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Sample records for na area preoptica

  1. Caustic Recycle from Hanford Tank Waste Using Large Area NaSICON Structures (LANS)

    SciTech Connect

    Fountain, Matthew S.; Sevigny, Gary J.; Balagopal, S.; Bhavaraju, S.

    2009-03-31

    This report presents the results of a 5-day test of an electrochemical bench-scale apparatus using a proprietary (NAS-GY) material formulation of a (Na) Super Ion Conductor (NaSICON) membrane in a Large Area NaSICON Structures (LANS) configuration. The primary objectives of this work were to assess system performance, membrane seal integrity, and material degradation while removing Na from Group 5 and 6 tank waste from the Hanford Site.

  2. Mesopore control of high surface area NaOH-activated carbon.

    PubMed

    Tseng, Ru-Ling

    2006-11-15

    Activated carbon with BET surface areas in a narrow range from 2318 to 2474 m2/g was made by soaking the char made from corncob in a concentrated NaOH solution at NaOH/char ratios from 3 to 6; the mesopore volumes of the activated carbon were significantly changed from 21 to 58%. The relationships between pore properties (Sp, Vpore, Vmicro/Vpore, Dp) and NaOH dosage were investigated. Comparisons between the methods of NaOH and KOH activation revealed that NaOH activation can suitably control the mesopore specific volume of the activated carbon. Elemental analysis revealed that the H/C and O/C values of the activated carbons of NaOH/char ratios from 3 to 6 were significantly lower. SEM observation of surface hole variation of the activated carbon ascertained that the reaction process was inner pore etching. Based on the above three measurements and experimental investigations, the assumption made by previous researchers, namely that NaOH and KOH produce similar results, was challenged. Furthermore, the adsorption kinetics was used to investigate the adsorption rate of an Elovich equation to determine the relationships between the adsorption behavior on larger molecules (dyes) and smaller molecules (phenols) and the pore structure of the activated carbon.

  3. ProtNA-ASA: Protein-nucleic acid structural database with information on accessible surface area

    NASA Astrophysics Data System (ADS)

    Tkachenko, M. Y.; Boryskina, O. P.; Shestopalova, A. V.; Tolstorukov, M. Y.

    The article describes a new database (ProtNA-ASA), which combines the data on conformational parameters of nucleic acids and calculations of the accessible surface area (ASA) of nucleic acid atoms in protein-DNA/RNA complexes. As for October 2008, the database contains 214 DNA-protein and 28 RNA-protein non-homologous complexes. The database provides structural parameters that describe local geometry of base pairs and base-pair steps as well as backbone torsion angles. Additionally, total ASA of DNA/RNA atoms and the accessible area of atoms in the minor and major grooves are calculated. ProtNA-ASA database facilitates studying the relationship between the DNA/RNA conformation and availability of atoms for contact with proteins either in major or in minor groove for different nucleotides. Such an analysis is important for understanding the principles of molecular recognition including indirect sequence readout. The database is publicly available for use at http://www.protna.bio-page.org.

  4. Large-area multi-crystal NaI/Tl/ detectors for X-ray and gamma-ray astronomy

    NASA Technical Reports Server (NTRS)

    Fishman, G. J.; Austin, R. W.

    1976-01-01

    An array of large multicrystal NaI(Tl) detectors was constructed and used in a balloon-borne experiment to observe weak transient bursts of cosmic origin. The array had an active area of about 1 sq m and was sensitive to photons above 50 keV. Localized bursts which were observed are attributed to long-lived phosphorescence following large energy deposits by cosmic rays in the crystals.

  5. Dynamic features of animate motion activate septal and preoptic areas in visually naïve chicks (Gallus gallus).

    PubMed

    Lorenzi, Elena; Mayer, Uwe; Rosa-Salva, Orsola; Vallortigara, Giorgio

    2017-06-23

    The septum is an evolutionarily well-conserved part of the limbic system. It is known to be involved in many aspects of social behavior and is considered a key node of the social behavior network, together with the preoptic area. Involvement of these two brain regions has been recently observed in newly hatched chicks exposed to the natural motion of a living conspecific. However, it is unknown whether these areas respond also to simple motion cues that elicit animacy perception in humans and social predispositions in chicks. For example, naïve chicks are attracted by visual objects that appear to spontaneously change their speed (an index of self-propulsion, typical of animate creatures). Here we show that the right septum and the preoptic area of newly hatched visually naïve chicks exposed to speed changes have higher neuronal activity (revealed by c-Fos expression), compared with that of chicks exposed to constant motion. We thus found an involvement of these two areas in the perception of motion cues associated with animacy in newly hatched chicks without any previous visual experience. This demonstrates their early involvement in processing simple motion cues that allow the detection of animate creatures and elicit social predispositions in this animal model, as well as preferential attention in human infants and the perception of animacy in human adults. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

  6. Low-surface-area hard carbon anode for na-ion batteries via graphene oxide as a dehydration agent.

    PubMed

    Luo, Wei; Bommier, Clement; Jian, Zelang; Li, Xin; Carter, Rich; Vail, Sean; Lu, Yuhao; Lee, Jong-Jan; Ji, Xiulei

    2015-02-04

    Na-ion batteries are emerging as one of the most promising energy storage technologies, particularly for grid-level applications. Among anode candidate materials, hard carbon is very attractive due to its high capacity and low cost. However, hard carbon anodes often suffer a low first-cycle Coulombic efficiency and fast capacity fading. In this study, we discover that doping graphene oxide into sucrose, the precursor for hard carbon, can effectively reduce the specific surface area of hard carbon to as low as 5.4 m(2)/g. We further reveal that such doping can effectively prevent foaming during caramelization of sucrose and extend the pyrolysis burnoff of sucrose caramel over a wider temperature range. The obtained low-surface-area hard carbon greatly improves the first-cycle Coulombic efficiency from 74% to 83% and delivers a very stable cyclic life with 95% of capacity retention after 200 cycles.

  7. Low-surface-area hard carbon anode for Na-ion batteries via graphene oxide as a dehydration agent

    DOE PAGES

    Luo, Wei; Bommier, Clement; Jian, Zelang; ...

    2015-02-04

    Na-ion batteries are emerging as one of the most promising energy storage technologies, particularly for grid-level applications. Among anode candidate materials, hard carbon is very attractive due to its high capacity and low cost. However, hard carbon anodes often suffer a low first-cycle Coulombic efficiency and fast capacity fading. In this study, we discover that doping graphene oxide into sucrose, the precursor for hard carbon, can effectively reduce the specific surface area of hard carbon to as low as 5.4 m²/g. We further reveal that such doping can effectively prevent foaming during caramelization of sucrose and extend the pyrolysis burn-offmore » of sucrose caramel over a wider temperature range. Thus, the obtained low-surface-area hard carbon greatly improves the first-cycle Coulombic efficiency from 74% to 83% and delivers a very stable cyclic life with 95% of capacity retention after 200 cycles.« less

  8. Low-surface-area hard carbon anode for Na-ion batteries via graphene oxide as a dehydration agent

    SciTech Connect

    Luo, Wei; Bommier, Clement; Jian, Zelang; Li, Xin; Carter, Rich; Vail, Sean; Lu, Yuhao; Lee, Jong -Jan; Ji, Xiulei

    2015-02-04

    Na-ion batteries are emerging as one of the most promising energy storage technologies, particularly for grid-level applications. Among anode candidate materials, hard carbon is very attractive due to its high capacity and low cost. However, hard carbon anodes often suffer a low first-cycle Coulombic efficiency and fast capacity fading. In this study, we discover that doping graphene oxide into sucrose, the precursor for hard carbon, can effectively reduce the specific surface area of hard carbon to as low as 5.4 m²/g. We further reveal that such doping can effectively prevent foaming during caramelization of sucrose and extend the pyrolysis burn-off of sucrose caramel over a wider temperature range. Thus, the obtained low-surface-area hard carbon greatly improves the first-cycle Coulombic efficiency from 74% to 83% and delivers a very stable cyclic life with 95% of capacity retention after 200 cycles.

  9. Low-Surface-Area Hard Carbon Anode for Na-Ion Batteries via Graphene Oxide as a Dehydration Agent

    SciTech Connect

    Luo, W; Bommier, C; Jian, ZL; Li, X; Carter, R; Vail, S; Lu, YH; Lee, JJ; Ji, XL

    2015-02-04

    Na-ion batteries are emerging as one of the most promising energy storage technologies, particularly for grid-level applications. Among anode candidate materials, hard carbon is very attractive due to its high capacity and low cost. However, hard carbon anodes often suffer a low first-cycle Coulombic efficiency and fast capacity fading. In this study, we discover that doping graphene oxide into sucrose, the precursor for hard carbon, can effectively reduce the specific surface area of hard carbon to as low as 5.4 m(2)/g. We further reveal that such doping can effectively prevent foaming during caramelization of sucrose and extend the pyrolysis burnoff of sucrose caramel over a wider temperature range. The obtained low-surface-area hard carbon greatly improves the first-cycle Coulombic efficiency from 74% to 83% and delivers a very stable cyclic life with 95% of capacity retention after 200 cycles.

  10. Dengue and chikungunya: long-distance spread and outbreaks in naïve areas

    PubMed Central

    Rezza, Giovanni

    2014-01-01

    Mosquito-borne virus infections, such as dengue and chikungunya, are continuously expanding their geographical range. The dengue virus, which is known to be a common cause of febrile illness in tropical areas of the Old World, is now widespread in the Americas. In most affected areas, all the four dengue virus serotypes have circulated. Recently, small clusters of dengue have been identified also in Southern Europe during the hot season. The chikungunya virus, initially restricted to Central Africa, where is a common cause of sporadic cases or small outbreaks, and Asia, where it is used to cause large epidemics, has recently invaded new territories. After ravaging Indian Ocean Islands and the Indian subcontinent, CHIKV caused an outbreak in north-eastern Italy. Recently, chikungunya has reached the Caribbean, causing for the first time a large epidemic on the American continent. Although Aedes aegypti is the main vector of both viruses, Aedes albopictus, the Asian ‘Tiger’ mosquito, is now playing an increasingly important role, contributing to their spread in temperate climate areas. Hereby, we focus the attention on outbreaks of dengue and chikungunya occurring in previously disease-free areas and discuss factors associated with the long-distance spread of the vector-borne infections, such as mutations increasing viral fitness, climate change, urbanization, and globalization of humans and vectors. PMID:25491436

  11. "Routine" versus earthquake-related behavior in Na-K-Mg geothermometry records of Vrancea area (Romania)

    NASA Astrophysics Data System (ADS)

    Mitrofan, H.; Chitea, F.; Marin, C.; Zugravescu, D.; Besutiu, L.; Tudorache, A.

    2009-04-01

    A several-years long geochemical monitoring operation has been initiated in April 2003, addressing a deep-origin groundwater discharge at Slanic Moldova, close to Vrancea seismic area. In order to interpret the evolution of the major cations concentrations, the Na-K-Mg geothermometer diagnosis method has been used. Similarly to results previously obtained worldwide (California; southwest Egypt), an anomalous fluctuation of the so-called "Na-K temperature" (a parameter which is assumed to approximate temperatures existing in a deep origin groundwater reservoir) has been detected on occurrence of a major earthquake (27 October 2004, Mw=5.8-6.0). The earthquake epicenter was positioned at 50 km away from the geochemical sampling site, the focal depth being approximately 95 km. Generally, Na-K temperature fluctuations may also occur "routinely", as a result of the admixture of various amounts of shallow, meteorically-derived waters, or due to variable degrees of chemical re-equilibration at shallower depths / lower temperatures. It was therefore important to investigate if the variations observed in the data values could be plausibly related to a seismogeneis process. In this respect, an appropriate diagnosis should be provided by a so-called "maturity index": that parameter estimates - by additionally considering the fast-readjusting K/Mg solute ratio - the hydrothermal solution departure from the chemical equilibrium state mirrored by the "Na-K temperature". By plotting the maturity index versus the Na-K temperature values for the Slanic Moldova spring, two distinct regimes became noticeable: one consisting of highly correlated data-points, occurring as a dense "cluster", and the other one including a series of more poorly correlated data-points, which appeared to "drift away" from the main "cluster". The "cluster" regime persisted during the entire period (in excess of 3 years) that followed the strongest Vrancea earthquake (27 October 2004, Mw=5.8-6.0) recorded

  12. Experiences with area specific spectrum stripping of NaI(Tl) gamma spectra.

    PubMed

    Aage, H K; Korsbech, U; Bargholz, K; Bystöm, S; Wedmark, M; Thorshaug, S

    2006-01-01

    Processing of airborne and carborne gamma-ray spectra (AGS and CGS) often includes the stripping (elimination) of the signals from natural radioactivity. Hereby the net result becomes the signals from man-made radioactivity or other radiation anomalies. The parameters needed for spectrum stripping are dependent on detector size and quality as well as on the energy windows. In addition they depend on the environmental geometry including the vehicle carrying the detector. For AGS the altitude also influences the parameters. In general the stripping parameters are determined from tedious laboratory or field measurements with known sources of natural radioactivity. Stripping parameters may, however, often be calculated from the actual survey data or from data from a similar area. Both post-processing and real-time processing are possible. The technique is useful for gamma source search, for detection of radiation anomalies and for mapping of contamination levels. The use of the technique is illustrated with field exercise data.

  13. Whole cowpea meal fortified with NaFeEDTA reduces iron deficiency among Ghanaian school children in a malaria endemic area.

    PubMed

    Abizari, Abdul-Razak; Moretti, Diego; Zimmermann, Michael B; Armar-Klemesu, Margaret; Brouwer, Inge D

    2012-10-01

    Cowpeas, like other legumes, contain high amounts of native iron but are rich in phytic acid (PA) and polyphenols (PP) that inhibit iron absorption. NaFeEDTA may overcome the combined inhibitory effect of PA and PP. Our objective was to test the efficacy of NaFeEDTA-fortified cowpea meal in improving iron status of school children in a malaria endemic area. We conducted a double-blind, controlled trial with 5- to 12-y-old school children from 2 rural communities in northern Ghana (n = 241). Eligible children were randomly assigned to 2 treatment groups to receive either cowpea meal fortified with 10 mg Fe/meal as NaFeEDTA, or an identical but nonfortified cowpea meal. Meals were provided 3 d/wk for a period of ~7 mo under strict supervision. Mass deworming and malaria antigenemia screening and treatment were carried out at baseline and 3.5 mo into the trial. Consumption of cowpea flour fortified with NaFeEDTA resulted in improvement of hemoglobin (P < 0.05), serum ferritin (P < 0.001), and body iron stores (P < 0.001) and reduction of transferrin receptor (P < 0.001) compared with nonfortified flour. Fortification resulted in a 30 and 47% reduction in the prevalence of iron deficiency (ID) and iron deficiency anemia (IDA) (P < 0.05), respectively. The results indicate that fortification of cowpea flour with NaFeEDTA overcomes the combined inhibitory effect of PA and PP and, when used for targeted school-based fortification of cowpea flour, is effective in reducing the prevalence of ID and IDA among school children in malaria endemic rural northern Ghana.

  14. Polychlorinated dibenzo-p-dioxins and dibenzofurans in blood and breast milk samples from residents of a schistosomiasis area with Na-PCP application in China.

    PubMed

    Xiao, Ke; Zhao, Xingru; Liu, Zhengtao; Zhang, Bing; Fang, Liping; Liu, Wenbin; Zheng, Minghui

    2010-04-01

    Schistosomiasis has prevailed in some areas of China for a long time. Chinese technical sodium pentachlorophenate (Na-PCP) has been used to control the spread of snail-borne schistosomiasis since the 1960s. Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), impurities contained in the Na-PCP, enter the soil and may accumulate in the food chain. In order to evaluate their potentially harmful effects on local residents, 50 breast milk samples and 20 blood samples were collected in 2004 from residents in the Dongting Lake area, one of China's known schistosomiasis areas. Levels of 17 PCDD/F congeners were measured in all samples, and DNA damage was simultaneously assessed in blood samples. The PCDD/F congener distribution patterns in human tissue samples from the Dongting Lake area were similar to those in Na-PCP, and the octachlorodibenzodioxin (OCDD) congener was predominant in all samples. We also had a primary investigation that the breast milk WHO-TEQ associated with some factors such as: age, dietary habit, body mass index (BMI) and the total menses times. In blood samples, the samples with higher OCDD level had higher DDS (DNA damage score) values than those samples with low OCDD level, which indicated that the higher DNA damage value in general population might be caused directly or indirectly by PCDD/Fs. The results also indicated that the WHO-TEQ values in blood were associated with age (r=0.6, p=0.007). 2010 Elsevier Ltd. All rights reserved.

  15. FUNDAMENTAL AREAS OF PHENOMENOLOGY (INCLUDING APPLICATIONS): Acoustic Band Gaps in Three-Dimensional NaCl-Type Acoustic Crystals

    NASA Astrophysics Data System (ADS)

    Fang, Nong-Yu; Wu, Fu-Gen; Zhang, Xin

    2008-08-01

    We present the acoustic band gaps (ABGs) for a geometry of three-dimensional complex acoustic crystals: the NaCl-type structure. By using the super cell method based on the plane-wave expansion method (PWE), we study the three configurations formed by water objects (either a sphere of different sizes or a cube) located at the vertices of simple cubic (SC) lattice and surrounded by mercury background. The numerical results show that ABGs larger than the original SC structure for all the three configurations can be obtained by adjusting the length-diameter ratio of adjacent objects but keeping the filling fraction (f = 0.25) of the unit cell unchanged. We also compare our results with that of 3D solid composites and find that the ABGs in liquid composites are insensitive to the shapes as that in the solid composites. We further prove that the decrease of the translation group symmetry is more efficient in creating the ABGs in 3D water-mercury systems.

