic-ray exposure ages. Because the contents of trapped He, Ne, and Ar in lodranites and acapulcoites are very low we can derive reliable cosmogenic noble gas contents. Using the composition-adjusted production rates for cosmogenic noble gases in achondrites [7], and adopting the shielding-parameter dependence for H-chondrites the exposure ages of [1] are obtained. For lodranites these exposure ages overlap those calculated [8] from 26Al and 10Be measurements. For the acapulcoites our exposure ages agree with those [5] calculated with the Graf-model [9], as well as with the shielding-independent exposure age for Acapulco that is based on the 36Cl-36Ar method[10]. The large spread in the exposure ages can be attributed to the highly variable target element abundances, as multiple measurements on several aliquots show unusually large variations. The fact that the average

  9. VAXCMS - VAX CONTINUOUS MONITORING SYSTEM, VERSION 2.2

    NASA Technical Reports Server (NTRS)

    Farkas, L.

    1994-01-01

    The VAX Continuous Monitoring System (VAXCMS) was developed at NASA Headquarters to aid system managers in monitoring the performance of VAX systems through the generation of graphic images which summarize trends in performance metrics over time. Since its initial development, VAXCMS has been extensively modified at the NASA Lewis Research Center. Data is produced by utilizing the VMS MONITOR utility to collect the performance data, and then feeding the data through custom-developed linkages to the Computer Associates' TELL-A-GRAF computer graphics software to generate the chart images for analysis by the system manager. The VMS ACCOUNTING utility is also utilized to gather interactive process information. The charts that are generated by VAXCMS are: 1) CPU modes for each node over the most recent four month period 2) CPU modes for the cluster as a whole using a weighted average of all the nodes in the cluster based on processing power 3) Percent of primary memory in use for each node over the most recent four month period 4) Interactive processes for all nodes over the most recent four month period 5) Daily, weekly, and monthly, performance summaries for CPU modes, percent of primary memory in use, and page fault rates for each node 6) Daily disk I/O performance data plotting Average Disk I/O Response Time based on I/O Operation Rate and Queue Length. VAXCMS is written in DCL and VAX FORTRAN for use with DEC VAX series computers running VMS 5.1 or later. This program requires the TELL-A-GRAF graphics package in order to generate plots of system data. A FORTRAN compiler is required. The standard distribution medium for VAXCMS is a 9-track 1600 BPI magnetic tape in DEC VAX BACKUP format. It is also available on a TK50 tape cartridge in DEC VAX BACKUP format. An electronic copy of the documentation in ASCII format is included on the distribution medium. Portions of this code are copyrighted by Mr. David Lavery and are distributed with his permission. These portions

  10. Deep formation waters of Western Europe, Russia and North America characterised by sodium, calcium, magnesium and chloride concentrations

    NASA Astrophysics Data System (ADS)

    Bozau, Elke; Hemme, Christina; Sattler, Carl-Diedrich; van Berk, Wolfgang

    2015-04-01

    Deep formation water can be classified according to depth, temperature, and salinity (e.g., Graf et al. 1966, Kharaka & Hanor 2007). Most of the deep formation waters contain dissolved solids in excess of sea water. The hydrogeochemical development of formation water has been discussed for a long time. It is widely accepted that deep aquifers are influenced by the meteoric cycle and geochemical processes within the crust (e.g., Hebig et al. 2012). Similar hydrogeochemical signatures are found in deep formation waters of all continents and can be explained by general geochemical processes within the deep reservoirs (e.g., Land 1995). Therefore, data of deep formation waters from Western Europe, Russia, and North America are collected and classified by the major water components. The data are used to identify important hydrogeochemical processes (e.g., halite dissolution and albitisation) leading to different compositions of formation water. Two significant water types are identified: Na-Cl water and Na-Ca-Cl water. Based on the collected hydrogeochemical data, development trends are stated for the formation waters, and albitisation is favoured as the main process for calcium enrichment. Furthermore, differences of formation water according to stratigraphical units are shown for deep reservoirs of the North German Basin and the North Sea. References: Graf, D.L., 1982. Chemical osmosis, reverse chemical osmosis, and the origin of subsurface brines. Geochimica Cosmochimica Acta 46, 1431-1448. Hebig, K.H., Ito, N., Scheytt, T., Marui, A., 2012. Review: Deep groundwater research with focus on Germany. Hydrogeology Journal 20, 227-243. Kharaka, Y.K., Hanor, J.S., 2007. Deep fluids in continents: I. Sedimentary Basins. Treatise on Geochemistry 5, 1-48. Land, L.S., 1995. The role of saline formation water in the crustal cycling. Aquatic Geochemistry 1, 137-145. Acknowledgements: The presented data are results of the collaborative research program "gebo" (Geothermal energy

  11. Acoustic and elastic multiple scattering and radiation from cylindrical structures

    NASA Astrophysics Data System (ADS)

    Amirkulova, Feruza Abdukadirovna

    Multiple scattering (MS) and radiation of waves by a system of scatterers is of great theoretical and practical importance and is required in a wide variety of physical contexts such as the implementation of "invisibility" cloaks, the effective parameter characterization, and the fabrication of dynamically tunable structures, etc. The dissertation develops fast, rapidly convergent iterative techniques to expedite the solution of MS problems. The formulation of MS problems reduces to a system of linear algebraic equations using Graf's theorem and separation of variables. The iterative techniques are developed using Neumann expansion and Block Toeplitz structure of the linear system; they are very general, and suitable for parallel computations and a large number of MS problems, i.e. acoustic, elastic, electromagnetic, etc., and used for the first time to solve MS problems. The theory is implemented in Matlab and FORTRAN, and the theoretical predictions are compared to computations obtained by COMSOL. To formulate the MS problem, the transition matrix is obtained by analyzing an acoustic and an elastic single scattering of incident waves by elastic isotropic and anisotropic solids. The mathematical model of wave scattering from multilayered cylindrical and spherical structures is developed by means of an exact solution of dynamic 3D elasticity theory. The recursive impedance matrix algorithm is derived for radially heterogeneous anisotropic solids. An explicit method for finding the impedance in piecewise uniform, transverse-isotropic material is proposed; the solution is compared to elasticity theory solutions involving Buchwald potentials. Furthermore, active exterior cloaking devices are modeled for acoustic and elastic media using multipole sources. A cloaking device can render an object invisible to some incident waves as seen by some external observer. The active cloak is generated by a discrete set of multipole sources that destructively interfere with an

  12. Decoding Target Distance and Saccade Amplitude from Population Activity in the Macaque Lateral Intraparietal Area (LIP)

    PubMed Central

    Bremmer, Frank; Kaminiarz, Andre; Klingenhoefer, Steffen; Churan, Jan

    2016-01-01

    Primates perform saccadic eye movements in order to bring the image of an interesting target onto the fovea. Compared to stationary targets, saccades toward moving targets are computationally more demanding since the oculomotor system must use speed and direction information about the target as well as knowledge about its own processing latency to program an adequate, predictive saccade vector. In monkeys, different brain regions have been implicated in the control of voluntary saccades, among them the lateral intraparietal area (LIP). Here we asked, if activity in area LIP reflects the distance between fovea and saccade target, or the amplitude of an upcoming saccade, or both. We recorded single unit activity in area LIP of two macaque monkeys. First, we determined for each neuron its preferred saccade direction. Then, monkeys performed visually guided saccades along the preferred direction toward either stationary or moving targets in pseudo-randomized order. LIP population activity allowed to decode both, the distance between fovea and saccade target as well as the size of an upcoming saccade. Previous work has shown comparable results for saccade direction (Graf and Andersen, 2014a,b). Hence, LIP population activity allows to predict any two-dimensional saccade vector. Functional equivalents of macaque area LIP have been identified in humans. Accordingly, our results provide further support for the concept of activity from area LIP as neural basis for the control of an oculomotor brain-machine interface.

  13. Prevalence of different hip sonographic types: A cross-sectional study

    PubMed Central

    Adibi, Atoosa; Karami, Mahdi; Koohi, Kaveh; Shirahmad, Mehran

    2015-01-01

    Background: Developmental dysplasia of the hip (DDH) is an anatomical abnormality, which needs early detection and treatment. Ultrasound (US) is a sensitive method to study neonatal hip joint and detection of different types of sonographic hip. This study was aimed to determine relative frequency of different types of DDH ultrasonographically. Materials and Methods: Ultrasound examination was performed on 380 newborns to determine hip joint status according to the Graf ultrasound classification system for infant hips. In addition, hip joint status was compared based on the hip side, gender, and method of delivery. Results: In this study, we observed three sonographic types: Ia (74%), type Ib (20%), and IIa (6%). No significant difference was found in relative frequency of different types of DDH regarding the side of the hip (P = 0.18). Type IIa was found significantly more in the female newborns (P < 0.0001) and in newborns who were born by cesarean section (P < 0.0001). Conclusion: This study supports the role of US detection of different types of DDH; however, the frequency of pathologic types of hip sonography is 6%. PMID:25709988

  14. A motor similarity effect in object memory.

    PubMed

    Downing-Doucet, Frédéric; Guérard, Katherine

    2014-08-01

    In line with theories of embodied cognition (e.g., Versace et al. European Journal of Cognitive Psychology, 21, 522-560, 2009), several studies have suggested that the motor system used to interact with objects in our environment is involved in object recognition (e.g., Helbig, Graf, & Kiefer Experimental Brain Research, 174, 221-228, 2006). However, the role of the motor system in immediate memory for objects is more controversial. The objective of the present study was to investigate the role of the motor system in object memory by manipulating the similarity between the actions associated to series of objects to be retained in memory. In Experiment 1, we showed that lists of objects associated to dissimilar actions were better recalled than lists associated to similar actions. We then showed that this effect was abolished when participants were required to perform a concurrent motor suppression task (Experiment 2) and when the objects to be memorized were unmanipulable (Experiment 3). The motor similarity effect provides evidence for the role of motor affordances in object memory.

  15. Pedicle screw-based posterior dynamic stabilizers for degenerative spine: in vitro biomechanical testing and clinical outcomes.

    PubMed

    Chamoli, Uphar; Diwan, Ashish D; Tsafnat, Naomi

    2014-09-01

    Dynamic stabilization in a degenerate symptomatic spine may be advantageous compared with conventional fusion procedures, as it helps preserve motion and minimizes redistribution of loads at instrumented and adjacent segments. This article presents a systematic review of biomechanical and clinical evidence available on some of the pedicle screw based posterior dynamic stabilization (PDS) devices. Using Medline, Embase, and Scopus online databases, we identified four pedicle-screw-PDS devices for which both, biomechanical testing and clinical follow-up data are available: Graf artificial ligaments, Isobar TTL, Polyetheretherketone rods, and Dynesys. The current state-of-the-art of pedicle-screw-PDS devices is far from achieving its desired biomechanical efficacy, which has resulted in a weak support for the posited clinical benefits. Although pedicle-screw-PDS devices are useful in salvaging a moderately degenerate functionally suboptimal disc, for severe disc degeneration cases fusion is still the preferred choice. We conclude that a pedicle-screw-PDS device should aim at restoring load sharing amongst spinal elements while preserving the qualitative and quantitative nature of spinal motion, especially minimize posterior shift of the helical axis of motion. More precise and objective assessment techniques need to be standardized for in vivo evaluation of intervertebral motion and load sharing amongst spinal elements across different pedicle-screw-PDS devices.

  16. Solution thermodynamics of poly(vinyl pyrrolidone) in ethanol/CCl{sub 4} mixtures

    SciTech Connect

    Schwager, F.; Marand, E.; Davis, R.M.

    1996-12-31

    The Gibbs free energy, the enthalpy, and the entropy of mixing of ethanol with the polymer polyvinylpyrrolidone, PVP, and with its low molecular weight analogue, N-ethylpyrrolidone, NEP were calculated. The calculation of the free energy of mixing was achieved with the thermodynamic model for hydrogen bonded polymer systems developed by Painter, Coleman, and Graf. This model, based on the use of an association model, gives the free energy of mixing as a function of the Flory-Huggins interaction parameter, the composition of the mixture, and the association equilibrium constants. The self-association of the ethanol molecules was described by two equilibrium constants, one for the formation of dimers and one for the formation of multimers. The equilibrium constants of inter-association of PVP or NEP with ethanol were determined from the quantitative analysis of NEP/ethanol and PVP/ethanol FTIR spectra at various temperatures and compositions. The values of the equilibrium constants were then used to calculate the theoretical Gibbs free energy of mixing as a function of the composition. The enthalpic and entropic contributions to mixing were compared for the NEP/ethanol and PVP/ethanol mixtures.

  17. New records for the Kosovo caddisfly fauna with the description of a new species, Drusus dardanicus sp. nov. (Trichoptera: Limnephilidae).

    PubMed

    Ibrahimi, Halil; Kučinić, Mladen; Vitecek, Simon; Waringer, Johann; Graf, Wolfram; Previšić, Ana; Bálint, Miklós; Keresztes, Lujza; Pauls, Steffen U

    2015-01-01

    The Balkan Peninsula is one of the most important European hotspots of freshwater biodiversity. The region is, however, to a large extent insufficiently investigated. Here we present data on distribution of caddisflies in one particularly understudied area, the Republic of Kosovo. Our data include the first records of Adicella altandroconia Botosaneanu & Novak and Halesus tessellatus (Rambur) for the Kosovo caddisfly fauna, and a new locality for the recently described Ecclisopteryx keroveci Previšić, Graf, & Vitecek. Further, we describe the new caddisfly species Drusus dardanicus sp. nov. from the Kopaonik Mountains. The new species belongs to the D. discophorus Species Group and differs morphologically from its most similar congeners (D. discophorus Radovanović, D. balcanicus Kumanski, and D. bureschi Kumanski) mainly in exhibiting (1) subtrianglar superior appendages; (2) a narrow, dorsal spinate area of tergite VIII; and (3) evenly rounded tips of intermediate appendages in caudal view. In phylogenetic analysis, D. dardanicus sp. nov. is well delineated and recovered as a sister taxon to D. osogovicus Kumanski, a species recorded from Bulgaria. The recent discovery of a new species and other rare or microendemic species presents important contributions to the knowledge on the rich freshwater biodiversity in Kosovo. These species face increasing anthropogenic pressure and threats to their conservation. PMID:26624385

  18. The Pathomechanics Of Calcaneal Gait

    NASA Astrophysics Data System (ADS)

    Sutherland, David H.; Cooper, Les

    1980-07-01

    The data acquisition system employed in our laboratory includes optical, electronic and computer subsystems. Three movie camera freeze the motion for analysis. The film is displayed on a motion analyzer, and the body segment positions are recorded in a three dimensional coordinate system with Graf/pen sonic digitizer. The angular rotations are calculated by computer and automatically plotted. The force plate provides measurements of vertical force, foreaft shear, medial-lateral shear, torque, and center of pressure. Electromyograms are superimposed upon gait movies to permit measurement of muscle phasic activity. The Hycam movie camera si-multaneously films (through separate lens) the subject and oscilloscope. Movement measurements, electromyograms, and floor reaction forces provide the data base for analysis. From a study of the gait changes in five normal subjects following tibial nerve block, and from additional studies of patients with paralysis of the ankle plantar flexors, the pathomechanics of calcaneal gait can be described. Inability to transfer weight to the forward part of the foot produces ankle instability and reduction of contralateral step length. Excessive drop of the center of mass necessitates com-pensatory increased lift energy output through the sound limb to restore the height of the center of mass. Excessive stance phase ankle dorsiflexion produces knee instability requiring prolonged quadriceps muscle phasic activity.

  19. Ground motions around a semi-circular valley partially filled with an inclined alluvial layer under SH-polarized excitation

    NASA Astrophysics Data System (ADS)

    Chang, Kao-Hao; Tsaur, Deng-How; Wang, Jeen-Hwa

    2014-12-01

    A simplified mathematical model, composed of a semi-circular valley partially filled with an inclined alluvial layer under plane SH-wave incidence, is presented. To evaluate the site response theoretically, a rigorous series solution is derived via the region-matching technique. For angular wavefunctions constrained by an inclined free surface, the original form of Graf's addition formula is recast to arbitrarily shift the local coordinate system. The valley geometry, filling material, angle of incidence, and wave frequency are taken as significant parameters in exploring the site effect on ground motions. Also included are the frequency- and time-domain computations. Two canonical cases, the semi-circular vacant canyon and the fully filled semi-circular alluvial valley, with exact analytical solutions, and the partly horizontally filled case previously studied, are taken to be particular cases of the proposed general model. Steady-state results show that the peak amplitudes of motion may increase at low frequencies when the filling layer inclines to the illuminated region. At low-grazing incidence, the phenomenon of wave focusing becomes evident on the shadow side of the filling layer. Transient-state simulations elucidate how a sequence of surface waves travel on the topmost alluvium along opposite directions and interfere with multiple reflected waves within the filling layer.

  20. Ground motions around a semicircular canyon with a dipping edge under SH plane wave incidence

    NASA Astrophysics Data System (ADS)

    Chang, Kao-Hao; Tsaur, Deng-How; Wang, Jeen-Hwa

    2016-01-01

    In order to explore the spatial distribution and temporal variation of ground motions near a semicircular canyon with a dipping edge, a simplified mathematical model is constructed. Based on the region-matching technique, a Fourier-Bessel series solution for the plane SH-wave excitation is derived and then applied to theoretically simulate the seismic response of the canyon. The use of the adequate wavefunctions and a newly derived Graf's addition formula can solve the unknown expansion coefficients. Parametric analyses with respect to the frequency of input motion, angle of incidence, and canyon geometry are illustrated. Both frequency- and time-domain computations are presented. The canonical case, a completed semicircular canyon, which has the exact analytical solution, and the horizontally truncated case analyzed in previous works are considered as particular cases of the proposed general model. Comparisons with boundary-element solutions show good agreement. Steady-state results show that the phenomenon of wave focusing tends to be significant when the incident angle bends toward the horizontal ground surface. Propagation and attenuation of scattered waves that originated from the surficial anomaly are exhibited in transient-state simulations.

  1. Bulk Magnetization in the Superconducting State of UPt3

    NASA Astrophysics Data System (ADS)

    Gannon, William; Halperin, William; Rastovski, Catherine; Eskildsen, Morten; Dai, Pengcheng; Stunault, Anne

    2013-03-01

    The unconventional superconductor UPt3 has long been thought to have an odd parity orbital, and triplet spin state. An important signature of such a state is the temperature independence of the spin susceptibility across the superconducting transition temperature. Here, we report bulk measurements of the susceptibility of UPt3 for magnetic fields along the crystal a-axis performed with polarized neutron diffraction. Temperature independence at all magnetic fields is observed, suggesting a spin triplet superconducting state for the entirety of the phase diagram, with equal spin pairs in the crystal basal plane. These results will be discussed in the context of existing theories for the superconducting state of this paradigm heavy fermion material [Graf et. al., PRB 62, 14393; Tsutsumi et. al., JPSJ 81, 074717 (2012)]. Support from US Department of Energy, Basic Energy Science, Division of Materials Science and Engineering awards DE-FG02-05ER46248, DE-FG02-10ER46783, and DE-FG02-05ER46202

  2. Response of a shallow asymmetric V-shaped canyon to antiplane elastic waves

    PubMed Central

    Chang, Kao-Hao; Tsaur, Deng-How; Wang, Jeen-Hwa

    2015-01-01

    This study focuses on the theoretical aspect of topographic scattering induced by a shallow asymmetric V-shaped canyon under plane shear horizontal-wave incidence. An analytical approach, based on the region-matching technique, is applied to derive a rigorous series solution, which is more general than that in a previous study. For the wave functions constrained in two angular directions, a novel form of Graf's addition formula is derived to arbitrarily shift the local coordinate system. Barrier geometry, angle of incidence and wave frequency are taken as the most significant parameters in exploring the topographic effects of localized concave free surfaces on ground motions. Both surface and subsurface motions are presented. Comparisons with previously published results and boundary-element solutions show good agreement. Frequency-domain results indicate that, for the high-frequency case at a low grazing angle (corresponding to the potential case in teleseismic propagation), the high levels of amplified motions occur mostly on the illuminated side of the canyon. When the windward slope is steeper, the peak amplitude values, at least 2.4 times larger than those of free-field responses, tend to increase. Time-domain simulations display how a sequence of scattered waves travel and attenuate at regional distances. PMID:25663801

  3. Space Station maintenance studies using plaid graphics

    NASA Technical Reports Server (NTRS)

    Helm, Mary E.

    1993-01-01

    The Graphics Analysis Facility (GRAF) has been used frequently to study extravehicular activity (EVA) maintenance scenarios on Space Station Freedom. The ability to use 3-dimensional visualization gives one a more accurate estimate of the Space Station environment. Moreover, human EVA and robotic kinematics can be accurately simulated for columetric reach and collision detection analysis. An animation of this kind was developed for a research group at JSC to study and discover problem areas involved with doing external Space Station maintenance tasks. On the EVA side, it was discovered that items such as handholds and temporary restraint mechanisms should more effectively facilitate EVA movement about the Space Station structure for the suited personnel. Issues concerning CETA cart configuration, PWP storage locations, and locations of EVA storage areas were also identified by use of the animation. In the area of EVA versus robotics, it was found that there is a strong desire to make EVA and robotics interfaces compatible on items such as replacement units and unpressurized logistics carriers. The animation also showed that the use of robotics within an EVA task increases the difficulty and duration of the task setup, leaving less time available for the maintenance task itself. Graphics animation provides a mechanism to simultaneously analyze several mission parameters (i.e., EVA reach, volumetric analysis, and task timelines), and thus, it has proven to be an effective method for mission evaluation.

