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Sample records for argentinean real exchange

  1. Large Devaluations and the Real Exchange Rate

    ERIC Educational Resources Information Center

    Burstein, Ariel; Eichenbaum, Martin; Rebelo, Sergio

    2005-01-01

    In this paper we argue that the primary force behind the large drop in real exchange rates that occurs after large devaluations is the slow adjustment in the prices of nontradable goods and services. Our empirical analysis uses data from five large devaluation episodes: Argentina (2002), Brazil (1999), Korea (1997), Mexico (1994), and Thailand…

  2. Acquiring data in real time in Italy from the Antarctic Seismographic Argentinean Italian Network (ASAIN): testing the global capabilities of the EarthWorm and Antelope software suites.

    NASA Astrophysics Data System (ADS)

    Percy Plasencia Linares, Milton; Russi, Marino; Pesaresi, Damiano; Cravos, Claudio

    2010-05-01

    The Italian National Institute for Oceanography and Experimental Geophysics (Istituto Nazionale di Oceanografia e di Geofisica Sperimentale, OGS) is running the Antarctic Seismographic Argentinean Italian Network (ASAIN), made of 7 seismic stations located in the Scotia Sea region in Antarctica and in Tierra del Fuego - Argentina: data from these stations are transferred in real time to the OGS headquarters in Trieste (Italy) via satellite links provided by the Instituto Antártico Argentino (IAA). Data is collected and archived primarily in Güralp Compress Format (GCF) through the Scream! software at OGS and IAA, and transmitted also in real time to the Observatories and Research Facilities for European Seismology (ORFEUS). The main real time seismic data acquisition and processing system of the ASAIN network is based on the EarthWorm 7.3 (Open Source) software suite installed on a Linux server at the OGS headquarters in Trieste. It runs several software modules for data collection, data archiving, data publication on dedicated web servers: wave_serverV, Winston Wave Server, and data analysis and realtime monitoring through Swarm program. OGS is also running, in close cooperation with the Friuli-Venezia Giulia Civil Defense, the North East (NI) Italy seismic network, making use of the Antelope commercial software suite from BRTT as the main acquisition system. As a test to check the global capabilities of the Antelope software suite, we also set up an instance of Antelope acquiring data in real time from both the regional ASAIN seismic network in Antarctica and a subset of the Global Seismic Network (GSN) funded by the Incorporated Research Institution for Seismology (IRIS). The facilities of the IRIS Data Management System, and specifically the IRIS Data Management Center, were used for real time access to waveform required in this study. The first tests indicated that more than 80% of the earthquakes with magnitude M>5.0 listed in the Preliminary Determination

  3. Real prices from spot foreign exchange market

    NASA Astrophysics Data System (ADS)

    Petroni, Filippo; Serva, Maurizio

    2004-12-01

    In this work we discuss the problem of price definition when using high frequency foreign exchange data. If one uses the spot mid price a strong autocorrelation of returns, at one lag, is found which is only due to microstructure effect and does not capture the real behavior of price dynamics. This autocorrelation increases the intraday volatility estimated from this type of data. To solve this problem we introduce an algorithm which is able, by using the no-arbitrage principle, of eliminating every microstructure effects.

  4. 78 FR 49484 - Exchange of Air Force Real Property for Non-Air Force Real Property

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-14

    ... Department of Air Force Exchange of Air Force Real Property for Non-Air Force Real Property SUMMARY: Notice identifies excess Federal real property under administrative jurisdiction of the United States Air Force it... under the administrative jurisdiction of the Air Force. FOR FURTHER INFORMATION CONTACT: Mr....

  5. Genomic continuity of Argentinean Mennonites.

    PubMed

    Pardo-Seco, Jacobo; Llull, Cintia; Berardi, Gabriela; Gómez, Andrea; Andreatta, Fernando; Martinón-Torres, Federico; Toscanini, Ulises; Salas, Antonio

    2016-11-08

    Mennonites are Anabaptist communities that originated in Central Europe about 500 years ago. They initially migrated to different European countries, and in the early 18(th) century they established their first communities in North America, from where they moved to other American regions. We aimed to analyze an Argentinean Mennonite congregation from a genome-wide perspective by way of investigating >580.000 autosomal SNPs. Several analyses show that Argentinean Mennonites have European ancestry without signatures of admixture with other non-European American populations. Among the worldwide datasets used for population comparison, the CEU, which is the best-subrogated Central European population existing in The 1000 Genome Project, is the dataset showing the closest genome affinity to the Mennonites. When compared to other European population samples, the Mennonites show higher inbreeding coefficient values. Argentinean Mennonites show signatures of genetic continuity with no evidence of admixture with Americans of Native American or sub-Saharan African ancestry. Their genome indicates the existence of an increased endogamy compared to other Europeans most likely mirroring their lifestyle that involve small communities and historical consanguineous marriages.

  6. Genomic continuity of Argentinean Mennonites

    PubMed Central

    Pardo-Seco, Jacobo; Llull, Cintia; Berardi, Gabriela; Gómez, Andrea; Andreatta, Fernando; Martinón-Torres, Federico; Toscanini, Ulises; Salas, Antonio

    2016-01-01

    Mennonites are Anabaptist communities that originated in Central Europe about 500 years ago. They initially migrated to different European countries, and in the early 18th century they established their first communities in North America, from where they moved to other American regions. We aimed to analyze an Argentinean Mennonite congregation from a genome-wide perspective by way of investigating >580.000 autosomal SNPs. Several analyses show that Argentinean Mennonites have European ancestry without signatures of admixture with other non-European American populations. Among the worldwide datasets used for population comparison, the CEU, which is the best-subrogated Central European population existing in The 1000 Genome Project, is the dataset showing the closest genome affinity to the Mennonites. When compared to other European population samples, the Mennonites show higher inbreeding coefficient values. Argentinean Mennonites show signatures of genetic continuity with no evidence of admixture with Americans of Native American or sub-Saharan African ancestry. Their genome indicates the existence of an increased endogamy compared to other Europeans most likely mirroring their lifestyle that involve small communities and historical consanguineous marriages. PMID:27824108

  7. Fock-exchange for periodic structures in the real-space formalism and the KLI approximation.

    PubMed

    Natan, Amir

    2015-12-21

    The calculation of Fock-exchange interaction is an important task in the computation of molecule and solid properties. In this work we describe how we implement the Fock exchange in the real-space formalism using the KLI approximation for the OEP equation for 3D periodic systems. The implementation is demonstrated within the PARSEC real-space pseudopotential code that uses a discrete uniform grid and norm conserving pseudopotentials for the ionic potentials.

  8. Genetic structure of Argentinean hexaploid wheat germplasm

    PubMed Central

    Vanzetti, Leonardo S.; Yerkovich, Nadia; Chialvo, Eugenia; Lombardo, Lucio; Vaschetto, Luis; Helguera, Marcelo

    2013-01-01

    The identification of genetically homogeneous groups of individuals is an ancient issue in population genetics and in the case of crops like wheat, it can be valuable information for breeding programs, genetic mapping and germplasm resources. In this work we determined the genetic structure of a set of 102 Argentinean bread wheat (Triticum aestivum L.) elite cultivars using 38 biochemical and molecular markers (functional, closely linked to genes and neutral ones) distributed throughout 18 wheat chromosomes. Genetic relationships among these lines were examined using model-based clustering methods. In the analysis three subpopulations were identified which correspond largely to the origin of the germplasm used by the main breeding programs in Argentina. PMID:24130447

  9. Historical changes in US dollar exchange rate and real value of oil

    SciTech Connect

    DeMis, W.D.

    1996-12-31

    Oil prices relative to world currencies are now at unprecedented lows, as shown by a price analysis that incorporates the effect of US dollar exchange rates on the value of oil. A commodity-based analysis corroborates this exchange-rate analysis. The value of oil today on world markets is even below its 1969 level (the nadir of the previous oil bust). The inflation-corrected price of oil (using the producer price index) in the US has increased 130% since 1969. However, the US dollar has lost over 40% of its value relative to G-7 currencies since abandonment of the Bretton Woods agreement in 1971. Therefore, the real value of oil an international markets is 20% below its 1969 level. Since 1988 alone, the dollar has lost 16% relative to the G-7 currencies. Oil producing countries are taking extreme revenue cuts caused by the eroding US dollar.

  10. Historical changes in US dollar exchange rate and real value of oil

    SciTech Connect

    DeMis, W.D. )

    1996-01-01

    Oil prices relative to world currencies are now at unprecedented lows, as shown by a price analysis that incorporates the effect of US dollar exchange rates on the value of oil. A commodity-based analysis corroborates this exchange-rate analysis. The value of oil today on world markets is even below its 1969 level (the nadir of the previous oil bust). The inflation-corrected price of oil (using the producer price index) in the US has increased 130% since 1969. However, the US dollar has lost over 40% of its value relative to G-7 currencies since abandonment of the Bretton Woods agreement in 1971. Therefore, the real value of oil an international markets is 20% below its 1969 level. Since 1988 alone, the dollar has lost 16% relative to the G-7 currencies. Oil producing countries are taking extreme revenue cuts caused by the eroding US dollar.

  11. Real Time Alert System: A Disease Management System Leveraging Health Information Exchange

    PubMed Central

    Anand, Vibha; Sheley, Meena E.; Xu, Shawn; Downs, Stephen M.

    2012-01-01

    Background Rates of preventive and disease management services can be improved by providing automated alerts and reminders to primary care providers (PCPs) using of health information technology (HIT) tools. Methods: Using Adaptive Turnaround Documents (ATAD), an existing Health Information Exchange (HIE) infrastructure and office fax machines, we developed a Real Time Alert (RTA) system. RTA is a computerized decision support system (CDSS) that is able to deliver alerts to PCPs statewide for recommended services around the time of the patient visit. RTA is also able to capture structured clinical data from providers using existing fax technology. In this study, we evaluate RTA’s performance for alerting PCPs when their patients with asthma have an emergency room visit anywhere in the state. Results: Our results show that RTA was successfully able to deliver “just in time” patient-relevant alerts to PCPs across the state. Furthermore, of those ATADs faxed back and automatically interpreted by the RTA system, 35% reported finding the provided information helpful. The PCPs who reported finding information helpful also reported making a phone call, sending a letter or seeing the patient for follow up care. Conclusions: We have successfully demonstrated the feasibility of electronically exchanging important patient related information with the PCPs statewide. This is despite a lack of a link with their electronic health records. We have shown that using our ATAD technology, a PCP can be notified quickly of an important event such as a patient’s asthma related emergency room admission so further follow up can happen in near real time. PMID:23569648

  12. Understanding of Gender Stability and Constancy in Argentinean Children.

    ERIC Educational Resources Information Center

    De Lisi, Richard; Gallagher, Ann M.

    1991-01-01

    Investigated the understanding of gender stability on the part of Argentinean children aged three to nine years. Children were asked to explain effects of time, psychological trait, situation, and physical attribute transformations on their own gender and the gender of another child of same sex and one of opposite sex. Judgments of gender…

  13. Future Time Perspective and Motivational Categories in Argentinean Adolescents

    ERIC Educational Resources Information Center

    Vazquez, Stella Maris; Rapetti, Maria Virginia

    2006-01-01

    This study is based on a sample of 332 Argentinean teenagers in their last year of secondary school. In the context of the relational theory of motivation, an attempt is made to determine the motivational categories best predicting Future Time Perspective (FTP) extension. The influence of the sex, locus of control, social class, and school ethos…

  14. EXCHANGE

    SciTech Connect

    Boltz, J.C.

    1992-09-01

    EXCHANGE is published monthly by the Idaho National Engineering Laboratory (INEL), a multidisciplinary facility operated for the US Department of Energy (DOE). The purpose of EXCHANGE is to inform computer users about about recent changes and innovations in both the mainframe and personal computer environments and how these changes can affect work being performed at DOE facilities.

  15. Real Space Renormalization Group Study of the S=1/2 XXZ Chains with Fibonacci Exchange Modulation

    NASA Astrophysics Data System (ADS)

    Hida, Kazuo

    2004-08-01

    Ground state properties of the S=1/2 antiferromagnetic XXZ chain with Fibonacci exchange modulation are studied using the real space renormalization group method for strong modulation. The quantum dynamical critical behavior with a new universality class is predicted in the isotropic case. Combining our results with the weak coupling renormalization group results by Vidal et al., the ground state phase diagram is obtained.

  16. Pulling back the covers: technical lessons of a real-world health information exchange.

    PubMed

    Zafar, Atif; Dixon, Brian E

    2007-01-01

    Several nations and local communities are striving to achieve widespread, secure exchange of clinical data between various health care providers and public health organizations. Most of the literature on health information exchange focuses on the financial, political, and privacy aspects of these initiatives. Perhaps just as important are the technical and organizational factors that have influenced development of data exchange methods and results. One mature network in the Midwestern United States has had success in establishing consistent, secure exchange of clinical data for more than ten years. Presented here are the technical lessons learned and design decisions made from this initiative with the hope that they can be used by others striving to connect disparate clinical information systems for the improvement of health care quality and safety.

  17. Review of the Argentinean species of Pseudomicrocara Armstrong (Coleoptera: Scirtidae).

    PubMed

    Libonatti, María Laura; Ruta, Rafał

    2013-01-01

    The Pseudomicrocara Armstrong from Argentina are reviewed. In total, seven species are present: Pseudomicrocara angusta sp. nov., P. antarctica (Fairmaire) comb. nov., P hieroglyphica sp. nov., P. inflexipenis sp. nov., P livida (Fabricius), P. obliquata (Solier) comb. nov., and P patagonica (Curtis) comb. nov. New provincial records are provided for several species. Pseudomicrocara obliquata, previously known only from Chile, is recorded from Argentina for the first time. Illustrations of habitus and genitalia as well as distributional data for all Argentinean species of Pseudomicrocara are provided.

  18. Improving real-time measurement of H/D exchange using a FTIR biospectroscopic probe.

    PubMed

    Carmona, Pedro; Rodríguez-Casado, Arantxa; Molina, Marina

    2009-02-01

    We describe the improvement of a novel approach to investigating hydrogen/deuterium (H/D) exchange kinetics in biomolecules using transmission infrared spectroscopy. The method makes use of a Fourier transform infrared spectrometer coupled with a microdialysis flow cell to determine exchange rates of labile hydrogens. With this cell system, the monitoring of exchange reactions has been studied here as a function of some cell characteristics such as: (a) dialysis membrane surface contacting both the H(2)O and D(2)O compartments; (b) molecular cutoff of dialysis membrane; and (c) distance between the cell-filling holes. The best improvement has been obtained by increasing the dialysis membrane surface followed by increase of molecular cutoff. However, not significant differences were found using various distances between filling holes. The fastest exchange rate which can be measured with the cell system used here is found to be k = 0.41 +/- 0.02 min(-1), that is, about threefold greater than the one got in a previous work. This microdialysis flow cell has been used here for the study of H/D exchange in nucleic acids with subsequent structural analysis by 2D correlation spectroscopy.

  19. PERSONALITY ASSESSMENT INVENTORY: PSYCHOMETRIC ANALYSES OF ITS ARGENTINEAN VERSION.

    PubMed

    Stover, Juliana B; Solano, Alejandro Castro; Liporace, Mercedes Fernández

    2015-12-01

    This psychometric analysis of the Argentinean version of the Personality Assessment Inventory employed a convenience sample of 998 non-clinical adults from Buenos Aires, Argentina, stratified by sex and age (50% men; M age = 40.4 yr., SD = 16.8; 50% women; M age = 40.7 yr., SD = 17.4; 69% were employed). For a criterion validity study, a second sample of 394 students at the University of Buenos Aires was selected (47% men; M age = 24 yr., SD = 3.7; 53% women; M age = 23.6 yr., SD = 3.4). Cronbach's αs ranged from .60 to .86, indicating adequate internal consistency. Following American, German, and Spanish studies, a first analysis on the 22 scales obtained a five-factor solution (65.3% of total variance), and a second analysis on 11 clinical scales isolated a two-factor solution (69.3% of total variance). Correlations with the Symptom Checklist-90-R provided support for criterion validity. Most of the scales and subscales showed sex differences and differences between American and Argentinean samples. Future research must add other psychometric indicators.

  20. Antioxidant activity and phenolic profiles of the wild currant Ribes magellanicum from Chilean and Argentinean Patagonia.

    PubMed

    Jiménez-Aspee, Felipe; Thomas-Valdés, Samanta; Schulz, Ayla; Ladio, Ana; Theoduloz, Cristina; Schmeda-Hirschmann, Guillermo

    2016-07-01

    The Patagonian currant Ribes magellanicum is highly valued due to its pleasant flavor and sweet taste. The aim of this study was to characterize its constituents and to assess their antioxidant and cytoprotective properties. For the fruit phenolic-enriched extract (PEE), total phenolics (TP), total flavonoids (TF), and antioxidant activity (DPPH, Ferric reducing antioxidant power (FRAP), and Trolox equivalent antioxidant activity (TEAC)) were determined. Argentinean samples presented better activity in the DPPH and FRAP assays. Best cytoprotection against oxidative stress induced by H2O2 in AGS cells was found in one Argentinean sample at 500 μg mL(-1) (65.7%). HPLC MS/MS analysis allowed the tentative identification of 59 constituents, including eight anthocyanins, 11 conjugates of caffeic-, ferulic-, and coumaric acid, and 38 flavonoids, most of them quercetin and kaempferol derivatives. Argentinean samples showed a more complex pattern of anthocyanins, hydroxycinnamic acids (HCA), and flavonoids. Cyanidin rhamnoside hexoside and cyanidin hexoside were the main anthocyanins, accounting for 35 and 55% for the Argentinean and 60 and 27% for the ripe Chilean fruits. HCA content was about three times higher in Argentinean samples. The phenolic profiles of Chilean and Argentinean Ribes magellanicum show remarkable differences in chemical composition with higher HCA and flavonoid content in Argentinean samples.

  1. On the accuracy of calculating the exchange part of the real heavy ion potential

    NASA Astrophysics Data System (ADS)

    Ismail, M.; Osman, M. M.; Salah, F.

    1996-02-01

    In the present work, we test the validity of replacing the non-diagonal density matrix appearing in the exchange part of the nucleus-nucleus optical potential by an approximation based on the density matrix expansion used frequently in the nuclear structure calculations. We have found that for the recently derived BDM3Y nucleon-nucleon force the DME may produce a maximum error more than 20% in the nucleus-nucleus potential.

  2. Accuracy of calculating the exchange part of the real alpha-nucleus potential

    NASA Astrophysics Data System (ADS)

    Ismail, M.; Salah, F.; Osman, M. M.

    1996-12-01

    In the present work, we test the validity of replacing the nondiagonal matrix ρ(r-->,r-->') appearing in the exchange part of the α-nucleus optical potential by an approximation based on the density matrix expansion (DME) used frequently in nuclear structure calculations. We have found that for the recently derived BDM3Y nucleon-nucleon force the DME may produce a maximum error more than 29% in the α-nucleus potential.

  3. Two new species of Neotyphloceras (Siphonaptera: Ctenophthalmidae) from Argentinean Patagonia.

    PubMed

    Sanchez, Juliana; Lareschi, Marcela

    2014-03-27

    Two new species of Neotyphloceras Rothschild, parasites of sigmodontine rodents from Argentinean Patagonia, are described and illustrated: N. crackensis n. sp. and N. pardinasi n. sp. These species are compared with their morphologically closest relatives. Males are characterized by the shape of the upper lobe of the fixed process of clasper; the shape and chaetotaxy of the distal arm of sternum IX and by the shape of the crochet of the aedeagus; females by the contour of the distal margin of sternum VII. Neotyphloceras pardinasi n. sp. is reported from western Chubut Province, while N. crackensis n. sp. is known from the eastern regions of Chubut and Santa Cruz Provinces. With these reports, the geographical distribution of Neotyphloceras is extended to eastern Patagonia. A key to the species and subspecies of Neotyphloceras is provided.

  4. Personality disorders, depression, and coping styles in Argentinean bulimic patients.

    PubMed

    Gongora, Vanesa C; van der Staak, Cees P F; Derksen, Jan J L

    2004-06-01

    This study investigates the coping styles of bulimic patients with personality disorders (PDs) and the effects of the level of depression on the relations between PDs and coping. The sample consisted of 75 Argentinean bulimic outpatients engaged in treatment. Patients completed the SCID II (Structural Interview for DSM IV-Personality Disorders), COPE (Coping Inventory), and the SCL-90-R (Symptom Checklist-90-Revised). No differences in the coping styles of bulimic patients with or without a PD were found. However, when three specific PDs were considered-Avoidant, Obsessive-Compulsive, or Borderline PDs-clear differences in the coping styles of the bulimics were found. However, the differences disappeared when depression was controlled. Regarding the severity of the three specific PDs, coping styles were only found to be associated with the Avoidant PD. Depression showed to affect the relations between coping styles and two specific PDs-Avoidant and Borderline PDs-in bulimic patients.

  5. Stomatal design principles for gas exchange in synthetic and real leaves

    NASA Astrophysics Data System (ADS)

    Jensen, Kaare H.; Haaning, Katrine; Boyce, C. Kevin; Zwieniecki, Maciej

    2016-11-01

    Stomata are portals in plant leaves that control gas exchange for photosynthesis, a process fundamental to life on Earth. Gas fluxes and plant productivity depend on external factors such as light, water, and CO2 availability and on geometric properties of the stomata pores. The link between stomata geometry and environmental factors have informed a wide range of scientific fields - from agriculture to climate science, where observed variations in stomata size and density is used to infer prehistoric atmospheric CO2 content. However, the physical mechanisms and design principles responsible for major trends in stomatal patterning, are not well understood. Here we use a combination of biomimetic experiments and theory to rationalize the observed changes in stomatal geometry. We show that the observed correlations between stomatal size and density are consistent with the hypothesis that plants favor efficient use of space and maximum control of dynamic gas conductivity, and - surprisingly - that the capacity for gas exchange in plants has remained constant over at least the last 325 million years. Our analysis provides a new measure to gauge the relative performance of species based on their stomatal characteristics. Supported by the Carlsberg Foundation (2013-01-0449), VILLUM FONDEN (13166) and the National Science Foundation (EAR-1024041).

  6. EDI and ERP: a real-time framework for healthcare data exchange.

    PubMed

    Woodside, Joseph M

    2007-06-01

    A framework is presented for Enterprise Resource Planning (ERP) and Electronic Data Interchange (EDI) in the healthcare industry. As the total cost of healthcare continues to rise and competitive pressures increase, the ability to reduce expenses while at the same time improving overall business characteristics, create an opportunity and necessity for technology usage. The framework addresses current barriers of EDI setup such as cost and flexibility along with ERP communication between entities. A prototype system is created to show feasibility of recent technology improvements and generate a proof of concept for the real-time framework.

  7. The mechanism of monensin-mediated cation exchange based on real time measurements.

    PubMed

    Nachliel, E; Finkelstein, Y; Gutman, M

    1996-12-04

    Monensin is an ionophore that supports an electroneutral ion exchange across the lipid bilayer. Because of this, under steady-state conditions, no electric signals accompany its reactions. Using the Laser Induced Proton Pulse as a synchronizing event we selectively acidify one face of a black lipid membrane impregnated by monensin. The short perturbation temporarily upsets the acid-base equilibrium on one face of the membrane, causing a transient cycle of ion exchange. Under such conditions the molecular events could be discerned as a transient electric polarization of the membrane lasting approx. 200 microseconds. The proton-driven chemical reactions that lead to the electric signals had been reconstructed by numeric integration of differential rate equations which constitute a maximalistic description of the multi equilibria nature of the system (Gutman, M. and Nachliel, E. (1989) Electrochim. Acta 34, 1801-1806). The analysis of the reactions reveals that the ionic selectivity of the monensin (H+ > Na+ > K+) is due to more than one term. Besides the well established different affinity for the various cations, the selectivity is also derived from a large difference in the rates of cross membranal diffusivities (MoH > MoNa > MoK), which have never been detected before. (v) Quantitative analysis of the membrane's crossing rates of the three neutral complexes reveals a major role of the membranal dipolar field in regulating ion transport. The diffusion of MoH, which has no dipole moment, is hindered only by the viscose drag. On the other hand, the dipolar complexes (MoNa and MoK) are delayed by dipole-dipole interaction with the membrane. (vi) Comparison of the calculated dipoles with those estimated for the crystalline conformation of the [MoNa(H2O)2] and [MoK(H2O)2] complexes reveals that the MoNa may exist in the membrane at its crystal configuration, while the MoK definitely attains a structure having a dipole moment larger than in the crystal.

  8. Flow cytometry for real-time measurement of guanine nucleotide binding and exchange by Ras-like GTPases.

    PubMed

    Schwartz, Samantha L; Tessema, Mathewos; Buranda, Tione; Pylypenko, Olena; Rak, Alexey; Simons, Peter C; Surviladze, Zurab; Sklar, Larry A; Wandinger-Ness, Angela

    2008-10-15

    Ras-like small GTPases cycle between GTP-bound active and GDP-bound inactive conformational states to regulate diverse cellular processes. Despite their importance, detailed kinetic or comparative studies of family members are rarely undertaken due to the lack of real-time assays measuring nucleotide binding or exchange. Here we report a bead-based flow cytometric assay that quantitatively measures the nucleotide binding properties of glutathione-S-transferase (GST) chimeras for prototypical Ras family members Rab7 and Rho. Measurements are possible in the presence or absence of Mg(2+), with magnesium cations principally increasing affinity and slowing nucleotide dissociation rates 8- to 10-fold. GST-Rab7 exhibited a 3-fold higher affinity for guanosine diphosphate (GDP) relative to guanosine triphosphate (GTP) that is consistent with a 3-fold slower dissociation rate of GDP. Strikingly, GST-Rab7 had a marked preference for GTP with ribose ring-conjugated BODIPY FL. The more commonly used gamma-NH-conjugated BODIPY FL GTP analogue failed to bind to GST-Rab7. In contrast, both BODIPY analogues bound equally well to GST-RhoA and GST-RhoC. Comparisons of the GST-Rab7 and GST-RhoA GTP binding pockets provide a structural basis for the observed binding differences. In sum, the flow cytometric assay can be used to measure nucleotide binding properties of GTPases in real time and to quantitatively assess differences between GTPases.

  9. REAL WASTE TESTING OF SPHERICAL RESORCINOL-FORMALDEHYDE ION EXCHANGE RESIN

    SciTech Connect

    Nash, C.; Duignan, M.

    2009-10-30

    This report presents data on batch contact and column testing tasks for spherical resorcinol-formaldehyde (sRF) resin. The testing used a non-radioactive simulant of SRS Tank 2F dissolved salt, as well as an actual radioactive waste sample of similar composition, which are both notably high in sodium (6 M). The resin was Microbeads batch 5E-370/641 which had been made on the hundred gallon scale. Equilibrium batch contact work focused on cesium at a temperature of 25 C due to the lack of such data to better benchmark existing isotherm models. Two campaigns were performed with small-scale ion exchange columns, first with Tank 2F simulant, then with actual dissolved salt in the Shielded Cells. An extrapolation of the batch contact results with radioactive waste over-predicted the cesium loaded onto the IX sRF resin bed by approximately 11%. This difference is not unexpected considering uncertainties from measurement and extrapolation and because the ion exchange that occurs when waste flows through a resin bed probably cannot reach the same level of equilibrium as when waste and resin are joined in a long term batch contact. Resin was also characterized to better understand basic chemistry issues such as holdup of trace transition metals present in the waste feed streams. The column tests involved using two beds of sRF resin in series, with the first bed referred to as the Lead column and the second bed as the Lag column. The test matrix included two complete IX cycles for both the simulant and actual waste phases. A cycle involves cesium adsorption, until the resin in the Lead column reaches saturation, and then regenerating the sRF resin, which includes eluting the cesium. Both the simulated and the actual wastes were treated with two cycles of operation, and the resin beds that were used in the Lead and Lag columns of simulant test phase were regenerated and reused in the actual waste test phase. This task is the first to demonstrate the treatment of SRS waste

  10. Persistence and sorption of imazapyr in three Argentinean soils.

    PubMed

    Gianelli, Valeria Rosana; Bedmar, Francisco; Costa, José Luis

    2014-01-01

    Imazapyr is a herbicide widely used for weed control in imidazolinone-tolerant sunflower. Imazapyr has a high potential for leaching into groundwater because it is highly water-soluble, persistent in soil, and only weakly sorbed by soils. There is a lack of information available in Argentina concerning groundwater leaching of imazapyr. Therefore, the objective of the present study was to determine the persistence and sorption of imazapyr in 3 Argentinean soils (Tandil, Anguil, and Cerro Azul sites). The presence and concentration of imazapyr were determined and quantified by ultra-performance liquid chromatography and tandem mass spectrometry. The persistence in soils followed the order: Cerro Azul > Tandil > Anguil, with half-life values of 121 d, 75 d, and 37 d, respectively. The half-life of imazapyr was negatively associated with soil pH and iron and aluminum content, and was positively related to clay content. Imazapyr sorption was found to be well described by the Freundlich isotherm. Soil pH and clay, iron, and aluminum contents were the main factors affecting the sorption of imazapyr. The sorption had a limiting effect on the degradation rate. Under certain conditions, the weak sorption and high persistence may increase the movement of imazapyr in the soil profile and the risk of groundwater pollution.

  11. Relatedness and social organization of coypus in the Argentinean pampas

    USGS Publications Warehouse

    Tunez, J.I.; Guichon, M.L.; Centron, D.; Henderson, A.P.; Callahan, C.; Cassini, M.H.

    2009-01-01

    Behavioural and trapping studies of the social organization of coypus have suggested the occurrence of kin groups and a polygynous mating system. We used 16 microsatellite markers to analyse parentage and relatedness relationships in two populations (J??uregui and Villa Ruiz) in the Argentinean Pampas. At J??uregui, a dominant male monopolized most paternities, leading to a high variance in reproductive success between males and a high level of polygyny. At Villa Ruiz, variance in reproductive success was low among resident males and males were the fathers of zero to four offspring each. For females, no significant differences were found. Two different social groups in each study site were used to assess genetic relatedness within and between groups. These groups were neighbouring at J??uregui but not at Villa Ruiz. At Villa Ruiz, coypus were significantly more related within than between groups, suggesting that behavioural groups were also genetic ones, and adult females were more related within than between groups, as should be expected for kin groups. This relationship was not found at J??uregui. Our results provide support to previous studies based on behavioural and trapping data, which indicate that coypus form social groups and have a polygynous mating system. However, we found differences in social organization between the two populations. This is the first study to determine parentage and/or relatedness in coypus. ?? 2008 The Authors.

  12. Complete genome sequence of an Argentinean isolate of Solenopsis invicta virus 3

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The genome of an Argentinean isolate of Solenopsis invicta virus 3 (SINV-3ArgSF) obtained from the Santa Fe region of Argentina was sequenced in entirety. Assembly of 9 overlapping fragments yielded a consensus genome sequence 10,386 nucleotides long, excluding the poly(A) tail present on the 3' en...

  13. First report of the black gemfish Nesiarchus nasutus (Perciformes: Gempylidae) in Argentinean waters.

    PubMed

    Spath, M C; Delpiani, G; Brunetti, N E; Sakai, M; Figueroa, D E

    2015-05-01

    The gempylid Nesiarchus nasutus is reported for the first time from Argentinean waters, the southernmost occurrence of the species in the Southwestern Atlantic. This suggests that the fluctuating environmental characteristics of the area would be proper for the presence of tropical and subtropical species.

  14. Female Anxiety and Male Depression: Links between Economic Strain and Psychological Aggression in Argentinean Couples

    ERIC Educational Resources Information Center

    Falconier, Mariana K.

    2010-01-01

    A dyadic model of economic strain was applied to the study of anxiety and depression as mediating mechanisms in the economic strain-psychological aggression relation. Data came from self-report questionnaires completed by 143 Argentinean clinical couples. Structural equation modeling analysis indicated that anxiety and depression increased for…

  15. City breathability as quantified by the exchange velocity and its spatial variation in real inhomogeneous urban geometries: an example from central London urban area.

    PubMed

    Panagiotou, Ioannis; Neophytou, Marina K-A; Hamlyn, David; Britter, Rex E

    2013-01-01

    The breathability capacity and its spatial variation within an inhomogeneous urban area is investigated by examining the air flow and the induced flow exchange processes inside a real neighbourhood area of central London. The variation of the exchange velocity (as an index of city breathability) is interpreted in association with the local urban geometrical parameters and hence geometrical inhomogeneity. Numerical studies addressing flow exchange processes in urban areas have addressed so far rather idealised homogeneous geometries (e.g. Hamlyn and Britter, 2005; Salizzoni et al., 2009; Buccolieri et al., 2010; Hang et al., 2009 and 2010). This work analyses the results obtained from a Computational Fluid Dynamics (CFD) simulation study using a Reynolds-Average-Navier-Stokes (RANS) solver to study the flow and induced exchange processes in the area around the Marylebone Road and Gloucester Place intersection modelled at a 1:200 scale, with the wind direction blowing in the direction of the Marylebone street axis. Flow visualisations from the numerical results confirm that the particular building shapes and street canyon geometries determine the shape and size of vortical structures that are present in the flow field and thereby the exchange processes with the flow above. By considering appropriate control volumes enclosing each building, the exchange velocities, U(E), were deduced and found to range between 0.5% and 13% of the characteristic velocity above the urban canopy U(ref), which was referenced at a height 2.5 times of the building height. The range of the exchange velocity coefficient U(E)/U(ref) is higher than that observed in idealised regular cube arrays, mainly due to the enhanced flow mixing associated with the inhomogeneity of the urban geometry and particularly with tall buildings. This work may provide useful insight to urban designers and planners interested in examining the variation of city breathability as a local dynamic morphological parameter

  16. Human immunodeficiency virus/acquired immunodeficiency syndrome prevention in injection drug users and their partners and children: lessons learned in Latin America--the Argentinean case.

    PubMed

    Rossi, Diana; Goltzman, Paula; Cymerman, Pablo; Touzé, Graciela; Weissenbacher, Mercedes

    2003-12-15

    Thirty-nine percent of Argentineans living with acquired immunodeficiency syndrome were infected with human immunodeficiency virus through the injection of drugs. However, it was not until the 1990s that harm reduction programs were created. Research and outreach projects have been developed to identify and interact with the hidden injection drug user (IDU) population. Implementation of rapid assessment and response methodology contributed to the founding of Argentina's first syringe exchange program. Community-based outreach is the appropriate method for working with the impoverished population of Buenos Aires. Seroprevalence studies and focused prevention campaigns targeting IDUs and their sex partners and children have been developed. Collaborations between government and nongovernmental organizations in various cities supported the distribution of prevention and harm reduction messages to 900 IDUs within a 3-month period. Ongoing research, community-based interventions, and collaborative work among different organizations allow for more frequent and more consistent contact with the IDU population of Argentina.

  17. Synthesis and characterization of a new inorganic cation-exchanger-Zr(IV) tungstomolybdate: analytical applications for metal content determination in real sample and synthetic mixture.

    PubMed

    Nabi, Syed Ashfaq; Naushad, Mu; Inamuddin

    2007-04-02

    An amorphous sample of inorganic cation-exchanger Zr(IV) tungstomolybdate was prepared by mixing varying ratios of 0.1M aqueous solution of sodium tungstate and 0.1M aqueous solution of sodium molybdate into 0.1M aqueous solution of zirconium oxychloride at pH 1. This cation-exchanger was found to have a good ion-exchange capacity (2.40 mequiv.g(-1) for Na(+)), high thermal and chemical stability. A tentative structural formula was proposed on the basis of chemical composition, FTIR and thermogravimetric analysis. Distribution coefficients (K(d)) values of metal ions in various solvent systems were determined. Some important and analytically difficult quantitative binary separations viz. Ni(II)-Pb(II), Ni(II)-Zn(II), Ni(II)-Cd(II), Mg(II)-Al(III), etc. were achieved. The practical applicability of the cation-exchanger was demonstrated in the separation of Cu(II)-Zn(II) from a synthetic mixture as well as from real samples of pharmaceutical formulation and brass alloy.

  18. Effect of fermentation on naturally occurring deoxynivalenol (DON) in Argentinean bread processing technology.

    PubMed

    Samar, M M; Neira, M S; Resnik, S L; Pacin, A

    2001-11-01

    The stability of naturally occurring DON was evaluated during the fermentation stage of the bread-making process on a pilot scale. Two different products, French bread and Vienna bread, were prepared with naturally contaminated wheat flour (150 mg kg(-1)) under controlled experimental conditions. Dough was fermented at 30, 40 and 50 degrees C according to standard procedures employed in Argentinean low-technology bakeries. When the dough was fermented at 50 degrees C, the maximum reduction was 56% for the Vienna bread, with French bread being reduced by 41%. DON reduction during bread-making occurs not only in the baker due to thermal decomposition, but also during the fermentation step. The Argentinean traditional bread-making process might reduce DON levels during the fermentation stages if the dough is leavened at temperatures > 30 degrees C.

  19. Outstanding performance of configuration interaction singles and doubles using exact exchange Kohn-Sham orbitals in real-space numerical grid method.

    PubMed

    Lim, Jaechang; Choi, Sunghwan; Kim, Jaewook; Kim, Woo Youn

    2016-12-14

    To assess the performance of multi-configuration methods using exact exchange Kohn-Sham (KS) orbitals, we implemented configuration interaction singles and doubles (CISD) in a real-space numerical grid code. We obtained KS orbitals with the exchange-only optimized effective potential under the Krieger-Li-Iafrate (KLI) approximation. Thanks to the distinctive features of KLI orbitals against Hartree-Fock (HF), such as bound virtual orbitals with compact shapes and orbital energy gaps similar to excitation energies; KLI-CISD for small molecules shows much faster convergence as a function of simulation box size and active space (i.e., the number of virtual orbitals) than HF-CISD. The former also gives more accurate excitation energies with a few dominant configurations than the latter, even with many more configurations. The systematic control of basis set errors is straightforward in grid bases. Therefore, grid-based multi-configuration methods using exact exchange KS orbitals provide a promising new way to make accurate electronic structure calculations.

  20. Outstanding performance of configuration interaction singles and doubles using exact exchange Kohn-Sham orbitals in real-space numerical grid method

    NASA Astrophysics Data System (ADS)

    Lim, Jaechang; Choi, Sunghwan; Kim, Jaewook; Kim, Woo Youn

    2016-12-01

    To assess the performance of multi-configuration methods using exact exchange Kohn-Sham (KS) orbitals, we implemented configuration interaction singles and doubles (CISD) in a real-space numerical grid code. We obtained KS orbitals with the exchange-only optimized effective potential under the Krieger-Li-Iafrate (KLI) approximation. Thanks to the distinctive features of KLI orbitals against Hartree-Fock (HF), such as bound virtual orbitals with compact shapes and orbital energy gaps similar to excitation energies; KLI-CISD for small molecules shows much faster convergence as a function of simulation box size and active space (i.e., the number of virtual orbitals) than HF-CISD. The former also gives more accurate excitation energies with a few dominant configurations than the latter, even with many more configurations. The systematic control of basis set errors is straightforward in grid bases. Therefore, grid-based multi-configuration methods using exact exchange KS orbitals provide a promising new way to make accurate electronic structure calculations.

  1. On the real performance of cation exchange resins in wastewater treatment under conditions of cation competition: the case of heavy metal pollution.

    PubMed

    Prelot, Benedicte; Ayed, Imen; Marchandeau, Franck; Zajac, Jerzy

    2014-01-01

    Sorption performance of cation-exchange resins Amberlite® IRN77 and Amberlite™ IRN9652 toward Cs(I) and Sr(II) has been tested in single-component aqueous solutions and simulated waste effluents containing other monovalent (Effluent 1) or divalent (Effluent 2) metal cations, as well as nitrate, borate, or carbonate anions. The individual sorption isotherms of each main component were measured by the solution depletion method. The differential molar enthalpy changes accompanying the ion-exchange between Cs+ or Sr2+ ions and protons at the resin surface from single-component nitrate solutions were measured by isothermal titration calorimetry and they showed a higher specificity of the two resins toward cesium. Compared to the retention limits of both resins under such idealized conditions, an important depression in the maximum adsorption capacity toward each main component was observed in multication systems. The overall effect of ion exchange process appeared to be an unpredictable outcome of the individual sorption capacities of the two resins toward various cations as a function of the cation charge, size, and concentration. The cesium retention capacity of the resins was diminished to about 25% of the "ideal" value in Effluent 1 and 50% in Effluent 2; a further decrease to about 15% was observed upon concomitant strontium addition. The uptake of strontium by the resins was found to be less sensitive to the addition of other metal components: the greatest decrease in the amount adsorbed was 60% of the ideal value in the two effluents for Amberlite® IRN77 and 75% for Amberlite™ IRN9652. It was therefore demonstrated that any performance tests carried out under idealized conditions should be exploited with much caution to predict the real performance of cation exchange resins under conditions of cation competition.

  2. Development of ANN-based models to predict the static response and dynamic response of a heat exchanger in a real MVAC system

    NASA Astrophysics Data System (ADS)

    Hu, Qinhua; So, Albert T. P.; Tse, W. L.; Ren, Qingchang

    2005-01-01

    This paper presents a systematic approach to develop artificial neural network (ANN) models to predict the performance of a heat exchanger operating in real mechanical ventilation and air-conditioning (MVAC) system. Two approaches were attempted and presented. Every detailed components of the MVAC system have been considered and we attempt to model each of them by one ANN. This study used the neural network technique to obtain a static and a dynamic model for a heat exchanger mounted in an air handler unit (AHU), which is the key component of the MVAC system. It has been verified that almost all of the predicted values of the ANN model were within 95% - 105% of the measured values, with a consistent mean relative error (MRE) smaller than 2.5%. The paper details our experiences in using ANNs, especially those with back-propagation (BP) structures. Also, the weights and biases of our trained-up ANN models are listed out, which serve as good reference for readers to deal with their own situations.

  3. Analysis of D216H polymorphism in Argentinean patients with primary dystonia.

    PubMed

    Caputo, Mariela; Irisarri, Maximiliano; Perandones, Claudia; Alechine, Evguenia; Pellene, Luis Alejandro; Roca, Claudia Uribe; Micheli, Federico E; Corach, Daniel

    2013-06-01

    The D216H polymorphism (rs1801968) in TOR1A has been suggested as a risk factor for developing primary dystonia in German subjects not carrying the deletion c.904-906delGAG (∆GAG). However, this association could not be confirmed in other populations with different ethnic backgrounds. The purpose of this study is to evaluate the D216H polymorphism in an Argentinean cohort of 40 patients with primary dystonia and 200 unrelated control subjects. The authors could observe a significantly higher frequency of the H216 variant in dystonic patients lacking ∆GAG as compared with controls.

  4. Real-time remote monitoring of temperature and humidity within a proton exchange membrane fuel cell using flexible sensors.

    PubMed

    Kuo, Long-Sheng; Huang, Hao-Hsiu; Yang, Cheng-Hao; Chen, Ping-Hei

    2011-01-01

    This study developed portable, non-invasive flexible humidity and temperature microsensors and an in situ wireless sensing system for a proton exchange membrane fuel cell (PEMFC). The system integrated three parts: a flexible capacitive humidity microsensor, a flexible resistive temperature microsensor, and a radio frequency (RF) module for signal transmission. The results show that the capacitive humidity microsensor has a high sensitivity of 0.83 pF%RH(-1) and the resistive temperature microsensor also exhibits a high sensitivity of 2.94 × 10(-3) °C(-1). The established RF module transmits the signals from the two microsensors. The transmission distance can reach 4 m and the response time is less than 0.25 s. The performance measurements demonstrate that the maximum power density of the fuel cell with and without these microsensors are 14.76 mW·cm(-2) and 15.90 mW·cm(-2), with only 7.17% power loss.

  5. Real-Time Remote Monitoring of Temperature and Humidity Within a Proton Exchange Membrane Fuel Cell Using Flexible Sensors

    PubMed Central

    Kuo, Long-Sheng; Huang, Hao-Hsiu; Yang, Cheng-Hao; Chen, Ping-Hei

    2011-01-01

    This study developed portable, non-invasive flexible humidity and temperature microsensors and an in situ wireless sensing system for a proton exchange membrane fuel cell (PEMFC). The system integrated three parts: a flexible capacitive humidity microsensor, a flexible resistive temperature microsensor, and a radio frequency (RF) module for signal transmission. The results show that the capacitive humidity microsensor has a high sensitivity of 0.83 pF%RH−1 and the resistive temperature microsensor also exhibits a high sensitivity of 2.94 × 10−3 °C−1. The established RF module transmits the signals from the two microsensors. The transmission distance can reach 4 m and the response time is less than 0.25 s. The performance measurements demonstrate that the maximum power density of the fuel cell with and without these microsensors are 14.76 mW·cm−2 and 15.90 mW·cm−2, with only 7.17% power loss. PMID:22164099

  6. Analysis of admixture and genetic structure of two Native American groups of Southern Argentinean Patagonia.

    PubMed

    Sala, Andrea; Corach, Daniel

    2014-03-01

    Argentinean Patagonia is inhabited by people that live principally in urban areas and by small isolated groups of individuals that belong to indigenous aboriginal groups; this territory exhibits the lowest population density of the country. Mapuche and Tehuelche (Mapudungun linguistic branch), are the only extant Native American groups that inhabit the Argentinean Patagonian provinces of Río Negro and Chubut. Fifteen autosomal STRs, 17 Y-STRs, mtDNA full length control region sequence and two sets of Y and mtDNA-coding region SNPs were analyzed in a set of 434 unrelated individuals. The sample set included two aboriginal groups, a group of individuals whose family name included Native American linguistic root and urban samples from Chubut, Río Negro and Buenos Aires provinces of Argentina. Specific Y Amerindian haplogroup Q1 was found in 87.5% in Mapuche and 58.82% in Tehuelche, while the Amerindian mtDNA haplogroups were present in all the aboriginal sample contributors investigated. Admixture analysis performed by means of autosomal and Y-STRs showed the highest degree of admixture in individuals carrying Mapuche surnames, followed by urban populations, and finally by isolated Native American populations as less degree of admixture. The study provided novel genetic information about the Mapuche and Tehuelche people and allowed us to establish a genetic correlation among individuals with Mapudungun surnames that demonstrates not only a linguistic but also a genetic relationship to the isolated aboriginal communities, representing a suitable proxy indicator for assessing genealogical background.

  7. Social Skills Questionnaire for Argentinean College Students (SSQ-U) Development and Validation.

    PubMed

    Morán, Valeria E; Olaz, Fabián O; Del Prette, Zilda A P

    2015-11-27

    In this paper we present a new instrument called Social Skills Questionnaire for Argentinean College Students (SSQ-U). Based on the adapted version of the Social Skills Inventory - Del Prette (SSI-Del Prette) (Olaz, Medrano, Greco, & Del Prette, 2009), we wrote new items for the scale, and carried out psychometric analysis to assess the validity and reliability of the instrument. In the first study, we collected evidence based on test content through expert judges who evaluated the quality and the relevance of the items. In the second and third studies, we provided validity evidence based on the internal structure of the instrument using exploratory (n = 1067) and confirmatory (n = 661) factor analysis. Results suggested a five-factor structure consistent with the dimensions of social skills, as proposed by Kelly (2002). The fit indexes corresponding to the obtained model were adequate, and composite reliability coefficients of each factor were excellent (above .75). Finally, in the fourth study, we provided evidence of convergent and discriminant validity. The obtained results allow us to conclude that the SSQ-U is the first valid and reliable instrument for measuring social skills in Argentinean college students.

  8. Alternaria toxins in wheat during the 2004 to 2005 Argentinean harvest.

    PubMed

    Azcarate, M P; Patriarca, A; Terminiello, L; Fernández Pinto, V

    2008-06-01

    The natural occurrence of Alternaria mycotoxins in Argentinean wheat from the zone 5 South during the 2004 to 2005 harvest was investigated in 64 wheat samples. All samples were highly contaminated with a wide range of fungal species. Alternaria was found as the main component of the mycota, with an infection percentage of 100%. Three mycotoxins produced by species of Alternaria were determined in wheat: alternariol, alternariol monomethyl ether, and tenuazonic acid. Alternariol was detected in 4 (6%) of 64 samples, with a range of 645 to 1,388 microg/kg (mean of 1,054 microg/kg); alternariol monomethyl ether, with a range of 566 to 7,451 microg/kg (mean of 2,118 microg/kg) in 15 (23%) of 64 samples; and tenuazonic acid in 12 (19%) of 64 samples, with a range of 1,001 to 8,814 microg/kg (mean, 2,313 microg/kg). Alternariol monomethyl ether was the predominant toxin, but tenuazonic acid was detected in higher concentrations. Alternariol was present in fewer samples and in lower levels than were the other toxins. Tenuazonic acid and alternariol monomethyl ether occurred together in four samples, while tenuazonic acid and alternariol co-occurred in one sample. This the first report of the natural occurrence of Alternaria mycotoxins in Argentinean wheat. Toxin levels were high, probably due to the heavy infection with Alternaria species found in the samples.

  9. Fingerprint ridge density in the Argentinean population and its application to sex inference: A comparative study.

    PubMed

    Rivaldería, Noemí; Sánchez-Andrés, Ángeles; Alonso-Rodríguez, Concepción; Dipierri, José E; Gutiérrez-Redomero, Esperanza

    2016-02-01

    Fingerprint ridge density (RD) is known to vary according to sex and population, and such variation can be used for forensic purposes. The aim of this study was to analyze the fingerprint RD of two samples of the Argentinean population in order to assess their topological, digital, bilateral, sexual, and population differences for subsequent application in the inference of sex. Data were collected from the fingerprints of 172 individuals from the Buenos Aires province and 163 from the Chubut province. RD was assessed for three different count areas for all 10 fingers of each individual. In both sexes and both samples, significant differences among areas were obtained, so that radial-RD>ulnar-RD>proximal-RD. Females presented greater RD than males in all areas and on all fingers. Regarding population differences, no significant differences were found between the Buenos Aires and Chubut samples (except for proximal RD in males). However, both samples showed RD significantly different from that of the Jujuy province. The application of Bayes' theorem allowed for the identification of an RD threshold for discrimination of sexes in these Argentinean samples. In conclusion females consistently exhibit narrower epidermal ridges than males, which may evidence a universal pattern of sexual dimorphism in this trait that can be useful in forensics in the identification of individuals.

  10. An Assessment of a Social-Cognitive Model of Academic Performance in Mathematics in Argentinean Middle School Students

    ERIC Educational Resources Information Center

    Cupani, Marcos; de Minzi, Maria Cristina Richaud; Perez, Edgardo Raul; Pautassi, Ricardo Marcos

    2010-01-01

    This study tested a set of hypotheses derived from the model of academic achievement in mathematics of the Social Cognitive Career Theory in a sample of Argentinean middle school students. To this aim, 277 students (male and female; age: 13-15 years) were assessed using the following instruments: logical-mathematical self-efficacy scale,…

  11. Automated flow-based anion-exchange method for high-throughput isolation and real-time monitoring of RuBisCO in plant extracts.

    PubMed

    Suárez, Ruth; Miró, Manuel; Cerdà, Víctor; Perdomo, Juan Alejandro; Galmés, Jeroni

    2011-06-15

    In this work, a miniaturized, completely enclosed multisyringe-flow system is proposed for high-throughput purification of RuBisCO from Triticum aestivum extracts. The automated method capitalizes on the uptake of the target protein at 4°C onto Q-Sepharose Fast Flow strong anion-exchanger packed in a cylindrical microcolumn (105 × 4 mm) followed by a stepwise ionic-strength gradient elution (0-0.8 mol/L NaCl) to eliminate concomitant extract components and retrieve highly purified RuBisCO. The manifold is furnished downstream with a flow-through diode-array UV/vis spectrophotometer for real-time monitoring of the column effluent at the protein-specific wavelength of 280 nm to detect the elution of RuBisCO. Quantitation of RuBisCO and total soluble proteins in the eluate fractions were undertaken using polyacrylamide gel electrophoresis (PAGE) and the spectrophotometric Bradford assay, respectively. A comprehensive investigation of the effect of distinct concentration gradients on the isolation of RuBisCO and experimental conditions (namely, type of resin, column dimensions and mobile-phase flow rate) upon column capacity and analyte breakthrough was effected. The assembled set-up was aimed to critically ascertain the efficiency of preliminary batchwise pre-treatments of crude plant extracts (viz., polyethylenglycol (PEG) precipitation, ammonium sulphate precipitation and sucrose gradient centrifugation) in terms of RuBisCO purification and absolute recovery prior to automated anion-exchange column separation. Under the optimum physical and chemical conditions, the flow-through column system is able to admit crude plant extracts and gives rise to RuBisCO purification yields better than 75%, which might be increased up to 96 ± 9% with a prior PEG fractionation followed by sucrose gradient step.