  16. Up-regulation of Na + expression in the area postrema of total sleep deprived rats by TOF-SIMS analysis

    NASA Astrophysics Data System (ADS)

    Mai, Fu-Der; Chen, Bo-Jung; Ling, Yong-Chien; Wu, Un-In; Huang, Yi-Lun; Chang, Hung-Ming

    2008-12-01

    Area postrema (AP) is a circumventricular organ plays an important role in sodium homeostasis and cardiovascular regulation. Since sleep deficiency will cause cardiovascular dysfunction, the present study aims to determine whether sodium level would significantly alter in AP following total sleep deprivation (TSD). Sodium level was investigated in vivo by time-of-flight secondary ion mass spectrometry (TOF-SIMS). Clinical manifestation of cardiovascular function was demonstrated by mean arterial pressure (MAP) values. Results indicated that in normal rats, TOF-SIMS spectrum revealed a major peak of sodium ion counting as 5.61 × 10 5 at m/ z 23. The sodium ions were homogeneous distributed in AP without specific localization. However, following TSD, the sodium intensity was relatively increased (6.73 × 10 5) and the signal for sodium image was strongly expressed throughout AP with definite spatial distribution. MAP of TSD rats is 138 ± 5 mmHg, which is significantly higher than that of normal ones (121 ± 3 mmHg). Regarding AP is an important area for sodium sensation and development of hypernatremic related sympatho-excitation; up-regulation of sodium expression following TSD suggests that high sodium level might over-activate AP, through complex neuronal networks involving in sympathetic regulation, which could lead to the formation of TSD relevant cardiovascular diseases.

  17. Highly efficient Yb-free Er-La-Al doped ultra-low NA large mode area single-trench fiber laser.

    PubMed

    Jain, D; Alam, S; Jung, Y; Barua, P; Velazquez, M N; Sahu, J K

    2015-11-02

    We demonstrate a 60µm core diameter Yb free Er-La-Al doped single-trench fiber having a 0.038 ultra-low-NA, fabricated using conventional MCVD process in conjunction with solution doping technique. Numerical simulations predict an effective single mode operation with effective area varying from 1,820µm(2) to 1,960µm(2) (taking bend-induced modal distortion into account) for different thicknesses of trenches and resonant rings at a constant bend radius of 25cm. Moreover, all solid structure favors easy cleaving and splicing. Experimental measurements demonstrate a robust effective single mode operation. Furthermore, with a 4%-4% laser cavity, this fiber shows a record efficiency of 46% with respect to the absorbed pump power.

  18. Frontal areas contribute to reduced global coordination of resting-state gamma activities in drug-naïve patients with schizophrenia.

    PubMed

    Kikuchi, Mitsuru; Hashimoto, Takanori; Nagasawa, Tatsuya; Hirosawa, Tetsu; Minabe, Yoshio; Yoshimura, Masafumi; Strik, Werner; Dierks, Thomas; Koenig, Thomas

    2011-08-01

    Schizophrenia has been postulated to involve impaired neuronal cooperation in large-scale neural networks, including cortico-cortical circuitry. Alterations in gamma band oscillations have attracted a great deal of interest as they appear to represent a pathophysiological process of cortical dysfunction in schizophrenia. Gamma band oscillations reflect local cortical activities, and the synchronization of these activities among spatially distributed cortical areas has been suggested to play a central role in the formation of networks. To assess global coordination across spatially distributed brain regions, Omega complexity (OC) in multichannel EEG was proposed. Using OC, we investigated global coordination of resting-state EEG activities in both gamma (30-50 Hz) and below-gamma (1.5-30 Hz) bands in drug-naïve patients with schizophrenia and investigated the effects of neuroleptic treatment. We found that gamma band OC was significantly higher in drug-naïve patients with schizophrenia compared to control subjects and that a right frontal electrode (F3) contributed significantly to the higher OC. After neuroleptic treatment, reductions in the contribution of frontal electrodes to global OC in both bands correlated with the improvement of schizophrenia symptomatology. The present study suggests that frontal brain processes in schizophrenia were less coordinated with activity in the remaining brain. In addition, beneficial effects of neuroleptic treatment were accompanied by improvement of brain coordination predominantly due to changes in frontal regions. Our study provides new evidence of improper intrinsic brain integration in schizophrenia by investigating the resting-state gamma band activity. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Persistent pre-seismic signature detected by means of Na-K-Mg geothermometry records in a saline spring of Vrancea area (Romania)

    NASA Astrophysics Data System (ADS)

    Mitrofan, H.; Marin, C.; Zugrǎvescu, D.; Chitea, F.; Anghelache, M.-A.; Beşuå£Iu, L.; Tudorache, A.

    2010-02-01

    A six year-long hydrochemical monitoring operation was conducted in Vrancea seismic zone (Romania), addressing a saline spring that proved to be suitable for Na-K-Mg geothermometry diagnosis. During the considered time-interval (2003-2009), only one important earthquake (mb=5.8) occurred in Vrancea region, this circumstance providing an unambiguous reference-moment between pre-seismic and post-seismic periods. On occurrence of that earthquake, an anomalous fluctuation of the Na-K temperature was detected - a result largely similar to previous ones recorded worldwide (California, southwest Egypt, northeast India). Yet such fluctuations may not necessarily be induced by earthquake-associated processes: they can occur also "routinely", possibly reflecting some environmental, meteorologically-induced "noise". It was therefore important to examine whether the variations observed in the data values could be plausibly related to a seismogenesis process. By additionally investigating (in a "scattterplot" diagram) the correlation between the Na-K temperatures and the values of a so-called "maturity index", a specific pattern emerged, with pre-seismic data-points plotting in a distinct domain of the diagram; moreover, those data-points appeared to describe a "drift away" pathway with respect to the remaining data-points "cluster", recorded during the subsequent 4 years of post-seismic monitoring. The "drift away" pattern persistently evolved for at least 18 months, ending just before the mb=5.8 earthquake and consequently suggesting the existence of some kind of long-term precursory phenomenon.

  20. Decision Trees in the Analysis of the Intensity of Damage to Portal Frame Buildings in Mining Areas / Drzewa Decyzyjne W Analizie Intensywności Uszkodzeń Budynków Halowych Na Terenach Górniczych

    NASA Astrophysics Data System (ADS)

    Firek, Karol; Rusek, Janusz; Wodyński, Aleksander

    2015-09-01

    The article presents a preliminary database analysis regarding the technical condition of 94 portal frame buildings located in the mining area of Legnica-Głogów Copper District (LGOM), using the methodology of decision trees. The scope of the analysis was divided into two stages. The first one included creating a decision tree by a standard CART method, and determining the importance of individual damage indices in the values of the technical wear of buildings. The second one was based on verification of the created decision tree and the importance of these indices in the technical wear of buildings by means of a simulation of individual dendritic models using the method of random forest. The obtained results confirmed the usefulness of decision trees in the early stage of data analysis. This methodology allows to build the initial model to describe the interaction between variables and to infer about the importance of individual input variables. Celem prezentowanych w artykule badań było sprawdzenie możliwości pozyskiwania informacji na temat udziału uszkodzeń w zużyciu technicznym zabudowy terenu górniczego z wykorzystaniem metody drzew decyzyjnych. Badania przeprowadzono na podstawie utworzonej przez autorów bazy danych o stanie technicznym i uszkodzeniach 94 budynków typu halowego, usytuowanych na terenie górniczym Legnicko-Głogowskiego Okręgu Miedziowego (LGOM). Do analiz przyjęto metodę drzew decyzyjnych CART - Classification & Regression Tree, na bazie której utworzono model aproksymujący wartość zużycia technicznego budynków. W efekcie ustalono wpływ poszczególnych zmiennych na przebieg modelowanego procesu (Rys. 3 i 4). W drugim etapie, stosując metodę losowych lasów przeprowadzono weryfikację wyników uzyskanych dla modelu utworzonego metodą CART (Tab. 2). Przeprowadzone badania pozwoliły na ustalenie udziałów wyspecyfikowanych kategorii uszkodzeń elementów badanych budynków w ich stopniu zużycia technicznego. Najwi

  1. Application of trenchless methods for pipelines renovation on mining areas / Zastosowanie metod bezwykopowych do renowacji rurociągów na terenach górniczych

    NASA Astrophysics Data System (ADS)

    Kalisz, Piotr; Pacześniowski, Krzysztof

    2012-10-01

    Several trenchless methods are currently applied to repair damaged pipelines of territorial development networks. There exist many technologies of pipelines renovation no always useful to repair pipelines on mining and post-mining areas. In the paper influence of mining exploitation onto pipelines was presented with special regard of pipelines after accomplished renovation with use of trenchless methods. An evaluation of these methods application possibilities to the renovation of pipelines on mining areas was also carried out.

  2. Empirical Evidence for Species-Specific Export of Fish Naïveté from a No-Take Marine Protected Area in a Coastal Recreational Hook and Line Fishery

    PubMed Central

    Alós, Josep; Puiggrós, Antoni; Díaz-Gil, Carlos; Palmer, Miquel; Rosselló, Rosario; Arlinghaus, Robert

    2015-01-01

    No-take marine protected areas (MPAs) are assumed to enhance fisheries catch via the “spillover” effect, where biomass is exported to adjacent exploited areas. Recent studies in spearfishing fisheries suggest that the spillover of gear-naïve individuals from protected to unprotected sites increases catch rates outside the boundaries of MPAs. Whether this is a widespread phenomenon that also holds for other gear types and species is unknown. In this study, we tested if the distance to a Mediterranean MPA predicted the degree of vulnerability to hook and line in four small-bodied coastal fish species. With the assistance of underwater video recording, we investigated the interaction effect of the distance to the boundary of an MPA and species type relative to the latency time to ingest a natural bait, which was considered as a surrogate of fish naïveté or vulnerability to fishing. Vulnerability to angling increased (i.e., latency time decreased) within and near the boundary of an MPA for an intrinsically highly catchable species (Serranus scriba), while it remained constant for an intrinsically uncatchable control species (Chromis chromis). While all of the individuals of S. scriba observed within the MPA and surrounding areas were in essence captured by angling gear, only one fifth of individuals in the far locations were captured. This supports the potential for the spillover of gear-naïve and consequently more vulnerable fish from no-take MPAs. Two other species initially characterized as intermediately catchable (Coris julis and Diplodus annularis) also had a shorter latency time in the vicinity of an MPA, but for these two cases the trend was not statistically significant. Overall, our results suggest that an MPA-induced naïveté effect may not be universal and may be confined to only intrinsically highly catchable fish species. This fact emphasizes the importance of considering the behavioural dimension when predicting the outcomes of MPAs, otherwise

  3. Use of the photogrammetric data for vegetation inventory on urban areas. (Polish Title: Wykorzystanie danych fotogrametrycznych do inwentaryzacji zieleni na terenach zurbanizowanych)

    NASA Astrophysics Data System (ADS)

    Kubalska, J. L.; Preuss, R.

    2014-12-01

    This paper discusses the methodology of the implementation of an inventory of vegetation in an urban area using photogrammetric data in the form of color NIR "true - orthophotomap" (true - ortho) and the digital surface model (DSM) created with data from airborne laser scanning, or alternatively, with an automatic correlation of images. The vegetation inventory was conducted by classification on the basis of the characteristics contained in pixels of georeferenced true - ortho while taking into account the elevation data in the form of gridded DSM. To carry out the classification Erdas Imagine software was used. The correct classification process was preceded by the creation of the input data for this task. This data was obtained from the processing of digital aerial photos taken by a Vexcel UltraCam camera with the ground resolution GSD = 10cm and point clouds acquired from ALS. This processing included the generation of digital terrain model in the SCOP++ environment and the digital surface model in an Opals and Inpho environment. The Comparison of DSM created from two different sources of data showed the overall consistency and uniformity and the ability to use both models to generate a true - ortho product from digital aerial photographs. The work was performed on an INPHO photogrammetric workstation. "True - ortho" was generated from both the black and white NIR images and colour images. The classification carried out with the Erdas Imagine software proved that this software is suitable for classification based on the features extracted from the pixels with the simultaneous analysis of elevation data. Simultaneous use of data both from airborne laser scanning and colour infrared images made it possible to make an exact classification of vegetation on very difficult terrain, like built up urban areas. The results of the classification accuracy were evaluated by the visual verification in Google Street View application. At a time when airborne platforms are

  4. High resolution studies of gully erosion, sedimentation processes, and land use changes since the late Pleistocene and future trajectories in the Kazimierz Dolny area (Nałęczów Plateau, SE-Poland)

    NASA Astrophysics Data System (ADS)

    Dotterweich, M.; Rodzik, J.; Zgłobicki, W.; Schmitt, A.; Schmidtchen, G.; Bork, H. R.

    2012-04-01

    This paper presents the results of 30 years of research on the Doły Podmularskie gully system (catchment 0.35 km2 in size), which is situated in the south-western part of the loess-covered Nałęczów Plateau in SE-Poland. Detailed topographic, stratigraphic and pedologic investigations, and monitoring of a tributary gully (gully area: 0.7 ha, catchment: 2.5 ha), combined with historical, archaeological and palaeoecological records reveal a long and complex history in terms of the temporal and spatial extent and the impact of land use on gully erosion, and the long-term feed-back mechanisms between land use changes and natural processes since the end of the Pleistocene are also expressed. Phases of gully erosion and subsequent filling occurred in the Bronze Age and around the 10th to 11th century. The most severe deepening and expansion of the gully took place in the 17th century. The results also show that field structures and land use intensity had a significant influence on the frequency and magnitude of run-off, soil erosion, piping, and landslide events. The last significant erosion phase started in the mid-19th century with renewed headward retreatment and down-cutting into older gully fills. Today, most of the catchment is either forested or the land is covered in berry shrubs. In the future, the area will continue to produce sediments, because of the steep slopes and because there are still areas of bare soil with a low resistance to erosion, a legacy from past land uses, which will remain a factor affecting soil erosion and sedimentation processes in the future. This study is an example of how important it is to observe and understand slow geomorphologic processes, changes and rare extreme events in the light of land use changes when investigating long-term human-environment interactions.

  5. Landslide susceptibility assesssment in the Uttarakhand area (India) using GIS: a comparison study of prediction capability of naïve bayes, multilayer perceptron neural networks, and functional trees methods

    NASA Astrophysics Data System (ADS)

    Pham, Binh Thai; Tien Bui, Dieu; Pourghasemi, Hamid Reza; Indra, Prakash; Dholakia, M. B.

    2017-04-01

    The objective of this study is to make a comparison of the prediction performance of three techniques, Functional Trees (FT), Multilayer Perceptron Neural Networks (MLP Neural Nets), and Naïve Bayes (NB) for landslide susceptibility assessment at the Uttarakhand Area (India). Firstly, a landslide inventory map with 430 landslide locations in the study area was constructed from various sources. Landslide locations were then randomly split into two parts (i) 70 % landslide locations being used for training models (ii) 30 % landslide locations being employed for validation process. Secondly, a total of eleven landslide conditioning factors including slope angle, slope aspect, elevation, curvature, lithology, soil, land cover, distance to roads, distance to lineaments, distance to rivers, and rainfall were used in the analysis to elucidate the spatial relationship between these factors and landslide occurrences. Feature selection of Linear Support Vector Machine (LSVM) algorithm was employed to assess the prediction capability of these conditioning factors on landslide models. Subsequently, the NB, MLP Neural Nets, and FT models were constructed using training dataset. Finally, success rate and predictive rate curves were employed to validate and compare the predictive capability of three used models. Overall, all the three models performed very well for landslide susceptibility assessment. Out of these models, the MLP Neural Nets and the FT models had almost the same predictive capability whereas the MLP Neural Nets (AUC = 0.850) was slightly better than the FT model (AUC = 0.849). The NB model (AUC = 0.838) had the lowest predictive capability compared to other models. Landslide susceptibility maps were final developed using these three models. These maps would be helpful to planners and engineers for the development activities and land-use planning.

  6. Landslide susceptibility assesssment in the Uttarakhand area (India) using GIS: a comparison study of prediction capability of naïve bayes, multilayer perceptron neural networks, and functional trees methods

    NASA Astrophysics Data System (ADS)

    Pham, Binh Thai; Tien Bui, Dieu; Pourghasemi, Hamid Reza; Indra, Prakash; Dholakia, M. B.

    2015-12-01

    The objective of this study is to make a comparison of the prediction performance of three techniques, Functional Trees (FT), Multilayer Perceptron Neural Networks (MLP Neural Nets), and Naïve Bayes (NB) for landslide susceptibility assessment at the Uttarakhand Area (India). Firstly, a landslide inventory map with 430 landslide locations in the study area was constructed from various sources. Landslide locations were then randomly split into two parts (i) 70 % landslide locations being used for training models (ii) 30 % landslide locations being employed for validation process. Secondly, a total of eleven landslide conditioning factors including slope angle, slope aspect, elevation, curvature, lithology, soil, land cover, distance to roads, distance to lineaments, distance to rivers, and rainfall were used in the analysis to elucidate the spatial relationship between these factors and landslide occurrences. Feature selection of Linear Support Vector Machine (LSVM) algorithm was employed to assess the prediction capability of these conditioning factors on landslide models. Subsequently, the NB, MLP Neural Nets, and FT models were constructed using training dataset. Finally, success rate and predictive rate curves were employed to validate and compare the predictive capability of three used models. Overall, all the three models performed very well for landslide susceptibility assessment. Out of these models, the MLP Neural Nets and the FT models had almost the same predictive capability whereas the MLP Neural Nets (AUC = 0.850) was slightly better than the FT model (AUC = 0.849). The NB model (AUC = 0.838) had the lowest predictive capability compared to other models. Landslide susceptibility maps were final developed using these three models. These maps would be helpful to planners and engineers for the development activities and land-use planning.

  7. The effect of Na vapor on the Na content of chondrules

    NASA Technical Reports Server (NTRS)

    Lewis, R. Dean; Lofgren, Gary E.; Franzen, Hugo F.; Windom, Kenneth E.