  4. Recent Progress in Producing Lignin-Based Carbon Fibers for Functional Applications

    SciTech Connect

    Paul, Ryan; Burwell, Deanna; Dai, Xuliang; Naskar, Amit; Gallego, Nidia; Akato, Kokouvi

    2015-10-29

    Lignin, a biopolymer, has been investigated as a renewable and low-cost carbon fiber precursor since the 1960s. Although successful lab-scale production of lignin-based carbon fibers has been reported, there are currently not any commercial producers. This paper will highlight some of the known challenges with converting lignin-based precursors into carbon fiber, and the reported methods for purifying and modifying lignin to improve it as a precursor. Several of the challenges with lignin are related to its diversity in chemical structure and purity, depending on its biomass source (e.g. hardwood, softwood, grasses) and extraction method (e.g. organosolv, kraft). In order to make progress in this field, GrafTech and Oak Ridge National Laboratory are collaborating to develop lignin-based carbon fiber technology and to demonstrate it in functional applications, as part of a cooperative agreement with the DOE Advanced Manufacturing Office. The progress made to date with producing lignin-based carbon fiber for functional applications, as well as developing and qualifying a supply chain and value proposition, are also highlighted.

  5. New records for the Kosovo caddisfly fauna with the description of a new species, Drusus dardanicus sp. nov. (Trichoptera: Limnephilidae)

    PubMed Central

    Ibrahimi, Halil; Kučinić, Mladen; Vitecek, Simon; Waringer, Johann; Graf, Wolfram; Previšić, Ana; Bálint, Miklós; Keresztes, Lujza; Pauls, Steffen U.

    2016-01-01

    The Balkan Peninsula is one of the most important European hotspots of freshwater biodiversity. The region is, however, to a large extent insufficiently investigated. Here we present data on distribution of caddisflies in one particularly understudied area, the Republic of Kosovo. Our data include the first records of Adicella altandroconia Botosaneanu & Novak and Halesus tessellatus (Rambur) for the Kosovo caddisfly fauna, and a new locality for the recently described Ecclisopteryx keroveci Previšić, Graf, & Vitecek. Further, we describe the new caddisfly species Drusus dardanicus sp. nov. from the Kopaonik Mountains. The new species belongs to the D. discophorus Species Group and differs morphologically from its most similar congeners (D. discophorus Radovanović, D. balcanicus Kumanski, and D. bureschi Kumanski) mainly in exhibiting (1) subtrianglar superior appendages; (2) a narrow, dorsal spinate area of tergite VIII; and (3) evenly rounded tips of intermediate appendages in caudal view. In phylogenetic analysis, D. dardanicus sp. nov. is well delineated and recovered as a sister taxon to D. osogovicus Kumanski, a species recorded from Bulgaria. The recent discovery of a new species and other rare or microendemic species presents important contributions to the knowledge on the rich freshwater biodiversity in Kosovo. These species face increasing anthropogenic pressure and threats to their conservation. PMID:26624385

  6. DNA-based association and description of the larval stage of Apatania helvetica Schmid 1954 (Trichoptera, Apataniidae) with notes on ecology and zoogeography

    PubMed Central

    WARINGER, JOHANN; LUBINI, VERENA; HOPPELER, FELICITAS; PAULS, STEFFEN U.

    2016-01-01

    This paper describes the hitherto unknown larva of Apatania helvetica Schmid 1954. Sequence data from the mitochondrial cytochrome c oxidase region were used to associate adult females and larvae. Genetic data confirmed the autochthonous status of this taxon within the parthenogenetic Apatania muliebris complex (‘sous groupe’) sensu Schmid 1954. Information on the morphology of the larva is given, and the most important diagnostic features are illustrated. Apatania helvetica is morphologically close to Apatania muliebris McLachlan 1866 and A. fimbriata (Pictet 1834). In the context of Apataniidae, this trio of species can be separated by the presence of long tapering setae with flexuous tips at the anterior border of the pronotum, by a central gap within the transverse setal band on the 1st abdominal dorsum, by biometry of the frontoclypeal setation and by their distribution ranges in Europe. With respect to European ecoregions (Graf et al. 2008), Apatania muliebris has been recorded from the Alps, the central plains and highlands, the Baltic province, Great Britain, Ireland and Scandinavia; A. fimbriata is known from the Alps, the western and central highlands, the western plains, the Hungarian lowlands and the Carpathians. A. helvetica is restricted to the Alps and has only been recorded in Switzerland. PMID:26624099

  7. Decoding Target Distance and Saccade Amplitude from Population Activity in the Macaque Lateral Intraparietal Area (LIP)

    PubMed Central

    Bremmer, Frank; Kaminiarz, Andre; Klingenhoefer, Steffen; Churan, Jan

    2016-01-01

    Primates perform saccadic eye movements in order to bring the image of an interesting target onto the fovea. Compared to stationary targets, saccades toward moving targets are computationally more demanding since the oculomotor system must use speed and direction information about the target as well as knowledge about its own processing latency to program an adequate, predictive saccade vector. In monkeys, different brain regions have been implicated in the control of voluntary saccades, among them the lateral intraparietal area (LIP). Here we asked, if activity in area LIP reflects the distance between fovea and saccade target, or the amplitude of an upcoming saccade, or both. We recorded single unit activity in area LIP of two macaque monkeys. First, we determined for each neuron its preferred saccade direction. Then, monkeys performed visually guided saccades along the preferred direction toward either stationary or moving targets in pseudo-randomized order. LIP population activity allowed to decode both, the distance between fovea and saccade target as well as the size of an upcoming saccade. Previous work has shown comparable results for saccade direction (Graf and Andersen, 2014a,b). Hence, LIP population activity allows to predict any two-dimensional saccade vector. Functional equivalents of macaque area LIP have been identified in humans. Accordingly, our results provide further support for the concept of activity from area LIP as neural basis for the control of an oculomotor brain-machine interface. PMID:27630547

  8. Are consanguineous marriage and swaddling the risk factors of developmental dysplasia of the hip?

    PubMed

    Guner, Sukriye Ilkay; Guner, Savas; Peker, Erdal; Ceylan, Mehmet Fethi; Guler, Ayse; Turktas, Ugur; Kaki, Barıs

    2013-02-01

    The purpose of this study was to investigate prospectively the effects of swaddling and consanguineous marriage on developmental dysplasia of the hip and associated risk factors. We screened by ultrasound 265 infants using the Graf method. The Pediatrics Department referred all newborn infants with suspected instability or a recognized risk factor to the orthopedic clinic. Risk factors of developmental dysplasia of the hip were searched and noted in these patients. Swaddling and consanguineous marriage were also determined and noted. We observed 164 of 265 infants (61.9 %) who had been swaddled and that 64 of 265 infants' parents were in a consanguineous marriage (24.2 %). In the statistical analysis that was conducted for swaddling and consanguineous marriage, highly significant differences were found. Our study showed that the rate of developmental dysplasia of the hip is very high, 11.7 %, in our region, eastern Turkey. Also, we commonly see improper swaddling and consanguineous marriage in our region, which affects many infants.

  9. Visualization of a newborn's hip joint using 3D ultrasound and automatic image processing

    NASA Astrophysics Data System (ADS)

    Overhoff, Heinrich M.; Lazovic, Djordje; von Jan, Ute

    1999-05-01

    Graf's method is a successful procedure for the diagnostic screening of developmental dysplasia of the hip. In a defined 2-D ultrasound (US) scan, which virtually cuts the hip joint, landmarks are interactively identified to derive congruence indicators. As the indicators do not reflect the spatial joint structure, and the femoral head is not clearly visible in the US scan, here 3-D US is used to gain insight to the hip joint in its spatial form. Hip joints of newborns were free-hand scanned using a conventional ultrasound transducer and a localizer system fixed on the scanhead. To overcome examiner- dependent findings the landmarks were detected by automatic segmentation of the image volume. The landmark image volumes and an automatically determined virtual sphere approximating the femoral head were visualized color-coded on a computer screen. The visualization was found to be intuitive and to simplify the diagnostic substantially. By the visualization of the 3-D relations between acetabulum and femoral head the reliability of diagnostics is improved by finding the entire joint geometry.

  10. Computer-aided petrographic analysis of sandstones

    SciTech Connect

    Thayer, P.A.; Helmold, K.P.

    1987-05-01

    Thin-section point counting, mathematical and statistical analysis of petrographic-petrophysical data, report generation, and graphical presentation of results can be done efficiently by computer. Compositional and textural data are collected with a modified Schares point-counting system. The system uses an MS-DOS microcomputer programmed in BASIC to drive a motorized stage attached to a polarizing microscope. Numeric codes for up to 500 different categories of minerals, cements, pores, etc, are input using a separate keypad. Calculation and printing of constituent percentages, QFR, Folk name, and grain-size distribution are completed in seconds after data entry. Raw data files, compatible with software such as Lotus 1-2-3, SPSS, and SAS, are stored on floppy disk. Petrographic data files are transferred directly to a mainframe, merged with log and petrophysical data, analyzed statistically with SAS, and reports generated. SAS/GRAPH and TELL-A-GRAF routines linked with SAS generate a variety of cross plots, histograms, pie and bar charts, ternary diagrams, and vertical variation diagrams (e.g., depth vs. porosity, permeability, mean size, sorting, and percent grains-matrix-cement).

  11. Decoding Target Distance and Saccade Amplitude from Population Activity in the Macaque Lateral Intraparietal Area (LIP).

    PubMed

    Bremmer, Frank; Kaminiarz, Andre; Klingenhoefer, Steffen; Churan, Jan

    2016-01-01

    Primates perform saccadic eye movements in order to bring the image of an interesting target onto the fovea. Compared to stationary targets, saccades toward moving targets are computationally more demanding since the oculomotor system must use speed and direction information about the target as well as knowledge about its own processing latency to program an adequate, predictive saccade vector. In monkeys, different brain regions have been implicated in the control of voluntary saccades, among them the lateral intraparietal area (LIP). Here we asked, if activity in area LIP reflects the distance between fovea and saccade target, or the amplitude of an upcoming saccade, or both. We recorded single unit activity in area LIP of two macaque monkeys. First, we determined for each neuron its preferred saccade direction. Then, monkeys performed visually guided saccades along the preferred direction toward either stationary or moving targets in pseudo-randomized order. LIP population activity allowed to decode both, the distance between fovea and saccade target as well as the size of an upcoming saccade. Previous work has shown comparable results for saccade direction (Graf and Andersen, 2014a,b). Hence, LIP population activity allows to predict any two-dimensional saccade vector. Functional equivalents of macaque area LIP have been identified in humans. Accordingly, our results provide further support for the concept of activity from area LIP as neural basis for the control of an oculomotor brain-machine interface. PMID:27630547

  12. DNA-based association and description of the larval stage of Apatania helvetica Schmid 1954 (Trichoptera, Apataniidae) with notes on ecology and zoogeography.

    PubMed

    Waringer, Johann; Lubini, Verena; Hoppeler, Felicitas; Pauls, Steffen U

    2015-01-01

    This paper describes the hitherto unknown larva of Apatania helvetica Schmid 1954. Sequence data from the mitochondrial cytochrome c oxidase region were used to associate adult females and larvae. Genetic data confirmed the autochthonous status of this taxon within the parthenogenetic Apatania muliebris Complex ('sous groupe') sensu Schmid 1954. Information on the morphology of the larva is given, and the most important diagnostic features are illustrated. Apatania helvetica is morphologically close to Apatania muliebris McLachlan 1866 and A. fimbriata (Pictet 1834). In the context of Apataniidae, this trio of species can be separated by the presence of long tapering setae with flexible tips at the anterior border of the pronotum, by a central gap within the transverse setal band on the 1st abdominal dorsum, by biometry of the frontoclypeal setation and by their distribution in Europe. With respect to European ecoregions (Graf et al. 2008), Apatania muliebris has been recorded from the Alps, the central plains and highlands, the Baltic countries, Great Britain, Ireland and Scandinavia; A. fimbriata is known from the Alps, the western and central highlands, the western plains, the Hungarian lowlands and the Carpathians; and A. helvetica is restricted to the Alps and has been recorded only in Switzerland. PMID:26624099

  13. Effect of handedness on the Stroop Colour Word Task.

    PubMed

    Beratis, Ion N; Rabavilas, Andreas; Papadimitriou, George N; Papageorgiou, Charalabos

    2010-11-01

    Handedness is associated with cerebral organisation, but its relationship with cognition remains unclear. Since the Stroop task is believed to measure aspects of executive control, this study aims to investigate the effect of handedness on Stroop interference. We used the Stroop task with 90 young adults with university education, of whom 47 (23 males) were right-handed and 43 (21 males) were left-handed. Main dependent variables were Stroop baseline (SB), Stroop incongruent (SI), and the proportional derivative Stroop reduction (SR) [SR=(SB - SI)/SB×100%] (Bugg, Delosh, Davalos, & Davis, 2007; Graf, Uttl, &Tuokko, 1995) scores. The analysis revealed that SI is significantly affected by both handedness and the interaction of sex×handedness, whereas SR is only affected by handedness. After controlling for the effect of SB on SI, only the effect of handedness remained statistically significant [F(1, 83) = 6.44, p=.013]. Post-hoc comparisons showed that left-handed females performed significantly better than right-handed females on both SI (p=.003) and SR (p=.007). The data suggest that handedness is associated with cognitive function alterations, which lead to a smaller Stroop interference of left-handers irrespectively of sex, an effect that is more pronounced in the female subpopulation.

  14. DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

    SciTech Connect

    Elliot B. Kennel; R. Michael Bergen; Stephen P. Carpenter; Dady Dadyburjor; Manoj Katakdaunde; Liviu Magean; Alfred H. Stiller; W. Morgan Summers; John W. Zondlo

    2006-05-12

    The purpose of this DOE-funded effort is to develop continuous processes for solvent extraction of coal for the production of carbon products. The largest applications are those which support metals smelting, such as anodes for aluminum smelting and electrodes for arc furnaces. Other carbon products include materials used in creating fuels for the Direct Carbon Fuel Cell, metals smelting, especially in the aluminum and steel industries, as well as porous carbon structural material referred to as ''carbon foam'' and carbon fibers. During this reporting period, coking and composite fabrication continued using coal-derived samples. These samples were tested in direct carbon fuel cells. Methodology was refined for determining the aromatic character of hydro treated liquid, based on Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FTIR). Tests at GrafTech International showed that binder pitches produced using the WVU solvent extraction protocol can result in acceptable graphite electrodes for use in arc furnaces. These tests were made at the pilot scale.

  15. Subsurface Explosions in Granular Media

    NASA Astrophysics Data System (ADS)

    Lai, Shuyue; Houim, Ryan; Oran, Elaine

    2015-11-01

    Numerical simulations of coupled gas-granular flows are used to study properties of shock formation and propagation in media, such as sand or regolith on the moon, asteroids, or comets. The simulations were performed with a multidimensional fully compressible model, GRAF, which solves two sets of coupled Navier-Stokes equations, one for the gas and one for the granular medium. The specific case discussed here is for a subsurface explosion in a granular medium initiated by an equivalent of 200g of TNT in depths ranging from 0.1m to 3m. The background conditions of 100K, 10 Pa and loose initial particle volume fraction of 25% are consistent with an event on a comet. The initial blast creates a cavity as a granular shock expands outwards. Since the gas-phase shock propagates faster than the granular shock in loose, granular material, some gas and particles are ejected before the granular shock arrives. When the granular shock reaches the surface, a cap-like structure forms. This cap breaks and may fall back on the surface and in this process, relatively dense particle clusters form. At lower temperatures, the explosion timescales are increased and entrained particles are more densely packed.

  16. Finding structures with specific properties in complex configurational spaces using multi-target inverse band structure approach

    NASA Astrophysics Data System (ADS)

    Piquini, Paulo; Zunger, Alex

    2009-03-01

    The conventional strategy to look for materials with desired properties is to use physical intuition to select some candidates among an enormous number of possibilities.Apart the very special cases, the solutions to these search problems are far from obvious. The inverse band structure (IBS) approach, on the other hand, search for the desired electronic structures (instead of atomic configurations) from the beginning. Here we illustrate the power of this inverse approach by applying it to the simultaneous engineering of multi-target problems, which encompass huge configurational spaces: (i) the search of a specific band gap in the quaternary (In,Ga)(As,Sb) semiconductors(a) lattice-matched to InP and, (ii) the stacking sequence of (In,Ga)As/InP superlattices leading to band gaps and strains within the range suitable for thermophotovoltaic applications(b). [3pt] (a) P. Piquini, P.A. Graf, and A. Zunger, Phys. Rev. Lett. 100, 186403 (2008); [0pt] (b) P. Piquini and A. Zunger, Phys. Rev. B 78, 161302 (2008)

  17. Resonance scattering and radiation force calculations for an elastic cylinder using the translational addition theorem for cylindrical wave functions

    NASA Astrophysics Data System (ADS)

    Mitri, F. G.

    2015-09-01

    The standard Resonance Scattering Theory (RST) of plane waves is extended for the case of any two-dimensional (2D) arbitrarily-shaped monochromatic beam incident upon an elastic cylinder with arbitrary location using an exact methodology based on Graf's translational addition theorem for the cylindrical wave functions. The analysis is exact as it does not require numerical integration procedures. The formulation is valid for any cylinder of finite size and material that is immersed in a nonviscous fluid. Partial-wave series expansions (PWSEs) for the incident, internal and scattered linear pressure fields are derived, and the analysis is further extended to obtain generalized expressions for the on-axis and off-axis acoustic radiation force components. The wave-fields are expressed using generalized PWSEs involving the beam-shape coefficients (BSCs) and the scattering coefficients of the cylinder. The off-axial BSCs are expressed analytically in terms of an infinite PWSE with emphasis on the translational offset distance d. Numerical computations are considered for a zeroth-order quasi-Gaussian beam chosen as an example to illustrate the analysis. Acoustic resonance scattering directivity diagrams are calculated by subtracting an appropriate background from the expression of the scattered pressure field. In addition, computations for the radiation force exerted on an elastic cylinder centered on the axis of wave propagation of the beam, and shifted off-axially are analyzed and discussed.

  18. Sediment-induced buoyancy destruction and drag reduction in estuaries

    NASA Astrophysics Data System (ADS)

    Winterwerp, Johan C.; Lely, Marieke; He, Qing

    2009-11-01

    This paper presents an analysis of drag reduction by buoyancy destruction in sediment-laden open channel flow. We start from the log-linear profile proposed by Barenblatt (Prikladnaja Matematika i Mekhanika, 17:261-274, 1953), extended with a second length scale to account for free surface effects. Upon analytical integration over the water depth, an expression for sediment-induced drag reduction is found in terms of an effective Chézy number, water depth, bulk Richardson number, and Rouse number. This relation contains one empirical/experimental coefficient, which was obtained from a large series of numerical experiments with a 1DV point model. Upon calibration of this model against field and laboratory observations, we tuned the turbulent Prandtl-Schmidt number and found an optimal value of σ T = 2, consistent to observations by Cellino and Graf (ASCE, J Hydraulic Engineering, 125:456-462, 1999). All numerical results could be correlated with the simple relation C_{text{eff}} = C_0 + 4sqrt {g} hRi_{*} β , which is valid for fine sediment suspensions under conditions typical in open channel flow.

  19. Research Spotlight: The varying life expectancies of American reservoirs

    NASA Astrophysics Data System (ADS)

    Schultz, Colin

    2011-04-01

    Tasked with controlling floods, coping through droughts, generating electricity, maintaining the flow of drinking water, preserving species' habitats, and managing the local environment, the United States' large-scale freshwater management system is important. Unfortunately, as sediment is washed from river basins to reservoirs, the persistent addition of material eats away at a reservoir's capacity and, consequently, its useful life expectancy. Understanding the integrity of the reservoir system is particularly important, with climate projections anticipating warmer, drier conditions for some parts of the country. Using a database of sedimentation surveys conducted between 1775 and 1993, Graf et al. calculate the life expectancies of many of the nation's reservoirs. They find that although most of the country's large reservoirs were built between 1950 and 1960, they have a wide range of expiration dates. They find that most large reservoirs, those with capacities greater than 1.2 cubic kilometers (0.29 cubic mile), have useful life expectancies ranging from 200 to more than 1000 years, with the lowest average life expectancy in the interior West. (Water Resources Research, doi:10.1029/2009WR008836, 2010)

  20. Intermediate Phase in the Superconducting Cuprates.

    NASA Astrophysics Data System (ADS)

    Egami, Takeshi

    2007-03-01

    It has long been speculated that upon doping the Mott-Hubbard insulator may go through an intermediate phase before becoming a Fermi-liquid metal. If there is such a phase its structure may be intimately connected to the mechanism of the pseudogap and superconductivity. The only well-defined and popular option has been the spin-charge stripe phase, but the strongly one-dimensional nature of the stripe phase is at odds with the highly two-dimensional CuO2 plane. We propose a superlattice of 2√2 x2√2 in the a-b plane as an alternative candidate for the intermediate phase. In this phase the Mott-Hubbard states and the Fermi-liquid phase coexist in different Brillouin sub-zones. The presence of such a phase is consistent with the recent results of the ARPES at a high energy scale (J. Graf, et al., cond-mat/0607319), dispersion of Cu-O bond-stretching phonon mode in YBCO, pulsed neutron PDF analysis of LSCO, and our recent observation of the supperlattice peaks in YBa2Cu4O8 single crystal by x-ray diffraction. The intensity of the superlattice peaks in YBa2Cu4O8 decreases below 250K. This is an unusual behavior for the ordering peak, suggesting the interplay with superconductivity.

  1. Multiple Scattering of Dirac Fermions in Two Dimensions

    NASA Astrophysics Data System (ADS)

    Asmar, Mahmoud M.; Ulloa, Sergio E.

    2014-03-01

    The low energy dispersion of electrons in graphene-as well as surface states of three dimensional topological insulators- are characterized by a linear dispersion, leading to interesting dynamical properties. The presence of potential scattering centers, such as impurities in real samples or artificially created gated regions, also reflect the ``massless'' nature of electrons in these materials. The study of Dirac fermion scattering from single potential obstacles is made possible through partial wave methods. In the case of closely-spaced potential obstacles (high defect concentration), one should consider multiple scattering effects. Using separation of variables, Graf's addition rules, and far field matching, one can generalize the partial wave method to the case of many scatterers, and obtain physical observables for such problem. We present our study of the scattering problem of Dirac fermions from multiple potential obstacles, with focus on the two-center problem. We discuss the dependence of the differential cross section on the separation, and different potential shifts caused by these obstacles, and compare these results with the differential cross section for a single scattering center. We also study the minimal conditions that allow the observation of Klein tunneling. Supported by MWN/CIAM-NSF and AvH.