  12. Development of a High-Speed Real-Time Polymerase Chain Reaction System Using a Circulating Water-Based Rapid Heat-Exchange

    NASA Astrophysics Data System (ADS)

    Hideyuki Terazono,; Hiroyuki Takei,; Akihiro Hattori,; Kenji Yasuda,

    2010-06-01

    Polymerase chain reaction (PCR) is a powerful technique to detect microorganisms, viruses, or cells by amplifying a single copy or a few copies of a fragment of a particular DNA sequence. To reduce acquisition time, it is necessary to decrease the temperature transition time between denaturation and extension. We have developed a simple rapid real-time microlitter-sample droplet PCR system accomplished by the rapid liquid-based heat-exchange of sample droplets by quick switching of two circulating hot waters of denaturation and extension, a microlitter-sized droplet and a thin-film aluminum chip. Using this system, rapid PCR amplification of a set of droplets lined up on an aluminum chip was conducted successfully as shown by the increase in fluorescence intensity, and was accomplished within 3.5 min in 40 cycles of 1 s denaturation and 3 s extension reaction, which is one magnitude faster than conventional fast PCR systems. This method allows the rapid detection of DNA fragments and has a possibility for measuring multiple samples simultaneously in a miniaturized microfluidic chip.

  13. Argentinean Society of Experimental Pharmacology: Brief history and main scientific contributions to the discipline.

    PubMed

    Sánchez Bruni, Sergio F; Acosta, Gabriela B

    2016-07-01

    Argentina Biomedical Science has been historically strong. The development of Human and Veterinary Pharmacology in our country as a pivotal discipline has been acknowledged worldwide because of the quality of its contributions. Argentinean Society of Experimental Pharmacology (SAFE) is a non- profit association whose research fields include Experimental and Clinical Pharmacology. SAFE main goals are described as follow (a) To meet active researchers for studying concerns regarding Experimental and Clinical Pharmacology (b) To launch an initiative for development of the discipline in mainly our country and other collaborative countries worldwide (c) To spread the pharmacological know-how obtained from different research teams (d) To strengthen relations between pharmacologists (e) To facilitate the presentation and discussion of scientific papers. This current article shows the SAFE's more important scientific contribution to pharmacology through its former research scientists to the present.

  14. In Vitro Evaluation of Antiprotozoal and Antiviral Activities of Extracts from Argentinean Mikania Species

    PubMed Central

    Laurella, Laura C.; Frank, Fernanda M.; Sarquiz, Andrea; Alonso, María R.; Giberti, Gustavo; Cavallaro, Lucia; Catalán, Cesar A.; Cazorla, Silvia I.; Malchiodi, Emilio; Martino, Virginia S.; Sülsen, Valeria P.

    2012-01-01

    The aim of this study was to investigate the antiprotozoal and antiviral activities of four Argentinean Mikania species. The organic and aqueous extracts of Mikania micrantha, M. parodii, M. periplocifolia, and M. cordifolia were tested on Trypanosoma cruzi epimastigotes, Leishmania braziliensis promastigotes, and dengue virus type 2. The organic extract of M. micrantha was the most active against T. cruzi and L. braziliensis exhibiting a growth inhibition of 77.6 ± 4.5% and 84.9 ± 6.1%, respectively, at a concentration of 10 μg/ml. The bioguided fractionation of M. micrantha organic extract led to the identification of two active fractions. The chromatographic profile and infrared analysis of these fractions revealed the presence of sesquiterpene lactones. None of the tested extracts were active against dengue virus type 2. PMID:22919289

  15. Genetic variability, phylogenetic relationships and gene flow in Triatoma infestans dark morphs from the Argentinean Chaco.

    PubMed

    Piccinali, R V; Marcet, P L; Ceballos, L A; Kitron, U; Gürtler, R E; Dotson, E M

    2011-07-01

    The recent discovery of sylvatic populations of Triatoma infestans outside the Andean Valleys of Bolivia prompted an evolutionary question about the putative ancestral area of origin and dispersal of the species, and an epidemiological question regarding the possible role of these sylvatic populations in the recolonization process of insecticide-treated houses. The finding of a population of sylvatic melanic T. infestans (dark morphs) in the Argentinean dry Chaco at 7 km from a peridomestic bug population of typical coloration gave us the opportunity to test both questions simultaneously by employing phylogenetic and population genetic approaches. For this purpose we analyzed sylvatic and peridomestic bugs using sequence-based mitochondrial and nuclear markers (mtCOI and ITS-1) and microsatellites. Sylvatic bugs were confirmed to be T. infestans and not hybrids, and showed high levels of genetic variability and departures from neutral expectations for mtCOI variation. New ITS-1 and mtCOI haplotypes were recorded, as well as haplotypes shared with peridomestic and/or domestic bugs from previous records. The peridomestic population was invariant for ITS-1 and mtCOI, but showed variability for microsatellites and signatures of a population bottleneck, probably due to a limited number of founders. Phylogenetic analyses were consistent with the presence of ancestral haplotypes in sylvatic bugs. According to F-statistics and assignment methods there was a significant differentiation between sylvatic and peridomestic bugs and gene flow was low and asymmetric, with more bugs moving from the peridomicile to the sylvatic environment. These results support the hypothesis of the Chaco region as the area of origin of T. infestans, and a limited role of sylvatic melanic T. infestans in peridomestic infestation in the Argentinean Chaco.

  16. Genetic variability, phylogenetic relationships and gene flow in Triatoma infestans dark morphs from the Argentinean Chaco

    PubMed Central

    Piccinali, R. V.; Marcet, P. L.; Ceballos, L. A.; Kitron, U.; Gürtler, R. E.; Dotson, E. M.

    2011-01-01

    The recent discovery of sylvatic populations of Triatoma infestans outside the Andean Valleys of Bolivia prompted an evolutionary question about the putative ancestral area of origin and dispersal of the species, and an epidemiological question regarding the possible role of these sylvatic populations in the recolonization process of insecticide-treated houses. The finding of a population of sylvatic melanic T. infestans (dark morphs) in the Argentinean dry Chaco at 7 km from a peridomestic bug population of typical coloration gave us the opportunity to test both questions simultaneously by employing phylogenetic and population genetic approaches. For this purpose we analyzed sylvatic and peridomestic bugs using sequence-based mitochondrial and nuclear markers (mtCOI and ITS-1) and microsatellites. Sylvatic bugs were confirmed to be T. infestans and not hybrids, and showed high levels of genetic variability and departures from neutral expectations for mtCOI variation. New ITS-1 and mtCOI haplotypes were recorded, as well as haplotypes shared with peridomestic and/or domestic bugs from previous records. The peridomestic population was invariant for ITS-1 and mtCOI, but showed variability for microsatellites and signatures of a population bottleneck, probably due to a limited number of founders. Phylogenetic analyses were consistent with the presence of ancestral haplotypes in sylvatic bugs. According to F-statistics and assignment methods there was a significant differentiation between sylvatic and peridomestic bugs and gene flow was low and asymmetric, with more bugs moving from the peridomicile to the sylvatic environment. These results support the hypothesis of the Chaco region as the area of origin of T. infestans, and a limited role of sylvatic melanic T. infestans in peridomestic infestation in the Argentinean Chaco. PMID:21352954

  17. Physical growth in schoolchildren from Argentina: comparison with Argentinean and CDC/NCHs growth references.

    PubMed

    Orden, Alicia B; Torres, María F; Castro, Luis; Cesani, María F; Luis, María A; Quintero, Fabián A; Oyhenart, Evelia E

    2009-01-01

    The aim of this study was to assess the physical growth of schoolchildren from Argentina by comparison with the CDC/NCHS and Argentinean growth references (AGR), to contribute to the discussion about the use of local or international references for the assessment of growth in developing countries. Weight and height were measured in 3,411 schoolchildren aged 5-14 years. Data were log-transformed and compared with both references by paired samples t-test (CI = 0.95; alpha = 0.005). The boys' weights were greater than CDC/NCHS (up to 10, and at 14 years old) and the national reference at all ages (P < 0.005). The girls also were heavier than CDC/NCHS (at 7 and 12 years old, P < 0.005) and AGR, except at age 11 and 14 years. In boys, height was lower than CDC/NCHS at 9 and 14 years of age, and higher than AGR at all ages (P < 0.005). The girls were also shorter than CDC/NCHS at 7, 13, and 14 years old (P < 0.005), and-except at age 14-taller than AGR. The weight was higher than both of the references. Height showed a clear dissociation from the national reference and minor differences from CDC/NCHS. Nevertheless, around puberty, the children's height fell short of CDC/NCHS, especially the girls, whose values approached those of their Argentinean peers. This divergence could be associated with cohort effects or population variations in adolescent growth spurt. The use of a single growth reference for preadolescent may be appropriate. The height decrease in adolescents suggests the usefulness of local standards at this period.

  18. Tobacco advertising and press coverage of smoking and health in 10 years of Argentinean newspapers

    PubMed Central

    Braun, Sandra; Mejia, Raul; Barnoya, Joaquín; Gregorich, Steven E.; Pérez-Stable, Eliseo J.

    2013-01-01

    Objective To describe the extent and content of tobacco-related images, advertising and articles published in the largest Argentinean newspapers before and after a voluntary advertising ban implemented in 2001. Methods Issues from four months of each year of the four main national newspapers were examined from 1995 to 2004. We recorded the number of tobacco images (advertisement or not), tobacco-focused articles, space used, and placement within the newspaper. Regression analyses evaluated time trends. Results We identified 1800 images and articles from 4828 different issues. Non-advertisement images were the most frequent (71.2%), followed by articles (20%) and advertisement images (8.8%). Advertisements only appeared in the two best selling newspapers with a majority (57%) in the Sunday magazine and 21% in the sports sections. Non-advertisement images were published in the sports and entertainment sections (55%) and showed a public figure in 88%. Of 336 articles, 39% focused on health topics and 55% emphasized the negative effects of tobacco on health. Regression models showed that prior to 2001 there were significant time-related decreases in ad images and articles and significant increases in non-ad images. The trend of each outcome changed direction beginning in 2001 and the magnitude of the change in trend was significant for ad images and non-ad images. The number of non-ad images dropped significantly in 2001 from a model-predicted value of 178 per year to 103 non-ad images and remained constant thereafter. Conclusions Tobacco images exceeded information about tobacco hazards in Argentinean newspapers over this period. Advertisement increased from 2001 to 2005, following the voluntary advertisements ban. Partial advertisement bans are ineffective and a total ban is imperative. PMID:24032052

  19. Morphological, morphometric, meristic and osteological evidence for two species of hake (Actinopterygii: Gadiformes: Merluccius) in Argentinean waters.

    PubMed

    Díaz de Astarloa, J M; Bezzi, S I; González Castro, M; Mabragaña, E; Hernández, D; Delpiani, S M; Figueroa, D E; Cousseau, M B; Deli Antoni, M Y; Tringali, L

    2011-05-01

    Morphologically, both classic and landmark-based morphometry and meristic analyses of 241 specimens of Merluccius, along with the re-examination of six paratype specimens of Merluccius hubbsi, the holotype and three paratypes of Merluccius patagonicus and the syntype of Merluccius australis revealed the presence of only two species of Merluccius in Argentinean waters. Internal structures (hyomandibula, urohyal and sagitta otolith) of M. hubbsi were compared to those reported for M. patagonicus and were shown to have identical morphology. Type specimens of M. patagonicus showed a complete overlap in morphometric and meristic characters with M. hubbsi, whereas M. australis had a greater number of second dorsal and anal-fin rays, and more lateral-line scales. In addition, M. australis had a smaller eye and longer snout than M. hubbsi and M. patagonicus. The results indicate that there is no evidence for a third hake species in Argentinean waters. Merluccius patagonicus is a synonym of M. hubbsi.

  20. Paralytic poliomyelitis caused by a vaccine-derived polio virus in an antibody-deficient Argentinean child.

    PubMed

    Hidalgo, Solange; García Erro, Marcela; Cisterna, Daniel; Freire, M Cecilia

    2003-06-01

    We describe a case of poliomyelitis in a 3-year-old Argentinean boy with X-linked hypogammaglobulinemia. The child had no history of polio vaccination, but a poliovirus isolated from a stool sample had 97.2% genetic similarity to the Sabin 1 vaccine strain. According to the WHO definition, this is the first case reported of a vaccine-derived poliovirus infection recorded in continental Latin America.

  1. PSYCHOMETRIC PROPERTIES OF THE THREE PATHWAYS TO WELL-BEING SCALE IN A LARGE SAMPLE OF ARGENTINEAN ADOLESCENTS.

    PubMed

    Góngora, Vanesa C; Castro Solano, Alejandro

    2015-08-01

    The Authentic Happiness Theory considers that well-being can be reached by three main pathways: a pleasant life, an engaged life, or a meaningful life. This study investigates the psychometric properties of the Three Pathways to Well-being scale in Argentinean adolescents and compares that to prior results for Argentinean adults. A sample of 255 Argentinean adolescent students (110 boys, 145 girls) aged between 13 and 18 years (M age = 15.5, SD = 1.6) was used in this study. The participants completed the Spanish versions of the Three Pathways to Well-being scale, the Meaning in Life Questionnaire, the Satisfaction With Life Scale, and the Personal Wellbeing Index. Confirmatory factor analyses verified the three-factor structure of the test, accounting for 46% of the variance. The internal consistencies were α = .76 for the pleasant life, α = .80 for the engaged life, and α = .70 for the meaningful life. Concurrent validity was examined with the Satisfaction With Life Scale, the Personal Wellbeing Index, and the Meaning in Life Questionnaire, and the engaged life was the pathway most strongly associated with the positive related measures.

  2. 8th Argentinean Bioengineering Society Conference (SABI 2011) and 7th Clinical Engineering Meeting

    NASA Astrophysics Data System (ADS)

    Meschino, Gustavo Javier; Ballarin, Virginia L.

    2011-12-01

    In September 2011, the Eighteenth Edition of the Argentinean Bioengineering Society Conference (SABI 2011) and Seventh Clinical Engineering Meeting were held in Mar del Plata, Argetina. The Mar del Plata SABI Regional and the School of Engineering of the Universidad Nacional de Mar del Plata invited All bioengineers, engineers, physicists, mathematicians, biologists, physicians and health professionals working in the field of Bioengineering to participate in this event. The overall objectives of the Conference were: To provide discussion of scientific research results in Bioengineering and Clinical Engineering. To promote technological development experiences. To strengthen the institutional and scientific communication links in the area of Bioengineering, mainly between Universities of Latin America. To encourage students, teachers, researchers and professionals to establish exchanges of experiences and knowledge. To provide biomedical engineering technology solutions to the society and contributing ideas for low cost care. Conference photograph Conference photograph Conference photograph Conference photograph EXECUTIVE COMMITTEE SABI 2011 Chair Dra Virginia L Ballarin Universidad Nacional de Mar del Plata Co-Chair Dra Teresita R Cuadrado Universidad Nacional de Mar del Plata - CONICET Local Comittee Dr Gustavo Abraham Universidad Nacional de Mar del Plata - CONICET Dra Josefina Ballarre Universidad Nacional de Mar del Plata - CONICET Dr Eduardo Blotta Universidad Nacional de Mar del Plata Dra Agustina Bouchet Universidad Nacional de Mar del Plata Dr Marcel Brun Universidad Nacional de Mar del Plata Dra Silvia Ceré Universidad Nacional de Mar del Plata - CONICET Dra Mariela Azul Gonzalez Universidad Nacional de Mar del Plata - CONICET Dra Lucia Isabel Passoni Universidad Nacional de Mar del Plata Dr Juan Ignacio Pastore Universidad Nacional de Mar del Plata - CONICET Dra Adriana Scandurra Universidad Nacional de Mar del Plata SCIENTIFIC ADVISORY COMMITTEE

  3. Characterization of Alternaria strains from Argentinean blueberry, tomato, walnut and wheat.

    PubMed

    Andersen, Birgitte; Nielsen, Kristian F; Fernández Pinto, Virginia; Patriarca, Andrea

    2015-03-02

    Alternaria species have the ability to produce a variety of secondary metabolite, which plays important roles in food safety. Argentina is the second largest exporter of fresh and processed food products to Europe, however, few studies on Alternaria mycotoxins and other bioactive secondary metabolites have been carried out on Argentinean cereals, fruit and vegetables. Knowing the full chemical potential and the distribution of Alternaria spp. on crops, it is necessary to establish a toxicological risk assessment for food products for human consumption. In the present study, 87 Alternaria strains from different substrates (tomato, wheat, blueberries and walnuts) were characterized according to morphology and metabolite production. Aggressive dereplication (accurate mass, isotopic patterns and lists of all described compounds from Alternaria) was used for high-throughput evaluation of the chemical potential. Four strains belonged to the Alternaria infectoria sp.-grp., 6 to the Alternaria arborescens sp.-grp., 6 showed a sporulation pattern similar to that of "M" according to Simmons, 1 to that of Alternaria vaccinii, and the remaining 70 constituted a diverse group belonging to morphological groups "G" and "H". The cluster analysis yielded 16 almost identical dendrograms and grouped the Alternaria strains into four clusters and 11 singletons and outlier groups. The chemical analysis showed that AOH and AME were the most common metabolites produced, followed by TEN, ALXs and TeA. The A. infectoria sp.-grp. had no metabolites in common with the rest of the strains. Several secondary metabolites isolated from large-spored Alternaria species or other fungal genera were detected, such as dehydrocurvularin, pyrenochaetic acid and alternarienonic acid. The strains isolated from tomato produced lower amounts of metabolites than strains from blueberries, walnut and wheat, although individual strains from tomato produced the highest amount of some metabolites. The A

  4. A cross-sectional model of eating disorders in Argentinean overweight and obese children.

    PubMed

    Elizathe, Luciana Soledad; Arana, Fernán Guido; Rutsztein, Guillermina

    2016-09-27

    Despite the fact that past research identified childhood obesity as an antecedent of eating disorders, not all obese children further develop this pathology. With this regard, our first purpose was to isolate which characteristics differentiate overweight children who have an eating disorder from those who have not. Second, considering that there is little evidence collected in Latin American countries, we provided overweight children data from an Argentinean sample. Specifically, we investigated if weight-teasing, perfectionism, disturbed eating attitudes and behaviors, and body image dissatisfaction are related to the occurrence of an eating disorder in 100 school-aged overweight/obese children (37 girls and 63 boys; mean age 10.85, SD 0.88). Participants completed self-report instruments and were interviewed between 1 and 2 months later to confirm the presence of eating disorders. Seventeen percent participants confirmed to have an eating disorder. Further, the multivariate logistic analysis revealed that perfectionism (Exp β = 1.19) and disturbed eating attitudes and behaviors (Exp β = 4.78) were jointly associated with the presence of an eating disorder. These results were maintained even when the overall model was adjusted for covariates such as age, gender, body mass index, and school type. Weight-teasing and body image dissatisfaction did not contribute to the multivariate model. Prevalence rates of ED and model findings were discussed.

  5. Perceived parenting and social support: can they predict academic achievement in Argentinean college students?

    PubMed Central

    de la Iglesia, Guadalupe; Freiberg Hoffmann, Agustin; Fernández Liporace, Mercedes

    2014-01-01

    The aim of this study was to test the ability to predict academic achievement through the perception of parenting and social support in a sample of 354 Argentinean college students. Their mean age was 23.50 years (standard deviation =2.62 years) and most of them (83.3%) were females. As a prerequisite for admission to college, students are required to pass a series of mandatory core classes and are expected to complete them in two semesters. Delay in completing the curriculum is considered low academic achievement. Parenting was assessed taking into account the mother and the father and considering two dimensions: responsiveness and demandingness. Perceived social support was analyzed considering four sources: parents, teachers, classmates, and best friend or boyfriend/girlfriend. Path analysis showed that, as hypothesized, responsiveness had a positive indirect effect on the perception of social support and enhanced achievement. Demandingness had a different effect in the case of the mother as compared to the father. In the mother model, demandingness had a positive direct effect on achievement. In the case of the father, however, the effect of demandingness had a negative and indirect impact on the perception of social support. Teachers were the only source of perceived social support that significantly predicted achievement. The pathway that belongs to teachers as a source of support was positive and direct. Implications for possible interventions are discussed. PMID:25258563

  6. Argentinean adaptation of the Social Skills Inventory IHS-Del-Prette.

    PubMed

    Olaz, Fabián Orlando; Medrano, Leonardo; Greco, María Eugenia; Del Prette, Zilda Aparecida Pereira

    2009-11-01

    We present the results of the adaptation of the IHS-Del-Prette (Inventario de Habilidades Sociales, in English, Social Skills Inventory) to a sample of Argentinean college students. Firstly, we addressed the backward translation and carried out an equivalence study of the Portuguese and Spanish versions of the scale. The results showed the two versions were equivalent, as we obtained correlations lower than .50 in only 5 items. Secondly, we performed item analysis by calculating discrimination indexes and item-total correlations. Results indicated that the items are sensitive to differentiate between high and low social-skill groups. Exploratory factor analysis carried out with a sample of 602 college students yielded five factors that explained 26.5% of the total variance, although our data did not completely match the original factor structure. We also obtained moderate alpha values for the subscales, but high reliability for the total scale. Lastly, group differences between males and females are presented to provide evidence of validity. We discuss the implications of the results and present future lines of inquiry.

  7. Perceived parenting and social support: can they predict academic achievement in Argentinean college students?

    PubMed

    de la Iglesia, Guadalupe; Freiberg Hoffmann, Agustin; Fernández Liporace, Mercedes

    2014-01-01

    The aim of this study was to test the ability to predict academic achievement through the perception of parenting and social support in a sample of 354 Argentinean college students. Their mean age was 23.50 years (standard deviation =2.62 years) and most of them (83.3%) were females. As a prerequisite for admission to college, students are required to pass a series of mandatory core classes and are expected to complete them in two semesters. Delay in completing the curriculum is considered low academic achievement. Parenting was assessed taking into account the mother and the father and considering two dimensions: responsiveness and demandingness. Perceived social support was analyzed considering four sources: parents, teachers, classmates, and best friend or boyfriend/girlfriend. Path analysis showed that, as hypothesized, responsiveness had a positive indirect effect on the perception of social support and enhanced achievement. Demandingness had a different effect in the case of the mother as compared to the father. In the mother model, demandingness had a positive direct effect on achievement. In the case of the father, however, the effect of demandingness had a negative and indirect impact on the perception of social support. Teachers were the only source of perceived social support that significantly predicted achievement. The pathway that belongs to teachers as a source of support was positive and direct. Implications for possible interventions are discussed.

  8. Influence of oregano essential oil on traditional Argentinean cheese elaboration: Effect on lactic starter cultures.

    PubMed

    Marcial, Guillermo E; Gerez, Carla L; de Kairuz, Martha Nuñez; Araoz, Victoria Coll; Schuff, Carola; de Valdez, Graciela Font

    The aim of this work is to study the oregano essential oil (OEO) composition from Northwestern Argentinean regions and to evaluate its effect on the lactic starter cultures. The oregano used, Origanum vulgare var hirtum, was obtained from Andalgalá, Catamarca. The essential oil presented high amounts of α-terpinene (10%), γ-terpinene (15.1%), terpinen-4-ol (15.5%) and thymol (13.0%) as the main components. No negative effect on growth or metabolic activity of lactic acid bacteria Streptococcus thermophilus CRL 728 and CRL 813, Lactobacillus delbrueckii subsp. bulgaricus CRL 656 and CRL 468, and Lactococcus lactis subsp. lactis CRL 597 up to the maximum concentration (200μg/g) assayed was observed. No differences in the organoleptic characteristics of semi-hard cheeses flavored with oregano essential oil (200μg/g) and homemade cheeses flavored with oregano leaves were found. With respect to the microbiological quality of the products, neither enterobacteria nor mold and yeast were detected during ripening in essential-oil flavored cheese compared to control cheese (enterobacteria 2×10(3)UFC/g) and cheese flavored with oregano leaves (mold/yeast 4×10(4)CFU/g). Our results showed that the use of oregano essential oil and lactic starter culture considerably improved cheese quality.

  9. Identification of botanical biomarkers in Argentinean Diplotaxis honeys: flavonoids and glucosinolates.

    PubMed

    Truchado, Pilar; Tourn, Elian; Gallez, Lilliana M; Moreno, Diego A; Ferreres, Federico; Tomás-Barberán, Francisco A

    2010-12-22

    To select and establish floral biomarkers of the botanical origin of Diplotaxis tenuifolia honeys, the flavonoids and glucosinolates present in bee-deposited nectar collected from hive combs (unripe honey) and mature honey from the same hives fron which the unripe honey samples were collected were analyzed by LC-UV-PAD-ESI-MS(n). Glycosidic conjugates of the flavonols quercetin, kaempferol, and isorhamnetin were detected and characterized in unripe honey. D. tenuifolia mature honeys contained the aglycones kaempferol, quercetin, and isorhamnetin. The differences between the phenolic profiles of mature honey and freshly deposited honey could be due to hydrolytic enzymatic activities. Aliphatic and indole glucososinolates were analyzed in unripe and mature honeys, this being the first report of the detection and characterization of glucosinolates as honey constituents. Moreover, these honey samples contained different amounts of propolis-derived flavonoid aglycones (1765-3171 μg/100 g) and hydroxycinnamic acid derivatives (29-1514 μg/100 g). Propolis flavonoids were already present in the freshly deposited nectar, showing that the incorporation of these compounds to honey occurs at the early steps of honey production. The flavonoids quercetin, kaempferol, and isorhamnetin and the glucosinolates detected in the samples could be used as complementary biomarkers for the determination of the floral origin of Argentinean Diplotaxis honeys.

  10. [Development and psychometric assessment of the Alcohol Expectancy Questionnaire for Argentinean Children (CEA-N)].

    PubMed

    Pilatti, Angelina; Godoy, Juan Carlos; Alejandra Brussino, Silvina

    2010-01-01

    A new measure of positive and negative alcohol expectancies for children aged 8 to 12 years was developed and validated. Study 1: 117 children answered a structured open-format question to provide information regarding the effects of alcohol use that they anticipate. The pool of items obtained was analyzed by a group of three experts according to the following criteria: item correspondence with two different theoretical models and item semantic clarity. Following analysis of the agreement between judges, a set of 55 items was obtained. Study 2: 209 children answered the Alcohol Expectancy Questionnaire for Children (CEA-N). Internal structure was analyzed through the use of exploratory factor analysis. A principal components analysis with oblimin rotation yielded a five-factor structure. The measure was found to demonstrate good internal consistency for the global and 'risk and aggression' scales, and moderate internal consistency for the remaining four scales: sociability, relaxation, courage and negative mood. These results indicate that the CEA-N is a valid and reliable measure for assessing alcohol expectancies in Argentinean children.

  11. Charting the Y-chromosome ancestry of present-day Argentinean Mennonites.

    PubMed

    Toscanini, Ulises; Brisighelli, Francesca; Llull, Cintia; Berardi, Gabriela; Gómez, Andrea; Andreatta, Fernando; Pardo-Seco, Jacobo; Gómez-Carballa, Alberto; Martinón-Torres, Federico; Álvarez-Iglesias, Vanesa; Salas, Antonio

    2016-06-01

    Old Order Mennonite communities initially arose in Northern Europe (centered in the Netherlands) and derived from the Anabaptist movement of the 16th century. Mennonites migrated to the New World in the early 18th century, first to North America, and more recently to Mesoamerica and South America. We analyzed Y-chromosome short tandem repeats (STRs) and single nucleotide polymorphisms in males from a community of Mennonites, 'La Nueva Esperanza', which arrived to Argentina in 1985 from colonies in Bolivia and Mexico. Molecular diversity indices coupled with demographic simulations show that Mennonites have a reduced variability when compared with local Argentinean populations and 69 European population samples. Mennonite Y-STR haplotypes were mainly observed in Central Europe. In agreement, multidimensional scaling analyses based on RST genetic distances indicate that Mennonite Y-chromosomes are closely related to Central/Northern Europeans (the Netherlands, Switzerland and Denmark). In addition, statistical inferences made on the most likely geographic origin of Y-chromosome haplotypes point more specifically to the Netherlands as the populations that best represent the majority of the Mennonite Y-chromosomes. Overall, Y-chromosome variation of Mennonites shows the signatures of moderate reduction of variability when compared with source populations, which is in good agreement with their lifestyle in small endogamous demes. These genetic singularities could also help to understand disease conditions that are more prevalent among Mennonites.

  12. Pyrolysis of sugarcane bagasse and co-pyrolysis with an Argentinean subbituminous coal

    SciTech Connect

    Bonelli, P.R.; Buonomo, E.L.; Cukierman, A.L.

    2007-07-01

    Physicochemical properties of the charcoal arising from pyrolysis of sugarcane bagasse at 600{sup o}C and 800{sup o}C were determined to evaluate potentialities for specific end uses. The charcoals were found fairly adequate as solid bio-fuels. Their quality was comparable to charcoals obtained from some other agro-industrial by-products, reportedly proposed as substitutes of wood-based ones. Surface properties of the charcoal generated at the higher temperature indicated that it is reasonably suited for potential use as low-cost rough adsorbent, soil amender, and/or for further upgrading to activated carbon. Moreover, kinetic measurements for pyrolysis of the sugarcane bagasse individually and mixed with an Argentinean subbituminous coal in equal proportions were conducted by thermogravimetry for the range 25 -900{sup o}C. Data modeling accounting for variations in the activation energy with process evolution provided a proper description of pyrolysis and co-pyrolysis over the entire temperature range.

  13. Description and molecular diagnosis of a new species of Brunfelsia (Solanaceae) from the Bolivian and Argentinean Andes.

    PubMed

    Filipowicz, Natalia; Nee, Michael H; Renner, Susanne S

    2012-01-01

    Brunfelsia plowmaniana N.Filipowicz & M.Nee sp. nov., a species from humid and cloud forests of the Bolivian and Argentinean Andes, is described and provided with a molecular diagnosis, using provisions available in the recently approved International Code of Nomenclature for algae, fungi and plants. Specimens belonging to the new species were previously placed in the polymorphic Brunfelsia uniflora (Pohl) D.Don, which a molecular phylogeny revealed as polyphyletic. Revision of numerous collections revealed clear morphological differences between the new species and Brunfelsia uniflora, the type locality of which is in the state of São Paulo, Brazil.

  14. Description and molecular diagnosis of a new species of Brunfelsia (Solanaceae) from the Bolivian and Argentinean Andes

    PubMed Central

    Filipowicz, Natalia; Nee, Michael H.; Renner, Susanne S.

    2012-01-01

    Abstract Brunfelsia plowmaniana N.Filipowicz & M.Nee sp. nov., a species from humid and cloud forests of the Bolivian and Argentinean Andes, is described and provided with a molecular diagnosis, using provisions available in the recently approved International Code of Nomenclature for algae, fungi and plants. Specimens belonging to the new species were previously placed in the polymorphic Brunfelsia uniflora (Pohl) D.Don, which a molecular phylogeny revealed as polyphyletic. Revision of numerous collections revealed clear morphological differences between the new species and Brunfelsia uniflora, the type locality of which is in the state of São Paulo, Brazil. PMID:22461731

  15. The role of sigmodontine rodents as sylvatic hosts of Trypanosoma cruzi in the Argentinean Chaco.

    PubMed

    Orozco, M Marcela; Piccinali, Romina V; Mora, Matías S; Enriquez, Gustavo F; Cardinal, M Victoria; Gürtler, Ricardo E

    2014-03-01

    The role of rodents in the sylvatic transmission of Trypanosoma cruzi has seldom been investigated using parasitological and molecular methods. We assessed the occurrence of T. cruzi in wild small rodents from Pampa del Indio, in the Argentinean Chaco, and identified the taxonomic status of positive rodents by sequencing a fragment of cytochrome b gene (cytb) and performing BLAST searches and phylogenetic analyses. A total of 176 Sigmodontinae rodents was captured in six surveys using 5425 trap-nights in a wide range of sylvatic habitats between 2009 and 2011. Host infection was determined by xenodiagnosis and by polymerase chain reaction amplification of the hyper-variable region of kinetoplast DNA minicircles of T. cruzi (kDNA-PCR) from blood samples. None of the 176 rodents examined was xenodiagnosis-positive. The prevalence of infection determined by kDNA-PCR from blood samples was 16.2% (95% confidence interval, 10.1-21.9%). Half of the infections detected by kDNA-PCR were confirmed by nuclear satellite DNA-PCR or by kDNA-PCR of the rectal contents of xenodiagnostic bugs. The 24 positive specimens were assigned to eight species, providing the first records of T. cruzi in Akodon montensis, Akodon toba, Graomys chacoensis, and Oligoryzomys chacoensis. The occurrence of T. cruzi infection in Oligoryzomys nigripes, Calomys callosus, Necromys lasiurus and Oecomys sp. (most probably Oecomys mamorae) from the Gran Chaco is also reported for the first time. Although sigmodontine rodents were frequently infected, the intensity of bug rectal infection with T. cruzi was below the detection limit of xenodiagnosis (subpatent infectiousness to bugs), indicating they had a low reservoir host competence.

  16. The PAMPA datasets: a metagenomic survey of microbial communities in Argentinean pampean soils

    PubMed Central

    2013-01-01

    Background Soil is among the most diverse and complex environments in the world. Soil microorganisms play an essential role in biogeochemical cycles and affect plant growth and crop production. However, our knowledge of the relationship between species-assemblies and soil ecosystem processes is still very limited. The aim of this study was to generate a comprehensive metagenomic survey to evaluate the effect of high-input agricultural practices on soil microbial communities. Results We collected soil samples from three different areas in the Argentinean Pampean region under three different types of land uses and two soil sources (bulk and rhizospheric). We extracted total DNA from all samples and also synthetized cDNA from rhizospheric samples. Using 454-FLX technology, we generated 112 16S ribosomal DNA and 14 16S ribosomal RNA amplicon libraries totaling 1.3 M reads and 36 shotgun metagenome libraries totaling 17.8 million reads (7.7 GB). Our preliminary results suggested that water availability could be the primary driver that defined microbial assemblages over land use and soil source. However, when water was not a limiting resource (annual precipitation >800 mm) land use was a primary driver. Conclusion This was the first metagenomic study of soil conducted in Argentina and our datasets are among the few large soil datasets publicly available. The detailed analysis of these data will provide a step forward in our understanding of how soil microbiomes respond to high-input agricultural systems, and they will serve as a useful comparison with other soil metagenomic studies worldwide. PMID:24450949

  17. Cytotoxic effects of Argentinean plant extracts on tumour and normal cell lines.

    PubMed

    Mamone, L; Di Venosa, G; Valla, J J; Rodriguez, L; Gándara, L; Batlle, A; Heinrich, M; Juarranz, A; Sanz-Rodriguez, F; Casas, A

    2011-05-30

    In the search for possible new anti-cancer agents, we investigated the effects of 75 aqueous and methanol extracts from 41 Argentinean plant species. The effect in cell growth was evaluated in the LM2 mammary adenocarcinoma cells. In a second stage, the highly active selected extracts were assayed in 3 other tumour cell lines: melanoma B16, bladder MB49 and lung A549; and 3 normal cell lines: mammary Hb4a and keratinocytes PAM212 and HaCat. Eight methanol extracts were found to be highly cytotoxic: Collaea argentina leaf, Iochroma australe leaf, Ipomoea bonariensis flower, Jacaranda mimosifolia flower, Solanum amygdalifolium flower, Solanum chacoense leaf, Solanum sisymbriifolium flower and Solanum verbascifolium flower. However, extract inhibition on cell growth was highly dependent on cell type. In general, except for the highly resistant cell lines, the inhibitory concentrations 50% were in the range of 10-150 μg/ml The eight extracts highly inhibited cell growth in a concentration-dependent manner, and in general the methanol extracts were always more active than the aqueous. Murine cells appear to be more sensitive than human cells to the cytotoxic action of the plant extracts. The human melanoma B16 line was the most resistant to four of the extracts. In terms of selectivity, S. verbascifolium was the species which showed most selectivity for tumour cells. Overall, this is one of the first studies focusing on southern South American native plants and their biological effects. Since some species of 5 genera analyzed have been reported to possess different degrees of alkaloid content, we examined microtubule structures after extract treatments. The eight extracts induced destabilization, condensation and aggregation of microtubules in LM2 cells, although no depolarization, typical of Vinca alkaloids damage was observed. In a near future, antitumour activity of purified fractions of the extracts administered at non-toxic doses will be assayed in transplantable

  18. Biogeographical Boundaries, Functional Group Structure and Diversity of Rocky Shore Communities along the Argentinean Coast

    PubMed Central

    Wieters, Evie A.; McQuaid, Christopher; Palomo, Gabriela; Pappalardo, Paula; Navarrete, Sergio A.

    2012-01-01

    We investigate the extent to which functional structure and spatial variability of intertidal communities coincide with major biogeographical boundaries, areas where extensive compositional changes in the biota are observed over a limited geographic extension. We then investigate whether spatial variation in the biomass of functional groups, over geographic (10′s km) and local (10′s m) scales, could be associated to species diversity within and among these groups. Functional community structure expressed as abundance (density, cover and biomass) and composition of major functional groups was quantified through field surveys at 20 rocky intertidal shores spanning six degrees of latitude along the southwest Atlantic coast of Argentina and extending across the boundaries between the Argentinean and Magellanic Provinces. Patterns of abundance of individual functional groups were not uniformly matched with biogeographical regions. Only ephemeral algae showed an abrupt geographical discontinuity coincident with changes in biogeographic boundaries, and this was limited to the mid intertidal zone. We identified 3–4 main ‘groups’ of sites in terms of the total and relative abundance of the major functional groups, but these did not coincide with biogeographical boundaries, nor did they follow latitudinal arrangement. Thus, processes that determine the functional structure of these intertidal communities are insensitive to biogeographical boundaries. Over both geographical and local spatial scales, and for most functional groups and tidal levels, increases in species richness within the functional group was significantly associated to increased total biomass and reduced spatial variability of the group. These results suggest that species belonging to the same functional group are sufficiently uncorrelated over space (i.e. metres and site-to-site ) to stabilize patterns of biomass variability and, in this manner, provide a buffer, or “insurance”, against spatial

  19. mtDNA diversity in Azara's owl monkeys (Aotus azarai azarai) of the Argentinean Chaco.

    PubMed

    Babb, Paul L; Fernandez-Duque, Eduardo; Baiduc, Caitlin A; Gagneux, Pascal; Evans, Sian; Schurr, Theodore G

    2011-10-01

    Owl monkeys (Aotus spp.) inhabit much of South America yet represent an enigmatic evolutionary branch among primates. While morphological, cytogenetic, and immunological evidence suggest that owl monkey populations have undergone isolation and diversification since their emergence in the New World, problems with adjacent species ranges, and sample provenance have complicated efforts to characterize genetic variation within the genus. As a result, the phylogeographic history of owl monkey species and subspecies remains unclear, and the extent of genetic diversity at the population level is unknown. To explore these issues, we analyzed mitochondrial DNA (mt DNA) variation in a population of wild Azara's owl monkeys (Aotus azarai azarai) living in the Gran Chaco region of Argentina. We sequenced the complete mitochondrial genome from one individual (16,585 base pairs (bp)) and analyzed 1,099 bp of the hypervariable control region (CR) and 696 bp of the cytochrome oxidase II (COII) gene in 117 others. In addition, we sequenced the mitochondrial genome (16,472 bp) of one Nancy Ma's owl monkey (A. nancymaae). Based on the whole mtDNA and COII data, we observed an ancient phylogeographic discontinuity among Aotus species living north, south, and west of the Amazon River that began more than eight million years ago. Our population analyses identified three major CR lineages and detected a high level of haplotypic diversity within A. a. azarai. These data point to a recent expansion of Azara's owl monkeys into the Argentinean Chaco. Overall, we provide a detailed view of owl monkey mtDNA variation at genus, species, and population levels.

  20. Nonstarter lactobacilli isolated from soft and semihard Argentinean cheeses: genetic characterization and resistance to biological barriers.

    PubMed

    Ugarte, Mariana Bude; Guglielmotti, Daniela; Giraffa, Giorgio; Reinheimer, Jorge; Hynes, Erica

    2006-12-01

    Nonstarter lactic acid bacteria isolated from Argentinean cheeses were identified and characterized by focusing on their resistance to biological barriers, along with other physiological features of potential interest, in the search for future probiotic organisms. Lactobacilli were enumerated and isolated from semihard and soft cheeses made with multistrain Streptococcus thermophilus starters. Lactobacilli counts in 1-week-old cheeses were between 10(5) and 10(7) CFU/g and then reached 10(7) CFU/ g in all 1-month samples, while streptococci were always above 10(9) CFU/g. A total number of 22 lactobacilli isolates were retained, identified, and characterized by in vitro tests. Species identity was determined by carbohydrate metabolism and species-specific PCR assays. Genetic diversity was explored by random amplified polymorphic DNA (RAPD) PCR analysis. The Lactobacillus strains were assigned to the species L. casei, L. plantarum, L. rhamnosus, L. curvatus, L. fermentum, and L. perolens. All the strains studied tolerated 25 ppm of lysozyme, and most of them showed resistance to 0.3% bile. After incubation in gastric solution (pH 2.0), counts decreased by several log units, ranging from 3.2 to 7.0. The strains were able to grow in the presence of bile salts, but only three isolates were capable of deconjugation. The nonstarter lactobacilli that were assayed fermented the prebiotic substrates (especially lactulose and inulin). Some strains showed high cell hydrophobicity and beta-galactosidase activity, as well as inhibitory activity against pathogenic bacteria. It was concluded that most of the lactobacilli isolated in this study demonstrated resistance to biological barriers and physiological characteristics compatible with probiotic properties, which make them suitable for further research in in vivo studies aimed at identifying new probiotic organisms.

  1. Spatial Genetic Structure and Mitochondrial DNA Phylogeography of Argentinean Populations of the Grasshopper Dichroplus elongatus

    PubMed Central

    Rosetti, Natalia; Remis, Maria Isabel

    2012-01-01

    Many grasshopper species are considered of agronomical importance because they cause damage to pastures and crops. Comprehension of pest population dynamics requires a clear understanding of the genetic diversity and spatial structure of populations. In this study we report on patterns of genetic variation in the South American grasshopper Dichroplus elongatus which is an agricultural pest of crops and forage grasses of great economic significance in Argentina. We use Direct Amplification of Minisatellite Regions (DAMD) and partial sequences of the cytochrome oxydase 1 (COI) mitochondrial gene to investigate intraspecific structure, demographic history and gene flow patterns in twenty Argentinean populations of this species belonging to different geographic and biogeographic regions. DAMD data suggest that, although genetic drift and migration occur within and between populations, measurable relatedness among neighbouring populations declines with distance and dispersal over distances greater than 200 km is not typical, whereas effective gene flow may occur for populations separated by less than 100 km. Landscape analysis was useful to detect genetic discontinuities associated with environmental heterogeneity reflecting the changing agroecosystem. The COI results indicate the existence of strong genetic differentiation between two groups of populations located at both margins of the Paraná River which became separated during climate oscillations of the Middle Pleistocene, suggesting a significant restriction in effective dispersion mediated by females and large scale geographic differentiation. The number of migrants between populations estimated through mitochondrial and DAMD markers suggest that gene flow is low prompting a non-homogeneous spatial structure and justifying the variation through space. Moreover, the genetic analysis of both markers allows us to conclude that males appear to disperse more than females, reducing the chance of the genetic loss

  2. Real-time monitoring of the overall exchange of oxygen isotopes between aqueous CO32- and H2O by Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Geisler, Thorsten; Perdikouri, Christina; Kasioptas, Argyrios; Dietzel, Martin

    2012-08-01

    In this contribution we demonstrate that in situ Raman spectroscopy is a powerful tool to study the exchange kinetics of oxygen isotopes between aqueous oxo-anions and water using the CO32--H2O system as an example. In situ exchange experiments have been carried out using a 1 M Na2CO3 solution at 45, 60, 75, and 100 °C in a closed system using an in-house-made Teflon©-based fluid cell. The solution was prepared with H2O enriched with 97 at.% 18O. At the given pH from 10.92 to 9.65 at 45-100 °C, respectively, CO32- is the dominant DIC species (>99% CO32-). At the beginning of the reaction the Raman spectrum of the solution is characterised by an intense band near 1067 cm-1 that has been assigned to the ν1(CO3) symmetric stretching vibration of the CO32- molecule. With increasing reaction time three, well-separated bands successively appear near 1046, 1026, and 1006 cm-1. These bands result from mass-related (isotopic) splitting of the ν1(CO3) mode and reflect the symmetric stretching vibration of the oxygen-related isotopologues C16O3-n18On2- (n = 1, 2, and 3). The relative integrated intensities of these bands are related to the amount of 18O present in the aqueous CO32- molecule, which allowed monitoring the time-dependent distribution of the four isotopologues at each temperature. The measured distributions as a function of time were found to agree well with those modelled on the basis of the overall reactions ΣC18O+3H18O⇌ΣC18O16O+3H16O, where the sum sign represents the sum of all carbonate species in solution and n = 0, 1, and 2. Moreover, the measured equilibrium fractions of 18O agree well with those expected from mass balance and published fractionation factors. After correcting the observed exchange rates for the dependence of the exchange kinetics on OH- and CO2(aq) activities, the observed overall logarithmic oxygen isotope exchange rates describe a linear relationship with the inverse temperature along with published exchange data that were

  3. Early Holocene human remains from the Argentinean Pampas: additional evidence for distinctive cranial morphology of early South Americans.

    PubMed

    Pucciarelli, Héctor M; Perez, S Ivan; Politis, Gustavo G

    2010-10-01

    The cranial morphology of Early Holocene American human samples is characterized by a long and narrow cranial vault, whereas more recent samples exhibit a shorter and wider cranial vault. Two hypotheses have been proposed to account for the morphological differences between early and late-American samples: (a) the migratory hypothesis that suggests that the morphological variation between early and late American samples was the result of a variable number of migratory waves; and (b) the local diversification hypothesis, that is, the morphological differences between early and late American samples were mainly generated by local, random (genetic drift), and nonrandom factors (selection and phenotypic plasticity). We present the first craniometric study of three early skulls from the Argentinean Pampas, dated ∼8,000 cal. years BP (Arroyo Seco 2, Chocorí, and La Tigra), and one associated with mega-faunal remains (Fontezuelas skull). In addition, we studied several Late Holocene samples. We show that the skulls from the Argentinean Pampas are morphologically similar to other Early Holocene American skulls (i.e., Lagoa Santa from Brazil, Tequendama, Checua, and Aguazuque from Colombia, Lauricocha from Peru, and early Mexicans) that exhibit long and narrow cranial vaults. These samples differ from the Late Holocene American samples that exhibit a shorter and wider cranial vault. Our results underscore the important differences in cranial morphology between early and late-American samples. However, we emphasize the need for further studies to discuss alternative hypotheses regarding such differences.

  4. Prospection and Evaluation of (Hemi) Cellulolytic Enzymes Using Untreated and Pretreated Biomasses in Two Argentinean Native Termites

    PubMed Central

    Ben Guerrero, Emiliano; Arneodo, Joel; Bombarda Campanha, Raquel; Abrão de Oliveira, Patrícia; Veneziano Labate, Mônica T.; Regiani Cataldi, Thaís; Campos, Eleonora; Cataldi, Angel; Labate, Carlos A.; Martins Rodrigues, Clenilson; Talia, Paola

    2015-01-01

    Saccharum officinarum bagasse (common name: sugarcane bagasse) and Pennisetum purpureum (also known as Napier grass) are among the most promising feedstocks for bioethanol production in Argentina and Brazil. In this study, both biomasses were assessed before and after acid pretreatment and following hydrolysis with Nasutitermes aquilinus and Cortaritermes fulviceps termite gut digestome. The chemical composition analysis of the biomasses after diluted acid pretreatment showed that the hemicellulose fraction was partially removed. The (hemi) cellulolytic activities were evaluated in bacterial culture supernatants of termite gut homogenates grown in treated and untreated biomasses. In all cases, we detected significantly higher endoglucanase and xylanase activities using pretreated biomasses compared to untreated biomasses, carboxymethylcellulose and xylan. Several protein bands with (hemi) cellulolytic activity were detected in zymograms and two-dimensional gel electrophoresis. Some proteins of these bands or spots were identified as xylanolytic peptides by mass spectrometry. Finally, the diversity of cultured cellulolytic bacterial endosymbionts associated to both Argentinean native termite species was analyzed. This study describes, for the first time, bacterial endosymbionts and endogenous (hemi) cellulases of two Argentinean native termites as well as their potential application in degradation of lignocellulosic biomass for bioethanol production. PMID:26313257

  5. Psychometric characteristics of the Penn State Worry Questionnaire in an Argentinean sample: a cross-cultural contribution.

    PubMed

    Rodríguez-Biglieri, Ricardo; Vetere, Giselle Lorena

    2011-05-01

    Although studies in several populations have provided support for Penn State Worry Questionnaire (PSQW) reliability and validity, factor analysis studies carried out on different populations show divergent results. The aim of this article is to contribute with the cross-cultural literature on PSWQ. This report describes two studies examining the psychometric characteristics of a revised Argentinean version of the PSWQ. In the first study, items of original PSWQ were translated into Spanish and then back-translated into English. Then, in order to examine its reliability and factorial structure, the instrument was completed by 400 community participants. The second study included two groups of participants as follows: patients with generalized anxiety disorder (GAD), and patients with other anxiety disorders (AC). Results revealed appropriated test-retest reliability over a four-week period, high internal consistency, and good convergent and discriminant validity for PSWQ. In concordance with some results reported in previous studies, a single factorial structure was confirmed for the Argentinean version of PSWQ. By the other hand, a receiver operating characteristic analysis was made to evaluate the ability of PSWQ to discriminate GAD from individuals with others anxiety disorders. A total score of 63 simultaneously optimized sensitivity and specificity in discriminating GAD patients from patients with others anxiety disorders.

  6. Intercultural Bilingual Educational Policies for Transnational Indigenous Communities: School Experiences of the Wichí-Weenhayek People on the Argentinean-Bolivian Border

    ERIC Educational Resources Information Center

    Gates, Zaynab; Román, Diego X.; del Rosal, Karla

    2016-01-01

    Utilizing Ruiz's (1984, 1995) language orientation and language policy work, this ethnographic study compared two intercultural bilingual education (IBE) schools located in two Wichí-Weenhayek communities on both sides of the Argentinean-Bolivian border. We examined Wichí-Weenhayek and non-Indigenous teachers' profiles, teacher-student…

  7. Genome sequence of Sphingomonas sp. S17, isolated from an alkaline, hyperarsenic, and hypersaline volcano-associated lake at high altitude in the Argentinean Puna.

    PubMed

    Farias, Maria Eugenia; Revale, Santiago; Mancini, Estefania; Ordoñez, Omar; Turjanski, Adrian; Cortez, Néstor; Vazquez, Martin P

    2011-07-01

    The high-altitude Andean lakes (HAAL) in the Argentinean Puna-high Andes region represent an almost unexplored ecosystem exposed to extreme conditions (high UV irradiation, hypersalinity, drastic temperature changes, desiccation, and high pH). Here we present the first genome sequence, a Sphingomonas sp., isolated from this extreme environment.

  8. Genome Sequence of Sphingomonas sp. S17, Isolated from an Alkaline, Hyperarsenic, and Hypersaline Volcano-Associated Lake at High Altitude in the Argentinean Puna ▿

    PubMed Central

    Farias, Maria Eugenia; Revale, Santiago; Mancini, Estefania; Ordoñez, Omar; Turjanski, Adrian; Cortez, Néstor; Vazquez, Martin P.

    2011-01-01

    The high-altitude Andean lakes (HAAL) in the Argentinean Puna-high Andes region represent an almost unexplored ecosystem exposed to extreme conditions (high UV irradiation, hypersalinity, drastic temperature changes, desiccation, and high pH). Here we present the first genome sequence, a Sphingomonas sp., isolated from this extreme environment. PMID:21602338

  9. Conventional identification of Streptococcus uberis isolated from bovine mastitis in Argentinean dairy herds.

    PubMed

    Odierno, L; Calvinho, L; Traverssa, P; Lasagno, M; Bogni, C; Reinoso, E

    2006-10-01

    Strep. uberis strains. This conventional scheme can be considered an adequate method for identifying Strep. uberis strains isolated from bovine mastitis because of its affordable cost in developing countries, and it may contribute to determining the frequency of isolation of Strep. uberis strains in Argentinean dairy herds.

  10. DRINKING PATTERNS AND DSM-IV ALCOHOL USE DISORDERS’ CRITERIA IN ARGENTINEAN EMERGENCY DEPARTMENT PATIENTS

    PubMed Central

    Cremonte, Mariana; Cherpitel, Cheryl J.; Borges, Guilherme; Peltzer, Raquel I.; Santángelo, Pablo R.

    2011-01-01

    Background Previous studies have shown cultural variations in normative drinking and furthermore, in the quantity and frequency of drinking related to alcohol use disorders. Aim The main goal of this study is to characterize alcohol drinking patterns in Argentinean Emergency Department patients, and secondly, to explore the association between those drinking patterns and DSM-IV alcohol use disorders. Method Data were collected from a probability sample of patients admitted to the Emergency Department of a large public hospital in Mar del Plata, Argentina. Data analyzed here pertain to those who reported consuming at least one drink during the last twelve months (n=529). A factor analysis of multiple correspondences and a hierarchic classification were performed. For the factor analysis, usual quantity and frequency of drinking (for the last 12 months) were considered active variables; number of DSM-IV dependence criteria met, positive or negative diagnostic status for abuse, positive or negative diagnostic status for dependence (both for the last 12 months), and socio-demographic characteristics (age, gender and economic level) were considered illustrative variables. Results The first five factorial axes were retained, accounting for 88% of the total variance. Hierarchic classification resulted in six distinctive classes of drinking patterns. Two patterns were associated with a positive diagnosis of abuse and dependence, respectively. One, drinking between 4 and 6 drinks per occasion mostly on a weekly basis, was associated with a diagnosis of abuse; this pattern was also associated with meeting one or two dependence criteria (dependence orphans). The other, drinking 7 or more drinks per occasion, was associated with a diagnosis of dependence, and also with a diagnostic orphan condition. This class, composed primarily of males, was not characterized by any particular frequency of drinking. The other four drinking patterns were not associated with a positive

  11. Emended Description of Litomosoides molossi (Nematoda: Onchocercidae) and First Records of Litomosoides Species Parasitizing Argentinean Bats.