    1993-01-01

    Chondrules contain higher concentrations of volatiles (Na) than expected for melt droplets in the solar nebula. Recent studies have proposed that chondrules may have formed under non-canonical nebular conditions such as in particle/gas-rich clumps. Such chondrule formation areas may have contained significant Na vapor. To test the hypothesis of whether a Na-rich vapor would minimize Na volatilization reaction rates in a chondrule analog and maintain the Na value of the melt, experiments were designed where a Na-rich vapor could be maintained around the sample. A starting material with a melting point lower that typical chondrules was required to keep the logistics of working with Na volatilization from NaCl within the realm of feasibility. The Knippa basalt, a MgO-rich alkali olivine basalt with a melting temperature of 1325 +/- 5 C and a Na2O content of 3.05 wt%, was used as the chondrule analog. Experiments were conducted in a 1 atm, gas-mixing furnace with the fO2 controlled by a CO/CO2 gas mixture and fixed at the I-W buffer curve. To determine the extent of Na loss from the sample, initial experiments were conducted at high temperatures (1300 C - 1350 C) for duration of up to 72 h without a Na-rich vapor present. Almost all (up to 98%) Na was volatilized in runs of 72 h. Subsequent trials were conducted at 1330 C for 16 h in the presence of a Na-rich vapor, supplied by a NaCl-filled crucible placed in the bottom of the furnace. Succeeding Knudsen cell weight-loss mass-spectrometry analysis of NaCl determined the P(sub Na) for these experimental conditions to be in the 10(exp -6) atm range. This value is considered high for nebula conditions but is still plausible for non-canonical environments. In these trials the Na2O content of the glass was maintained or in some cases increased; Na2O values ranged from 2.62% wt to 4.37% wt. The Na content of chondrules may be controlled by the Na vapor pressure in the chondrule formation region. Most heating events capable

  8. Synthesis of Na-A and/or Na-X zeolite/porous carbon composites from carbonized rice husk

    NASA Astrophysics Data System (ADS)

    Katsuki, Hiroaki; Komarneni, Sridhar

    2009-07-01

    Na-A and/or Na-X zeolite/porous carbon composites were prepared under hydrothermal conditions by NaOH dissolution of silica first from carbonized rice husk followed by addition of NaAlO 2 and in situ crystallization of zeolites i.e., using a two-step process. When a one-step process was used, both Na-A and Na-X zeolites crystallized on the surface of carbon. Na-A or Na-X zeolite crystals were prepared on the porous carbonized rice husk at 90 °C for 2-6 h by changing the SiO 2/Al 2O 3, H 2O/Na 2O and Na 2O/SiO 2 molar ratios of precursors in the two-step process. The surface area and NH 4+-cation exchange capacity (CEC) of Na-A zeolite/porous carbon were found to be 171 m 2/g and 506 meq/100 g, respectively, while those of Na-X zeolite/porous carbon composites were 676 m 2/g and 317 meq/100 g, respectively. Na-A and Na-X zeolites are well-known microporous and hydrophilic materials while carbonized rice husk was found to be mesoporous (pores of ˜3.9 nm) and hydrophobic. These hybrid microporous-mesoporous and hydrophilic-hydrophobic composites are expected to be useful for decontamination of metal cations as well as organic contaminants simultaneously.

  9. Effect of Na+ on surface fractal dimension of compacted bentonite

    NASA Astrophysics Data System (ADS)

    Xiang, G. S.; Xu, Y. F.; Jiang, H.

    2015-05-01

    Compacted Tsukinuno bentonite was immersed into NaCl solutions of different concentrations in oedometers, and the surface fractal dimension of bentonite-saline association was measured by nitrogen adsorption isotherms. The application of the Frenkel-Halsey-Hill equation and the Neimark thermodynamic method to nitrogen adsorption isotherms indicated that the surface roughness was greater for the bentonite-saline association. The surface fractal dimension of bentonite increased in the NaCl solution with low Na+ concentration, but decreased at high Na+ concentration. This process was accompanied by the same tendency in specific surface area and microporosity with the presence of Na+ coating in the clay particles.

  10. FT-IR and XRD analysis of natural Na-bentonite and Cu(II)-loaded Na-bentonite

    NASA Astrophysics Data System (ADS)

    Zhirong, Liu; Azhar Uddin, Md.; Zhanxue, Sun

    2011-09-01

    Na-bentonite has been studied extensively because of its strong adsorption capacity and complexation ability. In this work, surface area, total pore volume, mean pore diameter, TG, DTA, FT-IR and XRD were carried out in order to reveal the characteristics of natural Na-bentonite. XRD and FT-IR of natural Na-bentonite (China) and Cu-loaded Na-bentonite as a function of Na-bentonite dosage and temperature using batch technique were characterized in detail, respectively.

  11. FT-IR and XRD analysis of natural Na-bentonite and Cu(II)-loaded Na-bentonite.

    PubMed

    Zhirong, Liu; Azhar Uddin, Md; Zhanxue, Sun

    2011-09-01

    Na-bentonite has been studied extensively because of its strong adsorption capacity and complexation ability. In this work, surface area, total pore volume, mean pore diameter, TG, DTA, FT-IR and XRD were carried out in order to reveal the characteristics of natural Na-bentonite. XRD and FT-IR of natural Na-bentonite (China) and Cu-loaded Na-bentonite as a function of Na-bentonite dosage and temperature using batch technique were characterized in detail, respectively.

  12. Testing Na+ in blood

    PubMed Central

    Lava, Sebastiano A.G.; Bianchetti, Mario G.; Milani, Gregorio P.

    2017-01-01

    Abstract Both direct potentiometry and indirect potentiometry are currently used for Na+ testing in blood. These measurement techniques show good agreement as long as protein and lipid concentrations in blood remain normal. In severely ill patients, indirect potentiometry commonly leads to relevant errors in Na+ estimation: 25% of specimens show a disagreement between direct and indirect potentiometry, which is ≥4 mmol/L (mostly spuriously elevated Na+ level due to low circulating albumin concentration). There is a need for increased awareness of the poor performance of indirect potentiometry in some clinical settings.

  13. Shoot Na+ exclusion and increased salinity tolerance engineered by cell type-specific alteration of Na+ transport in Arabidopsis.

    PubMed

    Møller, Inge S; Gilliham, Matthew; Jha, Deepa; Mayo, Gwenda M; Roy, Stuart J; Coates, Juliet C; Haseloff, Jim; Tester, Mark

    2009-07-01

    Soil salinity affects large areas of cultivated land, causing significant reductions in crop yield globally. The Na+ toxicity of many crop plants is correlated with overaccumulation of Na+ in the shoot. We have previously suggested that the engineering of Na+ exclusion from the shoot could be achieved through an alteration of plasma membrane Na+ transport processes in the root, if these alterations were cell type specific. Here, it is shown that expression of the Na+ transporter HKT1;1 in the mature root stele of Arabidopsis thaliana decreases Na+ accumulation in the shoot by 37 to 64%. The expression of HKT1;1 specifically in the mature root stele is achieved using an enhancer trap expression system for specific and strong overexpression. The effect in the shoot is caused by the increased influx, mediated by HKT1;1, of Na+ into stelar root cells, which is demonstrated in planta and leads to a reduction of root-to-shoot transfer of Na+. Plants with reduced shoot Na+ also have increased salinity tolerance. By contrast, plants constitutively expressing HKT1;1 driven by the cauliflower mosaic virus 35S promoter accumulated high shoot Na+ and grew poorly. Our results demonstrate that the modification of a specific Na+ transport process in specific cell types can reduce shoot Na+ accumulation, an important component of salinity tolerance of many higher plants.

  14. Geotechnical Aspects of Revitalisation of Post-Mining Areas - An Example of the Adaptation of Katowice Hard Coal Mine for the New Silesian Museum / Geotechniczne aspekty rewitalizacji terenów pogórniczych - przykład adaptacji KWK "KATOWICE" na nowe muzeum śląskie

    NASA Astrophysics Data System (ADS)

    Cała, Marek; Ostręga, Anna

    2013-06-01

    The article presents the history of the Katowice Hard Coal Mine and the concept of revitalisation taking into consideration the historical development of the mine which today is closed. The concept accepted for realisation assumes adaptation of the post-mining area with its historical infrastructure for cultural functions, and namely for the construction of the New Silesian Museum. Basing the concept on the idea of minimum interference into the existing spatial layout of the former mine has had the result that the museum areas and garages have been designed under the surface of the area adjacent to the historic facilities of the mine. In relation therewith, it was necessary to carry out the works aimed at reinforcing foundations of the historic buildings and protecting the geotechnical pit slopes. The article presents the technological solutions applied to protect the historic buildings, the lift tower, and the excavations for new facilities of the Silesian Museum. Attention was drawn to the instability of the subsoil and of the rock mass due to previous mining operations conducted in the area, the need to adapt the protection technology to the existing conditions as well as the need of constant monitoring of geotechnical works underway.> It is emphasised that the presented investment is part of an ongoing process aimed at preserving the industrial part of the material cultural heritage of Upper Silesia, for centuries connected with hard coal mining and as such it stands a chance to become a showcase not only for Katowice but for the entire region of Silesia. W artykule przedstawiono historię Kopalni Węgla Kamiennego "Katowice" oraz koncepcję rewitalizacji uwzględniającą historyczną zabudowę nieczynnej już dziś kopalni. Przyjęta do realizacji koncepcja zakłada przystosowanie pogórniczego terenu wraz z zabytkową infrastrukturą dla funkcji kulturowych, a mianowicie budowy Nowego Muzeum Śląskiego. Siedziba Nowego Muzeum Śląskiego lokalizowana jest w

  15. Synthesis of Na-A and/or Na-X zeolite/porous carbon composites from carbonized rice husk

    SciTech Connect

    Katsuki, Hiroaki; Komarneni, Sridhar

    2009-07-15

    Na-A and/or Na-X zeolite/porous carbon composites were prepared under hydrothermal conditions by NaOH dissolution of silica first from carbonized rice husk followed by addition of NaAlO{sub 2} and in situ crystallization of zeolites i.e., using a two-step process. When a one-step process was used, both Na-A and Na-X zeolites crystallized on the surface of carbon. Na-A or Na-X zeolite crystals were prepared on the porous carbonized rice husk at 90 deg. C for 2-6 h by changing the SiO{sub 2}/Al{sub 2}O{sub 3}, H{sub 2}O/Na{sub 2}O and Na{sub 2}O/SiO{sub 2} molar ratios of precursors in the two-step process. The surface area and NH{sub 4}{sup +}-cation exchange capacity (CEC) of Na-A zeolite/porous carbon were found to be 171 m{sup 2}/g and 506 meq/100 g, respectively, while those of Na-X zeolite/porous carbon composites were 676 m{sup 2}/g and 317 meq/100 g, respectively. Na-A and Na-X zeolites are well-known microporous and hydrophilic materials while carbonized rice husk was found to be mesoporous (pores of {approx}3.9 nm) and hydrophobic. These hybrid microporous-mesoporous and hydrophilic-hydrophobic composites are expected to be useful for decontamination of metal cations as well as organic contaminants simultaneously. - Graphical Abstract: Novel Na-X zeolite/porous carbon composite.

  16. Compact clinical high-NA multiphoton endoscopy

    NASA Astrophysics Data System (ADS)

    Weinigel, Martin; Breunig, Hans Georg; Fischer, Peter; Kellner-Höfer, Marcel; Bückle, Rainer; König, Karsten

    2012-02-01

    Multiphoton imaging methods are excellent for non-invasive imaging of living tissue without any need of additional contrast agents. The increasing demand for endoscopic techniques has forced the development of multiphoton endoscopes for imaging of areas with reduced accessibility like chronic wounds. Gradient index (GRIN) lenses can miniaturize the bulky distal focusing optics of conventional tomographs to a diameter of less than 1.4 mm and a numerical aperture (NA) of 0.8. We combined a high NA clinical multiphoton endoscope with existing multiphoton tomographs like the DermaInspect® and the MPTflex® to enable the examination of wound healing processes.

  17. NATURAL AREA ROADLESS AREA, FLORIDA.

    USGS Publications Warehouse

    Patterson, Sam H.; Crandall, Thomas M.

    1984-01-01

    Mineral surveys of the Natural Area Roadless Area, Florida, identified a substantiated resource potential for scattered low-grade phosphate deposits. The area has little promise for the occurrence of other mineral resources or oil and gas, although the possibilities for the occurrence of these two hydrocarbons cannot be ruled out. The only mineral material that has been produced in the area is clayey sand used in stabilizing roads. Peaty material is present in swamps in the roadless area, but none of it is thick or pure and no resource potential was identified. Limestone underlies all of the Natural Area Roadless Area but is under too much overburden for quarrying. Heavy minerals are present in the area but are not sufficiently concentrated to consider the area as having resource potential.

  18. Friedrichbeckeite, K (□0.5Na0.5)2 (Mg0.8Mn0.1Fe0.1)2 (Be0.6 Mg0.4)3 [Si12O30], a new milarite-type mineral from the Bellerberg volcano, Eifel area, Germany

    NASA Astrophysics Data System (ADS)

    Lengauer, C. L.; Hrauda, N.; Kolitsch, U.; Krickl, R.; Tillmanns, E.

    2009-07-01

    Friedrichbeckeite is a new milarite-type mineral. It was found in a single silicate-rich xenolith from a quarry at the Bellerberg volcano near Ettringen, eastern Eifel volcanic area, Germany. It forms thin tabular crystals flattened on {0001}, with a maximum diameter of 0.6 mm and a maximum thickness of 0.1 mm. It is associated with quartz, tridymite, augite, sanidine, magnesiohornblende, enstatite, pyrope, fluorapatite, hematite, braunite and roedderite. Friedrichbeckeite is light yellow, with white to light cream streak and vitreous lustre. It is brittle with irregular fracture and no cleavage, Mohs hardness of 6, calculated density is 2.686 gcm-3. Optically, it is uniaxial positive with nω = 1.552(2) and nɛ = 1.561(2) at 589.3 nm and a distinct pleochroism from yellow (//ω) to light blue (//ɛ). Electron microprobe analyses yielded (wt.%): Na2O 2.73, K2O 4.16, BeO 4.67, MgO 11.24, MnO 2.05, FeO 1.76, Al2O3 0.15, SiO2 73.51, (Σ CaO, TiO2 = 0.06) sum 100.33 (BeO determined by LA-ICP-MS). The empirical formula based on Si = 12 is K0.87 Na0.86 (Mg1.57Mn0.28Fe0.24)Σ2.09 (Be1.83 Mg1.17)Σ3.00 [Si12O30], and the simplified formula can be given as K (□0.5Na0.5)2 (Mg0.8Mn0.1Fe0.1)2 (Be0.6 Mg0.4)3 [Si12O30]. Friedrichbeckeite is hexagonal, space-group P6/ mcc, with a = 9.970(1), c = 14.130(3) Å, V = 1216.4(3) Å3, and Z = 2. The strongest lines in the X-ray powder diffraction pattern are ( d in Å / I obs / hkl): 3.180 / 100 / 121, 2.885 / 70 / 114, 4.993 / 30 / 110, 4.081 / 30 / 112, 3.690 / 30 / 022. A single-crystal structure refinement ( R1 = 3.62 %) confirmed that the structure is isotypic with milarite and related [12] C [9] B 2 [6] A 2 [4] T23 [[4] T112O30] compounds. The C-site is dominated by potassium, the B-site is almost half occupied by sodium, and the A-site is dominated by Mg. The site-scattering at the T2-site can be refined to a Be/(Be + Mg) value close to 0.61; the T1-site is occupied by Si. Micro-Raman spectroscopy reveals an increasing

  19. Characterization of ZnAl cast alloys with Na addition

    SciTech Connect

    Gancarz, Tomasz; Cempura, Grzegorz; Skuza, Wojciech

    2016-01-15

    This study was aimed at evaluating the microstructural change and thermal, electrical and mechanical properties with the addition of Na to eutectic ZnAl alloys. Solders based on eutectic ZnAl containing 0.2 to 3.0 (wt.%) of Na were developed for high temperature solder. Differential scanning calorimetry (DSC) measurements were performed to determine the melting temperatures of the alloys. Thermal linear expansion and electrical resistivity measurements were performed over − 50 °C to 300 °C and 30 °C to 300 °C temperature ranges, respectively. The microstructure of the specimens was analyzed using scanning (SEM) and transmission electron microscopy (TEM) techniques. Chemical microanalysis was performed by energy-dispersive X-ray spectroscopy (EDS) on SEM and TEM. The precipitates of NaZn{sub 13} were confirmed by X-ray diffraction (XRD) measurements and selected area electron diffraction (SAED) techniques. The addition of Na to eutectic ZnAl alloy increased the electrical resistivity and reduced the coefficient of thermal expansion; however, the melting point did not change. The mechanical properties, strain and microhardness increased with Na content in alloys. - Highlights: • High temperature soldering materials of ZnAl with Na were designed and characterized. • Precipitates of NaZn{sub 13}were observed and confirmed using TEM and XRD. • Addition of Na to eutectic ZnAl cussed increased mechanical properties. • NaZn{sub 13} caused increased electrical resistivity and microhardness, and reduced the CTE.

  20. Regulation of cardiac myocyte contractility by phospholemman: Na+/Ca2+ exchange versus Na+ -K+ -ATPase.

    PubMed

    Song, Jianliang; Zhang, Xue-Qian; Wang, JuFang; Cheskis, Ellina; Chan, Tung O; Feldman, Arthur M; Tucker, Amy L; Cheung, Joseph Y

    2008-10-01

    Phospholemman (PLM) regulates cardiac Na(+)/Ca(2+) exchanger (NCX1) and Na(+)-K(+)-ATPase in cardiac myocytes. PLM, when phosphorylated at Ser(68), disinhibits Na(+)-K(+)-ATPase but inhibits NCX1. PLM regulates cardiac contractility by modulating Na(+)-K(+)-ATPase and/or NCX1. In this study, we first demonstrated that adult mouse cardiac myocytes cultured for 48 h had normal surface membrane areas, t-tubules, and NCX1 and sarco(endo)plasmic reticulum Ca(2+)-ATPase levels, and retained near normal contractility, but alpha(1)-subunit of Na(+)-K(+)-ATPase was slightly decreased. Differences in contractility between myocytes isolated from wild-type (WT) and PLM knockout (KO) hearts were preserved after 48 h of culture. Infection with adenovirus expressing green fluorescent protein (GFP) did not affect contractility at 48 h. When WT PLM was overexpressed in PLM KO myocytes, contractility and cytosolic Ca(2+) concentration ([Ca(2+)](i)) transients reverted back to those observed in cultured WT myocytes. Both Na(+)-K(+)-ATPase current (I(pump)) and Na(+)/Ca(2+) exchange current (I(NaCa)) in PLM KO myocytes rescued with WT PLM were depressed compared with PLM KO myocytes. Overexpressing the PLMS68E mutant (phosphomimetic) in PLM KO myocytes resulted in the suppression of I(NaCa) but had no effect on I(pump). Contractility, [Ca(2+)](i) transient amplitudes, and sarcoplasmic reticulum Ca(2+) contents in PLM KO myocytes overexpressing the PLMS68E mutant were depressed compared with PLM KO myocytes overexpressing GFP. Overexpressing the PLMS68A mutant (mimicking unphosphorylated PLM) in PLM KO myocytes had no effect on I(NaCa) but decreased I(pump). Contractility, [Ca(2+)](i) transient amplitudes, and sarcoplasmic reticulum Ca(2+) contents in PLM KO myocytes overexpressing the S68A mutant were similar to PLM KO myocytes overexpressing GFP. We conclude that at the single-myocyte level, PLM affects cardiac contractility and [Ca(2+)](i) homeostasis primarily by its direct

  1. Na+ coordination at the Na2 site of the Na+/I- symporter.

    PubMed

    Ferrandino, Giuseppe; Nicola, Juan Pablo; Sánchez, Yuly E; Echeverria, Ignacia; Liu, Yunlong; Amzel, L Mario; Carrasco, Nancy

    2016-09-13

    The sodium/iodide symporter (NIS) mediates active I(-) transport in the thyroid-the first step in thyroid hormone biosynthesis-with a 2 Na(+): 1 I(-) stoichiometry. The two Na(+) binding sites (Na1 and Na2) and the I(-) binding site interact allosterically: when Na(+) binds to a Na(+) site, the affinity of NIS for the other Na(+) and for I(-) increases significantly. In all Na(+)-dependent transporters with the same fold as NIS, the side chains of two residues, S353 and T354 (NIS numbering), were identified as the Na(+) ligands at Na2. To understand the cooperativity between the substrates, we investigated the coordination at the Na2 site. We determined that four other residues-S66, D191, Q194, and Q263-are also involved in Na(+) coordination at this site. Experiments in whole cells demonstrated that these four residues participate in transport by NIS: mutations at these positions result in proteins that, although expressed at the plasma membrane, transport little or no I(-) These residues are conserved throughout the entire SLC5 family, to which NIS belongs, suggesting that they serve a similar function in the other transporters. Our findings also suggest that the increase in affinity that each site displays when an ion binds to another site may result from changes in the dynamics of the transporter. These mechanistic insights deepen our understanding not only of NIS but also of other transporters, including many that, like NIS, are of great medical relevance.