  2. Scattering of SH waves induced by a symmetrical V-shaped canyon: a unified analytical solution

    NASA Astrophysics Data System (ADS)

    Zhang, Ning; Gao, Yufeng; Li, Dayong; Wu, Yongxin; Zhang, Fei

    2012-12-01

    This paper reports a series solution of wave functions for two-dimensional scattering and diffraction of plane SH waves induced by a symmetrical V-shaped canyon with different shape ratios. A half-space with a symmetrical V-shaped canyon is divided into two sub-regions by using a circular-arc auxiliary boundary. The two sub-regions are represented by global and local cylindrical coordinate systems, respectively. In each coordinate system, the wave field satisfying the Helmholtz equation is represented by the separation of variables method, in terms of the series of both Bessel functions and Hankel functions with unknown complex coefficients. Then, the two wave fields are described in the local coordinate system using the Graf addition theorem. Finally, the unknown coefficients are sought by satisfying the continuity conditions of the auxiliary boundary. To consider the phase characteristics of the wave scattering, a parametric analysis is carried out in the time domain by assuming an incident signal of the Ricker type. Surface and subsurface transient responses demonstrate the characteristics and mechanisms of wave propagating and scattering.

  3. Nonlinearity modelling of an on-board microwave photonics system based on Mach-Zehnder modulator

    NASA Astrophysics Data System (ADS)

    Zhu, Zi-hang; Zhao, Shang-hong; Yao, Zhou-shi; Tan, Qing-gui; Li, Yong-jun; Chu, Xing-chun; Wang, Xiang; Zhao, Gu-hao

    2012-11-01

    For the nonlinearity distortion problem of Mach-Zehnder modulator (MZM) applied in the on-board microwave photonics system, the situation for two input radio frequency (RF) signals with different frequencies and phases is discussed, and an exact analytical solution is derived with the method of expanding Bessel series and Graf addition theory. According to the analytical expression, the nonlinearity characteristics of the modulator can be precisely predicted, and the system performance can be optimized. The correctness of the analytical solution is approved by simulation results. Analytical results indicate that the nonlinearity distortion is suppressed as the decrease of modulation index, the increase of direct current bias phase shift and phase difference between two input RF signals. When the phase difference equals zero or π and the direct current bias phase shift is π/2, there are only odd-order distortion terms. When the phase difference equals zero or π and the direct current bias phase shift is π, there are only even-order distortion terms.

  4. Velocity Profile Normalization of Field-Measured Turbidity Currents

    NASA Astrophysics Data System (ADS)

    Xu, J.

    2009-05-01

    Multiple occurrences of turbidity currents were observed in moored-ADCP measurements in Monterey (2002/03) and Hueneme (2007/08) submarine canyons, California. These turbidity currents, almost all of which were supercritical (densimetric Froude number greater than unity), lasted for hours and obtained a maximum speed of greater than 200 cm/s. The layer-averaged velocity of the turbidity currents varied from 100+ cm/s at the onset of the turbidity currents to 20+ cm/s toward the end of the events. The thickness of the turbidity currents tended to increase from 10 to 40 m over an event. Empirical functions, obtained from laboratory experiments whose spatial and time scales are two to three orders of magnitude smaller than the field measurements [e.g. Altinakar, Graf, and Hopfinger, 1996, Flow structure in turbidity currents, Journal of Hydraulic Research, 34(5):713-718], were found to represent the field data fairly well. However, the best similarity collapse of the turbidity current velocity profiles was obtained when the streamwise velocity was normalized by the layer-averaged velocity and the elevation was normalized by the turbidity current thickness. This normalization scheme can be generalized to the same empirical function y = exp (-α xm) for the jet region above the velocity maximum.

  5. Superconductivity close to a charge-density-wave instability

    NASA Astrophysics Data System (ADS)

    Bourbonnais, Claude; Bakrim, Hassan

    2010-03-01

    The recent discovery of superconductivity (SC) in proximity of a Peierls distorted phase in the perylene based organic conductor Per2Au(mnt)2 [1] has raised once again the issue about the role of charge-density-wave (CDW) correlations in the mechanism of Cooper pairing. We have applied the renormalization group approach to a quasi-1D model of electrons interacting with acoustic phonons modes and studied the interplay between the two instabilities. From the one-loop flow equations for the momentum and frequency dependent interactions induced by phonons we analyze the stability of CDW and SC states vs the phonon frequency φD and the hopping parameter t' for nesting alterations. S-wave SC is demonstrated to be stabilyzed above some critical t'^*. In these conditions, the superconducting Tc˜φD^η exibits a non-BCS power law increase with φD(η˜0.7), as a result of quantum interfering CDW and SC pairings. The complete phase diagram is obtained as a function of both t' and φD and shown to agree with the one found for Per2Au(mnt)2 under pressure [1]. [1] D. Graf et al., Eur. Phys. Lett. 85, 27009 (2009).

  6. High-energy dispersion anomalies in actinide compounds

    NASA Astrophysics Data System (ADS)

    Das, T.; Durakiewicz, T.; Zhu, J.-X.; Joyce, J. J.; Graf, Matthias J.

    2012-02-01

    The observation of a prominent peak-dip-hump feature in the spectral weight in number of actinide compounds including Pu-115 superconductors and non-superconducting U-115 remains an unsolved problem. We have developed a first-principles intermediate coupling model to show that most aspects of these strong correlation features can be understood from the spin-fluctuation interaction.[1] The results show that a strong peak in the spin-fluctuation dressed self-energy is present around 0.5 eV in all these materials, which is mostly created by spin-orbit split 5f bands. These fluctuations couple to the single-particle spectrum and give rise to a peak-dip-hump feature, characteristic of the coexistence of itinerant and localized electronic states. Results are in quantitative agreement with photoemission spectra. Finally, we show that the studied actinides can be understood within the rigid-band filling approach, in which the spin-fluctuation coupling constant follows the same materials dependence as the superconducting transition temperature Tc. Work is supported by US DOE. [4pt] [1] T. Das. J.-X. Zhu, and M. J. Graf, arXiv:1108.0272

  7. Streamerless Guided Electric Discharges Triggered by Femtosecond Laser Filaments

    NASA Astrophysics Data System (ADS)

    Gordon, Daniel; Ting, Antonio; Hubbard, Richard; Briscoe, Eldridge; Jones, Theodore; Manka, Charles; Slinker, Steven; Baronavski, A. P.; Ladouceur, H. D.; Grounds, P. W.; Girardi, P. G.

    2003-10-01

    The time evolution of electrical discharges induced and guided between the cathode of a 200 kV Van de Graf generator and a ground sphere was studied using a 100 fs Ti:Sapphire laser. Nonlinear focusing and ionization effects produce optical and plasma filaments in the discharge region. Streak camera images often exhibit streamers that propagate towards the cathode, but sudden discharge triggering is frequently observed with no streamer precursors. The typical discharge triggering delay time was measured to be 150 ns. Similar time delays were obtained from an air chemistry code used to model the long time behavior of the plasma induced by the short laser pulse. The model shows that ohmic heating of the filament plasma persists over long time scales and inhibits the decay of electron density due to recombination and attachment processes. Eventually the rise in electron temperature causes the avalanche rate to increase to the point where breakdown occurs. The hydrodynamic density reduction process reported by Tzortzakis, et al. [Phys. Rev E 64, 057401, 2001] is also taken into consideration. Its main effect is found to be a hastening of the breakdown process.

  8. Streamerless guided electric discharges triggered by femtosecond laser filaments

    NASA Astrophysics Data System (ADS)

    Gordon, D. F.; Ting, A.; Hubbard, R. F.; Briscoe, E.; Manka, C.; Slinker, S. P.; Baronavski, A. P.; Ladouceur, H. D.; Grounds, P. W.; Girardi, P. G.

    2003-11-01

    The time evolution of electrical discharges induced and guided between the cathode of a Van de Graf generator and a ground sphere was studied using a 100 fs Ti:Sapphire laser. Nonlinear focusing and ionization effects produce optical and plasma filaments in the discharge region. Streak camera images often exhibit streamers that propagate towards the cathode, but sudden discharge triggering is frequently observed with no streamer precursors. The typical discharge triggering delay time was measured to be 150 ns. Similar time delays were obtained from an air chemistry code used to model the long time behavior of the plasma induced by the short laser pulse. The model shows that ohmic heating of the filament plasma persists over long time scales and inhibits the decay of electron density due to recombination and attachment processes. Eventually the rise in electron temperature causes the avalanche rate to increase to the point where breakdown occurs. The hydrodynamic density reduction process reported by Tzortzakis et al. [Phys. Rev. E 64, 057401 (2001)] is also taken into consideration. Its main effect is found to be a hastening of the breakdown process.

  9. Measurement of 26Al in Iron Meteorites by Thermal Ionization Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Langellier, C.; Birck, J. L.; Allegre, C. J.

    1992-07-01

    We report here the measurement of ^26Al by thermal ionization mass spectrometry in iron meteorites. Nuclides produced by the interaction of galactic cosmic rays with meteoritic bodies are widely used to reconstruct the parental history of meteorites and also to address the problem of constancy of cosmic rays in the past. In iron meteorites the half life of ^26Al is much shorter than the exposure age and saturation is reached. Its concentration is then directly related to the preatmospheric shielding of the analyzed sample. It can be also used together, with other short-lived nuclides, to calculate the terrestrial residence time for found meteorites. Natural contents of ^26Al in iron meteorites are very small (a few dpm per kg) and have been measured earlier by counting techniques and AMS. For thermal ionization the difficulty resides mostly in the measurement of the ^26Al/^27Al ratio. ^27Al may be contained in the sample and also is introduced by the chemical separation. ^27Al beams of 10^-11 A are readily obtained with a few ng of aluminium and are measured on a standard faraday cup. ^26Al was measured on a low background electron multiplier operated in the ion counter mode. ^27Al content was measured by isotope dilution using a ^26Al spike. The ^26Al ion beam can be interfered by traces of ^26Mg. Usually the ^26Mg background could be brought lower than 10^-9 relative to ^27Al. This is sufficient for the present experiment. No organic interference was present at the same level. The abundance sensitivity stemming from the ^27Al beam on mass 26 is 3 10^-9. Results: Samples sizes for this study range from 100 to 300 mg of iron. Ratios are measured with a precision of about 1% thereby leading to a final ^26Al content with an accuracy around 2%. Two meteorites were investigated so far: Grant and Canyon Diablo. Grant is one of the best documented meteorites with regard to spallation effects. The result on Grant is an agreement with literature AMS data (Graf et al., 1987

  10. Effects of drought and irrigation on ecosystem functioning in a mature Scots pine forest

    NASA Astrophysics Data System (ADS)

    Dobbertin, Matthias; Brunner, Ivano; Egli, Simon; Eilmann, Britta; Graf Pannatier, Eisabeth; Schleppi, Patrick; Zingg, Andreas; Rigling, Andreas

    2010-05-01

    . Soil water content was significantly reduced during irrigation periods. Irrigation doubled tree stem growth, increased shoot growth and thus increased volume growth and crown dimensions. Annual tree mortality rates were reduced by 50% in irrigated plots. The growing period for stem growth was extended in pines as a result of irrigation. Altogether, increased growth and reduced mortality significantly increased tree stem basal area at breast height per ha. As irrigation also increased needle length, estimated mean foliage amount per tree and stand leaf area index significantly increased. However, the number of needle generations was not altered or even reduced due to irrigation. Root growth, was less affected by irrigation and only resulted in increased fine root length. Species richness and fruit body numbers of mycorrhizal fungi were several times higher on the irrigated plots. Overall, it can be concluded that water availability was the main ecosystem limiting factor and that any changes in water availability will result in changes in ecosystem functioning. References Brunner I, Graf-Pannatier E, Frey B, Rigling A, Landolt W, Dobbertin M (2009) Morphological and physiological responses of Scots pine fine roots to water supply in a climatic dry area in Switzerland. Tree Physiology 29:541-550. Dobbertin M, Eilmann B, Bleuler P, Giuggiola A, Graf Pannatier E, Landolt W, Schleppi P, Rigling A (2010) Effect of irrigation on needle, shoot and stem growth in natural drought-exposed Pinus sylvestris forests, Tree Physiology, doi:10.1093/treephys/tpp123. Eilmann B, Zweifel R, Buchmann N, Fonti P, Rigling A (2009) Drought induced adaptation of the xylem in Pinus sylvestris and Quercus pubescens. Tree Physiology 29:1011-1020.

  11. Linking soil permeability and soil aggregate stability with root development: a pots experiment (preliminary results)

    NASA Astrophysics Data System (ADS)

    Vergani, Chiara; Graf, Frank; Gerber, Werner

    2015-04-01

    Quantifying and monitoring the contribution of vegetation to the stability of the slopes is a key issue for implementing effective soil bioengineering measures. This topic is being widely investigated both from the hydrological and mechanical point of view. Nevertheless, due to the high variability of the biological components, we are still far from a comprehensive understanding of the role of plants in slope stabilization, especially if the different succession phases and the temporal development of vegetation is considered. Graf et al., 2014, found within the scope of aggregate stability investigations that the root length per soil volume of alder specimen grown for 20 weeks under laboratory conditions is comparable to the one of 20 years old vegetation in the field. This means that already relatively short time scales can provide meaningful information at least for the first stage of colonization of soil bioengineering measures, which is also the most critical. In the present study we analyzed the effect of root growth on two soil properties critical to evaluate the performance of vegetation in restoring and re-stabilizing slopes: permeability and soil aggregate stability. We set up a laboratory experiment in order to work under controlled conditions and limit as much as possible the natural variability. Alnus incana was selected as the study species as it is widely used in restoration projects in the Alps, also because of its capacity to fix nitrogen and its symbiosis with both ecto and arbuscular mycorrhizal fungi. After the first month of growth in germination pots, we planted one specimen each in big quasi cylindrical pots of 34 cm diameter and 35 cm height. The pots were filled with the soil fraction smaller than 10 mm coming from an oven dried moraine collected in a subalpine landslide area (Hexenrübi catchment, central Switzerland). The targeted dry unit weight was 16 kN/m3. The plants have been maintained at a daily temperature of 25°C and relative

  12. The human role in changing river channels

    NASA Astrophysics Data System (ADS)

    Gregory, K. J.

    2006-09-01

    Direct consequences of the human role, where human activity affects river channels through engineering works including channelization, dam construction, diversion and culverting, have been long recognised [Marsh, G.P., 1864. Man and Nature or Physical Geography as Modified by Human Action. Charles Scribner, New York; Thomas Jr., W.L., (ed.) 1956. Man's Role in Changing the Face of the Earth. Chicago, University of Chicago Press, Chicago.]. The less obvious indirect effects of point and reach changes occurring downstream and throughout the basin, however, are much more recently appreciated, dating from key contributions by Strahler [Strahler, A.N., 1956. The nature of induced erosion and aggradation. In W. L. Thomas (Ed.), Man's Role in Changing the Face of the Earth. University of Chicago Press, Chicago, 621-638.], Wolman [Wolman, M.G., 1967. A cycle of sedimentation and erosion in urban river channels. Geografiska Annaler 49A, 385-95.], Schumm [Schumm, S.A., 1969. River metamorphosis. Proceedings American Society of Civil Engineers, Journal Hydraulics Division 95, 255-73.], and Graf [Graf, W.L., 1977. The rate law in fluvial geomorphology. American Journal of Science, 277, 178-191.]. These are complemented by effects of alterations of land use, such as deforestation, intensive agriculture and incidence of fire, with the most extreme effects produced by building activity and urbanisation. Changing river channels are most evident in the channel cross-section where changes of size, shape and composition are now well-established, with up to tenfold increases or decreases illustrated by results from more than 200 world studies. In addition the overall channel planform, the network and the ecology have changed. Specific terms have become associated with changing river channels including enlargement, shrinkage and metamorphosis. Although the scope of adjustment has been established, it has not always been possible to predict what will happen in a particular location

  13. 36Cl-36Ar Exposure Ages of Chondritic Metals

    NASA Astrophysics Data System (ADS)

    Graf, Th.; Caffee, M. W.; Finkel, R. C.; Marti, K.; Nishiizumi, K.; Ponganis, K. V.

    1995-09-01

    shielding conditions and, since He, Ne and Ar production rates are essentially based on the ^81Kr (2.1 Ma) radionuclide, can also not be due to a change in the cosmic ray flux. A cross-calibration with the ^36Cl-^36Ar results may provide a means to further refine the exposure age histograms of meteorites. Acknowledgments: This work was supported by IGPP-LLNL and by NASA. References: [1] Graf Th. et al. (1995) LPS XXVI, 487-488. [2] Graf Th. and Marti K. (1995) JGR Planets, submitted. [3] Schultz L. et al. (1990) 17th Intl. Conf. Cosmochron. Isotope Geol. Fig. 1: Distribution of cosmic-ray produced ^3He/^38Ar in metal separates of H4 p.m. falls and H5 a.m. falls. The production rate ratio of ^3He/^38Ar in metal (16 +/- 2) is quite constant over a wide range of shielding conditions. Therefore, the bimodal distribution indicates an almost complete loss of ^3H as opposed to loss of ^3He.

  14. The influence of different El Nino types on the northern hemisphere stratosphere simulated by the MPI-ESM

    NASA Astrophysics Data System (ADS)

    Bittner, Matthias; Timmreck, Claudia; Schmidt, Hauke

    2013-04-01

    It is known that the El Nino Southern Oscillation (ENSO), although it is mainly a tropospheric phenomenon, has an impact on the polar winter stratosphere [e.g. van Loon and Labitzke, 1987: Camp and Tung, 2007]. This has also been shown in simulations with general circulation models (GCM) [Sassi,et al. 2004, Manzini et al. 2006]. For a couple of years there are discussions about two different "flavors" of the the El Nino, the central Pacific (or Modoki) El Nino and the east Pacific El Nino [e.g. Wang and Weisberg, 2000; Yu and Kao, 2007; Ashok et al. 2007]. An observational study [Graf and Zanchettin, 2012] indicate that the polar vortex is more disturbed during EP El Ninos. Here we to investigate the influence of the equatorial sea surface temperatures on the stratosphere-troposphere coupling in the northern hemisphere winter season in a fully coupled atmosphere-ocean-land GCM. We use two versions of the Max-Planck-Institute for Meteorology model MPI-ESM, namely MPI-ESM-LR with lower T63 L47 atmosphere and GR15 ocean resolution and the MPI-ESM-MR with the same horizontal resolution in the atmosphere but a higher resolution in the vertical (L95) and in the ocean (TP04). To exclude effects of natural and anthropogenic forcing, we analyze a 1000 year coupled control simulation with pre-industrial greenhouse gas concentration and constant solar forcing (piControl). For comparison with reananlyis data we also analyze uncoupled atmosphere-only simulations with observed sea surface temperatures from 1979 until 2008 (AMIP). We compare three ways of defining El Nino: the central Pacific (CP), the east Pacific (EP) and the canonical Nino3.4 El Nino. We show to what extent the MPI-ESM is able to simulate these different types of El Nino and how they affect the polar stratosphere. The MPI-ESM model is in both versions capable of producing CP and EP El Ninos. However, the CP El Nino is dominant one in terms of magnitude and the EP El Nino has a relative small impact on global

  15. Cosmogenic 10Be and Noble Gases in Diogenites

    NASA Astrophysics Data System (ADS)

    Welten, K. C.; Lindner, L.; van der Borg, K.; Loeken, Th.; Scherer, P.; Schultz, L.

    1993-07-01

    for different populations on the basis of their exposure histories. Figure 1 shows the experimental relation between 10Be contents and 22Ne/21Ne ratios measured in diogenites. The 10Be contents decrease by 30-35%, while corresponding 22Ne/21Ne ratios increase from 1.07 to 1.29. Graf's semi- experimental model predicts--for L chondrites with preatmospheric radii less than 50 cm--a decrease of about 50% in 10Be over this interval of 22Ne/21Ne ratios [7]. This discrepancy cannot be explained by the minor differences in composition with respect to 10Be production. Therefore, our results indicate that this model is slightly overestimating the shielding sensitivity of 10Be. Five points do not fall within 2 sigma on the best (exponential) fit. Measurements of additional radionuclides may contribute to a better understanding of their outlying character. Acknowledgments: We thank the MWG in the USA, the NIPR in Tokyo and the National Museums for Natural History in Washington, London, and Paris for diogenite samples. This work was financially supported by the Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO). References: [1] Welten K. C. et al. (1991) Meteoritics, 26, 408. [2] Schultz L. (1987) LPSC XVIII, 884-885. [3] Alymer D. et al. (1988) GCA, 52, 1691-1698. [4] Schultz L. and Kruse H. (1989) Meteoritics, 24, 155-172. [5] Takeda H. (1991) GCA, 55, 35-57. [6] Berkley J. L. and Boynton N. J. (1992) Meteoritics, 27, 387-394. [7] Graf Th. et al. (1990) GCA, 54, 2521-2534. Figure 1, which appears in the hard copy, shows shielding effects on P10 in diogenites.

  16. From Greenhouse to Icehouse: Evidence of Climatic Changes Across the Marine Eocene-Oligocene Transition From the Massignano GSSP Section (Central Italy)

    NASA Astrophysics Data System (ADS)

    Coccioni, R.; Marsili, A.; Montanari, A.