    PubMed

    Oviedo, Mirna C; Notarnicola, Juliana; Miotti, M Daniela; Claps, Lucía E

    2016-08-01

    :  During a long-term study on biodiversity of bats in the Yungas and Entre Ríos provinces, 1,304 specimens of bats included in the families Noctilionidae, Phyllostomidae, Vespertilionidae, and Molossidae were collected and checked for filarioids. Litomosoides molossi Esslinger, 1973 was recovered from the thoracic and abdominal cavities of Molossus molossus (prevalence [P] = 6.4%); Litomosoides chandleri Esslinger, 1973 from Artibeus planirostris (P = 6.9%), Sturnira oporaphilum (P = 66.6%), Sturnira erythromos (P = 23.8%), Sturnira lilium (P = 7.2%), and Eumops perotis (P = 50%); and Litomosoides saltensis n. sp. was collected from Eptesicus furinalis (P = 1.7%). In this paper, we emend the description of L. molossi; describe a new species, Litomosoides saltensis n. sp., on the basis of 1 female specimen; and report for the first time L. molossi and L. chandleri parasitizing Argentinean bats, expanding the host and locality records. Litomosoides molossi exhibits a slender buccal capsule, with an anterior segment transparent, and the posterior chitinous portion displays 2 thickenings in the first third; possesses 1 dorsal prominent cephalic papilla and 4 labial papillae distributed around the mouth; cuticle with lateral punctuations all along the hypodermic chords in both sexes; and male with area rugosa and tail without cloacal papillae. In L. chandleri, the lateral punctuations are distributed on the posterior extremity of the body in both sexes. Litomosoides saltensis n. sp. displays a thick buccal capsule with a posterior segment well cuticularized, possessing 2 thickenings in the anterior half; 4 labial and 2 ventral cephalic papillae; a globular vulva located anterior to the esophagus-intestine junction; cuticle with lateral punctuations in the posterior extremity of the body; and tail with salient phasmids. We also provide a taxonomic key for the identification of the Litomosoides sp. of bat dwelling. Long-term studies and large sample sizes are needed

  12. From ideal to real: a longitudinal study of the role of implicit leadership theories on leader-member exchanges and employee outcomes.

    PubMed

    Epitropaki, Olga; Martin, Robin

    2005-07-01

    The results of the present longitudinal study demonstrate the importance of implicit leadership theories (ILTs) for the quality of leader-member exchanges (LMX) and employees' organizational commitment, job satisfaction, and well-being. Results based on a sample of 439 employees who completed the study questionnaires at 2 time points showed that the closer employees perceived their actual manager's profile to be to the ILTs they endorsed, the better the quality of LMX. Results also indicated that the implicit-explicit leadership traits difference had indirect effects on employee attitudes and well-being. These findings were consistent across employee groups that differed in terms of job demand and the duration of manager-employee relation, but not in terms of motivation. Furthermore, crossed-lagged modeling analyses of the longitudinal data explored the possibility of reciprocal effects between implicit-explicit leadership traits difference and LMX and provided support for the initially hypothesized direction of causal effects.

  13. Adulteration of Argentinean milk fats with animal fats: Detection by fatty acids analysis and multivariate regression techniques.

    PubMed

    Rebechi, S R; Vélez, M A; Vaira, S; Perotti, M C

    2016-02-01

    The aims of the present study were to test the accuracy of the fatty acid ratios established by the Argentinean Legislation to detect adulterations of milk fat with animal fats and to propose a regression model suitable to evaluate these adulterations. For this purpose, 70 milk fat, 10 tallow and 7 lard fat samples were collected and analyzed by gas chromatography. Data was utilized to simulate arithmetically adulterated milk fat samples at 0%, 2%, 5%, 10% and 15%, for both animal fats. The fatty acids ratios failed to distinguish adulterated milk fats containing less than 15% of tallow or lard. For each adulterant, Multiple Linear Regression (MLR) was applied, and a model was chosen and validated. For that, calibration and validation matrices were constructed employing genuine and adulterated milk fat samples. The models were able to detect adulterations of milk fat at levels greater than 10% for tallow and 5% for lard.

  14. 36 CFR 902.55 - Intragovernmental exchanges.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., real estate, or facilities, documents exchanged preparatory to anticipated legal proceedings; material... before a court of law, administrative board, hearing officer, or contracting officer. (b) This...

  15. Real-time HD Exchange Kinetics of Proteins from Buffered Aqueous Solution with Electrothermal Supercharging and Top-Down Tandem Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Going, Catherine C.; Xia, Zijie; Williams, Evan R.

    2016-06-01

    Electrothermal supercharging (ETS) with electrospray ionization produces highly charged protein ions from buffered aqueous solutions in which proteins have native folded structures. ETS increases the charge of ribonuclease A by 34%, whereas only a 6% increase in charge occurs for a reduced-alkylated form of this protein, which is unfolded and its structure is ~66% random coil in this solution. These results indicate that protein denaturation that occurs in the ESI droplets is the primary mechanism for ETS. ETS does not affect the extent of solution-phase hydrogen-deuterium exchange (HDX) that occurs for four proteins that have significantly different structures in solution, consistent with a droplet lifetime that is considerably shorter than observable rates of HDX. Rate constants for HDX of ubiquitin are obtained with a spatial resolution of ~1.3 residues with ETS and electron transfer dissociation of the 10+ charge-state using a single capillary containing a few μL of protein solution in which HDX continuously occurs. HDX protection at individual residues with ETS HDX is similar to that with reagent supercharging HDX and with solution-phase NMR, indicating that the high spray potentials required to induce ETS do not lead to HD scrambling.

  16. Development, Validation and Deployment of a Real Time 30 Day Hospital Readmission Risk Assessment Tool in the Maine Healthcare Information Exchange

    PubMed Central

    Hao, Shiying; Wang, Yue; Jin, Bo; Shin, Andrew Young; Zhu, Chunqing; Huang, Min; Zheng, Le; Luo, Jin; Hu, Zhongkai; Fu, Changlin; Dai, Dorothy; Wang, Yicheng; Culver, Devore S.; Alfreds, Shaun T.; Rogow, Todd; Stearns, Frank; Sylvester, Karl G.; Widen, Eric; Ling, Xuefeng B.

    2015-01-01

    Objectives Identifying patients at risk of a 30-day readmission can help providers design interventions, and provide targeted care to improve clinical effectiveness. This study developed a risk model to predict a 30-day inpatient hospital readmission for patients in Maine, across all payers, all diseases and all demographic groups. Methods Our objective was to develop a model to determine the risk for inpatient hospital readmission within 30 days post discharge. All patients within the Maine Health Information Exchange (HIE) system were included. The model was retrospectively developed on inpatient encounters between January 1, 2012 to December 31, 2012 from 24 randomly chosen hospitals, and then prospectively validated on inpatient encounters from January 1, 2013 to December 31, 2013 using all HIE patients. Results A risk assessment tool partitioned the entire HIE population into subgroups that corresponded to probability of hospital readmission as determined by a corresponding positive predictive value (PPV). An overall model c-statistic of 0.72 was achieved. The total 30-day readmission rates in low (score of 0–30), intermediate (score of 30–70) and high (score of 70–100) risk groupings were 8.67%, 24.10% and 74.10%, respectively. A time to event analysis revealed the higher risk groups readmitted to a hospital earlier than the lower risk groups. Six high-risk patient subgroup patterns were revealed through unsupervised clustering. Our model was successfully integrated into the statewide HIE to identify patient readmission risk upon admission and daily during hospitalization or for 30 days subsequently, providing daily risk score updates. Conclusions The risk model was validated as an effective tool for predicting 30-day readmissions for patients across all payer, disease and demographic groups within the Maine HIE. Exposing the key clinical, demographic and utilization profiles driving each patient’s risk of readmission score may be useful to providers

  17. Temporal Diversity and Abundance Patterns of Parasitoids of Fruit-Infesting Tephritidae (Diptera) in the Argentinean Yungas: Implications for Biological Control.

    PubMed

    Schliserman, Pablo; Aluja, Martin; Rull, Juan; Ovruski, Sergio M

    2016-10-01

    A 4-yr study was done to analyze seasonal patterns underlying host plant-fruit fly-parasitoid interactions in a secondary forest in the Argentinean Yunga and its importance for the implementation of conservation and augmentative biological control. Larval-pupal hymenopteran parasitoids associated with all host plants and fruit fly species were identified and the seasonal occurrence of fruit, infestation levels, parasitism percentage, and relative parasitoid abundance were determined. Three fruit fly species in two genera were found in association with surveyed plants, two of which (Ceratitis capitata (Wiedemann) and Anastrepha fraterculus (Wiedemann)) are of major economic importance. Infestation levels were strongly influenced by environmental factors and peak fruit availability. Five fruit fly parasitoid species were recovered from fly pupae, four braconid species, and one figitid. Time windows for fruit fly population growth were pinpointed. Based on results, the present analysis proposes an effective fruit fly biological control strategy tailored for the northwestern Argentinean citrus-producing area.

  18. Phylogenetic analyses of typical bovine rotavirus genotypes G6, G10, P[5] and P[11] circulating in Argentinean beef and dairy herds.

    PubMed

    Badaracco, A; Garaicoechea, L; Matthijnssens, J; Louge Uriarte, E; Odeón, A; Bilbao, G; Fernandez, F; Parra, G I; Parreño, V

    2013-08-01

    Group A rotavirus (RVA) is one of the main causes of neonatal calf diarrhea worldwide. RVA strains affecting Argentinean cattle mainly possess combinations of the G6, G10, P[5] and P[11] genotypes. To determine RVA diversity among Argentinean cattle, representative bovine RVA strains detected in diarrheic calves were selected from a survey conducted during 1997-2009. The survey covered the main livestock regions of the country from dairy and beef herds. Different phylogenetic approaches were used to investigate the genetic evolution of RVA strains belonging to the prevalent genotypes. The nucleotide phylogenetic tree showed that all genotypes studied could be divided into several lineages. Argentinean bovine RVA strains were distributed across multiple lineages and most of them were distinct from the lineage containing the vaccine strains. Only the aminoacid phylogenetic tree of G6 RVA strains maintained the same lineages as observed at the nucleotide level, whereas a different clustering pattern was observed for the aminoacid phylogenetic trees of G10, P[5] and P[11] suggesting that the strains are more closely related at the aminoacid level than G6 strains. Association between P[5] and G6(IV), prevalent in beef herd, and between P[11] and G6(III) or G10 (VI and V), prevalent in dairy herds, were found. In addition, Argentinean G6(III), G10, P[5] and P[11] bovine RVA strains grouped together with human strains, highlighting their potential for zoonotic transmission. Phylogenetic studies of RVA circulating in animals raised for consumption and in close contact with humans, such as cattle, contribute to a better understanding of the epidemiology of the RVA infection and evolution.

  19. Second-order capillary electrophoresis diode array detector data modeled with the Tucker3 algorithm: A novel strategy for Argentinean white wine discrimination respect to grape variety.

    PubMed

    Azcarate, Silvana M; de Araújo Gomes, Adriano; Vera-Candioti, Luciana; Cesar Ugulino de Araújo, Mário; Camiña, José M; Goicoechea, Héctor C

    2016-07-01

    Data obtained by capillary electrophoresis with diode array detection (CE-DAD) were modeled with the purpose to discriminate Argentinean white wines samples produced from three grape varieties (Torrontés, Chardonnay, and Sauvignon blanc). Thirty-eight samples of commercial white wine from four wine-producing provinces of Argentina (Mendoza, San Juan, Salta, and Rio Negro) were analyzed. CE-DAD matrices with dimensions of 421 elution times (from 1.17 to 7.39 minutes) × 71 wavelengths (from 227 to 367 nm) were joined in a three way data array and decomposed by Tucker3 method under non-negativity constraint, employing 18, 18 and six factors in the modes 1, 2 and 3, respectively. Using the scores of Tucker model, it was possible to discriminate samples of Argentinean white wine by linear discriminant analysis and Kernel linear discriminant analysis. Core element analysis of the Tucker3 model allows identifying the loading profiles in spectral mode related to Argentinean white wine samples.

  20. First report of isolation and molecular characterization of bubaline herpesvirus 1 (BuHV1) from Argentinean water buffaloes.

    PubMed

    Maidana, Silvina S; Konrad, José L; Craig, María I; Zabal, Osvaldo; Mauroy, Axel; Thiry, Etienne; Crudeli, Gustavo; Romera, Sonia A

    2014-11-01

    Herpesviruses have mainly co-evolved with their hosts for millions of years. However, bovine herpesvirus 1 (BoHV1) and related ruminant alphaherpesviruses have been reported to cross the species barrier. Bubaline herpesvirus 1 (BuHV1) is an alphaherpesvirus closely related to BoHV1 and BoHV5. According to the serological cross-relationships between ruminant alphaherpesviruses, several surveys have studied the occurrence of BoHV1-related virus infection in wild and domestic ruminant species. Recent studies in Argentina showed an increase in serological prevalence against BoHV1 related viruses in water buffaloes (Bubalus bubalis) population. The aim of this study was to investigate the presence of related ruminant alphaherpesvirus in the Argentinean water buffalo population. BuHV1 was successfully isolated from 5 out of 225 buffaloes analyzed. One isolate was obtained from nasal secretions, and the others were from vaginal swabs. The buffaloes belonged to four different farms located in northeastern Argentina. The isolates were characterized as alphaherpesvirus by direct immunofluorescence using FITC-anti-BoHV1 IgG. Restriction analysis performed with BamHI and BstEII on the complete genome showed differences between the isolates and those from BoHV1 and BoHV5 subtypes. Phylogenetic analysis on both UL27 and US6 showed similarity in tree topology. While three of the isolates grouped together with sequences of BoHV5, two other isolates clustered separately. Genetic analysis of eight concatenated sequences from all isolates and references strains showed high nucleotide sequence identity between BuHV1 and BoHV5. While three of the isolates clustered together with the BoHV5 reference strain, the last two isolates were closely related to an Australian BuHV1 strain. To our knowledge, this is the first report on the isolation and molecular characterization of BuHV1 in South America. Phylogenetic analysis suggested that two different BuHV1 lineages circulate in the

  1. Fluorescent nanosensors for intracellular chemical analysis: decyl methacrylate liquid polymer matrix and ion-exchange-based potassium PEBBLE sensors with real-time application to viable rat C6 glioma cells.

    PubMed

    Brasuel, M; Kopelman, R; Miller, T J; Tjalkens, R; Philbert, M A

    2001-05-15

    Fluorescent spherical nanosensors, or PEBBLEs (probes encapsulated by biologically localized embedding), in the 500 nm-1 microm size range have been developed using decyl methacrylate as a matrix. A general scheme for the polymerization and introduction of sensing components creates a matrix that allows for the utilization of the highly selective ionophores used in poly(vinyl chloride) and decyl methacrylate ion-selective electrodes. We have applied these optically silent ionophores to fluorescence-based sensing by using ion-exchange and highly selective pH chromoionophores. This allows the tailoring of selective submicrometer sensors for use in intracellular measurements of important analytes for which selective enough fluorescent probes do not exist. The protocol for sensor development has been worked out for potassium sensing. It is based on the BME-44 ionophore (2-dodecyl-2-methyl-1,3-propanediylbis[N-[5'nitro(benzo-15-crown-5)-4'-yl]carbamate]). The general scheme should work for any available ionophore used in PVC or decyl methacrylate ion-selective electrodes, with minor adjustments to account for differences in ionophore charge and analyte binding constant. The reversible and highly selective sensors developed have a subsecond response time and an adjustable dynamic range. Applications to live C6 glioma cells demonstrate their utility; the intracellular potassium activity is followed in real time upon extracellular administration of kainic acid.

  2. The Mental Health Continuum-Short Form (MHC-SF) in the Argentinean Context: Confirmatory Factor Analysis and Measurement Invariance.

    PubMed

    Lupano Perugini, María Laura; de la Iglesia, Guadalupe; Castro Solano, Alejandro; Keyes, Corey Lee M

    2017-03-01

    The present research aimed at studying the psychometric properties of the Mental Health Continuum-Short Form (MHC-SF; Keyes, 2005) in a sample of 1,300 Argentinean adults (50% males; 50% females). Their mean age was 40.28 years old (SD = 13.59). The MHC-SF is a 14 item test that assesses three components (i.e., emotional, social, and psychological) of well-being. Convergent and divergent evidence of construct validity was assessed by conducting confirmatory factor analysis, cross-validation, factorial invariance, and correlations with external criteria. Internal consistency was studied using Cronbach's alphas. Results indicated an adequate fit of a three-dimensional model. This structure was also confirmed, and was invariant throughout sex and age. The emotional well-being scores converged with life satisfaction and positive affect measures; the psychological well-being scale had a positive association with the presence of meaning in life; and the social well-being scores showed a positive and strong correlation with an external measure of well-being. Also, all scores were negatively associated with negative affect, search of meaning in life, and presence of depression symptoms. Internal consistency was .89 for the MHC-SF. Furthermore, the findings supported the two - continua model of mental health.

  3. Diagnosis and Molecular Variability of an Argentinean Population of Nacobbus aberrans with Some Observations on Histopathology in Tomato

    PubMed Central

    Vovlas, N.; Nico, A. I.; De Luca, F.; De Giorgi, C.; Castillo, P.

    2007-01-01

    Diagnosis of an Argentinean population of Nacobbus sp. infecting sweet pepper (lamuyo) was carried out including morphology, scanning electron microscopy, and molecular studies. In light of our morphometric, molecular and host-range results, we consider the studied population to belong to N. aberrans s. l., and by host range tests the population is assigned to the "sugar beet group." ITS-PCR analysis on individual male and immature female specimens of this population yielded amplification products of approximately 922 bp. RFLP profiles and sequencing of the ITS region revealed that, in addition to the host group, the present population can be assigned to the "Argentina 2" group. Disease development and histopathology were investigated with glasshouse observations using tomato, pepper, sugar beet and potato seedlings exposed to nematode infection for 45 days at 28 ± 2°C. Histopathology of tomato roots confirmed that all immature stages and young females and males are migratory, whereas mature females are obligate sedentary endoparasites. Rather than syncytia, large regions of cortical necrosis and cavities were detected in tomato swellings infected by juveniles. However, syncytia were associated only with adult females. Large root galls, hyperplasia, abnormal proliferation of lateral roots and asymmetry of root structure were common anatomical changes induced by the nematode feeding in tomato roots. PMID:19259470

  4. The Mental Health Continuum–Short Form (MHC–SF) in the Argentinean Context: Confirmatory Factor Analysis and Measurement Invariance

    PubMed Central

    Lupano Perugini, María Laura; de la Iglesia, Guadalupe; Castro Solano, Alejandro; Keyes, Corey Lee M.

    2017-01-01

    The present research aimed at studying the psychometric properties of the Mental Health Continuum–Short Form (MHC–SF; Keyes, 2005) in a sample of 1,300 Argentinean adults (50% males; 50% females). Their mean age was 40.28 years old (SD = 13.59). The MHC–SF is a 14 item test that assesses three components (i.e., emotional, social, and psychological) of well-being. Convergent and divergent evidence of construct validity was assessed by conducting confirmatory factor analysis, cross-validation, factorial invariance, and correlations with external criteria. Internal consistency was studied using Cronbach’s alphas. Results indicated an adequate fit of a three-dimensional model. This structure was also confirmed, and was invariant throughout sex and age. The emotional well-being scores converged with life satisfaction and positive affect measures; the psychological well-being scale had a positive association with the presence of meaning in life; and the social well-being scores showed a positive and strong correlation with an external measure of well-being. Also, all scores were negatively associated with negative affect, search of meaning in life, and presence of depression symptoms. Internal consistency was .89 for the MHC–SF. Furthermore, the findings supported the two - continua model of mental health. PMID:28344677

  5. Linking soil, water, and honey composition to assess the geographical origin of argentinean honey by multielemental and isotopic analyses.

    PubMed

    Baroni, María V; Podio, Natalia S; Badini, Raúl G; Inga, Marcela; Ostera, Héctor A; Cagnoni, Mariana; Gautier, Eduardo A; García, Pilar Peral; Hoogewerff, Jurian; Wunderlin, Daniel A

    2015-05-13

    The objective of this research was to investigate the development of a reliable fingerprint from elemental and isotopic signatures of Argentinean honey to assess its geographical provenance. Honey, soil, and water from three regions (Córdoba, Buenos Aires, and Entre Rı́os) were collected. The multielemental composition was determined by ICP-MS. δ(13)C was measured by isotopic ratio mass spectrometry, whereas the (87)Sr/(86)Sr ratio was determined using thermal ionization mass spectrometry. The data were analyzed by chemometrics looking for the association between the elements, stable isotopes, and honey samples from the three studied areas. Honey samples were differentiated by classification trees and discriminant analysis using a combination of eight key variables (Rb, K/Rb, B, U, (87)Sr/(86)Sr, Na, La, and Zn) presenting differences among the studied regions. The application of canonical correlation analysis and generalized procrustes analysis showed 91.5% consensus between soil, water, and honey samples, in addition to clear differences between studied areas. To the authors' knowledge, this is the first report demonstrating the correspondence between soil, water, and honey samples using different statistical methods, showing that elemental and isotopic honey compositions are related to soil and water characteristics of the site of origin.

  6. Real Earthquakes, Real Learning

    ERIC Educational Resources Information Center

    Schomburg, Aaron

    2003-01-01

    One teacher took her class on a year long earthquake expedition. The goal was to monitor the occurrences of real earthquakes during the year and mark their locations with push pins on a wall-sized world map in the hallway outside the science room. The purpose of the project was to create a detailed picture of the earthquakes that occurred…

  7. Atrazine and metribuzin sorption in soils of the Argentinean humid pampas.

    PubMed

    Daniel, Peter E; Bedmar, Francisco; Costa, José L; Aparicio, Virginia C

    2002-12-01

    Laboratory studies were conducted to determine the influence of surface and subsurface properties of three representative soils of the humid pampas of Argentina on atrazine and metribuzin sorption. Atrazine and metribuzin sorption isotherms were constructed for each soil at four depths. Sorption affinity of herbicides was approximated by the Freundlich constant (K(f)), distribution coefficient (Kd), and the normalized Kd based on organic carbon content (K(oc)). Multiple regression of the sorption constants against selected soil properties indicated that organic carbon content (OC) and silt were related positively and negatively, respectively, to atrazine K(f) coefficient (r2 = 0.93), while Kd coefficient of atrazine was related positively to organic carbon content and negatively to both silt and cation exchange capacity (CEC) (r2 = 0.96). For metribuzin, only organic matter content was related positively to Kr coefficient (r2 = 0.51). Lower K(f) values for atrazine were obtained for all soils with increasing depth, indicating lesser sorption at greater depths. Metribuzin sorption was quite similar across all depths. Sorption constant K(f) of atrazine ranged from 2.06 to 7.82, while metribuzin K(f) values ranged from 1.8 to 3.52 and were lower than atrazine for all soils and depths, indicating a greater leaching potential across the soil profile.

  8. Areal Changes of Lentic Water Bodies Within an Agricultural Basin of the Argentinean Pampas. Disentangling Land Management from Climatic Causes

    NASA Astrophysics Data System (ADS)

    Booman, Gisel Carolina; Calandroni, Mirta; Laterra, Pedro; Cabria, Fabián; Iribarne, Oscar; Vázquez, Pablo

    2012-12-01

    Wetland loss is a frequent concern for the environmental management of rural landscapes, but poor disentanglement between climatic and land management causes frequently constrains both proper diagnoses and planning. The aim of this study is to address areal changes induced by non-climatic factors on lentic water bodies (LWB) within an agricultural basin of the Argentinean Pampas, and the human activities that might be involved. The LWB of the Mar Chiquita basin (Buenos Aires province, Argentina) were mapped using Landsat images from 1998-2008 and then corrected for precipitation variability by considering the regional hydrological status on each date. LWB areal changes were statistically and spatially analyzed in relation to land use changes, channelization of streams, and drainage of small SWB in the catchment areas. We found that 12 % of the total LWB in the basin had changed ( P < 0.05) due to non-climatic causes. During the evaluated decade, 30 % of the LWB that changed size had decreased while 70 % showed steady increases in area. The number of altered LWB within watersheds lineally increased or decreased according to the proportion of grasslands replaced by sown pastures, or the proportion of sown pastures replaced by crop fields, respectively. Drainage and channelization do not appear to be related to the alteration of LWB; however some of these hydrologic modifications may predate 1998, and thus earlier effects cannot be discarded. This study shows that large-scale changes in land cover (e.g., grasslands reduction) can cause a noticeable loss of hydrologic regulation at the catchment scale within a decade.

  9. Acute retroviral syndrome and high baseline viral load are predictors of rapid HIV progression among untreated Argentinean seroconverters

    PubMed Central

    2011-01-01

    Background Diagnosis of primary HIV infection (PHI) has important clinical and public health implications. HAART initiation at this stage remains controversial. Methods Our objective was to identify predictors of disease progression among Argentinean seroconverters during the first year of infection, within a multicentre registry of PHI-patients diagnosed between 1997 and 2008. Cox regression was used to analyze predictors of progression (LT-CD4 < 350 cells/mm3, B, C events or death) at 12 months among untreated patients. Results Among 134 subjects, 74% presented with acute retroviral syndrome (ARS). Seven opportunistic infections (one death), nine B events, and 10 non-AIDS defining serious events were observed. Among the 92 untreated patients, 24 (26%) progressed at 12 months versus three (7%) in the treated group (p = 0.01). The 12-month progression rate among untreated patients with ARS was 34% (95% CI 22.5-46.3) versus 13% (95% CI 1.1-24.7) in asymptomatic patients (p = 0.04). In univariate analysis, ARS, baseline LT-CD4 < 350 cells/mm3, and baseline and six-month viral load (VL) > 100,000 copies/mL were associated with progression. In multivariate analysis, only ARS and baseline VL > 100,000 copies/mL remained independently associated; HR: 8.44 (95% CI 0.97-73.42) and 9.44 (95% CI 1.38-64.68), respectively. Conclusions In Argentina, PHI is associated with significant morbidity. HAART should be considered in PHI patients with ARS and high baseline VL to prevent disease progression. PMID:21831310

  10. Bordetella pertussis Isolates from Argentinean Whooping Cough Patients Display Enhanced Biofilm Formation Capacity Compared to Tohama I Reference Strain

    PubMed Central

    Arnal, Laura; Grunert, Tom; Cattelan, Natalia; de Gouw, Daan; Villalba, María I.; Serra, Diego O.; Mooi, Frits R.; Ehling-Schulz, Monika; Yantorno, Osvaldo M.

    2015-01-01

    Pertussis is a highly contagious disease mainly caused by Bordetella pertussis. Despite the massive use of vaccines, since the 1950s the disease has become re-emergent in 2000 with a shift in incidence from infants to adolescents and adults. Clearly, the efficacy of current cellular or acellular vaccines, formulated from bacteria grown in stirred bioreactors is limited, presenting a challenge for future vaccine development. For gaining insights into the role of B. pertussis biofilm development for host colonization and persistence within the host, we examined the biofilm forming capacity of eight argentinean clinical isolates recovered from 2001 to 2007. All clinical isolates showed an enhanced potential for biofilm formation compared to the reference strain Tohama I. We further selected the clinical isolate B. pertussis 2723, exhibiting the highest biofilm biomass production, for quantitative proteomic profiling by means of two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) coupled with mass spectrometry, which was accompanied by targeted transcriptional analysis. Results revealed an elevated expression of several virulence factors, including adhesins involved in biofilm development. In addition, we observed a higher expression of energy metabolism enzymes in the clinical isolate compared to the Tohama I strain. Furthermore, all clinical isolates carried a polymorphism in the bvgS gene. This mutation was associated to an increased sensitivity to modulation and a faster rate of adhesion to abiotic surfaces. Thus, the phenotypic biofilm characteristics shown by the clinical isolates might represent an important, hitherto underestimated, adaptive strategy for host colonization and long time persistence within the host. PMID:26696973

  11. Bordetella pertussis Isolates from Argentinean Whooping Cough Patients Display Enhanced Biofilm Formation Capacity Compared to Tohama I Reference Strain.

    PubMed

    Arnal, Laura; Grunert, Tom; Cattelan, Natalia; de Gouw, Daan; Villalba, María I; Serra, Diego O; Mooi, Frits R; Ehling-Schulz, Monika; Yantorno, Osvaldo M

    2015-01-01

    Pertussis is a highly contagious disease mainly caused by Bordetella pertussis. Despite the massive use of vaccines, since the 1950s the disease has become re-emergent in 2000 with a shift in incidence from infants to adolescents and adults. Clearly, the efficacy of current cellular or acellular vaccines, formulated from bacteria grown in stirred bioreactors is limited, presenting a challenge for future vaccine development. For gaining insights into the role of B. pertussis biofilm development for host colonization and persistence within the host, we examined the biofilm forming capacity of eight argentinean clinical isolates recovered from 2001 to 2007. All clinical isolates showed an enhanced potential for biofilm formation compared to the reference strain Tohama I. We further selected the clinical isolate B. pertussis 2723, exhibiting the highest biofilm biomass production, for quantitative proteomic profiling by means of two-dimensional fluorescence difference gel electrophoresis (2D-DIGE) coupled with mass spectrometry, which was accompanied by targeted transcriptional analysis. Results revealed an elevated expression of several virulence factors, including adhesins involved in biofilm development. In addition, we observed a higher expression of energy metabolism enzymes in the clinical isolate compared to the Tohama I strain. Furthermore, all clinical isolates carried a polymorphism in the bvgS gene. This mutation was associated to an increased sensitivity to modulation and a faster rate of adhesion to abiotic surfaces. Thus, the phenotypic biofilm characteristics shown by the clinical isolates might represent an important, hitherto underestimated, adaptive strategy for host colonization and long time persistence within the host.

  12. Assessment of Argentinean Patagonia pollution: PBDEs, OCPs and PCBs in different matrices from the Río Negro basin.

    PubMed

    Miglioranza, Karina S B; Gonzalez, Mariana; Ondarza, Paola M; Shimabukuro, Valeria M; Isla, Federico I; Fillmann, Gilberto; Aizpún, Julia E; Moreno, Víctor J

    2013-05-01

    This work reports the occurrence and distribution of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in soil, sediment, suspended particle matter (SPM), streamwater and macrophytes, along the Río Negro basin, Argentinean Patagonia. The clear predominance of OCPs among all matrices indicates the impact of agriculture on the watershed. The highest levels were found for pp'-DDE which represented up to 95% in agricultural soils (42.0-1.27x10(3) ng/g d.w) from the Upper Valley (upstream), where long and historical intensive fruit cultures have been settled and represent a hot spot of legacy pesticides for the environment. The insecticide endosulfan, currently in use, was also found in all matrices. Levels ranged between 0.3 and 708.0 ng/g d.w, being the highest concentrations those of SPM from the Middle Valley, just before the delta area, where pesticides would be retained leading to lower concentrations as was observed downstream. PCB (#153, 138, 110, 101) and PBDE (BDE-47) levels were directly related with the presence of hydroelectric power plants, dams and dumping sites, mainly settled in the Upper Valley (0.8 ng/g and 15.1 ng/g d.w for PBDEs and PCBs, respectively). Although there was a decreasing gradient of these pollutant concentrations through the river flow, downstream urban areas enhanced PCB concentrations in the aquatic environment. More efforts and monitoring programs are highly required to control and reduce soil erosion in order to prevent the availability of forbidden pollutants in the environment.

  13. Exchange Network

    EPA Pesticide Factsheets

    The Environmental Information Exchange Network (EIEN) is an Internet-based system used by state, tribal and territorial partners to securely share environmental and health information with one another and EPA.

  14. Gas exchange

    MedlinePlus Videos and Cool Tools

    ... during exhalation. Gas exchange is the delivery of oxygen from the lungs to the bloodstream, and the ... share a membrane with the capillaries in which oxygen and carbon dioxide move freely between the respiratory ...

  15. HEAT EXCHANGER

    DOEpatents

    Fox, T.H. III; Richey, T. Jr.; Winders, G.R.

    1962-10-23

    A heat exchanger is designed for use in the transfer of heat between a radioactive fiuid and a non-radioactive fiuid. The exchanger employs a removable section containing the non-hazardous fluid extending into the section designed to contain the radioactive fluid. The removable section is provided with a construction to cancel out thermal stresses. The stationary section is pressurized to prevent leakage of the radioactive fiuid and to maintain a safe, desirable level for this fiuid. (AEC)

  16. Molecular analysis of HEXA gene in Argentinean patients affected with Tay-Sachs disease: possible common origin of the prevalent c.459+5A>G mutation.

    PubMed

    Zampieri, Stefania; Montalvo, Annalisa; Blanco, Mariana; Zanin, Irene; Amartino, Hernan; Vlahovicek, Kristian; Szlago, Marina; Schenone, Andrea; Pittis, Gabriela; Bembi, Bruno; Dardis, Andrea

    2012-05-15

    Tay-Sachs disease (TSD) is a recessively inherited disorder caused by the deficient activity of hexosaminidase A due to mutations in the HEXA gene. Up to date there is no information regarding the molecular genetics of TSD in Argentinean patients. In the present study we have studied 17 Argentinean families affected by TSD, including 20 patients with the acute infantile form and 3 with the sub-acute form. Overall, we identified 14 different mutations accounting for 100% of the studied alleles. Eight mutations were novel: 5 were single base changes leading to drastic residue changes or truncated proteins, 2 were small deletions and one was an intronic mutation that may cause a splicing defect. Although the spectrum of mutations was highly heterogeneous, a high frequency of the c.459+5G>A mutation, previously described in different populations was found among the studied cohort. Haplotype analysis suggested that in these families the c.459+5G>A mutation might have arisen by a single mutational event.

  17. Heat exchanger

    DOEpatents

    Daman, Ernest L.; McCallister, Robert A.

    1979-01-01

    A heat exchanger is provided having first and second fluid chambers for passing primary and secondary fluids. The chambers are spaced apart and have heat pipes extending from inside one chamber to inside the other chamber. A third chamber is provided for passing a purge fluid, and the heat pipe portion between the first and second chambers lies within the third chamber.

  18. Real Language Meets Real Business

    ERIC Educational Resources Information Center

    Muirhead, Muirhead; Schechter, Sarah

    2016-01-01

    The Real Business Language Challenge was a collaborative pilot project between Coca-Cola Enterprises (CCE) and Routes into Languages East for Year 9 and 10 pupils. It was based on CCE's award-winning Real Business Challenge, part of its highly acclaimed education programme. The Real Business Language Challenge transformed the project into a…

  19. Biomonitoring of TBT contamination and imposex incidence along 4700 km of Argentinean shoreline (SW Atlantic: from 38S to 54S).

    PubMed

    Bigatti, Gregorio; Primost, Mónica A; Cledón, Maximiliano; Averbuj, Andrés; Theobald, Norbert; Gerwinski, Wolfgang; Arntz, Wolf; Morriconi, Elba; Penchaszadeh, Pablo E

    2009-05-01

    The imposex incidence and TBT pollution were investigated along 4,700km of Argentinean coast, including city harbors and proximal zones without marine traffic. We analyzed 1805 individuals from 12 gastropod species, including families Volutidae, Muricidae, Nassariidea, Calyptraidae, Marginellidae, and Buccinidae, and found the imposex phenomenon for the first time in six species. In high marine traffic zones, TBT pollution was registered and the percentage of imposex was high, while these occurrences were null in areas without boat traffic. The species that best reflect the degree of imposex were those inhabiting sandy/muddy or mixed bottoms. TBT determination and imposex incidence indicate that pollution was focused only in ports with high marine traffic or in areas where ship hulls are painted. This is the first report of an imposex-sediment approach to evaluate organotin contamination along the coast of a South American country.

  20. Seasonal variation of temporal niche in wild owl monkeys (Aotus azarai azarai) of the Argentinean Chaco: a matter of masking?

    PubMed

    Erkert, Hans G; Fernandez-Duque, Eduardo; Rotundo, Marcelo; Scheideler, Angelika

    2012-07-01

    nighttime activity occurred in summer and maximal daytime activity during the cold winter months. Dusk and dawn activity, which together accounted for 43% of the total daily activity, barely changed. The monkeys tended to terminate their nightly activity period earlier on warm and rainy days, whereas the daily amount of activity showed no significant correlation either with temperature or precipitation. These data are consistent with the dual-oscillator hypothesis of circadian regulation. They suggest the seasonal variations of the timing and pattern of daily activity in wild owl monkeys of the Argentinean Chaco result from a specific interplay of light entrainment of circadian rhythmicity and strong masking effects of various endogenous and environmental factors. Since the phase position of the monkeys' evening and morning activity peaks did not vary considerably over the year, the seasonal change from a crepuscular/nocturnal activity pattern in summer to a more crepuscular/cathemeral one in winter does not depend on a corresponding phase shift of the entrained circadian rhythm, but mainly on masking effects. Thermoregulatory and energetic demands and constraints seem to play a crucial role.

  1. 33 CFR 211.12 - Exchange of lands.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Exchange of lands. 211.12 Section... of Real Estate Acquired for Civil Works Purposes § 211.12 Exchange of lands. The Secretary of the Army is authorized to exchange lands acquired for river and harbor and flood control projects...

  2. 33 CFR 211.12 - Exchange of lands.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Exchange of lands. 211.12 Section... of Real Estate Acquired for Civil Works Purposes § 211.12 Exchange of lands. The Secretary of the Army is authorized to exchange lands acquired for river and harbor and flood control projects...

  3. Heat exchanger

    DOEpatents

    Brackenbury, Phillip J.

    1986-04-01

    A heat exchanger comparising a shell attached at its open end to one side of a tube sheet and a detachable head connected to the other side of said tube sheet. The head is divided into a first and second chamber in fluid communication with a nozzle inlet and nozzle outlet, respectively, formed in said tube sheet. A tube bundle is mounted within said shell and is provided with inlets and outlets formed in said tube sheet in communication with said first and second chambers, respectively.

  4. Segmented heat exchanger

    DOEpatents

    Baldwin, Darryl Dean; Willi, Martin Leo; Fiveland, Scott Byron; Timmons, Kristine Ann

    2010-12-14

    A segmented heat exchanger system for transferring heat energy from an exhaust fluid to a working fluid. The heat exchanger system may include a first heat exchanger for receiving incoming working fluid and the exhaust fluid. The working fluid and exhaust fluid may travel through at least a portion of the first heat exchanger in a parallel flow configuration. In addition, the heat exchanger system may include a second heat exchanger for receiving working fluid from the first heat exchanger and exhaust fluid from a third heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the second heat exchanger in a counter flow configuration. Furthermore, the heat exchanger system may include a third heat exchanger for receiving working fluid from the second heat exchanger and exhaust fluid from the first heat exchanger. The working fluid and exhaust fluid may travel through at least a portion of the third heat exchanger in a parallel flow configuration.

  5. Real Forestry for Real Estate

    ERIC Educational Resources Information Center

    Gagnon, Jennifer; Fisher, Jason

    2013-01-01

    Virginia is poised to see an unprecedented change in forest land ownership. To provide new landowners with information on sustainable forest management, we developed a two-part program, Real Forestry for Real Estate. First, we assembled New Landowner Packets, which contain a variety of sustainable forest management resources. Second, two…

  6. Educator Exchange Resource Guide.

    ERIC Educational Resources Information Center

    Garza, Cris; Rodriguez, Victor

    This resource guide was developed for teachers and administrators interested in participating in intercultural and international exchange programs or starting an exchange program. An analysis of an exchange program's critical elements discusses exchange activities; orientation sessions; duration of exchange; criteria for participation; travel,…

  7. 76 FR 13691 - Self-Regulatory Organizations; C2 Options Exchange, Incorporated: Notice of Filing and Immediate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-14

    ... to provide to users of the Exchange real-time analytical tools to measure the latency of orders to... RaceTeam latency measurement service for the Exchange's systems. The Exchange will not bill or contract... Exchange extranet. The RaceTeam product offering does not measure latency outside of the Exchange...

  8. Corrosive resistant heat exchanger

    DOEpatents

    Richlen, Scott L.

    1989-01-01

    A corrosive and errosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is conveyed through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium.

  9. Exchange frequency in replica exchange molecular dynamics

    NASA Astrophysics Data System (ADS)

    Sindhikara, Daniel; Meng, Yilin; Roitberg, Adrian E.

    2008-01-01

    The effect of the exchange-attempt frequency on sampling efficiency is studied in replica exchange molecular dynamics (REMD). We show that sampling efficiency increases with increasing exchange-attempt frequency. This conclusion is contrary to a commonly expressed view in REMD. Five peptides (1-21 residues long) are studied with a spectrum of exchange-attempt rates. Convergence rates are gauged by comparing ensemble properties between fixed length test REMD simulations and longer reference simulations. To show the fundamental correlation between exchange frequency and convergence time, a simple model is designed and studied, displaying the same basic behavior of much more complex systems.

  10. Real Heroes.

    ERIC Educational Resources Information Center

    Denenberg, Dennis

    2001-01-01

    Presents stories taken from the book, "50 American Heroes Every Kid Should Meet," explaining that children need to learn about the value of real-life human accomplishments (versus those of athletes, television personalities, and rock stars). The heroes include Elizabeth Blackwell, first American woman doctor; George C. Marshall,…

  11. Interphase cytogenetic analysis in Argentinean B-cell chronic lymphocytic leukemia patients: association of trisomy 12 and del(13q14).

    PubMed

    Chena, Christian; Arrossagaray, Guillermo; Scolnik, Mariano; Palacios, María F; Slavutsky, Irma

    2003-10-15

    We have evaluated genomic aberrations by conventional cytogenetics and fluorescence in situ hybridization (FISH) analysis in a series of 57 Argentinean B-cell chronic lymphocytic leukemia (B-CLL) patients. The studies were performed on stimulated peripheral blood lymphocytes. FISH analysis for trisomy 12, 13q14 deletion, and monosomy of TP53 (also known as p53) was performed according to standard protocols. Our results showed 46.3% of patients with clonal chromosomal alterations by conventional cytogenetics and 80.7% by FISH. Trisomy 12 was found in 21.9% of patients by G-banding analysis and in 35% by FISH studies. Allelic loss of 13q14 was observed in 63.2% patients, most of them showing D13S319 and D13S25 deletion; 11% of patients showed TP53 monosomy. Coexistence of trisomy 12 and 13q14 deletion was found in 17.5% of patients. In this group, deletion 13q14 was the prevalent clone, with percentages 25-35% higher than those observed for trisomy 12, suggesting clonal evolution. The coexistence of trisomy 12 with deletion 13q14 was observed in a higher frequency than reported in the literature. A probable adverse prognosis is suggested for this group of patients, likely related to clonal evolution.

  12. Genotypic Characterization of Azotobacteria Isolated from Argentinean Soils and Plant-Growth-Promoting Traits of Selected Strains with Prospects for Biofertilizer Production

    PubMed Central

    Rubio, Esteban Julián; Cassán, Fabricio Darío

    2013-01-01

    The genetic diversity among 31 putative Azotobacter isolates obtained from agricultural and non-agricultural soils was assessed using rep-PCR genomic fingerprinting and identified to species level by ARDRA and partial 16S rRNA gene sequence analysis. High diversity was found among the isolates, identified as A. chroococcum, A. salinestris, and A. armeniacus. Selected isolates were characterized on the basis of phytohormone biosynthesis, nitrogenase activity, siderophore production, and phosphate solubilization. Indole-3 acetic-acid (IAA), gibberellin (GA3) and zeatin (Z) biosynthesis, nitrogenase activity, and siderophore production were found in all evaluated strains, with variation among them, but no phosphate solubilization was detected. Phytohormones excreted to the culture medium ranged in the following concentrations: 2.2–18.2 μg IAA mL−1, 0.3–0.7 μg GA3 mL−1, and 0.5–1.2 μg Z mL−1. Seed inoculations with further selected Azotobacter strains and treatments with their cell-free cultures increased the number of seminal roots and root hairs in wheat seedlings. This latter effect was mimicked by treatments with IAA-pure solutions, but it was not related to bacterial root colonization. Our survey constitutes a first approach to the knowledge of Azotobacter species inhabiting Argentinean soils in three contrasting geographical regions. Moreover, this phenotypic characterization constitutes an important contribution to the selection of Azotobacter strains for biofertilizer formulations. PMID:24302859

  13. Construction and first atmospheric observations of a high spectral resolution lidar system in Argentina in the frame of a trinational Japanese-Argentinean-Chilean collaboration

    NASA Astrophysics Data System (ADS)

    Papandrea, S.; Jin, Y.; Ristori, P.; Otero, L.; Nishizawa, T.; Mizuno, A.; Sugimoto, N.; Quel, E.

    2016-05-01

    Atmospheric monitoring stations are being developed in Argentina. The most important targets are volcanic ashes, desert aerosols in particular Patagonian dust and biomass burning aerosols. Six stations deployed in the Patagonian Region and Buenos Aires have lidar systems, sun photometers integrated to the AERONET/NASA monitoring network, in situ optical particle analyzers, four solar radiation sensors (pyranometer, UVA, UVB and GUV), and meteorological equipment. The stations are in the main international airports of the Regions (San Carlos de Bariloche, Comodoro Rivadavia, Neuquén, Rio Gallegos) and in Buenos Aires (Aeroparque Jorge Newbery and at CEILAP/CITEDEF). CEILAP and the National Institute of Environmental Studies (NIES) at Tsukuba, Japan developed the first iodine cell-based high spectral resolution lidar (HSRL) in Argentina to add in the lidar network. We upgraded the standard CEILAP multi-wavelength Raman lidar adding the laser frequency tuning system and the 532 iodine-filtered channel at the reception to built the HSRL. HSRL will provide daytime and nighttime direct observation of the aerosol and cloud optical properties (backscatter and extinction) without the pre-assumption of the lidar ratio. This work shows the design and construction of the first Argentinean HSRL. We also show the first lidar observations done in the country with this kind of lidar.

  14. Woven heat exchanger

    DOEpatents

    Piscitella, Roger R.

    1987-05-05

    In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  15. Woven heat exchanger

    DOEpatents

    Piscitella, Roger R.

    1987-01-01

    In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  16. 17 CFR 38.157 - Real-time market monitoring.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 1 2014-04-01 2014-04-01 false Real-time market monitoring... DESIGNATED CONTRACT MARKETS Compliance With Rules § 38.157 Real-time market monitoring. A designated contract market must conduct real-time market monitoring of all trading activity on its electronic...

  17. 17 CFR 38.157 - Real-time market monitoring.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 17 Commodity and Securities Exchanges 1 2013-04-01 2013-04-01 false Real-time market monitoring... DESIGNATED CONTRACT MARKETS Compliance With Rules § 38.157 Real-time market monitoring. A designated contract market must conduct real-time market monitoring of all trading activity on its electronic...

  18. Woven heat exchanger

    DOEpatents

    Piscitella, R.R.

    1984-07-16

    This invention relates to a heat exchanger for waste heat recovery from high temperature industrial exhaust streams. In a woven ceramic heat exchanger using the basic tube-in-shell design, each heat exchanger consisting of tube sheets and tube, is woven separately. Individual heat exchangers are assembled in cross-flow configuration. Each heat exchanger is woven from high temperature ceramic fiber, the warp is continuous from tube to tube sheet providing a smooth transition and unitized construction.

  19. Development and application of a low-cost, portable DOAS system for stratospheric composition monitoring over the Argentinean Patagonia and Antarctic stations.

    NASA Astrophysics Data System (ADS)

    Raponi, Marcelo; Jiménez, Rodrigo; Ristori, Pablo; Wolfram, Elian; Tocho, Jorge; Quel, Eduardo

    2010-05-01

    A significant fraction of the Argentinean population is seasonally exposed to elevated UV radiation, particularly during severe stratospheric ozone destruction episodes in Antarctica. In order to provide early alert, global monitoring and to improve our understanding of these phenomena, various Argentinean and international organizations maintain stratospheric composition remote sensing sites from the southern tip of Argentina (Patagonia) to Antarctica. The understating of the ozone destruction dynamics will be significantly improved if more sites were available. For instance, the Laser and Applications Research Center, CEILAP (CITEFA-CONICET, Argentina) carries out systematic measurements of stratospheric ozone and tropospheric water vapor profiles at Rio Gallego (51° 36' S, 69° 19' W, 15 m asl) by means of LIDAR systems. Besides the active systems, the site possesses different passive instruments (GUV-541, UV-B and UV-A radiometers, SAOZ spectrometer, CIMEL sunphotometer) all of them working in synergy. The goal of this work is to present the design and development of a new compact atmospheric remote sensing system, able to determine the vertical column concentration in column (VCD) of multiple trace gases. We have developed a low-cost, portable passive DOAS system, ERO-DOAS, wich circumvents the cost limitations associated with new fixed monitoring sites. It is composed of commercial spectrophotometer (HR4000, Ocean Optics), a 400-μm core, 6-m long optic fiber, and a home-made automatic external shutter. We have developed a LabVIEW® based software for spectrometer/shutter control and data acquisition, and a MATLAB® based software for spectral data reduction. In the work we highlight the main characteristics of the system's components and we describe the visual interface implemented to controls the operation of the whole system, and the calculation algorithms to process the measured zenithal spectra, postulating the strategies implemented to solve the

  20. Evaluation of the biofilm forming ability and its associated genes in Staphylococcus species isolates from bovine mastitis in Argentinean dairy farms.

    PubMed

    Felipe, Verónica; Morgante, Carolina A; Somale, Paola S; Varroni, Florencia; Zingaretti, María L; Bachetti, Romina A; Correa, Silvia G; Porporatto, Carina

    2017-03-01

    Staphylococcus aureus and coagulase-negative staphylococci (CNS) are important causes of intramammary infection in dairy cattle, and their ability to produce biofilm is considered an important virulence property in the pathogenesis of mastitis. However, the published date on mechanisms and factors involved in infection persistence in the mammary gland remains unclear. The aim of this study was to investigate whether the main Staphylococcus species involved in bovine intramammary infections possess specific characteristics that promote colonization of the udder. We evaluated the biofilm-forming ability and distribution of adhesion- and biofilm-associated genes of Staphylococcus spp. isolated from bovine mastitis infected animals in Argentinean dairy farms. For this purpose, the phenotypic biofilm formation ability of 209 Staphylococcus spp. from bovine mastitis was investigated. All isolates produced biofilm in vitro, being 35,0% and 45,0% of the 127 S. aureus or 51,0% and 29,0% of the 82 CNS strong and moderate biofilm producers respectively. All S. aureus samples were PCR-positive for icaA, icaD, clfA, clfB and fnbpA genes, 76.3% were positive for fnbpB gene and 11.0% were positive for bap gene. In CNS isolates, the positive rates for icaA and icaD were 73.2%, while for clfA, clfB, fnbpA fnbpB and bap genes the percentage were lower. The results demonstrate that in Staphylococcus spp. biofilm formation, the polysaccharide and the adhesion- and biofilm-associated genes are of overall importance on bovine mastitis in Argentina. Therefore, future works should focus on these pathogenic specific factors for the development of more effective therapies of control, being essential to consider the ability of isolates to produce biofilm.

  1. The discovery of stromatolites developing at 3570 m above sea level in a high-altitude volcanic lake Socompa, Argentinean Andes.