  2. Shoot Na+ Exclusion and Increased Salinity Tolerance Engineered by Cell Type–Specific Alteration of Na+ Transport in Arabidopsis[W][OA

    PubMed Central

    Møller, Inge S.; Gilliham, Matthew; Jha, Deepa; Mayo, Gwenda M.; Roy, Stuart J.; Coates, Juliet C.; Haseloff, Jim; Tester, Mark

    2009-01-01

    Soil salinity affects large areas of cultivated land, causing significant reductions in crop yield globally. The Na+ toxicity of many crop plants is correlated with overaccumulation of Na+ in the shoot. We have previously suggested that the engineering of Na+ exclusion from the shoot could be achieved through an alteration of plasma membrane Na+ transport processes in the root, if these alterations were cell type specific. Here, it is shown that expression of the Na+ transporter HKT1;1 in the mature root stele of Arabidopsis thaliana decreases Na+ accumulation in the shoot by 37 to 64%. The expression of HKT1;1 specifically in the mature root stele is achieved using an enhancer trap expression system for specific and strong overexpression. The effect in the shoot is caused by the increased influx, mediated by HKT1;1, of Na+ into stelar root cells, which is demonstrated in planta and leads to a reduction of root-to-shoot transfer of Na+. Plants with reduced shoot Na+ also have increased salinity tolerance. By contrast, plants constitutively expressing HKT1;1 driven by the cauliflower mosaic virus 35S promoter accumulated high shoot Na+ and grew poorly. Our results demonstrate that the modification of a specific Na+ transport process in specific cell types can reduce shoot Na+ accumulation, an important component of salinity tolerance of many higher plants. PMID:19584143

  3. Na Cauda do Cometa

    NASA Astrophysics Data System (ADS)

    Voelzke, M. R.

    2009-01-01

    Quando viam um cometa, os antigos gregos imaginavam uma estrela com uma vasta cabeleira. Não à toa, a palavra deriva do termo koma, que significa cabelo. Constituídos por fragmentos de gelo e gases, os cometas possuem um núcleo sólido, que pode ter vários quilômetros de diâmetro, e uma cauda que sempre aponta na direção contrária ao Sol, devido aos ventos solares. Graças à aparência de pontos luminosos em movimento (ao contrário de outros astros, que parecem estáticos), esses corpos celestes foram interpretados por diferentes povos com muito misticismo, inspirando mitos tanto de boas-novas como de maus presságios. Conheça algumas dessas histórias:

  4. Large area mercuric iodide photodetectors

    SciTech Connect

    Iwanczyk, J.S.; Dabrowski, A.J.; Markakis, J.M.; Ortale, C.; Schnepple, W.F.

    1984-02-01

    Results of an investigation of large area mercuric iodide (HgI/sub 2/) photodetectors are reported. Different entrance contacts were studied, including semitransparent metallic films and conductive liquids. Theoretical calculations of electronic noise of these photodetectors were compared with experimental results. HgI/sub 2/ photodetectors with active area up to 4 cm/sup 2/ were matched with NaI(Tl) and CsI(Tl) scintillation crystals and were evaluated as gamma-radiation spectrometers. Energy resolution of 9.3% for gamma radiation of 511 keV with a CsI(Tl) scintillator and energy resolution of 9.0% for gamma radiation of 622 keV with a NaI(Tl) scintillator have been obtained.

  5. Deliquescence, efflorescence and ice nucleating ability of NaCl/hydrated NaCl particles under upper tropospheric conditions

    NASA Astrophysics Data System (ADS)

    Wise, M. E.; Baustian, K. J.; Freedman, M. A.; Koop, T.; Tolbert, M. A.

    2010-12-01

    Sea-salt aerosol particles (SSA) are ubiquitous in marine boundary layer and over coastal areas. Therefore SSA have ability to directly and indirectly affect the Earth’s radiation balance. The influence SSA have on the Earth’s radiation balance is related to their water uptake and ice nucleation characteristics. In this study, optical microscopy coupled with Raman spectroscopy was used to determine the deliquescence and efflorescence phase transitions of NaCl particles (a proxy for SSA particles) at temperatures ranging from 233 to 258 K. It was found that NaCl (s) particles deliquesced at 75.7±2.5 % RH and NaCl (aq) particles effloresced at 42.7 ±6.9 % RH. When the temperature of NaCl (aq) particles was held between 236 and 252 K, a mixture of hydrated and non-hydrated particles effloresced. Thus the water uptake characteristics of hydrated NaCl (s) particles were studied. The deliquescence relative humidities (DRH) of hydrated NaCl (s) particles ranged from 75.6 to 94.5 % RH. The DRH values for hydrated NaCl (s) do not agree with the theoretical DRH for the dihydrate form of NaCl (s) particles (the predicted phase using a bulk phase diagram). Additionally, the ice nucleating abilities of NaCl (s) and hydrated NaCl (s) were determined at temperatures ranging from 221 to 230 K. NaCl (s) particles depositionally nucleated ice at an average Sice value of 1.11±0.07. Hydrated NaCl (s) particles depositionally nucleated ice at an average Sice value of 1.01±0.03. When a mixture of hydrated and anhydrous NaCl (s) particles was present in the same sample, ice preferentially nucleated on the hydrated particles 100% of the time. Thus hydrated NaCl (s) particles are better ice nuclei than NaCl (s) particles.

  6. Na+ coordination at the Na2 site of the Na+/I− symporter

    PubMed Central

    Ferrandino, Giuseppe; Nicola, Juan Pablo; Sánchez, Yuly E.; Echeverria, Ignacia; Liu, Yunlong; Amzel, L. Mario; Carrasco, Nancy

    2016-01-01

    The sodium/iodide symporter (NIS) mediates active I− transport in the thyroid—the first step in thyroid hormone biosynthesis—with a 2 Na+: 1 I− stoichiometry. The two Na+ binding sites (Na1 and Na2) and the I− binding site interact allosterically: when Na+ binds to a Na+ site, the affinity of NIS for the other Na+ and for I− increases significantly. In all Na+-dependent transporters with the same fold as NIS, the side chains of two residues, S353 and T354 (NIS numbering), were identified as the Na+ ligands at Na2. To understand the cooperativity between the substrates, we investigated the coordination at the Na2 site. We determined that four other residues—S66, D191, Q194, and Q263—are also involved in Na+ coordination at this site. Experiments in whole cells demonstrated that these four residues participate in transport by NIS: mutations at these positions result in proteins that, although expressed at the plasma membrane, transport little or no I−. These residues are conserved throughout the entire SLC5 family, to which NIS belongs, suggesting that they serve a similar function in the other transporters. Our findings also suggest that the increase in affinity that each site displays when an ion binds to another site may result from changes in the dynamics of the transporter. These mechanistic insights deepen our understanding not only of NIS but also of other transporters, including many that, like NIS, are of great medical relevance. PMID:27562170

  7. Molecular dynamics simulation of dipalmitoylphosphatidylserine bilayer with Na+ counterions.

    PubMed Central

    Pandit, Sagar A; Berkowitz, Max L

    2002-01-01

    We performed a molecular dynamics simulation of dipalmitoylphosphatidylserine (DPPS) bilayer with Na+ counterions. We found that hydrogen bonding between the NH group and the phosphate group leads to a reduction in the area per headgroup when compared to the area in dipalmitoylphosphatidylcholine bilayer. The Na+ ions bind to the oxygen in the carboxyl group of serine, thus giving rise to a dipolar bilayer similar to dipalmitoylphosphatidylethanolamine bilayer. The results of the simulation show that counterions play a crucial role in determining the structural and electrostatic properties of DPPS bilayer. PMID:11916841

  8. Solidification of NaCl-NaF eutectic in space

    NASA Technical Reports Server (NTRS)

    Yue, A. S.; Yu, J. G.

    1974-01-01

    Continuous and discontinuous NaF fibers, embedded in a NaCl matrix, have been produced in space and on earth, respectively. The production of continuous fibers in a eutectic mixture was attributed to the absence of convection current in the liquid during solidification in space. Image transmission and optical transmittance measurements of transverse sections of the space-grown and earth-grown ingots were made with a light microscope and a spectrometer. It was found that better optical properties were obtained from samples grown in space. This was attributed to a better alignment of NaF fibers along the ingot axis.

  9. Encapsulation of Metallic Na in an Electrically Conductive Host with Porous Channels as a Highly Stable Na Metal Anode.

    PubMed

    Luo, Wei; Zhang, Ying; Xu, Shaomao; Dai, Jiaqi; Hitz, Emily; Li, Yiju; Yang, Chunpeng; Chen, Chaoji; Liu, Boyang; Hu, Liangbing

    2017-06-14

    Room-temperature Na ion batteries (NIBs) have attracted great attention because of the widely available, abundant sodium resources and potentially low cost. Currently, the challenge of the NIB development is due primarily to the lack of a high-performance anode, while the Na metal anode holds great promise considering its highest specific capacity of 1165 mA h/g and lowest anodic potential. However, an uneven deposit, relatively infinite volume change, and dendritic growth upon plating/stripping cycles cause a low Coulombic efficiency, poor cycling performance, and severe safety concerns. Here, a stable Na carbonized wood (Na-wood) composite anode was fabricated via a rapid melt infusion (about 5 s) into channels of carbonized wood by capillary action. The channels function as a high-surface-area, conductive, mechanically stable skeleton, which lowers the effective current density, ensures a uniform Na nucleation, and restricts the volume change over cycles. As a result, the Na-wood composite anode exhibited flat plating/stripping profiles with smaller overpotentials and stable cycling performance over 500 h at 1.0 mA/cm(2) in a common carbonate electrolyte system. In sharp comparison, the planar Na metal electrode showed a much shorter cycle life of 100 h under the same test conditions.

  10. Na+ recirculation and isosmotic transport.

    PubMed

    Larsen, E H; Møbjerg, N

    2006-01-01

    The Na(+) recirculation theory for solute-coupled fluid absorption is an expansion of the local osmosis concept introduced by Curran and analyzed by Diamond & Bossert. Based on studies on small intestine the theory assumes that the observed recirculation of Na(+) serves regulation of the osmolarity of the absorbate. Mathematical modeling reproducing bioelectric and hydrosmotic properties of small intestine and proximal tubule, respectively, predicts a significant range of observations such as isosmotic transport, hyposmotic transport, solvent drag, anomalous solvent drag, the residual hydraulic permeability in proximal tubule of AQP1 (-/-) mice, and the inverse relationship between hydraulic permeability and the concentration difference needed to reverse transepithelial water flow. The model reproduces the volume responses of cells and lateral intercellular space (lis) following replacement of luminal NaCl by sucrose as well as the linear dependence of volume absorption on luminal NaCl concentration. Analysis of solvent drag on Na(+) in tight junctions provides explanation for the surprisingly high metabolic efficiency of Na(+) reabsorption. The model predicts and explains low metabolic efficiency in diluted external baths. Hyperosmolarity of lis is governed by the hydraulic permeability of the apical plasma membrane and tight junction with 6-7 mOsm in small intestine and < or = 1 mOsm in proximal tubule. Truly isosmotic transport demands a Na(+) recirculation of 50-70% in small intestine but might be barely measurable in proximal tubule. The model fails to reproduce a certain type of observations: The reduced volume absorption at transepithelial osmotic equilibrium in AQP1 knockout mice, and the stimulated water absorption by gallbladder in diluted external solutions. Thus, it indicates cellular regulation of apical Na(+) uptake, which is not included in the mathematical treatment.

  11. n/a

    NASA Image and Video Library

    2006-12-19

    Photographed from the Space Shuttle Discovery upon its separation from the orbital outpost, the International Space Station (ISS) is shown sporting its new additions. A fly-around gave the crew a look at their handiwork, a new P5 spacer truss segment and a fully retracted P6 solar array wing. Earlier, the STS-116 and Expedition 14 crews concluded eight days of cooperative work onboard the shuttle and station where they accomplished the installation of the newest piece of the station and completely rewired the power grid over the course of four space walks. The station is currently the size of a typical three-bedroom house, with a surface area large enough to cover four basketball courts. The image reflects the latest configuration of the ISS as of December 19, 2006.

  12. Fusion of Na-ASP-2 with human immunoglobulin Fcγ abrogates histamine release from basophils sensitized with anti-Na-ASP-2 IgE.

    PubMed

    Zhan, Bin; Santiago, H; Keegan, B; Gillespie, P; Xue, J; Bethony, J; de Oliveira, L M; Jiang, D; Diemert, D; Xiao, S-H; Jones, K; Feng, X; Hotez, P J; Bottazzi, M E

    2012-01-01

    Na-ASP-2 is a major protein secreted by infective third-stage larvae (L3) of the human hookworm Necator americanus upon host entry. It was chosen as a lead vaccine candidate for its ability to elicit protective immune responses. However, clinical development of this antigen as a recombinant vaccine was halted because it caused allergic reactions among some of human volunteers previously infected with N. americanus. To prevent IgE-mediated allergic reactions induced by Na-ASP-2 but keep its immunogenicity as a vaccine antigen, we designed and tested a genetically engineered fusion protein, Fcγ/Na-ASP-2, composed of full-length Na-ASP-2 and truncated human IgG Fcγ1 that targets the negative signalling receptor FcγRIIb expressed on pro-allergic cells. The chimeric recombinant Fcγ/Na-ASP-2 protein was expressed in Pichia pastoris and shared the similar antigenicity as native Na-ASP-2. Compared to Na-ASP-2, the chimeric fusion protein efficiently reduced the release of histamine in human basophils sensitized with anti-Na-ASP-2 IgE obtained from individuals living in a hookworm-endemic area. In dogs infected with canine hookworm, Fcγ/Na-ASP-2 resulted in significantly reduced immediate-type skin reactivity when injected intradermally compared with Na-ASP-2. Hamsters vaccinated with Fcγ/Na-ASP-2 formulated with Alhydrogel(®) produced specific IgG that recognized Na-ASP-2 and elicited similar protection level against N. americanus L3 challenge as native Na-ASP-2.

  13. High Capacity Na+/H+ Exchange Activity in Mineralizing Osteoblasts

    PubMed Central

    Liu, Li; Schlesinger, Paul H.; Slack, Nicole M.; Friedman, Peter A.; Blair, Harry C.

    2015-01-01

    Osteoblasts synthesize bone in polarized groups of cells sealed by tight junctions. Large amounts of acid are produced as bone mineral is precipitated. We addressed the mechanism by which cells manage this acid load by measuring intracellular pH (pHi) in non-transformed osteoblasts in response to weak acid or bicarbonate loading. Basal pHi in mineralizing osteoblasts was ∼7.3 and decreased by ∼ 1.4 units upon replacing extracellular Na+ with N-methyl-d-glucamine. Loading with 40 mM acetic or propionic acids, in normal extracellular Na+, caused only mild cytosolic acidification. In contrast, in Na+-free solutions, weak acids reduced pHi dramatically. After Na+ reintroduction, pHi recovered rapidly, in keeping with Na+/H+exchanger (NHE) activity. Sodium-dependent pHi recovery from weak acid loading was inhibited by amiloride with the Ki consistent with NHEs. NHE1 and NHE6 were expressed strongly, and expression was upregulated highly, by mineralization, in human osteoblasts. Antibody labeling of mouse bone showed NHE1 on basolateral surfaces of all osteoblasts. NHE6 occurred on basolateral surfaces of osteoblasts mainly in areas of mineralization. Conversely, elevated HCO3- alkalinized osteoblasts, and pH recovered in medium containing CI-, with or without Na+, in keeping with Na+-independent CI-/HCO3- exchange. The exchanger AE2 also occurred on the basolateral surface of osteoblasts, consistent with CI-/HCO3- exchange for elimination of metabolic carbonate. Overexpression of NHE6 or knockdown of NHE1 in MG63 human osteosarcoma cells confirmed roles of NHE1 and NHE6 in maintaining pHi. We conclude that in mineralizing osteoblasts, slightly basic basal pHi is maintained, and external acid load is dissipated, by high-capacity Na+/H+ exchange via NHE1 and NHE6. PMID:21413028

  14. NaOH-modified ceramic honeycomb with enhanced formaldehyde adsorption and removal performance.

    PubMed

    Yu, Jiaguo; Li, Xinyang; Xu, Zhihua; Xiao, Wei

    2013-09-03

    NaOH-modified ceramic honeycombs (Na-CH) were simply prepared by impregnating ceramic honeycombs (CH) into NaOH aqueous solution. It was clearly shown that the surface modification incurs higher specific surface area and smaller grain sizes of the CH without destruction of their integrity. Moreover, the introduced surface NaOH can trigger Cannizzaro disproportionation of surface-absorbed formaldehyde (HCHO) on Na-CH, resulting in catalytic transformation of HCHO into less-toxic formate and methoxy salts. The NaOH concentration during impregnating treatment has a great influence on HCHO adsorption and removal efficiency, while the impregnation time and temperature have little influence on the efficiency. When the CH was impregnated in 1 M NaOH aqueous solution for 0.5 h at room temperature, the HCHO removal efficiency at ambient temperature can reach about 80% with an initial HCHO concentration of 250 ppm. Moreover, the used Na-CH can be facilely regenerated via 1 min blow using a common electric hair dryer, with the generation of less toxic HCOOH and CH3OH and recovery of NaOH. Using such a mild, fast, and practical regeneration method, the regenerated Na-CH showed slight degradation in adsorption and removal capability toward HCHO. The enhanced performance of Na-CH obtained was attributed to the presence of NaOH and increase of specific surface area and surface hydroxyl groups. Considering no demand of noble metal for HCHO removal at ambient temperature and practical reusable capability of Na-CH under mild conditions, this work may provide some new insights into the design and fabrication of advanced catalysts for indoor air purification.