    2004-12-01

    ., 2003), oxygen and carbon isotopes (Bodeselitsch et al., 2004), and environmental magnetism (Jovane et al., 2004) provide evidence of a major cooling trend with warm pulses. These pulses seems to be global in extent and may have been triggered by multiple impact events during the Late Eocene comet shower that may have played an important role related to the deterioration of the global climate at the end of the Eocene Epoch. The release of methane hydrate during and after an impact in a continental shelf (like the Chesapeake Bay impact) or seafloor, or impacts of 12C-rich comets may account for the observed negative isotope excursions. References Bice D. and Montanari A., 1988. IUGS Spec. Publ., Graf. Aniballi, 111-117; Bodeselitsch B. et al., 2004. E.P.S.L., 223, 283-302; Brinkhuis H. and Biffi U., 1993. Mar. Mic., 22, 131-183; Coccioni R. et al., 2000. Terra Nova, 12, 258-263; Coccioni R. and Galeotti S., 2003. In: Prothero D.R. et al., (eds.), 2003. Columbia Univ. Press, 438-452; Dall'Antonia B. et al., 2003. Mar. Mic., 48, 91-106; Farley K.A. et al., 1998. Science, 280, 1250-1253; Jovane L. et al., 2004. Geoph. Res. Let., 31, L15601, doi:10.1029/2004GL020554; Lowrie W. and Lanci L., 1994. E.P.S.L., 126, 247-258; Montanari A. et al., 1993. Palaios, 8, 420-437; Montanari A. et al., 1988. IUGS Spec. Publ., Graf. Aniballi, 195-208; Premoli Silva I. and Jenkins D.G., 1993. Episodes, 16, 379-382; Prothero D.R. et al., (eds.), 2003. Columbia Univ. Press, 541 pp.; Spezzaferri S. et al., 2002. J. Foram. Res., 32, 188-199.

  17. Is prematurity a risk factor for developmental dysplasia of the hip? : a prospective study.

    PubMed

    Orak, M M; Onay, T; Gümüştaş, S A; Gürsoy, T; Muratlí, H H

    2015-05-01

    The aim of this prospective study was to investigate prematurity as a risk factor for developmental dysplasia of the hip (DDH). The hips of 221 infants (88 female, 133 male, mean age 31.11 weeks; standard deviation (sd) 2.51) who were born in the 34th week of gestation or earlier, and those of 246 infants (118 female, 128 male, mean age 40.22 weeks; sd 0.36) who were born in the 40th week of gestation, none of whom had risk factors for DDH, were compared using physical examination and ultrasound according to the technique of Graf, within one week, after the correction of gestational age to the 40th week after birth or one week since birth, respectively. Both hips of all infants were included in the study. Ortolani's and Barlow's tests and restricted abduction were accepted as positive findings on examination. There was a statistically significant difference between pre- and full-term infants, according to the incidence of mature and immature hips (p < 0.001). The difference in the proportion of infants with an α angle < 60° between the two groups was statistically significant (p < 0.001). The incidence of pathological dysplasia (α angle < 50 º) was not significantly different in the two groups (p = 1.000). The Barlow sign was present in two (0.5%) pre-term infants and in 14 (2.8%) full-term infants. These results suggests that prematurity is not a predisposing factor for DDH. PMID:25922469

  18. The influence of lupin seed germination on the chemical composition and standardized ileal digestibility of protein and amino acids in pigs.

    PubMed

    Chilomer, K; Kasprowicz-Potocka, M; Gulewicz, P; Frankiewicz, A

    2013-08-01

    The germination process can modify the chemical composition of nutrients in seeds, which can influence the digestibility and utilization of sprouts in animal diets compared to raw seeds. The aims of research were to provide controlled germination process of lupin seeds, monitor the changes in seed composition and determine the influence of the germination on the coefficients of standardized ileal digestibility (SID) of crude protein and amino acids in growing pigs, compared to raw lupin seeds. The seeds of two lupin species were used: yellow (RYL) (Lupinus luteus, cv. Lord) and blue (RBL) (Lupinus angustifolius, cv. Graf). Germination was provided in the dark at 24°C for 4 days. Nutritional and antinutritional compositions of raw and germinated seeds (GYL and GBL, respectively) were analysed. Digestibility study was performed on pigs with an average body weight of 25 kg, and the pigs were surgically fitted with a T-cannula in the distal ileum, with chromic oxide as an indicator. Seed germination increased the crude protein and fibre concentrations, but reduced the levels of the ether extract, nitrogen-free extracts and all amino acids in protein. The content of alkaloids and raffinose family oligosaccharides decreased in both lupin species. Germination had no positive impact (p>0.05) on the SID of crude protein and amino acids. Germination of lupin seeds negatively influenced the SID of lysine and methionine (p<0.05). The results of the research revealed a decrease in the concentrations of antinutritional factors in the sprouts of yellow and blue lupins compared to raw seeds; however, no positive effect was observed on the coefficients of the standardized ileal apparent digestibility of protein and amino acids.

  19. [Impact of an |A|B|S|-training initiative on |A|B|S|-structural quality of participating hospitals].

    PubMed

    Christoph, Anna; Ehm, Christine; de With, Katja

    2015-01-01

    The "ABS-training initiative" was funded by the German Ministry of Health as part of the German Antimicrobial Resistance Strategy (Deutsche Antibiotika-Resistenz-Strategie, DART) from 2009 until early 2014. The initiative was designed for clinicians and clinical pharmacists and contains several training units covering antiinfectives, infectious diseases and ABS strategies including the conduction of a research project at the participants' hospital. Participants who complete the four-weeks training initiative will become a certified "ABS Expert". 281 ABS Experts were asked to take part in a survey (staff for ABS, surveillance data about agents and consumption, ABS activity) to estimate the influence of the ABS-training initiative on the ABS-structural quality. The evaluation was performed using GrafStat (V 4.255), statistical software package for the evaluation of surveys. Ninety-two ABS Experts representing 92 hospitals participated in a questionnaire-based survey before and after completing the training initiative. Forty (44 %) hospitals appointed an ABS representative (+22 %) after completing the training initiative. Antibiotic surveillance data available as a report increased from 34 (40 %) to 54 (60 %) and correct data presentation (DDD or RDD/100 days) from 7 (8 %) to 40 (43 %). Proactive auditing of antiinfective prescribing improved from 54 (60 %) to 71 (78 %) in intensive care units, and from 28 (31 %) to 53 (58 %) on normal wards. Availability of local guidelines increased from 36 (39 %) to 52 (57 %). The "ABS Training Initiative" had a positive impact on ABS-structural quality regarding nomination of ABS-teams, surveillance data of antibiotic consumption, implementation of proactive auditing of antiinfective prescribing and availability of local guidelines. However, there is optimization potential in many sectors. The short time period between pre- and post-assessment and the ongoing personnel or time constraints need to be taken into account.

  20. Soil aggregates in a collapsed chestnut grove and in an instable vineyard in Tuscany

    NASA Astrophysics Data System (ADS)

    Guastini, Enrico; Dani, Andrea

    2014-05-01

    Just like in agriculture the presence of stable macroaggregates is simptom of soil fecundity, in forestry the presence of stabe aggregates is index of stability for both the soil and the living communities settling there. Such formations, ascribable to organic matter and humic compound degree, can be present in better measure in a collapsed and recolonized soil than in non fallen area grown with the same species for long time. The mean stability in aggregates comes out to be very lower in farmed soil, yet foreseen by Tisdall and Oades (2006) wich wrote that farming generates a decline in the organic content of soil. The higher instability shown in the deepest soil, where the biotic contribution is lesser, and the higher infiltration found in superficial layers are in line with the empiric verification that the slip plane in shallow landslides doesn't intersect rhizosphere, but lays under it; the fragility zone is located where the organic matter degree is lower, both in humus and root and fungi exudates, or organism parts or remains. In other words, not only deep roots could sometimes anchor the shallow soil to the bedrock, but they can also improve the strenght characteristics of soil in presence of water. In soil with aggregates, moreover, seems to recognise an improvement in the shear strenght angle, accordingly with the results obtained by Graf et al. (2009) with triaxial tests on rooted soil samples. Roughly, the angle increase by 1 degree for every 5-7% in stable aggregates on the sample weigth, validating the better stability of a slope with a stable and mature community.

  1. Characterization of Porosity Development in Oxidized Graphite using Automated Image Analysis Techniques

    SciTech Connect

    Contescu, Cristian I; Burchell, Timothy D

    2009-09-01

    This document reports on initial activities at ORNL aimed at quantitative characterization of porosity development in oxidized graphite specimens using automated image analysis (AIA) techniques. A series of cylindrical shape specimens were machined from nuclear-grade graphite (type PCEA, from GrafTech International). The specimens were oxidized in air to various levels of weight loss (between 5 and 20 %) and at three oxidation temperatures (between 600 and 750 oC). The procedure used for specimen preparation and oxidation was based on ASTM D-7542-09. Oxidized specimens were sectioned, resin-mounted and polished for optical microscopy examination. Mosaic pictures of rectangular stripes (25 mm x 0.4 mm) along a diameter of sectioned specimens were recorded. A commercial software (ImagePro) was evaluated for automated analysis of images. Because oxidized zones in graphite are less reflective in visible light than the pristine, unoxidized material, the microstructural changes induced by oxidation can easily be identified and analyzed. Oxidation at low temperatures contributes to development of numerous fine pores (< 100 m2) distributed more or less uniformly over a certain depth (5-6 mm) from the surface of graphite specimens, while causing no apparent external damage to the specimens. In contrast, oxidation at high temperatures causes dimensional changes and substantial surface damage within a narrow band (< 1 mm) near the exposed graphite surface, but leaves the interior of specimens with little or no changes in the pore structure. Based on these results it appears that weakening and degradation of mechanical properties of graphite materials produced by uniform oxidation at low temperatures is related to the massive development of fine pores in the oxidized zone. It was demonstrated that optical microscopy enhanced by AIA techniques allows accurate determination of oxidant penetration depth and of distribution of porosity in oxidized graphite materials.

  2. CD151-α3β1 integrin complexes are prognostic markers of glioblastoma and cooperate with EGFR to drive tumor cell motility and invasion.

    PubMed

    Zhou, Pengcheng; Erfani, Sonia; Liu, Zeyi; Jia, Changhe; Chen, Yecang; Xu, Bingwei; Deng, Xinyu; Alfáro, Jose E; Chen, Li; Napier, Dana; Lu, Michael; Huang, Jian-An; Liu, Chunming; Thibault, Olivier; Segal, Rosalind; Zhou, Binhua P; Kyprianou, Natasha; Horbinski, Craig; Yang, Xiuwei H

    2015-10-01

    Glioblastoma, one of the most aggressive forms of brain cancer, is featured by high tumor cell motility and invasiveness, which not only fuel tumor infiltration, but also enable escape from surgical or other clinical interventions. Thus, better understanding of how these malignant traits are controlled will be key to the discovery of novel biomarkers and therapies against this deadly disease. Tetraspanin CD151 and its associated α3β1 integrin have been implicated in facilitating tumor progression across multiple cancer types. How these adhesion molecules are involved in the progression of glioblastoma, however, remains largely unclear. Here, we examined an in-house tissue microarray-based cohort of 96 patient biopsies and TCGA dataset to evaluate the clinical significance of CD151 and α3β1 integrin. Functional and signaling analyses were also conducted to understand how these molecules promote the aggressiveness of glioblastoma at molecular and cellular levels. Results from our analyses showed that CD151 and α3 integrin were significantly elevated in glioblastomas at both protein and mRNA levels, and exhibited strong inverse correlation with patient survival (p < 0.006). These adhesion molecules also formed tight protein complexes and synergized with EGF/EGFR to accelerate tumor cell motility and invasion. Furthermore, disruption of such complexes enhanced the survival of tumor-bearing mice in a xenograft model, and impaired activation of FAK and small GTPases. Also, knockdown- or pharmacological agent-based attenuation of EGFR, FAK or Graf (ARHGAP26)/small GTPase-mediated pathways markedly mitigated the aggressiveness of glioblastoma cells. Collectively, our findings provide clinical, molecular and cellular evidence of CD151-α3β1 integrin complexes as promising prognostic biomarkers and therapeutic targets for glioblastoma. PMID:26377974

  3. Clinical evaluation of ultrasound screening in follow-up visits of infants with cerebral palsy at high risk for developmental dysplasia of the hip

    PubMed Central

    Qiu, Aizhen; Yang, Zhongxiu; Wang, Jiping; Wang, Taotao

    2016-01-01

    The aim of the study was to assess the clinical value of ultrasound screenings for the developmental dysplasia of the hip (DDH) and explore its etiology in high-risk infants with cerebral palsy in follow-up visits. A group of 98 cases of infants at high-risk of cerebral palsy who received rehabilitation treatment between July, 2009 and July, 2010 were selected. Infants included 58 men and 40 women, aged <6 months and not lost to follow-up visits. Ultrasound (using Graf static inspection) screening of hips was performed and the infants with abnormalities were given clinical intervention, and 1- to 2-year-old infants were given outpatient follow-ups. The results were analyzed and there were 40 abnormal cases among the 98 cases of infants at high risk of cerebral palsy, including 18 cases of unstable hip joint, and 22 cases of DDH (12 cases of hip dysplasia, 3 cases of hip subluxation and 7 cases of hip dislocation). Early clinical intervention for infants with hip dysplasia and outpatient follow up for infants aged 1–2 years was carried out and had ischemic necrosis of femoral head, with the exception of 1 case of femoral detorsion that was poorly restored. In conclusion, the probability of DDH was higher in infants at high-risk of cerebral palsy compared to the normal infants. Hip ultrasound is a safe, simple, and effective screening method for these infants, which is of great clinical significance for an earlier diagnosis and treatment of DDH in infants with cerebral palsy. PMID:27698744

  4. A vast range of opportunities for feeding the world in 2050: trade-off between diet, N contamination and international trade

    NASA Astrophysics Data System (ADS)

    Billen, Gilles; Lassaletta, Luis; Garnier, Josette

    2015-02-01

    Through a detailed analysis of the FAO database, we have constructed a generalized representation of the nitrogen transfers characterizing the current agro-food system (GRAFS) of 12 macro-regions of the world in terms of functional relationships between crop farming, livestock breeding and human nutrition. Based on this model, and maintaining the current cropland areas and the performance of cropping and livestock systems in each region, we have assessed the possibilities of meeting the protein requirements of the estimated world population in 2050, according to various combinations of three critical drivers namely human diet (total amount of protein consumed and share of animal protein in this total), regional livestock production and crop fertilization intensity, in each region. The results show that feeding the projected 2050 world population would generally imply higher levels of inter-regional trade and of environmental nitrogen contamination than the current levels, but that the scenarios with less recourse to inter-regional trade generally produce less N losses to the environment. If an equitable human diet (in terms of protein consumption) is to be established globally (the same in all regions of the world), the fraction of animal protein should not exceed 40% of a total ingestion of 4 kgN capita-1 yr-1, or 25% of a total consumption of 5 kgN capita-1 yr-1. Our results show that slightly improving the agronomical performance in the most deficient regions (namely Maghreb, the Middle East, sub-Saharan Africa, and India) would make it possible not only to meet the global protein requirements with much less international trade (hence more food sovereignty), but also to reduce N environmental contamination the most efficiently.

  5. Development of an Advanced Simulator to Model Mobility Control and Geomechanics during CO{sub 2} Floods

    SciTech Connect

    Delshad, Mojdeh; Wheeler, Mary; Sepehrnoori, Kamy; Pope, Gary

    2013-12-31

    The simulator is an isothermal, three-dimensional, four-phase, compositional, equation-of– state (EOS) simulator. We have named the simulator UTDOE-CO2 capable of simulating various recovery processes (i.e., primary, secondary waterflooding, and miscible and immiscible gas flooding). We include both the Peng-Robinson EOS and the Redlich-Kwong EOS models. A Gibbs stability test is also included in the model to perform a phase identification test to consistently label each phase for subsequent property calculations such as relative permeability, viscosity, density, interfacial tension, and capillary pressure. Our time step strategy is based on an IMPEC-type method (implicit pressure and explicit concentration). The gridblock pressure is solved first using the explicit dating of saturation-dependent terms. Subsequently, the material balance equations are solved explicitly for the total concentration of each component. The physical dispersion term is also included in the governing equations. The simulator includes (1) several foam model(s) for gas mobility control, (2) compositional relative permeability models with the hysteresis option, (3) corner point grid and several efficient solvers, (4) geomechanics module to compute stress field as the result of CO{sub 2} injection/production, (5) the format of commercial visualization software, S3graf from Science-soft Ltd., was implemented for user friendly visualization of the simulation results. All tasks are completed and the simulator was fully tested and delivered to the DOE office including a user’s guide and several input files and the executable for Windows Pcs. We have published several SPE papers, presented several posters, and one MS thesis is completed (V. Pudugramam, 2013) resulting from this DOE funded project.

  6. Grain-size evolution in suspended sediment and deposits from the 2004 and 2008 controlled-flood experiments in Marble and Grand Canyons, Arizona

    USGS Publications Warehouse

    Draut, Amy E.; Topping, David J.; Rubin, David M.; Wright, Scott A.; Schmidt, John C.

    2010-01-01

    Since the closure of Glen Canyon Dam in 1963, the hydrology, sediment supply, and distribution and size of modern alluvial deposits in the Colorado River through Grand Canyon have changed substantially (e.g., Howard and Dolan, 1981; Johnson and Carothers, 1987; Webb et al., 1999; Rubin et al., 2002; Topping et al., 2000, 2003; Wright et al., 2005; Hazel et al., 2006). The dam has reduced the fluvial sediment supply at the upstream boundary of Grand Canyon National Park by about 95 percent. Regulation of river discharge by dam operations has important implications for the storage and redistribution of sediment in the Colorado River corridor. In the absence of natural floods, sediment is not deposited at elevations that regularly received sediment before dam closure. There has been a systemwide decrease in the size and number of subaerially exposed fluvial sand deposits since the 1960s, punctuated by episodic aggradation during the exceptional high-flow intervals in the early 1980s and by sediment input from occasional tributary floods (Beus and others, 1985; Schmidt and Graf, 1990; Kearsley et al., 1994; Schmidt et al., 2004; Wright et al., 2005; Hazel et al., 2006). Fluvial sandbars are an important component of riparian ecology that, among other functions, enclose eddy backwaters that form native-fish habitat, provide a source for eolian sand that protects some archaeological sites, and are used as campsites by thousands of river-runners annually (Rubin et al., 1990; Kearsley et al., 1994; Neal et al., 2000; Wright et al., 2005; Draut and Rubin, 2008).

  7. CD151-α3β1 integrin complexes are prognostic markers of glioblastoma and cooperate with EGFR to drive tumor cell motility and invasion

    PubMed Central

    Xu, Bingwei; Deng, Xinyu; Alfáro, Jose E.; Chen, Li; Napier, Dana; Lu, Michael; Huang, Jian-An; Liu, Chunming; Thibault, Olivier; Segal, Rosalind; Zhou, Binhua P.; Kyprianou, Natasha; Horbinski, Craig; Yang, Xiuwei H.

    2015-01-01

    Glioblastoma, one of the most aggressive forms of brain cancer, is featured by high tumor cell motility and invasiveness, which not only fuel tumor infiltration, but also enable escape from surgical or other clinical interventions. Thus, better understanding of how these malignant traits are controlled will be key to the discovery of novel biomarkers and therapies against this deadly disease. Tetraspanin CD151 and its associated α3β1 integrin have been implicated in facilitating tumor progression across multiple cancer types. How these adhesion molecules are involved in the progression of glioblastoma, however, remains largely unclear. Here, we examined an in-house tissue microarray-based cohort of 96 patient biopsies and TCGA dataset to evaluate the clinical significance of CD151 and α3β1 integrin. Functional and signaling analyses were also conducted to understand how these molecules promote the aggressiveness of glioblastoma at molecular and cellular levels. Results from our analyses showed that CD151 and α3 integrin were significantly elevated in glioblastomas at both protein and mRNA levels, and exhibited strong inverse correlation with patient survival (p < 0.006). These adhesion molecules also formed tight protein complexes and synergized with EGF/EGFR to accelerate tumor cell motility and invasion. Furthermore, disruption of such complexes enhanced the survival of tumor-bearing mice in a xenograft model, and impaired activation of FAK and small GTPases. Also, knockdown- or pharmacological agent-based attenuation of EGFR, FAK or Graf (ARHGAP26)/small GTPase-mediated pathways markedly mitigated the aggressiveness of glioblastoma cells. Collectively, our findings provide clinical, molecular and cellular evidence of CD151-α3β1 integrin complexes as promising prognostic biomarkers and therapeutic targets for glioblastoma. PMID:26377974

  8. Neonatal clinical screening of the hip in the diagnosis of developmental dysplasia of the hip: a 15-year prospective longitudinal observational study.

    PubMed

    Mace, J; Paton, R W

    2015-02-01

    Over a 15-year prospective period, 201 infants with a clinically unstable hip at neonatal screening were subsequently reviewed in a 'one stop' clinic where they were assessed clinically and sonographically. Their mean age was 1.62 weeks (95% confidence interval (CI) 1.35 to 1.89). Clinical neonatal hip screening revealed a sensitivity of 62% (mean, 62.6 95%CI 50.9 to 74.3), specificity of 99.8% (mean, 99.8, 95% CI 99.7 to 99.8) and positive predictive value (PPV) of 24% (mean, 26.2, 95% CI 19.3 to 33.0). Static and dynamic sonography for Graf type IV dysplastic hips had a 15-year sensitivity of 77% (mean, 75.8 95% CI 66.9 to 84.6), specificity of 99.8% (mean, 99.8, 95% CI 99.8 to 99.8) and a PPV of 49% (mean, 55.1, 95% CI 41.6 to 68.5). There were 36 infants with an irreducible dislocation of the hip (0.57 per 1000 live births), including six that failed to resolve with neonatal splintage. Most clinically unstable hips referred to a specialist clinic are female and stabilise spontaneously. Most irreducible dislocations are not identified from this neonatal instability group. There may be a small subgroup of females with instability of the hip which may be at risk of progression to irreducibility despite early treatment in a Pavlik harness. A controlled study is required to assess the value of neonatal clinical screening programmes. PMID:25628293

  9. An Illumination Modeling System for Human Factors Analyses

    NASA Technical Reports Server (NTRS)

    Huynh, Thong; Maida, James C.; Bond, Robert L. (Technical Monitor)

    2002-01-01

    Seeing is critical to human performance. Lighting is critical for seeing. Therefore, lighting is critical to human performance. This is common sense, and here on earth, it is easily taken for granted. However, on orbit, because the sun will rise or set every 45 minutes on average, humans working in space must cope with extremely dynamic lighting conditions. Contrast conditions of harsh shadowing and glare is also severe. The prediction of lighting conditions for critical operations is essential. Crew training can factor lighting into the lesson plans when necessary. Mission planners can determine whether low-light video cameras are required or whether additional luminaires need to be flown. The optimization of the quantity and quality of light is needed because of the effects on crew safety, on electrical power and on equipment maintainability. To address all of these issues, an illumination modeling system has been developed by the Graphics Research and Analyses Facility (GRAF) and Lighting Environment Test Facility (LETF) in the Space Human Factors Laboratory at NASA Johnson Space Center. The system uses physically based ray tracing software (Radiance) developed at Lawrence Berkeley Laboratories, a human factors oriented geometric modeling system (PLAID) and an extensive database of humans and environments. Material reflectivity properties of major surfaces and critical surfaces are measured using a gonio-reflectometer. Luminaires (lights) are measured for beam spread distribution, color and intensity. Video camera performances are measured for color and light sensitivity. 3D geometric models of humans and the environment are combined with the material and light models to form a system capable of predicting lighting conditions and visibility conditions in space.