    PubMed

    Farías, María E; Rascovan, Nicolás; Toneatti, Diego M; Albarracín, Virginia H; Flores, María R; Poiré, Daniel G; Collavino, Mónica M; Aguilar, O Mario; Vazquez, Martin P; Polerecky, Lubos

    2013-01-01

    We describe stromatolites forming at an altitude of 3570 m at the shore of a volcanic lake Socompa, Argentinean Andes. The water at the site of stromatolites formation is alkaline, hypersaline, rich in inorganic nutrients, very rich in arsenic, and warm (20-24°C) due to a hydrothermal input. The stromatolites do not lithify, but form broad, rounded and low-domed bioherms dominated by diatom frustules and aragonite micro-crystals agglutinated by extracellular substances. In comparison to other modern stromatolites, they harbour an atypical microbial community characterized by highly abundant representatives of Deinococcus-Thermus, Rhodobacteraceae, Desulfobacterales and Spirochaetes. Additionally, a high proportion of the sequences that could not be classified at phylum level showed less than 80% identity to the best hit in the NCBI database, suggesting the presence of novel distant lineages. The primary production in the stromatolites is generally high and likely dominated by Microcoleus sp. Through negative phototaxis, the location of these cyanobacteria in the stromatolites is controlled by UV light, which greatly influences their photosynthetic activity. Diatoms, dominated by Amphora sp., are abundant in the anoxic, sulfidic and essentially dark parts of the stromatolites. Although their origin in the stromatolites is unclear, they are possibly an important source of anaerobically degraded organic matter that induces in situ aragonite precipitation. To the best of our knowledge, this is so far the highest altitude with documented actively forming stromatolites. Their generally rich, diverse and to a large extent novel microbial community likely harbours valuable genetic and proteomic reserves, and thus deserves active protection. Furthermore, since the stromatolites flourish in an environment characterized by a multitude of extremes, including high exposure to UV radiation, they can be an excellent model system for studying microbial adaptations under

  2. The Discovery of Stromatolites Developing at 3570 m above Sea Level in a High-Altitude Volcanic Lake Socompa, Argentinean Andes

    PubMed Central

    Farías, María E.; Rascovan, Nicolás; Toneatti, Diego M.; Albarracín, Virginia H.; Flores, María R.; Poiré, Daniel G.; Collavino, Mónica M.; Aguilar, O. Mario; Vazquez, Martin P.; Polerecky, Lubos

    2013-01-01

    We describe stromatolites forming at an altitude of 3570 m at the shore of a volcanic lake Socompa, Argentinean Andes. The water at the site of stromatolites formation is alkaline, hypersaline, rich in inorganic nutrients, very rich in arsenic, and warm (20–24°C) due to a hydrothermal input. The stromatolites do not lithify, but form broad, rounded and low-domed bioherms dominated by diatom frustules and aragonite micro-crystals agglutinated by extracellular substances. In comparison to other modern stromatolites, they harbour an atypical microbial community characterized by highly abundant representatives of Deinococcus-Thermus, Rhodobacteraceae, Desulfobacterales and Spirochaetes. Additionally, a high proportion of the sequences that could not be classified at phylum level showed less than 80% identity to the best hit in the NCBI database, suggesting the presence of novel distant lineages. The primary production in the stromatolites is generally high and likely dominated by Microcoleus sp. Through negative phototaxis, the location of these cyanobacteria in the stromatolites is controlled by UV light, which greatly influences their photosynthetic activity. Diatoms, dominated by Amphora sp., are abundant in the anoxic, sulfidic and essentially dark parts of the stromatolites. Although their origin in the stromatolites is unclear, they are possibly an important source of anaerobically degraded organic matter that induces in situ aragonite precipitation. To the best of our knowledge, this is so far the highest altitude with documented actively forming stromatolites. Their generally rich, diverse and to a large extent novel microbial community likely harbours valuable genetic and proteomic reserves, and thus deserves active protection. Furthermore, since the stromatolites flourish in an environment characterized by a multitude of extremes, including high exposure to UV radiation, they can be an excellent model system for studying microbial adaptations under

  3. In vitro growth and cell wall degrading enzyme production by Argentinean isolates of Macrophomina phaseolina, the causative agent of charcoal rot in corn.

    PubMed

    Ramos, Araceli M; Gally, Marcela; Szapiro, Gala; Itzcovich, Tatiana; Carabajal, Maira; Levin, Laura

    Macrophomina phaseolina is a polyphagous phytopathogen, causing stalk rot on many commercially important species. Damages caused by this pathogen in soybean and maize crops in Argentina during drought and hot weather have increased due its ability to survive as sclerotia in soil and crop debris under non-till practices. In this work, we explored the in vitro production of plant cell wall-degrading enzymes [pectinases (polygalacturonase and polymethylgalacturonase); cellulases (endoglucanase); hemicellulases (endoxylanase) and the ligninolytic enzyme laccase] by several Argentinean isolates of M. phaseolina, and assessed the pathogenicity of these isolates as a preliminary step to establish the role of these enzymes in M. phaseolina-maize interaction. The isolates were grown in liquid synthetic medium supplemented with glucose, pectin, carboxymethylcellulose or xylan as carbon sources and/or enzyme inducers and glutamic acid as nitrogen source. Pectinases were the first cell wall-degrading enzymes detected and the activities obtained (polygalacturonase activity was between 0.4 and 1.3U/ml and polymethylgalacturonase between 0.15 and 1.3U/ml) were higher than those of cellulases and xylanases, which appeared later and in a lesser magnitude. This sequence would promote initial tissue maceration followed by cell wall degradation. Laccase was detected in all the isolates evaluated (activity was between 36U/l and 63U/l). The aggressiveness of the isolates was tested in maize, sunflower and watermelon seeds, being high on all the plants assayed. This study reports for the first time the potential of different isolates of M. phaseolina to produce plant cell wall-degrading enzymes in submerged fermentation.

  4. Indiana Health Information Exchange

    Cancer.gov

    The Indiana Health Information Exchange is comprised of various Indiana health care institutions, established to help improve patient safety and is recognized as a best practice for health information exchange.

  5. Charge exchange system

    DOEpatents

    Anderson, Oscar A.

    1978-01-01

    An improved charge exchange system for substantially reducing pumping requirements of excess gas in a controlled thermonuclear reactor high energy neutral beam injector. The charge exchange system utilizes a jet-type blanket which acts simultaneously as the charge exchange medium and as a shield for reflecting excess gas.

  6. Photocopy of photograph in the Fitzsimons Army Medical Center Real ...

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

    Photocopy of photograph in the Fitzsimons Army Medical Center Real Property Book (green cloth cover). - Fitzsimons General Hospital, Post Exchange Garage, Northwest Corner of West Pennington Avenue & North Eighth Street, Aurora, Adams County, CO

  7. Photocopy of photograph in the Fitzsimons Army Medical Center Real ...

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

    Photocopy of photograph in the Fitzsimons Army Medical Center Real Property Book (green cloth cover), south and east sides. - Fitzsimons General Hospital, Post Exchange Garage, North Eighth Street, North of Building No. 143, Aurora, Adams County, CO

  8. 76 FR 56832 - Self-Regulatory Organizations; International Securities Exchange, LLC; Notice of Filing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-14

    ... (the ``Exchange'' or the ``ISE'') filed with the Securities and Exchange Commission (``Commission... data offering called the ISE Real-time Implied Volatilities and Greeks Feed. The proposed rule change is available on the Exchange's Web site http://www.ise.com , at the principal office of the...

  9. 17 CFR 210.12-24 - Real estate owned and rental income. 1

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Real estate owned and rental... § 210.12-24 Real estate owned and rental income. 1 Part 1—Real estate owned at end of period Column A... In a separate schedule classify by states in which the real estate owned is located the total...

  10. Nonsurvivable momentum exchange system

    NASA Technical Reports Server (NTRS)

    Roder, Russell (Inventor); Ahronovich, Eliezer (Inventor); Davis, III, Milton C. (Inventor)

    2007-01-01

    A demiseable momentum exchange system includes a base and a flywheel rotatably supported on the base. The flywheel includes a web portion defining a plurality of web openings and a rim portion. The momentum exchange system further includes a motor for driving the flywheel and a cover for engaging the base to substantially enclose the flywheel. The system may also include components having a melting temperature below 1500 degrees Celsius. The momentum exchange system is configured to demise on reentry.

  11. Text Exchange System

    NASA Technical Reports Server (NTRS)

    Snyder, W. V.; Hanson, R. J.

    1986-01-01

    Text Exchange System (TES) exchanges and maintains organized textual information including source code, documentation, data, and listings. System consists of two computer programs and definition of format for information storage. Comprehensive program used to create, read, and maintain TES files. TES developed to meet three goals: First, easy and efficient exchange of programs and other textual data between similar and dissimilar computer systems via magnetic tape. Second, provide transportable management system for textual information. Third, provide common user interface, over wide variety of computing systems, for all activities associated with text exchange.

  12. 17 CFR 210.3-14 - Special instructions for real estate operations to be acquired.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... General Instructions As to Financial Statements § 210.3-14 Special instructions for real estate operations... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Special instructions for real estate operations to be acquired. 210.3-14 Section 210.3-14 Commodity and Securities Exchanges...

  13. 17 CFR 210.8-06 - Real estate operations acquired or to be acquired.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Real estate operations acquired or to be acquired. 210.8-06 Section 210.8-06 Commodity and Securities Exchanges SECURITIES AND... Statements of Smaller Reporting Companies § 210.8-06 Real estate operations acquired or to be acquired....

  14. 17 CFR 210.3-15 - Special provisions as to real estate investment trusts.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Financial Statements § 210.3-15 Special provisions as to real estate investment trusts. (a)(1) The income... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Special provisions as to real... EXCHANGE COMMISSION FORM AND CONTENT OF AND REQUIREMENTS FOR FINANCIAL STATEMENTS, SECURITIES ACT OF...

  15. Aharonov-Casher effect in exchange interactions in a Wigner crystal.

    PubMed

    Tserkovnyak, Yaroslav; Kindermann, Markus

    2009-03-27

    We theoretically study the effects of spin-orbit coupling on spin exchange in a low-density Wigner crystal. In addition to the familiar antiferromagnetic Heisenberg exchange, we find general anisotropic interactions in spin space if the exchange paths allowed by the crystal structure form loops in real space. In particular, it is shown that the two-electron exchange interaction can acquire ferromagnetic character.

  16. Price of Fairness in Kidney Exchange

    DTIC Science & Technology

    2014-05-01

    patients in need of a new kidney. Fielded exchanges typi- cally match under utilitarian or near- utilitarian rules; this approach marginalizes certain...empirically explore the tradeoff between matching more hard-to- match patients and the overall utility of a utilitarian matching, on real data from the UNOS...under utilitarian or near- utilitarian rules; this approach marginalizes certain classes of patients. In this paper, we focus on improving access to

  17. Higher Education Exchange, 2012

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2012-01-01

    "Higher Education Exchange" publishes case studies, analyses, news, and ideas about efforts within higher education to develop more democratic societies. Contributors to this issue of the "Higher Education Exchange" examine whether institutions of higher learning are doing anything to increase the capacity of citizens to shape…

  18. Higher Education Exchange, 2004

    ERIC Educational Resources Information Center

    Brown, David W., Ed; Witte, Deborah, Ed.

    2004-01-01

    The Higher Education Exchange is part of a movement to strengthen higher education's democratic mission and foster a more democratic culture throughout American society. Working in this tradition, the Higher Education Exchange publishes case studies, analyses, news, and ideas about efforts within higher education to develop more democratic…

  19. Direct fired heat exchanger

    DOEpatents

    Reimann, Robert C.; Root, Richard A.

    1986-01-01

    A gas-to-liquid heat exchanger system which transfers heat from a gas, generally the combustion gas of a direct-fired generator of an absorption machine, to a liquid, generally an absorbent solution. The heat exchanger system is in a counterflow fluid arrangement which creates a more efficient heat transfer.

  20. Higher Education Exchange, 2011

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2011-01-01

    "Higher Education Exchange" publishes case studies, analyses, news, and ideas about efforts within higher education to develop more democratic societies. Contributors to this issue of the "Higher Education Exchange" examine whether institutions of higher learning are doing anything to increase the capacity of citizens to shape…

  1. Optimization of Heat Exchangers

    SciTech Connect

    Ivan Catton

    2010-10-01

    The objective of this research is to develop tools to design and optimize heat exchangers (HE) and compact heat exchangers (CHE) for intermediate loop heat transport systems found in the very high temperature reator (VHTR) and other Generation IV designs by addressing heat transfer surface augmentation and conjugate modeling. To optimize heat exchanger, a fast running model must be created that will allow for multiple designs to be compared quickly. To model a heat exchanger, volume averaging theory, VAT, is used. VAT allows for the conservation of mass, momentum and energy to be solved for point by point in a 3 dimensional computer model of a heat exchanger. The end product of this project is a computer code that can predict an optimal configuration for a heat exchanger given only a few constraints (input fluids, size, cost, etc.). As VAT computer code can be used to model characteristics )pumping power, temperatures, and cost) of heat exchangers more quickly than traditional CFD or experiment, optimization of every geometric parameter simultaneously can be made. Using design of experiment, DOE and genetric algorithms, GE, to optimize the results of the computer code will improve heat exchanger disign.

  2. Higher Education Exchange, 2010

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2010-01-01

    "Higher Education Exchange" publishes case studies, analyses, news, and ideas about efforts within higher education to develop more democratic societies. Contributors to this issue of the "Higher Education Exchange" examine whether institutions of higher learning are doing anything to increase the capacity of citizens to shape their future.…

  3. Higher Education Exchange, 2008

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2008-01-01

    "Higher Education Exchange" publishes case studies, analyses, news, and ideas about efforts within higher education to develop more democratic societies. Contributors to this issue of the "Higher Education Exchange" examine whether institutions of higher learning are doing anything to increase the capacity of citizens to shape…

  4. Building Relationships through Exchange

    ERIC Educational Resources Information Center

    Primavera, Angi; Hall, Ellen

    2011-01-01

    From the moment of birth, children form and develop relationships with others in their world based on exchange. Children recognize that engaging in such encounters offers them the opportunity to enter into a relationship with another individual and to nurture that relationship through the exchange of messages and gifts, items and ideas. At Boulder…

  5. Handicapping Social Exchange Theory.

    ERIC Educational Resources Information Center

    Mishler, Barbara

    The economic theory of social exchange has some serious shortcomings when applied to minorities--especially the disabled. First, it assumes dyads comprise the basic unit where exchange occurs and that rewards and costs must occur at that level. Second, the model standardizes the experience of white, Western European and American males. The model…

  6. Initial validation of the Argentinean Spanish version of the PedsQL™ 4.0 Generic Core Scales in children and adolescents with chronic diseases: acceptability and comprehensibility in low-income settings

    PubMed Central

    Roizen, Mariana; Rodríguez, Susana; Bauer, Gabriela; Medin, Gabriela; Bevilacqua, Silvina; Varni, James W; Dussel, Veronica

    2008-01-01

    Background To validate the Argentinean Spanish version of the PedsQL™ 4.0 Generic Core Scales in Argentinean children and adolescents with chronic conditions and to assess the impact of socio-demographic characteristics on the instrument's comprehensibility and acceptability. Reliability, and known-groups, and convergent validity were tested. Methods Consecutive sample of 287 children with chronic conditions and 105 healthy children, ages 2–18, and their parents. Chronically ill children were: (1) attending outpatient clinics and (2) had one of the following diagnoses: stem cell transplant, chronic obstructive pulmonary disease, HIV/AIDS, cancer, end stage renal disease, complex congenital cardiopathy. Patients and adult proxies completed the PedsQL™ 4.0 and an overall health status assessment. Physicians were asked to rate degree of health status impairment. Results The PedsQL™ 4.0 was feasible (only 9 children, all 5 to 7 year-olds, could not complete the instrument), easy to administer, completed without, or with minimal, help by most children and parents, and required a brief administration time (average 5–6 minutes). People living below the poverty line and/or low literacy needed more help to complete the instrument. Cronbach Alpha's internal consistency values for the total and subscale scores exceeded 0.70 for self-reports of children over 8 years-old and parent-reports of children over 5 years of age. Reliability of proxy-reports of 2–4 year-olds was low but improved when school items were excluded. Internal consistency for 5–7 year-olds was low (α range = 0.28–0.76). Construct validity was good. Child self-report and parent proxy-report PedsQL™ 4.0 scores were moderately but significantly correlated (ρ = 0.39, p < 0.0001) and both significantly correlated with physician's assessment of health impairment and with child self-reported overall health status. The PedsQL™ 4.0 discriminated between healthy and chronically ill children (72

  7. Spread of Epidemic MRSA-ST5-IV Clone Encoding PVL as a Major Cause of Community Onset Staphylococcal Infections in Argentinean Children

    PubMed Central

    Sola, Claudia; Egea, Ana L.; Moyano, Alejandro J.; Garnero, Analia; Kevric, Ines; Culasso, Catalina; Vindel, Ana; Lopardo, Horacio; Bocco, José L.

    2012-01-01

    and was associated with a SCCmec type closely related to SCCmecIV(2B&5). Conclusions/Significance The dissemination of epidemic MRSA clone, ST5-IV-PVL+ was the main cause of increasing staphylococcal community-onset infections in Argentinean children (2003–2008), conversely to other countries. The predominance of this clone, which has capacity to express the h-VISA phenotype, in healthcare-associated community-onset cases suggests that it has infiltrated into hospital-settings. PMID:22291965

  8. 4G/5G plasminogen activator inhibitor-1 and -308 A/G tumor necrosis factor-α promoter gene polymorphisms in Argentinean lupus patients: focus on lupus nephritis.

    PubMed

    Muñoz, Sebastián Andrés; Aranda, Federico; Allievi, Alberto; Orden, Alberto Omar; Perés Wingeyer, Silvia; Trobo, Rosana; Alvarez, Analía; Eimon, Alicia; Barreira, Juan Carlos; Schneeberger, Emilce; Dal Pra, Fernando; Sarano, Judith; Hofman, Julio; Chamorro, Julián; de Larrañaga, Gabriela

    2014-02-01

    We investigated the relationship between the 4G/5G plasminogen activator inhibitor (PAI-1) and -308 A/G tumor necrosis factor-α (TNF-α) polymorphisms and the clinical and biochemical features of systemic lupus erythematosus (SLE) in an Argentinean patient cohort. A total of 402 patients were studied, including 179 SLE patients and 223 healthy individuals. PCR-RLFP was used to determine the genotypes of the 4G/5G PAI-1 and -308 A/G TNF-α polymorphisms. SLE patients with lupus nephritis (LN) (n = 86) were compared with patients without LN (n = 93). Additionally, LN patients were divided into proliferative LN and non-proliferative LN groups according to the results of the renal biopsies. No significant differences were noted in the genotype distributions or allele frequencies of these TNF-α and PAI-1 polymorphisms between SLE patients and controls. There were higher numbers of criteria for SLE, more lupus flares and higher damage scores in LN patients, but there were similar frequencies of anti-phospholipid antibody (APA) positivity and anti-phospholipid syndrome. No significant difference was noted for any studied variable between the proliferative LN and non-proliferative LN groups except for the presence of APA. We found no significant differences in the TNF-α and PAI-1 genotype distributions or allele frequencies between groups. We found that the -308 A/G TNF-α and 4G/5G PAI-1 polymorphisms are not associated with susceptibility to SLE in an Argentinean population. We also did not find any association between the presence of any specific allele or genotype and the development of LN in SLE patients. Finally, no association was noted between either of the two polymorphisms and the severity of renal disease.

  9. Anion exchange membrane

    DOEpatents

    Verkade, John G; Wadhwa, Kuldeep; Kong, Xueqian; Schmidt-Rohr, Klaus

    2013-05-07

    An anion exchange membrane and fuel cell incorporating the anion exchange membrane are detailed in which proazaphosphatrane and azaphosphatrane cations are covalently bonded to a sulfonated fluoropolymer support along with anionic counterions. A positive charge is dispersed in the aforementioned cations which are buried in the support to reduce the cation-anion interactions and increase the mobility of hydroxide ions, for example, across the membrane. The anion exchange membrane has the ability to operate at high temperatures and in highly alkaline environments with high conductivity and low resistance.

  10. Wound tube heat exchanger

    DOEpatents

    Ecker, Amir L.

    1983-01-01

    What is disclosed is a wound tube heat exchanger in which a plurality of tubes having flattened areas are held contiguous adjacent flattened areas of tubes by a plurality of windings to give a double walled heat exchanger. The plurality of windings serve as a plurality of effective force vectors holding the conduits contiguous heat conducting walls of another conduit and result in highly efficient heat transfer. The resulting heat exchange bundle is economical and can be coiled into the desired shape. Also disclosed are specific embodiments such as the one in which the tubes are expanded against their windings after being coiled to insure highly efficient heat transfer.

  11. Cryptographic Securities Exchanges

    NASA Astrophysics Data System (ADS)

    Thorpe, Christopher; Parkes, David C.

    While transparency in financial markets should enhance liquidity, its exploitation by unethical and parasitic traders discourages others from fully embracing disclosure of their own information. Traders exploit both the private information in upstairs markets used to trade large orders outside traditional exchanges and the public information present in exchanges' quoted limit order books. Using homomorphic cryptographic protocols, market designers can create "partially transparent" markets in which every matched trade is provably correct and only beneficial information is revealed. In a cryptographic securities exchange, market operators can hide information to prevent its exploitation, and still prove facts about the hidden information such as bid/ask spread or market depth.

  12. Active microchannel heat exchanger

    DOEpatents

    Tonkovich, Anna Lee Y [Pasco, WA; Roberts, Gary L [West Richland, WA; Call, Charles J [Pasco, WA; Wegeng, Robert S [Richland, WA; Wang, Yong [Richland, WA

    2001-01-01

    The present invention is an active microchannel heat exchanger with an active heat source and with microchannel architecture. The microchannel heat exchanger has (a) an exothermic reaction chamber; (b) an exhaust chamber; and (c) a heat exchanger chamber in thermal contact with the exhaust chamber, wherein (d) heat from the exothermic reaction chamber is convected by an exothermic reaction exhaust through the exhaust chamber and by conduction through a containment wall to the working fluid in the heat exchanger chamber thereby raising a temperature of the working fluid. The invention is particularly useful as a liquid fuel vaporizer and/or a steam generator for fuel cell power systems, and as a heat source for sustaining endothermic chemical reactions and initiating exothermic reactions.

  13. Compact, super heat exchanger

    NASA Technical Reports Server (NTRS)

    Fortini, A.; Kazaroff, J. M.

    1980-01-01

    Heat exchanger uses porous media to enhance heat transfer through walls of cooling channels, thereby lowering wall temperature. Porous media within cooling channel increases internal surface area from which heat can be transferred to coolant. Comparison data shows wall has lower temperature and coolant has higher temperature when porous medium is used within heat exchanger. Media can be sintered powedered metal, metal fibers, woven wire layers, or any porous metal having desired permeability and porosity.

  14. Hibernation and gas exchange.

    PubMed

    Milsom, William K; Jackson, Donald C

    2011-01-01

    Hibernation in endotherms and ectotherms is characterized by an energy-conserving metabolic depression due to low body temperatures and poorly understood temperature-independent mechanisms. Rates of gas exchange are correspondly reduced. In hibernating mammals, ventilation falls even more than metabolic rate leading to a relative respiratory acidosis that may contribute to metabolic depression. Breathing in some mammals becomes episodic and in some small mammals significant apneic gas exchange may occur by passive diffusion via airways or skin. In ectothermic vertebrates, extrapulmonary gas exchange predominates and in reptiles and amphibians hibernating underwater accounts for all gas exchange. In aerated water diffusive exchange permits amphibians and many species of turtles to remain fully aerobic, but hypoxic conditions can challenge many of these animals. Oxygen uptake into blood in both endotherms and ectotherms is enhanced by increased affinity of hemoglobin for O₂ at low temperature. Regulation of gas exchange in hibernating mammals is predominately linked to CO₂/pH, and in episodic breathers, control is principally directed at the duration of the apneic period. Control in submerged hibernating ectotherms is poorly understood, although skin-diffusing capacity may increase under hypoxic conditions. In aerated water blood pH of frogs and turtles either adheres to alphastat regulation (pH ∼8.0) or may even exhibit respiratory alkalosis. Arousal in hibernating mammals leads to restoration of euthermic temperature, metabolic rate, and gas exchange and occurs periodically even as ambient temperatures remain low, whereas body temperature, metabolic rate, and gas exchange of hibernating ectotherms are tightly linked to ambient temperature.

  15. Microtube strip heat exchanger

    SciTech Connect

    Doty, F.D.

    1992-07-09

    The purpose of this contract has been to explore the limits of miniaturization of heat exchangers with the goals of (1) improving the theoretical understanding of laminar heat exchangers, (2) evaluating various manufacturing difficulties, and (3) identifying major applications for the technology. A low-cost, ultra-compact heat exchanger could have an enormous impact on industry in the areas of cryocoolers and energy conversion. Compact cryocoolers based on the reverse Brayton cycle (RBC) would become practical with the availability of compact heat exchangers. Many experts believe that hardware advances in personal computer technology will rapidly slow down in four to six years unless lowcost, portable cryocoolers suitable for the desktop supercomputer can be developed. Compact refrigeration systems would permit dramatic advances in high-performance computer work stations with conventional'' microprocessors operating at 150 K, and especially with low-cost cryocoolers below 77 K. NASA has also expressed strong interest in our MTS exchanger for space-based RBC cryocoolers for sensor cooling. We have demonstrated feasibility of higher specific conductance by a factor of five than any other work in high-temperature gas-to-gas exchangers. These laminar-flow, microtube exchangers exhibit extremely low pressure drop compared to alternative compact designs under similar conditions because of their much shorter flow length and larger total flow area for lower flow velocities. The design appears to be amenable to mass production techniques, but considerable process development remains. The reduction in materials usage and the improved heat exchanger performance promise to be of enormous significance in advanced engine designs and in cryogenics.

  16. Cryptographic Combinatorial Securities Exchanges

    NASA Astrophysics Data System (ADS)

    Thorpe, Christopher; Parkes, David C.

    We present a useful new mechanism that facilitates the atomic exchange of many large baskets of securities in a combinatorial exchange. Cryptography prevents information about the securities in the baskets from being exploited, enhancing trust. Our exchange offers institutions who wish to trade large positions a new alternative to existing methods of block trading: they can reduce transaction costs by taking advantage of other institutions’ available liquidity, while third party liquidity providers guarantee execution—preserving their desired portfolio composition at all times. In our exchange, institutions submit encrypted orders which are crossed, leaving a “remainder”. The exchange proves facts about the portfolio risk of this remainder to third party liquidity providers without revealing the securities in the remainder, the knowledge of which could also be exploited. The third parties learn either (depending on the setting) the portfolio risk parameters of the remainder itself, or how their own portfolio risk would change if they were to incorporate the remainder into a portfolio they submit. In one setting, these third parties submit bids on the commission, and the winner supplies necessary liquidity for the entire exchange to clear. This guaranteed clearing, coupled with external price discovery from the primary markets for the securities, sidesteps difficult combinatorial optimization problems. This latter method of proving how taking on the remainder would change risk parameters of one’s own portfolio, without revealing the remainder’s contents or its own risk parameters, is a useful protocol of independent interest.

  17. Vacuum powered heat exchanger

    SciTech Connect

    Ruffolo, R.F.

    1986-06-24

    In an internal combustion engine including an oil lubrication system, a liquid cooling system, and an improved air intake system is described. The improved air intake system comprises: a housing including a first opening in one end, which opening is open to the atmosphere and a second opening comprising an air outlet opening in the other end open to the air intake manifold of the engine, a heat exchanger positioned in the first opening. The heat exchanger consists of a series of coils positioned in the flow path of the atmospheric air as it enters the housing, the heat exchanger being fluidly connected to either the engine lubrication system or the cooling system to provide a warm heat source for the incoming air to the housing, acceleration means positioned in the housing downstream of the heat exchanger, the acceleration means comprising a honeycomb structure positioned across the air intake flow path. The honey-comb structure includes a multitude of honey combed mini-venturi cells through which the heated air flows in an accelerated mode, a removable air filter positioned between the heat exchanger and the acceleration means and a single opening provided in the housing through which the air filter can be passed and removed, and additional openings in the housing positioned downstream of the heat exchanger and upstream of the air filter, the additional openings including removable flaps for opening and closing the openings to control the temperature of the air flowing through the housing.

  18. 17 CFR 210.12-28 - Real estate and accumulated depreciation. 1

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Real estate and accumulated... § 210.12-28 Real estate and accumulated depreciation. 1 Column A—Description 2 Column B—Encumbrances... which real estate was carried at the beginning of each period for which income statements are...

  19. 17 CFR 210.12-29 - Mortgage loans on real estate. 1

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Mortgage loans on real estate... § 210.12-29 Mortgage loans on real estate. 1 Column A—Description 2,3,4 Column B—Interest rate Column C... mortgage loans on real estate investments has been written down or reserved against, describe the item...

  20. Performance bound for real OTEC heat engines

    SciTech Connect

    Wu, C.

    1987-01-01

    Maximum power and efficiency at the maximum power of an irreversible OTEC heat engine are treated. When time is explicitly considered in the energy exchanges between the heat engine and its surroundings, it is found that there is a bound on the efficiency of the real OTEC heat engine at the maximum power condition. This bound can guide the evaluation of existing OTEC systems or influence design of future OTEC heat engines.

  1. Microgravity condensing heat exchanger

    NASA Technical Reports Server (NTRS)

    Thomas, Christopher M. (Inventor); Ma, Yonghui (Inventor); North, Andrew (Inventor); Weislogel, Mark M. (Inventor)

    2011-01-01

    A heat exchanger having a plurality of heat exchanging aluminum fins with hydrophilic condensing surfaces which are stacked and clamped between two cold plates. The cold plates are aligned radially along a plane extending through the axis of a cylindrical duct and hold the stacked and clamped portions of the heat exchanging fins along the axis of the cylindrical duct. The fins extend outwardly from the clamped portions along approximately radial planes. The spacing between fins is symmetric about the cold plates, and are somewhat more closely spaced as the angle they make with the cold plates approaches 90.degree.. Passageways extend through the fins between vertex spaces which provide capillary storage and communicate with passageways formed in the stacked and clamped portions of the fins, which communicate with water drains connected to a pump externally to the duct. Water with no entrained air is drawn from the capillary spaces.

  2. Ion exchange phenomena

    SciTech Connect

    Bourg, I.C.; Sposito, G.

    2011-05-01

    Ion exchange phenomena involve the population of readily exchangeable ions, the subset of adsorbed solutes that balance the intrinsic surface charge and can be readily replaced by major background electrolyte ions (Sposito, 2008). These phenomena have occupied a central place in soil chemistry research since Way (1850) first showed that potassium uptake by soils resulted in the release of an equal quantity of moles of charge of calcium and magnesium. Ion exchange phenomena are now routinely modeled in studies of soil formation (White et al., 2005), soil reclamation (Kopittke et al., 2006), soil fertilitization (Agbenin and Yakubu, 2006), colloidal dispersion/flocculation (Charlet and Tournassat, 2005), the mechanics of argillaceous media (Gajo and Loret, 2007), aquitard pore water chemistry (Tournassat et al., 2008), and groundwater (Timms and Hendry, 2007; McNab et al., 2009) and contaminant hydrology (Chatterjee et al., 2008; van Oploo et al., 2008; Serrano et al., 2009).

  3. Heat exchanger panel

    NASA Technical Reports Server (NTRS)

    Warburton, Robert E. (Inventor); Cuva, William J. (Inventor)

    2005-01-01

    The present invention relates to a heat exchanger panel which has broad utility in high temperature environments. The heat exchanger panel has a first panel, a second panel, and at least one fluid containment device positioned intermediate the first and second panels. At least one of the first panel and the second panel have at least one feature on an interior surface to accommodate the at least one fluid containment device. In a preferred embodiment, each of the first and second panels is formed from a high conductivity, high temperature composite material. Also, in a preferred embodiment, the first and second panels are joined together by one or more composite fasteners.

  4. Alert Exchange Process Protocol

    NASA Technical Reports Server (NTRS)

    Groen, Frank

    2015-01-01

    The National Aeronautics and Space Administration of the United States of America (NASA), and the European Space Agency (ESA), and the Japanese Aerospace Exploration Agency (JAXA), acknowledging that NASA, ESA and JAXA have a mutual interest in exchanging Alerts and Alert Status Lists to enhance the information base for each system participant while fortifying the general level of cooperation between the policy agreement subscribers, and each Party will exchange Alert listings on regular basis and detailed Alert information on a need to know basis to the extent permitted by law.

  5. Microscale Regenerative Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Moran, Matthew E.; Stelter, Stephan; Stelter, Manfred

    2006-01-01

    The device described herein is designed primarily for use as a regenerative heat exchanger in a miniature Stirling engine or Stirling-cycle heat pump. A regenerative heat exchanger (sometimes called, simply, a "regenerator" in the Stirling-engine art) is basically a thermal capacitor: Its role in the Stirling cycle is to alternately accept heat from, then deliver heat to, an oscillating flow of a working fluid between compression and expansion volumes, without introducing an excessive pressure drop. These volumes are at different temperatures, and conduction of heat between these volumes is undesirable because it reduces the energy-conversion efficiency of the Stirling cycle.

  6. Currency Exchange Rates.

    ERIC Educational Resources Information Center

    Siler, Carl R.

    This curriculum unit of the Muncie (Indiana) Southside High School is to simulate the dynamics of foreign currency exchange rates from the perspectives of: (1) a major U.S. corporation, ABB Power T & D Company, Inc., of Muncie, Indiana, a manufacturer of large power transformers for the domestic and foreign markets; and (2) individual…

  7. Chimney heat exchanger

    SciTech Connect

    Whiteley, I.C.

    1981-09-01

    A heat exchanger for installation on the top of a chimney of a building includes a housing having a lower end receiving the top of the chimney and an upper end with openings permitting the escape of effluent from the chimney and a heat exchanger assembly disposed in the housing including a central chamber and a spirally arranged duct network defining an effluent spiral path between the top of the chimney and the central chamber and a fresh air spiral path between an inlet disposed at the lower end of the housing and the central chamber, the effluent and fresh air spiral paths being in heat exchange relationship such that air passing through the fresh air spiral path is heated by hot effluent gases passing upward through the chimney and the effluent spiral path for use in heating the building. A pollution trap can be disposed in the central chamber of the heat exchanger assembly for removing pollutants from the effluent, the pollution trap including a rotating cage carrying pumice stones for absorbing pollutants from the effluent with the surface of the pumice gradually ground off to reveal fresh stone as the cage rotates.

  8. Higher Education Exchange, 2014

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2014-01-01

    Research shows that not only does higher education not see the public; when the public, in turn, looks at higher education, it sees mostly malaise, inefficiencies, expense, and unfulfilled promises. Yet, the contributors to this issue of the "Higher Education Exchange" tell of bright spots in higher education where experiments in working…

  9. Technology Performance Exchange

    SciTech Connect

    2015-09-01

    To address the need for accessible, high-quality data, the Department of Energy has developed the Technology Performance Exchange (TPEx). TPEx enables technology suppliers, third-party testing laboratories, and other entities to share product performance data. These data are automatically transformed into a format that technology evaluators can easily use in their energy modeling assessments to inform procurement decisions.

  10. Nature's Heat Exchangers.

    ERIC Educational Resources Information Center

    Barnes, George

    1991-01-01

    Discusses the heat-transfer systems of different animals. Systems include heat conduction into the ground, heat transferred by convection, heat exchange in lizards, fish and polar animals, the carotid rete system, electromagnetic radiation from animals and people, and plant and animal fiber optics. (MDH)

  11. Research Exchange, 2002.

    ERIC Educational Resources Information Center

    Research Exchange, 2002

    2002-01-01

    These three issues of the "Research Exchange" focus on how better to conduct disability research and disseminate research results. The first issue examines the topic of human subject/human research participant protection, with a focus on research funded through the National Institute on Disability and Rehabilitation Research (NIDRR). It…

  12. Visiting Scholar Exchange Reports.

    ERIC Educational Resources Information Center

    Rubin, Kyna, Ed.

    1986-01-01

    Provides reports of four United States scholars who visited China as part of the Visiting Scholar Exchange Program. The titles of the reports are (1) "China Journey: A Political Scientist's Look at Yan'an," (2) "The Social Consequences of Land Reclamation in Chinese Coastal Ecosystems," (3) "Anthropology Lectures in South…

  13. Higher Education Exchange

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2009-01-01

    This volume begins with an essay by Noelle McAfee, a contributor who is familiar to readers of Higher Education Exchange (HEX). She reiterates Mathews' argument regarding the disconnect between higher education's sense of engagement and the public's sense of engagement, and suggests a way around the epistemological conundrum of "knowledge…

  14. Microtube strip heat exchanger

    NASA Astrophysics Data System (ADS)

    Doty, F. D.

    1991-04-01

    During the last quarter, Doty Scientific, Inc. (DSI) continued to make progress on the microtube strip (MTS) heat exchangers. The team has begun a heat exchanger stress analysis; however, they have been concentrating the bulk of their analytical energies on a computational fluid dynmaics (CFD) model to determine the location and magnitude of shell-side flow maldistribution which decreases heat exchanger effectiveness. DSI received 120 fineblanked tubestrips from Southern Fineblanking (SFB) for manufacturing process development. Both SFB and NIST provided inspection reports of the tubestrips. DSI completed the tooling required to encapsulate a tube array and press tubestrips on the array. Pressing the tubestrips on tube arrays showed design deficiencies both in the tubestrip design and the tooling design. DSI has a number of revisions in process to correct these deficiencies. The research effort has identified a more economical fusible alloy for encapsulating the tube array, and determined the parameters required to successfully encapsulate the tube array with the new alloy. A more compact MTS heat exchanger bank was designed.

  15. Higher Education Exchange 2006

    ERIC Educational Resources Information Center

    Brown, David W., Ed.; Witte, Deborah, Ed.

    2006-01-01

    Contributors to this issue of the Higher Education Exchange debate the issues around knowledge production, discuss the acquisition of deliberative skills for democracy, and examine how higher education prepares, or does not prepare, students for citizenship roles. Articles include: (1) "Foreword" (Deborah Witte); (2) "Knowledge,…

  16. Chemical exchange program analysis.

    SciTech Connect

    Waffelaert, Pascale

    2007-09-01

    As part of its EMS, Sandia performs an annual environmental aspects/impacts analysis. The purpose of this analysis is to identify the environmental aspects associated with Sandia's activities, products, and services and the potential environmental impacts associated with those aspects. Division and environmental programs established objectives and targets based on the environmental aspects associated with their operations. In 2007 the most significant aspect identified was Hazardous Materials (Use and Storage). The objective for Hazardous Materials (Use and Storage) was to improve chemical handling, storage, and on-site movement of hazardous materials. One of the targets supporting this objective was to develop an effective chemical exchange program, making a business case for it in FY07, and fully implementing a comprehensive chemical exchange program in FY08. A Chemical Exchange Program (CEP) team was formed to implement this target. The team consists of representatives from the Chemical Information System (CIS), Pollution Prevention (P2), the HWMF, Procurement and the Environmental Management System (EMS). The CEP Team performed benchmarking and conducted a life-cycle analysis of the current management of chemicals at SNL/NM and compared it to Chemical Exchange alternatives. Those alternatives are as follows: (1) Revive the 'Virtual' Chemical Exchange Program; (2) Re-implement a 'Physical' Chemical Exchange Program using a Chemical Information System; and (3) Transition to a Chemical Management Services System. The analysis and benchmarking study shows that the present management of chemicals at SNL/NM is significantly disjointed and a life-cycle or 'Cradle-to-Grave' approach to chemical management is needed. This approach must consider the purchasing and maintenance costs as well as the cost of ultimate disposal of the chemicals and materials. A chemical exchange is needed as a mechanism to re-apply chemicals on site. This will not only reduce the quantity of

  17. Tweeting the Friendly Skies: Investigating Information Exchange among Twitter Users about Airlines

    ERIC Educational Resources Information Center

    Sreenivasan, Nirupama Dharmavaram; Lee, Chei Sian; Goh, Dion Hoe-Lian

    2012-01-01

    Purpose: The purpose of this study is to investigate airline users' microblog postings pertaining to their travel-related information exchange so as to assess their wants, preferences and feedback about airline products and services. Examining such real-time information exchange is important as users rely on this for various purposes such as…

  18. The Effectiveness of Web-Based Foreign Exchange Trading Simulation in an International Finance Course

    ERIC Educational Resources Information Center

    Chou, Chen-Huei; Liu, Hao-Chen

    2013-01-01

    The purpose of this article is to study if trading simulation is an effective tool to increase students' knowledge of the foreign exchange market. We developed a real-time multiuser web-based trading system that replicates an electronic brokerage foreign exchange market. To assess the effectiveness of the program, we conducted surveys in three…

  19. Counterflow Regolith Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Zubrin, Robert; Jonscher, Peter

    2013-01-01

    A problem exists in reducing the total heating power required to extract oxygen from lunar regolith. All such processes require heating a great deal of soil, and the heat energy is wasted if it cannot be recycled from processed material back into new material. The counterflow regolith heat exchanger (CoRHE) is a device that transfers heat from hot regolith to cold regolith. The CoRHE is essentially a tube-in-tube heat exchanger with internal and external augers attached to the inner rotating tube to move the regolith. Hot regolith in the outer tube is moved in one direction by a right-hand - ed auger, and the cool regolith in the inner tube is moved in the opposite direction by a left-handed auger attached to the inside of the rotating tube. In this counterflow arrangement, a large fraction of the heat from the expended regolith is transferred to the new regolith. The spent regolith leaves the heat exchanger close to the temperature of the cold new regolith, and the new regolith is pre-heated close to the initial temperature of the spent regolith. Using the CoRHE can reduce the heating requirement of a lunar ISRU system by 80%, reducing the total power consumption by a factor of two. The unique feature of this system is that it allows for counterflow heat exchange to occur between solids, instead of liquids or gases, as is commonly done. In addition, in variants of this concept, the hydrogen reduction can be made to occur within the counterflow heat exchanger itself, enabling a simplified lunar ISRU (in situ resource utilization) system with excellent energy economy and continuous nonbatch mode operation.

  20. A corrosive resistant heat exchanger

    DOEpatents

    Richlen, S.L.

    1987-08-10

    A corrosive and erosive resistant heat exchanger which recovers heat from a contaminated heat stream. The heat exchanger utilizes a boundary layer of innocuous gas, which is continuously replenished, to protect the heat exchanger surface from the hot contaminated gas. The innocuous gas is pumped through ducts or perforations in the heat exchanger wall. Heat from the heat stream is transferred by radiation to the heat exchanger wall. Heat is removed from the outer heat exchanger wall by a heat recovery medium. 3 figs., 3 tabs.

  1. Magnetic exchange force microscopy with atomic resolution.

    PubMed

    Kaiser, Uwe; Schwarz, Alexander; Wiesendanger, Roland

    2007-03-29

    The ordering of neighbouring atomic magnetic moments (spins) leads to important collective phenomena such as ferromagnetism and antiferromagnetism. A full understanding of magnetism on the nanometre scale therefore calls for information on the arrangement of spins in real space and with atomic resolution. Spin-polarized scanning tunnelling microscopy accomplishes this but can probe only conducting materials. Force microscopy can be used on any sample independent of its conductivity. In particular, magnetic force microscopy is well suited to exploring ferromagnetic domain structures. However, atomic resolution cannot be achieved because data acquisition involves the sensing of long-range magnetostatic forces between tip and sample. Magnetic exchange force microscopy has been proposed for overcoming this limitation: by using an atomic force microscope with a magnetic tip, it should be possible to detect the short-range magnetic exchange force between tip and sample spins. Here we show for a prototypical antiferromagnetic insulator, the (001) surface of nickel oxide, that magnetic exchange force microscopy can indeed reveal the arrangement of both surface atoms and their spins simultaneously. In contrast with previous attempts to implement this method, we use an external magnetic field to align the magnetic polarization at the tip apex so as to optimize the interaction between tip and sample spins. This allows us to observe the direct magnetic exchange coupling between the spins of the tip atom and sample atom that are closest to each other, and thereby demonstrate the potential of magnetic exchange force microscopy for investigations of inter-spin interactions at the atomic level.

  2. Phosphonic acid based exchange resins

    DOEpatents

    Horwitz, E.P.; Alexandratos, S.D.; Gatrone, R.C.; Chiarizia, R.

    1995-09-12

    An ion exchange resin is described for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene. 10 figs.

  3. Phosphonic acid based exchange resins

    DOEpatents

    Horwitz, E. Philip; Alexandratos, Spiro D.; Gatrone, Ralph C.; Chiarizia, Ronato

    1995-01-01

    An ion exchange resin for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene.

  4. Exchange rate rebounds after foreign exchange market interventions

    NASA Astrophysics Data System (ADS)

    Hoshikawa, Takeshi

    2017-03-01

    This study examined the rebounds in the exchange rate after foreign exchange intervention. When intervention is strongly effective, the exchange rate rebounds at next day. The effect of intervention is reduced slightly by the rebound after the intervention. The exchange rate might have been 67.12-77.47 yen to a US dollar without yen-selling/dollar-purchasing intervention of 74,691,100 million yen implemented by the Japanese government since 1991, in comparison to the actual exchange rate was 103.19 yen to the US dollar at the end of March 2014.

  5. Intergranular exchange coupling

    NASA Astrophysics Data System (ADS)

    Muller, M. W.; Indeck, R. S.

    1994-02-01

    We evaluate the exchange interaction between neighboring grains of a polycrystalline magnetic material with uniaxial magnetocrystalline anisotropy, based on the energy of the domain wall formed at the portion of the interface in atomic contact. The analysis suggests that previous work [J.-G. Zhu and H. N. Bertram, in Solid State Physics Vol. 46, edited by H. Ehrenreich and T. Turnbull (Academic, San Diego, 1992)] may underestimate the interaction, and it predicts a different dependence on grain size.

  6. Heat exchange apparatus

    DOEpatents

    Degtiarenko, Pavel V.

    2003-08-12

    A heat exchange apparatus comprising a coolant conduit or heat sink having attached to its surface a first radial array of spaced-apart parallel plate fins or needles and a second radial array of spaced-apart parallel plate fins or needles thermally coupled to a body to be cooled and meshed with, but not contacting the first radial array of spaced-apart parallel plate fins or needles.

  7. Heat exchanger tube mounts

    DOEpatents

    Wolowodiuk, W.; Anelli, J.; Dawson, B.E.

    1974-01-01

    A heat exchanger in which tubes are secured to a tube sheet by internal bore welding is described. The tubes may be moved into place in preparation for welding with comparatively little trouble. A number of segmented tube support plates are provided which allow a considerable portion of each of the tubes to be moved laterally after the end thereof has been positioned in preparation for internal bore welding to the tube sheet. (auth)

  8. Scraped surface heat exchangers.

    PubMed

    Rao, Chetan S; Hartel, Richard W

    2006-01-01

    Scraped surface heat exchangers (SSHEs) are commonly used in the food, chemical, and pharmaceutical industries for heat transfer, crystallization, and other continuous processes. They are ideally suited for products that are viscous, sticky, that contain particulate matter, or that need some degree of crystallization. Since these characteristics describe a vast majority of processed foods, SSHEs are especially suited for pumpable food products. During operation, the product is brought in contact with a heat transfer surface that is rapidly and continuously scraped, thereby exposing the surface to the passage of untreated product. In addition to maintaining high and uniform heat exchange, the scraper blades also provide simultaneous mixing and agitation. Heat exchange for sticky and viscous foods such as heavy salad dressings, margarine, chocolate, peanut butter, fondant, ice cream, and shortenings is possible only by using SSHEs. High heat transfer coefficients are achieved because the boundary layer is continuously replaced by fresh material. Moreover, the product is in contact with the heating surface for only a few seconds and high temperature gradients can be used without the danger of causing undesirable reactions. SSHEs are versatile in the use of heat transfer medium and the various unit operations that can be carried out simultaneously. This article critically reviews the current understanding of the operations and applications of SSHEs.

  9. Optimizing exchanger design early

    SciTech Connect

    Lacunza, M.; Vaschetti, G.; Campana, H.

    1987-08-01

    It is not practical for process engineers and designers to make a rigorous economic evaluation for each component of a process due to the loss of time and money. But, it's very helpful and useful to have a method for a quick design evaluation of heat exchangers, considering their important contribution to the total fixed investment in a process plant. This article is devoted to this subject, and the authors present a method that has been proved in some design cases. Linking rigorous design procedures with a quick cost-estimation method provides a good technique for obtaining the right heat exchanger. The cost will be appropriate, sometimes not the lowest because of design restrictions, but a good approach to the optimum in an earlier process design stage. The authors intend to show the influence of the design variables in a shell and tube heat exchanger on capital investment, or conversely, taking into account the general limiting factors of the process such as thermodynamics, operability, corrosion, etc., and/or from the mechanical design of the calculated unit. The last is a special consideration for countries with no access to industrial technology or with difficulties in obtaining certain construction materials or equipment.

  10. Exchange-driven growth.

    PubMed

    Ben-Naim, E; Krapivsky, P L

    2003-09-01

    We study a class of growth processes in which clusters evolve via exchange of particles. We show that depending on the rate of exchange there are three possibilities: (I) Growth-clusters grow indefinitely, (II) gelation-all mass is transformed into an infinite gel in a finite time, and (III) instant gelation. In regimes I and II, the cluster size distribution attains a self-similar form. The large size tail of the scaling distribution is Phi(x) approximately exp(-x(2-nu)), where nu is a homogeneity degree of the rate of exchange. At the borderline case nu=2, the distribution exhibits a generic algebraic tail, Phi(x) approximately x(-5). In regime III, the gel nucleates immediately and consumes the entire system. For finite systems, the gelation time vanishes logarithmically, T approximately [lnN](-(nu-2)), in the large system size limit N--> infinity. The theory is applied to coarsening in the infinite range Ising-Kawasaki model and in electrostatically driven granular layers.

  11. Lightweight Long Life Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Moore, E. K.

    1976-01-01

    A shuttle orbiter flight configuration aluminum heat exchanger was designed, fabricated, and tested. The heat exchanger utilized aluminum clad titanium composite parting sheets for protection against parting sheet pin hole corrosion. The heat exchanger, which is fully interchangeable with the shuttle condensing heat exchanger, includes slurpers (a means for removing condensed water from the downstream face of the heat exchanger), and both the core air passes and slurpers were hydrophilic coated to enhance wettability. The test program included performance tests which demonstrated the adequacy of the design and confirmed the predicted weight savings.

  12. 75 FR 15465 - RMR Real Estate Income Fund, et al.; Notice of Application

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-29

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION RMR Real Estate Income Fund, et al.; Notice of Application March 23, 2010. AGENCY: Securities and Exchange Commission (``Commission''). ACTION: Notice of application under section 6(c) of the...

  13. The Dynamics of Multilateral Exchange

    NASA Astrophysics Data System (ADS)

    Hausken, Kjell; Moxnes, John F.

    The article formulates a dynamic mathematical model where arbitrarily many players produce, consume, exchange, loan, and deposit arbitrarily many goods over time to maximize utility. Consuming goods constitutes a benefit, and producing, exporting, and loaning away goods constitute a cost. Utilities are benefits minus costs, which depend on the exchange ratios and bargaining functions. Three-way exchange occurs when one player acquires, through exchange, one good from another player with the sole purpose of using this good to exchange against the desired good from a third player. Such a triple handshake is not merely a set of double handshakes since the player assigns no interest to the first good in his benefit function. Cognitive and organization costs increase dramatically for higher order exchanges. An exchange theory accounting for media of exchange follows from simple generalization of two-way exchange. The examples of r-way exchange are the triangle trade between Africa, the USA, and England in the 17th and 18th centuries, the hypothetical hypercycle involving RNAs as players and enzymes as goods, and reaction-diffusion processes. The emergence of exchange, and the role of trading agents are discussed. We simulate an example where two-way exchange gives zero production and zero utility, while three-way exchange causes considerable production and positive utility. Maximum utility for each player is reached when exchanges of the same order as the number of players in society are allowed. The article merges micro theory and macro theory within the social, natural, and physical sciences.

  14. Real Time Network Assessment

    DTIC Science & Technology

    2013-07-12

    Demonstrate a simple system Conduct a feasibility assessment of data storage, maintenance, and integration requirements Test a web-based data feed...Real Time Network Assessment Prototype We demonstrated the feasibility of linking near real time network analytics to mashups and web- based...combining similar concepts into single node) Stemmers Thesauri application Network position Statistical common patterns Pronoun identification

  15. Real Estate Career Opportunities.

    ERIC Educational Resources Information Center

    Lyon, Robert; Gardner, Gene

    Designed to provide basic information on the major entry-level career fields in real estate, this document can be used as a reference manual for counselors and instructors. The manual contains general information about the following real estate careers: salesperson, sales manager, broker, land developer, property manager, appraiser, mortgage loan…

  16. Writing for Real Audiences.

    ERIC Educational Resources Information Center

    Shugert, Diane P., Ed.

    1983-01-01

    The focus of the articles in this journal issue is helping students write for real audiences. The document contains the following articles: "Real Audiences: The Only Kind We Write For" (Margaret Queenan); "A Literary Magazine for Middle Grades" (Anthony R. Angelo and Marie-Jeanne Laurent); "Rewarding Understanding and…

  17. 17 CFR 210.12-23 - Mortgage loans on real estate and interest earned on mortgages. 1

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Mortgage loans on real estate... and Content of Schedules § 210.12-23 Mortgage loans on real estate and interest earned on mortgages. 1 Part 1—Mortgage loans on real estate at close of period Column A—List by classification indicated...

  18. Gas Exchange of Algae

    PubMed Central

    Ammann, Elizabeth C. B.; Lynch, Victoria H.

    1967-01-01

    The oxygen production of a photosynthetic gas exchanger containing Chlorella pyrenoidosa (1% packed cell volume) was measured when various concentrations of carbon dioxide were present within the culture unit. The internal carbon dioxide concentrations were obtained by manipulating the entrance gas concentration and the flow rate. Carbon dioxide percentages were monitored by means of electrodes placed directly in the nutrient medium. The concentration of carbon dioxide in the nutrient medium which produced maximal photosynthesis was in the range of 1.5 to 2.5% by volume. Results were unaffected by either the level of carbon dioxide in the entrance gas or the rate of gas flow. Entrance gases containing 2% carbon dioxide flowing at 320 ml/min, 3% carbon dioxide at 135 ml/min, and 4% carbon dioxide at 55 ml/min yielded optimal carbon dioxide concentrations in the particular unit studied. By using carbon dioxide electrodes implanted directly in the gas exchanger to optimize the carbon dioxide concentration throughout the culture medium, it should be possible to design more efficient large-scale units. PMID:4382391

  19. Heat exchanger-accumulator

    DOEpatents

    Ecker, Amir L.