  15. n/a

    NASA Image and Video Library

    1963-01-15

    At its founding, the Marshall Space Flight Center (MSFC) inherited the Army’s Jupiter and Redstone test stands, but much larger facilities were needed for the giant stages of the Saturn V. From 1960 to 1964, the existing stands were remodeled and a sizable new test area was developed. The new comprehensive test complex for propulsion and structural dynamics was unique within the nation and the free world, and they remain so today because they were constructed with foresight to meet the future as well as on going needs. Construction of the S-IC Static test stand complex began in 1961 in the west test area of MSFC, and was completed in 1964. The S-IC static test stand was designed to develop and test the 138-ft long and 33-ft diameter Saturn V S-IC first stage, or booster stage, weighing in at 280,000 pounds. Required to hold down the brute force of a 7,500,000-pound thrust produced by 5 F-1 engines, the S-IC static test stand was designed and constructed with the strength of hundreds of tons of steel and 12,000,000 pounds of cement, planted down to bedrock 40 feet below ground level. The foundation walls, constructed with concrete and steel, are 4 feet thick. The base structure consists of four towers with 40-foot-thick walls extending upward 144 feet above ground level. The structure was topped by a crane with a 135-foot boom. With the boom in the upright position, the stand was given an overall height of 405 feet, placing it among the highest structures in Alabama at the time. In addition to the stand itself, related facilities were constructed during this time. Built directly east of the test stand was the Block House, which served as the control center for the test stand. The two were connected by a narrow access tunnel which housed the cables for the controls. The F-1 Engine test stand was built north of the massive S-IC test stand. The F-1 test stand is a vertical engine firing test stand, 239 feet in elevation and 4,600 square feet in area at the base, and

  16. n/a

    NASA Image and Video Library

    1961-12-11

    At its founding, the Marshall Space Flight Center (MSFC) inherited the Army’s Jupiter and Redstone test stands, but much larger facilities were needed for the giant stages of the Saturn V. From 1960 to 1964, the existing stands were remodeled and a sizable new test area was developed. The new comprehensive test complex for propulsion and structural dynamics was unique within the nation and the free world, and they remain so today because they were constructed with foresight to meet the future as well as on going needs. Construction of the S-IC Static test stand complex began in 1961 in the west test area of MSFC, and was completed in 1964. The S-IC static test stand was designed to develop and test the 138-ft long and 33-ft diameter Saturn V S-IC first stage, or booster stage, weighing in at 280,000 pounds. Required to hold down the brute force of a 7,500,000-pound thrust produced by 5 F-1 engines, the S-IC static test stand was designed and constructed with the strength of hundreds of tons of steel and 12,000,000 pounds of cement, planted down to bedrock 40 feet below ground level. The foundation walls, constructed with concrete and steel, are 4 feet thick. The base structure consists of four towers with 40-foot-thick walls extending upward 144 feet above ground level. The structure was topped by a crane with a 135-foot boom. With the boom in the upright position, the stand was given an overall height of 405 feet, placing it among the highest structures in Alabama at the time. Construction of the S-IC test stand came to a halt at the end of September as the determination was made that the Saturn booster size had to be increased. As a result, the stand had to be modified. With construction delayed, and pumps turned off, this photo, taken December 11, 1961, shows the abandoned site with floods above the 18 ft mark. The flooding was caused by the disturbance of a natural spring months prior during the excavation of the site.

  17. Na Deposition on MnO(100)

    NASA Astrophysics Data System (ADS)

    Feng, Xu; Cox, David F.

    2016-03-01

    Na deposition on the MnO(100) surface was investigated by temperature programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS) and low energy electron diffraction (LEED). Na TPD and XPS results indicate that adsorbed Na interacts strongly with the MnO substrate to form an irreversibly-adsorbed, oxidic Na compound on the surface for coverages up to 1 monolayer (ML). This strongly-bound Na diffuses into the MnO subsurface and bulk at elevated temperatures above 500 K. For Na coverages above 1 ML, metallic Na is present and desorbs from the surface below 500 K. The deposition of Na on MnO(100) follows a Stranski-Krastanov (SK) growth mode, with the formation of metallic Na islands following completion of the first Na monolayer. After Na deposition, the surface exhibits a diffuse (1 × 1) LEED pattern, suggesting the formation of disordered Na overlayers. After heating to 1000 K, the surface presents a (2 × 2) LEED pattern indicating that a surface reconstruction is induced by the diffusion of Na into the near surface region. CO2 can be used as a probe molecule in TPD to distinguish between metallic Na islands and oxidic Na in the first ML, and to indicate when Na that is still observable by XPS goes subsurface.

  18. In search of synaptosomal Na+,K(+)-ATPase regulators.

    PubMed

    Rodríguez de Lores Arnaiz, G

    1992-01-01

    The arrival of the nerve impulse to the nerve endings leads to a series of events involving the entry of sodium and the exit of potassium. Restoration of ionic equilibria of sodium and potassium through the membrane is carried out by the sodium/potassium pump, that is the enzyme Na+,K(+)-ATPase. This is a particle-bound enzyme that concentrates in the nerve ending or synaptosomal membranes. The activity of Na+,K(+)-ATPase is essential for the maintenance of numerous reactions, as demonstrated in the isolated synaptosomes. This lends interest to the knowledge of the possible regulatory mechanisms of Na+,K(+)-ATPase activity in the synaptic region. The aim of this review is to summarize the results obtained in the author's laboratory, that refer to the effect of neurotransmitters and endogenous substances on Na+,K(+)-ATPase activity. Mention is also made of results in the field obtained in other laboratories. Evidence showing that brain Na+,K(+)-ATPase activity may be modified by certain neurotransmitters and insulin have been presented. The type of change produced by noradrenaline, dopamine, and serotonin on synaptosomal membrane Na+,K(+)-ATPase was found to depend on the presence or absence of a soluble brain fraction. The soluble brain fraction itself was able to stimulate or inhibit the enzyme, an effect that was dependent in turn on the time elapsed between preparation and use of the fraction. The filtration of soluble brain fraction through Sephadex G-50 allowed the separation of two active subfractions: peaks I and II. Peak I increased Na+,K(+)- and Mg(2+)-ATPases, and peak II inhibited Na+,K(+)-ATPase. Other membrane enzymes such as acetylcholinesterase and 5'-nucleotidase were unchanged by peaks I or II. In normotensive anesthetized rats, water and sodium excretion were not modified by peak I but were increased by peak II, thus resembling ouabain effects. 3H-ouabain binding was unchanged by peak I but decreased by peak II in some areas of the CNS assayed by

  19. Calmodulin limits pathogenic Na+ channel persistent current

    PubMed Central

    Yan, Haidun; Wang, Chaojian; Marx, Steven O.

    2017-01-01

    Increased “persistent” current, caused by delayed inactivation, through voltage-gated Na+ (NaV) channels leads to cardiac arrhythmias or epilepsy. The underlying molecular contributors to these inactivation defects are poorly understood. Here, we show that calmodulin (CaM) binding to multiple sites within NaV channel intracellular C-terminal domains (CTDs) limits persistent Na+ current and accelerates inactivation across the NaV family. Arrhythmia or epilepsy mutations located in NaV1.5 or NaV1.2 channel CTDs, respectively, reduce CaM binding either directly or by interfering with CTD–CTD interchannel interactions. Boosting the availability of CaM, thus shifting its binding equilibrium, restores wild-type (WT)–like inactivation in mutant NaV1.5 and NaV1.2 channels and likewise diminishes the comparatively large persistent Na+ current through WT NaV1.6, whose CTD displays relatively low CaM affinity. In cerebellar Purkinje neurons, in which NaV1.6 promotes a large physiological persistent Na+ current, increased CaM diminishes the persistent Na+ current, suggesting that the endogenous, comparatively weak affinity of NaV1.6 for apoCaM is important for physiological persistent current. PMID:28087622

  20. Astrocytes generate Na+-mediated metabolic waves.

    PubMed

    Bernardinelli, Yann; Magistretti, Pierre J; Chatton, Jean-Yves

    2004-10-12

    Glutamate-evoked Na+ increase in astrocytes has been identified as a signal coupling synaptic activity to glucose consumption. Astrocytes participate in multicellular signaling by transmitting intercellular Ca2+ waves. Here we show that intercellular Na+ waves are also evoked by activation of single cultured cortical mouse astrocytes in parallel with Ca2+ waves; however, there are spatial and temporal differences. Indeed, maneuvers that inhibit Ca2+ waves also inhibit Na+ waves; however, inhibition of the Na+/glutamate cotransporters or enzymatic degradation of extracellular glutamate selectively inhibit the Na+ wave. Thus, glutamate released by a Ca2+ wave-dependent mechanism is taken up by the Na+/glutamate cotransporters, resulting in a regenerative propagation of cytosolic Na+ increases. The Na+ wave gives rise to a spatially correlated increase in glucose uptake, which is prevented by glutamate transporter inhibition. Therefore, astrocytes appear to function as a network for concerted neurometabolic coupling through the generation of intercellular Na+ and metabolic waves.

  1. The NA62 trigger system

    NASA Astrophysics Data System (ADS)

    Krivda, M.; NA62 Collaboration

    2013-08-01

    The main aim of the NA62 experiment (NA62 Technical Design Report, na62.web.cern.ch/NA62/Documents/TD_Full_doc_v1.pdf> [1]) is to study ultra-rare Kaon decays. In order to select rare events over the overwhelming background, central systems with high-performance, high bandwidth, flexibility and configurability are necessary, that minimize dead time while maximizing data collection reliability. The NA62 experiment consists of 12 sub-detector systems and several trigger and control systems, for a total channel count of less than 100,000. The GigaTracKer (GTK) has the largest number of channels (54,000), and the Liquid Krypton (LKr) calorimeter shares with it the largest raw data rate (19 GB/s). The NA62 trigger system works with 3 trigger levels. The first trigger level is based on a hardware central trigger unit, so-called L0 Trigger Processor (L0TP), and Local Trigger Units (LTU), which are all located in the experimental cavern. Other two trigger levels are based on software, and done with a computer farm located on surface. The L0TP receives information from triggering sub-detectors asynchronously via Ethernet; it processes the information, and then transmits a final trigger decision synchronously to each sub-detector through the Trigger and Timing Control (TTC) system. The interface between L0TP and the TTC system, which is used for trigger and clock distribution, is provided by the Local Trigger Unit board (LTU). The LTU can work in two modes: global and stand-alone. In the global mode, the LTU provides an interface between L0TP and TTC system. In the stand-alone mode, the LTU can fully emulate L0TP and so provides an independent way for each sub-detector for testing or calibration purposes. In addition to the emulation functionality, a further functionality is implemented that allows to synchronize the clock of the LTU with the L0TP and the TTC system. For testing and debugging purposes, a Snap Shot Memory (SSM) interface is implemented, that can work

  2. Europlanet NA2 Science Networking

    NASA Astrophysics Data System (ADS)

    Harri, Ari-Matti; Szego, Karoly; Genzer, Maria; Schmidt, Walter; Krupp, Norbert; Lammer, Helmut; Kallio, Esa; Haukka, Harri

    2013-04-01

    Europlanet RI / NA2 Science Networking [1] focused on determining the major goals of current and future European planetary science, relating them to the Research Infrastructure that the Europlanet RI project [2] developed, and placing them in a more global context. NA2 also enhanced the ability of European planetary scientists to participate on the global scene with their own agenda-setting projects and ideas. The Networking Activity NA2 included five working groups, aimed at identifying key science issues and producing reference books on major science themes that will bridge the gap between the results of present and past missions and the scientific preparation of the future ones. Within the Europlanet RI project (2009-2012) the NA2 and NA2-WGs organized thematic workshops, an expert exchange program and training groups to improve the scientific impact of this Infrastructure. The principal tasks addressed by NA2 were: • Science activities in support to the optimal use of data from past and present space missions, involving the broad planetary science community beyond the "space club" • Science activities in support to the preparation of future planetary missions: Earth-based preparatory observations, laboratory studies, R&D on advanced instrumentation and exploration technologies for the future, theory and modeling etc. • Develop scientific activities, joint publications, dedicated meetings, tools and services, education activities, engaging the public and industries • Update science themes and addressing the two main scientific objectives • Prepare and support workshops of the International Space Science Institute (ISSI) in Bern and • Support Trans National Activities (TNAs), Joined Research Activities (JRAs) and the Integrated and Distributed Information Service (IDIS) of the Europlanet project These tasks were achieved by WG workshops organized by the NA2 working groups, by ISSI workshops and by an Expert Exchange Program. There were 17 official WG

  3. Sodium iron hexacyanoferrate with high Na content as a Na-rich cathode material for Na-ion batteries

    SciTech Connect

    You, Ya; Yu, Xi -Qian; Yin, Ya -Xia; Nam, Kyung -Wan; Guo, Yu -Guo

    2014-10-27

    Owing to the worldwide abundance and low-cost of Na, room-temperature Na-ion batteries are emerging as attractive energy storage systems for large-scale grids. Increasing the Na content in cathode material is one of the effective ways to achieve high energy density. Prussian blue and its analogues (PBAs) are promising Na-rich cathode materials since they can theoretically store two Na ions per formula. However, increasing the Na content in PBAs cathode materials is a big challenge in the current. Here we show that sodium iron hexacyanoferrate with high Na content could be obtained by simply controlling the reducing agent and reaction atmosphere during synthesis. The Na content can reach as high as 1.63 per formula, which is the highest value for sodium iron hexacyanoferrate. This Na-rich sodium iron hexacyanoferrate demonstrates a high specific capacity of 150 mA h g-1 and remarkable cycling performance with 90% capacity retention after 200 cycles. Furthermore, the Na intercalation/de-intercalation mechanism is systematically studied by in situ Raman, X-ray diffraction and X-ray absorption spectroscopy analysis for the first time. As a result, the Na-rich sodium iron hexacyanoferrate could function as a plenteous Na reservoir and has great potential as a cathode material toward practical Na-ion batteries.

  4. Sodium iron hexacyanoferrate with high Na content as a Na-rich cathode material for Na-ion batteries

    DOE PAGES

    You, Ya; Yu, Xi -Qian; Yin, Ya -Xia; ...

    2014-10-27

    Owing to the worldwide abundance and low-cost of Na, room-temperature Na-ion batteries are emerging as attractive energy storage systems for large-scale grids. Increasing the Na content in cathode material is one of the effective ways to achieve high energy density. Prussian blue and its analogues (PBAs) are promising Na-rich cathode materials since they can theoretically store two Na ions per formula. However, increasing the Na content in PBAs cathode materials is a big challenge in the current. Here we show that sodium iron hexacyanoferrate with high Na content could be obtained by simply controlling the reducing agent and reaction atmospheremore » during synthesis. The Na content can reach as high as 1.63 per formula, which is the highest value for sodium iron hexacyanoferrate. This Na-rich sodium iron hexacyanoferrate demonstrates a high specific capacity of 150 mA h g-1 and remarkable cycling performance with 90% capacity retention after 200 cycles. Furthermore, the Na intercalation/de-intercalation mechanism is systematically studied by in situ Raman, X-ray diffraction and X-ray absorption spectroscopy analysis for the first time. As a result, the Na-rich sodium iron hexacyanoferrate could function as a plenteous Na reservoir and has great potential as a cathode material toward practical Na-ion batteries.« less

  5. Ionic regulation of Na absorption in proximal colon: cation inhibition of electroneutral Na absorption

    SciTech Connect

    Sellin, J.H.; De Soignie, R.

    1987-01-01

    Active Na absorption (J/sub net//sup NA/) in rabbit proximal colon in vitro is paradoxically stimulated as (Na) in the bathing media is lowered with constant osmolarity. J/sub m..-->..s//sup Na/ increases almost linearly from 0 to 50 mM (Na)/sub 0/ but then plateaus and actually decreases from 50 to 140 mM (Na)/sub 0/, consistent with inhibition of an active transport process. Both lithium and Na are equally effective inhibitors of J/sub net//sup Na/, whereas choline and mannitol do not block the high rate of J/sub net//sup Na/ observed in decreased (Na)/sub 0/. Either gluconate or proprionate replacement of Cl inhibits J/sub net//sup Na/. J/sub net//sup Na/ at lowered (Na)/sub 0/ is electrically silent and is accompanied by increased Cl absorption; it is inhibited by 10/sup -3/ M amiloride and 10/sup -3/ theophylline but not by 10/sup -4/ M bumetanide. Epinephrine is equally effective at stimulating Na absorption at 50 and 140 mM (Na). Na gradient experiments are consistent with a predominantly serosal effect of the decreased (Na)/sub 0/. These results suggest that 1) Na absorption in rabbit proximal colon in vitro is stimulated by decreased (Na); 2) the effect is cation specific, both Na and Li blocking the stimulatory effect; 3) the transport is mediated by Na-H exchange and is Cl dependent but 4) is under different regulatory mechanisms than the epinephrine-sensitive Na-Cl cotransport previously described in proximal colon. Under the appropriate conditions, proximal colon absorbs Na extremely efficiently. Na-H exchange in this epithelium is cation inhibitable, either directly or by a secondary regulatory process.

  6. Deliquescence of NaCl-NaNO3 and KNO3-NaNO3 Salt Mixtures at 90C

    SciTech Connect

    Carroll, S; Craig, L; Wolery, T

    2003-12-29

    We conducted reversed deliquescence experiments in saturated NaCl-NaNO3-H2O and KNO{sub 3}-NaNO{sub 3}-H{sub 2}O systems at 90 C to determine relative humidity and solution composition. NaCl, NaNO{sub 3}, and KNO{sub 3} represent members of dust salt assemblages that are likely to deliquesce and form concentrated brines on high-level radioactive waste package surfaces in a repository environment at Yucca Mountain, NV, USA. Model predictions agree with experimental results for the NaCl-NaNO{sub 3}-H{sub 2}O system, but underestimate relative humidity by as much as 8% and solution composition by as much as 50% in the KNO{sub 3}-NaNO{sub 3}-H{sub 2}O system.