  10. Clinical evaluation of ultrasound screening in follow-up visits of infants with cerebral palsy at high risk for developmental dysplasia of the hip

    PubMed Central

    Qiu, Aizhen; Yang, Zhongxiu; Wang, Jiping; Wang, Taotao

    2016-01-01

    The aim of the study was to assess the clinical value of ultrasound screenings for the developmental dysplasia of the hip (DDH) and explore its etiology in high-risk infants with cerebral palsy in follow-up visits. A group of 98 cases of infants at high-risk of cerebral palsy who received rehabilitation treatment between July, 2009 and July, 2010 were selected. Infants included 58 men and 40 women, aged <6 months and not lost to follow-up visits. Ultrasound (using Graf static inspection) screening of hips was performed and the infants with abnormalities were given clinical intervention, and 1- to 2-year-old infants were given outpatient follow-ups. The results were analyzed and there were 40 abnormal cases among the 98 cases of infants at high risk of cerebral palsy, including 18 cases of unstable hip joint, and 22 cases of DDH (12 cases of hip dysplasia, 3 cases of hip subluxation and 7 cases of hip dislocation). Early clinical intervention for infants with hip dysplasia and outpatient follow up for infants aged 1–2 years was carried out and had ischemic necrosis of femoral head, with the exception of 1 case of femoral detorsion that was poorly restored. In conclusion, the probability of DDH was higher in infants at high-risk of cerebral palsy compared to the normal infants. Hip ultrasound is a safe, simple, and effective screening method for these infants, which is of great clinical significance for an earlier diagnosis and treatment of DDH in infants with cerebral palsy.

  11. Wheat Transpiration Response to Soil Heterogeneity

    NASA Astrophysics Data System (ADS)

    Langensiepen, M.; Kupisch, M.; Cai, G.; Vanderborght, J.; Stadler, A.; Hüging, H.; Ewert, F.

    2014-12-01

    Measuring sap-flow in thin wheat tillers has been difficult so far due to technical difficulties associated with the application of the heat-balance method for this purpose. We developed a new method which solved this problem (Langensiepen et al. 2014) and applied it during four consecutive vegetation seasons for determining tiller transpiration rates in a wheat field with strong soil heterogeneity. The transpiration rates differed insignificantly between different field sections characterized by strong differences in physical soil conditions, regardless whether the crop was irrigated or supplied with variable rainwater. Tiller transpiration in a sheltered section was slightly reduced. Maximum leaf vapor conductance didn't differ among these different conditions, except under severe water stress conditions. Leaf water potential varied considerably during daily cycles under all circumstances. These responses are typical for plants with anisohydric behaviors which are characterized by small sensitivities of guard cells to critical leaf water potential thresholds and high photosynthetic productivity under absent or mild water stress. Recent studies conducted in Eucalyptus, tomato, and Arabidopsis plants have shown that the transition from mild to severe stress in anisohydric plants is marked by an increasing sensitivity of stomatal control to the transpiration rate. The results of this study demonstrate that this also seems to be the case for wheat. This practically implies that the parameterization of models calculating wheat canopy flux responses to soil heterogeneity patterns must not only account for the crop-type specific soil-vegetation pattern interaction under absent or mild stress, but also for additional mechanisms which kick in when water stress becomes severe. Langensiepen, M., Kupisch, M., Graf, A., Schmidt, M., Ewert, F. (2014) Improving the stem heat balance method for determining sap-flow in wheat. Agric. For. Met. 186: 34-42

  12. Swiss AlpArray: deployment of the Swiss AlpArray temporary broad-band stations and their noise characterization

    NASA Astrophysics Data System (ADS)

    Molinari, Irene; Kissling, Edi; Clinton, John; Hetényi, György; Šipka, Vesna; Stipćević, Josip; Dasović, Iva; Solarino, Stefano; Wéber, Zoltán; Gráczer, Zoltán; Electronics Lab, SED

    2016-04-01

    One of the main actions of the AlpArray European initiative is the deployment of a dense seismic broad-band network, that complements the existing permanent stations. This will ensure a spatially homogeneous seismic coverage of the greater Alpine area for at least two years, allowing a great number of innovative scientific works to be carried out. Our contribution to the AlpArray Seismic Network consists in the deployment of 24 temporary broad-band stations: three in Switzerland, twelve in Italy, three in Croatia, three in Bosnia and Herzegovina and three in Hungary. This deployment is lead by ETH Zurich and founded by the Swiss-AlpArray Sinergia programme by SNSF, and is the result of a fruitful collaboration between five research institutes. Stations were installed between Autumn and Winter 2015. Our installations are both free field and in-house and consist of 21 STS-2 and 3 Trillium Compact sensors equipped with Taurus digitizers and 3G telemetry sending data in real time to the ETH EIDA node. In this work, we present sites and stations setting and we discuss in details the characteristics in terms of site effects and noise level of each station. In particular we analyse the power spectral density estimates investigating the major source of noise and the background noise related to seasons, time of the day, human activities and type of installation. In addition we will show examples of data usage - i.e. earthquake locations, noise cross correlations, measures of surface wave dispersion curves. We thanks the Swiss AlpArray Field Team: Blanchard A., Erlanger E. D., Jarić D., Herak D., M. Herak, Hermann M., Koelemeijer P. J., Markušić S., Obermann A., Sager K., Šikman S., Singer J., Winterberg S. SED Electronic Lab: Barman S., Graf P., Hansemann R., Haslinger F., Hiemer S., Racine R., Tanner R., Weber F.

  13. Statistical Comparison of the Baseline Mechanical Properties of NBG-18 and PCEA Graphite

    SciTech Connect

    Mark C. Carroll; David T. Rohrbaugh

    2013-08-01

    High-purity graphite is the core structural material of choice in the Very High Temperature Reactor (VHTR), a graphite-moderated, helium-cooled design that is capable of producing process heat for power generation and for industrial process that require temperatures higher than the outlet temperatures of present nuclear reactors. The Baseline Graphite Characterization Program is endeavoring to minimize the conservative estimates of as-manufactured mechanical and physical properties by providing comprehensive data that captures the level of variation in measured values. In addition to providing a comprehensive comparison between these values in different nuclear grades, the program is also carefully tracking individual specimen source, position, and orientation information in order to provide comparisons and variations between different lots, different billets, and different positions from within a single billet. This report is a preliminary comparison between the two grades of graphite that were initially favored in the two main VHTR designs. NBG-18, a medium-grain pitch coke graphite from SGL formed via vibration molding, was the favored structural material in the pebble-bed configuration, while PCEA, a smaller grain, petroleum coke, extruded graphite from GrafTech was favored for the prismatic configuration. An analysis of the comparison between these two grades will include not only the differences in fundamental and statistically-significant individual strength levels, but also the differences in variability in properties within each of the grades that will ultimately provide the basis for the prediction of in-service performance. The comparative performance of the different types of nuclear grade graphites will continue to evolve as thousands more specimens are fully characterized from the numerous grades of graphite being evaluated.

  14. Merging deterministic and probabilistic approaches to forecast volcanic scenarios

    NASA Astrophysics Data System (ADS)

    Peruzzo, E.; Bisconti, L.; Barsanti, M.; Flandoli, F.; Papale, P.

    2009-04-01

    Volcanoes are extremely complex systems largely inaccessible to direct observation. As a consequence, many quantities which are relevant in determining the physical and chemical processes occurring at volcanoes are largely uncertain. On the other hand, the demand for eruption scenario forecast at many hazardous volcanoes in the world is pressing, reflecting into the development and use of increasingly complex physical models and numerical codes. Such codes are capable of accounting for the extremely complex, non-linear behaviour of the volcanic processes, and for the roles of several quantities in determining volcanic scenarios and hazards. However, they often require enormous computer resources and imply long (order of days to weeks) CPU times even on the most advanced parallel computation systems available to-date. As a consequence, they can hardly be used to reasonably cover the spectrum of possible conditions expected at a given volcano. At this purpose, we have started the development of a mixed deterministic-probabilistic approach with the aim of substantially reducing (form order 10000 to 10) the number of simulations needed to adequately represent possible scenarios and their probability of occurrence, corresponding to a given set of probability distributions for the initial/boundary conditions characterizing the system. The core of the problem is to find a "best" discretization of the continuous density function describing the random variables input to the model. This is done through the stochastic quantization theory (Graf and Luschgy, 2000). The application of this theory to volcanic scenario forecast has been tested through both an oversimplified analytical model and a more complex numerical model for magma flow in volcanic conduits, the latter still running in relatively short times to allow comparison with Monte Carlo simulations. The final aim is to define proper strategies and paradigms for application to more complex, time-demanding codes

  15. Revisiting the question of the magnitude and intensity of the ~73 ka Toba eruption

    NASA Astrophysics Data System (ADS)

    Herzog, M.; Gatti, E.; Oppenheimer, C.

    2011-12-01

    The Younger Toba Tuff eruption, approximately 73 ka ago, is the largest known for the Quaternary and its climate, environmental and human consequences are keenly debated (Oppenheimer, 2011). However, to date, the estimates of its magnitude, intensity and duration are based on crude calculations. More robust estimation of these parameters with uncertainty bounds would represent a significant step in improving our understanding of the event. We report here on preliminary steps towards refined estimates of the YTT eruption parameters based on the recent development of a computational model that accounts for the complex dynamics of co-ignimbrite ash clouds (Herzog et al., 2010), and constraints from grain size data for distal deposits of YTT ash fallout. Recent studies (Herzog and Graf, 2010) showed that the height of co-ignimbrite plumes is largely insensitive to the areal forcing above a certain size limit due to the formation of multiple updrafts. Depending on the eruption intensity internal plume dynamics can dominate the horizontal transport in the umbrella region over large areas. Therefore the column height could act as self-limiting factor in the distribution of co-ignimbrite ash, evidencing the major role played by other factors, such as internal plume dynamics. Transport by atmospheric mean winds will only become important at a certain distance away from the source. Here, we parameterize the Active Tracer High Resolution Atmospheric Model (ATHAM, Herzog et al., 2003) for YTT co-ignimbrite cloud simulations, so as to reproduce particle size distributions known for terrestrial and marine YTT deposits. The particle size distributions, characterized through laser diffraction, have been collected from 350 km, 3,000 and 3,700 km from the vent. We report on the model setup, new constrains for the Toba ash distribution and on initial sensitivity studies that identify key sources of error propagation.

  16. The effects of ion mass variation and domain size on octupolar out-of-plane magnetic field generation in collisionless magnetic reconnection

    NASA Astrophysics Data System (ADS)

    Graf von der Pahlen, J.; Tsiklauri, D.

    2015-03-01

    Graf von der Pahlen and Tsiklauri [Phys. Plasmas 21, 060705 (2014)] established that the generation of octupolar out-of-plane magnetic field structure in a stressed X-point collapse is due to ion currents. The field has a central region, comprising of the well-known quadrupolar field (quadrupolar components), as well as four additional poles of reversed polarity closer to the corners of the domain (octupolar components). In this extended work, the dependence of the octupolar structure on domain size and ion mass variation is investigated. Simulations show that the strength and spatial structure of the generated octupolar magnetic field is independent of ion to electron mass ratio; thus showing that ion currents play a significant role in out-of-plane magnetic structure generation in physically realistic scenarios. Simulations of different system sizes show that the width of the octupolar structure remains the same and has a spacial extent of the order of the ion inertial length. The width of the structure thus appears to be independent on boundary condition effects. The length of the octupolar structure, however, increases for greater domain sizes, prescribed by the external system size. This was found to be a consequence of the structure of the in-plane magnetic field in the outflow region halting the particle flow and thus terminating the in-plane currents that generate the out-of-plane field. The generation of octupolar magnetic field structure is also established in a tearing-mode reconnection scenario. The differences in the generation of the octupolar field and resulting qualitative differences between X-point collapse and tearing-mode are discussed.

  17. Numerical Generation of Dense Plume Fingers in Unsaturated Homogeneous Porous Media

    NASA Astrophysics Data System (ADS)

    Cremer, C.; Graf, T.

    2012-04-01

    In nature, the migration of dense plumes typically results in the formation of vertical plume fingers. Flow direction in fingers is downwards, which is counterbalanced by upwards flow of less dense fluid between fingers. In heterogeneous media, heterogeneity itself is known to trigger the formation of fingers. In homogeneous media, however, fingers are also created even if all grains had the same diameter. The reason is that pore-scale heterogeneity leading to different flow velocities also exists in homogeneous media due to two effects: (i) Grains of identical size may randomly arrange differently, e.g. forming tetrahedrons, hexahedrons or octahedrons. Each arrangement creates pores of varying diameter, thus resulting in different average flow velocities. (ii) Random variations of solute concentration lead to varying buoyancy effects, thus also resulting in different velocities. As a continuation of previously made efforts to incorporate pore-scale heterogeneity into fully saturated soil such that dense fingers are realistically generated (Cremer and Graf, EGU Assembly, 2011), the current paper extends the research scope from saturated to unsaturated soil. Perturbation methods are evaluated by numerically re-simulating a laboratory-scale experiment of plume transport in homogeneous unsaturated sand (Simmons et al., Transp. Porous Media, 2002). The following 5 methods are being discussed: (i) homogeneous sand, (ii) initial perturbation of solute concentration, (iii) spatially random, time-constant perturbation of solute source, (iv) spatially and temporally random noise of simulated solute concentration, and (v) random K-field that introduces physically insignificant but numerically significant heterogeneity. Results demonstrate that, as opposed to saturated flow, perturbing the solute source will not result in plume fingering. This is because the location of the perturbed source (domain top) and the location of finger generation (groundwater surface) do not

  18. Sustained stimulation of soil respiration and CO2 release from an agricultural soil after 10 years of experimental warming

    NASA Astrophysics Data System (ADS)

    Munch, Jean Charles; Graf, Wolfgang; Reichenstein, Markus; Reth, Sascha

    2010-05-01

    A number of forest and grassland studies indicated that stimulation of the soil respiration by soil warming ceases after a couple of years (Luo et al 2001). A long-term soil warming lysimeter experiment (soil monolythes from an agricultural field, 1m2 x 2 Meter depth, temperature = ambient + 3°C; with a regionally usual crop rotation with 5 crops) was conducted in southern Germany. It results in a sustained stimulation of soil respiration after 10 years. Moreover, both warmed and control treatments exhibited a similar temperature response of soil respiration indicating that adaptation in terms of temperature sensitivity was absent. Carbon dioxide concentration measurements within the profiles are supporting these findings. The increased soil respiration occurred although vegetation productivity in the warmed treatment was not higher than in the control plots. These findings strongly contrast current soil carbon modeling concepts, where carbon pools decay according to first-order kinetics, and thus a depletion of labile soil carbon pools leads to an apparent down-regulation of microbial respiration (Knorr et al 2005). Consequently, the potential for positive carbon-climate cycle feedback may be larger than represented in current models of soil carbon turnover and in general assessments. Literatur Knorr W, Prentice I C, House J I and Holland A 2005 Long-term sensitivity of soil carbon turnover to warming Nature 433 298-301 Luo Y, Wan S, Hui D and Wallace L L 2001 Acclimatization of soil respiration to warming in a tall grass prairie Nature 413 622 - 5 Reth S. Graf W, Reichenstein M, Munch J.C. 2009 Sustained stimulation of soil respiration after 10 years of experimental warming Environmental Research Letters 4(2) 024005

  19. The effects of ion mass variation and domain size on octupolar out-of-plane magnetic field generation in collisionless magnetic reconnection

    SciTech Connect

    Graf von der Pahlen, J.; Tsiklauri, D.

    2015-03-15

    Graf von der Pahlen and Tsiklauri [Phys. Plasmas 21, 060705 (2014)] established that the generation of octupolar out-of-plane magnetic field structure in a stressed X-point collapse is due to ion currents. The field has a central region, comprising of the well-known quadrupolar field (quadrupolar components), as well as four additional poles of reversed polarity closer to the corners of the domain (octupolar components). In this extended work, the dependence of the octupolar structure on domain size and ion mass variation is investigated. Simulations show that the strength and spatial structure of the generated octupolar magnetic field is independent of ion to electron mass ratio; thus showing that ion currents play a significant role in out-of-plane magnetic structure generation in physically realistic scenarios. Simulations of different system sizes show that the width of the octupolar structure remains the same and has a spacial extent of the order of the ion inertial length. The width of the structure thus appears to be independent on boundary condition effects. The length of the octupolar structure, however, increases for greater domain sizes, prescribed by the external system size. This was found to be a consequence of the structure of the in-plane magnetic field in the outflow region halting the particle flow and thus terminating the in-plane currents that generate the out-of-plane field. The generation of octupolar magnetic field structure is also established in a tearing-mode reconnection scenario. The differences in the generation of the octupolar field and resulting qualitative differences between X-point collapse and tearing-mode are discussed.

  20. Effects of soil water availability on water fluxes in winter wheat

    NASA Astrophysics Data System (ADS)

    Cai, G.; Vanderborght, J.; Langensiepen, M.; Vereecken, H.

    2014-12-01

    could focus on a long time (e.g. from vegetation to maturity) effect under different soil water conditions, such as irrigated, sheltered and normal status. Langensiepen, M., Kupisch, M., Graf, A., Schmidt, M. and Ewert, F., 2014. Improving the stem heat balance method for determining sap-flow in wheat. Agricultural and Forest Meteorology, 186: 34-42.

  1. Identifying and Managing Data Validity Challenges with Automated Data Checks in the AmeriFlux Flux Measurement Network

    NASA Astrophysics Data System (ADS)

    Poindexter, C.; Pastorello, G.; Papale, D.; Trotta, C.; Ribeca, A.; Canfora, E.; Faybishenko, B.; Samak, T.; Gunter, D.; Hollowgrass, R.; Agarwal, D.

    2014-12-01

    AmeriFlux is a network of sites managed by independent investigators measuring carbon, water and heat fluxes. Individual investigators perform many data validity checks. Network-level data validity checks are also being applied to increase network-wide data consistency. A number of different types or errors occur in flux data, and while corrections have been developed to address some types of errors, other error types can be difficult to detect. To identify errors rapidly and consistently, we have developed automated data validity checks that rely on theoretical limits or relationships for specific measured variables. We present an example of a data validity check that is being developed for the friction velocity u*. The friction velocity is a crucial variable used to identify when low turbulent mixing in the atmospheric boundary layer invalidates eddy covariance measurements of fluxes. It is measured via sonic anemometer and is related to the wind speed WS, the measurement height relative to the canopy height, and the surface roughness, through the log law. Comparing independent measurements of WS and u* can help identify issues related to the sensor but doesn't take into consideration changes in the canopy (e.g. due to leaf emergence). The u* data check proposed relies on recent work comparing multiple methods for determining the aerodynamic roughness length z0 and zero plane displacement d (Graf, A., A. van de Boer, A. Moene & H. Vereecken, 2014, Boundary-Layer Meteorol., 151, 373-387). These methods, each of which is most robust across a different atmospheric stability range, yield multiple estimates for z0 and d at daily resolution. We use these multiple estimates for z0 and d, as well as half-hourly wind speeds and Obukhov length scales and their uncertainties to generate a predicted u* and a tolerance around this predicted value. In testing, this check correctly identified as invalid u* data known to be erroneous but did not flag data that could look

  2. Evolution of a Directional Wave Spectrum in a 3D Marginal Ice Zone with Random Floe Size Distribution

    NASA Astrophysics Data System (ADS)

    Montiel, F.; Squire, V. A.