    1980-01-01

    What is disclosed is a heat exchanger-accumulator for vaporizing a refrigerant or the like, characterized by an upright pressure vessel having a top, bottom and side walls; an inlet conduit eccentrically and sealingly penetrating through the top; a tubular overflow chamber disposed within the vessel and sealingly connected with the bottom so as to define an annular outer volumetric chamber for receiving refrigerant; a heat transfer coil disposed in the outer volumetric chamber for vaporizing the liquid refrigerant that accumulates there; the heat transfer coil defining a passageway for circulating an externally supplied heat exchange fluid; transferring heat efficiently from the fluid; and freely allowing vaporized refrigerant to escape upwardly from the liquid refrigerant; and a refrigerant discharge conduit penetrating sealingly through the top and traversing substantially the length of the pressurized vessel downwardly and upwardly such that its inlet is near the top of the pressurized vessel so as to provide a means for transporting refrigerant vapor from the vessel. The refrigerant discharge conduit has metering orifices, or passageways, penetrating laterally through its walls near the bottom, communicating respectively interiorly and exteriorly of the overflow chamber for controllably carrying small amounts of liquid refrigerant and oil to the effluent stream of refrigerant gas.

  20. Hardware for a real-time multiprocessor simulator

    NASA Technical Reports Server (NTRS)

    Blech, R. A.; Arpasi, D. J.

    1984-01-01

    The hardware for a real time multiprocessor simulator (RTMPS) developed at the NASA Lewis Research Center is described. The RTMPS is a multiple microprocessor system used to investigate the application of parallel processing concepts to real time simulation. It is designed to provide flexible data exchange paths between processors by using off the shelf microcomputer boards and minimal customized interfacing. A dedicated operator interface allows easy setup of the simulator and quick interpreting of simulation data. Simulations for the RTMPS are coded in a NASA designed real time multiprocessor language (RTMPL). This language is high level and geared to the multiprocessor environment. A real time multiprocessor operating system (RTMPOS) has also been developed that provides a user friendly operator interface. The RTMPS and supporting software are currently operational and are being evaluated at Lewis. The results of this evaluation will be used to specify the design of an optimized parallel processing system for real time simulation of dynamic systems.

  1. Ion exchange technology assessment report

    SciTech Connect

    Duhn, E.F.

    1992-01-01

    In the execution of its charter, the SRS Ion Exchange Technology Assessment Team has determined that ion exchange (IX) technology has evolved to the point where it should now be considered as a viable alternative to the SRS reference ITP/LW/PH process. The ion exchange media available today offer the ability to design ion exchange processing systems tailored to the unique physical and chemical properties of SRS soluble HLW's. The technical assessment of IX technology and its applicability to the processing of SRS soluble HLW has demonstrated that IX is unquestionably a viable technology. A task team was chartered to evaluate the technology of ion exchange and its potential for replacing the present In-Tank Precipitation and proposed Late Wash processes to remove Cs, Sr, and Pu from soluble salt solutions at the Savannah River Site. This report documents the ion exchange technology assessment and conclusions of the task team.

  2. Ion exchange technology assessment report

    SciTech Connect

    Duhn, E.F.

    1992-12-31

    In the execution of its charter, the SRS Ion Exchange Technology Assessment Team has determined that ion exchange (IX) technology has evolved to the point where it should now be considered as a viable alternative to the SRS reference ITP/LW/PH process. The ion exchange media available today offer the ability to design ion exchange processing systems tailored to the unique physical and chemical properties of SRS soluble HLW`s. The technical assessment of IX technology and its applicability to the processing of SRS soluble HLW has demonstrated that IX is unquestionably a viable technology. A task team was chartered to evaluate the technology of ion exchange and its potential for replacing the present In-Tank Precipitation and proposed Late Wash processes to remove Cs, Sr, and Pu from soluble salt solutions at the Savannah River Site. This report documents the ion exchange technology assessment and conclusions of the task team.

  3. Real Scan Evolution.

    DTIC Science & Technology

    1982-02-01

    Computer Image Generation Visual Simulation Computer Graphics Al gortthm Geometric Model tng 1%ABSTRACT (C.tla. -mm. .00n ad N ue-e""V ONd Ofmi* OF 61"knsee...envtronments. modeled as a single valued el evatYo fnction of horizontal location. The objecttve of the development was to analyze the feasibility of a real...generator capable of creating complex Imagery .in real time? Is the solution amenable to efficient off-lne modeling of complex environments? The Real Scan

  4. Genetic characterisation of Helicobacter pylori isolates from an Argentinean adult population based on cag pathogenicity island right-end motifs, lspA-glmM polymorphism and iceA and vacA genotypes.

    PubMed

    Leanza, A G; Matteo, M J; Crespo, O; Antelo, P; Olmos, J; Catalano, M

    2004-09-01

    Isolates of Helicobacter pylori from 88 patients were characterised by cagA status, cagA pathogenicity island (PAI) right-end motifs, iceA, vacA and lspA-glmM genotypes, primarily by PCR-based analysis, to investigate whether Argentinean isolates differed from those recovered in southern Europe or other Latin American countries. PCR-based analysis of vacA alleles was confirmed by reverse hybridisation in 56 cases, while sequence analysis was performed either when iceA and vacA genotypes could not be determined by PCR, or to investigate PCR and reverse hybridisation vacA genotyping discordance. Typing by lspA-glmM restriction fragment length polymorphism was performed with HhaI and AluI. The pattern of cag PAI right-end motifs and the prevalence of type Ia were similar to those in isolates from southern European countries, with cagA(+)/iceA1/vacA-s1 m1 being the commonest genotype. Reverse hybridisation identified a vacA-s1a/s1b recombinant allele, confirmed by sequencing analysis. Analysis of lspA-glmM genotypes identified at least 73 unrelated strains. Few mixed infections were identified, but in one case, isolates from a single biopsy exhibiting two vacA alleles were shown by lspA-glmM fingerprints to be two unrelated strains. No associated effect on ulcer disease risk was demonstrated by analysis of cagA, vacA and iceA status. Overall, the isolates of H. pylori from Argentina were similar to isolates from southern Europe or Latin American countries, and infections were associated mainly with single H. pylori strains.

  5. Ion-exchange hollow fibers

    NASA Technical Reports Server (NTRS)

    Rembaum, Alan (Inventor); Yen, Shiao-Ping S. (Inventor); Klein, Elias (Inventor)

    1977-01-01

    An ion-exchange hollow fiber is prepared by introducing into the wall of the fiber polymerizable liquid monomers, and polymerizing the monomers therein to form solid, insoluble, cross-linked, ion-exchange resin particles which embed in the wall of the fiber. Excess particles blocking the central passage or bore of the fiber are removed by forcing liquid through the fiber. The fibers have high ion-exchange capacity, a practical wall permeability and good mechanical strength even with very thin wall dimensions. Experimental investigation of bundles of ion-exchange hollow fibers attached to a header assembly have shown the fiber to be very efficient in removing counterions from solution.

  6. Ion-exchange hollow fibers

    NASA Technical Reports Server (NTRS)

    Rembaum, Alan (Inventor); Yen, Shiao-Ping S. (Inventor); Klein, Elias (Inventor)

    1980-01-01

    An ion-exchange hollow fiber is prepared by introducing into the wall of the fiber polymerizable liquid monomers, and polymerizing the monomers therein to form solid, insoluble, cross-linked, ion-exchange resin particles which embed in the wall of the fiber. Excess particles blocking the central passage or bore of the fiber are removed by forcing liquid through the fiber. The fibers have high ion-exchange capacity, a practical wall permeability and good mechanical strength even with very thin wall dimensions. Experimental investigation of bundles of ion-exchange hollow fibers attached to a header assembly have shown the fiber to be very efficient in removing counterions from solution.

  7. Ion-exchange hollow fibers

    NASA Technical Reports Server (NTRS)

    Rembaum, A.; Yen, S. P. S.; Klein, E. (Inventor)

    1976-01-01

    An ion-exchange hollow fiber is prepared by introducing into the wall of the fiber polymerizable liquid monomers, and polymerizing the monomers therein to form solid, insoluble, crosslinked, ion-exchange resin particles which embed in the wall of the fiber. Excess particles blocking the central passage or bore of the fiber are removed by forcing liquid through the fiber. The fibers have high ion-exchange capacity, a practical wall permeability and good mechanical strength even with very thin wall dimensions. Experimental investigation of bundles of ion-exchange hollow fibers attached to a header assembly have shown the fiber to be very efficient in removing counterions from solution.

  8. Making It Real

    ERIC Educational Resources Information Center

    McCartney, Robert; Tenenberg, Josh

    2008-01-01

    Some have proposed that realistic problem situations are better for learning. This issue contains two articles that examine the effects of "making it real" in computer architecture and human-computer interaction.

  9. Monogroove liquid heat exchanger

    NASA Technical Reports Server (NTRS)

    Brown, Richard F. (Inventor); Edelstein, Fred (Inventor)

    1990-01-01

    A liquid supply control is disclosed for a heat transfer system which transports heat by liquid-vapor phase change of a working fluid. An assembly (10) of monogroove heat pipe legs (15) can be operated automatically as either heat acquisition devices or heat discharge sources. The liquid channels (27) of the heat pipe legs (15) are connected to a reservoir (35) which is filled and drained by respective filling and draining valves (30, 32). Information from liquid level sensors (50, 51) on the reservoir (35) is combined (60) with temperature information (55) from the liquid heat exchanger (12) and temperature information (56) from the assembly vapor conduit (42) to regulate filling and draining of the reservoir (35), so that the reservoir (35) in turn serves the liquid supply/drain needs of the heat pipe legs (15), on demand, by passive capillary action (20, 28).

  10. Hybrid Heat Exchangers

    NASA Technical Reports Server (NTRS)

    Tu, Jianping Gene; Shih, Wei

    2010-01-01

    A hybrid light-weight heat exchanger concept has been developed that uses high-conductivity carbon-carbon (C-C) composites as the heat-transfer fins and uses conventional high-temperature metals, such as Inconel, nickel, and titanium as the parting sheets to meet leakage and structural requirements. In order to maximize thermal conductivity, the majority of carbon fiber is aligned in the fin direction resulting in 300 W/m.K or higher conductivity in the fin directions. As a result of this fiber orientation, the coefficient of thermal expansion (CTE) of the C-C composite in both non-fiber directions matches well with the CTE of various high-temperature metal alloys. This allows the joining of fins and parting sheets by using high-temperature braze alloys.

  11. South Atlantic interbasin exchange

    NASA Technical Reports Server (NTRS)

    Rintoul, Stephen Rich

    1991-01-01

    The exchange of mass and heat between the South Atlantic and the neighboring ocean basins was estimated using hydrographic data and inverse methods, in order to gain information on the links between the deep-water formation processes occurring within the Atlantic and the global thermohaline circulation. Results demonstrate that the global thermohaline cell associated with the formation and export of North Atlantic deep water (NADW) is closed primarily by a 'cold water path' in which deep water leaving the Atlantic ultimately returns as intermediate water entering the basin through Drake Passage. This conclusion conflicts with the suggestion by Gordon (1986) that the global thermohaline circulation associated with the formation of NADW is closed primarily by a 'warm water path', in which the export of NADW is compensated by an inflow of warm Indian Ocean thermocline water south of Africa.

  12. Cross-Shelf Exchange.

    PubMed

    Brink, K H

    2016-01-01

    Cross-shelf exchange dominates the pathways and rates by which nutrients, biota, and materials on the continental shelf are delivered and removed. This follows because cross-shelf gradients of most properties are usually far greater than those in the alongshore direction. The resulting transports are limited by Earth's rotation, which inhibits flow from crossing isobaths. Thus, cross-shelf flows are generally weak compared with alongshore flows, and this leads to interesting observational issues. Cross-shelf flows are enabled by turbulent mixing processes, nonlinear processes (such as momentum advection), and time dependence. Thus, there is a wide range of possible effects that can allow these critical transports, and different natural settings are often governed by different combinations of processes. This review discusses examples of representative transport mechanisms and explores possible observational and theoretical paths to future progress.

  13. International Cell Exchange, 1994.

    PubMed

    Lau, M; Terasaki, P I; Park, M S

    1994-01-01

    1. We summarize typings of 40 cells for Class I antigens and 20 cultured cell lines for Class II antigens through the International Cell Exchange in 1994. Serologic Class II typings were compared with DNA typings for the same 20 cells. Two hundred eighty-one laboratories participated in the monthly Class I Serum Exchange. One hundred nineteen serology laboratories and 74 DNA laboratories reported Class II specificities on a monthly basis. 2. The average detection levels, as well as the high detection levels, were determined for 16 A-locus and 27 B-locus antigens. Mean detection rates of 95% or greater average detection were obtained for 12 A-locus and 10 B-locus antigens. Lower than 80% agreement was calculated for one A-locus antigen (A74) and 7 B-locus (B46, B48, B61, B67, B73, B75, B77) antigens. 3. We compared discrepancy rates of 10 A-locus and 7 B-locus antigens typed 3 times or more. The false-negative discrepancy rates, i.e. how often the antigen was missed, were greater for more of the B-locus specificities than for the A-locus antigens. B62, having the highest false-positive rate, tended to be overassigned. The discrepancy rates, especially the false-negative rate, for B70 were shown to decrease over a 7-year period. 4. In 1994, 8 laboratories attained records of total no misses for all analyzed antigens. Twelve laboratories had final records of only one discrepancy, and 5 laboratories had impressive perfect records (zero false negatives and false positives) for their yearly antigen reports. 5. Retyping of 12 Class I and 8 Class II reference cells showed improved detection of antigens. Results of a donor typed 4 times over 11 years demonstrated marked improvement, nearly doubling for A33, B38, and B75. Two cells first typed in 1991, then retyped in 1994, showed improved detection for Class II splits by serology and DNA typing. 6. We updated the list of sequenced Class I Exchange cells. Seven new cells were added as well as confirmatory sequence data for A

  14. Exchange Rates and Old People.

    ERIC Educational Resources Information Center

    Dowd, James J.

    1980-01-01

    Extends earlier work on aging as a process of exchange by focusing on the issue of exchange rates and how they are negotiated. Access to power resources declines with age, placing the old person in the position of negotiating from weakness. (Author)

  15. The NESACS Exchange with Germany

    ERIC Educational Resources Information Center

    Hoffman, Morton Z.; Tanner, Ruth; Strem, Michael

    2007-01-01

    The Northeastern Section of the American Chemical Society (NESACS) is going to host visit to the representatives of the German Chemical Society (GDCh) at their annual exchange program this year. The delegation is expected to spotlight the ACS international effects, in addition to the advantages of the exchange between the two organizations.

  16. Macroreticular chelating ion-exchangers.

    PubMed

    Hirsch, R F; E Gancher, R; Russo, F R

    1970-06-01

    Two macroreticular chelating ion-exchangers have been prepared and characterized. One contains the iminodiacetate group and the second contains the arsonate group as the ion-exchanging site. The macroreticular resins show selectivities among metal ions similar to those of the commercially available naicroreticular chelating resins. Chromatographie separations on the new resins are rapid and sharp.

  17. EXCHANGE. Volume 9-92

    SciTech Connect

    Boltz, J.C.

    1992-09-01

    EXCHANGE is published monthly by the Idaho National Engineering Laboratory (INEL), a multidisciplinary facility operated for the US Department of Energy (DOE). The purpose of EXCHANGE is to inform computer users about about recent changes and innovations in both the mainframe and personal computer environments and how these changes can affect work being performed at DOE facilities.

  18. Technology Performance Exchange (Fact Sheet)

    SciTech Connect

    Not Available

    2012-10-01

    This fact sheet, 'The Technology Performance Exchange' will be presented at the ET Summit, held at the Pasadena Convention Center on October 15-17, 2012. The Technology Performance Exchange will be a centralized, Web-based portal for finding and sharing energy performance data for commercial building technologies.

  19. The Transatlantic Orientation Exchange Project

    ERIC Educational Resources Information Center

    Gisevius, Annette; Weber, Robin A.

    2009-01-01

    The Transatlantic Orientation Exchange/Multiplikatorenschulung im transatlan-tischen Austausch is a collaboration between volunteers and staff in both the US and German AFS organizations. The goal of the project is to increase the level of intercultural learning of German and US secondary education exchange participants and their host families.…

  20. Educators Exchange: A Program Evaluation.

    ERIC Educational Resources Information Center

    Armstrong, William B.

    The Educators Exchange Program (EEP) was established under a training and educational exchange agreement reached by California's San Diego Community College District (SDCCD) and the republic of Mexico. In the program, the District provided a 4-week technological training program to faculty at Centros de Capacitacion Tecnologica Industrial…

  1. High Temperature Heat Exchanger Project

    SciTech Connect

    Anthony E. Hechanova, Ph.D.

    2008-09-30

    The UNLV Research Foundation assembled a research consortium for high temperature heat exchanger design and materials compatibility and performance comprised of university and private industry partners under the auspices of the US DOE-NE Nuclear Hydrogen Initiative in October 2003. The objectives of the consortium were to conduct investigations of candidate materials for high temperature heat exchanger componets in hydrogen production processes and design and perform prototypical testing of heat exchangers. The initial research of the consortium focused on the intermediate heat exchanger (located between the nuclear reactor and hydrogen production plan) and the components for the hydrogen iodine decomposition process and sulfuric acid decomposition process. These heat exchanger components were deemed the most challenging from a materials performance and compatibility perspective

  2. Spot foreign exchange market and time series

    NASA Astrophysics Data System (ADS)

    Petroni, F.; Serva, M.

    2003-08-01

    We investigate high frequency price dynamics in foreign exchange market using data from Reuters information system (the dataset has been provided to us by Olsen and Associates). In our analysis we show that a naïve approach to the definition of price (for example using the spot mid price) may lead to wrong conclusions on price behavior as for example the presence of short term correlations for returns. For this purpose we introduce an algorithm which only uses the non arbitrage principle to estimate real prices from the spot ones. The new definition leads to returns which are not affected by spurious correlations. Furthermore, any apparent information (defined by using Shannon entropy) contained in the data disappears.

  3. Fault-Tolerant Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Izenson, Michael G.; Crowley, Christopher J.

    2005-01-01

    A compact, lightweight heat exchanger has been designed to be fault-tolerant in the sense that a single-point leak would not cause mixing of heat-transfer fluids. This particular heat exchanger is intended to be part of the temperature-regulation system for habitable modules of the International Space Station and to function with water and ammonia as the heat-transfer fluids. The basic fault-tolerant design is adaptable to other heat-transfer fluids and heat exchangers for applications in which mixing of heat-transfer fluids would pose toxic, explosive, or other hazards: Examples could include fuel/air heat exchangers for thermal management on aircraft, process heat exchangers in the cryogenic industry, and heat exchangers used in chemical processing. The reason this heat exchanger can tolerate a single-point leak is that the heat-transfer fluids are everywhere separated by a vented volume and at least two seals. The combination of fault tolerance, compactness, and light weight is implemented in a unique heat-exchanger core configuration: Each fluid passage is entirely surrounded by a vented region bridged by solid structures through which heat is conducted between the fluids. Precise, proprietary fabrication techniques make it possible to manufacture the vented regions and heat-conducting structures with very small dimensions to obtain a very large coefficient of heat transfer between the two fluids. A large heat-transfer coefficient favors compact design by making it possible to use a relatively small core for a given heat-transfer rate. Calculations and experiments have shown that in most respects, the fault-tolerant heat exchanger can be expected to equal or exceed the performance of the non-fault-tolerant heat exchanger that it is intended to supplant (see table). The only significant disadvantages are a slight weight penalty and a small decrease in the mass-specific heat transfer.

  4. Modular heat exchanger

    DOEpatents

    Giardina, A.R.

    1981-03-03

    A shell and tube heat exchanger is described having a plurality of individually removable tube bundle modules. A lattice of structural steel forming rectangular openings therein is placed at each end of a cylindrical shell. Longitudinal structural members are placed in the shell between corners of the rectangular openings situated on opposite ends of the shell. Intermediate support members interconnect the longitudinal supports so as to increase the longitudinal supports rigidity. Rectangular parallelepiped tube bundle modules occupy the space defined by the longitudinal supports and end supports and each include a rectangular tube sheet situated on each end of a plurality of tubes extending there through, a plurality of rectangular tube supports located between the tube sheets, and a tube bundle module stiffening structure disposed about the bundle's periphery and being attached to the tube sheets and tube supports. The corners of each tube bundle module have longitudinal framework members which are mateable with and supported by the longitudinal support members. Intermediate support members constitute several lattices, each of which is situated in a plane between the end support members. The intermediate support members constituting the several lattices extend horizontally and vertically between longitudinal supports of adjacent tube module voids. An alternative embodiment for intermediate support members constitute a series of structural plates situated at the corners of the module voids and having recesses therein for receiving the respective longitudinal support members adjacent thereto, protrusions separating the recesses, and a plurality of struts situated between protrusions of adjacent structural plates. 12 figs.

  5. Energy-Exchange Project

    SciTech Connect

    Not Available

    1982-04-01

    The purpose of the study was to determine what energy savings can be achieved by coordinating the resources and requirements of two facilities, the 26th Ward Water Pollution Control Plant (WPCP) and a housing development named Starrett City with its own total energy system. It was determined that three energy exchange options were economically and technically feasible. These include: the transfer of digester gas produced at the 26th Ward to the boilers at the Starrett City's total energy plant (TEP); the transfer of hot water heated at the TEP to the 26th Ward for space and process heating; and the transfer of coal effluent waste water from the 26th Ward to the condenser cooling systems at the TEP. Technical information is presented to support the findings. The report addresses those tasks of the statement of work dedicated to data acquisition, analysis, and energy conservation strategies internal to the Starrett City TEP and the community it supplies as well as to the 26th Ward WPCP. (MCW)

  6. Aluminum heat exchanger

    SciTech Connect

    Koisuka, M.; Aoki, H.

    1986-11-04

    This patent describes a heat exchanger comprising a flat metal tube for conducting fluid having opposite first and second ends, of metal fins fixed onto outer surfaces of the flat metal tube, first and second header pipes fixedly mounted on the opposite ends of the flat metal tube, respectively, so that the flat metal tube communicates with the interior of the header pipes. Each of the header pipes has a first end that is open and a second end that is closed. An inlet tube is connected to the first end of the first header pipe, and an outlet tube is connected to the first end of the second header pipe. The improvement described here comprises one of the inlet and outlet tubes having an end portion inserted into the first end of the corresponding interconnected header pipe. The end portion has a cut-away portion in the form of a first axial slit extending axially inwardly from an open end at the adjacent end of the one tube. The first axial slit has an axial intermediate portion slightly smaller than the thickness of the flat metal tube, and a tapered portion diverging towards the open end of the first axial slit, and the first end of the flat metal tube extends into the corresponding interconnected header pipe and is closely fitted into the first axial slit.

  7. Electrically switched ion exchange

    SciTech Connect

    Lilga, M.A.; Schwartz, D.T.; Genders, D.

    1997-10-01

    A variety of waste types containing radioactive {sup 137}Cs are found throughout the DOE complex. These waste types include water in reactor cooling basins, radioactive high-level waste (HLW) in underground storage tanks, and groundwater. Safety and regulatory requirements and economics require the removal of radiocesium before these wastes can be permanently disposed of. Electrically Switched Ion Exchange (ESIX) is an approach for radioactive cesium separation that combines IX and electrochemistry to provide a selective, reversible, and economic separation method that also produces little or no secondary waste. In the ESIX process, an electroactive IX film is deposited electrochemically onto a high-surface area electrode, and ion uptake and elution are controlled directly by modulating the potential of the film. For cesium, the electroactive films under investigation are ferrocyanides, which are well known to have high selectivities for cesium in concentrated sodium solutions. When a cathode potential is applied to the film, Fe{sup +3} is reduced to the Fe{sup +2} state, and a cation must be intercalated into the film to maintain charge neutrality (i.e., Cs{sup +} is loaded). Conversely, if an anodic potential is applied, a cation must be released from the film (i.e., Cs{sup +} is unloaded). Therefore, to load the film with cesium, the film is simply reduced; to unload cesium, the film is oxidized.

  8. Starrett City energy exchange

    SciTech Connect

    Not Available

    1982-01-01

    The Starrett City/26th Ward Energy Project is a joint effort of Starrett City (a privately owned and operated 5881-unit high rise housing complex located in Brooklyn, NY) and the city of New York Department of Environmental Protection to develop the means to utilize waste-derived energy produced as by-products of municipal waste water treatment. Starrett City, a development of over 20,000 residents with its own schools, shopping and community centers, and power plant, is located directly across the street from the City of New York's 26th Ward Water Pollution Control Plant. Out of five energy exchange options, a cooperative project team recommended three: (1) transmitting all digester gas from the 26th Ward wastewater sewage-treatment facility to Starrett's cogeneration-type total energy plant (TEP), (2) piping hot water from the Starrett TEP to provide space and process heat to the 26th Ward, and (3) pumping treated effluent from the 26th Ward to the TEP to eliminate the need for Starrett's cooling tower. Starrett City assumed all installation and maintenance costs, both on city property and the TEP. Starrett projects a 53$ million saving in fuel costs over the next 20 years. The project will serve as a model for similar energy resource development efforts and offer the rationale for the private sector and municipalities to build together for the future.

  9. Modular heat exchanger

    DOEpatents

    Giardina, Angelo R. [Marple Township, Delaware County, PA

    1981-03-03

    A shell and tube heat exchanger having a plurality of individually removable tube bundle modules. A lattice of structural steel forming rectangular openings therein is placed at each end of a cylindrical shell. Longitudinal structural members are placed in the shell between corners of the rectangular openings situated on opposite ends of the shell. Intermediate support members interconnect the longitudinal supports so as to increase the longitudinal supports rigidity. Rectangular parallelpiped tube bundle moldules occupy the space defined by the longitudinal supports and end supports and each include a rectangular tube sheet situated on each end of a plurality of tubes extending therethrough, a plurality of rectangular tube supports located between the tube sheets, and a tube bundle module stiffening structure disposed about the bundle's periphery and being attached to the tube sheets and tube supports. The corners of each tube bundle module have longitudinal framework members which are mateable with and supported by the longitudinal support members. Intermediate support members constitute several lattice, each of which is situate d in a plane between the end support members. The intermediate support members constituting the several lattice extend horizontally and vertically between longitudinal supports of adjacent tube module voids. An alternative embodiment for intermediate support members constitute a series of structural plates situated at the corners of the module voids and having recesses therein for receiving the respective longitudinal support members adjacent thereto, protrusions separating the recesses, and a plurality of struts situated between protrusions of adjacent structural plates.

  10. Real-time radiography

    SciTech Connect

    Bossi, R.H.; Oien, C.T.

    1981-02-26

    Real-time radiography is used for imaging both dynamic events and static objects. Fluorescent screens play an important role in converting radiation to light, which is then observed directly or intensified and detected. The radiographic parameters for real-time radiography are similar to conventional film radiography with special emphasis on statistics and magnification. Direct-viewing fluoroscopy uses the human eye as a detector of fluorescent screen light or the light from an intensifier. Remote-viewing systems replace the human observer with a television camera. The remote-viewing systems have many advantages over the direct-viewing conditions such as safety, image enhancement, and the capability to produce permanent records. This report reviews real-time imaging system parameters and components.

  11. Real time obscuration monitoring

    NASA Astrophysics Data System (ADS)

    Agricola, Koos

    2016-09-01

    Recently a real time particle deposition monitoring system is developed. After discussions with optical system engineers a new feature has been added. This enables the real time monitoring of obscuration of exposed optical components by counting the deposited particles and sizing the obscuration area of each particle. This way the Particle Obscuration Rate (POR) can be determined. The POR can be used to determine the risk of product contamination during exposure. The particle size distribution gives information on the type of potential particle sources. The deposition moments will indicate when these sources were present.

  12. Custom, contract, and kidney exchange.

    PubMed

    Healy, Kieran; Krawiec, Kimberly D

    2012-01-01

    In this Essay, we examine a case in which the organizational and logistical demands of a novel form of organ exchange (the nonsimultaneous, extended, altruistic donor (NEAD) chain) do not map cleanly onto standard cultural schemas for either market or gift exchange, resulting in sociological ambiguity and legal uncertainty. In some ways, a NEAD chain resembles a form of generalized exchange, an ancient and widespread instance of the norm of reciprocity that can be thought of simply as the obligation to “pay it forward” rather than the obligation to reciprocate directly with the original giver. At the same time, a NEAD chain resembles a string of promises and commitments to deliver something in exchange for some valuable consideration--that is, a series of contracts. Neither of these salient "social imaginaries" of exchange--gift giving or formal contract--perfectly meets the practical demands of the NEAD system. As a result, neither contract nor generalized exchange drives the practice of NEAD chains. Rather, the majority of actual exchanges still resemble a simpler form of exchange: direct, simultaneous exchange between parties with no time delay or opportunity to back out. If NEAD chains are to reach their full promise for large-scale, nonsimultaneous organ transfer, legal uncertainties and sociological ambiguities must be finessed, both in the practices of the coordinating agencies and in the minds of NEAD-chain participants. This might happen either through the further elaboration of gift-like language and practices, or through a creative use of the cultural form and motivational vocabulary, but not necessarily the legal and institutional machinery, of contract.

  13. Effect of polyamine reagents on exchange capacity in ion exchangers

    NASA Astrophysics Data System (ADS)

    Petrova, T. I.; Dyachenko, F. V.; Bogatyreva, Yu. V.; Borodastov, A. K.; Ershova, I. S.

    2016-05-01

    Effect of compounds involved in complex reagents is described using Helamin 906H reagent as an example. The working exchange capacity of KU-2-8chs cation exchanger in hydrogen form and Amberlite IRA 900Cl anion exchanger in OH form remained almost unchanged when they were used repeatedly to purify water that contained Helamin 906H reagent; in addition, this capacity was the same upon filtration of water that did not contain this reagent. Leakage of total organic carbon was observed earlier than that of calcium ions upon filtration of the solution through the cation exchanger layer. The test results obtained in industrial conditions indicated that using H-OH filters to purify turbine condensate enables the decrease of the concentration of organic and other impurities therein.

  14. Post-quantum key exchange protocols

    NASA Astrophysics Data System (ADS)

    Li, Xiangdong; Leung, Lin; Kwan, Andis Chi-Tung; Zhang, Xiaowen; Kahanda, Dammika; Anshel, Michael

    2006-05-01

    If an eavesdropper Eve is equipped with quantum computers, she can easily break the public key exchange protocols used today. In this paper we will discuss the post-quantum Diffie-Hellman key exchange and private key exchange protocols.

  15. Heat exchange assembly

    DOEpatents

    Lowenstein, Andrew; Sibilia, Marc; Miller, Jeffrey; Tonon, Thomas S.

    2004-06-08

    A heat exchange assembly comprises a plurality of plates disposed in a spaced-apart arrangement, each of the plurality of plates includes a plurality of passages extending internally from a first end to a second end for directing flow of a heat transfer fluid in a first plane, a plurality of first end-piece members equaling the number of plates and a plurality of second end-piece members also equaling the number of plates, each of the first and second end-piece members including a recessed region adapted to fluidly connect and couple with the first and second ends of the plate, respectively, and further adapted to be affixed to respective adjacent first and second end-piece members in a stacked formation, and each of the first and second end-piece members further including at least one cavity for enabling entry of the heat transfer fluid into the plate, exit of the heat transfer fluid from the plate, or 180.degree. turning of the fluid within the plate to create a serpentine-like fluid flow path between points of entry and exit of the fluid, and at least two fluid conduits extending through the stacked plurality of first and second end-piece members for providing first fluid connections between the parallel fluid entry points of adjacent plates and a fluid supply inlet, and second fluid connections between the parallel fluid exit points of adjacent plates and a fluid discharge outlet so that the heat transfer fluid travels in parallel paths through each respective plate.

  16. Hear Exchange Assembly

    DOEpatents

    Lowenstein, Andrew; Sibilia, Marc; Miller, Jeffrey; Tonon, Thomas S.

    2003-05-27

    A heat exchange assembly comprises a plurality of plates disposed in a spaced-apart arrangement, each of the plurality of plates includes a plurality of passages extending internally from a first end to a second end for directing flow of a heat transfer fluid in a first plane, a plurality of first end-piece members equaling the number of plates and a plurality of second end-piece members also equaling the number of plates, each of the first and second end-piece members including a recessed region adapted to fluidly connect and couple with the first and second ends of the plate, respectively, and further adapted to be affixed to respective adjacent first and second end-piece members in a stacked formation, and each of the first and second end-piece members further including at least one cavity for enabling entry of the heat transfer fluid into the plate, exit of the heat transfer fluid from the plate, or 180.degree. turning of the fluid within the plate to create a serpentine-like fluid flow path between points of entry and exit of the fluid, and at least two fluid conduits extending through the stacked plurality of first and second end-piece members for providing first fluid connections between the parallel fluid entry points of adjacent plates and a fluid supply inlet, and second fluid connections between the parallel fluid exit points of adjacent plates and a fluid discharge outlet so that the heat transfer fluid travels in parallel paths through each respective plate.

  17. Charge exchange molecular ion source

    DOEpatents

    Vella, Michael C.

    2003-06-03

    Ions, particularly molecular ions with multiple dopant nucleons per ion, are produced by charge exchange. An ion source contains a minimum of two regions separated by a physical barrier and utilizes charge exchange to enhance production of a desired ion species. The essential elements are a plasma chamber for production of ions of a first species, a physical separator, and a charge transfer chamber where ions of the first species from the plasma chamber undergo charge exchange or transfer with the reactant atom or molecules to produce ions of a second species. Molecular ions may be produced which are useful for ion implantation.

  18. Heat exchanger using graphite foam

    DOEpatents

    Campagna, Michael Joseph; Callas, James John

    2012-09-25

    A heat exchanger is disclosed. The heat exchanger may have an inlet configured to receive a first fluid and an outlet configured to discharge the first fluid. The heat exchanger may further have at least one passageway configured to conduct the first fluid from the inlet to the outlet. The at least one passageway may be composed of a graphite foam and a layer of graphite material on the exterior of the graphite foam. The layer of graphite material may form at least a partial barrier between the first fluid and a second fluid external to the at least one passageway.

  19. 75 FR 51138 - Self-Regulatory Organizations; BATS Exchange, Inc.; Chicago Board Options Exchange, Incorporated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-18

    ...; BATS Exchange, Inc.; Chicago Board Options Exchange, Incorporated; Chicago Stock Exchange, Inc.; EDGA... Securities Exchange LLC; NASDAQ OMX BX, Inc.; The NASDAQ Stock Market LLC; National Stock Exchange, Inc.; New York Stock Exchange LLC; NYSE Amex LLC; NYSE Arca, Inc.; Notice of Designation of Longer Period...

  20. 75 FR 52558 - Self-Regulatory Organizations; BATS Exchange, Inc.; Chicago Board Options Exchange, Incorporated...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-26

    ...; BATS Exchange, Inc.; Chicago Board Options Exchange, Incorporated; Chicago Stock Exchange, Inc.; EDGA... Securities Exchange LLC; NASDAQ OMX BX, Inc.; The NASDAQ Stock Market LLC; National Stock Exchange, Inc.; New York Stock Exchange LLC; NYSE Amex LLC; NYSE Arca, Inc.; Correction August 19, 2010. The Securities...

  1. Real World Graph Connectivity

    ERIC Educational Resources Information Center

    Lind, Joy; Narayan, Darren

    2009-01-01

    We present the topic of graph connectivity along with a famous theorem of Menger in the real-world setting of the national computer network infrastructure of "National LambdaRail". We include a set of exercises where students reinforce their understanding of graph connectivity by analysing the "National LambdaRail" network. Finally, we give…

  2. Real Life 101.

    ERIC Educational Resources Information Center

    Harrington-Lueker, Donna

    1997-01-01

    The Metropolitan Regional Career and Technical Center--the MET--is a multimillion-dollar Rhode Island effort to emphasize learning in real-world situations. Internships have become the torque that drives each student's education plan, focusing on higher level skills rather than on skills specific to a certain trade. (MLF)

  3. Working Like Real Scientists

    ERIC Educational Resources Information Center

    Lunn, Stephen

    2006-01-01

    "Real" science is about formulating and trying to solve practical and conceptual problems on the basis of shared beliefs about the world. Scientists build theories and test hypotheses by observation and experiment. They try their best to eliminate personal bias, and are "extremely canny in their acceptance of the claims of others" (Ziman, 2000).…

  4. Real-World Experiences

    ERIC Educational Resources Information Center

    Borja, Rhea R.

    2006-01-01

    This article presents IISME, a U.S. program that can give educators a real-world experience and that can deepen their subject-matter knowledge. It also presents the experiences of some teachers who are into this program. IISME's summer-fellowship program started out with 40 teachers and 12 companies. The group's growth picked up in 2001, when it…

  5. Real Estate Assistance

    NASA Technical Reports Server (NTRS)

    1997-01-01

    The Commercial Remote Sensing Program at Stennis Space Center assists numerous companies across the United States, in learning to use remote sensing capabilities to enhance their competitiveness. Through the Visiting Investigator Program, SSC helped Coast Delta Realty in Diamondhead, Miss., incorporate remote sensing and Geogrpahic Information System technology for real estate marketing and management.

  6. Being Real for Children.

    ERIC Educational Resources Information Center

    Carter, Margie

    1995-01-01

    Because ready role models for today's children are media-created superheroes and celebrities of television and film, children need real-life role models who guide them into realistic personal and social pathways. As principal adult contacts, teachers can be such role models. Specific strategies for encouraging teachers in this role are presented.…

  7. Convergence Is Real

    ERIC Educational Resources Information Center

    Enyeart, Mike; Staman, E. Michael; Valdes, Jose J., Jr.

    2007-01-01

    The concept of convergence has evolved significantly during recent years. Today, "convergence" refers to the integration of the communications and computing resources and services that seamlessly traverse multiple infrastructures and deliver content to multiple platforms or appliances. Convergence is real. Those in higher education, and especially…

  8. Just like Real Scientists

    ERIC Educational Resources Information Center

    Betteley, Pat

    2009-01-01

    How do you inspire students to keep records like scientists? Share the primary research of real scientists and explicitly teach students how to keep records--that's how! Therefore, a group of third-grade students and their teacher studied the work of famous primatologist Jane Goodall and her modern-day counterpart Ian Gilby. After learning about…

  9. Is It Real Gold?

    ERIC Educational Resources Information Center

    Harris, Harold H.

    1999-01-01

    Features acid tests for determining whether jewelry is "real" gold or simply gold-plated. Describes the carat system of denoting gold content and explains how alloys are used to create various shades of gold jewelry. Addresses the question of whether gold jewelry can turn a wearer's skin green by considering various oxidation reactions.…

  10. Is Optimism Real?

    ERIC Educational Resources Information Center

    Simmons, Joseph P.; Massey, Cade

    2012-01-01

    Is optimism real, or are optimistic forecasts just cheap talk? To help answer this question, we investigated whether optimistic predictions persist in the face of large incentives to be accurate. We asked National Football League football fans to predict the winner of a single game. Roughly half (the partisans) predicted a game involving their…

  11. Marriage exchanges, seed exchanges, and the dynamics of manioc diversity

    PubMed Central

    Delêtre, Marc; McKey, Doyle B.; Hodkinson, Trevor R.

    2011-01-01

    The conservation of crop genetic resources requires understanding the different variables—cultural, social, and economic—that impinge on crop diversity. In small-scale farming systems, seed exchanges represent a key mechanism in the dynamics of crop genetic diversity, and analyzing the rules that structure social networks of seed exchange between farmer communities can help decipher patterns of crop genetic diversity. Using a combination of ethnobotanical and molecular genetic approaches, we investigated the relationships between regional patterns of manioc genetic diversity in Gabon and local networks of seed exchange. Spatially explicit Bayesian clustering methods showed that geographical discontinuities of manioc genetic diversity mirror major ethnolinguistic boundaries, with a southern matrilineal domain characterized by high levels of varietal diversity and a northern patrilineal domain characterized by low varietal diversity. Borrowing concepts from anthropology—kinship, bridewealth, and filiation—we analyzed the relationships between marriage exchanges and seed exchange networks in patrilineal and matrilineal societies. We demonstrate that, by defining marriage prohibitions, kinship systems structure social networks of exchange between farmer communities and influence the movement of seeds in metapopulations, shaping crop diversity at local and regional levels. PMID:22042843

  12. Clinical virology in real time.

    PubMed

    Niesters, Hubert G M

    2002-12-01

    The ability to detect nucleic acids has had and still has a major impact on diagnostics in clinical virology. Both quantitative and qualitative techniques, whether signal or target amplification based systems, are currently used routinely in most if not all virology laboratories. Technological improvements, from automated sample isolation to real time amplification technology, have given the ability to develop and introduce systems for most viruses of clinical interest, and to obtain clinical relevant information needed for optimal antiviral treatment options. Both polymerase chain reaction (PCR) and nucleic acid sequence-based amplification (NASBA) can currently be used together with real time detection to generate results in a short turn-around time and to determine whether variants relevant for antiviral resistance are present. These new technologies enable the introduction of an individual patient disease management concept. Within our clinical setting, we have introduced this e.g. for quantitative detection of Epstein-Barr Virus (EBV) in T-dell depleted allogeneic stem cell transplant patients. This enabled us to develop models for pre-emptive anti B-cell immunotherapy for EBV reactivation, thereby effectively reducing not the incidence of EBV-lymphoproliferative disease but the virus related mortality. Furthermore, additional clinically relevant viruses can now easily be detected simultaneously. It also becomes more feasible to introduce molecular testing for those viruses that can easily be detected using classical virological methods, like culture techniques or antigen detection. Prospective studies are needed to evaluate the clinical importance of the additional positive samples detected. It should however be made clear that a complete exchange of technologies is unlikely to occur, and that some complementary technologies should stay operational enabling the discovery of new viruses. The implementation of these molecular diagnostic technologies furthermore

  13. Phase Change Material Heat Exchangers

    NASA Video Gallery

    NASA’s Game Changing Development is taking on a technologydevelopment and demonstration effort to design, build, and test the next generation of Phase Change Material Heat Exchangers (PCM HXs) on ...

  14. Definition of Magnetic Exchange Length

    SciTech Connect

    Abo, GS; Hong, YK; Park, J; Lee, J; Lee, W; Choi, BC

    2013-08-01

    The magnetostatic exchange length is an important parameter in magnetics as it measures the relative strength of exchange and self-magnetostatic energies. Its use can be found in areas of magnetics including micromagnetics, soft and hard magnetic materials, and information storage. The exchange length is of primary importance because it governs the width of the transition between magnetic domains. Unfortunately, there is some confusion in the literature between the magnetostatic exchange length and a similar distance concerning magnetization reversal mechanisms in particles known as the characteristic length. This confusion is aggravated by the common usage of two different systems of units, SI and cgs. This paper attempts to clarify the situation and recommends equations in both systems of units.

  15. Pu Anion Exchange Process Intensification

    SciTech Connect

    Taylor-Pashow, K.

    2015-10-08

    This project seeks to improve the efficiency of the plutonium anion-exchange process for purifying Pu through the development of alternate ion-exchange media. The objective of the project in FY15 was to develop and test a porous foam monolith material that could serve as a replacement for the current anion-exchange resin, Reillex® HPQ, used at the Savannah River Site (SRS) for purifying Pu. The new material provides advantages in efficiency over the current resin by the elimination of diffusive mass transport through large granular resin beads. By replacing the large resin beads with a porous foam there is much more efficient contact between the Pu solution and the anion-exchange sites present on the material. Several samples of a polystyrene based foam grafted with poly(4-vinylpyridine) were prepared and the Pu sorption was tested in batch contact tests.

  16. Heat pipe array heat exchanger

    DOEpatents

    Reimann, Robert C.

    1987-08-25

    A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

  17. Numerical simulation of heat exchanger

    SciTech Connect

    Sha, W.T.

    1985-01-01

    Accurate and detailed knowledge of the fluid flow field and thermal distribution inside a heat exchanger becomes invaluable as a large, efficient, and reliable unit is sought. This information is needed to provide proper evaluation of the thermal and structural performance characteristics of a heat exchanger. It is to be noted that an analytical prediction method, when properly validated, will greatly reduce the need for model testing, facilitate interpolating and extrapolating test data, aid in optimizing heat-exchanger design and performance, and provide scaling capability. Thus tremendous savings of cost and time are realized. With the advent of large digital computers and advances in the development of computational fluid mechanics, it has become possible to predict analytically, through numerical solution, the conservation equations of mass, momentum, and energy for both the shellside and tubeside fluids. The numerical modeling technique will be a valuable, cost-effective design tool for development of advanced heat exchangers.

  18. Mass exchange processes with input

    NASA Astrophysics Data System (ADS)

    Krapivsky, P. L.

    2015-05-01

    We investigate a system of interacting clusters evolving through mass exchange and supplemented by input of small clusters. Three possibilities depending on the rate of exchange generically occur when input is homogeneous: continuous growth, gelation, and instantaneous gelation. We mostly study the growth regime using scaling methods. An exchange process with reaction rates equal to the product of reactant masses admits an exact solution which allows us to justify the validity of scaling approaches in this special case. We also investigate exchange processes with a localized input. We show that if the diffusion coefficients are mass-independent, the cluster mass distribution becomes stationary and develops an algebraic tail far away from the source.

  19. Characteristics of real futures trading networks

    NASA Astrophysics Data System (ADS)

    Wang, Junjie; Zhou, Shuigeng; Guan, Jihong

    2011-01-01

    Futures trading is the core of futures business, and it is considered as one of the typical complex systems. To investigate the complexity of futures trading, we employ the analytical method of complex networks. First, we use real trading records from the Shanghai Futures Exchange to construct futures trading networks, in which nodes are trading participants, and two nodes have a common edge if the two corresponding investors appear simultaneously in at least one trading record as a purchaser and a seller, respectively. Then, we conduct a comprehensive statistical analysis on the constructed futures trading networks. Empirical results show that the futures trading networks exhibit features such as scale-free behavior with interesting odd-even-degree divergence in low-degree regions, small-world effect, hierarchical organization, power-law betweenness distribution, disassortative mixing, and shrinkage of both the average path length and the diameter as network size increases. To the best of our knowledge, this is the first work that uses real data to study futures trading networks, and we argue that the research results can shed light on the nature of real futures business.

  20. Real-time medical collaboration services over the web.

    PubMed

    Andrikos, Christos; Rassias, Georgios; Tsanakas, Panayiotis; Maglogiannis, Ilias

    2015-08-01

    The gradual shift in modern medical practice, from working alone clinical doctors to MDTs (Multi-Disciplinary Teams), raises the need of online real-time collaboration among geographically distributed medical personnel. The paper presents a Web-based platform, featuring an efficient medical data management and exchange, for hosting real-time collaborative services. The presented work leverages state-of-the-art features of the web (technologies and APIs) to support client-side medical data processing. Moreover, to address the typical bandwidth bottleneck and known scalability issues of centralized data sharing, an indirect RPC (Remote Process Call) scheme is introduced through object synchronization over the WebRTC paradigm.

  1. Vitrification of ion exchange resins

    DOEpatents

    Cicero-Herman, Connie A.; Workman, Rhonda Jackson

    2001-01-01

    The present invention relates to vitrification of ion exchange resins that have become loaded with hazardous or radioactive wastes, in a way that produces a homogenous and durable waste form and reduces the disposal volume of the resin. The methods of the present invention involve directly adding borosilicate glass formers and an oxidizer to the ion exchange resin and heating the mixture at sufficient temperature to produce homogeneous glass.

  2. Ion exchange - Simulation and experiment

    NASA Technical Reports Server (NTRS)

    Herrmann, Cal C.; Finn, John E.

    1991-01-01

    A FORTRAN program for simulating multicomponent adsorption by ion-exchange resins was adapted for use as both an ASPEN-callable module and as a free-standing simulator of the ion-exchange bed. Four polystyrene-divinylbenzene sulfonic acid resins have been characterized for three principal ions. It is concluded that a chelating resin appears appropriate as a heavy-metal trap. The same ASPEN-callable module is used to model this resin when Wilson parameters can be obtained.

  3. Isotopic exchange of uranium. II. Exchange kinetics in solution-organic-ion exchanger systems

    SciTech Connect

    Ryzhinskii, M.V.; Bronzov, P.A.; Vitinskii, M.Yu.

    1987-07-01

    The results of a study of the sorption of uranium and the kinetics of isotopic exchange between uranium(IV) and uranium(VI) in systems consisting of a hydrochloric acid solution and the KU-2-8P and AV-17-10P ion-exchange resins have been studied. It has been shown that the sorption of uranium is limited by diffusion in the sorbent grains and that isotopic exchange is limited by the reaction between uranium(IV) and uranium(VI).

  4. Anion exchange polymer electrolytes

    DOEpatents

    Kim, Yu Seung; Kim, Dae Sik; Lee, Kwan-Soo

    2013-07-23

    Solid anion exchange polymer electrolytes and compositions comprising chemical compounds comprising a polymeric core, a spacer A, and a guanidine base, wherein said chemical compound is uniformly dispersed in a suitable solvent and has the structure: ##STR00001## wherein: i) A is a spacer having the structure O, S, SO.sub.2, --NH--, --N(CH.sub.2).sub.n, wherein n=1-10, --(CH.sub.2).sub.n--CH.sub.3--, wherein n=1-10, SO.sub.2-Ph, CO-Ph, ##STR00002## wherein R.sub.5, R.sub.6, R.sub.7 and R.sub.8 each are independently --H, --NH.sub.2, F, Cl, Br, CN, or a C.sub.1-C.sub.6 alkyl group, or any combination of thereof; ii) R.sub.9, R.sub.10, R.sub.11, R.sub.12, or R.sub.13 each independently are --H, --CH.sub.3, --NH.sub.2, --NO, --CH.sub.nCH.sub.3 where n=1-6, HC.dbd.O--, NH.sub.2C.dbd.O--, --CH.sub.nCOOH where n=1-6, --(CH.sub.2).sub.n--C(NH.sub.2)--COOH where n=1-6, --CH--(COOH)--CH.sub.2--COOH, --CH.sub.2--CH(O--CH.sub.2CH.sub.3).sub.2, --(C.dbd.S)--NH.sub.2, --(C.dbd.NH)--N--(CH.sub.2).sub.nCH.sub.3, where n=0-6, --NH--(C.dbd.S)--SH, --CH.sub.2--(C.dbd.O)--O--C(CH.sub.3).sub.3, --O--(CH.sub.2).sub.n--CH--(NH.sub.2)--COOH, where n=1-6, --(CH.sub.2).sub.n--CH.dbd.CH wherein n=1-6, --(CH.sub.2).sub.n--CH--CN wherein n=1-6, an aromatic group such as a phenyl, benzyl, phenoxy, methylbenzyl, nitrogen-substituted benzyl or phenyl groups, a halide, or halide-substituted methyl groups; and iii) wherein the composition is suitable for use in a membrane electrode assembly.

  5. Hartree potential dependent exchange functional

    NASA Astrophysics Data System (ADS)

    Constantin, Lucian A.; Fabiano, Eduardo; Della Sala, Fabio

    2016-08-01

    We introduce a novel non-local ingredient for the construction of exchange density functionals: the reduced Hartree parameter, which is invariant under the uniform scaling of the density and represents the exact exchange enhancement factor for one- and two-electron systems. The reduced Hartree parameter is used together with the conventional meta-generalized gradient approximation (meta-GGA) semilocal ingredients (i.e., the electron density, its gradient, and the kinetic energy density) to construct a new generation exchange functional, termed u-meta-GGA. This u-meta-GGA functional is exact for the exchange of any one- and two-electron systems, is size-consistent and non-empirical, satisfies the uniform density scaling relation, and recovers the modified gradient expansion derived from the semiclassical atom theory. For atoms, ions, jellium spheres, and molecules, it shows a good accuracy, being often better than meta-GGA exchange functionals. Our construction validates the use of the reduced Hartree ingredient in exchange-correlation functional development, opening the way to an additional rung in the Jacob's ladder classification of non-empirical density functionals.

  6. Numerical analysis of the steam flow field in shell and tube heat exchanger

    NASA Astrophysics Data System (ADS)

    Bartoszewicz, Jarosław; Bogusławski, Leon

    2016-06-01

    In the paper, the results of numerical simulations of the steam flow in a shell and tube heat exchanger are presented. The efficiency of different models of turbulence was tested. In numerical calculations the following turbulence models were used: k-ɛ, RNG k-ɛ, Wilcox k-ω, Chen-Kim k-ɛ, and Lam-Bremhorst k-ɛ. Numerical analysis of the steam flow was carried out assuming that the flow at the inlet section of the heat exchanger were divided into three parts. The angle of steam flow at inlet section was determined individually in order to obtain the best configuration of entry vanes and hence improve the heat exchanger construction. Results of numerical studies were verified experimentally for a real heat exchanger. The modification of the inlet flow direction according to theoretical considerations causes the increase of thermal power of a heat exchanger of about 14%.