  7. Na+ Tolerance and Na+ Transport in Higher Plants

    PubMed Central

    TESTER, MARK; DAVENPORT, ROMOLA

    2003-01-01

    Tolerance to high soil [Na+] involves processes in many different parts of the plant, and is manifested in a wide range of specializations at disparate levels of organization, such as gross morphology, membrane transport, biochemistry and gene transcription. Multiple adaptations to high [Na+] operate concurrently within a particular plant, and mechanisms of tolerance show large taxonomic variation. These mechanisms can occur in all cells within the plant, or can occur in specific cell types, reflecting adaptations at two major levels of organization: those that confer tolerance to individual cells, and those that contribute to tolerance not of cells per se, but of the whole plant. Salt‐tolerant cells can contribute to salt tolerance of plants; but we suggest that equally important in a wide range of conditions are processes involving the management of Na+ movements within the plant. These require specific cell types in specific locations within the plant catalysing transport in a coordinated manner. For further understanding of whole plant tolerance, we require more knowledge of cell‐specific transport processes and the consequences of manipulation of transporters and signalling elements in specific cell types. PMID:12646496

  8. Optical measurements of Na-Ca-K exchange currents in intact outer segments isolated from bovine retinal rods

    PubMed Central

    1991-01-01

    The properties of Na-Ca-K exchange current through the plasma membrane of intact rod outer segments (ROS) isolated from bovine retinas were studied with the optical probe neutral red. Small cellular organelles such as bovine ROS do not offer an adequate collecting area to measure Na-Ca-K exchange currents with electrophysiological techniques. This study demonstrates that Na-Ca-K exchange current in bovine ROS can be measured with the dye neutral red and dual-wavelength spectrophotometry. The binding of neutral red is sensitive to transport of cations across the plasma membrane of ROS by the effect of the translocated cations on the surface potential of the intracellular disk membranes (1985. J. Membr. Biol. 88: 249-262). Electrogenic Na+ fluxes through the ROS plasma membrane were measured with a resolution of 10(5) Na+ ions/ROS per s, equivalent to a current of approximately 0.01 pA; maximal electrogenic Na-Ca-K exchange flux in bovine ROS was equivalent to a maximal exchange current of 1-2 pA. Electrogenic Na+ fluxes were identified as Na-Ca-K exchange current based on a comparison between electrogenic Na+ flux and Na(+)-stimulated Ca2+ release with respect to flux rate, Na+ dependence, and ion selectivity. Neutral red monitored the net entry of a single positive charge carried by Na+ for each Ca2+ ion released (i.e., monitored the Na-Ca-K exchange current). Na-Ca-K exchange in the plasma membrane of bovine ROS had the following properties: (a) Inward Na-Ca-K exchange current required internal Ca2+ (half-maximal stimulation at a free Ca2+ concentration of 0.9 microM), whereas outward Na-Ca-K exchange current required both external Ca2+ (half-maximal stimulation at a free Ca2+ concentration of 1.1 microM) and external K+. (b) Inward Na-Ca-K exchange current depended in a sigmoidal manner on the external Na+ concentration, identical to Na(+)-stimulated Ca2+ release measured with Ca(2+)- indicating dyes. (c) The neutral red method was modified to measure Ca(2

  9. Self-assembled cabbage-like NaInS2 microstructures with efficient visible light photocatalytic performance

    NASA Astrophysics Data System (ADS)

    Gao, Yuanhao; Zhai, Xuezhen; Zhang, Yange; Xu, Zhihong; Li, Pinjiang; Zheng, Zhi

    2013-07-01

    Cabbage-like NaInS2 microstructures have been synthesized by reacting In(NO3)3 with the alkaline sulfur aqueous solution of NaOH in a simple hydrothermal process without any shape-directing surfactants. The cabbage-like NaInS2 architectures are monodispersed in large quantities. The cabbage-like morphologies depend strongly on the different ratios of S powder to NaOH, the reaction temperature and reaction time. The possible growth mechanism for the formation of cabbage-like NaInS2 architectures is discussed. The cabbage-like NaInS2 architectures exhibit the superiority of photocatalytic performance for the photodegradation of RhB irradiation under visible light irradiation. It is believed that the photocatalytic superiority of the cabbage-like NaInS2 architectures is mainly due to their special surface areas and inner interconnected structural features.

  10. Generalized urticaria induced by the Na-ASP-2 hookworm vaccine: implications for the development of vaccines against helminths.

    PubMed

    Diemert, David J; Pinto, Antonio G; Freire, Janaina; Jariwala, Amar; Santiago, Helton; Hamilton, Robert G; Periago, Maria Victoria; Loukas, Alex; Tribolet, Leon; Mulvenna, Jason; Correa-Oliveira, Rodrigo; Hotez, Peter J; Bethony, Jeffrey M

    2012-07-01

    Necator americanus Ancylostoma-secreted protein 2 (Na-ASP-2) is secreted by infective hookworm larvae on entry into human hosts. Vaccination of laboratory animals with recombinant Na-ASP-2 provides significant protection against challenge infections. In endemic areas antibodies to Na-ASP-2 are associated with reduced risk of heavy N americanus infections. To assess the safety and immunogenicity of recombinant Na-ASP-2 adjuvanted with Alhydrogel in healthy Brazilian adults previously infected with N americanus. Participants were randomized to receive Na-ASP-2 or hepatitis B vaccine. Major IgG and IgE epitopes of the Na-ASP-2 molecule were mapped by using sera from these same subjects. Seroepidemiologic studies in adults and children residing in hookworm-endemic areas were conducted to assess the prevalence of IgE responses to Na-ASP-2. Vaccination with a single dose of Na-ASP-2 resulted in generalized urticarial reactions in several volunteers. These reactions were associated with pre-existing Na-ASP-2-specific IgE likely induced by previous hookworm infection. Surveys revealed that a significant proportion of the population in hookworm-endemic areas had increased levels of IgE to Na-ASP-2. Epitope mapping demonstrated sites on the Na-ASP-2 molecule that are uniquely or jointly recognized by IgG and IgE antibodies. Infection with N americanus induces increased levels of total and specific IgE to Na-ASP-2 that result in generalized urticaria on vaccination with recombinant Na-ASP-2. These data advance knowledge of vaccine development for helminths given their propensity to induce strong T(H)2 responses. Study data highlight the important differences between the immune responses to natural helminth infection and to vaccination with a recombinant helminth antigen. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  11. 78 FR 10100 - Data Specifications for Collecting Study Area Boundaries

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-13

    ... COMMISSION 47 CFR Part 54 Data Specifications for Collecting Study Area Boundaries AGENCY: Federal... Boundary Data Reporting in Esri Shapefile Format, DA 12-1777. Form Number: N/A. Respondents: Incumbent... changes to study area boundaries; biannually for recertification or previously submitted data. Obligation...

  12. Compensatory regulation of Na+ absorption by Na+/H+ exchanger and Na+-Cl- cotransporter in zebrafish (Danio rerio)

    PubMed Central

    2013-01-01

    Introduction In mammals, internal Na+ homeostasis is maintained through Na+ reabsorption via a variety of Na+ transport proteins with mutually compensating functions, which are expressed in different segments of the nephrons. In zebrafish, Na+ homeostasis is achieved mainly through the skin/gill ionocytes, namely Na+/H+ exchanger (NHE3b)-expressing H+-ATPase rich (HR) cells and Na+-Cl- cotransporter (NCC)-expressing NCC cells, which are functionally homologous to mammalian proximal and distal convoluted tubular cells, respectively. The present study aimed to investigate whether or not the functions of HR and NCC ionocytes are differentially regulated to compensate for disruptions of internal Na+ homeostasis and if the cell differentiation of the ionocytes is involved in this regulation pathway. Results Translational knockdown of ncc caused an increase in HR cell number and a resulting augmentation of Na+ uptake in zebrafish larvae, while NHE3b loss-of-function caused an increase in NCC cell number with a concomitant recovery of Na+ absorption. Environmental acid stress suppressed nhe3b expression in HR cells and decreased Na+ content, which was followed by up-regulation of NCC cells accompanied by recovery of Na+ content. Moreover, knockdown of ncc resulted in a significant decrease of Na+ content in acid-acclimated zebrafish. Conclusions These results provide evidence that HR and NCC cells exhibit functional redundancy in Na+ absorption, similar to the regulatory mechanisms in mammalian kidney, and suggest this functional redundancy is a critical strategy used by zebrafish to survive in a harsh environment that disturbs body fluid Na+ homeostasis. PMID:23924428

  13. The hydrogen storage properties of Na decorated small boron cluster B6Na8

    NASA Astrophysics Data System (ADS)

    Tang, Chunmei; Wang, Zhiguo; Zhang, Xue; Wen, Ninghua

    2016-09-01

    The binding energy of the Na atoms to the hollow sites of the B6 cage is larger than the experimental cohesive energy of bulk Na, so the clustering of Na atoms can be avoided. The polarization interaction dominates the adsorption of H2 by the B6Na8 cluster. The Na-coated B6Na8sbnd B8sbnd B6Na8 complex with the dispersive Na atoms and four H2 molecules adsorbed per Na can serve as better building blocks of polymers than the (B6Na8)2 dimer. These findings suggest a new route to design cluster-assembled hydrogen storage materials based on sp2-terminated boron chains.

  14. Conversion and Distribution of Lead and Tin in NaOH-NaNO3 Fusion Process

    NASA Astrophysics Data System (ADS)

    Liu, Jingxin; Guo, Xueyi

    2016-12-01

    Oxidizing alkali fusion process has been studied to extract amphoteric metals. Transformation and distribution behaviors of typical amphoteric metals Pb and Sn in the NaOH-NaNO3 fusion process are systemically studied by theoretical analysis and experimental verification done in this work. Functions of NaOH and NaNO3 in the fusion process were also investigated. The results show the fused products, Na2PbO3 and Na2SnO3, are captured in the flux, and Na2PbO4 is speculated to reduce to Pb(II) in the following leaching process. By measuring solubility data of NaOH-Na2SnO3-PbO-H2O system, a strategy of crystallization is proposed to separate Sn with Pb in concentrated alkaline solution, and slice Na2Sn(OH)6 is obtained as a product.

  15. Conversion and Distribution of Lead and Tin in NaOH-NaNO3 Fusion Process

    NASA Astrophysics Data System (ADS)

    Liu, Jingxin; Guo, Xueyi

    2017-04-01

    Oxidizing alkali fusion process has been studied to extract amphoteric metals. Transformation and distribution behaviors of typical amphoteric metals Pb and Sn in the NaOH-NaNO3 fusion process are systemically studied by theoretical analysis and experimental verification done in this work. Functions of NaOH and NaNO3 in the fusion process were also investigated. The results show the fused products, Na2PbO3 and Na2SnO3, are captured in the flux, and Na2PbO4 is speculated to reduce to Pb(II) in the following leaching process. By measuring solubility data of NaOH-Na2SnO3-PbO-H2O system, a strategy of crystallization is proposed to separate Sn with Pb in concentrated alkaline solution, and slice Na2Sn(OH)6 is obtained as a product.

  16. Concentration and precipitation of NaCl and KCl from salt cake leach solutions by electrodialysis

    SciTech Connect

    Sreenivasarao, K; Patsiogiannis, F.; Hryn, J.N.

    1997-02-09

    Electrodialysis was investigated for cost-effective recovery of salt from salt cake leach solutions. (Salt cake is a waste stream generated by the aluminum industry during treatment of aluminum drosses and scrap.) We used a pilot-scale electrodialysis stack of 5 membrane pairs, each with an effective area of 0.02 m{sup 2}. The diluate stream contained synthetic NaCl, KCl,mixtures of NaCl and KCl, and actual salt cake leach solutions (mainly NaCl and KCl, with small amounts of MgCl{sub 2}). We concentrated and precipitated NaCl and KCl salts from the concentrate steam when the initial diluate stream concentration was 21.5 to 28.8 wt% NaCl and KCl. We found that water transferring through the membranes was a significant factor in overall efficiency of salt recovery by electrodialysis.

  17. Growth mechanism and magnetic and electrochemical properties of Na{sub 0.44}MnO{sub 2} nanorods as cathode material for Na-ion batteries

    SciTech Connect

    Demirel, S.; Oz, E.; Altin, E.; Altin, S.; Bayri, A.; Kaya, P.; Turan, S.; Avci, S.

    2015-07-15

    Nanorods of Na{sub 0.44}MnO{sub 2} are a promising cathode material for Na-ion batteries due to their large surface area and single crystalline structure. We report the growth mechanism of Na{sub 0.44}MnO{sub 2} nanorods via solid state synthesis and their physical properties. The structure and the morphology of the Na{sub 0.44}MnO{sub 2} nanorods are investigated by X-ray diffraction (XRD), scanning and tunneling electron microscopy (SEM and TEM), and energy-dispersive X-ray (EDX) techniques. The growth mechanism of the rods is investigated and the effects of vapor pressure and partial melting of Na-rich regions are discussed. The magnetic measurements show an antiferromagnetic phase transition at 25 K and the μ{sub eff} is determined as 3.41 and 3.24 μ{sub B} from the χ–T curve and theoretical calculation, respectively. The electronic configuration and spin state of Mn{sup 3+} and Mn{sup 4+} are discussed in detail. The electrochemical properties of the cell fabricated using the nanorods are investigated and the peaks in the voltammogram are attributed to the diffusion of Na ions from different sites. Na intercalation process is explained by one and two Margules and van Laar models. - Highlights: • We synthesized Na{sub 0.44}MnO{sub 2} nanorods via a simple solid state reaction technique. • Our studies show that excess Na plays a crucial role in the nanorod formation. • Magnetization measurements show that Mn{sup 3+} ions are in LS and HS states. • The electrochemical properties of the cell fabricated using the nanorods are investigated. • Na intercalation process is explained by one and two Margules and van Laar models.

  18. A long-life Na-air battery based on a soluble NaI catalyst.

    PubMed

    Yin, Wen-Wen; Shadike, Zulipiya; Yang, Yin; Ding, Fei; Sang, Lin; Li, Hong; Fu, Zheng-Wen

    2015-02-11

    A Na-air battery with NaI dissolved in a typical organic electrolyte could run up to 150 cycles with a capacity limit of 1000 mA h g(-1). The low charge voltage plateau of 3.2 V vs. Na(+)/Na in a Na-air battery should mainly be attributed to the oxidation reaction of active iodine anions.

  19. Silicene for Na-ion battery applications

    NASA Astrophysics Data System (ADS)

    Zhu, Jiajie; Schwingenschlögl, Udo

    2016-09-01

    Na-ion batteries are promising candidates to replace Li-ion batteries in large scale applications because of the advantages in natural abundance and cost of Na. Silicene has potential as the anode in Li-ion batteries but so far has not received attention with respect to Na-ion batteries. In this context, freestanding silicene, a graphene-silicene-graphene heterostructure, and a graphene-silicene superlattice are investigated for possible application in Na-ion batteries, using first-principles calculations. The calculated Na capacities of 954 mAh/g for freestanding silicene and 730 mAh/g for the graphene-silicene superlattice (10% biaxial tensile strain) are highly competitive and potentials of \\gt 0.3 {{V}} against the Na{}+/Na potential exceed the corresponding value of graphite. In addition, the diffusion barriers are predicted to be \\lt 0.3 {eV}.

  20. Kinetic Analysis of H(+)-Na(+) Selectivity in a Light-Driven Na(+)-Pumping Rhodopsin.

    PubMed

    Kato, Yoshitaka; Inoue, Keiichi; Kandori, Hideki

    2015-12-17

    Krokinobacter eikastus rhodopsin 2 (KR2) is a recently identified light-driven Na(+) pump from a marine bacterium. KR2 pumps Na(+) in NaCl solution but pumps H(+) in the absence of Na(+) and Li(+). The Na(+) transport mechanism in KR2 has been extensively studied, whereas understanding of the H(+) transport mechanism is very limited. Here we studied ion uptake mechanisms and H(+)-Na(+) selectivity using flash photolysis. The results show that decay of the blue-shifted M intermediate is dependent on both [Na(+)] and [H(+)], indicating that KR2 competitively uptakes Na(+) or H(+) upon M decay. Comprehensive concentration dependence of Na(+) and H(+) revealed that the rate constant of H(+) uptake (kH) was much larger than that of Na(+) uptake (kNa) with a ratio (kH/kNa) of >10(3). Therefore, KR2 pumps only H(+) when Na(+) and H(+) concentrations are similar. On the contrary, KR2 pumps Na(+) exclusively under physiological conditions in which [Na(+)] is much greater than [H(+)].

  1. MgO-templated carbon as a negative electrode material for Na-ion capacitors

    NASA Astrophysics Data System (ADS)

    Kado, Yuya; Soneda, Yasushi

    2016-12-01

    In this study, MgO-templated carbon with different pore structures was investigated as a negative electrode material for Na-ion capacitors. With increasing the Brunauer-Emmett-Teller surface area, the irreversible capacity increased, and the coulombic efficiency of the 1st cycle decreased because of the formation of solid electrolyte interface layers. MgO-templated carbon annealed at 1000 °C exhibited the highest capacity and best rate performance, suggesting that an appropriate balance between surface area and crystallinity is imperative for fast Na-ion storage, attributed to the storage mechanism: combination of non-faradaic electric double-layer capacitance and faradaic Na intercalation in the carbon layers. Finally, a Na-ion capacitor cell using MgO-templated carbon and activated carbon as the negative and positive electrodes, respectively, exhibited an energy density at high power density significantly greater than that exhibited by the cell using a commercial hard carbon negative electrode.