    2013-12-01

    A new ocean wave/sea-ice interaction model is proposed that simulates how a directional wave spectrum evolves as it travels through a realistic marginal ice zone (MIZ), where wave/ice dynamics are entirely governed by coherent conservative wave scattering effects. Field experiments conducted by Wadhams et al. (1986) in the Greenland Sea generated important data on wave attenuation in the MIZ and, particularly, on whether the wave spectrum spreads directionally or collimates with distance from the ice edge. The data suggest that angular isotropy, arising from multiple scattering by ice floes, occurs close to the edge and thenceforth dominates wave propagation throughout the MIZ. Although several attempts have been made to replicate this finding theoretically, including by the use of numerical models, none have confronted this problem in a 3D MIZ with fully randomised floe distribution properties. We construct such a model by subdividing the discontinuous ice cover into adjacent infinite slabs of finite width parallel to the ice edge. Each slab contains an arbitrary (but finite) number of circular ice floes with randomly distributed properties. Ice floes are modeled as thin elastic plates with uniform thickness and finite draught. We consider a directional wave spectrum with harmonic time dependence incident on the MIZ from the open ocean, defined as a continuous superposition of plane waves traveling at different angles. The scattering problem within each slab is then solved using Graf's interaction theory for an arbitrary incident directional plane wave spectrum. Using an appropriate integral representation of the Hankel function of the first kind (see Cincotti et al., 1993), we map the outgoing circular wave field from each floe on the slab boundaries into a directional spectrum of plane waves, which characterizes the slab reflected and transmitted fields. Discretizing the angular spectrum, we can obtain a scattering matrix for each slab. Standard recursive

  3. Rheological properties of suspensions of interacting rodlike FD-virus particles

    NASA Astrophysics Data System (ADS)

    Graf, Christian; Kramer, Hansgerd; Deggelmann, Martin; Hagenbüchle, Martin; Johner, Christian; Martin, Christoph; Weber, Reinhart

    1993-03-01

    Low shear (γ˙=1 s-1) and shear rate dependent (1 s-1<γ˙<100 s-1) viscosity measurements on aqueous suspensions of rodlike FD-virus particles (length=880 nm, diameter=9 nm) below and above the overlap concentration c* =1 particle/length3 are presented. Properties like intrinsic viscosity [η], the virus concentration and shear rate dependence of η are studied in deionized (``saltfree'') suspensions and in the presence of NaCl, where the Coulomb interaction between the particles is totally screened. In the latter case, [η] is in excellent agreement with theoretical predictions [A. R. Altenberger and J. S. Dahler, Macromolecules 18, 1700 (1985); R. M. Davis and W. B. Russel, Macromolecules 20, 518 (1987)]. As a function of the virus concentration, η follows certain power laws in c. The observed exponents depend here on the applied shear rate. In the low shear region, η(c) can be described by the well known Huggins behavior. An attempt to fit the data by the popular stretched exponential form failed. The variation of η with shear rate is compared with available theories [M. Doi and S. F. Edwards, The Theory of Polymer Dynamics (Clarendon, Oxford, 1986); A. R. Altenberger and J. S. Dahler, Macromolecules 18, 1700 (1985); J. S. Dahler, S. Fesciyan, and N. Xystris, Macromolecules 16, 1673 (1983)]. A theory of Hess [Z. Naturforsch. Teil A 35, 915 (1980)] allows us to evaluate the concentration dependent values of the rotational diffusion constant Drot from the η(γ˙) data which are found to be in very good agreement with the values of Drot, obtained by electric or magnetic birefringence [H. Kramer, M. Deggelmann, C. Graf, M. Hagenbüchle, C. Johner, and R. Weber, Macromolecules 25, 4325 (1992); J. F. Maguire and J. P. McTague, Phys. Rev. Lett. 45, 1891 (1980); H. Nakamura and K. Okano, Phys. Rev. Lett. 50, 186 (1983)]. For strong Coulomb interaction among the suspended viruses no adequate theory is available. Therefore, the data achieved under these conditions

  4. Initial Comparison of Baseline Physical and Mechanical Properties for the VHTR Candidate Graphite Grades

    SciTech Connect

    Carroll, Mark C.

    2014-09-01

    High-purity graphite is the core structural material of choice in the Very High Temperature Reactor (VHTR) design, a graphite-moderated, helium-cooled configuration capable of producing thermal energy for power generation as well as process heat for industrial applications that require temperatures higher than the outlet temperatures of present nuclear reactors. The Baseline Graphite Characterization Program is establishing accurate as-manufactured mechanical and physical property distributions in nuclear-grade graphites by providing comprehensive data that captures the level of variation in measured values. In addition to providing a thorough comparison between these values in different graphite grades, the program is also carefully tracking individual specimen source, position, and orientation information in order to provide comparisons both in specific properties and in the associated variability between different lots, different billets, and different positions from within a single billet. This report is a preliminary comparison between each of the grades of graphite that are considered “candidate” grades from four major international graphite producers. These particular grades (NBG-18, NBG-17, PCEA, IG-110, and 2114) are the major focus of the evaluations presently underway on irradiated graphite properties through the series of Advanced Graphite Creep (AGC) experiments. NBG-18, a medium-grain pitch coke graphite from SGL from which billets are formed via vibration molding, was the favored structural material in the pebble-bed configuration. NBG-17 graphite from SGL is essentially NBG-18 with the grain size reduced by a factor of two. PCEA, petroleum coke graphite from GrafTech with a similar grain size to NBG-17, is formed via an extrusion process and was initially considered the favored grade for the prismatic layout. IG-110 and 2114, from Toyo Tanso and Mersen (formerly Carbone Lorraine), respectively, are fine-grain grades produced via an isomolding

  5. Small Specimen Data from a High Temperature HFIR Irradiation Experiment

    SciTech Connect

    Burchell, Timothy D; McDuffee, Joel Lee; Thoms, Kenneth R

    2014-01-01

    The HTV capsule is a High Flux Isotope Reactor (HFIR) target-rod capsule designed to operate at very high temperatures. The graphite containing section of the capsule (in core) is approximately 18 inches (457.2 mm) long and is separated into eight temperature zones. The specimen diameters within each zone are set to achieve the desired gas gap and hence design temperature (900 C, 1200 C or 1500 C). The capsule has five zones containing 0.400 inch (10.16 mm) diameter specimens, two zones containing 0.350 inch (8.89 mm) diameter specimens and one zone containing 0.300 inch (7.62 mm) diameter specimens. The zones have been distributed within the experiment to optimize the gamma heating from the HFIR core as well as minimize the axial heat flow in the capsule. Consequently, there are two 900 C zones, three 1200 C zones, and three 1500 C zones within the HTV capsule. Each zone contains nine specimens 0.210 0.002 inches (5.334 mm) in length. The capsule will be irradiated to a peak dose of 3.17 displacements per atom. The HTV specimens include samples of the following graphite grades: SGL Carbon s NBG-17 and NBG-18, GrafTech s PCEA, Toyo Tanso s IG-110, Mersen s 2114 and the reference grade H-451 (SGL Carbon). As part of the pre-irradiation program the specimens were characterized using ASTM Standards C559 for bulk density, and ASTM C769 for approximate Young s modulus from the sonic velocity. The probe frequency used for the determination of time of flight of the ultrasonic signal was 2.25 MHz. Marked volume (specimen diameter) effects were noted for both bulk density (increased with increasing specimen volume or diameter) and Dynamic Young s modulus (decreased with increasing specimen volume or diameter). These trends are extended by adding the property vs. diameter data for unirradiated AGC-1 creep specimens (nominally 12.5 mm-diameter x 25.4 mm-length). The relatively large reduction in Dynamic Young s Modulus was surprising given the trend for increasing density

  6. Biomechanical Evaluation of Pedicle Screw-Based Dynamic Stabilization Devices for the Lumbar Spine: A Systematic Review

    PubMed Central

    Ponnappan, Ravi K.; Song, Jason; Vaccaro, Alexander R.

    2008-01-01

    Study Design This study is a systematic review of published biomechanical studies involving pedicle screw-based posterior dynamic stabilization devices (PDS) with a special focus on kinematics and load transmission through the functional spine unit (FSU). Methods A literature search was performed via the PubMed online database from 1990 to 2008 using the following key words: “biomechanics,” “lumbar dynamic stabilization,” “Graf system,” “Dynesys,” and “posterior dynamic implant.” Citations were limited to papers describing biomechanics of pedicle screw-based PDS devices currently available for clinical use. Studies describing clinical experience, radiology, and in vivo testing were excluded from the review. Parameters measured included kinematics of the FSU (range of motion (ROM), neutral zone (NZ), and location of the center of rotation) and load transmission through the disk, facets, and instrumentation. Results A total of 27 publications were found that concerned the biomechanical evaluation of lumbar pedicle screw-based dynamic stabilization instrumentation. Nine in vitro experimental studies and 4 finite element analyses satisfied the inclusion criteria. The Dynesys implant was the most investigated pedicle screw-based PDS system. In vitro cadaveric studies mainly focused on kinematics comparing ROM of intact versus instrumented spines whereas finite element analyses allowed analysis of load transmission at the instrumented and adjacent levels. Conclusion Biomechanical studies demonstrate that pedicle screw-based PDS devices limit intervertebral motion while unloading the intervertebral disk. The implant design and the surgical technique have a significant impact on the biomechanical behavior of the instrumented spinal segment. The posterior placement of such devices results in non-physiologic intervertebral kinematics with a posterior shift of the axis of rotation. Biomechanical studies suggest that the difference at the adjacent level

  7. Depth-dependent Concentrations of Cosmogenic 10Be, 26Al, 36Cl, HEc, NEc, and ARc in the Old Woman Iron Meteorite

    NASA Astrophysics Data System (ADS)

    Lavielle, B.; Nishiizumi, K.; Marti, K.; Jeannot, J.-P.; Caffee, M. W.; Finkel, R. C.

    1995-09-01

    terrestrial age of Old Woman is probably less than 50,000 years. References: [1] Nishiizumi K. et al (1991) Meteoritics, 26, 379-380. [2] Schultz L. (1967) EPSL, 2, 87-89. [3] Graf T. et al., this volume.

  8. Barotropic and baroclinic energy conversions associated with planetary wave forcing of the northern stratospheric polar vortex

    NASA Astrophysics Data System (ADS)

    Liberato, M. L. R.; Castanheira, J. M.; Dacamara, C. C.

    2009-04-01

    An analysis of the energy conversion of barotropic and baroclinic planetary waves for extended winter in the extratropical Northern Hemisphere is presented. The analysis is based on a three-dimensional normal mode expansion of the global circulation of the atmosphere (Castanheira et al. 2002; Liberato et al. 2007). This method allows separating the atmospheric circulation into planetary (Rossby) and inertio-gravity waves as well as characterising each type of wave by the respective zonal, meridional and vertical structures. The 3-D normal mode scheme further allows evaluating the contribution of each type of wave for the global total (i.e., kinetic + available potential) atmospheric energy. A brief overview of the normal mode energetics of the global atmospheric circulation is given, focusing on the energy conversions between barotropic and baroclinic components of different vertical and horizontal scales. The methodology is applied to the global NCEP/NCAR (National Centers for Environmental Prediction / National Center for Atmospheric Research) reanalysis data set, using extended winter (November to March) daily means of the horizontal wind components (u, v) and of the geopotential height, at the 17 standard pressure levels, with the spatial horizontal resolution available (2.5° regular grid) and spanning the period 1957-2008. Obtained results are then used to relate the variability of the stratospheric polar vortex to the variability of the energy of the forcing planetary waves. Barotropic and baroclinic energy conversions associated with planetary wave forcing of the northern winter polar vortex are finally analysed, during rapid stratospheric vortex decelerations and accelerations. Castanheira, J. M., H.-F. Graf, C. DaCamara, and A. Rocha, 2002: Using a physical reference frame to study global circulation variability. J. Atmos. Sci., 59, 1490-1501. Liberato, M. L. R., J. M. Castanheira, L. da la Torre, C. C. DaCamara and L. Gimeno, 2007: Wave Energy Associated

  9. Depth Profiles of Cosmogenic Noble Gases in the Chondrite Knyahinya

    NASA Astrophysics Data System (ADS)

    Toe, S.; Lavielle, B.; Gilabert, E.; Simonoff, G. N.

    1993-07-01

    Concentrations and isotopic ratios of Ne, Ar, Kr, and Xe have been analyzed in 5-g size samples from different positions within the L5 chondrite Knyahinya. A previous work [1] has shown that Knyahinya experienced a single-stage exposure history (duration 40.5 Ma) as a meteoroid of approximately spherical shape (radius 45 cm). For these reasons, this meteorite represents a very interesting object to study depth profiles of cosmogenic nuclide concentrations and to test and improve model calculations of production rates. The procedure of extraction of noble gases adopted for this work, includes two pyrolyses respectively at about 450 degrees C and 650 degrees C, followed by a combustion step in pure O2 (15-25 torr pressure) at 650 degrees C before the complete melting of the sample [2]. This procedure allows a low-temperature extraction of a significant fraction of the Kr and Xe trapped noble gas component, leading to an enrichment of the cosmogenic component during the last temperature step. Concentration of trapped Ar, Kr, and Xe is 2-3 times lower than expected for a type 5 chondrite. The isotopic composition of the trapped Xe component analyzed in the combustion step is identical with the OC- Xe composition measured in Forest Vale [3]. Preliminary results show that concentration of cosmogenic 83Kr increases by 16% from the surface to the center when the ratio of cosmogenic 78Kr to 83Kr decreases from 0.157 to 0.136. The concentration of 81Kr has been measured in each sample. It increases from 0.0220 10^-12 cm^3 STP/g near the surface to 0.0255 10^-12 cm^3 STP/g at the center, in excellent agreement with the variations measured by Eugster [4] in other ordinary chondrites. Acknowledgments: This work was supported by C.N.R.S., by IN2P3 and by INSU (Programme National de Planetologie). References: [1] Graf Th. et al. (1990) GCA, 54, 2511-2520. [2] Gilabert E. and Lavielle B. (1991) Meteoritics, 26, 337. [3] Lavielle B. and Marti K. (1992) JGR, 97, 20875-20881. [4

  10. Analytic Simulation of the Elastic Waves Propagation in the Neighborhood of Fluid Filled Wells with Monopole Sources

    NASA Astrophysics Data System (ADS)

    Ávila-Carrera, R.; Sánchez-Sesma, F. J.; Spurlin, James H.; Valle-Molina, C.; Rodríguez-Castellanos, A.

    2014-09-01

    An analytic formulation to understand the scattering, diffraction and attenuation of elastic waves at the neighborhood of fluid filled wells is presented. An important, and not widely exploited, technique to carefully investigate the wave propagation in exploration wells is the logging of sonic waveforms. Fundamental decisions and production planning in petroleum reservoirs are made by interpretation of such recordings. Nowadays, geophysicists and engineers face problems related to the acquisition and interpretation under complex conditions associated with conducting open-hole measurements. A crucial problem that directly affects the response of sonic logs is the eccentricity of the measuring tool with respect to the center of the borehole. Even with the employment of centralizers, this simple variation, dramatically changes the physical conditions on the wave propagation around the well. Recent works in the numerical field reported advanced studies in modeling and simulation of acoustic wave propagation around wells, including complex heterogeneities and anisotropy. However, no analytical efforts have been made to formally understand the wireline sonic logging measurements acquired with borehole-eccentered tools. In this paper, the Graf's addition theorem was used to describe monopole sources in terms of solutions of the wave equation. The formulation was developed from the three-dimensional discrete wave-number method in the frequency domain. The cylindrical Bessel functions of the third kind and order zero were re-derived to obtain a simplified set of equations projected into a bi-dimensional plane-space for displacements and stresses. This new and condensed analytic formulation allows the straightforward calculation of all converted modes and their visualization in the time domain via Fourier synthesis. The main aim was to obtain spectral surfaces of transfer functions and synthetic seismograms that might be useful to understand the wave motion produced by the

  11. Aeolian sediment transport in vegetation canopies

    NASA Astrophysics Data System (ADS)

    Gromke, C.; Walter, B.; Burri, K.; Graf, F.; Lehning, M.

    2011-12-01

    potential to expand and improve the capability of wind erosion models for simulating sediment transport over vegetated surfaces. Reference: Burri, K., Gromke, C., Lehning, M., Graf, F. (2011) Aeolian sediment transport over vegetation canopies: A wind tunnel study with live plants. Journal of Aeolian Research, doi:10.1016/j.aeolia.2011.01.003.

  12. Cosmogenic Radionuclides in Antarctic Meteorites: Preliminary Results on Terrestrial Ages and Temporal Phenomena

    NASA Astrophysics Data System (ADS)

    Michlovich, E.; Vogt, S.; Wolf, S. F.; Elmore, D.; Lipschutz, M. E.

    1993-07-01

    the production rates for these radionuclides in this group of meteorites to be 18.2 +/- 2.3 and 58 +/- 13 dpm/kg respectively, consistent with production rates cited for falls [8]. Cosmic ray exposure ages using the ^10Be/^21Ne method outlined by Graf et al. [9] substantially agree with ages calculated from noble gases alone. Similar agreements are obtained between cosmic ray exposure ages based solely on noble gases and those calculated using ^26Al/^21Ne [9]. We calculated terrestrial ages using the secular equilibrium distribution for ^36Cl of 22.8 +/- 3.1 dpm/kg [10]. Our results are similar to those seen by Nishiizumi et al. [10], with a few ages ranging up to several hundred thousand years. It is worth noting that the Yamato meteorites measured in the present study, all of which happen to have been collected in the 1979 recovery effort ("Y79"), have a much older terrestrial age distribution (median age of 140 ka) than the Yamato distribution shown in [10]. We find it interesting that our Yamato age distribution is, however, consistent with the distribution of Y79 ages (median age, 110 ka) listed in [10], and that non-Y79 Yamato meteorites (median age in [10], 22 ka) seem to be responsible for a disproportionate number of the youngest Yamato meteorites. This possible collection area phenomenon is under investigation. Preliminary statistical analysis of the results using the preliminary terrestrial ages calculated here, trace-element data [3,4,11], and the methods elucidated in [2] is consistent with the notion that the meteorite flux sampled by the Earth has changed as a function of time. The latest results will be presented in Vail. References: [1] Koeberl C. and Cassidy W. A. (1991) GCA, 55, 3-18. [2] Lipschutz M. E. and Samuels S. M. (1991) GCA, 55, 19-34. [3] Wolf S. F. and Lipschutz M. E. (1992) LPS XXIII, 1545-1546. [4] Dodd R. T. et al. (1993) JGR, submitted. [5] Wetherill G. W. (1986) Nature, 319, 357-358. [6] Schultz L., personal communication. [7

  13. Contrail Cirrus Forecasts for the ML-CIRRUS Experiment and Some Comparison Results

    NASA Astrophysics Data System (ADS)

    Schumann, Ulrich; Graf, Kaspar; Bugliaro, Luca; Dörnbrack, Andreas; Giez, Andreas; Jurkat, Tina; Kaufmann, Stefan; Krämer, Martina; Minikin, Andreas; Schäfler, Andreas; Voigt, Christiane; Wirth, Martin; Zahn, Andreas; Ziereis, Helmut

    2015-04-01

    Model simulations with the contrail cirrus prediction model CoCiP driven by numerical weather prediction (NWP) data provided from the European Centre for Medium Range Forecasts (ECMWF) and global aircraft waypoint data show a mean computed cover (for optical depth larger than 0.1) of 0.23% globally, and 5.4% over mid Europe (Schumann and Graf, JGR, 2013). The computed mean longwave radiative forcing (RF) reaches 3 W m-2 over mid Europe (10°W-20°E and 40°N-55°N), and 0.13 W m-2 globally. The global net RF is about 40-60% smaller because of compensating shortwave cooling induced by contrails during daytime. The results depend on several model details such as the number of ice particles forming from aircraft soot emissions, the contrail plume dispersion, ice particle sedimentation etc., all influencing contrail life time and their optical properties. The quantitative results depend also strongly on ambient relative humidity, vertical motion and on ice water content of other cirrus predicted by the NWP model. In order to test and possibly improve this and other contrail models, high-quality observations are needed to which multi-parameter model output can be compared. The Mid-Latitude Cirrus Experiment ML-CIRRUS was performed (see C. Voigt et al., this conference) with a suite of in-situ and Lidar instruments for airborne measurements on the research aircraft HALO. Before and during the mission, CoCiP was run daily to provide 3-days forecasts of contrail cover using operational ECMWF forecasts and historical traffic data. CoCiP forecast output was made available in an internet tool twice a day for experiment planning. The one-day and two-day contrail forecasts often showed only small differences. Still, most recent forecasts and detailed satellite observations results were transmitted via satellite link to the crew for onboard campaign optimization. After the campaign, a data base of realistic air traffic data has been setup from various sources, and CoCiP was

  14. Climatic versus topographic forcing on the extend of major Alpine ice-caps

    NASA Astrophysics Data System (ADS)

    Salcher, Bernhard; Sternai, Pietro

    2015-04-01

    .e. after the mid-Pleistocene transition) show similar extensions. These new observations conflict with older stratigraphic models and no profound explanations have been found yet. Our aim is to explore these first-order feedback mechanisms impacting the growth and extend of Alpine ice shields through time and evolving topography by taking advantage of the comprehensive records and time constraints of glacial history available from the European Alps. Akçar, N., Ivy-Ochs, S., Alfimov, V., Claude, A., Graf, H.R., Dehnert, A., Kubik, P.W., Rahn, M., Kuhlemann, J., Schlüchter, C. (2014): The first major incision of the Swiss Deckenschotter landscape. Swiss J Geosci. DOI 10.1007/s00015-014-0176-6. Pedersen, V., Egholm, D.L. (2013): Glaciations in response to climate variations preconditioned by evolving topography. Nature, 493, 207-210. Preusser, F. (2004): Towards a chronology of the Late Pleistocene in the northern Alpine Foreland. Boreas 33, 195-210.

  15. Geogenic Gases and Red Wood Ant Clusters as Indicators for Neotectonic Activity at the Peninsula Bodanrück (South West Germany)

    NASA Astrophysics Data System (ADS)

    Berberich, G.; Klimetzek, D.; Schreiber, U.; Berberich, M.

    2012-04-01

    fault zones. Although small-scale distribution of RWA mounds did not correspond directly to geogenic gas concentrations (Berberich et al. 2012), their large-scale arrangement in three major rhomboidal clusters (1,276, 790 and 120 mounds) corresponding to three tectonic blocks directly maps the main stress field and the conjugated shear system in hierarchically succession. Two nest free corridors trending about 20° NNE-SSW separate these blocks and correlate well with the hypothesized NNE-SSW trending faults east of Stein am Rhein derived from focal plane analyses and might be linked to the northern edge of the "Permokarbontrog" (Graf 2009, Müller et al. 2002). These RWA-free corridors are interpreted as non-gaspermeable normal faults. The RWA nest distribution within the clusters show mostly NNW-SSE, WSW-ENE and NNE-SSW trending zones, which we associate as strike-slip faults, matching well those known from the Graben regime (Swisstopo 2008). The blocks are subjected to uplift, but they also undergo possible rotations relative to one another, which can be correlated with voids caused by dextral crustal block rotation. Considering all aspects, we interpret our findings as a possible double transpressional pop-up structure embedded between two dextral strike-slip faults prolonging the Mindelsee and Randen strike-slip faults.