  7. Real topological string amplitudes

    NASA Astrophysics Data System (ADS)

    Narain, K. S.; Piazzalunga, N.; Tanzini, A.

    2017-03-01

    We discuss the physical superstring correlation functions in type I theory (or equivalently type II with orientifold) that compute real topological string amplitudes. We consider the correlator corresponding to holomorphic derivative of the real topological amplitude G_{χ } , at fixed worldsheet Euler characteristic χ. This corresponds in the low-energy effective action to N=2 Weyl multiplet, appropriately reduced to the orientifold invariant part, and raised to the power g' = -χ + 1. We show that the physical string correlator gives precisely the holomorphic derivative of topological amplitude. Finally, we apply this method to the standard closed oriented case as well, and prove a similar statement for the topological amplitude F_g.

  8. Real-time cosmology

    NASA Astrophysics Data System (ADS)

    Quercellini, Claudia; Amendola, Luca; Balbi, Amedeo; Cabella, Paolo; Quartin, Miguel

    2012-12-01

    In recent years, improved astrometric and spectroscopic techniques have opened the possibility of measuring the temporal change of radial and transverse position of sources in the sky over relatively short time intervals. This has made at least conceivable to establish a novel research domain, which we dub “real-time cosmology”. We review for the first time most of the work already done in this field, analysing the theoretical framework as well as some foreseeable observational strategies and their capability to constrain models. We first focus on real-time measurements of the overall redshift drift and angular separation shift in distant sources, which allows the observer to trace the background cosmic expansion and large scale anisotropy, respectively. We then examine the possibility of employing the same kind of observations to probe peculiar and proper accelerations in clustered systems, and therefore their gravitational potential. The last two sections are devoted to the future change of the cosmic microwave background on “short” time scales, as well as to the temporal shift of the temperature anisotropy power spectrum and maps. We conclude revisiting in this context the usefulness of upcoming experiments (like CODEX and Gaia) for real-time observations.

  9. Evaluation of Foreign Investment in Power Plants using Real Options

    NASA Astrophysics Data System (ADS)

    Kato, Moritoshi; Zhou, Yicheng

    This paper proposes new methods for evaluating foreign investment in power plants under market uncertainty using a real options approach. We suppose a thermal power plant project in a deregulated electricity market. One of our proposed methods is that we calculate the cash flow generated by the project in a reference year using actual market data to incorporate periodic characteristics of energy prices into a yearly cash flow model. We make the stochastic yearly cash flow model with the initial value which is the cash flow in the reference year, and certain trend and volatility. Then we calculate the real options value (ROV) of the project which has abandonment options using the yearly cash flow model. Another our proposed method is that we evaluate foreign currency/domestic currency exchange rate risk by representing ROV in foreign currency as yearly pay off and exchanging it to ROV in domestic currency using a stochastic exchange rate model. We analyze the effect of the heat rate and operation and maintenance costs of the power plant on ROV, and evaluate exchange rate risk through numerical examples. Our proposed method will be useful for the risk management of foreign investment in power plants.

  10. Radiation Studies with Argentine Ion Exchange Material

    SciTech Connect

    Crawford, C.L.

    2002-06-28

    A recent technology exchange between Argentina Nuclear Energy Commission (CNEA) and the US Department of Energy involved vitrification studies of ion exchange resins. Details of the spent ion exchange resins currently stored at two Argentine nuclear power plants, Atucha I and Embalse, have been presented in earlier reports. The present study examines irradiation of simulant samples of ion exchange resins.

  11. 36 CFR 254.14 - Exchange agreement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ADJUSTMENTS Land Exchanges § 254.14 Exchange agreement. (a) The parties to a proposed exchange may enter into... outstanding interests, stipulation of any necessary cash equalization, and all other terms and conditions necessary to complete an exchange; (2) Inclusion of the terms regarding responsibility for...

  12. 36 CFR 254.14 - Exchange agreement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ADJUSTMENTS Land Exchanges § 254.14 Exchange agreement. (a) The parties to a proposed exchange may enter into... outstanding interests, stipulation of any necessary cash equalization, and all other terms and conditions necessary to complete an exchange; (2) Inclusion of the terms regarding responsibility for...

  13. 36 CFR 254.14 - Exchange agreement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ADJUSTMENTS Land Exchanges § 254.14 Exchange agreement. (a) The parties to a proposed exchange may enter into... outstanding interests, stipulation of any necessary cash equalization, and all other terms and conditions necessary to complete an exchange; (2) Inclusion of the terms regarding responsibility for...

  14. 36 CFR 254.14 - Exchange agreement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ADJUSTMENTS Land Exchanges § 254.14 Exchange agreement. (a) The parties to a proposed exchange may enter into... outstanding interests, stipulation of any necessary cash equalization, and all other terms and conditions necessary to complete an exchange; (2) Inclusion of the terms regarding responsibility for...

  15. 36 CFR 254.14 - Exchange agreement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ADJUSTMENTS Land Exchanges § 254.14 Exchange agreement. (a) The parties to a proposed exchange may enter into... outstanding interests, stipulation of any necessary cash equalization, and all other terms and conditions necessary to complete an exchange; (2) Inclusion of the terms regarding responsibility for...

  16. Real Teaching and Real Learning vs. Narrative Myths about Education

    ERIC Educational Resources Information Center

    Gregory, Marshall

    2007-01-01

    All real classrooms are saturated in the fictional narratives about education from TV and movies that swirl about thickly and persistently in western culture, yet the influence that these fictions exert on real teachers and real students is seldom examined. This article argues that since these fictional narratives nearly always deal in recycled…

  17. The liquid droplet heat exchanger

    NASA Astrophysics Data System (ADS)

    Bruckner, A. P.

    Direct contact heat exchange between a gas and a molten metal dispersed into droplets offers an attractive new approach to increasing the efficiency and decreasing the specific weight of thermal power cycles for space applications. The ability of a droplet heat exchanger to transfer heat directly from a liquid metal to a working gas over a wide temperature range circumvents many of the material limitations of conventional tube type heat exchangers and does away with complicated plumbing systems and their tendency toward simple point failure. Droplet heat exchangers offer large surface to volume ratios in a compact geometry, very low pressure drop and high effectiveness. In the simplest configuration the molten material is sprayed axially through a counterflowing, high pressure inert working gas in an insulated cylindrical chamber. The droplets transfer heat directly to the gas by convection as they traverse the heat exchanger and are subsequently collected for recycling through the heat source. A number of suitable liquid metals and eutectic alloys having negligibly low vapor pressures in the temperature range of 350-1300 K were identified. Experimental studies of droplet formation with mercury demonstrated that near perfect control of droplet size can be easily achieved.

  18. Electrically Switched Cesium Ion Exchange

    SciTech Connect

    JPH Sukamto; ML Lilga; RK Orth

    1998-10-23

    This report discusses the results of work to develop Electrically Switched Ion Exchange (ESIX) for separations of ions from waste streams relevant to DOE site clean-up. ESIX combines ion exchange and electrochemistry to provide a selective, reversible method for radionuclide separation that lowers costs and minimizes secondary waste generation typically associated with conventional ion exchange. In the ESIX process, an electroactive ion exchange film is deposited onto. a high surface area electrode, and ion uptake and elution are controlled directly by modulating the potential of the film. As a result, the production of secondary waste is minimized, since the large volumes of solution associated with elution, wash, and regeneration cycles typical of standard ion exchange are not needed for the ESIX process. The document is presented in two parts: Part I, the Summary Report, discusses the objectives of the project, describes the ESIX concept and the approach taken, and summarizes the major results; Part II, the Technology Description, provides a technical description of the experimental procedures and in-depth discussions on modeling, case studies, and cost comparisons between ESIX and currently used technologies.

  19. Real time Faraday spectrometer

    DOEpatents

    Smith, Jr., Tommy E.; Struve, Kenneth W.; Colella, Nicholas J.

    1991-01-01

    This invention uses a dipole magnet to bend the path of a charged particle beam. As the deflected particles exit the magnet, they are spatially dispersed in the bend-plane of the magnet according to their respective momenta and pass to a plurality of chambers having Faraday probes positioned therein. Both the current and energy distribution of the particles is then determined by the non-intersecting Faraday probes located along the chambers. The Faraday probes are magnetically isolated from each other by thin metal walls of the chambers, effectively providing real time current-versus-energy particle measurements.

  20. Real view thermography

    NASA Astrophysics Data System (ADS)

    Bienkowski, L.; Homma, C.

    2013-01-01

    In this paper we present a novel approach for enhancing active thermography for nondestructive testing. In order to make the evaluation of the data more intuitive a Real View setup is presented that uses a projection technique to let the inspector view and interact with the measurement results directly on the part in a very intuitive way. Moreover we present an analysis approach using a Sobel filter of the pulse-phase result data in order to investigate the detectability of flaws by induction thermography. By projecting this information we give a visual feedback to the operator for optimizing the probability of detection.

  1. Exchange-biased magnetic vortices.

    SciTech Connect

    Hoffmann, A.; Sort, J.; Buchanan, K. S.; Nogues, J.; Inst. Catalana de Recerca i Estudis Avancats; Univ. Autonoma de Barcelona

    2008-07-01

    This paper reviews our work on the interplay between exchange bias due to the coupling of a ferromagnet to an antiferromagnet and the formation of magnetic vortices, which occur due to the patterning of a ferromagnet. Depending on the thermal and magnetic history, a variety of different effects can be observed. Thermal annealing in a saturating magnetic field establishes a spatially homogeneous exchange bias with a uniform unidirectional anisotropy. This results in an angular dependence of the magnetization reversal mode, which can be either via magnetization rotation or vortex nucleation and annihilation. In contrast, thermal annealing in a field smaller than the vortex annihilation field imprints the ferromagnetic vortex configuration in the antiferromagnet with high fidelity resulting in unusual asymmetric hysteresis loops. Furthermore, we discuss how the interfacial nature of the exchange bias can modify the vortex magnetization along the thickness of the ferromagnet.

  2. Atmosphere-surface exchange measurements.

    PubMed

    Dabberdt, W F; Lenschow, D H; Horst, T W; Zimmerman, P R; Oncley, S P; Delany, A C

    1993-06-04

    The exchange of various trace species and energy at the earth's surface plays an important role in climate, ecology, and human health and welfare. Surface exchange measurements can be difficult to obtain yet are important to understand physical processes, assess environmental and global change impacts, and develop robust parameterizations of atmospheric processes. The physics and turbulent structure of the atmospheric boundary layer are reviewed as they contribute to dry surface exchange rates (fluxes). Micrometeorological, budget, and enclosure techniques used to measure or estimate surface fluxes are described, along with their respective advantages and limitations. Various measurement issues (such as site characteristics, sampling considerations, sensor attributes, and flow distortion) impact on the ability to obtain representative surface-based and airborne flux data.

  3. Pion exchange at high energies

    SciTech Connect

    Jones, L.M.

    1980-07-01

    The state of Regge pion exchange calculations for high-energy reactions is reviewed. Experimental evidence is summarized to show that (i) the pion trajectory has a slope similar to that of other trajectories; (ii) the pion exchange contribution can dominate contributions of higher trajectories up to quite a large energy; (iii) many two-body cross sections with large pion contributions can be fit only by models which allow for kinematical conspiracy at t=0. The theory of kinematic conspiracy is reviewed for two-body amplitudes, and calculations of the conspiring pion--Pomeron cut discussed. The author then summarizes recent work on pion exchange in Reggeized Deck models for multiparticle final states, with emphasis on the predictions of various models (with and without resonances) for phases of the partial wave amplitudes.

  4. Ultrafast Optical Magnetization Modulation in Exchange Biased Ferromagnetic Layers

    NASA Astrophysics Data System (ADS)

    Ju, Ganping; Nurmikko, Arto; Farrow, R. F. C.

    1998-03-01

    We have recently shown how the use of femtosecond laser pulses can be employed to study the spin dynamics and magnetization kinetics associated with hot electrons in ferromagnetic thin films on a psec timescale. (G. Ju et al, Phys. Rev. B (Jan. 1998)) Briefly, energetic electrons are promoted by interband excitation and the relaxation process in the nonequilibrium spin system are probed via transient Kerr effect. Here we report our first observations in the MnPt/FeNi antiferromagnetic/ferromagnetic bilayer system by such an experimental approach. The exchange biasing AF layer is selective optically excited with femtosecond laser pulses, while the induced changes in the magnetic properties of the FM layer are probed in real time. We have identified two types of effects: those ( ~300ps) intermediated by ultrafast lattice heating (unpinning of the exchange bias), and those ( ~10ps)which originate from ballistic electron transport within the bilayer. The preliminary results offer some insight for the dynamics of the exchange coupling and open up possibilities for ultrafast optical switching of the exchange biased system. Research supported by NSF.

  5. Thermoacoustics with idealized heat exchangers and no stack.

    PubMed

    Wakeland, Ray Scott; Keolian, Robert M

    2002-06-01

    A model is developed for thermoacoustic devices that have neither stack nor regenerator. These "no-stack" devices have heat exchangers placed close together in an acoustic standing wave of sufficient amplitude to allow individual parcels of gas to enter both exchangers. The assumption of perfect heat transfer in the exchangers facilitates the construction of a simple model similar to the "moving parcel picture" that is used as a first approach to stack-based engines and refrigerators. The model no-stack cycle is shown to have potentially greater inviscid efficiency than a comparable stack model. However, losses from flow through the heat exchangers and on the walls of the enclosure are greater than those in a stack-based device due to the increased acoustic pressure amplitude. Estimates of these losses in refrigerators are used to compare the possible efficiencies of real refrigerators made with or without a stack. The model predicts that no-stack refrigerators can exceed stack-based refrigerators in efficiency, but only for particular enclosure geometries.

  6. Making Virtual Exchange/Telecollaboration Mainstream--Large Scale Exchanges

    ERIC Educational Resources Information Center

    Hagley, Eric

    2016-01-01

    Language educators' goals include promoting cultural understanding and improving the language skills of their students. Virtual Exchange (VE) is a powerful means to do this. Students in English as a Foreign Language (EFL) classrooms often have few opportunities to communicate with other users of English. VE gives them virtual mobility, enabling…

  7. Grafted methylenediphosphonate ion exchange resins

    DOEpatents

    Trochimcznk, A.W.; Gatrone, R.C.; Alexandratos, S.; Horwitz, E.P.

    1997-04-08

    An ion exchange resin is disclosed that is comprised of an insoluble copolymer onto which are grafted pendent groups that provide 1.0 to about 10 mmol/g dry weight phosphorus. The pendent groups have the formula as shown in the patent wherein R is hydrogen, a cation or mixtures thereof; and R{sup 1} is hydrogen or an C{sub 1}-C{sub 2} alkyl group. The resin also contains zero to about 5 mmol/g dry weight of pendent aromatic sulfonate groups. Processes for making and using an ion exchange resin are also disclosed.

  8. The Electrically Controlled Exchange Bias

    NASA Astrophysics Data System (ADS)

    Harper, Jacob

    Controlling magnetism via voltage in the virtual absence of electric current is the key to reduce power consumption while enhancing processing speed, integration density and functionality in comparison with present-day information technology. Almost all spintronic devices rely on tailored interface magnetism. Controlling magnetism at thin-film interfaces, preferably by purely electrical means, is therefore a key challenge to better spintronics. However, there is no direct interaction between magnetization and electric fields, thus making voltage control of magnetism in general a scientific challenge. The significance of controlled interface magnetism started with the exchange-bias effect. Exchange bias is a coupling phenomenon at magnetic interfaces that manifests itself prominently in the shift of the ferromagnetic hysteresis loop along the magnetic-field axis. Various attempts on controlling exchange bias via voltage utilizing different scientific principles have been intensively studied recently. The majority of present research is emphasizing on various complex oxides. Our approach can be considered as a paradigm shift away from complex oxides. We focus on a magnetoelectric antiferromagnetic simple oxide Cr2O3. From a combination of experimental and theoretical efforts, we show that the (0001) surface of magnetoelectric Cr2O3 has a roughness-insensitive, electrically switchable magnetization. Using a ferromagnetic Pd/Co multilayer deposited on the (0001) surface of a Cr2O3 single crystal, we achieve reversible, room-temperature isothermal switching of the exchange-bias between positive and negative values by reversing the electric field while maintaining a permanent magnetic field. This is a significant scientific breakthrough providing a new route towards potentially revolutionizing information technology. In addition, a second path of electrically controlled exchange bias is introduced by exploiting the piezoelectric property of BaTiO3. An exchange-bias Co

  9. Grafted methylenediphosphonate ion exchange resins

    DOEpatents

    Trochimcznk, Andrzej W.; Gatrone, Ralph C.; Alexandratos, Spiro; Horwitz, E. Philip

    1998-01-27

    An ion exchange resin is disclosed that is comprised of an insoluble copolymer onto which are grafted pendent groups that provide 1.0 to about 10 mmol/g dry weight phosphorous. The pendent groups have the formula ##STR1## wherein R is hydrogen, a cation or mixtures thereof; and R.sup.1 is hydrogen or an C.sub.1 -C.sub.2 alkyl group. The resin also contains zero to about 5 mmol/g dry weight of pendent aromatic sulfonate groups. Processes for making and using an ion exchange-resin are also disclosed.

  10. Grafted methylenediphosphonate ion exchange resins

    DOEpatents

    Trochimcznk, Andrzej W.; Gatrone, Ralph C.; Alexandratos, Spiro; Horwitz, E. Philip

    1997-01-01

    An ion exchange resin is disclosed that is comprised of an insoluble copolymer onto which are grafted pendent groups that provide 1.0 to about 10 mmol/g dry weight phosphorous. The pendent groups have the formula ##STR1## wherein R is hydrogen, a cation or mixtures thereof; and R.sup.1 is hydrogen or an C.sub.1 -C.sub.2 alkyl group. The resin also contains zero to about 5 mmol/g dry weight of pendent aromatic sulfonate groups. Processes for making and using an ion exchange resin are also disclosed.

  11. Virtual and real photons

    NASA Astrophysics Data System (ADS)

    Meulenberg, Andrew, Jr.

    2011-09-01

    Maxwell did not believe in photons. However, his equations lead to electro-magnetic field structures that are considered to be photonic by Quantum ElectroDynamics (QED). They are complete, relativistically correct, and unchallenged after nearly 150 years. However, even though his far-field solution has been considered as the basis for photons, as they stand and are interpreted, they are better fitted to the concept of virtual rather than to real photons. Comparison between staticcharge fields, near-field coupling, and photonic radiation will be made and the distinctions identified. The question of similarities in, and differences between, the two will be addressed. Implied assumptions in Feynman's "Lectures" could lead one to believe that he had provided a general classical electrodynamics proof that an orbital electron must radiate. While his derivation is correct, two of the conditions defined do not always apply in this case. As a result, the potential for misinterpretation of his proof (as he himself did earlier) for this particular case has some interesting implications. He did not make the distinction between radiation from a bound electron driven by an external alternating field and one falling in a nuclear potential. Similar failures lead to misinterpreting the differences between virtual and real photons.

  12. Melting barriers to faunal exchange across ocean basins.

    PubMed

    McKeon, C Seabird; Weber, Michele X; Alter, S Elizabeth; Seavy, Nathaniel E; Crandall, Eric D; Barshis, Daniel J; Fechter-Leggett, Ethan D; Oleson, Kirsten L L

    2016-02-01

    Accelerated loss of sea ice in the Arctic is opening routes connecting the Atlantic and Pacific Oceans for longer periods each year. These changes may increase the ease and frequency with which marine birds and mammals move between the Pacific and Atlantic Ocean basins. Indeed, recent observations of birds and mammals suggest these movements have intensified in recent decades. Reconnection of the Pacific and Atlantic Ocean basins will present both challenges to marine ecosystem conservation and an unprecedented opportunity to examine the ecological and evolutionary consequences of interoceanic faunal exchange in real time. To understand these changes and implement effective conservation of marine ecosystems, we need to further develop modeling efforts to predict the rate of dispersal and consequences of faunal exchange. These predictions can be tested by closely monitoring wildlife dispersal through the Arctic Ocean and using modern methods to explore the ecological and evolutionary consequences of these movements.

  13. Selection of the air heat exchanger operating in a gas turbine air bottoming cycle

    NASA Astrophysics Data System (ADS)

    Chmielniak, Tadeusz; Czaja, Daniel; Lepszy, Sebastian

    2013-12-01

    A gas turbine air bottoming cycle consists of a gas turbine unit and the air turbine part. The air part includes a compressor, air expander and air heat exchanger. The air heat exchanger couples the gas turbine to the air cycle. Due to the low specific heat of air and of the gas turbine exhaust gases, the air heat exchanger features a considerable size. The bigger the air heat exchanger, the higher its effectiveness, which results in the improvement of the efficiency of the gas turbine air bottoming cycle. On the other hand, a device with large dimensions weighs more, which may limit its use in specific locations, such as oil platforms. The thermodynamic calculations of the air heat exchanger and a preliminary selection of the device are presented. The installation used in the calculation process is a plate heat exchanger, which is characterized by a smaller size and lower values of the pressure drop compared to the shell and tube heat exchanger. Structurally, this type of the heat exchanger is quite similar to the gas turbine regenerator. The method on which the calculation procedure may be based for real installations is also presented, which have to satisfy the economic criteria of financial profitability and cost-effectiveness apart from the thermodynamic criteria.

  14. Is the "glass ceiling" a real problem for women physicists in Argentina?

    NASA Astrophysics Data System (ADS)

    Frechero, Marisa A.; Amador, Ana; Pastor, Antonio J. Ramirez; Tamarit, Francisco

    2015-12-01

    We evaluate the distribution of female physicists in the Argentinean workforce, analyzing the distribution of women at different levels of education and research using several indicators. Although important imbalances still occur, our findings are encouraging and the distribution of female physicists seems to be changing for the better.

  15. A fundamentally new approach to air-cooled heat exchangers.

    SciTech Connect

    Koplow, Jeffrey P.

    2010-01-01

    We describe breakthrough results obtained in a feasibility study of a fundamentally new architecture for air-cooled heat exchangers. A longstanding but largely unrealized opportunity in energy efficiency concerns the performance of air-cooled heat exchangers used in air conditioners, heat pumps, and refrigeration equipment. In the case of residential air conditioners, for example, the typical performance of the air cooled heat exchangers used for condensers and evaporators is at best marginal from the standpoint the of achieving maximum the possible coefficient of performance (COP). If by some means it were possible to reduce the thermal resistance of these heat exchangers to a negligible level, a typical energy savings of order 30% could be immediately realized. It has long been known that a several-fold increase in heat exchanger size, in conjunction with the use of much higher volumetric flow rates, provides a straight-forward path to this goal but is not practical from the standpoint of real world applications. The tension in the market place between the need for energy efficiency and logistical considerations such as equipment size, cost and operating noise has resulted in a compromise that is far from ideal. This is the reason that a typical residential air conditioner exhibits significant sensitivity to reductions in fan speed and/or fouling of the heat exchanger surface. The prevailing wisdom is that little can be done to improve this situation; the 'fan-plus-finned-heat-sink' heat exchanger architecture used throughout the energy sector represents an extremely mature technology for which there is little opportunity for further optimization. But the fact remains that conventional fan-plus-finned-heat-sink technology simply doesn't work that well. Their primary physical limitation to performance (i.e. low thermal resistance) is the boundary layer of motionless air that adheres to and envelops all surfaces of the heat exchanger. Within this boundary layer

  16. 77 FR 39315 - Self-Regulatory Organizations; BOX Options Exchange LLC; Notice of Filing and Immediate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-02

    ... market system and, in general, to protect investors and the public interest. The Exchange believes that the data demonstrates that there is sufficient investor interest and demand to extend the PIP Pilot... provide investors with real and significant price improvement regardless of the size of the order. \\6\\...

  17. 77 FR 51593 - Self-Regulatory Organizations; EDGX Exchange, Inc.; Notice of Filing and Immediate Effectiveness...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-24

    ... was adopted to provide Users \\3\\ with real-time analytical tools to measure latency of orders to and... contracted directly with Correlix to use its RaceTeam latency measurement service for EDGX.\\4\\ The Exchange... terminating the revenue sharing agreement will not burden competition since the latency measurement tools...

  18. 77 FR 51594 - Self-Regulatory Organizations; EDGA Exchange, Inc.; Notice of Filing and Immediate Effectiveness...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-24

    ... was adopted to provide Users \\3\\ with real-time analytical tools to measure latency of orders to and... contracted directly with Correlix to use its RaceTeam latency measurement service for EDGA.\\4\\ The Exchange... terminating the revenue sharing agreement will not burden competition since the latency measurement tools...

  19. An Approach to Semantic Interoperability for Improved Capability Exchanges in Federations of Systems

    ERIC Educational Resources Information Center

    Moschoglou, Georgios

    2013-01-01

    This study seeks an affirmative answer to the question whether a knowledge-based approach to system of systems interoperation using semantic web standards and technologies can provide the centralized control of the capability for exchanging data and services lacking in a federation of systems. Given the need to collect and share real-time…

  20. 77 FR 47150 - Self-Regulatory Organizations; EDGA Exchange, Inc.; Notice of Filing and Immediate Effectiveness...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-07

    ... SR-EDGA-2011-19,\\3\\ the Exchange made available the EDGA Book Feed (``EDGA Book Feed''), a data feed... identification numbers and administrative messages. The EDGA Book Feed offers real-time data, thereby allowing... the best bid and offer which must be made available under the Act. EDGA chooses to make the...

  1. 77 FR 47152 - Self-Regulatory Organizations; EDGX Exchange, Inc.; Notice of Filing and Immediate Effectiveness...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-07

    ...-EDGX-2011-18,\\3\\ the Exchange made available the EDGX Book Feed (``EDGX Book Feed''), a data feed that... numbers and administrative messages. The EDGX Book Feed offers real-time data, thereby allowing Member..., unlike the best bid and offer which must be made available under the Act. EDGX chooses to make...

  2. Nonadiabatic exchange dynamics during adiabatic frequency sweeps.

    PubMed

    Barbara, Thomas M

    2016-04-01

    A Bloch equation analysis that includes relaxation and exchange effects during an adiabatic frequency swept pulse is presented. For a large class of sweeps, relaxation can be incorporated using simple first order perturbation theory. For anisochronous exchange, new expressions are derived for exchange augmented rotating frame relaxation. For isochronous exchange between sites with distinct relaxation rate constants outside the extreme narrowing limit, simple criteria for adiabatic exchange are derived and demonstrate that frequency sweeps commonly in use may not be adiabatic with regard to exchange unless the exchange rates are much larger than the relaxation rates. Otherwise, accurate assessment of the sensitivity to exchange dynamics will require numerical integration of the rate equations. Examples of this situation are given for experimentally relevant parameters believed to hold for in-vivo tissue. These results are of significance in the study of exchange induced contrast in magnetic resonance imaging.

  3. Toxigenic Alternaria species from Argentinean blueberries.

    PubMed

    Greco, M; Patriarca, A; Terminiello, L; Fernández Pinto, V; Pose, G

    2012-03-15

    Blueberries are traditionally consumed in North America, some European countries and Japan. In Argentina, the blueberry crop is profitable because production starts in November, when the northern hemisphere lacks fresh fruit. Fungal contaminants can grow and produce mycotoxins in fresh fruit. The aims of this work were to identify the main genera of the mycobiota of blueberries grown in Argentina and to determine the toxicogenic potential, pathogenicity and host specificity of the species isolated. The genus Alternaria was the main component of the blueberry mycobiota (95%); minor proportions of Phoma spp. (4%) and Penicillium spp. (1%) were also isolated. According to their sporulation patterns, 127 Alternaria isolates belonged to the Alternaria tenuissima species-group, 5 to the Alternaria alternata species-group and 2 to the Alternaria arborescens species-group. The last mentioned species-group was not isolated at 5°C. Of the 134 isolates, 61% were toxicogenic in autoclaved rice; 97% of these produced alternariol (AOH) in a range from 0.14 to 119.18 mg/kg, 95% produced alternariol methylether (AME) in a range from 1.23 to 901.74 mg/kg and 65% produced tenuazonic acid (TA) in a range from 0.13 to 2778 mg/kg. Fifty two isolates co-produced the three mycotoxins. According to the size of the lesion that they caused on blueberries, the isolates were classified as slightly pathogenic, moderately pathogenic and very pathogenic. No significant differences in pathogenicity were found on different blueberry varieties. In this work, high incidence and toxicogenic potential of the Alternaria isolates from blueberries were demonstrated. Thus, more studies should be done to evaluate the health risk posed by the presence of the Alternaria toxins in blueberries and in the manufactured by-products.

  4. Our International Art Exchange Project.

    ERIC Educational Resources Information Center

    Cocciolone, Kathy R.

    1989-01-01

    Discusses an international art exchange project designed to teach fifth-grade students that the culture of a country is reflected in its art and that art is a universal language. Describes the contributions from Scotland, Mexico, Saudi Arabia, Egypt, Japan, and India. Points out ways to use materials in schools. (KO)

  5. Identifiability, exchangeability and confounding revisited

    PubMed Central

    Greenland, Sander; Robins, James M

    2009-01-01

    In 1986 the International Journal of Epidemiology published "Identifiability, Exchangeability and Epidemiological Confounding". We review the article from the perspective of a quarter century after it was first drafted and relate it to subsequent developments on confounding, ignorability, and collapsibility. PMID:19732410

  6. "Bottle-Brush" Heat Exchanger

    NASA Technical Reports Server (NTRS)

    Tward, E.; Gatewood, J. R.

    1982-01-01

    Heat exchanger consists of a metal tube with wires extending inward from wall. Conduction of heat along wires improves heat transfer to gas or other filling. Fluid is heated throughout the cross section of tube. Suggested applications are refrigerators, heat engines, thermal instrumentation, and heat switches.

  7. Fock exchange in FLAPW method

    NASA Astrophysics Data System (ADS)

    Shishidou, Tatsuya; Oguchi, Tamio

    2008-03-01

    Fock exchange potential has distinct features which cannnot be seen in the LDA exchange potential. (i) It is self-interaction free potential and (ii) nonlocal potential and thus state-dependent potential. With appropriate correlation effects added, these two features may produce significantly improved results over the conventional LDA results, as one can witness in the GW calculations. Massidda et al. (1993) proposed a way to calculate Fock exchange potential of extended solids within the FLAPW method. Their idea was to apply Weinert's Poisson solver to infinite lattice summation as is done for the Hartree potential calculation. Due to the long range nature of Coulomb interaction, one encounters singularity problem in this process. They handled it by simply extending Gygi's prescription (1986), which was originally developed for the norm-conserving pseudopotential framework. In this paper, we present our formula in calculating Fock exchange matrix of solids based on the FLAPW method. Following Massidda's idea, we use Weinert's Poisson solver. However, in treating the Coulomb singularity, we have developed more accurate way: the occupied eigenfunctions in Fock operator are expanded upto the second order in terms of q vector based on the k.p perturbation theory, whearas Gygi's way corresponds to the zeroth order expansion. With this higher order expansion, one can achieve faster convergence for the Brillouin zone integration appearing in the Fock operator.

  8. Knowledge Exchange with Sistema Scotland

    ERIC Educational Resources Information Center

    Allan, Julie; Moran, Nikki; Duffy, Celia; Loening, Gica

    2010-01-01

    This paper reports on a knowledge exchange project, funded by the Scottish Funding Council and undertaken by a group of researchers from three higher education institutions in Scotland and the project partner, Sistema Scotland. This newly established charity is attempting to implement a major programme of social change, developed in Venezuela,…

  9. Educational Telecomputing Projects: Interpersonal Exchanges.

    ERIC Educational Resources Information Center

    Harris, Judi

    1995-01-01

    Six different types of interpersonal exchanges, or educational telecomputing activities that incorporate the use of interpersonal skills are presented: (1) "keypals"; (2) global classrooms; (3) electronic "appearances"; (4) electronic monitoring; (5) question-and-answer services; and (6) impersonations. From this presentation,…

  10. Lightweight long life heat exchanger

    NASA Technical Reports Server (NTRS)

    Moore, E. K.

    1975-01-01

    The design, fabrication, and evaluation of a full scale shuttle-type condensing heat exchanger constructed of aluminum and utilizing aluminum clad titanium parting sheets is described. A long term salt spray test of candidate parting sheet specimens is described. The results of an investigation into an alternate method of making composite sheet material are discussed.

  11. Legal Exchange: Necessity and Opportunity

    ERIC Educational Resources Information Center

    Norberg, Charles R.

    1975-01-01

    The International Legal Exchange Program (ILEP) arranges for lawyers from the U.S. or foreign countries to have several months of training in countries different from their own. The program offers an opportunity to strengthen world order under law through better understanding. (Author/PG)

  12. Calculations of Shipboard Heat Exchangers,

    DTIC Science & Technology

    1980-04-18

    Constrained moticn is created by the external exciting forces - pumps, compresors , fars, agitators. During the heat exchange distinguish the phenomena...cast tcttozs. (5). fcr fla*/plane covers/caps. FOOTNOTE 1. Is taken stall value. !NDFOCINOIE. Additional requirements fox the dished bcttcss. -w j DOC

  13. Homans on Exchange: Hedonism Revived

    ERIC Educational Resources Information Center

    Abrahamsson, Bengt

    1970-01-01

    George C. Homan's theory on social exchange is critically examined and found to have serious shortcomings with regard to its deductive and inductive aspects. An expecially prominent shortcoming concerns the tautological character of his concept of reward," which makes his theory deductively unclear and empirically untestable. Homan's critique…

  14. Primer on nuclear exchange models

    SciTech Connect

    Hafemeister, David

    2014-05-09

    Basic physics is applied to nuclear force exchange models between two nations. Ultimately, this scenario approach can be used to try and answer the age old question of 'how much is enough?' This work is based on Chapter 2 of Physics of Societal Issues: Calculations on National Security, Environment and Energy (Springer, 2007 and 2014)

  15. [CO2-gas exchange of mosses following water vapour uptake].

    PubMed

    Lange, O L

    1969-03-01

    The CO2-gas exchange of dry mosses which were exposed to air of high water vapour content has been followed. Some moss species behave as do lichens and aerophilic green algae: they are able to take up enough water vapour to make a rather high photosynthetic activity possible. Other species lack this ability. They need liquid water for reactivation of photosynthesis, as do poikilohydric ferns and phanerogams. In this respect too the mosses are located between the real thallophytes and the cormophytes. From this point of view they are useful objects for studying the relationships between water vapour reactivation, morphological organisation and ecological capability.

  16. Near real-time geomagnetic data for space weather applications in the European sector

    NASA Astrophysics Data System (ADS)

    Johnsen, M. G.; Hansen, T. L.

    2012-12-01

    Tromsø Geophysical Observatory (TGO) is responsible for making and maintaining long time-series of geomagnetic measurements in Norway. TGO is currently operating 3 geomagnetic observatories and 11 variometer stations from southern Norway to Svalbard . Data from these 14 locations are acquired, processed and made available for the user community in near real-time. TGO is participating in several European Union (EU) and European Space Agency (ESA) space weather related projects where both near real-time data and derived products are provided. In addition the petroleum industry is benefiting from our real-time data services for directional drilling. Near real-time data from TGO is freely available for non-commercial purposes. TGO is exchanging data in near real-time with several institutions, enabling the presentation of near real-time geomagnetic data from more than 40 different locations in Fennoscandia and Greenland. The open exchange of non real-time geomagnetic data has been successfully going on for many years through services such as the world data center in Kyoto, SuperMAG, IMAGE and SPIDR. TGO's vision is to take this one step further and make the exchange of near real-time geomagnetic data equally available for the whole community. This presentation contains an overview of TGO, our activities and future aims. We will show how our near real-time data are presented. Our contribution to the space weather forecasting and nowcasting effort in the EU and ESA will be presented with emphasis on our real-time auroral activity index and brand new auroral activity monitor and electrojet tracker.

  17. Augmented reality aiding collimator exchange at the LHC

    NASA Astrophysics Data System (ADS)

    Martínez, Héctor; Fabry, Thomas; Laukkanen, Seppo; Mattila, Jouni; Tabourot, Laurent

    2014-11-01

    Novel Augmented Reality techniques have the potential to have a large positive impact on the way remote maintenance operations are carried out in hazardous areas, e.g. areas where radiation doses that imply careful planning and optimization of maintenance operations are present. This paper describes an Augmented Reality strategy, system and implementation for aiding the remote collimator exchange in the LHC, currently the world's largest and highest-energy particle accelerator. The proposed system relies on marker detection and multi-modal augmentation in real-time. A database system has been used to ensure flexibility. The system has been tested in a mock-up facility, showing real time performance and great potential for future use in the LHC. The technical-scientific difficulties identified during the development of the system and the proposed solutions described in this paper may help the development of future Augmented Reality systems for remote handling in scientific facilities.

  18. Comparing realness between real objects and images at various resolutions

    NASA Astrophysics Data System (ADS)

    Masaoka, Kenichiro; Emoto, Masaki; Sugawara, Masayuki; Nojiri, Yuji

    2007-02-01

    Image resolution is one of the important factors for visual realness. We performed subjective assessments to examine the realness of images at six different resolutions, ranging from 19.5 cpd (cycles per degree) to 156 cpd. A paired-comparison procedure was used to quantify the realness of six images versus each other or versus the real object. Three objects were used. Both real objects and images were viewed through a synopter, which removed horizontal disparity and presented the same image to both eyes. Sixty-five observers were asked to choose the viewed image which was closer to the real object and appeared to be there naturally for each pair of stimuli selected from the group of six images and the real object. It was undisclosed to the observers that real objects were included in the stimuli. The paired comparison data were analyzed using the Bradley-Terry model. The results indicated that realness of an image increased as the image resolution increased up to about 40-50 cpd, which corresponded to the discrimination threshold calculated based on the observers' visual acuity, and reached a plateau above this threshold.

  19. 40 CFR 63.654 - Heat exchange systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... section. (1) All heat exchangers that are in organic HAP service within the heat exchange system that...., the heat exchange system does not contain any heat exchangers that are in organic HAP service as... exchange system in organic HAP service or from each heat exchanger exit line for each heat exchanger...

  20. The improved broadband Real-Time Seismic Network in Romania

    NASA Astrophysics Data System (ADS)

    Neagoe, C.; Ionescu, C.

    2009-04-01

    Starting with 2002 the National Institute for Earth Physics (NIEP) has developed its real-time digital seismic network. This network consists of 96 seismic stations of which 48 broad band and short period stations and two seismic arrays are transmitted in real-time. The real time seismic stations are equipped with Quanterra Q330 and K2 digitizers, broadband seismometers (STS2, CMG40T, CMG 3ESP, CMG3T) and strong motions sensors Kinemetrics episensors (+/- 2g). SeedLink and AntelopeTM (installed on MARMOT) program packages are used for real-time (RT) data acquisition and exchange. The communication from digital seismic stations to the National Data Center in Bucharest is assured by 5 providers (GPRS, VPN, satellite communication, radio lease line and internet), which will assure the back-up communications lines. The processing centre runs BRTT's AntelopeTM 4.10 data acquisition and processing software on 2 workstations for real-time processing and post processing. The Antelope Real-Time System is also providing automatic event detection, arrival picking, event location and magnitude calculation. It provides graphical display and reporting within near-real-time after a local or regional event occurred. Also at the data center was implemented a system to collect macroseismic information using the internet on which macro seismic intensity maps are generated. In the near future at the data center will be install Seiscomp 3 data acquisition processing software on a workstation. The software will run in parallel with Antelope software as a back-up. The present network will be expanded in the near future. In the first half of 2009 NIEP will install 8 additional broad band stations in Romanian territory, which also will be transmitted to the data center in real time. The Romanian Seismic Network is permanently exchanging real -time waveform data with IRIS, ORFEUS and different European countries through internet. In Romania, magnitude and location of an earthquake are now

  1. Phosphonic acid based ion exchange resins

    DOEpatents

    Horwitz, E. Philip; Alexandratos, Spiro D.; Gatrone, Ralph C.; Chiarizia, Ronato

    1996-01-01

    An ion exchange resin for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene diphosphonic acid with styrene, acrylonitrile and divinylbenzene.

  2. Phosphonic acid based ion exchange resins

    DOEpatents

    Horwitz, E. Philip; Alexandratos, Spiro D.; Gatrone, Ralph C.; Chiarizia, Ronato

    1994-01-01

    An ion exchange resin for extracting metal ions from a liquid waste stream. An ion exchange resin is prepared by copolymerizing a vinylidene disphosphonic acid with styrene, acrylonitrile and divinylbenzene.

  3. The Kinetics of Isotopic Exchange Reactions.

    ERIC Educational Resources Information Center

    Logan, S. R.

    1990-01-01

    Discussed are the kinetic interactions of these chemical processes and the determination of the actual order of such reactions. Included are multiple exchange, catalytic exchange with deuterium, and depletion of the original substrate. (CW)

  4. A simple nonlocal model for exchange.

    PubMed

    Janesko, Benjamin G

    2009-12-21

    This work presents a new nonlocal model for the exchange energy density. The model is obtained from the product of the Kohn-Sham one-particle density matrix used to construct exact [Hartree-Fock-like (HF)] exchange, and an approximate density matrix used to construct local spin-density approximation (LSDA) exchange. The proposed exchange energy density has useful formal properties, including correct spin and coordinate scaling and the correct uniform limit. It can readily be evaluated in finite basis sets, with a computational scaling intermediate between HF exchange and semilocal quantities such as the noninteracting kinetic energy density. Applications to representative systems indicate that its properties are typically intermediate between HF and LSDA exchange, and often similar to global hybrids of HF and LSDA exchange. The model is proposed as a novel "Rung 3.5" ingredient for constructing approximate exchange-correlation functionals.

  5. Learn about the Environmental Information Exchange Network

    EPA Pesticide Factsheets

    States, territories, and tribes can partner with EPA to exchange standardized data to improve its quality, increase its availability, and integrate it better across different sources using connecting nodes, xml schema, and a data exchange template.

  6. Test procedure for cation exchange chromatography

    SciTech Connect

    Cooper, T.D.

    1994-08-24

    The purpose of this test plan is to demonstrate the synthesis of inorganic antimonate ion exchangers and compare their performance against the standard organic cation exchangers. Of particular interest is the degradation rate of both inorganic and organic cation exchangers. This degradation rate will be tracked by determining the ion exchange capacity and thermal stability as a function of time, radiation dose, and chemical reaction.

  7. Real time polarimetric dehazing.

    PubMed

    Mudge, Jason; Virgen, Miguel

    2013-03-20

    Remote sensing is a rich topic due to its utility in gathering detailed accurate information from locations that are not economically feasible traveling destinations or are physically inaccessible. However, poor visibility over long path lengths is problematic for a variety of reasons. Haze induced by light scatter is one cause for poor visibility and is the focus of this article. Image haze comes about as a result of light scattering off particles and into the imaging path causing a haziness to appear on the image. Image processing using polarimetric information of light scatter can be used to mitigate image haze. An imaging polarimeter which provides the Stokes values in real time combined with a "dehazing" algorithm can automate image haze removal for instant applications. Example uses are to improve visual display providing on-the-spot detection or imbedding in an active control loop to improve viewing and tracking while on a moving platform. In addition, removing haze in this manner allows the trade space for a system operational waveband to be opened up to bands which are object matched and not necessarily restricted by scatter effects.

  8. The real problem.

    PubMed

    Godfrey, M

    1997-01-01

    I really was dismayed to see the basic cause of all our planet's problems buried in the September/October 96 issue: "...religious zealots might wreck the family planning needs of a billion people...." Let's face hard facts: all these problems would go away if the planet's population were small enough. What we really need to establish is what the population of the earth should be, and then set out to achieve that population as soon as possible. All of our efforts to reduce automobile pollution, the amount of reactor waste, the number of species being obliterated, etc., are just postponing the inevitable. What we need to look at, and keep track of, are those factors that encourage expanding population and discourage population control. For example, most businesses like to see the population expand so they can have a growing customer base. I truly appreciate your efforts. But if we are going to get anywhere we have to clearly identify the real problem. And then we have to break it down into manageable pieces and go to work on them. Otherwise we are going to keep looking at the graphs and wringing our hands as this accumulation of problems builds until it sweeps over us like a giant tsunami.

  9. Bistability in radiative heat exchange

    NASA Astrophysics Data System (ADS)

    Rudakov, V. I.; Ovcharov, V. V.; Prigara, V. P.

    2008-08-01

    The possibility of a bistable regime in systems with radiative heat exchange is theoretically demonstrated for the first time. The transfer characteristics of a radiation-closed stationary system have been calculated, in which the radiator is a blackbody and the absorber is made of a material with the absorptivity sharply increasing in a certain temperature interval. The radiator and absorber are separated by a vacuum gap. The heat exchange between the system and the environment is controlled by varying the flow rate of a heat-transfer agent cooling the absorber. The output parameter of a bistable system is the absorber temperature, while the input parameter can be either the radiator temperature or the heat-transfer agent flow rate. Depending on the choice of the input parameter, the transfer characteristic of the system is either represented by a usual S-like curve or has an inverted shape.

  10. Energy exchanges in reconnection outflows

    NASA Astrophysics Data System (ADS)

    Lapenta, Giovanni; Goldman, Martin V.; Newman, David L.; Markidis, Stefano

    2017-01-01

    Reconnection outflows are highly energetic directed flows that interact with the ambient plasma or with flows from other reconnection regions. Under these conditions the flow becomes highly unstable and chaotic, as any flow jets interacting with a medium. We report here massively parallel simulations of the two cases of interaction between outflow jets and between a single outflow with an ambient plasma. We find in both case the development of a chaotic magnetic field, subject to secondary reconnection events that further complicate the topology of the field lines. The focus of the present analysis is on the energy balance. We compute each energy channel (electromagnetic, bulk, thermal, for each species) and find where the most energy is exchanged and in what form. The main finding is that the largest energy exchange is not at the reconnection site proper but in the regions where the outflowing jets are destabilized.

  11. Role exchange in medical interpretation.

    PubMed

    White, Kari; Laws, M Barton

    2009-12-01

    Prior research has documented that medical interpreters engage in non-conduit roles during medical visits. However, agreement on the appropriateness of these roles and their impact on the medical encounter have not yet been achieved. The purpose of this study was to identify non-conduit behavior (role exchange), elucidate the various forms it takes among different types of interpreters, and assess its potential to affect clinical encounters. Using audiotapes from 13 pediatric outpatient visits, we found that "chance" and uncertified hospital interpreters engaged in role exchange by assuming the provider's role; the patient's role; and taking other non-interpretive roles such as socializing with mothers or acting in one's alternate professional role. These behaviors occurred frequently among both types of interpreters while the provider was actively engaged in conducting the medical visit. In most instances, the interpreter did not make his or her behavior transparent to either the provider or the mother. Implications for interpreter and provider training are discussed.

  12. Heat exchanger and related methods

    DOEpatents

    Turner, Terry D.; McKellar, Michael G.

    2015-12-22

    Heat exchangers include a housing having an inlet and an outlet and forming a portion of a transition chamber. A heating member may form another portion of the transition chamber. The heating member includes a first end having a first opening and a second end having a second opening larger than the first opening. Methods of conveying a fluid include supplying a first fluid into a transition chamber of a heat exchanger, supplying a second fluid into the transition chamber, and altering a state of a portion of the first fluid with the second fluid. Methods of sublimating solid particles include conveying a first fluid comprising a material in a solid state into a transition chamber, heating the material to a gaseous state by directing a second fluid through a heating member and mixing the first fluid and the second fluid.

  13. SODIUM-WATER HEAT EXCHANGER

    DOEpatents

    Simmons, W.R.; Koch, L.J.

    1962-04-17

    A heat exchanger comprising a tank for hot liquid and a plurality of concentric, double tubes for cool liquid extending vertically through the tank is described. These tubes are bonded throughout most of their length but have an unbonded portion at both ends. The inner tubes extend between headers located above and below the tanmk and the outer tubes are welded into tube sheets forming the top and bottom of the tank at locations in the unbonded portions of the tubes. (AEC)

  14. [Biofouling of heat exchange tubes].

    PubMed

    Montero, F; Pintado, J L

    1994-01-01

    We compared the biofouling behavior of different materials (admiralty brass, stainless steel, and titanium) commonly used to construct heat exchangers in thermoelectric plants. The incidence of film formation on the loss of heat during transference was assessed, and analyzed in terms of plant efficiency and corrosion, both general and localized development. Our results showed that the resistance of titanium and stainless steel to corrosion was similar, and much better than that of admiralty brass. Biofouling, however, was higher in the first two materials.

  15. On exchangeable continuous variable systems

    SciTech Connect

    Koenig, Robert; Wolf, Michael M.

    2009-01-15

    We investigate permutation-invariant continuous variable quantum states and their covariance matrices. We provide a complete characterization of the latter with respect to permutation invariance and exchangeability and representing convex combinations of tensor power states. On the level of the respective density operators this leads to necessary criteria for all these properties which become necessary and sufficient for Gaussian states. For these we use the derived results to provide de Finetti-type theorems for various distance measures.

  16. North Atlantic Nordic Seas exchanges

    NASA Astrophysics Data System (ADS)

    Hansen, B.; Østerhus, S.

    2000-02-01

    The northeastern part of the North Atlantic is unique in the sense that it is much warmer in the surface than other ocean areas at similar latitudes. The main reason for this is the large northward transport of heat that extends to high latitudes and crosses the Greenland-Scotland Ridge to enter the Nordic Seas and the Arctic. There the warm Atlantic water is converted to colder water masses that return southwards over the ridge partly as surface outflows and partly as overflows through the deep passages across the ridge. In this paper, the state of knowledge on the exchanges especially across the eastern part of the Greenland-Scotland Ridge is reviewed based on results from the ICES NANSEN (North Atlantic-Norwegian Sea Exchanges) project, from the Nordic WOCE project and from other sources. The accumulated evidence allows us to describe the exchanges in fair detail; the origins of the waters, the patterns of their flow towards and over the ridge and their ultimate fate. There is also increasing information on temporal variations of the exchanges although dynamical changes are still not well understood. Quantitative estimates for the volume transport of most of the overflow branches seem reasonably well established, and transport measurements of the Atlantic inflows to the Nordic Seas are approaching acceptable levels of confidence which allows preliminary budgets to be presented. The deep overflows are driven by pressure gradients set up by the formation of deep and intermediate water. The dominance of deep overflows over surface outflows in the water budget argues that this thermohaline forcing also dominates over direct wind stress and estuarine forcing in driving the Atlantic water inflow across the Greenland-Scotland Ridge, while wind stress seems to influence the characteristics and distribution of the Atlantic water north of the ridge.

  17. Electrically controlled cesium ion exchange

    SciTech Connect

    Lilga, M.

    1996-10-01

    Several sites within the DOE complex (Savannah River, Idaho, Oak Ridge and Hanford) have underground storage tanks containing high-level waste resulting from nuclear engineering activities. To facilitate final disposal of the tank waste, it is advantageous to separate and concentrate the radionuclides for final immobilization in a vitrified glass matrix. This task proposes a new approach for radionuclide separation by combining ion exchange (IX) and electrochemistry to provide a selective and economic separation method.

  18. Heat exchanger expert system logic

    NASA Technical Reports Server (NTRS)

    Cormier, R.

    1988-01-01

    The reduction is described of the operation and fault diagnostics of a Deep Space Network heat exchanger to a rule base by the application of propositional calculus to a set of logic statements. The value of this approach lies in the ease of converting the logic and subsequently implementing it on a computer as an expert system. The rule base was written in Process Intelligent Control software.

  19. 2 CFR 200.440 - Exchange rates.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 2 Grants and Agreements 1 2014-01-01 2014-01-01 false Exchange rates. 200.440 Section 200.440 Grants and Agreements Office of Management and Budget Guidance for Grants and Agreements OFFICE OF... Exchange rates. (a) Cost increases for fluctuations in exchange rates are allowable costs subject to...

  20. Trust and Transitions in Modes of Exchange

    ERIC Educational Resources Information Center

    Cheshire, Coye; Gerbasi, Alexandra; Cook, Karen S.

    2010-01-01

    In this study, we investigate the relationship between uncertainty and trust in exogenous shifts in modes of social exchange (i.e., those that are not initiated by the individuals in a given exchange system). We explore how transitions from a high uncertainty environment (reciprocal exchange) to lower-uncertainty environments (nonbinding or…

  1. Cryogenic Heat Exchanger with Turbulent Flows

    ERIC Educational Resources Information Center

    Amrit, Jay; Douay, Christelle; Dubois, Francis; Defresne, Gerard

    2012-01-01

    An evaporator-type cryogenic heat exchanger is designed and built for introducing fluid-solid heat exchange phenomena to undergraduates in a practical and efficient way. The heat exchanger functions at liquid nitrogen temperature and enables cooling of N[subscript 2] and He gases from room temperatures. We present first the experimental results of…

  2. Pressurized bellows flat contact heat exchanger interface

    NASA Technical Reports Server (NTRS)

    Voss, Fred E. (Inventor); Howell, Harold R. (Inventor); Winkler, Roger V. (Inventor)

    1990-01-01

    Disclosed is an interdigitated plate-type heat exchanger interface. The interface includes a modular interconnect to thermally connect a pair or pairs of plate-type heat exchangers to a second single or multiple plate-type heat exchanger. The modular interconnect comprises a series of parallel, plate-type heat exchangers arranged in pairs to form a slot therebetween. The plate-type heat exchangers of the second heat exchanger insert into the slots of the modular interconnect. Bellows are provided between the pairs of fins of the modular interconnect so that when the bellows are pressurized, they drive the plate-type heat exchangers of the modular interconnect toward one another, thus closing upon the second heat exchanger plates. Each end of the bellows has a part thereof a thin, membrane diaphragm which readily conforms to the contours of the heat exchanger plates of the modular interconnect when the bellows is pressurized. This ensures an even distribution of pressure on the heat exchangers of the modular interconnect thus creating substantially planar contact between the two heat exchangers. The effect of the interface of the present invention is to provide a dry connection between two heat exchangers whereby the rate of heat transfer can be varied by varying the pressure within the bellows.