  2. Spectral induced polarization of Na-montmorillonite dispersions.

    PubMed

    Leroy, Philippe; Weigand, Maximilian; Mériguet, Guillaume; Zimmermann, Egon; Tournassat, Christophe; Fagerlund, Fritjof; Kemna, Andreas; Huisman, Johan Alexander

    2017-11-01

    Montmorillonite (Mt) clays have a high specific surface area and surface charge, which confer them remarkable adsorption properties. Nevertheless, their electrochemical and aggregation behavior are not completely elucidated because of the complexity of their microstructural and interfacial properties. In this work, the conductive and dispersive properties of Na-Mt suspensions of weight fractions 0.5-5.2% were investigated for the first time using the spectral induced polarization method. A four-electrode system was used to reduce errors introduced by electrode polarization and contact resistances. Complex conductivity spectra in the low-frequency range of 0.1Hz to 45kHz were successfully described using a triple layer model of the basal surface of Mt and a complex conductivity model that considers conduction of the diffuse layer and polarization of the Stern layer. Aggregate size distributions were inferred from inverted relaxation time distributions. We found that the negative and permanent surface charge of the basal plane of Na-Mt controls its quadrature (imaginary) conductivity, which is not very sensitive to pH and salinity (NaCl) in the 100Hz to 45kHz frequency range. For lower frequencies, the sudden increase of the quadrature conductivity at the highest salinities was explained by considering coagulation of Na-Mt particles. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Functional and operational design requirements for decontamination and decommissioning of the EBR-I Mark-II NaK: Final report. [NaK eutectics

    SciTech Connect

    Brown, B.W.; Crandall, D.L.; Dafoe, R.E.; Dolenc, M.R.; LaRue, D.M.

    1987-09-01

    Approximately 180 gal of sodium/potassium (NaK) eutectic liquid metal were severely radioactively contaminated during a meltdown of the Mark-II core of the Experimental Breeder Reactor-I (EBR-I) in November 1955. This contaminated NaK, which is contained in four vessels, is currently stored in an underground bunker located at the Army Reentry Vehicle Facility Site (ARVFS) located approximately at the center of the Idaho National Engineering Laboratory (INEL). This document presents the Functional and Operational Requirements (F and ORs) for the D and D of the contaminated NaK and the ARVFS bunker site. This project will chemically deactivate the NaK; dispose of the radioactively contaminated product at a designated burial site; chemically deactivate any residual NaK in the containers, and dispose of the containers at a designated burial site; decontaminate and decommission any contaminated process equipment used in these operations, and decontaminate and decommission the ARVFS bunker site. Completion of the above technical objectives will allow for the effective disposition of the NaK, and will return the ARFVS bunker and immediate area to a reusable condition. Upon completion, the ARVFS NaK, which is now considered a significant potential hazard, will be removed from the Surplus Facilities Management Program priority listing of projects. 33 refs., 8 figs.

  4. Structural effects of 34Na in the 33Na(n ,γ )34Na radiative capture reaction

    NASA Astrophysics Data System (ADS)

    Singh, G.; Shubhchintak, Chatterjee, R.

    2017-06-01

    Background: The path towards the production of r -process seed nuclei follows a course where the neutron rich light and medium mass nuclei play a crucial role. The neutron capture rates for these exotic nuclei could dominate over their α -capture rates, thereby enhancing their abundances at or near the drip line. Sodium isotopes especially should have a strong neutron capture flow to gain abundance at the drip line. In this context, study of 33Na(n ,γ )34Na and 33Na(α ,n )36Al reactions becomes indispensable. Purpose: In this paper, we calculate the radiative neutron capture cross section for the 33Na(n ,γ )34Na reaction involving deformation effects. Subsequently, the rate for this reaction is found and compared with that of the α -capture for the 33Na(α ,n )36Al reaction to determine the possible path flow for the abundances of sodium isotopes. Method: We use the entirely quantum mechanical theory of finite-range distorted-wave Born approximation upgraded to incorporate deformation effects, and calculate the Coulomb dissociation of 34Na as it undergoes elastic breakup on 208Pb when directed at a beam energy of 100 MeV/u. Using the principle of detailed balance to study the reverse photodisintegration reaction, we find the radiative neutron capture cross section with variation in one-neutron binding energy and quadrupole deformation of 34Na. The rate of this 33Na(n ,γ )34Na reaction is then compared with that of the α -capture by 33Na deduced from the Hauser-Feshbach theory. Results: The nonresonant one-neutron radiative capture cross section for 33Na(n ,γ )34Na is calculated and is found to increase with increasing deformation of 34Na. An analytic scrutiny of the capture cross section with neutron separation energy as a parameter is also done at different energy ranges. The calculated reaction rate is compared with the rate of the 33Na(α ,n )36Al reaction, and is found to be significantly higher below a temperature of T9=2 . Conclusion: At the

  5. Slow [Na+]i dynamics impacts arrhythmogenesis and spiral wave reentry in cardiac myocyte ionic model

    NASA Astrophysics Data System (ADS)

    Krogh-Madsen, Trine; Christini, David J.

    2017-09-01

    Accumulation of intracellular Na+ is gaining recognition as an important regulator of cardiac myocyte electrophysiology. The intracellular Na+ concentration can be an important determinant of the cardiac action potential duration, can modulate the tissue-level conduction of excitation waves, and can alter vulnerability to arrhythmias. Mathematical models of cardiac electrophysiology often incorporate a dynamic intracellular Na+ concentration, which changes much more slowly than the remaining variables. We investigated the dependence of several arrhythmogenesis-related factors on [Na+]i in a mathematical model of the human atrial action potential. In cell simulations, we found that [Na+]i accumulation stabilizes the action potential duration to variations in several conductances and that the slow dynamics of [Na+]i impacts bifurcations to pro-arrhythmic afterdepolarizations, causing intermittency between different rhythms. In long-lasting tissue simulations of spiral wave reentry, [Na+]i becomes spatially heterogeneous with a decreased area around the spiral wave rotation center. This heterogeneous region forms a functional anchor, resulting in diminished meandering of the spiral wave. Our findings suggest that slow, physiological, rate-dependent variations in [Na+]i may play complex roles in cellular and tissue-level cardiac dynamics.

  6. Slow [Na(+)]i dynamics impacts arrhythmogenesis and spiral wave reentry in cardiac myocyte ionic model.

    PubMed

    Krogh-Madsen, Trine; Christini, David J

    2017-09-01

    Accumulation of intracellular Na(+) is gaining recognition as an important regulator of cardiac myocyte electrophysiology. The intracellular Na(+) concentration can be an important determinant of the cardiac action potential duration, can modulate the tissue-level conduction of excitation waves, and can alter vulnerability to arrhythmias. Mathematical models of cardiac electrophysiology often incorporate a dynamic intracellular Na(+) concentration, which changes much more slowly than the remaining variables. We investigated the dependence of several arrhythmogenesis-related factors on [Na(+)]i in a mathematical model of the human atrial action potential. In cell simulations, we found that [Na(+)]i accumulation stabilizes the action potential duration to variations in several conductances and that the slow dynamics of [Na(+)]i impacts bifurcations to pro-arrhythmic afterdepolarizations, causing intermittency between different rhythms. In long-lasting tissue simulations of spiral wave reentry, [Na(+)]i becomes spatially heterogeneous with a decreased area around the spiral wave rotation center. This heterogeneous region forms a functional anchor, resulting in diminished meandering of the spiral wave. Our findings suggest that slow, physiological, rate-dependent variations in [Na(+)]i may play complex roles in cellular and tissue-level cardiac dynamics.

  7. Revisiting the hydration structure of aqueous Na+

    NASA Astrophysics Data System (ADS)

    Galib, M.; Baer, M. D.; Skinner, L. B.; Mundy, C. J.; Huthwelker, T.; Schenter, G. K.; Benmore, C. J.; Govind, N.; Fulton, J. L.

    2017-02-01

    A combination of theory, X-ray diffraction (XRD) and extended x-ray absorption fine structure (EXAFS) are used to probe the hydration structure of aqueous Na+. The high spatial resolution of the XRD measurements corresponds to Qmax = 24 Å-1 while the first-reported Na K-edge EXAFS measurements have a spatial resolution corresponding to 2k = Qmax = 16 Å-1. Both provide an accurate measure of the shape and position of the first peak in the Na-O pair distribution function, gNaO(r). The measured Na-O distances of 2.384 ± 0.003 Å (XRD) and 2.37 ± 0.024 Å (EXAFS) are in excellent agreement. These measurements show a much shorter Na-O distance than generally reported in the experimental literature (Na-Oavg ˜ 2.44 Å) although the current measurements are in agreement with recent neutron diffraction measurements. The measured Na-O coordination number from XRD is 5.5 ± 0.3. The measured structure is compared with both classical and first-principles density functional theory (DFT) simulations. Both of the DFT-based methods, revPBE and BLYP, predict a Na-O distance that is too long by about 0.05 Å with respect to the experimental data (EXAFS and XRD). The inclusion of dispersion interactions (-D3 and -D2) significantly worsens the agreement with experiment by further increasing the Na-O distance by 0.07 Å. In contrast, the use of a classical Na-O Lennard-Jones potential with SPC/E water accurately predicts the Na-O distance as 2.39 Å although the Na-O peak is over-structured with respect to experiment.

  8. Revisiting the hydration structure of aqueous Na().

    PubMed

    Galib, M; Baer, M D; Skinner, L B; Mundy, C J; Huthwelker, T; Schenter, G K; Benmore, C J; Govind, N; Fulton, J L

    2017-02-28

    A combination of theory, X-ray diffraction (XRD) and extended x-ray absorption fine structure (EXAFS) are used to probe the hydration structure of aqueous Na(+). The high spatial resolution of the XRD measurements corresponds to Qmax = 24 Å(-1) while the first-reported Na K-edge EXAFS measurements have a spatial resolution corresponding to 2k = Qmax = 16 Å(-1). Both provide an accurate measure of the shape and position of the first peak in the Na-O pair distribution function, gNaO(r). The measured Na-O distances of 2.384 ± 0.003 Å (XRD) and 2.37 ± 0.024 Å (EXAFS) are in excellent agreement. These measurements show a much shorter Na-O distance than generally reported in the experimental literature (Na-Oavg ∼ 2.44 Å) although the current measurements are in agreement with recent neutron diffraction measurements. The measured Na-O coordination number from XRD is 5.5 ± 0.3. The measured structure is compared with both classical and first-principles density functional theory (DFT) simulations. Both of the DFT-based methods, revPBE and BLYP, predict a Na-O distance that is too long by about 0.05 Å with respect to the experimental data (EXAFS and XRD). The inclusion of dispersion interactions (-D3 and -D2) significantly worsens the agreement with experiment by further increasing the Na-O distance by 0.07 Å. In contrast, the use of a classical Na-O Lennard-Jones potential with SPC/E water accurately predicts the Na-O distance as 2.39 Å although the Na-O peak is over-structured with respect to experiment.

  9. Extracellular Na+ inhibits Na+/H+ exchange: cell shrinkage reduces the inhibition.

    PubMed

    Dunham, Philip B; Kelley, Scott J; Logue, Paul J

    2004-08-01

    Na+/H+ exchangers (NHE) are ubiquitous transporters participating in regulation of cell volume and pH. Cell shrinkage, acidification, and growth factors activate NHE by increasing its sensitivity to intracellular H+ concentration. In this study, the kinetics were studied in dog red blood cells of Na+ influx through NHE as a function of external Na+ concentration ([Na+](o)). In cells in isotonic media, [Na+](o) inhibited Na+ influx >40 mM. Osmotic shrinkage activated NHE by reducing this inhibition. In cells in isotonic media + 120 mM sucrose, there was no inhibition, and influx was a hyperbolic function of [Na+](o). The kinetics of Na+-inhibited Na+ influx were analyzed at various extents of osmotic shrinkage. The curves for inhibited Na+ fluxes were sigmoid, indicating more than one Na+ inhibitory site associated with each transporter. Shrinkage significantly increased the Na+ concentration at half-maximal velocity of Na+-inhibited Na+ influx, the mechanism by which shrinkage activates NHE.

  10. Mechanism of epithelial lithium transport. Evidence for basolateral Na:Na and Na:Li exchange

    PubMed Central

    1983-01-01

    Measurement of transmural sodium fluxes across isolated, ouabain- inhibited turtle colon in the presence of a serosal-to-mucosal sodium gradient shows that in the absence of active transport the amiloride- sensitive cellular path contains at least two routes for the transmural movement of sodium and lithium, one a conductive path and the other a nonconductive, cation-exchange mechanism. The latter transport element can exchange lithium for sodium, and the countertransport of these two cations provides a mechanistic basis for the ability of tight epithelia to actively absorb lithium despite the low affinity of the basolateral Na/K-ATPase for this cation. PMID:6644269

  11. Growth of binary organic NLO crystals: m.NA-p.NA and m.NA-CNA system

    NASA Technical Reports Server (NTRS)

    Singh, N. B.; Henningsen, T.; Hopkins, R. H.; Mazelsky, R.

    1993-01-01

    Experiments were carried out to grow 3.Nitroaniline (m.NA) crystals doped with 4.Nitroaniline (p.NA) and 2.chloro 4.Nitroaniline (CNA). The measured undercooling for m.NA, p.NA, and CNA were 0.21 tm K, 0.23 tm K, and 0.35 tm K respectively, where tm represents the melting temperature of the pure component. Because of the crystals' large heat of fusion and large undercooling, it was not possible to grow good quality crystals with low thermal gradients. In the conventional two-zone Bridgman furnace we had to raise the temperature of the hot zone above the decomposition temperature of CNA, p.NA, and m.NA to achieve the desired thermal gradient. To avoid decomposition, we used an unconventional Bridgman furnace. Two immiscible liquids, silicone oil and ethylene glycol, were used to build a special two-zone Bridgman furnace. A temperature gradient of 18 K/cm was achieved without exceeding the decomposition temperature of the crystal. The binary crystals, m.NA-p.NA and m.NA-CNA, were grown in centimeter size in this furnace. X-ray and optical characterization showed good optical quality.

  12. 13C and 23Na NMR studies of Na2C60 and Na6C60 fullerides

    NASA Astrophysics Data System (ADS)

    Rachdi, F.; Hajji, L.; Galtier, M.; Yildirim, T.; Fischer, J. E.; Goze, C.; Mehring, M.

    1997-10-01

    We report on 13C and 23Na NMR measurements on Na2C60 and Na6C60 compounds. The room-temperature 13C NMR spectra of Na2C60 and Na6C60 samples present a narrow isotropic line at 172 and 176 ppm, respectively. The Na6C60 resonance is shifted 20 ppm more down field than the resonances of A6C60 compounds with heavier alkalis, indicating a partial charge transfer to the threefold degenerate t1u level which is totally filled in the latter compounds. The 23Na NMR spectrum of A2C60 shows one line at 73 ppm and the one of A6C60 presents two lines at 73 and 147 ppm. The intensity ratio of the latter lines is about 2:1. According to previously reported x-ray data we attribute the line at 147 ppm to the Na tetramers in the octahedral sites and the line at 73 ppm to the Na cations in the tetrahedral ones which are singly occupied.

  13. Osmoregulation in water-deprived rats drinking hypertonic saline: effect of area postrema lesions.

    PubMed

    Stricker, E M; Craver, C F; Curtis, K S; Peacock-Kinzig, K A; Sved, A F; Smith, J C

    2001-03-01

    Rats drank rapidly when 0.3 M NaCl was the only drinking fluid available after overnight water deprivation, consuming approximately 200 ml/24 h. Although such large intakes of this hypertonic solution initially elevated plasma osmolality, excretion of comparable volumes of urine more concentrated than 300 meq Na(+)/l ultimately appears to restore plasma osmolality to normal levels. Rats drank approximately 100 ml of 0.5 M NaCl after overnight water deprivation, but urine Na(+) concentration (U(Na)) did not increase sufficiently to achieve osmoregulation. When an injected salt load exacerbated the initial dehydration caused by water deprivation, rats increased U(Na) to void the injected load and did not significantly alter 24-h intake of 0.3 or 0.5 M NaCl. Rats with lesions of area postrema had much higher saline intakes and lower U(Na) than did intact control rats; nonetheless, they appeared to osmoregulate well while drinking 0.3 M NaCl but not while drinking 0.5 M NaCl. Detailed analyses of drinking behavior by intact rats suggest that individual bouts were terminated by some rapid postabsorptive consequence of the ingested NaCl load that inhibited further NaCl intake, not by a fixed intake volume or number of licks that temporarily satiated thirst.

  14. Skin Tattoos Alter Sweat Rate and Na+ Concentration.

    PubMed

    Luetkemeier, Maurie Joe; Hanisko, Joseph Michael; Aho, Kyle Mathiew

    2017-07-01

    The popularity of tattoos has increased tremendously in the last 10 yr particularly among athletes and military personnel. The tattooing process involves permanently depositing ink under the skin at a similar depth as eccrine sweat glands (3-5 mm). The purpose of this study was to compare the sweat rate and sweat Na concentration of tattooed versus nontattooed skin. The participants were 10 healthy men (age = 21 ± 1 yr), all with a unilateral tattoo covering a circular area at least 5.2 cm. Sweat was stimulated by iontophoresis using agar gel disks impregnated with 0.5% pilocarpine nitrate. The nontattooed skin was located contralateral to the position of the tattooed skin. The disks used to collect sweat were composed of Tygon® tubing wound into a spiral so that the sweat was pulled into the tubing by capillary action. The sweat rate was determined by weighing the disk before and after sweat collection. The sweat Na concentration was determined by flame photometry. The mean sweat rate from tattooed skin was significantly less than nontattooed skin (0.18 ± 0.15 vs 0.35 ± 0.25 mg·cm·min; P = 0.001). All 10 participants generated less sweat from tattooed skin than nontattooed skin and the effect size was -0.79. The mean sweat Na concentration from tattooed skin was significantly higher than nontattooed skin (69.1 ± 28.9 vs 42.6 ± 15.2 mmol·L; P = 0.02). Nine of 10 participants had higher sweat Na concentration from tattooed skin than nontattooed skin, and the effect size was 1.01. Tattooed skin generated less sweat and a higher Na concentration than nontattooed skin when stimulated by pilocarpine iontophoresis.

  15. Performance comparison of MoNA and LISA neutron detectors

    NASA Astrophysics Data System (ADS)

    Purtell, Kimberly; Rethman, Kaitlynne; Haagsma, Autumn; Finck, Joseph; Smith, Jenna; Snyder, Jesse

    2010-11-01

    In 2002 eight primarily undergraduate institutions constructed and tested the Modular Neutron Array (MoNA) which has been used to detect high energy neutrons at the National Superconducting Cyclotron Laboratory (NSCL). Nine institutions have now designed, constructed and tested the Large-area multi-Institutional Scintillator Array (LISA) neutron detector which will be used at the NSCL and the future Facility for Rare Isotope Beams (FRIB). Both detectors are comprised of 144 detector modules. Each module is a 200 x 10 x 10 cm^3 bar organic plastic scintillator with a photomultiplier tube mounted on each end. Using cosmic rays and a gamma source, we compared the performance of MoNA and LISA by using the same electronics to check light attenuation, position resolution, rise times, and cosmic ray peak widths. Results will be presented.