  16. EDITORIAL: Focus on Advances in Surface and Interface Science 2008 FOCUS ON ADVANCES IN SURFACE AND INTERFACE SCIENCE 2008

    NASA Astrophysics Data System (ADS)

    Scheffler, Matthias; Schneider, Wolf-Dieter

    2008-12-01

    Iori, K Sakamoto, H Narita, A Kimura, M Taniguchi, S Qiao, K Hasegawa, K Shimada, H Namatame and S Blügel Activated associative desorption of C + O → CO from Ru(001) induced by femtosecond laser pulses S Wagner, H Öström, A Kaebe, M Krenz, M Wolf, A C Luntz and C Frischkorn Surface structure of Sn-doped In2O3 (111) thin films by STM Erie H Morales, Yunbin He, Mykola Vinnichenko, Bernard Delley and Ulrike Diebold Coulomb oscillations in three-layer graphene nanostructures J Güttinger, C Stampfer, F Molitor, D Graf, T Ihn and K Ensslin Adsorption processes of hydrogen molecules on SiC(001), Si(001) and C(001) surfaces Xiangyang Peng, Peter Krüger and Johannes Pollmann Fermi surface nesting in several transition metal dichalcogenides D S Inosov, V B Zabolotnyy, D V Evtushinsky, A A Kordyuk, B Büchner, R Follath, H Berger and S V Borisenko Probing molecule-surface interactions through ultra-fast adsorbate dynamics: propane/Pt(111) A P Jardine, H Hedgeland, D Ward, Y Xiaoqing, W Allison, J Ellis and G Alexandrowicz A novel method achieving ultra-high geometrical resolution in scanning tunnelling microscopy R Temirov, S Soubatch, O Neucheva, A C Lassise and F S Tautz

  17. The Role of Eolian Sediment in the Preservation of Archeologic Sites Along the Colorado River Corridor in Grand Canyon National Park, Arizona

    USGS Publications Warehouse

    Draut, Amy E.; Rubin, David M.

    2008-01-01

    Since the closure of Glen Canyon Dam in 1963, the natural hydrologic and sedimentary systems along the Colorado River in the Grand Canyon reach have changed substantially (see, for example, Andrews, 1986; Johnson and Carothers, 1987; Webb and others, 1999b; Rubin and others, 2002; Topping and others, 2003; Wright and others, 2005; Hazel and others, 2006b). The dam has reduced the fluvial sediment supply at the upstream boundary of Grand Canyon National Park by about 95 percent. Regulation of river discharge by dam operations has important implications for the storage and redistribution of sediment in the Colorado River corridor. In the absence of floods, sediment is not deposited at elevations that regularly received sediment before dam closure. Riparian vegetation has colonized areas at lower elevations than in predam time when annual floods removed young vegetation (Turner and Karpiscak, 1980). Together, these factors have caused a systemwide decrease in the size and number of subaerially exposed fluvial sand deposits since the 1960s, punctuated by episodic aggradation during the exceptional high-flow intervals in 1983-84, 1996, and 2004 and by sediment input from occasional tributary floods (Beus and others, 1985; Schmidt and Graf, 1987; Kearsley and others, 1994; Hazel and others, 1999; Schmidt and others, 2004; Wright and others, 2005). When the Bureau of Reclamation sponsored the creation of the Glen Canyon Environmental Studies (GCES) research initiative in 1982, research objectives included physical and biologic resources, whereas the effects of dam operations on cultural resources were not addressed (Fairley and others, 1994; Fairley, 2003). In the early 1980s, it was widely believed that because few archeologic sites were preserved within the river's annual-flood zone, cultural features would not be greatly affected by dam operations. Recent studies, however, indicate that alterations in the flow and sediment load of the Colorado River by Glen Canyon Dam

  18. Femoropopliteal bypass vs percutaneous transluminal angioplasty and stenting in treatment of peripheral artery diseases of infrainquinal segment - short-term results.

    PubMed

    Cvetanovski, M V; Jovev, S; Cvetanovska, M; Blazevski, B; Colanceski, R; Andreevska, T; Gramatnikovski, N; Kartalov, A

    2009-07-01

    (Full text is available at http://www.manu.edu.mk/prilozi). Critical limb ischaemia is a result of occlusive arterial disease in the infrainquinal segment and is a major indication for arterial revascularization, which implies a femoropopliteal bypass procedure or an interventional procedure - stent graf notting of the occluded segment. Although indications for both techniques are clearly defined, there are still controversies. Thus, the aim of this study was to determine short-term results in patients treated with these two treatment modalities. In the period between 2002 and 2008 a total of 70 patients with occlusive arte notrial diseases of the low extremity were analysed. In 50 out of 70 patients a femo notro notpopliteal bypass was made. Of these, in 30 (60%) patients PTFE material was used and in 20 (40%) patients an autologous saphenous vein graft was used. The other group comprised 20 patients who underwent stenting. In patients treated with surgical revas notcularization, the major indication for surgery was occlusive arterial disease in: stage II - in 10 patients (20%), stage III - in 5 patients (10%), stage IV - in 25 patients (50%) and the remaining 10 patients (20%) had subacute ischaemia. Arteriography showed three crural patent tributaries in 18% of the patients, two patent crural tributaries in 40% of the patients and one crural patent tributary in 32% of the patients. There were no significant differences concerning indications and arteriographic findings between the two subgroups. The follow-up period lasted for 6 months and the patency rate was 85% (17) for venous bypass, 11 (64.6%) - short-segment lesions (< 4 cm) and 6 (35.3%) lon notger segment lesions (> 4 cm) versus 76.5% (23) for PTFE graft (p < 0.05), of which 13 (56.5%) were short-segment (<4 cm) and 10 (43.5%) longer segment lesions (> 4 cm). The following results were obtained for the second group of patients: initially successful stents in 85%; failure in 15% or 2 patients; technical

  19. Simulations of Potential Runout and Deposition of the Ferguson Rockslide, Merced River Canyon, California

    USGS Publications Warehouse

    Denlinger, Roger P.

    2007-01-01

    of the rockslide moving five to ten times faster than the middle portion or headwall part of the slide. Downslope of the main rockslide mass, a talus slope consist in of angular blocks ranging in size from 0.1 to greater than 10 meters (Gallegos and DeGraff, 2006), buries Highway 140. Both the main rockslide and the talus consist of angular blocks ranging in size from 0.1 to more than 10 meters and are composed of highly fractured phyllite, slate, and chert from the Phyllite and Chert of Hite Cove (Bateman and Krauskopf, 1987). The purpose of this report is to assess the hazard posed by the Ferguson rockslide by simulating the runout and deposition of a portion of the slide if rapid failure occurs. As discussed by Gallegos and DeGraf (2006), a runout analysis is needed to delineate slide hazards. The report is restricted to calculations of potential runout and does not address the likelihood of rapid failure. Based on discussions with Allan Gallegos (USFS), two end-member initial slide volumes were chosen: (1) the toe of the slide along boundaries defined by Tim Beck (CALTRANS) in (Beck, 2006), and (2) the entire sliding rock mass, again along boundaries defined by Tim Beck. The simulated runout of these volumes during rapid failure uses granular flow mechanics developed by Iverson (1997) and the model developed by Denliner and Iverson, (2004). This model has been thoroughly tested against experimental data and provides plausible, defensible results.

  20. Archive of single-beam bathymetry data collected during USGS cruise 07CCT01 nearshore of Fort Massachusetts and within Camille Cut, West and East Ship Islands, Gulf Islands National Seashore, Mississippi, July 2007

    USGS Publications Warehouse

    DeWitt, Nancy T.; Flocks, James G.; Reynolds, B.J.; Hansen, Mark

    2012-01-01

    identifier to each cruise or field activity. For example, 07CCT01 tells us the data were collected in 2007 for the Coastal Change and Transport (CCT) study and the data were collected during the first (01) field activity for that project in that calendar year. Refer to http://walrus.wr.usgs.gov/infobank/programs/html/definition/activity.html for a detailed description of the method used to assign the field activity ID. Data were collected using a 26-foot (ft) Glacier Bay catamaran. The single-beam transducers were sled mounted on a rail attached between the catamaran hulls. Navigation was acquired using HYPACK, Inc., Hypack version 4.3a.7.1 and differentially corrected using land-based GPS stations. See the digital FACS equipment log for details about the acquisition equipment used. Raw datasets were stored digitally and processed systematically using NovAtel's Waypoint GrafNav version 7.6, SANDS version 3.7, and ESRI ArcGIS version 9.3.1. For more information on processing refer to the Equipment and Processing page.

  1. Exposure history and terrestrial ages of ordinary chondrites from the Dar al Gani region, Libya

    NASA Astrophysics Data System (ADS)

    Welten, K. C.; Nishiizumi, K.; Finkel, R. C.; Hillegonds, D. J.; Jull, A. J. T.; Franke, L.; Schultz, L.

    2004-03-01

    these soils due to deflation during more arid periods, such as the current one, which started ~3000 years ago. Finally, based on the 26Al/21Ne and 10Be/21Ne systematics in 16 DaG meteorites, we derived more reliable estimates of the 10Be/21Ne production rate ratio, which seems more sensitive to shielding than was predicted by the semi-empirical model of Graf et al. (1990) but less sensitive than was predicted by the purely physical model of Leya et al. (2000).

  2. Femoropopliteal bypass vs percutaneous transluminal angioplasty and stenting in treatment of peripheral artery diseases of infrainquinal segment - short-term results.

    PubMed

    Cvetanovski, M V; Jovev, S; Cvetanovska, M; Blazevski, B; Colanceski, R; Andreevska, T; Gramatnikovski, N; Kartalov, A

    2009-07-01

    (Full text is available at http://www.manu.edu.mk/prilozi). Critical limb ischaemia is a result of occlusive arterial disease in the infrainquinal segment and is a major indication for arterial revascularization, which implies a femoropopliteal bypass procedure or an interventional procedure - stent graf notting of the occluded segment. Although indications for both techniques are clearly defined, there are still controversies. Thus, the aim of this study was to determine short-term results in patients treated with these two treatment modalities. In the period between 2002 and 2008 a total of 70 patients with occlusive arte notrial diseases of the low extremity were analysed. In 50 out of 70 patients a femo notro notpopliteal bypass was made. Of these, in 30 (60%) patients PTFE material was used and in 20 (40%) patients an autologous saphenous vein graft was used. The other group comprised 20 patients who underwent stenting. In patients treated with surgical revas notcularization, the major indication for surgery was occlusive arterial disease in: stage II - in 10 patients (20%), stage III - in 5 patients (10%), stage IV - in 25 patients (50%) and the remaining 10 patients (20%) had subacute ischaemia. Arteriography showed three crural patent tributaries in 18% of the patients, two patent crural tributaries in 40% of the patients and one crural patent tributary in 32% of the patients. There were no significant differences concerning indications and arteriographic findings between the two subgroups. The follow-up period lasted for 6 months and the patency rate was 85% (17) for venous bypass, 11 (64.6%) - short-segment lesions (< 4 cm) and 6 (35.3%) lon notger segment lesions (> 4 cm) versus 76.5% (23) for PTFE graft (p < 0.05), of which 13 (56.5%) were short-segment (<4 cm) and 10 (43.5%) longer segment lesions (> 4 cm). The following results were obtained for the second group of patients: initially successful stents in 85%; failure in 15% or 2 patients; technical

  3. Mesospheric electron detachment and LORE recovery times

    NASA Astrophysics Data System (ADS)

    Gordillo-Vazquez, Francisco J.; Haldoupis, Christos; Luque, Alejandro

    2015-04-01

    early VLF events associated to sprites [4], [5]. [1] Haldoupis, C., M. Cohen, E. Arnone, B. Cotts, and S. Dietrich (2013), Step-like and long-recovery early VLF perturbations caused by EM pulses radiated by powerful ± CG lightning discharges, J. Geophys. Res., 118, doi: 10.1002/jgra-50489. [2] Salut, M.M., M. B. Cohen, M. A. M. Ali, K. L. Graf, B. R. T. Cotts and S. Kumar (2013), On the relationship between lightning peak current and early VLF perturbations, J. Geophys. Res. Space Physics, 118, doi: 10.1002/2013JA019087 [3] Inan, U. S., and W. A. Sampson (1996), Space-time structure of optical flashes and ionization changes produced by lighting-EMP, Geophys. Res. Lett., 23, 2, 133-136. [4] Mika, A., and C. Haldoupis (2008), VLF studies during TLE observations in Europe: A summary of new findings, Space Sci. Rev., 137, 489-510, doi: 10.1007/s11214008-9382-8. [5] Inan, U. S., S. A. Cummer, and R. A. Marshall (2010), A survey of ELF/VLF research of lightning-ionosphere interactions and causative discharges, J. Geophys. Res., 115, A00E36, doi: 10.1029/2009JA014775.

  4. The impact of mixing lithologies in clast shape measurements on its discriminatory power - a case study from a temperate Alpine glacier

    NASA Astrophysics Data System (ADS)

    Lukas, S.; Coray, S.; Graf, A.; Schlüchter, C.

    2009-04-01

    power. Therefore, at each locality 50 clasts of the same lithology should be measured to allow a clear distinction of different transport paths. References Benn DI, Ballantyne CK. 1994. Reconstructing the transport history of glacigenic sediments: a new approach based on the co-variance of clast shape indices. Sedimentary Geology 91: 215-227. Bennett MR, Hambrey MJ, Huddart D. 1997. Modification of clast shape in high-arctic glacial environments. Journal of Sedimentary Research 67(3): 550-559. Demir T, Lukas S, Warburton J, Bridgland DR. 2009. A review of clast shape analysis. In: Bridgland DR. (ed). Clast lithological analysis. Technical Guide. Quaternary Research Association: London, in press. Lukas S, Coray S, Graf A, Schlüchter S. 2009. The influence of clast lithology and fluvial reworking on the reliability of clast shape measurements in glacial environments - a case study from a temperate Alpine glacier. In: Bridgland DR. (ed). Clast lithological analysis. Technical Guide. Quaternary Research Association: London, in press.

  5. Rheology of miscible polymer blends with hydrogen bonding

    NASA Astrophysics Data System (ADS)

    Yang, Zhiyi

    Poly(4-vinylphenol) (PVPh) was blended with four different polymers: poly(vinyl methyl ether) (PVME), poly(vinyl acetate) (PVAc), poly(2-vinylpyridine) (P2VP), and poly(4-vinylpyridine) (P4VP) by solvent casting. The miscibility of these four PVPh-based blend systems was investigated using differential scanning calorimetry (DSC) and the composition-dependent glass transition temperature (Tg) was predicted by a thermodynamic theory. The hydrogen bonds between phenolic group in PVPh and ether group, carbonyl group or pyridine group was confirmed by Fourier transform infrared (FTIR) spectroscopy. The fraction of hydrogen bonds was calculated by the Coleman-Graf-Painter association model. Linear dynamic viscoelasticity of four PVPh-based miscible polymer blends with hydrogen bonding was investigated. Emphasis was placed on investigating how the linear dynamic viscoelasticity of miscible polymer blends with specific interaction might be different from that of miscible polymer blends without specific interaction. We have found that an application of time-temperature superposition (TTS) to the PVPh-based miscible blends with intermolecular hydrogen bonding is warranted even when the difference in the component glass transition temperatures is as large as about 200°C, while TTS fails for miscible polymer blends without specific interactions. On the basis of such an observation, we have concluded that hydrogen bonding suppressed concentration fluctuations in PVPh-based miscible blends. It has been found that both the intra-association (self-association) of the phenoxy hydroxyl groups in PVPh and inter-association (intermolecular interactions) between the constituent components have a profound influence on the frequency dependence of dynamic moduli in the terminal region of the PVPh-based miscible blend systems investigated. Hydrogenated functional polynorbornenes (HFPNBs) were synthesized and they were used to investigate the miscibility and rheology of HFPNB

  6. The impact of time-averaged volcanic sulphur emissions on the global cloud condensation nuclei budget in the pre-industrial era

    NASA Astrophysics Data System (ADS)

    Schmidt, Anja; Carslaw, Kenneth; Mann, Graham; Merikanto, Joonas

    2010-05-01

    enhances microphysical processes such as the coagulation of existing and/or entrained particles in upper parts of the atmosphere and in parts of the Southern Hemisphere boundary layer. Our model simulations suggest that volcanoes were a very important source of CCN in the pre-industrial atmosphere. Equatorwards of about 50° volcanoes can sustain CCN concentrations in excess of 50 cm-3, and up to 500 cm-3 over large tropical regions, even when the other main sulphur source (from DMS) is eliminated. Andres, R. J. and Kasgnoc, A. D.: A time-averaged inventory of subaerial volcanic sulfur emissions, J. Geophys. Res., 103, 25 251-25 262, 1998. Dentener, F., Kinne, S., Bond, T., Boucher, O., Cofala, J., Generoso, S., Ginoux, P., Gong, S., Hoelzemann, J. J., Ito, A., Marelli, L., Penner, J. E., Putaud, J. P., Textor, C., Schulz, M., van der Werf, G. R., and Wilson, J.: Emissions of primary aerosol and precursor gases in the years 2000 and 1750 prescribed data-sets for AeroCom, Atmos. Chem. Phys., 6, 4321-4344, 2006. Halmer, M., Schmincke, H., and Graf, H.-F.: The annual volcanic gas input into the atmosphere, in particular into the stratosphere, A global data-set for the past 100 years, J. Volca. Geotherm. Res., 115, 511-528, 2002.

  7. Shielding Effects on 10Be and 26Al in Diogenites

    NASA Astrophysics Data System (ADS)

    Welten, K. C.; Lindner, L.; van der Borg, K.; Loeken, Th.; Schultz, L.

    1995-09-01

    , model calculations were carried out for the 10Be and 26Al pro rates in diogenites [10]. The calculated P10 values agree within 10% with the experimental results, but the P26 values were significantly underestimated for sm medium-sized objects. The similar shielding sensitivity of 10Be and 26Al implies that the 26Al/10Be ra relatively independent of shielding conditions, resulting in an average of 3.2 + (which corresponds to a value of 3.0 for average L-chondrite composition). There the 26Al/10Be ratio is a useful parameter to identify meteorites with unusual ex histories and/or terrestrial histories as will be demonstrated elsewhere [11]. References: [1] Eugster O. (1988) GCA, 52, 1649-1662. [2] Tuniz et al. (1984) GC 1867-1872. [3] Graf Th. et al. (1990) GCA, 54, 2511-2520. [4] Garrison D. H. et (1992) Meteoritics, 27, 371-381. [5] Jilin Consortium Study (1985) EPSL, 72, 247 [6] Vogt S. (1988) Ph.D. thesis, Universit t zu K"ln. [7] Moniot R. K. et al. (1 GCA, 52, 499-504. [8] Hampel W. et al. (1980) GCA, 44, 539-547. [9] Nishiizumi K al. (1989) EPSL, 93, 299-313. [10] Michel R. et al. (1994) Planet. Space Sci., i press.

  8. Chromium-Isotope and iridium-Abundance Measurements for Late Eocene Impact-Derived Spherule Deposits

    NASA Astrophysics Data System (ADS)

    Kyte, F. T.; Shukolyukov, A.; Hildebrand, A. R.; Lugmair, G. W.; Hanova, J.

    2004-05-01

    have sufficiently high epsilon 53 values that it is clear that a large proportion of their Cr is from meteoritic sources. The positive epsilon 53 values and normal terrestrial 54Cr/52Cr ratios for these samples exclude carbonaceous chondrites as a source for the meteoritic component - all measured C-chondrites [1] have excess 54Cr. Our results are generally consistent with an ordinary chondrite source for the Cr. An ordinary chondrite source for the largest of the Late Eocene impacts permits an H chondrite projectile. We note that the 35 Ma spike in cosmic ray exposure ages for the H chondrites [2] could be an indication of a major disrupting collision in the asteroid belt. Simulations indicate that an asteroid shower initiated by disruption of a large asteroid near a Main Belt resonance can have durations as short as 5 m.y. [3], but repeated collisions of disrupted fragments would be necessary to keep dust levels sufficiently high for ~3 m.y. to explain the 3He peak at Massignano. If the Late Eocene impact flux peak in multi-kilometer to dust-sized projectiles is due to an H chondrite asteroid disruption event, several implications for Solar System history follow. [1] Shukolyukov et al. (2003) LPSC XXXIV, abs. 1279; [2] Marti, K. and Graf, T. (1992) Ann. Rev. Earth & Planet. Sci. 20, 221; [3] Zappala et al. (1998) Icarus 134, 176.

  9. Surficial geology of the lower Comb Wash, San Juan County, Utah

    USGS Publications Warehouse

    Longpré, Claire I.

    2001-01-01

    . Most precipitation is monsoonal, convective storms that bring moisture from the Gulf of Mexico beginning in early July and ending by October. Large frontal storms during December and January are responsible for most winter precipitation (Figure 2). The record from U.S. Geological Survey gauging station number 09379000 operated by the BLM from 1959 through 1968 indicates that Comb Wash flows in direct response to precipitation events. Most daily discharge and peak events occur in late July through September, coinciding with high intensity monsoon thunderstorms. Comb Wash supports a variety of vegetation typical of the Great Basin Desert and the northern desert shrub zone as described by Fowler and Koch (1982). On the lower alluvial terraces, bushes and shrubs dominate the vegetation, including: sagebrush (Artemesia tridentata), rabbitbrush (Chrysothamnus nauseosus), fourwing saltbush (Atriplex canescens), winterfat (Eurotia lanata), greasewood (Sarcobatus vermiculatus), and shadscale (Atriplex concertifolia). Juniper trees (Juniperus osteosperma) can be found on the rocky colluvial slopes near Comb Ridge and on the higher terrace near Cedar Mesa. The floodplain contains an abundance of riparian vegetation including cottonwood (Populus fremontii), willow (Salix exigua), and tamarisk (Tamarix ramosissima). Tamarisk is one of 7 non-native species present in the lower Comb Wash watershed. At least seven known species of noxious weeds have invaded the watershed, including Bermuda grass (Cynodon dactylon), field bindweed (Convolvulus avensis), Canada thistle (Cirsium arvense), Russian knapweed (Centaurea repens), tamarisk and camel thorn (Alhagi pseudalhagi). Of these, tamarisk or salt-cedar has most aggressively colonized the southwestern United States, including the San Juan watershed. Graf (1978) estimates that since the late 19th century, tamarisk has spread at a rate of 20 km per year. Tamarisk first appeared in Comb Wash during the mid to early 20th century based on

  10. PREFACE: Strongly correlated electron systems Strongly correlated electron systems

    NASA Astrophysics Data System (ADS)

    Saxena, Siddharth S.; Littlewood, P. B.