  3. Pharmaceutical Applications of Ion-Exchange Resins

    ERIC Educational Resources Information Center

    Elder, David

    2005-01-01

    The historical uses of ion-exchanged resins and a summary of the basic chemical principles involved in the ion-exchanged process are discussed. Specific applications of ion-exchange are provided that include drug stabilization, pharmaceutical excipients, taste-masking agents, oral sustained-release products, topical products for local application…

  4. Power and Dependence in Intimate Exchange

    ERIC Educational Resources Information Center

    van de Rijt, Arnout; Macy, Michael W.

    2006-01-01

    A division of labor is mediated by exchange of valued goods and services. We use social exchange theory to extend this principal to "labors of love." Sexual activity in a close personal relationship seems outside the domain of bargaining and exchange. Nevertheless, we explore the possibility that this most intimate of human relations is influenced…

  5. Neighbourhood Book Exchanges: Localising Information Practices

    ERIC Educational Resources Information Center

    Webster, Tenny; Gollner, Kathleen; Nathan, Lisa

    2015-01-01

    Introduction: Through this paper we report on an exploratory study into the design and use of neighbourhood book exchanges in North America. We identify dominant media framings of these book exchanges in North America, along with claims made concerning the influence of the exchanges. We compare the media claims with insights from interviews with…

  6. The Analysis of Information Exchange Capability for Battlefield Networks Using M&S Techniques of the NetSPIN

    DTIC Science & Technology

    2013-06-01

    battlefield network, which are modeled and simulated using the OPNET . In this paper, we suggest the analysis method of information exchange capability for...battlefield network, which are modeled and simulated using the OPNET . In this paper, we suggest the analysis method of information exchange capability...SPIDER, ATCIS, OPNET 1. INTRODUCTION For the NCW (Network Centric Warfare) that networks of a battlefield are interconnected in real time, the

  7. Oxidizer heat exchanger component test

    NASA Technical Reports Server (NTRS)

    Kanic, P. G.

    1988-01-01

    The RL10-IIB engine, is capable of multimode thrust operation. The engine operates at two low-thrust levels: tank head idle (THI), approximately 1 to 2 percent of full thrust; and pumped idle, 10 percent of full thrust. Operation at THI provides vehicle propellant settling thrust and efficient thermal conditioning; PI operation provides vehicle tank prepressurization and maneuver thrust for low-g deployment. Stable combustion of the RL10-IIB engine during the low-thrust operating modes can be accomplished by using a heat exchanger to supply gaseous oxygen to the propellant injector. The oxidized heat exchanger (OHE) vaporizes the liquid oxygen using hydrogen as the energy source. This report summarizes the test activity and post-test data analysis for two possible heat exchangers, each of which employs a completely different design philosophy. One design makes use of a low-heat transfer (PHT) approach in combination with a volume to attenuate pressure and flow oscillations. The test data showed that the LHT unit satisfied the oxygen exit quality of 0.95 or greater in both the THI and PI modes while maintaining stability. The HHT unit fulfilled all PI requirements; data for THI satisfactory operation is implied from experimental data that straddle the exact THI operating point.

  8. EXCHANGE

    SciTech Connect

    Boltz, J.C.

    1993-01-01

    This report contains the following news headlines: ADPE acquisition process made easy with SRP; scientific reference material available; ORPS WordPerfect macro setup procedure; system managed storage is here; LIBSPOOL for MVS mainframe end-users; training center course schedule for February 1993; enjoy NJOY; scientific user services staff decreased; new release of Forwarn, a static source code analysis tool for FORTRAN programs; out of the cold with HEAT; coping cells from one table to another in word perfect; used PC equipment pool; and video training.

  9. EXCHANGE

    SciTech Connect

    Boltz, J.C.

    1993-03-01

    This report discusses the following topics on computer environments: Releasing computer software outside EG G Idaho; Ilford digital photo imager; mandatory upgrade of PC ORPS software; ORPS host computer upgrade; EROB computer users see network change; password expiration notice; big iron still has place in HPC market; handy scripts to copy and move files; more on workstation password expiration; training center course schedule for April 1993; Microsoft Word Version 5.1a- button bar; file attributes can provide you greater flexibility; constructing a personal WordPerfect dictionary; and Windows shortcuts.

  10. 76 FR 79254 - Self-Regulatory Organizations; EDGA Exchange, Inc.; EDGX Exchange, Inc.; Order Approving Proposed...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-21

    .... Registration of Market Makers The Exchanges propose to give Members the option to register as Market Makers... thereunder. \\6\\ 17 CFR 240.15c3-1. The Exchanges could suspend or terminate the registration of a Market Maker if the Exchange(s) determine(s) that the Market Maker: Substantially or continually fails...

  11. Market Motivations for Voluntary Carbon Disclosure in Real Estate Industry

    NASA Astrophysics Data System (ADS)

    Ufere, Kalu Joseph; Alias, Buang; Godwin Uche, Aliagha

    2016-07-01

    Climate change mitigation in developing economies is a balancing act, between economic development and environmental sustainability. The need for market friendly determinants for low carbon economy, without compromising economic development is of essence. The aim of the study is to determine market friendly factors, which motivates voluntary carbon information disclosure, in the real estate industry. The study modeled economic factor with three variables and financial market factor with three variables against voluntary carbon information disclosure in the real estate industry. Structural equation modeling was used for the modeling and content analysis was used to collect data on the level of voluntary carbon information disclosure, from 2013 annual reports of 126 real estate sector companies listed in the Kuala Lumpur Stock Exchange (KLSE). The model achieved a good fit, and was acceptable prediction. The results show that financial market factor has a significant predictive influence on voluntary carbon disclosure. The application of the result is that financial market factor is has a significantly positive influence on companies’ willingness to make voluntary carbon disclosure in the real estate industry. The result may be limited to the real estate industry that is highly leveraged on syndicated fund.

  12. Contribution of Δ(1232) to real photon radiative corrections for elastic electron-proton scattering

    NASA Astrophysics Data System (ADS)

    Gerasimov, R. E.; Fadin, V. S.

    2016-12-01

    Here we consider the contribution of the Δ(1232) resonance to the real photon radiative corrections for elastic ep-scattering. The effect is found to be small for past experiments studying the unpolarized cross section, as well as for the recent VEPP-3 experiment investigating two-photon exchange effects by the precision measurement of the {e}+/- p-scattering cross section ratio.

  13. Offering Remotely Triggered, Real-Time Experiments in Electrochemistry for Distance Learners

    ERIC Educational Resources Information Center

    Saxena, Sachin; Satsangee, Soami P.

    2014-01-01

    Remote access to real experiments is crucial for distance learners to experience the sciences. The exploitation of technology for this purpose is advantageous in global teaching and in exchange of ideas on a single front irrespective of distance barriers. Implementation of the distance method leads to cost-effective integrated-e-learning where…

  14. The real new economy.

    PubMed

    Farrell, Diana

    2003-10-01

    During the soar-and-swoon days of the late 1990s, many people believed that information technology, and the Internet in particular, were "changing everything" in business. A fundamental change did happen in the 1990s, but it was less about technology than about competition. Under director Diana Farrell, the McKinsey Global Institute has conducted an extensive study of productivity and its connection to corporate IT spending and use during that period. The study revealed that information technology is important--but not central--to the fate of industries and individual companies. So if information technology was not the primary factor in the productivity surge, what was? The study points to competition and innovation. In those industries that saw increases in competitive intensity, managers were forced to innovate aggressively to protect their revenues and profits. Those innovations--in products, business practices, and technology--led to the gains in productivity. In fact, a critical dynamic of the new economy--the real new economy--is the virtuous cycle of competition, innovation, and productivity growth. Managers can innovate in many ways, but during the 1990s, information technology was a particularly powerful tool, for three reasons: First, IT enabled the development of attractive new products and efficient new business processes. Second, it facilitated the rapid industrywide diffusion of innovations. And third, it exhibited strong scale economies--its benefits multiplied rapidly as its use expanded. This article reveals surprising data on how various industries in the United States and Europe were affected by competition, innovation, and information technology in the 1990s and offers insights about how managers can get more from their IT investments.

  15. Heat exchangers of gas turbine engines

    NASA Astrophysics Data System (ADS)

    Baranov, Iu. F.; Mitin, B. M.

    1991-07-01

    The papers presented in this volume focus on methods for studying the thermal and hydraulic characteristics of heat exchangers used in gas turbine engines and methods for the analysis and experimental investigation of the dynamic characteristics of heat exchangers with different coolant flow schemes, including cryogenic heat exchangers. In particular, attention is given to the effect of tube bundle parameters on the dimensional and mass characteristics of high-temperature heat exchangers, a numerical method for calculating the dynamic characteristics of a fuel-air heat exchanger with a buffer cavity, and an experimental study of the air drying process in air coolers.

  16. Optimal counter-current exchange networks

    NASA Astrophysics Data System (ADS)

    Farr, Robert S.; Mao, Yong

    2016-11-01

    We present a general analysis of exchange devices linking their efficiency to the geometry of the exchange surface and supply network. For certain parameter ranges, we show that the optimal exchanger consists of densely packed pipes which can span a thin sheet of large area (an "active layer"), which may be crumpled into a fractal surface and supplied with a fractal network of pipes. We derive the efficiencies of such exchangers, showing the potential for significant gains compared to regular exchangers (where the active layer is flat), using parameters relevant to biological systems.

  17. The ARAC-RODOS-WSPEEDI Information Exchange Project

    SciTech Connect

    Sullivan, T J

    1999-09-01

    Under the auspices of a US DOE-JAPAN Memorandum of Understanding JAERI and LLNL agreed to develop and evaluate a prototype information exchange protocol for nuclear accident emergency situations. This project received some interest from the US DOS and FEMA as it fits nicely under the umbrella of the G-7's GEMINI (Global Emergency Management Information Network Initiative) project. Because of LLNL/ARAC and JAERV WSPEEDI interest in nuclear accident consequence assessment and hazard prediction on all scales, to include global, we were happy to participate. Subsequent to the Spring 1997 RODOS-ARAC Workshop a Memorandum of Agreement was developed to enhance mutual collaboration on matters of emergency systems development. In the summer of 1998 the project leaders of RODOS, WSPEEDI and ARAC met at FZK and agreed to join in a triangular collaboration on the development and demonstration of an emergency information exchange protocol. JAERI and FZK are engaged in developing a formal cooperation agreement. The purpose of this project is to evaluate the prototype information protocol application for technical feasibility and mutual benefit through simulated (real) event; quick exchange of atmospheric modeling products and environmental data during emergencies, distribution of predicted results to other countries having no prediction capabilities, and utilization of the link for collaborative studies.

  18. Fluidized bed heat exchanger utilizing angularly extending heat exchange tubes

    DOEpatents

    Talmud, Fred M.; Garcia-Mallol, Juan-Antonio

    1980-01-01

    A fluidized bed heat exchanger in which air is passed through a bed of particulate material containing fuel disposed in a housing. A steam/water natural circulation system is provided and includes a steam drum disposed adjacent the fluidized bed and a series of tubes connected at one end to the steam drum. A portion of the tubes are connected to a water drum and in the path of the air and the gaseous products of combustion exiting from the bed. Another portion of the tubes pass through the bed and extend at an angle to the upper surface of the bed.

  19. Diving into Real World Challenges

    ERIC Educational Resources Information Center

    Saldana, Matt; Rodden, Leslie

    2012-01-01

    In this article, the authors discuss how educators can engage students in real world learning using their academic knowledge and technical skills. They describe how school districts have discovered that the world of robotics can help students use technical skills to solve simulated problems found in the real world, while understanding the…

  20. Outsourcing real estate lease administration.

    PubMed

    Kardel, S

    1996-09-01

    Real estate lease administration is becoming increasingly important to healthcare organizations; however, not all organizations possess the in-house expertise to carry out this specialized function. For such organizations, outsourcing lease administration may be a more efficient way to manage their real estate portfolios and possibly improve their bottom lines.

  1. Real Life and the Classroom

    ERIC Educational Resources Information Center

    Van Praagh, Shauna

    2013-01-01

    The choices teachers make about both form and content in designing their courses shape students' perceptions of the connection between "real life" and the "classroom." The choice to begin a first-year law course with stories told by residential school survivors provides an example of how to bring "real life" into the…

  2. Tear exchange and contact lenses: a review.

    PubMed

    Muntz, Alex; Subbaraman, Lakshman N; Sorbara, Luigina; Jones, Lyndon

    2015-01-01

    Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses.

  3. Tear exchange and contact lenses: A review

    PubMed Central

    Muntz, Alex; Subbaraman, Lakshman N.; Sorbara, Luigina; Jones, Lyndon

    2015-01-01

    Tear exchange beneath a contact lens facilitates ongoing fluid replenishment between the ocular surface and the lens. This exchange is considerably lower during the wear of soft lenses compared with rigid lenses. As a result, the accumulation of tear film debris and metabolic by-products between the cornea and a soft contact lens increases, potentially leading to complications. Lens design innovations have been proposed, but no substantial improvement in soft lens tear exchange has been reported. Researchers have determined post-lens tear exchange using several methods, notably fluorophotometry. However, due to technological limitations, little remains known about tear hydrodynamics around the lens and, to-date, true tear exchange with contact lenses has not been shown. Further knowledge regarding tear exchange could be vital in aiding better contact lens design, with the prospect of alleviating certain adverse ocular responses. This article reviews the literature to-date on the significance, implications and measurement of tear exchange with contact lenses. PMID:25575892

  4. A Real Shooting Star

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Click on the image for movie of A Real Shooting Star

    This artist's animation illustrates a star flying through our galaxy at supersonic speeds, leaving a 13-light-year-long trail of glowing material in its wake. The star, named Mira (pronounced my-rah) after the latin word for 'wonderful,' sheds material that will be recycled into new stars, planets and possibly even life. NASA's Galaxy Evolution Explorer discovered the long trail of material behind Mira during its survey of the entire sky in ultraviolet light.

    The animation begins by showing a close-up of Mira -- a red-giant star near the end of its life. Red giants are red in color and extremely bloated; for example, if a red giant were to replace our sun, it would engulf everything out to the orbit of Mars. They constantly blow off gas and dust in the form of stellar winds, supplying the galaxy with molecules, such as oxygen and carbon, that will make their way into new solar systems. Our sun will mature into a red giant in about 5 billion years.

    As the animation pulls out, we can see the enormous trail of material deposited behind Mira as it hurls along between the stars. Like a boat traveling through water, a bow shock, or build up of gas, forms ahead of the star in the direction of its motion. Gas in the bow shock is heated and then mixes with the cool hydrogen gas in the wind that is blowing off Mira. This heated hydrogen gas then flows around behind the star, forming a turbulent wake.

    Why does the trailing hydrogen gas glow in ultraviolet light? When it is heated, it transitions into a higher-energy state, which then loses energy by emitting ultraviolet light - a process known as fluorescence.

    Finally, the artist's rendering gives way to the actual ultraviolet image taken by the Galaxy Evolution Explorer

    Mira is located 350 light-years from Earth in the constellation Cetus, otherwise known as the whale. Coincidentally, Mira

  5. Three-Dimensional Numerical Analysis of Laminar Heat Exchanger with Respect to Fin Shape and Fan Performance

    NASA Astrophysics Data System (ADS)

    Park, S. M.; Kim, J. Y.; Seol, S. S.; Lee, D. J.; Lee, M. C.

    2010-06-01

    The performances of the fin-and-tube heat exchangers with wavy or plain fins were numerically investigated using a commercial code based on the finite volume method implementing SIMPLE algorithm. The relations among the heat transfer performance, pressure and the fin shape were taken into consideration with the performance characteristic of the fan installed in the real heat exchanger. Generally, a heat exchanger with wavy fins shows better performance than that with plain fins under the same air flow rate. However, the performance of a heat exchanger was mainly affected by the performance characteristics of the installed fans. In case that a fan whose air flow rate remarkably changes by the minor pressure variation, the performance characteristic of the fan was much more important than the fin shape with respect to heat transfer rate. This is attributed to the fact that the air flow rates of fans were varied with the pressure loss of the heat exchanger.

  6. PREDICTION OF TOTAL DISSOLVED GAS EXCHANGE AT HYDROPOWER DAMS

    SciTech Connect

    Hadjerioua, Boualem; Pasha, MD Fayzul K; Stewart, Kevin M; Bender, Merlynn; Schneider, Michael L.

    2012-07-01

    Total dissolved gas (TDG) supersaturation in waters released at hydropower dams can cause gas bubble trauma in fisheries resulting in physical injuries and eyeball protrusion that can lead to mortality. Elevated TDG pressures in hydropower releases are generally caused by the entrainment of air in spillway releases and the subsequent exchange of atmospheric gasses into solution during passage through the stilling basin. The network of dams throughout the Columbia River Basin (CRB) are managed for irrigation, hydropower production, flood control, navigation, and fish passage that frequently result in both voluntary and involuntary spillway releases. These dam operations are constrained by state and federal water quality standards for TDG saturation which balance the benefits of spillway operations designed for Endangered Species Act (ESA)-listed fisheries versus the degradation to water quality as defined by TDG saturation. In the 1970s, the United States Environmental Protection Agency (USEPA), under the federal Clean Water Act (Section 303(d)), established a criterion not to exceed the TDG saturation level of 110% in order to protect freshwater and marine aquatic life. The states of Washington and Oregon have adopted special water quality standards for TDG saturation in the tailrace and forebays of hydropower facilities on the Columbia and Snake Rivers where spillway operations support fish passage objectives. The physical processes that affect TDG exchange at hydropower facilities have been studied throughout the CRB in site-specific studies and routine water quality monitoring programs. These data have been used to quantify the relationship between project operations, structural properties, and TDG exchange. These data have also been used to develop predictive models of TDG exchange to support real-time TDG management decisions. These empirically based predictive models have been developed for specific projects and account for both the fate of spillway and

  7. Ion exchange purification of scandium

    DOEpatents

    Herchenroeder, Laurie A.; Burkholder, Harvey R.

    1990-10-23

    An improvement in purification of scandium through ion exchange chromatography is disclosed in which the oxidation potential of the eluting solution is altered by the addition of potassium chlorate or ammonium chloride so that removal of contaminants is encouraged. The temperature, pH and concentration of the eluent HEDTA are controlled in order to maintain the scandium in the column while minimizing dilution of the scandium band. Recovery of scandium is improved by pumping dilute scandium over the column prior to stripping the scandium and precipitation. This eliminates the HEDTA ion and other monovalent cations contaminating the scandium band. This method maximizes recovery of scandium while maintaining purity.

  8. Ion exchange purification of scandium

    DOEpatents

    Herchenroeder, L.A.; Burkholder, H.R.

    1990-10-23

    An improvement in purification of scandium through ion exchange chromatography is disclosed in which the oxidation potential of the eluting solution is altered by the addition of potassium chlorate or ammonium chloride so that removal of contaminants is encouraged. The temperature, pH and concentration of the eluent HEDTA are controlled in order to maintain the scandium in the column while minimizing dilution of the scandium band. Recovery of scandium is improved by pumping dilute scandium over the column prior to stripping the scandium and precipitation. This eliminates the HEDTA ion and other monovalent cations contaminating the scandium band. This method maximizes recovery of scandium while maintaining purity. 2 figs.

  9. Random exchange interaction effects on the phase transitions in frustrated classical Heisenberg model

    SciTech Connect

    Li, W. C.; Song, X.; Feng, J. J.; Zeng, M.; Gao, X. S.; Qin, M. H.; Jia, X. T.

    2015-07-07

    In this work, the effects of the random exchange interaction on the phase transitions and phase diagrams of classical frustrated Heisenberg model are investigated by Monte Carlo simulation in order to simulate the chemical doping effect in real materials. It is observed that the antiferromagnetic transitions shift toward low temperature with the increasing magnitude of the random exchange interaction, which can be qualitatively understood from the competitions among local spin states. This study is related to the magnetic properties in the doped iron-based superconductors.

  10. Cooperative ring exchange and quantum melting of vortex lattices in atomic Bose-Einstein condensates

    SciTech Connect

    Ghosh, Tarun Kanti; Baskaran, G.

    2004-02-01

    Cooperative ring exchange is suggested as a mechanism of quantum melting of vortex lattices in a rapidly rotating quasi-two-dimensional atomic Bose-Einstein condensate (BEC). Using an approach pioneered by Kivelson et al. [Phys. Rev. Lett. 56, 873 (1986)] for the fractional quantized Hall effect, we calculate the condition for quantum melting instability by considering large-correlated ring exchanges in a two-dimensional Wigner crystal of vortices in a strong 'pseudomagnetic field' generated by the background superfluid Bose particles. BEC may be profitably used to address issues of quantum melting of a pristine Wigner solid devoid of complications of real solids.

  11. Analytical Performance of a Multiplex Real-Time PCR Assay Using TaqMan Probes for Quantification of Trypanosoma cruzi Satellite DNA in Blood Samples

    PubMed Central

    Abate, Teresa; Cayo, Nelly M.; Parrado, Rudy; Bello, Zoraida Diaz; Velazquez, Elsa; Muñoz-Calderon, Arturo; Juiz, Natalia A.; Basile, Joaquín; Garcia, Lineth; Riarte, Adelina; Nasser, Julio R.; Ocampo, Susana B.; Yadon, Zaida E.; Torrico, Faustino; de Noya, Belkisyole Alarcón; Ribeiro, Isabela; Schijman, Alejandro G.

    2013-01-01

    Background The analytical validation of sensitive, accurate and standardized Real-Time PCR methods for Trypanosoma cruzi quantification is crucial to provide a reliable laboratory tool for diagnosis of recent infections as well as for monitoring treatment efficacy. Methods/Principal Findings We have standardized and validated a multiplex Real-Time quantitative PCR assay (qPCR) based on TaqMan technology, aiming to quantify T. cruzi satellite DNA as well as an internal amplification control (IAC) in a single-tube reaction. IAC amplification allows rule out false negative PCR results due to inhibitory substances or loss of DNA during sample processing. The assay has a limit of detection (LOD) of 0.70 parasite equivalents/mL and a limit of quantification (LOQ) of 1.53 parasite equivalents/mL starting from non-boiled Guanidine EDTA blood spiked with T. cruzi CL-Brener stock. The method was evaluated with blood samples collected from Chagas disease patients experiencing different clinical stages and epidemiological scenarios: 1- Sixteen Venezuelan patients from an outbreak of oral transmission, 2- Sixty three Bolivian patients suffering chronic Chagas disease, 3- Thirty four Argentinean cases with chronic Chagas disease, 4- Twenty seven newborns to seropositive mothers, 5- A seronegative receptor who got infected after transplantation with a cadaveric kidney explanted from an infected subject. Conclusions/Significance The performing parameters of this assay encourage its application to early assessment of T. cruzi infection in cases in which serological methods are not informative, such as recent infections by oral contamination or congenital transmission or after transplantation with organs from seropositive donors, as well as for monitoring Chagas disease patients under etiological treatment. PMID:23350002

  12. 31 CFR 515.325 - National securities exchange.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false National securities exchange. 515.325... Definitions § 515.325 National securities exchange. The term national securities exchange shall mean an exchange registered as a national securities exchange under section 6 of the Securities Exchange Act...

  13. 31 CFR 515.325 - National securities exchange.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false National securities exchange. 515.325... Definitions § 515.325 National securities exchange. The term national securities exchange shall mean an exchange registered as a national securities exchange under section 6 of the Securities Exchange Act...

  14. 31 CFR 515.325 - National securities exchange.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false National securities exchange. 515.325... Definitions § 515.325 National securities exchange. The term national securities exchange shall mean an exchange registered as a national securities exchange under section 6 of the Securities Exchange Act...

  15. 31 CFR 500.325 - National securities exchange.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false National securities exchange. 500.325... Definitions § 500.325 National securities exchange. The term national securities exchange shall mean an exchange registered as a national securities exchange under section 6 of the Securities Exchange Act...

  16. 31 CFR 515.325 - National securities exchange.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 31 Money and Finance:Treasury 3 2012-07-01 2012-07-01 false National securities exchange. 515.325... Definitions § 515.325 National securities exchange. The term national securities exchange shall mean an exchange registered as a national securities exchange under section 6 of the Securities Exchange Act...

  17. 31 CFR 515.325 - National securities exchange.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false National securities exchange. 515.325... Definitions § 515.325 National securities exchange. The term national securities exchange shall mean an exchange registered as a national securities exchange under section 6 of the Securities Exchange Act...

  18. Inorganic ion exchangers for nuclear waste remediation

    SciTech Connect

    Clearfield, A.; Bortun, A.; Bortun, L.; Behrens, E.

    1997-10-01

    The objective of this work is to provide a broad spectrum of inorganic ion exchangers that can be used for a range of applications and separations involving remediation of groundwater and tank wastes. The authors intend to scale-up the most promising exchangers, through partnership with AlliedSignal Inc., to provide samples for testing at various DOE sites. While much of the focus is on exchangers for removal of Cs{sup +} and Sr{sup 2+} from highly alkaline tank wastes, especially at Hanford, the authors have also synthesized exchangers for acid wastes, alkaline wastes, groundwater, and mercury, cobalt, and chromium removal. These exchangers are now available for use at DOE sites. Many of the ion exchangers described here are new, and others are improved versions of previously known exchangers. They are generally one of three types: (1) layered compounds, (2) framework or tunnel compounds, and (3) amorphous exchangers in which a gel exchanger is used to bind a fine powder into a bead for column use. Most of these exchangers can be regenerated and used again.

  19. Testing and analysis of immersed heat exchangers

    SciTech Connect

    Farrington, R.B.; Bingham, C.E.

    1986-08-01

    The objectives were to determine the performance of four immersed, ''supply-side'' heat exchangers used in solar domestic-hot-water systems; to examine the effects of flow rate, temperature difference, and coil configuration on performance; and to develop a simple model to predict the performance of immersed heat exchangers. We tested four immersed heat exchangers: a smooth coil, a finned spiral, a single-wall bayonet, and a double-wall bayonet. We developed two analyticl models and a simple finite difference model. We experimentally verified that the performance of these heat exchangers depends on the flow rate through them; we also showed that the temperature difference between the heat exchanger's inlet and the storage tank can strongly affect a heat exchanger's performance. We also compared the effects of the heat exchanger's configuration and correlated Nusselt and Rayleigh numbers for each heat exchanger tested. The smooth coil had a higher effectiveness than the others, while the double-wall bayonet had a very low effectiveness. We still do not know the long-term effectiveness of heat exchangers regarding scale accumulation, nor do we know the effects of very low flow rates on a heat exchanger's performance.

  20. Orbital Propagation of Momentum Exchange Tether Systems

    NASA Technical Reports Server (NTRS)

    Westerhoff, John

    2002-01-01

    An advanced concept in in-space transportation currently being studied is the Momentum-Exchange/Electrodynamic Reboost Tether System (MXER). The system acts as a large momentum wheel, imparting a Av to a payload in low earth orbit (LEO) at the expense of its own orbital energy. After throwing a payload, the system reboosts itself using an electrodynamic tether to push against Earth's magnetic field and brings itself back up to an operational orbit to prepare for the next payload. The ability to reboost itself allows for continued reuse of the system without the expenditure of propellants. Considering the cost of lifting propellant from the ,ground to LEO to do the same Av boost at $10000 per pound, the system cuts the launch cost of the payload dramatically, and subsequently, the MXER system pays for itself after a small number of missions.1 One of the technical hurdles to be overcome with the MXER concept is the rendezvous maneuver. The rendezvous window for the capture of the payload is on the order of a few seconds, as opposed to traditional docking maneuvers, which can take as long ets necessary to complete a precise docking. The payload, therefore, must be able to match its orbit to meet up with the capture device on the end of the tether at a specific time and location in the future. In order to be able to determine that location, the MXER system must be numerically propagated forward in time to predict where the capture device will be at that instant. It should be kept in mind that the propagation computation must be done faster than real-time. This study focuses on the efforts to find and/or build the tools necessary to numerically propagate the motion of the MXER system as accurately as possible.

  1. OPEN DATA EXCHANGE IN SUPPORT OF CTBT RESEARCH

    NASA Astrophysics Data System (ADS)

    Willemann, R. J.; Simpson, D. W.; Suarez, G.; Ahern, T. K.

    2009-12-01

    Openly exchanged seismological data contribute to research and monitoring related to the CTBT and complement the more formally structured and restricted data procedures of the International Monitoring System (IMS). In addition to providing an increasingly rich source of data for fundamental research programs and monitoring, the open exchange of data encourages international and multi-disciplinary collaboration and leads to improvements in data quality and network practices. The IRIS Consortium and its Members commit to its mission to “promote exchange of geophysical data and knowledge, through use of standards for network operations, data formats, and exchange protocols, and through pursuing policies of free and unrestricted data access”. Data collected through IRIS programs as supported by the US National Science Foundation are archived at the IRIS Data Management Center (DMC) from which they are freely and openly available to researchers and the public. Continuous data from the IRIS/USGS Global Seismographic Network and the EarthScope Transportable Array are available in real-time. Investigators using portable PASSCAL and the EarthScope Flexible Array equipment can request a two-year proprietary period, following which all data must be archived at the DMC and made openly available. In addition to data from IRIS programs, the DMC archives and distributes data from many networks affiliated with the International Federation of Digital Seismographic Networks (FDSN), other national networks, and regional networks in the U.S.A. Networked data services provide access to the archives of additional data centers worldwide. Data exchange with the USGS National Earthquake Information Center, regional networks in the U.S. and international mission agencies contributes to global and national earthquake monitoring. All of the data in the DMC can be accessed with a common set of tools, providing easy access to waveforms from thousands of sensors in hundreds of networks

  2. Real-time flutter identification

    NASA Technical Reports Server (NTRS)

    Roy, R.; Walker, R.

    1985-01-01

    The techniques and a FORTRAN 77 MOdal Parameter IDentification (MOPID) computer program developed for identification of the frequencies and damping ratios of multiple flutter modes in real time are documented. Physically meaningful model parameterization was combined with state of the art recursive identification techniques and applied to the problem of real time flutter mode monitoring. The performance of the algorithm in terms of convergence speed and parameter estimation error is demonstrated for several simulated data cases, and the results of actual flight data analysis from two different vehicles are presented. It is indicated that the algorithm is capable of real time monitoring of aircraft flutter characteristics with a high degree of reliability.

  3. Real-time GPS Ionospheric TEC Estimation over South Korea

    NASA Astrophysics Data System (ADS)

    Choi, Byung-Kyu; Yoo, Sung-Moon; Roh, Kyoung-Min; Lee, Sang-Jeong

    2013-09-01

    Ionosphere is one of the largest error sources when the navigational signals produced by Global Positioning System (GPS) satellites are transmitted. Therefore it is very important to estimate total electron contents (TEC) in ionosphere precisely for navigation, precise positioning and some other applications. When we provide ionospheric TEC values in real-time, its application can be expanded to other areas. In this study we have used data obtained from nine Global Navigation Satellite System (GNSS) reference stations which have been operated by Korea Astronomy and Space Science Institute (KASI) to detect ionospheric TEC over South Korea in real-time. We performed data processing that covers converting 1Hz raw data delivered from GNSS reference stations to Receiver INdependent Exchange (RINEX) format files at intervals of 5 minutes. We also analyzed the elevation angles of GPS satellites, vertical TEC (VTEC) values and their changes.

  4. Fluorescence based real time monitoring of fouling in process chromatography

    PubMed Central

    Pathak, Mili; Lintern, Katherine; Chopda, Viki; Bracewell, Daniel G.; Rathore, Anurag S.

    2017-01-01

    A real time monitoring of fouling in liquid chromatography has been presented. The versatility of the approach has been proven by successful implementation in three case studies with an error <1%. The first application demonstrates the monitoring of protein A ligand density and foulant concentration for assessing performance of protein A chromatography resin during purification of monoclonal antibodies. The observations have been supported from LC-MS/MS studies that were independently performed. The second application involves monitoring of foulant deposition during multimode cation exchange chromatography based purification of human serum albumin. Finally, in the third application, monitoring of foulants during multimodal hydrophobic interaction chromatography of recombinant human granulocyte colony stimulating factor is demonstrated. In all three cases, it is observed that the fluorescence intensity consistently increases with resin reuse as more foulants are deposited over time. The proposed approach can be readily used for real time monitoring of fouling and process control. PMID:28358349

  5. Improved ceramic heat exchange material

    NASA Technical Reports Server (NTRS)

    Mccollister, H. L.

    1977-01-01

    Improved corrosion resistant ceramic materials that are suitable for use as regenerative heat exchangers for vehicular gas turbines is reported. Two glass-ceramic materials, C-144 and C-145, have superior durability towards sulfuric acid and sodium sulfate compared to lithium aluminosilicate (LAS) Corning heat exchange material 9455. Material C-144 is a leached LAS material whose major crystalline phase is silica keatite plus mullite, and C-145 is a LAS keatite solid solution (S.S.) material. In comparison to material 9455, material C-144 is two orders of magnitude better in dimensional stability to sulfuric acid at 300 C, and one order of magnitude better in stability to sodium sulfate at 1000 C. Material C-145 is initially two times better in stability to sulfuric acid, and about one order of magnitude better in stability to sodium sulfate. Both C-144 and C-145 have less than 300 ppm delta L/L thermal expansion from ambient to 1000 C, and good dimensional stability of less than approximately 100 ppm delta L/L after exposure to 1000 C for 100 hours. The glass-ceramic fabrication process produced a hexagonal honeycomb matrix having an 85% open frontal area, 50 micrometer wall thickness, and less than 5% porosity.

  6. Convection and interfacial mass exchange

    NASA Astrophysics Data System (ADS)

    Colinet, P.; Legros, J. C.; Dauby, P. C.; Lebon, G.; Bestehorn, M.; Stephan, P.; Tadrist, L.; Cerisier, P.; Poncelet, D.; Barremaecker, L.

    2005-10-01

    Mass-exchange through fluid interfaces is ubiquitous in many natural and industrial processes. Yet even basic phase-change processes such as evaporation of a pure liquid are not fully understood, in particular when coupled with fluid motions in the vicinity of the phase-change interface, or with microscopic physical phenomena in the vicinity of a triple line (where the interface meets a solid). Nowadays, many industries recognise that this lack of fundamental knowledge is hindering the optimisation of existing processes. Their modelling tools are too dependent on empirical correlations with a limited - and often unknown - range of applicability. In addition to the intrinsic multiscale nature of the phenomena involved in typical industrial processes linked to interfacial mass exchange, their study is highly multi-disciplinary, involving tools and techniques belonging to physical chemistry, chemical engineering, fluid dynamics, non-linear physics, non-equilibrium thermodynamics, chemistry and statistical physics. From the experimental point of view, microgravity offers a unique environment to obtain valuable data on phase-change processes, greatly reducing the influence of body forces and allowing the detailed and accurate study of interfacial dynamics. In turn, such improved understanding leads to optimisation of industrial processes and devices involving phase-change, both for space and ground applications.

  7. Seasonality of Arctic Mediterranean Exchanges

    NASA Astrophysics Data System (ADS)

    Rieper, Christoph; Quadfasel, Detlef

    2015-04-01

    The Arctic Mediterranean communicates through a number of passages with the Atlantic and the Pacific Oceans. Most of the volume exchange happens at the Greenland-Scotland-Ridge: warm and saline Atlantic Water flows in at the surface, cold, dense Overflow Water flows back at the bottom and fresh and cold Polar Water flows out along the East Greenland coast. All surface inflows show a seasonal signal whereas only the outflow through the Faroe Bank Channel exhibits significant seasonality. Here we present a quantification of the seasonal cycle of the exchanges across the Greenland-Scotland ridge based on volume estimates of the in- and outflows within the last 20 years (ADCP and altimetry). Our approach is comparatistic: we compare different properties of the seasonal cycle like the strength or the phase between the different in- and outflows. On the seasonal time scale the in- and outflows across the Greenland-Scotland-Ridge are not balanced. The net flux thus has to be balanced by the other passages on the Canadian Archipelago, Bering Strait as well as runoff from land.

  8. Exchange of astronomy teaching experiences

    NASA Astrophysics Data System (ADS)

    Ros, Rosa M.

    The Working Group of the European Association for Astronomy Education responsible for Teacher Training organises an annual Summer School for teachers under expert guidance. For a week the teachers participating can exchange experiences, increase their knowledge and discuss different ideas and perspectives. In general, the instructors are professional astronomers, professors and teachers from different countries. The papers presented offer very practical activities, paying special attention to didactic aspects, and take the form of general lectures to all 40 participants and workshops to reduced groups of 20 participants. There are also day and night observations, without expensive equipment or complicated procedures, that are easy to set up and based on topics that it is possible to use in the classroom. The Summer Schools promote a scientific astronomical education at all levels of astronomy teaching, reinforce the link between professional astronomers and teachers with experience of teaching astronomy, allow debates among the participants on their pedagogical activities already carried out in their own classroom and help them to organise activities outside it. Astronomy teachers need special training, access to specific research, to new educational materials and methods and the opportunity to exchange experiences. All these things are provided by the Summer School.

  9. "He Hasn't Got the Real Toolkit!" Young Children's Reasoning about Real/Not-Real Status

    ERIC Educational Resources Information Center

    Bunce, Louise; Harris, Margaret

    2013-01-01

    During the preschool years, children develop an understanding of 2 types of real/not-real distinctions: ontological status and authenticity (Bunce & Harris, 2008). Two studies compared 3- to 5-year-old children's real/not-real judgments and justifications for 3 types of contrast involving a real entity and either a fictional character, a child…

  10. 26 CFR 1.1033(g)-1 - Condemnation of real property held for productive use in trade or business or for investment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... productive use in trade or business or for investment. 1.1033(g)-1 Section 1.1033(g)-1 Internal Revenue... Nontaxable Exchanges § 1.1033(g)-1 Condemnation of real property held for productive use in trade or business... advertising displays as real property—(1) In general. Under section 1033(g)(3) of the Code, a taxpayer...

  11. DHE (downhole heat exchangers). [Downhole Heat Exchangers (DHE)

    SciTech Connect

    Culver, G.

    1990-11-01

    The use of downhole heat exchangers (DHE) for residential or commercial space and domestic water heating and other applications has several desirable features. Systems are nearly or completely passive -- that is, no or very little geothermal water or steam is produced from the well either reducing or completely eliminating surface environmental concerns and the need for disposal systems or injection wells. Initial cost of pumps and installation are eliminated or reduced along with pumping power costs and maintenance costs associated with pumping often corrosive geothermal fluids. Many residential and small commercial systems do not require circulating pumps because the density difference in the incoming and outgoing sides of the loop are sufficient to overcome circulating friction losses in the entire system. The major disadvantage of DHEs is their dependence on natural heat flow. In areas where geological conditions provide high permeability and a natural hydraulic gradient, DHEs can provide a substantial quantity of heat. A single 500-ft (152 m) well in Klamath Falls, Oregon, supplies over one megawatt thermal and output is apparently limited by the surface area of pipe that can be installed in the well bore. In contrast, DHEs used in conjunction with heat pumps may supply less than 8 KW from a well of similar depth. Here output is limited by conductive heat flow with perhaps a small contribution from convection near the well bore. The highest capacity DHE reported to date, in Turkey, supplies 6 MW thermal from an 820-ft (250 m) well. There were two main goals for this project. The first was to gather, disseminate and exchange internationally information on DHES. The second was to perform experiments that would provide insight into well bore/aquifer interaction and thereby provide more information on which to base DHE designs. 27 refs., 31 figs., 3 tabs.

  12. Quantifying randomness in real networks

    PubMed Central

    Orsini, Chiara; Dankulov, Marija M.; Colomer-de-Simón, Pol; Jamakovic, Almerima; Mahadevan, Priya; Vahdat, Amin; Bassler, Kevin E.; Toroczkai, Zoltán; Boguñá, Marián; Caldarelli, Guido; Fortunato, Santo; Krioukov, Dmitri

    2015-01-01

    Represented as graphs, real networks are intricate combinations of order and disorder. Fixing some of the structural properties of network models to their values observed in real networks, many other properties appear as statistical consequences of these fixed observables, plus randomness in other respects. Here we employ the dk-series, a complete set of basic characteristics of the network structure, to study the statistical dependencies between different network properties. We consider six real networks—the Internet, US airport network, human protein interactions, technosocial web of trust, English word network, and an fMRI map of the human brain—and find that many important local and global structural properties of these networks are closely reproduced by dk-random graphs whose degree distributions, degree correlations and clustering are as in the corresponding real network. We discuss important conceptual, methodological, and practical implications of this evaluation of network randomness, and release software to generate dk-random graphs. PMID:26482121

  13. Quantifying randomness in real networks

    NASA Astrophysics Data System (ADS)

    Orsini, Chiara; Dankulov, Marija M.; Colomer-de-Simón, Pol; Jamakovic, Almerima; Mahadevan, Priya; Vahdat, Amin; Bassler, Kevin E.; Toroczkai, Zoltán; Boguñá, Marián; Caldarelli, Guido; Fortunato, Santo; Krioukov, Dmitri

    2015-10-01

    Represented as graphs, real networks are intricate combinations of order and disorder. Fixing some of the structural properties of network models to their values observed in real networks, many other properties appear as statistical consequences of these fixed observables, plus randomness in other respects. Here we employ the dk-series, a complete set of basic characteristics of the network structure, to study the statistical dependencies between different network properties. We consider six real networks--the Internet, US airport network, human protein interactions, technosocial web of trust, English word network, and an fMRI map of the human brain--and find that many important local and global structural properties of these networks are closely reproduced by dk-random graphs whose degree distributions, degree correlations and clustering are as in the corresponding real network. We discuss important conceptual, methodological, and practical implications of this evaluation of network randomness, and release software to generate dk-random graphs.

  14. Real estate strategies for 2005.

    PubMed

    Dunbar, Donald R

    2005-05-01

    Today's healthcare real estate strategies involve: assessing and prioritizing capital availability for building projects, carefully planning and implementing the process for the project Making beneficial decisions regarding facility management and maintenance.

  15. Real and Hybrid Atomic Orbitals.

    ERIC Educational Resources Information Center

    Cook, D. B.; Fowler, P. W.

    1981-01-01

    Demonstrates that the Schrodinger equation for the hydrogenlike atom separates in both spheroconal and prolate spheroidal coordinates and that these separations provide a sound theoretical basis for the real and hybrid atomic orbitals. (Author/SK)

  16. Real-time software receiver

    NASA Technical Reports Server (NTRS)

    Ledvina, Brent M. (Inventor); Psiaki, Mark L. (Inventor); Powell, Steven P. (Inventor); Kintner, Jr., Paul M. (Inventor)

    2006-01-01

    A real-time software receiver that executes on a general purpose processor. The software receiver includes data acquisition and correlator modules that perform, in place of hardware correlation, baseband mixing and PRN code correlation using bit-wise parallelism.

  17. Real-time software receiver

    NASA Technical Reports Server (NTRS)

    Ledvina, Brent M. (Inventor); Psiaki, Mark L. (Inventor); Powell, Steven P. (Inventor); Kintner, Jr., Paul M. (Inventor)

    2007-01-01

    A real-time software receiver that executes on a general purpose processor. The software receiver includes data acquisition and correlator modules that perform, in place of hardware correlation, baseband mixing and PRN code correlation using bit-wise parallelism.

  18. The real-world navigator

    NASA Technical Reports Server (NTRS)

    Balabanovic, Marko; Becker, Craig; Morse, Sarah K.; Nourbakhsh, Illah R.

    1994-01-01

    The success of every mobile robot application hinges on the ability to navigate robustly in the real world. The problem of robust navigation is separable from the challenges faced by any particular robot application. We offer the Real-World Navigator as a solution architecture that includes a path planner, a map-based localizer, and a motion control loop that combines reactive avoidance modules with deliberate goal-based motion. Our architecture achieves a high degree of reliability by maintaining and reasoning about an explicit description of positional uncertainty. We provide two implementations of real-world robot systems that incorporate the Real-World Navigator. The Vagabond Project culminated in a robot that successfully navigated a portion of the Stanford University campus. The Scimmer project developed successful entries for the AIAA 1993 Robotics Competition, placing first in one of the two contests entered.

  19. Real Automation in the Field

    NASA Technical Reports Server (NTRS)

    Munoz, Cesar; Mayero, Micaela; Bushnell, Dennis M. (Technical Monitor)

    2001-01-01

    We provide a package of strategies for automation of non-linear arithmetic in PVS. In particular, we describe a simplication procedure for the field of real numbers and a strategy for cancellation of common terms.

  20. Quantifying randomness in real networks.

    PubMed

    Orsini, Chiara; Dankulov, Marija M; Colomer-de-Simón, Pol; Jamakovic, Almerima; Mahadevan, Priya; Vahdat, Amin; Bassler, Kevin E; Toroczkai, Zoltán; Boguñá, Marián; Caldarelli, Guido; Fortunato, Santo; Krioukov, Dmitri

    2015-10-20

    Represented as graphs, real networks are intricate combinations of order and disorder. Fixing some of the structural properties of network models to their values observed in real networks, many other properties appear as statistical consequences of these fixed observables, plus randomness in other respects. Here we employ the dk-series, a complete set of basic characteristics of the network structure, to study the statistical dependencies between different network properties. We consider six real networks--the Internet, US airport network, human protein interactions, technosocial web of trust, English word network, and an fMRI map of the human brain--and find that many important local and global structural properties of these networks are closely reproduced by dk-random graphs whose degree distributions, degree correlations and clustering are as in the corresponding real network. We discuss important conceptual, methodological, and practical implications of this evaluation of network randomness, and release software to generate dk-random graphs.

  1. Surface- vs Diffusion-Limited Mechanisms of Anion Exchange in CsPbBr3 Nanocrystal Cubes Revealed through Kinetic Studies.

    PubMed

    Koscher, Brent A; Bronstein, Noah D; Olshansky, Jacob H; Bekenstein, Yehonadav; Alivisatos, A Paul

    2016-09-21

    Ion-exchange transformations allow access to nanocrystalline materials with compositions that are inaccessible via direct synthetic routes. However, additional mechanistic insight into the processes that govern these reactions is needed. We present evidence for the presence of two distinct mechanisms of exchange during anion exchange in CsPbX3 nanocrystals (NCs), ranging in size from 6.5 to 11.5 nm, for transformations from CsPbBr3 to CsPbCl3 or CsPbI3. These NCs exhibit bright luminescence throughout the exchange, allowing their optical properties to be observed in real time, in situ. The iodine exchange presents surface-reaction-limited exchanges allowing all anionic sites within the NC to appear chemically identical, whereas the chlorine exchange presents diffusion-limited exchanges proceeding through a more complicated exchange mechanism. Our results represent the first steps toward developing a microkinetic description of the anion exchange, with implications not only for understanding the lead halide perovskites but also for nanoscale ion exchange in general.

  2. Slc26a6: a cardiac chloride–hydroxyl exchanger and predominant chloride–bicarbonate exchanger of the mouse heart

    PubMed Central

    Alvarez, Bernardo V; Kieller, Dawn M; Quon, Anita L; Markovich, Daniel; Casey, Joseph R

    2004-01-01

    Bicarbonate facilitate more than 50% of pH recovery in the acidotic myocardium, and have roles in cardiac hypertrophy and steady-state pH regulation. To determine which bicarbonate transporters are responsible for this activity, we measured the expression levels of all known HCO3−–anion exchange proteins in mouse heart, by quantitative real time RT-PCR. Bicarbonate–anion exchangers are members of either the SLC4A or the SLC26A gene families. In neonatal and adult myocardium, AE1 (Slc4a1), AE2 (Slc4a2), AE3 (Slc4a3) (AE3fl and AE3c variants), Slc26a3 and Slc26a6 were expressed. Adult hearts expressed Slc26a3 and Slc4a1–3 mRNAs at similar levels, while Slc26a6 mRNA was about seven-fold higher than AE3, which was more abundant than any other. Immunohistochemistry revealed that Slc26a6 and AE3 are present in the plasma membrane of ventricular myocytes. Slc26a6 expression levels were higher in ventricle than atrium, whereas AE3 was detected only in ventricle. Cl−–HCO3− and Cl−–OH− exchange activity of SLC26A6 and AE3 were investigated in transfected HEK293 cells, using intracellular fluorescence measurements of 2′,7′-bis (2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF), to monitor intracellular pH (pHi). Rates of pHi change were measured under HCO3−-containing (Cl−–HCO3−) or nominally HCO3−-free (Cl−–OH−) conditions. HCO3− fluxes were similar for cells expressing AE3fl, SLC26A6 or Slc26a3, suggesting that they have similar transport activity. However, only SLC26A6 and Slc26a3 functioned as Cl−–OH− exchangers. Activation of α-adrenergic receptors, which stimulates protein kinase C, inhibited SLC26A6 Cl−–HCO3− exchange activity. We conclude that Slc26a6 is the predominant Cl−–HCO3− and Cl−–OH− exchanger of the myocardium and that Slc26a6 is negatively regulated upon α-adrenergic stimulation. PMID:15498800

  3. The Perceived and Real Value of Health Information Exchange in Public Health Surveillance

    ERIC Educational Resources Information Center

    Dixon, Brian Edward

    2011-01-01

    Public health agencies protect the health and safety of populations. A key function of public health agencies is surveillance or the ongoing, systematic collection, analysis, interpretation, and dissemination of data about health-related events. Recent public health events, such as the H1N1 outbreak, have triggered increased funding for and…

  4. Real Time Monitoring of Temperature of a Micro Proton Exchange Membrane Fuel Cell

    PubMed Central

    Lee, Chi-Yuan; Lee, Shuo-Jen; Hu, Yuh-Chung; Shih, Wen-Pin; Fan, Wei-Yuan; Chuang, Chih-Wei

    2009-01-01

    Silicon micro-hole arrays (Si-MHA) were fabricated as a gas diffusion layer (GDL) in a micro fuel cell using the micro-electro-mechanical-systems (MEMS) fabrication technique. The resistance temperature detector (RTD) sensor was integrated with the GDL on a bipolar plate to measure the temperature inside the fuel cell. Experimental results demonstrate that temperature was generally linearly related to resistance and that accuracy and sensitivity were within 0.5 °C and 1.68×10−3/°C, respectively. The best experimental performance was 9.37 mW/cm2 at an H2/O2 dry gas flow rate of 30/30 SCCM. Fuel cell temperature during operation was 27 °C, as measured using thermocouples in contact with the backside of the electrode. Fuel cell operating temperature measured in situ was 30.5 °C. PMID:22573963

  5. Full Electric Control of Exchange Bias

    NASA Astrophysics Data System (ADS)

    Wu, S. M.; Cybart, Shane A.; Yi, D.; Parker, James M.; Ramesh, R.; Dynes, R. C.

    2013-02-01

    We report the creation of a multiferroic field effect device with a BiFeO3 (BFO) (antiferromagnetic-ferroelectric) gate dielectric and a La0.7Sr0.3MnO3 (LSMO) (ferromagnetic) conducting channel that exhibits direct, bipolar electrical control of exchange bias. We show that exchange bias is reversibly switched between two stable states with opposite exchange bias polarities upon ferroelectric poling of the BFO. No field cooling, temperature cycling, or additional applied magnetic or electric field beyond the initial BFO polarization is needed for this bipolar modulation effect. Based on these results and the current understanding of exchange bias, we propose a model to explain the control of exchange bias. In this model the coupled antiferromagnetic-ferroelectric order in BFO along with the modulation of interfacial exchange interactions due to ionic displacement of Fe3+ in BFO relative to Mn3+/4+ in LSMO cause bipolar modulation.

  6. Real Time Data System (RTDS)

    NASA Technical Reports Server (NTRS)

    Muratore, John F.

    1991-01-01

    Lessons learned from operational real time expert systems are examined. The basic system architecture is discussed. An expert system is any software that performs tasks to a standard that would normally require a human expert. An expert system implies knowledge contained in data rather than code. And an expert system implies the use of heuristics as well as algorithms. The 15 top lessons learned by the operation of a real time data system are presented.