    2012-07-01

    modulations in the precursor region of FeGeH Wilhelm, M Baenitz, M Schmidt, C Naylor, R Lortz, U K Rößler, A A Leonov and A N Bogdanov Antiferromagnetism in metals: from the cuprate superconductors to the heavy fermion materialsSubir Sachdev, Max A Metlitski and Matthias Punk Superconducting gap structure of the 115s revisitedF Ronning, J-X Zhu, Tanmoy Das, M J Graf, R C Albers, H B Rhee and W E Pickett Nonmagnetic ground states and phase transitions in the caged compounds PrT2Zn20 (T = Ru, Rh and Ir)T Onimaru, K T Matsumoto, N Nagasawa, Y F Inoue, K Umeo, R Tamura, K Nishimoto, S Kittaka, T Sakakibara and T Takabatake New universality class of quantum criticality in Ce- and Yb-based heavy fermionsShinji Watanabe and Kazumasa Miyake

  11. Novel ideas for maximising dew collection to aid plant establishment to combat desertification and restore degraded dry and arid lands

    NASA Astrophysics Data System (ADS)

    Kotzen, Benz

    2014-05-01

    and numerous studies have been undertaken to investigate past so-called dew collectors and to research the possibilities of using new ones. Most of the historical dew collectors have been disputed as dew collection devices. (Beysens et al 2006, Beysens et al in Kogan and Trahtman 2006, Graf et al 2008.) However, contemporary dew collection has proven possible in those areas that have dew fall. It is generally agreed by researchers, such as Sharan and Beysens in 2007 and Jacobs et al in 2008 after Monteith (1957) that the theoretical maximum dew yield is in the order of 0.8 l/m2/day. Although the exact maximum has never been defined the amounts can yet be significant. However, In most cases the investigations of dew supply in areas where dew is known to precipitate has been undertaken with inclined roof like planar surfaces. However, erecting these planes in remote areas and within difficult terrain makes this kind of collector impractical. Additionally such planar surfaces demand space on the ground which then diminishes the areas of restoration and large collectors require additional plumbing to distribute water to the plants themselves. Thus in order to better supply dew to plants other forms are required. This paper discusses the various ideas and concepts that have been developed for dew collection that have emerged on the market and the novel ideas that have been initiated by the author. The research undertaken investigates biomimetic forms which emulate plant forms such as various cacti and succulents investigating their ability to increase surface area as well as releasing heat like a radiator. Additionally other spiky, needle like forms are investigated as well as animal forms, such as the surface of the Stenocara gracilipes Namibian beetle which collects fog. The research initiated a new strategy for dew collection dividing dew collectors into two types: 1) Passive dew collectors, where nightly collection and delivery is achieved without people, and 2) Semi

  12. Novel ideas for maximising dew collection to aid plant establishment to combat desertification and restore degraded dry and arid lands

    NASA Astrophysics Data System (ADS)

    Kotzen, Benz

    2014-05-01

    and numerous studies have been undertaken to investigate past so-called dew collectors and to research the possibilities of using new ones. Most of the historical dew collectors have been disputed as dew collection devices. (Beysens et al 2006, Beysens et al in Kogan and Trahtman 2006, Graf et al 2008.) However, contemporary dew collection has proven possible in those areas that have dew fall. It is generally agreed by researchers, such as Sharan and Beysens in 2007 and Jacobs et al in 2008 after Monteith (1957) that the theoretical maximum dew yield is in the order of 0.8 l/m2/day. Although the exact maximum has never been defined the amounts can yet be significant. However, In most cases the investigations of dew supply in areas where dew is known to precipitate has been undertaken with inclined roof like planar surfaces. However, erecting these planes in remote areas and within difficult terrain makes this kind of collector impractical. Additionally such planar surfaces demand space on the ground which then diminishes the areas of restoration and large collectors require additional plumbing to distribute water to the plants themselves. Thus in order to better supply dew to plants other forms are required. This paper discusses the various ideas and concepts that have been developed for dew collection that have emerged on the market and the novel ideas that have been initiated by the author. The research undertaken investigates biomimetic forms which emulate plant forms such as various cacti and succulents investigating their ability to increase surface area as well as releasing heat like a radiator. Additionally other spiky, needle like forms are investigated as well as animal forms, such as the surface of the Stenocara gracilipes Namibian beetle which collects fog. The research initiated a new strategy for dew collection dividing dew collectors into two types: 1) Passive dew collectors, where nightly collection and delivery is achieved without people, and 2) Semi

  13. Chapter 3: Evaluating the impacts of carbonaceous aerosols on clouds and climate

    SciTech Connect

    Menon, Surabi; Del Genio, Anthony D.

    2007-09-03

    Any attempt to reconcile observed surface temperature changes within the last 150 years to changes simulated by climate models that include various atmospheric forcings is sensitive to the changes attributed to aerosols and aerosol-cloud-climate interactions, which are the main contributors that may well balance the positive forcings associated with greenhouse gases, absorbing aerosols, ozone related changes, etc. These aerosol effects on climate, from various modeling studies discussed in Menon (2004), range from +0.8 to -2.4 W m{sup -2}, with an implied value of -1.0 W m{sup -2} (range from -0.5 to -4.5 W m{sup -2}) for the aerosol indirect effects. Quantifying the contribution of aerosols and aerosol-cloud interactions remain complicated for several reasons some of which are related to aerosol distributions and some to the processes used to represent their effects on clouds. Aerosol effects on low lying marine stratocumulus clouds that cover much of the Earth's surface (about 70%) have been the focus of most of prior aerosol-cloud interaction effect simulations. Since cumulus clouds (shallow and deep convective) are short lived and cover about 15 to 20% of the Earth's surface, they are not usually considered as radiatively important. However, the large amount of latent heat released from convective towers, and corresponding changes in precipitation, especially in biomass regions due to convective heating effects (Graf et al. 2004), suggest that these cloud systems and aerosol effects on them, must be examined more closely. The radiative heating effects for mature deep convective systems can account for 10-30% of maximum latent heating effects and thus cannot be ignored (Jensen and Del Genio 2003). The first study that isolated the sensitivity of cumulus clouds to aerosols was from Nober et al. (2003) who found a reduction in precipitation in biomass burning regions and shifts in circulation patterns. Aerosol effects on convection have been included in other

  14. Obituary: Michael John Klein, 1940-2005

    NASA Astrophysics Data System (ADS)

    Gulkis, Samuel

    2006-12-01

    Michael John Klein died on 14 May 2005 at home in South Pasadena, California. The cause of death was tongue cancer that metastasized to the lungs. He was a non-smoker. Mike was a passionate radio astronomer, a trusted astronomical observer, an educator and a family man. Mike was born on 19 January 1940 in Ames, Iowa, the son of Florence Marie (Graf) and Fred Michael Klein. His mother was a homemaker, and his father was a banker. Mike had two older sisters, Lois Jean (Klein) Flauher and Marilyn June (Klein) Griffin. In 1962, Mike married his high school sweetheart Barbara Dahlberg, who survives him along with their three children, Kristin Marie (Klein) Shields, Michael John Klein Jr., Timothy Joel Klein, and six grandchildren. Mike developed a love for astronomy early in his life, and credited an early morning, newspaper-delivery route that he had at age twelve, which took him outside well before sunrise. He told family members that as he walked along his route, he stared into the sky and wondered what everything was. He studied sky charts, located stars, and began to understand how the planets shifted their positions relative to the stars each day. Another big influence in Mike's life was his brother in-law, Jim Griffin. Jim helped Mike understand that his passion for science did not have to remain a hobby, but could and should become a career. Jim's encouragement led Mike to attend Iowa State University in Ames, where he earned a BS in electrical engineering in 1962. Mike then started graduate school in electrical engineering at Michigan State, but after one semester transferred to the University of Michigan, Ann Arbor, where he earned an MS (1966) and PhD (1968) in astronomy. His doctoral dissertation, under the direction of Professor Fred Haddock, was based on extensive observations of the planets and examined the physical and thermal properties of planetary atmospheres and surfaces. Mike was awarded a Resident Research Associate position at JPL by the National

  15. PREFACE: ARENA 2006—Acoustic and Radio EeV Neutrino detection Activities

    NASA Astrophysics Data System (ADS)

    Thompson, Lee

    2007-06-01

    , StanfordF. Halzen, Madison J. Learned, HawaiiR. Nahnhauer, Zeuthen A. Rostovtzev, MoscowD. Saltzberg, Los Angeles L. Thompson, SheffieldF. Vannucci, Paris

    Local Organizing Committee

    S. Danaher, NorthumbriaC. Rhodes, Imperial College London
    J. Perkin, SheffieldT. Sloan, Lancaster
    L. Thompson, SheffieldD. Waters, University College London

    Participants

    Joseph Allen, Northumbria University, UK Miguel Ardid, Univ. Polit. de Valencia, Spain
    Thomas Asch, IPE, FZKa, Germany Karl-Heinz Becker, BU Wuppertal, Germany
    Dave Besson, U. of Kansas, USA Simon Bevan, University College London, UK
    Manuel Bou Cabo, Politecnic University Valencia, Spain Sebastian Böser, DESY Zeuthen, Germany
    Antonio Capone, University La Sapienza and INFN, Italy Paula Chadwick, University of Durham, UK
    Masami Chiba, Tokyo Metropolitan University, Japan Amy Connolly, UCLA, USA
    Sean Danaher, Northumbria University, UK Giulia De Bonis, Univ. Rome `La Sapienza', Italy
    Freija Descamps, University of Gent, BelgiumKay Graf, University of Erlangen, Germany
    Andreas Haungs, Forschungszentrum Karlsruhe, Germany Kara Hoffman, University of Maryland, USA
    Stephen Hoover, UCLA, USA Tim Huege, Forschungszentrum Karlsruhe, Germany
    Paula Gina Isar, Forschungszentrum Karlsruhe, Germany Timo Karg, BU Wuppertal, Germany
    Johannes Knapp, University of Leeds, UK Robert Lahmann, University of Erlangen, Germany
    Mark Lancaster

  16. Survey on Cosmogenic 26Al in Lewis Cliff Meteorites

    NASA Astrophysics Data System (ADS)

    Welten, K. C.; Alderliesten, C.; Lindner, L.

    1992-07-01

    al. (1982) Mem. NIPR Spec. Issue 25, 178-187; 2. Evans J.C. and Reeves J.H. (1987) EPSL 82, 223-230; 3. Vogt S. (1990) LPI Tech. Rpt. 90-05, 112-118; 4. Nishizumi K. et al. (1991) Meteoritics 26 (abs.), 380; 5. Graf Th. and Marti K. (1990) Lunar Planet. Sci. XXI, 431-432; 6. Schultz L., Weber H.W. and Begemann F. (1991) GCA 55, 59-66; 7. Benoit P.H. et al. (1990) Ant. J. of the U.S. 25 (Rev.), 47-49.

  17. Noble Gases in the LEW 88663 L7 Chondrite

    NASA Astrophysics Data System (ADS)

    Miura, Y. N.; Sugiura, N.; Nagao, K.

    1995-09-01

    likely terrestrial contamination in origin) rather than chondritic ones seem to be dominant in LEW88663. A K-Ar age of 4.3 +/- 0.2 b.y. is obtained assuming K content of 660 ppm by [9], implying radiogenic ^40Ar is almost retained. Because of low abundance of trapped Xe in the meteorite compared with the abundances in other chondrites, ^244Pu-derived fission Xe could be evaluated more precisely. According to the measured Xe data (for this, three isotope plots such as ^134Xe/^130Xe versus ^136Xe/^130Xe are useful), we conclude that Xe in LEW88663 is the mixture of ^244Pu-derived fission Xe and the terrestrial atmospheric Xe with possibility that a small amount of chondritic Xe is contained. Using the same procedure described in [10], we obtained excess ^136Xe concentration, 1.4 x 10^-12 cm^3STP/g with about 20% uncertainty, of which about 3% is from contribution of ^238U-derived ^136Xe if average U content for L chondrite (14 ppb) is assumed. The calculated Pu abundance of 0.21 ppb is slightly higher than those reported for L chondrites Barwell (0.11 +/- 0.05 ppb [11]) and Marion (0.10+/-0.40 ppb [11]). Acknowledgments: We thank Meteorite Working Group for providing the sample. We are also grateful to Dr. D. Mittlefehldt for showing us his chemical composition data. This work is supported by Research Fellowships of the Japan Society for the Promotion of Science for Young Scientists. References: [1] Mason B. et al. (1992) Antarc. Meteorite Newsletter, 15(2), 30. [2] Mason B. and Marlow R. (1992) Antarc. Meteorite Newsletter, 15(1), 16. [3] Davis A. M. et al. (1993) LPS XXIV, 375-376. [4] Mittlefehldt D. W. (1993) Meteoritics, 28, 401-402. [5] Hervey R. P. (1993) Meteoritics, 28, 360. [6] Eugster O. (1988) GCA, 52, 1649-1662. [7] Marti K. and Graf T.(1992) Annu. Rev. Earth Planet Sci., 20, 221-243. [8] E.g. Marti K. (1967) EPSL, 2, 193-196. [9] Mittlefehldt D. W., personal communication. [10] Miura Y. et al. (1993) GCA, 57, 1857-1866. [11] Hagee B. et al. (1990) GCA, 54

  18. Cosmic-ray Exposure Ages of Meteorites

    NASA Astrophysics Data System (ADS)

    Herzog, G. F.

    2003-12-01

    and Graf (2001), and Eugster (2003) have published general reviews of CRE ages.

  19. Countdown for the Cluster quartet

    NASA Astrophysics Data System (ADS)

    2000-07-01

    then become the official designations of the satellites. Where to witness the first launch in Europe. On 15 July media representatives are invited to cover the launch from various sites in Europe. ESA will broadcast the launch live, with images from Baikonur and ESA's Operations Centre ESOC in Darmstadt, Germany. ESA programme officials and spokespersons will be on hand at each site for interviews. European Press Centre, Germany: Location: ESA/ ESOC Address: Robert-Bosch Strasse 5, Darmstadt, Germany Opening hours: 13:30 -17:30 Contact point: Jocelyne Landeau-Constantin Tel. + 49 6151 90 2696/ 2459 Fax. + 49 6151 90 2961 France Location: ESA Headquarters Address: 8-10 rue Mario Nikis, 75015 Paris, France Opening hours: 13:30- 17:30 Contact point: Anne-Marie Rémondin Tel. + 33 1 5369 7155 Fax. + 33 1 5369 7690 The Netherlands Location: Noordwijk Space Expo Address: Keplerlaan 3, Noordwijk, The Netherlands Opening hours: 13:30 - 17:30 Contact point: Heidi Graf Tel. (till 14/07): + 31 71 565 3006 on launch date at Noordwijk Space Expo, tel.: + 31 71 364 6446 Fax.: + 31 71 565 5728 Italy Location: ESA/ESRIN Address: Via G. Galilei, Frascati (Rome), Italy Opening hours: 13:30- 17:30 Contact point: Franca Morgia Tel. + 39 06 9418 0951 Fax. +39 06 9418 0952 Spain: Location ESA/VILSPA Satellite Station Address: Villafranca del Castillo, Madrid Opening hours: 13:30-17:30 Contact point: Fany Peña Tel + 34 91 813 1211 Fax. +34 91 813 1212 Media representatives wishing to attend the launch event from any of the sites, are kindly requested to fill out the attached reply form and fax it back to the contact point at the site they have chosen. The live launch video transmission will be available in analogue (PAL) and digital (MPEG-2) format, via satellite. There will be different language versions plus clean, international audio. The exact times of the transmission and the satellite parameters will be posted as from 10 July on the Internet at http://television.esa.int. The launch of

  20. PREFACE: XVth International Conference on Calorimetry in High Energy Physics (CALOR2012)

    NASA Astrophysics Data System (ADS)

    Akchurin, Nural

    2012-12-01

    /Saclay Irfu/SPP FRANCAVILLA, Paolo IFAE Barcelona GATAULLIN, Marat California Institute of Technology GATTO, Corrado INFN-Napoli GAUDIO, Gabriella INFN-Pavia GERMANI, Stefano INFN-Perugia Goldenzweig, Pablo University of Rochester GRAF, Norman SLAC National Accelerator Laboratory GROOM, Don Lawrence Berkeley Lab GUARDINCERRI, Elena Los Alamos National Laboratory HAUPTMAN, John Iowa State University HENRIQUES, Ana CERN HUANG, Jin Los Alamos National Laboratory HU, Tao IHEP-Beijing, CAS JIANG, Xiaodong Los Alamos National Laboratory JUI, Charles University of Utah KAPUSTINSKY, Jon Los Alamos National Laboratory KIBILKO, Mark SE Technical Sales, Inc. KIRSCHENMANN, Henning University of Hamburg KISTENEV, Edouard Brookhaven National Laboratory KLIMEK, Pawel Stockholm Universitet KROEGER, Robert University of Mississippi LECOQ, Paul CERN LEE, Sehwook Texas Tech University LEE, Sung-Won Texas Tech University LIVAN, Michele Pavia University LUTZ, Benjamin DESY MAGILL, Stephen Argonne National Laboratory MATHIS, Mark College of William and Mary MATTHEWS, John University of Utah MENKE, Sven Max-Planck-Institut fuer Physik MOULSON, Matthew INFN-Frascati NAGEL, Martin Max-Planck-Institut fuer Physik NAKAMURA, Isamu KEK NEMECEK, Stanislav FZU AVCR Praha NESSI-TEDALDI, Francesca ETH Zurich NOVOTNY, Rainer 2nd Physics Institute, University Giessen OREGLIA, Mark University of Chicago PERLOFF, Alexx Texas A&M University PETYT, David Rutherford Appleton Laboratory RAHMAT, Rahmat University of Mississippi RAMILLI, Marco Hamburg Universitaet ROSIER LEES, Sylvie LAPP- IN2P3-CNRS RUTHERFOORD, John University of Arizona SAKUMA, Tai Texas A&M University SANTIAGO CERQUEIRA, Augusto Federal University of Juiz de Fora SARRA, Ivano INFN-Frascati SEIDEL, Sally University of New Mexico SEIFERT, Frank TU Dresden, Germany SHAMIM, Mansoora University of Oregon SIMON, Frank Max-Planck-Institute for Physics STAFFAN, Paul Wiener Plein and Baus, Corp Dr. STAROVOITOV, Pavel DESY TABARELLI DE FATIS, Tommaso

    1. PREFACE: Stimuli Stimuli

      NASA Astrophysics Data System (ADS)

      Queisser, Hans J.

      2011-01-01

      . Appl. Phys. 40 4994 [17] Ploog K and Graf K 1984 MBE of III-V Compounds (Berlin: Springer) [18] For recent coverage, see Chakraborty T and Pietiläinen P 1995 The Quantum Hall Effect (Berlin: Springer) [19] Werner J H, Kolodinski S and Queisser H J 1993 Phys. Rev. Lett. 72 3851 [20] Yamaguchi M 2002 Physica E 14 84 [21] Queisser H J 2002 Physica E 14 1 and many other contributions in this issue

    2. PREFACE: Classical density functional theory methods in soft and hard matter Classical density functional theory methods in soft and hard matter

      NASA Astrophysics Data System (ADS)

      Haataja, Mikko; Gránásy, László; Löwen, Hartmut

      2010-08-01

      functional theory versus kinetic theory of simple fluids J. Phys.: Condens. Matter 22 364110 [28] Majaniemi S, Provatas N and Nonomura M 2010 Effective model hierarchies for dynamic and static classical density functional theories J. Phys.: Condens. Matter 22 364111 [29] Warshavsky V B and Song X 2010 Perturbation theory for solid-liquid interfacial free energies J. Phys.: Condens. Matter 22 364112 [30] Rosenfeld Y, Schmidt M, Löwen H and Tarazona P 1997 Phys. Rev. E 55 4245 [31] Roth R, Evans R, Lang A and Kahl G 2002 J. Phys: Condens. Matter 14 12063 [32] Tarazona P, Cuesta J A and Martinez-Raton Y 2008 Density Functional Theories of Hard Particle Systems (Springer Lecture Notes in Physics vol 753) (Berlin: Springer) p 247 [33] Roth R 2010 J. Phys: Condens. Matter 22 063102 [34] Schmidt M, Löwen H, Brader J M and Evans R 2000 Phys. Rev. Lett. 85 1934 [35] Schmidt M, Löwen H, Brader J M and Evans R 2002 J. Phys.: Condens. Matter 14 9353 [36] Hansen-Goos H and Mecke K 2009 Phys. Rev. Lett. 102 018302 [37] Esztermann A, Reich H and Schmidt M 2006 Phys. Rev. E 73 011409 [38] Ramakrishnan T V and Yussouff M 1979 Phys. Rev. B 19 2775 [39] Denton A R and Ashcroft N W 1989 Phys. Rev. A 39 4701 [40] Hasegawa M 1994 J. Phys. Soc. Japan 63 2215 [41] Kol A and Laird B B 1997 Mol. Phys. 90 951 [42] van Teeffelen S, Löwen H and Likos C N 2008 J. Phys.: Condens. Matter 20 404217 [43] van Teeffelen S, Hoffmann N, Likos C N and Löwen H 2006 Europhys. Lett. 75 583 [44] Likos C N, Hoffmann N, Löwen H and Louis A A 2002 J. Phys.: Condens. Matter 14 7681 [45] Curtin W A and Ashcroft N W 1986 Phys. Rev. Lett. 56 2775 [46] Likos C N, Németh Z T and Löwen H 1994 J. Phys.: Condens. Matter 6 10965 [47] Poniewierski A and Holyst R 1988 Phys. Rev. Lett. 61 2461 [48] Graf H and Löwen H 1999 J. Phys.: Condens. Matter 11 1435 [49] Bolhuis P and Frenkel D 1997 J. Chem. Phys. 106 666 [50] Frenkel D, Mulder B M and McTague J P 1984 Phys. Rev. Lett. 52 287 [51] Härtel A and Löwen H 2010 J. Phys