  7. Real-time vision systems

    SciTech Connect

    Johnson, R.; Hernandez, J.E.; Lu, Shin-yee

    1994-11-15

    Many industrial and defence applications require an ability to make instantaneous decisions based on sensor input of a time varying process. Such systems are referred to as `real-time systems` because they process and act on data as it occurs in time. When a vision sensor is used in a real-time system, the processing demands can be quite substantial, with typical data rates of 10-20 million samples per second. A real-time Machine Vision Laboratory (MVL) was established in FY94 to extend our years of experience in developing computer vision algorithms to include the development and implementation of real-time vision systems. The laboratory is equipped with a variety of hardware components, including Datacube image acquisition and processing boards, a Sun workstation, and several different types of CCD cameras, including monochrome and color area cameras and analog and digital line-scan cameras. The equipment is reconfigurable for prototyping different applications. This facility has been used to support several programs at LLNL, including O Division`s Peacemaker and Deadeye Projects as well as the CRADA with the U.S. Textile Industry, CAFE (Computer Aided Fabric Inspection). To date, we have successfully demonstrated several real-time applications: bullet tracking, stereo tracking and ranging, and web inspection. This work has been documented in the ongoing development of a real-time software library.

  8. 15 CFR 806.8 - Real estate.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Real estate. 806.8 Section 806.8... ECONOMIC ANALYSIS, DEPARTMENT OF COMMERCE DIRECT INVESTMENT SURVEYS § 806.8 Real estate. Residential real..., is considered real estate held for personal use. Ownership of residential real estate by...

  9. Sparseness and Roughness of Foreign Exchange Rates

    NASA Astrophysics Data System (ADS)

    Vandewalle, N.; Ausloos, M.

    An accurate multiaffine analysis of 23 foreign currency exchange rates has been performed. The roughness exponent H1 which characterizes the excursion of the exchange rate has been numerically measured. The degree of intermittency C1 has been also estimated. In the (H1,C1) phase diagram, the currency exchange rates are dispersed in a wide region around the Brownian motion value (H1=0.5,C1=0) and have a significantly intermittent component (C1≠0).

  10. Electric Control of Exchange Bias Training

    NASA Astrophysics Data System (ADS)

    Echtenkamp, W.; Binek, Ch.

    2013-11-01

    Voltage-controlled exchange bias training and tunability are introduced. Isothermal voltage pulses are used to reverse the antiferromagnetic order parameter of magnetoelectric Cr2O3, and thus continuously tune the exchange bias of an adjacent CoPd film. Voltage-controlled exchange bias training is initialized by tuning the antiferromagnetic interface into a nonequilibrium state incommensurate with the underlying bulk. Interpretation of these hitherto unreported effects contributes to new understanding in electrically controlled magnetism.

  11. Apparent exchange rate mapping with diffusion MRI.

    PubMed

    Lasič, Samo; Nilsson, Markus; Lätt, Jimmy; Ståhlberg, Freddy; Topgaard, Daniel

    2011-08-01

    Water exchange through the cell membranes is an important feature of cells and tissues. The rate of exchange is determined by factors such as membrane lipid composition and organization, as well as the type and activity of aquaporins. A method for noninvasively estimating the rate of water exchange would be useful for characterizing pathological conditions, e.g., tumors, multiple sclerosis, and ischemic stroke, expected to be associated with a change of the membrane barrier properties. This study describes the filter exchange imaging method for determining the rate of water exchange between sites having different apparent diffusion coefficients. The method is based on the filter-exchange pulsed gradient spin-echo NMR spectroscopy experiment, which is here modified to be compatible with the constraints of clinical MR scanners. The data is analyzed using a model-free approach yielding maps of the apparent exchange rate, here being introduced in analogy with the concept of the apparent diffusion coefficient. Proof-of-principle experiments are performed on microimaging and whole-body clinical scanners using yeast suspension phantoms. The limitations and appropriate experimental conditions are examined. The results demonstrate that filter exchange imaging is a fast and reliable method for characterizing exchange, and that it has the potential to become a powerful diagnostic tool.

  12. Ion Exchange and Liquid Column Chromatography.

    ERIC Educational Resources Information Center

    Walton, Harold F.

    1980-01-01

    Emphasizes recent advances in principles and methodology in ion exchange and chromatography. Two tables list representative examples for inorganic ions and organic compounds. Cites 544 references. (CS)

  13. Adaptive Strategies in the Iterated Exchange Problem

    NASA Astrophysics Data System (ADS)

    Baraov, Arthur

    2011-03-01

    We argue for clear separation of the exchange problem from the exchange paradox to avoid confusion about the subject matter of these two distinct problems. The exchange problem in its current format belongs to the domain of optimal decision making—it doesn't make any sense as a game of competition. But it takes just a tiny modification in the statement of the problem to breathe new life into it and make it a practicable and meaningful game of competition. In this paper, we offer an explanation for paradoxical priors and discuss adaptive strategies for both the house and the player in the restated exchange problem.

  14. Entropy exchange for infinite-dimensional systems

    PubMed Central

    Duan, Zhoubo; Hou, Jinchuan

    2017-01-01

    In this paper the entropy exchange for channels and states in infinite-dimensional systems are defined and studied. It is shown that, this entropy exchange depends only on the given channel and the state. An explicit expression of the entropy exchange in terms of the state and the channel is proposed. The generalized Klein’s inequality, the subadditivity and the triangle inequality about the entropy including infinite entropy for the infinite-dimensional systems are established, and then, applied to compare the entropy exchange with the entropy change. PMID:28164995

  15. Energy recovery heat exchanger installation

    SciTech Connect

    Bradshaw, N.F.

    1983-08-16

    An installation is disclosed for energy recovery heat exchangers arranged to transfer heat into or out of air exhausted from an air handling system for paint spray booths. The system includes a collection chamber about which the intakes of a series of exhaust fans are arranged to draw exhaust air into an exhaust stack. Pairs of inclined wetted surface coil sets are mounted in the walls of the enclosures, each in communication with the intake of an exhaust fan so as to receive airflow of each exhaust fan. Each of the enclosures is provided with an access door to enable cleaning and other maintenance chores to be carried out on the coil sets and pivotally mounted blocking panels may be positioned to close off air flow across the coils and bypassing of the exhaust flow through the access doors in the event excessive overspray solids are present in the exhaust flow.

  16. Educational Exchanges Across the Equator

    NASA Astrophysics Data System (ADS)

    Norman, D. J.; Walker, C. E.; Smith, M.; Pompea, S. M.; Orellana, D.

    2003-12-01

    What is color? What is light? How can we use a spectrometer to help students understand the answers to these questions? Even half a world apart and between people of different languages and cultures, how to teach these ideas to students can be a lively subject for discussion. And it is! Aided by Internet 2-based videoconferencing, NOAO North and South have sponsored three teacher professional development videoconference workshops, dubbed ASTRO-Chile, linking teachers in Tucson, AZ, and La Serena, Chile. The teachers exchange methods and ideas about how to explain and demonstrate physical concepts, important to the study of astronomy, to students of various ages. The workshops are conducted in Spanish with four bilingual science teachers from the Tucson area discussing pedagogical approaches with their teaching counterparts in Chile. Demonstrations and project presentations, from both sites, are included as part of each workshop. This work is supported, in part, through funding from the NSF Astronomy and Astrophysics Postdoctoral Fellowship.

  17. Oxidizer heat exchanger component testing

    NASA Technical Reports Server (NTRS)

    Kmiec, T.; Kanic, P.

    1986-01-01

    As part of the RL10 Rocket Engine Product Improvement Program, Oxidizer Heat Exchanger (OHE) stages 1, 2, and 3 were designed and fabricated during late 1983 and early 1984. The purpose of the OHE is to provide gaseous oxygen to the propellant injector for stable engine operation at tank head idle and pumped idle operating modes. This report summarizes the OHE stages 1 and 3 rig testing, and includes the separation of the stage 1-and-2 assembly and the remanifolding of stage 1. The OHE performance analysis and analytical model modifications for both stages are also presented. The flow tests were accomplished during the time period from 9 October 1984 to 12 November 1984.

  18. The data of GDP and exchange rate used in the Balassa-Samuelson hypothesis.

    PubMed

    Wang, Weiguo; Xue, Jing; Du, Chonghua

    2016-12-01

    This article introduces the data of the log real GDP per capita ratio and the log real exchange rate which are used to revisit the Balassa-Samuelson Hypothesis. We acquired the data from IMF and World Bank database, and provide the name and source of the data. All data are openly accessible. Besides, we describe the value of data as well as the method to process the data which can also be found in "The Balassa-Samuelson Hypothesis in the developed and developing countries revisited" (Weiguo Wang, Jing Xue, Chonghua Du, 2016) [1].

  19. Model of Wikipedia growth based on information exchange via reciprocal arcs

    NASA Astrophysics Data System (ADS)

    Zlatić, V.; Štefančić, H.

    2011-03-01

    We show how reciprocal arcs significantly influence the structural organization of Wikipedias, online encyclopedias. It is shown that random addition of reciprocal arcs in the static network cannot explain the observed reciprocity of Wikipedias. A model of Wikipedia growth based on preferential attachment and on information exchange via reciprocal arcs is presented. An excellent agreement between in-degree distributions of our model and real Wikipedia networks is achieved without fitting the distributions, but by merely extracting a small number of model parameters from the measurement of real networks.

  20. Indian/atlantic Interocean Exchanges

    NASA Astrophysics Data System (ADS)

    Matano, R. P.; Beier, E. J.

    In this presentation we analyze the interocean exchanges between the Indian and the South Atlantic Oceans simulated in an global, eddy-permitting simulation. The analy- sis focuses in the Cape Basin, a region of the southeastern Atlantic limited to the north- west by the Walvis Ridge and to the south by the subtropical convergence. To quantify the relative importance of the different dynamical mechanisms involved in the intero- cean exchange we separated the climatological mean circulation from the transients. The analysis indicates that Agulhas eddies not only influence the transient fluxes but also to those associated with the mean circulation (eddy fluxes, for example, supply most of the energy of the Benguela Current). A distinct characteristic of the eddy variability within the Cape Basin is the co-existence of cyclonic and anticyclonic vor- tices in dipole structures that resemble the heton model of Hogg and Stommel (Deep Sea Research,1985). Anticyclones are surface intensified vortices that, in spite of their baroclinic structure, reach to deep layers. Cyclones, are bottom-intensified vortices with dominant barotropic structure that projects into the upper layer. The propaga- tion of cyclones and anticyclones is strongly affected by the bottom topography. Our analysis shows that the Walvis Ridge and the Vema Seamount block the passage of bottom-intensified cyclones and rectifies the trajectories of the upper-intensified anti- cyclones. Although most anticyclones are able to escape the basin the deep compen- sation generated by the ridge generates an energy loss of approximately 30%, and a rectification of the eddy trajectory to a more westward direction.

  1. Time scale defined by the fractal structure of the price fluctuations in foreign exchange markets

    NASA Astrophysics Data System (ADS)

    Kumagai, Yoshiaki

    2010-04-01

    In this contribution, a new time scale named C-fluctuation time is defined by price fluctuations observed at a given resolution. The intraday fractal structures and the relations of the three time scales: real time (physical time), tick time and C-fluctuation time, in foreign exchange markets are analyzed. The data set used is trading prices of foreign exchange rates; US dollar (USD)/Japanese yen (JPY), USD/Euro (EUR), and EUR/JPY. The accuracy of the data is one minute and data within a minute are recorded in order of transaction. The series of instantaneous velocity of C-fluctuation time flowing are exponentially distributed for small C when they are measured by real time and for tiny C when they are measured by tick time. When the market is volatile, for larger C, the series of instantaneous velocity are exponentially distributed.

  2. Enhanced Computational Toolbox Including Multiquantum Vibration-Translation (VT) & Vibration-Electronic (VE) Exchanges, Dissociation and Radiation Effects. Deliverable 4

    DTIC Science & Technology

    2011-04-30

    of flow parameters. PETTT, HPC, HPCMP, Real gas , dissociation, Radiation effects, multiquantum energy exchanges, Master equation, State-to-state...TRANSITIONS ON THE RELAXATION OF A N2 GAS FLOW BEHIND A SHOCK...42 APPENDIX D: STATE-SPECIFIC MODELING OF RADIATION IN REACTIVE NONEQUILIBRIUM GAS FLOWS

  3. 78 FR 62849 - Self-Regulatory Organizations; C2 Options Exchange, Incorporated; Notice of Filing and Immediate...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-22

    ... Effectiveness of a Proposed Rule Change Relating to Fees for the Complex Order Book Data Feed for C2 Listed...''), an affiliate of C2, to establish fees for the Complex Order Book (``COB'') Data Feed for C2 listed... a real-time feed that consists of data regarding the Exchange's Complex Order Book and...

  4. Trade balance instability and the optimal exchange rate regime: The case of OPEC countries

    SciTech Connect

    Aljerrah, M.A.

    1993-01-01

    The OPEC members have experienced wide fluctuations in their trade balances. This can be attributed to several factors: (1) heavy dependence of national income and export earnings on a single primary export-oil; (2) instability of price and world demand for oil; and (3) the exchange rate regime practiced in recent years. An exchange rate policy can be used to minimize the fluctuations in trade balance, given the changes in exchange rates of major international currencies. The purpose of this study is two fold; first, examine the effects of fluctuations in trade balance on the OPEC economies, and second, propose appropriate exchange rate regime for selected OPEC members. The study is divided into two parts. The first part demonstrates the impact of trade balance changes on national income and other macroeconomic variables using a Keynesian framework. The second part involves using conventional trade models to search for the appropriate exchange rate regime to minimize the fluctuations in trade balance of each selective country. The study's findings are: first, fluctuations in trade balances had negative effects on the economics of Algeria, Kuwait, Libya, Saudi Arabia, and the United Arab Emirates. Second, the current exchange rate regime of no sample country is optimal in minimizing trade balance fluctuations. Third, in contrast to expectations, U.S. dollar peg did not stabilize the trade balance of any OPEC member. Finally, the results show that the sample OPEC economies could have enjoyed faster - though with different degree - economic growth if they had pegged their currencies to the derived optimal exchange rate regime. These optimal exchange rate regimes are: the SDR for Algeria and the United Arab Emirates, the purchasing power parity for Libya and Saudi Arabia, and the real Yen for Kuwait.

  5. Risk management and market efficiency on the Midwest Independent System Operator electricity exchange

    NASA Astrophysics Data System (ADS)

    Jones, Kevin

    Midwest Independent Transmission System Operator, Inc. (MISO) is a non-profit regional transmission organization (RTO) that oversees electricity production and transmission across thirteen states and one Canadian province. MISO also operates an electronic exchange for buying and selling electricity for each of its five regional hubs. MISO oversees two types of markets. The forward market, which is referred to as the day-ahead (DA) market, allows market participants to place demand bids and supply offers on electricity to be delivered at a specified hour the following day. The equilibrium price, known as the locational marginal price (LMP), is determined by MISO after receiving sale offers and purchase bids from market participants. MISO also coordinates a spot market, which is known as the real-time (RT) market. Traders in the real-time market must submit bids and offers by thirty minutes prior to the hour for which the trade will be executed. After receiving purchase and sale offers for a given hour in the real time market, MISO then determines the LMP for that particular hour. The existence of the DA and RT markets allows producers and retailers to hedge against the large fluctuations that are common in electricity prices. Hedge ratios on the MISO exchange are estimated using various techniques. No hedge ratio technique examined consistently outperforms the unhedged portfolio in terms of variance reduction. Consequently, none of the hedge ratio methods in this study meet the general interpretation of FASB guidelines for a highly effective hedge. One of the major goals of deregulation is to bring about competition and increased efficiency in electricity markets. Previous research suggests that electricity exchanges may not be weak-form market efficient. A simple moving average trading rule is found to produce statistically and economically significant profits on the MISO exchange. This could call the long-term survivability of the MISO exchange into question.

  6. A real-world way to manage real options.

    PubMed

    Copeland, Tom; Tufano, Peter

    2004-03-01

    Each corporate growth project is an option, in the sense that managers face choices--push ahead or pull back--along the way. Yet many companies hesitate to apply options theory to initiatives such as R&D and geographic expansion, partly because these "real" options are highly complex. In this article, the authors make the case that the complexity of real options can be eased through the use of a binomial valuation model. Many of the problems with real-options analysis stem from the use of the Black-Scholes-Merton model, which isn't suited to real options. Binomial models, by contrast, are simpler mathematically, and you can tinker with a binomial model until it closely reflects the project you wish to value. Suppose your company is considering investing in a new plant. To use the binomial model, you must create an "event tree" to figure out the full range of possible values for the plant during the project's lifetime--next year, at the end of the design phase, upon completion. Then you work backward from the value at completion, factoring in the various investments, to determine the value of the project today. These calculations provide you with numbers for all the possible future values of the option at the various points where a decision needs to be made on whether to continue with the project. The authors also address another criticism of real options: that gaps often arise between theoretical and realized values of options of all types. Such gaps may be largely the result of managers exercising options at the wrong time. To improve the way it manages its real options, a company can look out for the decision trigger points that correspond to the nodes on a binomial decision tree. The trigger points should not only tell managers when they need to decide on exercise but also specify rules governing the exercise decisions.

  7. Reversible Control of Nanoparticle Functionalization and Physicochemical Properties by Dynamic Covalent Exchange.

    PubMed

    Della Sala, Flavio; Kay, Euan R

    2015-03-27

    Existing methods for the covalent functionalization of nanoparticles rely on kinetically controlled reactions, and largely lack the sophistication of the preeminent oligonucleotide-based noncovalent strategies. Here we report the application of dynamic covalent chemistry for the reversible modification of nanoparticle (NP) surface functionality, combining the benefits of non-biomolecular covalent chemistry with the favorable features of equilibrium processes. A homogeneous monolayer of nanoparticle-bound hydrazones can undergo quantitative dynamic covalent exchange. The pseudomolecular nature of the NP system allows for the in situ characterization of surface-bound species, and real-time tracking of the exchange reactions. Furthermore, dynamic covalent exchange offers a simple approach for reversibly switching-and subtly tuning-NP properties such as solvophilicity.

  8. On the security of a simple three-party key exchange protocol without server's public keys.

    PubMed

    Nam, Junghyun; Choo, Kim-Kwang Raymond; Park, Minkyu; Paik, Juryon; Won, Dongho

    2014-01-01

    Authenticated key exchange protocols are of fundamental importance in securing communications and are now extensively deployed for use in various real-world network applications. In this work, we reveal major previously unpublished security vulnerabilities in the password-based authenticated three-party key exchange protocol according to Lee and Hwang (2010): (1) the Lee-Hwang protocol is susceptible to a man-in-the-middle attack and thus fails to achieve implicit key authentication; (2) the protocol cannot protect clients' passwords against an offline dictionary attack; and (3) the indistinguishability-based security of the protocol can be easily broken even in the presence of a passive adversary. We also propose an improved password-based authenticated three-party key exchange protocol that addresses the security vulnerabilities identified in the Lee-Hwang protocol.

  9. Forecasting Stock Exchange Movements Using Artificial Neural Network Models and Hybrid Models

    NASA Astrophysics Data System (ADS)

    Güreşen, Erkam; Kayakutlu, Gülgün

    Forecasting stock exchange rates is an important financial problem that is receiving increasing attention. During the last few years, a number of neural network models and hybrid models have been proposed for obtaining accurate prediction results, in an attempt to outperform the traditional linear and nonlinear approaches. This paper evaluates the effectiveness of neural network models; recurrent neural network (RNN), dynamic artificial neural network (DAN2) and the hybrid neural networks which use generalized autoregressive conditional heteroscedasticity (GARCH) and exponential generalized autoregressive conditional heteroscedasticity (EGARCH) to extract new input variables. The comparison for each model is done in two view points: MSE and MAD using real exchange daily rate values of Istanbul Stock Exchange (ISE) index XU10).

  10. Australian Universities' Strategic Goals of Student Exchange and Participation Rates in Outbound Exchange Programmes

    ERIC Educational Resources Information Center

    Daly, Amanda; Barker, Michelle

    2010-01-01

    International student exchange programmes are acknowledged as one aspect of a broader suite of internationalisation strategies aimed at enhancing students' intercultural understanding and competence. The decision to participate in an exchange programme is dependent on both individual and contextual factors such as student exchange policies and…

  11. 78 FR 46622 - Application of Topaz Exchange, LLC for Registration as a National Securities Exchange; Findings...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-01

    ... type of Industry Director shall always be equal to one another.\\22\\ \\22\\ See Topaz Exchange.... Ownership Structure: Ownership and Voting Limitations As noted above in Section II.A, Topaz Exchange will be... with the governance structure of other exchanges, ISE Holdings' Board may waive the 40%...

  12. Exchange Studies as Actor-Networks: Following Korean Exchange Students in Swedish Higher Education

    ERIC Educational Resources Information Center

    Ahn, Song-ee

    2011-01-01

    This article explores how Korean exchange students organized their studies during exchange programs in Swedish higher education. For most students, the programs became a disordered period in relation to their education. The value of exchange studies seems mainly to be extra-curricular. Drawing upon actor network theory, the article argues that the…

  13. Single-spin asymmetries from two-photon exchange in elastic electron proton scattering

    SciTech Connect

    A.V. Afanasev; N.P. Merenkov

    2005-02-01

    The parity-conserving single-spin beam asymmetry of elastic electron-proton scattering is induced by an absorptive part of the two-photon exchange amplitude. We demonstrate that this asymmetry has logarithmic and double-logarithmic enhancement due to contributions of hard collinear quasi-real photons. An optical theorem is used to evaluate the asymmetry in terms of the total photoproduction cross section on the proton.

  14. Polychronicity and its Impact on Leader-Member Exchange and Outcome Behaviors

    DTIC Science & Technology

    2008-05-01

    role interpretation. Hillsdale, NJ: Erlbaum. Eagly, A. H., & Karau, S. J. (2002). Role congruity theory of prejudice toward female leaders...different perceptions that result 12 from these behaviors. This issue is directly tied to Eagly’s (1987) social role theory that states that people...Martin, R. (2005). From ideal to real: A longitudinal study of the role of implicit leadership theories on leader-member exchanges and employee

  15. Making real options really work.

    PubMed

    van Putten, Alexander B; MacMillan, Ian C

    2004-12-01

    As a way to value growth opportunities, real options have had a difficult time catching on with managers. Many CFOs believe the method ensures the overvaluation of risky projects. This concern is legitimate, but abandoning real options as a valuation model isn't the solution. Companies that rely solely on discounted cash flow (DCF) analysis underestimate the value of their projects and may fail to invest enough in uncertain but highly promising opportunities. CFOs need not--and should not--choose one approach over the other. Far from being a replacement for DCF analysis, real options are an essential complement, and a project's total value should encompass both. DCF captures a base estimate of value; real options take into account the potential for big gains. This is not to say that there aren't problems with real options. As currently applied, they focus almost exclusively on the risks associated with revenues, ignoring the risks associated with a project's costs. It's also true that option valuations almost always ignore assets that an initial investment in a subsequently abandoned project will often leave the company. In this article, the authors present a simple formula for combining DCF and option valuations that addresses these two problems. Using an integrated approach, managers will, in the long run, select better projects than their more timid competitors while keeping risk under control. Thus, they will outperform their rivals in both the product and the capital markets.

  16. Ion exchange in the nuclear industry

    SciTech Connect

    Bibler, J.P.

    1990-01-01

    Ion exchange is used in nearly every part of the nuclear fuel cycle -- from the purification of uranium from its ore to the final recovery of uranium and transmutation products. Ion exchange also plays a valuable role in the management of nuclear wastes generated in the fuel cycle.

  17. Ion exchange in the nuclear industry

    SciTech Connect

    Bibler, J.P.

    1990-12-31

    Ion exchange is used in nearly every part of the nuclear fuel cycle -- from the purification of uranium from its ore to the final recovery of uranium and transmutation products. Ion exchange also plays a valuable role in the management of nuclear wastes generated in the fuel cycle.

  18. 47 CFR 22.880 - Information exchange.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Information exchange. 22.880 Section 22.880...-Ground Radiotelephone Service Commercial Aviation Air-Ground Systems § 22.880 Information exchange. (a...-ground system licensee must provide the following information to the public safety/CII licensee at...

  19. Heat Exchanger Lab for Chemical Engineering Undergraduates

    ERIC Educational Resources Information Center

    Rajala, Jonathan W.; Evans, Edward A.; Chase, George G.

    2015-01-01

    Third year chemical engineering undergraduate students at The University of Akron designed and fabricated a heat exchanger for a stirred tank as part of a Chemical Engineering Laboratory course. The heat exchanger portion of this course was three weeks of the fifteen week long semester. Students applied concepts of scale-up and dimensional…

  20. 47 CFR 27.70 - Information exchange.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 2 2011-10-01 2011-10-01 false Information exchange. 27.70 Section 27.70 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.70 Information exchange. (a) Prior notification. Public...

  1. 47 CFR 27.70 - Information exchange.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 2 2012-10-01 2012-10-01 false Information exchange. 27.70 Section 27.70 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.70 Information exchange. (a) Prior notification. Public...

  2. 47 CFR 27.70 - Information exchange.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 2 2013-10-01 2013-10-01 false Information exchange. 27.70 Section 27.70 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.70 Information exchange. (a) Prior notification. Public...

  3. 47 CFR 27.70 - Information exchange.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 2 2014-10-01 2014-10-01 false Information exchange. 27.70 Section 27.70 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES MISCELLANEOUS WIRELESS COMMUNICATIONS SERVICES Technical Standards § 27.70 Information exchange. (a) Prior notification. Public...

  4. Titania bound sodium titanate ion exchanger

    DOEpatents

    DeFilippi, Irene C. G.; Yates, Stephen Frederic; Shen, Jian-Kun; Gaita, Romulus; Sedath, Robert Henry; Seminara, Gary Joseph; Straszewski, Michael Peter; Anderson, David Joseph

    1999-03-23

    This invention is method for preparing a titania bound ion exchange composition comprising admixing crystalline sodium titanate and a hydrolyzable titanium compound and, thereafter drying the titania bound crystalline sodium titanate and subjecting the dried titania bound ion exchange composition to optional compaction and calcination steps to improve the physical strength of the titania bound composition.

  5. 36 CFR 902.55 - Intragovernmental exchanges.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Intragovernmental exchanges. 902.55 Section 902.55 Parks, Forests, and Public Property PENNSYLVANIA AVENUE DEVELOPMENT CORPORATION... has two distinct purposes. One is to protect the full and frank exchange of ideas, views, and...

  6. Ion Exchange and Adsorption of Inorganic Contaminants

    EPA Science Inventory

    In the first part of the chapter, the fundamentals of ion exchange and adsorption processes are explained, with the goal of demonstrating how these principles influence process design for inorganic contaminant removal. In the second part, ion exchange and adsorption processes th...

  7. An approach for message exchange using archetypes.

    PubMed

    Moraes, João L C; Souza, Wanderley L; Cavalini, Luciana T; Pires, Luís F; Prado, Antonio F

    2013-01-01

    The application of ICT on the whole range of health sector activities, known as e-health, can simplify the access to health care services and will only be acceptable for realistic scenarios if it supports efficient information exchange amongst the caregivers and their patients. The aim of this paper is present an approach for message exchange to realistic scenarios.

  8. Pan-American Teletandem Language Exchange Project

    ERIC Educational Resources Information Center

    Castillo-Scott, Aurora

    2015-01-01

    This paper describes a TeleTandem language exchange project between English speaking Spanish students at Georgia College, USA, and Spanish speaking English students at Universidad de Concepción, Chile. The aim of the project was to promote linguistic skills and intercultural competence through a TeleTandem exchange. Students used Skype and Google…

  9. Timing matters in foreign exchange markets

    NASA Astrophysics Data System (ADS)

    Hirata, Yoshito; Aihara, Kazuyuki

    2012-02-01

    We show using nonlinear time series analysis that the timing of trades in foreign exchange markets has significant information. We apply a set of methods for analyzing point process data developed in neuroscience and nonlinear science. Our results imply that foreign exchange markets might be chaotic and have short-term predictability.

  10. Secondary School Student Exchanges. Discussion Paper

    ERIC Educational Resources Information Center

    US Department of State, 2007

    2007-01-01

    Educational and cultural exchanges are the cornerstone of U.S. public diplomacy and an integral component of foreign policy. To further this policy objective, the Department of State designates U.S. government, academic, and private sector entities to conduct educational and cultural exchange programs pursuant to a broad grant of authority from…

  11. Simulation of within-canopy radiation exchange

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Radiation exchange at the surface plays a critical role in the surface energy balance, plant microclimate, and plant growth. The ability to simulate the surface energy balance and the microclimate within the plant canopy is contingent upon simulation of the surface radiation exchange. A validation a...

  12. Educators Exchange Program, 1996. Evaluation Report.

    ERIC Educational Resources Information Center

    Armstrong, William B.; Turingan, Maria R.; Bersentes, Gina H.

    Following an initial effort in 1994, the Educators Exchange Program 1996 (EEP-96) was the second project completed under a training and educational exchange agreement reached between California's San Diego Community College District (SDCCD) and the republic of Mexico. In EEP-96, the district provided a five-week technological training program to…

  13. 77 FR 72813 - Information Collection; Land Exchanges

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-06

    ...; ] DEPARTMENT OF AGRICULTURE Forest Service Information Collection; Land Exchanges AGENCY: Forest Service, USDA... with no revision of a currently approved information collection, OMB 0596-0105, Land Exchanges. DATES... notice should be addressed to Vicky Wessling, National Land Adjustment Program Manager, Lands, 1601...

  14. The Story of Foreign Trade and Exchange.

    ERIC Educational Resources Information Center

    Fan, Cedric

    This comic-style booklet is one of a series of educational booklets published by the Federal Reserve Bank of New York. The booklet uses everyday language and lively illustrations to explain the benefits of international trade; the effects of tariffs and quotas; the significance of foreign exchange rates; how the foreign exchange market facilities…

  15. PROGRAMED EXCHANGES AND THE CONTROL OF AGGRESSION.

    ERIC Educational Resources Information Center

    ELLIS, DESMOND P.; HAMBLIN, ROBERT L.

    SYSTEMS OF EXCHANGE - USING THE EXTINCTION, DISTRACTION, AND SUBSTITUTION EFFECTS SYSTEMS - WERE IMPLEMENTED TO DECREASE AGGRESSION AND PROMOTE COOPERATION AND SCHOLARLY BEHAVIOR, THREE SYSTEMS WERE TESTED USING EXCHANGE THEORY AS A GUIDE. THE SUBJECTS WERE FIVE 4- AND 5-YEAR-OLD BOYS DIAGNOSED AS HYPERAGGRESSIVE. EXPERIMENTAL CONDITIONS INCLUDED…

  16. Labor Exchange Skills Project. Final Report.

    ERIC Educational Resources Information Center

    Dietrich, Eleanor; Hendrickson-Larson, Joanna; Hoppe, Ruth; Paige, Bruce; Rosenow, Steve

    The Labor Exchange Skills Project, which was conducted under the sponsorship and direction of the U.S. Department of Labor, Employment and Training Administration, was designed to develop a labor exchange skills database (ETA) that would improve the usability of many Department of Labor applications and products developed by other public and…

  17. Heat exchanger with a removable tube section

    DOEpatents

    Wolowodiuk, W.; Anelli, J.

    1975-07-29

    A heat exchanger is described in which the tube sheet is secured against primary liquid pressure, but which allows for easy removal of the tube section. The tube section is supported by a flange which is secured by a number of shear blocks, each of which extends into a slot which is immovable with respect to the outer shell of the heat exchanger. (auth)

  18. HEVC real-time decoding

    NASA Astrophysics Data System (ADS)

    Bross, Benjamin; Alvarez-Mesa, Mauricio; George, Valeri; Chi, Chi Ching; Mayer, Tobias; Juurlink, Ben; Schierl, Thomas

    2013-09-01

    The new High Efficiency Video Coding Standard (HEVC) was finalized in January 2013. Compared to its predecessor H.264 / MPEG4-AVC, this new international standard is able to reduce the bitrate by 50% for the same subjective video quality. This paper investigates decoder optimizations that are needed to achieve HEVC real-time software decoding on a mobile processor. It is shown that HEVC real-time decoding up to high definition video is feasible using instruction extensions of the processor while decoding 4K ultra high definition video in real-time requires additional parallel processing. For parallel processing, a picture-level parallel approach has been chosen because it is generic and does not require bitstreams with special indication.

  19. Giant exchange interaction in mixed lanthanides

    PubMed Central

    Vieru, Veacheslav; Iwahara, Naoya; Ungur, Liviu; Chibotaru, Liviu F.

    2016-01-01

    Combining strong magnetic anisotropy with strong exchange interaction is a long standing goal in the design of quantum magnets. The lanthanide complexes, while exhibiting a very strong ionic anisotropy, usually display a weak exchange coupling, amounting to only a few wavenumbers. Recently, an isostructural series of mixed (Ln = Gd, Tb, Dy, Ho, Er) have been reported, in which the exchange splitting is estimated to reach hundreds wavenumbers. The microscopic mechanism governing the unusual exchange interaction in these compounds is revealed here by combining detailed modeling with density-functional theory and ab initio calculations. We find it to be basically kinetic and highly complex, involving non-negligible contributions up to seventh power of total angular momentum of each lanthanide site. The performed analysis also elucidates the origin of magnetization blocking in these compounds. Contrary to general expectations the latter is not always favored by strong exchange interaction. PMID:27087470

  20. Nanoheterostructure cation exchange: anionic framework conservation.

    PubMed

    Jain, Prashant K; Amirav, Lilac; Aloni, Shaul; Alivisatos, A Paul

    2010-07-28

    In ionic nanocrystals the cationic sublattice can be replaced with a different metal ion via a fast, simple, and reversible place exchange, allowing postsynthetic modification of the composition of the nanocrystal, while preserving its size and shape. Here, we demonstrate that, during such an exchange, the anionic framework of the crystal is preserved. When applied to nanoheterostructures, this phenomenon ensures that compositional interfaces within the heterostructure are conserved throughout the transformation. For instance, a morphology composed of a CdSe nanocrystal embedded in a CdS rod (CdSe/CdS) was exchanged to a PbSe/PbS nanorod via a Cu(2)Se/Cu(2)S structure. During every exchange cycle, the seed size and position within the nanorod were preserved, as evident by excitonic features, Z-contrast imaging, and elemental line scans. Anionic framework conservation extends the domain of cation exchange to the design of more complex and unique nanostructures.

  1. Establishment Reality vs. Maintenance Reality: How Real Is Real Enough?

    ERIC Educational Resources Information Center

    Lindsay, E. D.; Murray, S.; Liu, D. K.; Lowe, D. B.; Bright, C. G.

    2009-01-01

    Remote and virtual laboratories are increasingly prevalent alternatives to the face-to-face laboratory experience; however, the question of their learning outcomes is yet to be fully investigated. There are many presumptions regarding the effectiveness of these approaches; foremost amongst these assumptions is that the experience must be "real" to…

  2. Dependable Real-Time Systems

    DTIC Science & Technology

    1991-09-30

    and F. Wang, "On thle Competitiveness of On-Line Real-Time Task Sc~eduling," to appear. Proc. Icai - Time Systemns Symposium, Dec 1991. 6. Biyabaiii, S...Stankovic, and K. Ramrnamritham, "System Support for lRal-’Vi111C Al: A Spring Project Perspective," Workshop on Real-Time .A1, ICAI ., August 198!). 29...Informatics, Computer S,,iety ,f India , t,, aptpear. 41 . Shilh, C. and J. A. Stankovic, "Distributed Deadlock Detection in Ada IRuntinv En vi- ronments," TRI

  3. The hydrogen exchange core and protein folding.

    PubMed Central

    Li, R.; Woodward, C.

    1999-01-01

    A database of hydrogen-deuterium exchange results has been compiled for proteins for which there are published rates of out-exchange in the native state, protection against exchange during folding, and out-exchange in partially folded forms. The question of whether the slow exchange core is the folding core (Woodward C, 1993, Trends Biochem Sci 18:359-360) is reexamined in a detailed comparison of the specific amide protons (NHs) and the elements of secondary structure on which they are located. For each pulsed exchange or competition experiment, probe NHs are shown explicitly; the large number and broad distribution of probe NHs support the validity of comparing out-exchange with pulsed-exchange/competition experiments. There is a strong tendency for the same elements of secondary structure to carry NHs most protected in the native state, NHs first protected during folding, and NHs most protected in partially folded species. There is not a one-to-one correspondence of individual NHs. Proteins for which there are published data for native state out-exchange and theta values are also reviewed. The elements of secondary structure containing the slowest exchanging NHs in native proteins tend to contain side chains with high theta values or be connected to a turn/loop with high theta values. A definition for a protein core is proposed, and the implications for protein folding are discussed. Apparently, during folding and in the native state, nonlocal interactions between core sequences are favored more than other possible nonlocal interactions. Other studies of partially folded bovine pancreatic trypsin inhibitor (Barbar E, Barany G, Woodward C, 1995, Biochemistry 34:11423-11434; Barber E, Hare M, Daragan V, Barany G, Woodward C, 1998, Biochemistry 37:7822-7833), suggest that developing cores have site-specific energy barriers between microstates, one disordered, and the other(s) more ordered. PMID:10452602

  4. [Regulation of the Na/Ca exchanger].

    PubMed

    DiPolo, R; Rojas, H; Beaugé, L

    1993-01-01

    The introduction of the squid giant axon preparation to studies on Ca homeostasis has proven very useful in laying the foundations in the study of Ca regulation. In particular the Na/Ca exchange mechanism has been characterized in terms of its regulatory processes using the well define technique of intracellular dialysis and membrane potential control. The Na/Ca exchange countertransport system plays a critical role in physiological processes including cardiac contractility and photoreception. It has also been implicate in the etiology of essential hypertension, cardiac arrhythmias and cell death. The ability of the Na/Ca exchanger to regulate the intracellular ionized Ca concentration ([Ca2+i]) under physiological conditions, is determined by the direction (net Ca efflux or Ca influx), and magnitude of transport. The direction of Ca transport is decided by the chemical gradient of sodium and calcium. The magnitude of the exchange is regulated by kinetic factors. This kinetic factors are critical since they decide whether the exchanger will mediate a net Ca movement under certain conditions. Recently, a large effort has been put together to characterize the secondary modulation of the Na/Ca exchanger. In particular modulation by MgATP and intracellular Ca2+. In nerve cells we have discover that MgATP regulates the exchanger through as phosphorylation-dephosphorylation processes most probably relate to the action of a kinase-phosphatase system. The other important ligand that regulates the exchange activity is the level of [Ca2+i]. We have found the presence of a regulatory site in the cytoplasmic face of the exchanger different from the transport site and probably responsible for turning the carrier "on" or "off". In this article we will depict some of the processes involved in the metabolic and ionic regulation of the Na/Ca exchanger.

  5. Exploring Alkaline Stable Organic Cations for Polymer Hydroxide Exchange Membranes

    DTIC Science & Technology

    2015-04-29

    Organic Cations for Polymer Hydroxide Exchange Membranes Hydroxide exchange membranes (HEMs) are important polymer electrolytes for electrochemical...Exploring Alkaline Stable Organic Cations for Polymer Hydroxide Exchange Membranes Report Title Hydroxide exchange membranes (HEMs) are important polymer ...constructing HEMs. EXPLORING ALKALINE STABLE ORGANIC CATIONS FOR POLYMER HYDROXIDE EXCHANGE MEMBRANES by Bingzi Zhang

  6. Comparison of chromatographic ion-exchange resins. III. Strong cation-exchange resins.

    PubMed

    Staby, Arne; Sand, Maj-Britt; Hansen, Ronni G; Jacobsen, Jan H; Andersen, Line A; Gerstenberg, Michael; Bruus, Ulla K; Jensen, Inge Holm

    2004-04-23

    A comparative study was performed on strong cation-exchangers to investigate the pH dependence, efficiency, binding strength, particle size distribution, static and dynamic capacity, and SEM pictures of chromatographic resins. The resins tested included: SP Sepharose XL, Poros 50 HS, Toyopearl SP 550c, SP Sepharose BB, Source 30S, TSKGel SP-5PW-HR20, and Toyopearl SP 650c. Testing was performed with four different proteins: anti-FVII Mab (IgG), aprotinin, lysozyme, and myoglobin. Dependence of pH on retention was generally very low for proteins with high pI. An unexpected binding at pH 7.5 of anti-FVII Mab with pI < 7.5 was observed on several resins. Efficiency results show the expected trend of higher dependence of the plate height with increasing flow rate of soft resins compared to resins for medium and high-pressure operation. Determination of particle size distribution by two independent methods, Coulter counting and SEM, was in very good agreement. The mono-dispersed nature of Source 30S was confirmed. Binding to cation-exchange resins as a function of ionic strength varies depending on the specific protein. Generally, binding and elution at high salt concentration may be performed with Toyopearl SP 550c and Poros 50 HS, while binding and elution at low salt concentration may be performed with Toyopearl SP 650c. A very high binding capacity was obtained with SP Sepharose XL. Comparison of static capacity and dynamic capacity at 10% break-through shows in general approximately 50-80% utilisation of the total available capacity during chromatographic operation. A general good agreement was obtained between this study and data obtained by others. The results of this study may be used for selection of resins for testing in process development. The validity of experiments and results with model proteins were tested using human insulin precursor in pure state and in real feed-stock on Toyopearl SP 550c, SP Sepharose BB, and Toyopearl SP 650c. Results showed good

  7. Time and foreign exchange markets

    NASA Astrophysics Data System (ADS)

    Berardi, Luca; Serva, Maurizio

    2005-08-01

    The definition of time is still an open question when one deals with high-frequency time series. If time is simply the calendar time, prices can be modeled as continuous random processes and values resulting from transactions or given quotes are discrete samples of this underlying dynamics. On the contrary, if one takes the business time point of view, price dynamics is a discrete random process, and time is simply the ordering according to which prices are quoted in the market. In this paper, we suggest that the business time approach is perhaps a better way of modeling price dynamics than calendar time. This conclusion comes from testing probability densities and conditional variances predicted by the two models against the experimental ones. The data set we use contains the DEM/USD exchange quotes provided to us by Olsen & Associates during a period of one year from January to December 1998. In this period, 1,620,843 quotes entries in the EFX system were recorded.

  8. Improved ceramic heat exchanger materials

    NASA Technical Reports Server (NTRS)

    Rauch, H. W.

    1980-01-01

    The development and evaluation of materials for potential application as heat exchanger structures in automotive gas turbine engines is discussed. Test specimens in the form of small monolithic bars were evaluated for thermal expansion and dimensional stability before and after exposure to sea salt and sulfuric acid, followed by short and long term cycling at temperatures up to 1200 C. The material finally selected, GE-7808, consists of the oxides, ZrO2-MgO-Al2O3-S1O2, and is described generically as ZrMAS. The original version was based on a commercially available cordierite (MAS) frit. However, a clay/talc mixture was demonstrated to be a satisfactory very low cost source of the cordierite (MAS) phase. Several full size honeycomb regenerator cores, about 10.2 cm thick and 55 cm diameter were fabricated from both the frit and mineral versions of GE-7808. The honeycomb cells in these cores had rectangular dimensions of about 0.5 mm x 2.5 mm and a wall thickness of approximately 0.2 mm. The test data show that GE-7808 is significantly more stable at 1100 C in the presence of sodium than the aluminosilicate reference materials. In addition, thermal exposure up to 1100 C, with and without sodium present, results in essentially no change in thermal expansion of GE-7808.

  9. Pulmonary gas exchange in diving.

    PubMed

    Moon, R E; Cherry, A D; Stolp, B W; Camporesi, E M

    2009-02-01

    Diving-related pulmonary effects are due mostly to increased gas density, immersion-related increase in pulmonary blood volume, and (usually) a higher inspired Po(2). Higher gas density produces an increase in airways resistance and work of breathing, and a reduced maximum breathing capacity. An additional mechanical load is due to immersion, which can impose a static transrespiratory pressure load as well as a decrease in pulmonary compliance. The combination of resistive and elastic loads is largely responsible for the reduction in ventilation during underwater exercise. Additionally, there is a density-related increase in dead space/tidal volume ratio (Vd/Vt), possibly due to impairment of intrapulmonary gas phase diffusion and distribution of ventilation. The net result of relative hypoventilation and increased Vd/Vt is hypercapnia. The effect of high inspired Po(2) and inert gas narcosis on respiratory drive appear to be minimal. Exchange of oxygen by the lung is not impaired, at least up to a gas density of 25 g/l. There are few effects of pressure per se, other than a reduction in the P50 of hemoglobin, probably due to either a conformational change or an effect of inert gas binding.

  10. The interplanetary exchange of photosynthesis.

    PubMed

    Cockell, Charles S

    2008-02-01

    Panspermia, the transfer of organisms from one planet to another, either through interplanetary or interstellar space, remains speculation. However, its potential can be experimentally tested. Conceptually, it is island biogeography on an interplanetary or interstellar scale. Of special interest is the possibility of the transfer of oxygenic photosynthesis between one planet and another, as it can initiate large scale biospheric productivity. Photosynthetic organisms, which must live near the surface of rocks, can be shown experimentally to be subject to destruction during atmospheric transit. Many of them grow as vegetative cells, which are shown experimentally to be susceptible to destruction by shock during impact ejection, although the effectiveness of this dispersal filter can be shown to be mitigated by the characteristics of the cells and their local environment. Collectively these, and other, experiments reveal the particular barriers to the cross-inoculation of photosynthesis. If oxygen biosignatures are eventually found in the atmospheres of extrasolar planets, understanding the potential for the interplanetary exchange of photosynthesis will aid in their interpretation.

  11. Modeling Inflation Using a Non-Equilibrium Equation of Exchange

    NASA Technical Reports Server (NTRS)

    Chamberlain, Robert G.

    2013-01-01

    Inflation is a change in the prices of goods that takes place without changes in the actual values of those goods. The Equation of Exchange, formulated clearly in a seminal paper by Irving Fisher in 1911, establishes an equilibrium relationship between the price index P (also known as "inflation"), the economy's aggregate output Q (also known as "the real gross domestic product"), the amount of money available for spending M (also known as "the money supply"), and the rate at which money is reused V (also known as "the velocity of circulation of money"). This paper offers first a qualitative discussion of what can cause these factors to change and how those causes might be controlled, then develops a quantitative model of inflation based on a non-equilibrium version of the Equation of Exchange. Causal relationships are different from equations in that the effects of changes in the causal variables take time to play out-often significant amounts of time. In the model described here, wages track prices, but only after a distributed lag. Prices change whenever the money supply, aggregate output, or the velocity of circulation of money change, but only after a distributed lag. Similarly, the money supply depends on the supplies of domestic and foreign money, which depend on the monetary base and a variety of foreign transactions, respectively. The spreading of delays mitigates the shocks of sudden changes to important inputs, but the most important aspect of this model is that delays, which often have dramatic consequences in dynamic systems, are explicitly incorporated.macroeconomics, inflation, equation of exchange, non-equilibrium, Athena Project

  12. Dynamical exchange-correlation potentials for the electron liquid

    NASA Astrophysics Data System (ADS)

    Qian, Zhixin; Vignale, Giovanni

    2002-03-01

    The imaginary parts of the exchange-correlation kernels f_xc^L,T(q=0, ω) in the linear density-density and transverse current-current response functions of a homogeneous electron liquid are calculated exactly at low frequency, to leading order in the Coulomb interaction. Combining these new results with the previously known high-frequency behaviors of Im f_xc^L,T(q=0, ω) and with the compressibility and the third frequency moment sum rules, we construct simple interpolation for Im f_xc^L,T(q=0, ω) in 3- and 2- dimensions. A novel feature of our interpolation formulas is that they explicitly take into account the two-plasmon component of the excitation spectrum: our longitudinal spectrum Im f_xc^L(q=0, ω) is thus intermediate between the Gross-Kohn interpolation, which ignores the two-plasmon contribution, and a recent approximate calculation by Nifosi, Conti, and Tosi, which probably overestimates it. Numerical results for both the real and imaginary parts of the exchange-correlation kernels at typical electron densities are presented, and compared with those obtained from previous approximations.

  13. Quantification of the heat exchange of chicken eggs.

    PubMed

    Van Brecht, A; Hens, H; Lemaire, J L; Aerts, J M; Degraeve, P; Berckmans, D

    2005-03-01

    In the incubation process of domestic avian eggs, the development of the embryo is mainly influenced by the physical microenvironment around the egg. Only small spatiotemporal deviations in the optimal incubator air temperature are allowed to optimize hatchability and hatchling quality. The temperature of the embryo depends on 3 factors: (1) the air temperature, (2) the exchange of heat between the egg and its microenvironment and (3) the time-variable heat production of the embryo. Theoretical estimates on the heat exchange between an egg and its physical microenvironment are approximated using equations that assume an approximate spherical shape for eggs. The objective of this research was to determine the heat transfer between the eggshell and its microenvironment and then compare this value to various theoretical estimates. By using experimental data, the overall and the convective heat transfer coefficients were determined as a function of heat production, air humidity, air speed, and air temperature. Heat transfer was not affected by air humidity but solely by air temperature, embryonic heat generation, and air speed and flow around eggs. Also, heat transfer in forced-air incubators occurs mainly by convective heat loss, which is dependent on the speed of airflow. A vertical airflow is more efficient than a horizontal airflow in transferring heat from the egg. We showed that describing an egg as a sphere underestimated convective heat transfer by 33% and was, therefore, too simplistic to accurately assess actual heat transfer from real eggs.

  14. Methods for Leveraging a Health Information Exchange for Public Health: Lessons Learned from the NW-PHIE Experience

    PubMed Central

    Trebatoski, M; Davies, J; Revere, D; Dobbs, D

    2010-01-01

    The intent of this article is to provide public health and health information exchanges (HIEs) insight into activities and processes for connecting public health with clinical care through HIEs. In 2007 the CDC issued a Request for Proposal (RFP) for the “Situational Awareness through Health Information Exchange” project. The project’s goals are to connect public health with health information exchanges (HIEs) to improve public health’s real-time understanding of communities’ population health and healthcare facility status. This article describes the approach and methodology used by the Northwest Public Health Information Exchange to achieve the project’s goals. The experience of the NWPHIE Collaboration provides an organizational and operational roadmap for implementing a successful regional HIE that ensures secure exchange and use of electronic health information between local and state public health and health care entities. PMID:23569587

  15. The National Water Data Exchange-capabilities and trends in the dissemination and exchange of water data

    USGS Publications Warehouse

    Burton, J.S.

    1998-01-01

    This paper discusses the programmes of the National Water Data Exchange (NAWDEX) in providing access to US Geological Survey (USGS) water data and water-related information. NAWDEX dissseminates water data and water-related information by working cooperatively through a network of 68 Assistance Centers to more than 430 member organizations. In addition, NAWDEX provides access to the USGS Water Data Storage System (WATSTORE) and the US Environmental Protection Agency's Storage and Retrieval System (STORET). Recently, the trend has been to make water resources data available over the World Wide Web on the Internet. The NAWDEX homepage, located at Uniform Resource Locator http://h2o.er.usgs.gov/public/nawdex/nawdex.html, provides links to (a) Selected Water Resources Abstracts; (b) National Water Conditions Report; (c) historical streamflow data: and (d) real-time streamflow conditions. NAWDEX also transfers data to users over the Internet through the file transfer protocol (FTP).

  16. Distribution Locational Real-Time Pricing Based Smart Building Control and Management

    SciTech Connect

    Hao, Jun; Dai, Xiaoxiao; Zhang, Yingchen; Zhang, Jun; Gao, Wenzhong

    2016-11-21

    This paper proposes an real-virtual parallel computing scheme for smart building operations aiming at augmenting overall social welfare. The University of Denver's campus power grid and Ritchie fitness center is used for demonstrating the proposed approach. An artificial virtual system is built in parallel to the real physical system to evaluate the overall social cost of the building operation based on the social science based working productivity model, numerical experiment based building energy consumption model and the power system based real-time pricing mechanism. Through interactive feedback exchanged between the real and virtual system, enlarged social welfare, including monetary cost reduction and energy saving, as well as working productivity improvements, can be achieved.

  17. Alice in the Real World

    ERIC Educational Resources Information Center

    Parker, Tom

    2012-01-01

    As a fifth-grade mathematics teacher, the author tries to create authentic problem-solving activities that connect to the world in which his students live. He discovered a natural connection to his students' real world at a computer camp. A friend introduced him to Alice, a computer application developed at Carnegie Mellon, under the leadership of…

  18. The Fantastic and the Real

    ERIC Educational Resources Information Center

    McLester, Susan

    2005-01-01

    The National Engineers Week Future City Competition provides compelling evidence of the power of pairing computer software and technology with traditional hands-on activities to teach challenging subject matter and also harder- to- measure "real" workplace skills. Now in its 13th year, the Competition asks middle school students to work in teams…

  19. Getting Real in the Academy

    ERIC Educational Resources Information Center

    Brown, Gary

    2004-01-01

    To say an issue is academic can mean it doesn't really matter, not in the real world, anyway. Gary Brown takes a critical look at how higher education has become unreal for many students and what we might do to help re-engage our institutions with the world. (Contains 17 notes.)

  20. Was Adam a Real Person?

    ERIC Educational Resources Information Center

    Lamoureux, Denis O.

    2011-01-01

    Belief in the historicity of Adam has been held firmly throughout the history of the church. In the light of modern biblical criticism and the evolutionary sciences, some conservative Christians are now questioning whether or not Adam was a real person. This paper argues that the existence of Adam in the opening chapters of scripture reflects an…