  16. Maintaining the Na atmosphere of Mercury

    NASA Technical Reports Server (NTRS)

    Killen, Rosemary M.; Morgan, Thomas H.

    1993-01-01

    The possible sources of the Na atmosphere of Mercury are calculatively studied. The likely structure, composition, and temperature of the planet's upper crust is examined along with the probable flux of Na from depth by grain boundary diffusion and by Knudsen flow. The creation of fresh regolith is considered along with mechanisms for supplying Na from the surface to the exosphere. The implications of the calculations for the probable abundances in the regolith are discussed.

  17. Maintaining the NA atmosphere of Mercury

    NASA Astrophysics Data System (ADS)

    Killen, R. M.; Morgan, T. H.

    1993-02-01

    The possible sources of the Na atmosphere of Mercury are calculatively studied. The likely structure, composition, and temperature of the planet's upper crust is examined along with the probable flux of Na from depth by grain boundary diffusion and by Knudsen flow. The creation of fresh regolith is considered along with mechanisms for supplying Na from the surface to the exosphere. The implications of the calculations for the probable abundances in the regolith are discussed.

  18. Na role during sulfurization of NaF/Cu/SnS2 stacked precursor for formation of Cu2SnS3 thin film as absorber of solar cell

    NASA Astrophysics Data System (ADS)

    Suzuki, Koichi; Chantana, Jakapan; Minemoto, Takashi

    2017-08-01

    Cu2SnS3 (CTS) is one of the intriguing absorbers owing to the earth-abandant and nontoxic element. Reaction paths for formations of CTS films through sulfurization of NaF/Cu/SnS2 (with NaF) and Cu/SnS2 (without NaF) stacked precursors are examined. It is revealed that Cu2SnS3 in the resulting film with NaF starts to be formed at the substrate temperature from 400 °C, while Cu2SnS3 in the film without NaF begins to be formed at the substrate temperature over 500 °C. The crystalline grains of resulting CTS films are markedly enlarged by Na addition, where Na is accumulated in the large grain area. The Na has a significant impact on the formation of CTS crystalline grains at lower substrate temperature, thus inducing the enlargement of the crystalline grains. In addition, the monoclinic CTS structure in the absorbers of the CTS solar cells can be formed at the lower temperature with the help of NaF. In addition, Cu2Sn3S7 phase and/or NaxCuSnS3 (x = 0.5-1.0) are only observed in CTS films with NaF.

  19. [SENTIERI-ReNaM: Results].

    PubMed

    Binazzi, Alessandra; Zona, Amerigo; Marinaccio, Alessandro; Bruno, Caterina; Corfiati, Marisa; Fazzo, Lucia; Menegozzo, Simona; Nicita, Carmela; Pasetto, Roberto; Pirastu, Roberta; De Santisi, Marco; Comba, Pietro

    2016-01-01

    Mesothelioma incidence has been analyzed in National Priority Contaminated Sites (NPCSs) to estimate the health impact of asbestos exposure on resident people. The burden of professional and environmental exposures has been identified through data of the Regional Operational Centres (CORs), made available by the Italian National Mesothelioma Registry (ReNaM). An excess of mesothelioma incidence is confirmed in sites with a known past history of direct use of asbestos, such as Balangero, Casale Monferrato, Broni, Bari-Fibronit, and in coastal areas, where shipyards, harbours and other industries that involved a wide use of asbestos are represented (e.g., Trieste, La Spezia, Venice, and Leghorn). An excess of mesothelioma has been observed in settings where the asbestos is not mentioned as contaminant in the decree that included these sites among NPCSs, such as Cengio and Saliceto in Northern Italy; Falconara Marittima and the Bacino Idrografico Fiume Sacco in the Central Italy; the Litorale Domizio Flegreo and Agro Aversano, Milazzo, and Gela in the Southern Italy. Observed excess in the various NPCSs confirms the large-scale occurrence in contaminated Italian sites of a significant amount of total mesothelioma cases observed at national level. The analysis of occupational risk in epidemiological studies with an ecological design helps in defining the contribution of different factors to the overall risk.

  20. Simulation study of Na-majorite

    NASA Astrophysics Data System (ADS)

    Dymshits, A.; Vinograd, V.; Paulsen, N.; Winkler, B.; Perchuk, L.; Bobrov, A.

    2009-04-01

    Garnets, which are found as inclusions in diamonds, often have the excess of Na2O and SiO2 [Stachel, 2001]. Experimental studies suggest that Na is incorporated in pyrope-rich garnet via the coupled substitution Mg+Al=Na+Si [Bobrov et al., 2008]. This study is concerned with the determination of the structure and the thermodynamic properties of NaGrt (Na2MgSi5O12), which is assumed to be the end-member of pyrope-rich garnets with the excess of Na2O and SiO2. Static lattice energy calculations were performed with the program GULP [Gale & Rohl, 2003] using the force-field model [Vinograd et al., 2007] for 200 structures of Na2MgSi5O12 composition. These structures were prepared from Ia3-d pyrope Mg3Al2Si3O12 by replacing all octahedral Al atoms with Si and 2/3 of Mg atoms with Na. The distribution of Mg and Na was varied randomly. The static energies of these structures were cluster expanded using 8 pairwise effective cluster interactions (ECI). The ECIs were used to constrain Monte Carlo simulations within a 4×4×4 supercell (NNN exchangeable sites). The annealing experiments have shown that the lowest energy structure has the space group I4

  1. Painful Na-channelopathies: an expanding universe.

    PubMed

    Waxman, Stephen G

    2013-07-01

    The universe of painful Na-channelopathies--human disorders caused by mutations in voltage-gated sodium channels--has recently expanded in three dimensions. We now know that mutations of sodium channels cause not only rare genetic 'model disorders' such as inherited erythromelalgia and channelopathy-associated insensitivity to pain but also common painful neuropathies. We have learned that mutations of NaV1.8, as well as mutations of NaV1.7, can cause painful Na-channelopathies. Moreover, recent studies combining atomic level structural models and pharmacogenomics suggest that the goal of genomically guided pain therapy may not be unrealistic.

  2. NA-NET numerical analysis net

    SciTech Connect

    Dongarra, J. . Dept. of Computer Science Oak Ridge National Lab., TN ); Rosener, B. . Dept. of Computer Science)

    1991-12-01

    This report describes a facility called NA-NET created to allow numerical analysts (na) an easy method of communicating with one another. The main advantage of the NA-NET is uniformity of addressing. All mail is addressed to the Internet host na-net.ornl.gov'' at Oak Ridge National Laboratory. Hence, members of the NA-NET do not need to remember complicated addresses or even where a member is currently located. As long as moving members change their e-mail address in the NA-NET everything works smoothly. The NA-NET system is currently located at Oak Ridge National Laboratory. It is running on the same machine that serves netlib. Netlib is a separate facility that distributes mathematical software via electronic mail. For more information on netlib consult, or send the one-line message send index'' to netlib{at}ornl.gov. The following report describes the current NA-NET system from both a user's perspective and from an implementation perspective. Currently, there are over 2100 members in the NA-NET. An average of 110 mail messages pass through this facility daily.

  3. NA-NET numerical analysis net

    SciTech Connect

    Dongarra, J. |; Rosener, B.

    1991-12-01

    This report describes a facility called NA-NET created to allow numerical analysts (na) an easy method of communicating with one another. The main advantage of the NA-NET is uniformity of addressing. All mail is addressed to the Internet host ``na-net.ornl.gov`` at Oak Ridge National Laboratory. Hence, members of the NA-NET do not need to remember complicated addresses or even where a member is currently located. As long as moving members change their e-mail address in the NA-NET everything works smoothly. The NA-NET system is currently located at Oak Ridge National Laboratory. It is running on the same machine that serves netlib. Netlib is a separate facility that distributes mathematical software via electronic mail. For more information on netlib consult, or send the one-line message ``send index`` to netlib{at}ornl.gov. The following report describes the current NA-NET system from both a user`s perspective and from an implementation perspective. Currently, there are over 2100 members in the NA-NET. An average of 110 mail messages pass through this facility daily.

  4. NaTaO3 photocatalysts of different crystalline structures for water splitting into H2 and O2

    NASA Astrophysics Data System (ADS)

    Lin, Wan-Hsien; Cheng, Ching; Hu, Che-Chia; Teng, Hsisheng

    2006-11-01

    Perovskite-type NaTaO3 derived from a sol-gel synthesis exhibited a larger surface area and a remarkably higher photocatalytic activity in water splitting than the solid-state synthesized NaTaO3. The sol-gel and solid-state NaTaO3 had different crystalline structures of monoclinic P2/m and orthorhombic Pcmn, respectively. Diffuse reflectance spectra showed that the sol-gel specimen had a slightly larger band gap. The band structure analysis revealed an indirect band gap for the sol-gel NaTaO3, contrary to the direct band gap of the solid-state one. The difference in the electronic structure and surface area explained the higher photocatalytic activity of the sol-gel NaTaO3.

  5. Area contingency plan Wisconsin area. (COTP Milwaukee)

    SciTech Connect

    1994-06-30

    The Area Contingency Plan, mandated under the Oil Pollution Act, was developed by the Eastern Wisconsin Area Committee, which is chaired by the Coast Guard and consists of local, state, federal, and private members. The plan prepares in advance for an oil or hazardous substance spill in the COTP Milwaukee Coastal Zone.

  6. Area contingency plan Chicago area. (COTP Chicago)

    SciTech Connect

    1995-06-01

    The Area Contingency Plan, mandated under the Oil Pollution Act, was developed by the Chicago Area Committee, which is chaired by the Coast Guard and consists of local, state, federal, and private members. The plan prepares in advance for an oil or hazardous substance spill in the COTP Chicago Coastal Zone.

  7. Health Service Areas (HSAs) - Small Area Estimates

    Cancer.gov

    Health Service Areas (HSAs) are a compromise between the 3000 counties and the 50 states. An HSA may be thought of as an area that is relatively self-contained with respect to hospital care and may cross over state boundries.

  8. First mesopause Na retrievals from satellite Na D-line nightglow observations

    NASA Astrophysics Data System (ADS)

    Savigny, C.; Langowski, M. P.; Zilker, B.; Burrows, J. P.; Fussen, D.; Sofieva, V. F.

    2016-12-01

    We report the retrieval of Na concentration profiles in the mesopause region from satellite observations of the Na D-line nightglow emission near 589 nm made by the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) on the Envisat spacecraft. The retrieval assumes the Na D-line excitation mechanism originally proposed by Chapman in 1939. The retrieval approach, including treatment of self-absorption by Na, a retrieval uncertainty budget, and first retrieval results, is presented. The retrieved Na profiles are compared to independent satellite measurements. Good agreement in terms of peak altitude, peak concentration, and vertical column density is found. The retrievals constitute the first Na profile retrievals from satellite observations of the Na D-line nightglow emission profile. They enable our understanding of the Na nightglow excitation mechanism to be tested.

  9. Na+/Ca2+ exchange and Na+/K+-ATPase in the heart

    PubMed Central

    Shattock, Michael J; Ottolia, Michela; Bers, Donald M; Blaustein, Mordecai P; Boguslavskyi, Andrii; Bossuyt, Julie; Bridge, John H B; Chen-Izu, Ye; Clancy, Colleen E; Edwards, Andrew; Goldhaber, Joshua; Kaplan, Jack; Lingrel, Jerry B; Pavlovic, Davor; Philipson, Kenneth; Sipido, Karin R; Xie, Zi-Jian

    2015-01-01

    This paper is the third in a series of reviews published in this issue resulting from the University of California Davis Cardiovascular Symposium 2014: Systems approach to understanding cardiac excitation–contraction coupling and arrhythmias: Na+ channel and Na+ transport. The goal of the symposium was to bring together experts in the field to discuss points of consensus and controversy on the topic of sodium in the heart. The present review focuses on cardiac Na+/Ca2+ exchange (NCX) and Na+/K+-ATPase (NKA). While the relevance of Ca2+ homeostasis in cardiac function has been extensively investigated, the role of Na+ regulation in shaping heart function is often overlooked. Small changes in the cytoplasmic Na+ content have multiple effects on the heart by influencing intracellular Ca2+ and pH levels thereby modulating heart contractility. Therefore it is essential for heart cells to maintain Na+ homeostasis. Among the proteins that accomplish this task are the Na+/Ca2+ exchanger (NCX) and the Na+/K+ pump (NKA). By transporting three Na+ ions into the cytoplasm in exchange for one Ca2+ moved out, NCX is one of the main Na+ influx mechanisms in cardiomyocytes. Acting in the opposite direction, NKA moves Na+ ions from the cytoplasm to the extracellular space against their gradient by utilizing the energy released from ATP hydrolysis. A fine balance between these two processes controls the net amount of intracellular Na+ and aberrations in either of these two systems can have a large impact on cardiac contractility. Due to the relevant role of these two proteins in Na+ homeostasis, the emphasis of this review is on recent developments regarding the cardiac Na+/Ca2+ exchanger (NCX1) and Na+/K+ pump and the controversies that still persist in the field. PMID:25772291

  10. Exploration of NaVOPO4 as a cathode for a Na-ion battery.

    PubMed

    Song, Jie; Xu, Maowen; Wang, Long; Goodenough, John B

    2013-06-11

    Monoclinic NaVOPO4 is explored as a cathode material for a sodium ion battery. It exhibits electrochemical activity operating at an average potential of 3.6 V (vs. Na(+)/Na) and delivers a reversible capacity of 90 mA h g(-1) at 1/15 C.

  11. Kinetin Reversal of NaCl Effects

    PubMed Central

    Katz, Adriana; Dehan, Klara; Itai, Chanan

    1978-01-01

    Leaf discs of Nicotiana rustica L. were floated on NaCl in the presence of kinetin or abscisic acid. On the 5th day 14CO2 fixation, [3H]leucine incorporation, stomatal conductance, and chlorophyll content were determined. Kinetin either partially or completely reversed the inhibitory effects of NaCl while ABA had no effect. PMID:16660618

  12. RATTLESNAKE ROADLESS AREA, MONTANA.

    USGS Publications Warehouse

    Wallace, C.A.; Mayerle, Ronald T.

    1984-01-01

    Geologic, geochemical, and geophysical surveys of the Rattlesnake Roadless Area in Montana identified a small area of substantiated resource potential for a low-grade stratabound copper occurrence along the northwest border of the area. A demonstrated barite (BaSO//4) resource of 45 tons and a demonstrated limestone resource suitable for cement production are present in the southern part of the roadless area. Limestone, silica in quartz veins, and sand and gravel deposits are known in the southern part of the area but similar deposits occur widely outside the study area. There is little promise for the occurrence of energy resources in the Rattlesnake Roadless Area.

  13. Selective catalytic reduction of NO{sub 2} with urea in nanocrystalline NaY zeolite

    SciTech Connect

    Gonghu Li; Conrad A. Jones; Vicki H. Grassian; Sarah C. Larsen

    2005-09-10

    In this study, the selective catalytic reduction (SCR) of NO{sub 2} with urea in nanocrystalline NaY zeolite was investigated with in situ transmission Fourier transform infrared (FTIR) spectroscopy and solid-state nuclear magnetic resonance spectroscopy. At T=473 K, the reaction rate for urea-SCR of NO{sub 2} in nanocrystalline NaY zeolite was significantly greater than that in commercial NaY zeolite with a larger crystal size. In addition, a dramatic decrease in the concentration of undesirable surface species, including biuret and cyanuric acid, was observed in nanocrystalline NaY compared with commercial NaY after urea-SCR of NO{sub 2} at T=473 K. The increased reactivity for urea-SCR of NO{sub 2} was attributed to silanol groups and extra-framework aluminum species located on the external surface of nanocrystalline NaY. Specifically, NOx storage as nitrate and nitrite on the internal zeolite surface was coupled to reactive deNOx sites on the external surface. Isotopic labeling combined with IR analysis suggest that NN bond formation involved both an N-atom originating from NO{sub 2} and an N-atom originating from urea. This is the first clear example demonstrating that the increased external surface area (up to 40% of total surface area) of nanocrystalline zeolites can be used as a reactive surface with unique active sites for catalysis.

  14. Sodium Ion Diffusion in Nasicon (Na3Zr2Si2PO12) Solid Electrolytes: Effects of Excess Sodium.

    PubMed

    Park, Heetaek; Jung, Keeyoung; Nezafati, Marjan; Kim, Chang-Soo; Kang, Byoungwoo

    2016-10-04

    The Na superionic conductor (aka Nasicon, Na1+xZr2SixP3-xO12, where 0 ≤ x ≤ 3) is one of the promising solid electrolyte materials used in advanced molten Na-based secondary batteries that typically operate at high temperature (over ∼270 °C). Nasicon provides a 3D diffusion network allowing the transport of the active Na-ion species (i.e., ionic conductor) while blocking the conduction of electrons (i.e., electronic insulator) between the anode and cathode compartments of cells. In this work, the standard Nasicon (Na3Zr2Si2PO12, bare sample) and 10 at% Na-excess Nasicon (Na3.3Zr2Si2PO12, Na-excess sample) solid electrolytes were synthesized using a solid-state sintering technique to elucidate the Na diffusion mechanism (i.e., grain diffusion or grain boundary diffusion) and the impacts of adding excess Na at relatively low and high temperatures. The structural, thermal, and ionic transport characterizations were conducted using various experimental tools including X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). In addition, an ab initio atomistic modeling study was carried out to computationally examine the detailed microstructures of Nasicon materials, as well as to support the experimental observations. Through this combination work comprising experimental and computational investigations, we show that the predominant mechanisms of Na-ion transport in the Nasicon structure are the grain boundary and the grain diffusion at low and high temperatures, respectively. Also, it was found that adding 10 at% excess Na could give rise to a substantial increase in the total conductivity (e.g., ∼1.2 × 10(-1) S/cm at 300 °C) of Nasicon electrolytes resulting from the enlargement of the bottleneck areas in the Na diffusion channels of polycrystalline grains.

  15. High NA Nicrostepper Final Optical Design Report

    SciTech Connect

    Hudyma, R

    1999-09-24

    The development of a new EUV high NA small-field exposure tool has been proposed for obtaining mask defect printability data in a timeframe several years before beta-tools are available. The imaging system for this new Micro-Exposure Tool (MET), would have a numerical aperture (NA) of about 0.3, similar to the NA for a beta-tool, but substantially larger than the 0.10 NA for the Engineering Test Stand (ETS) and 0.088 NA for the existing 10x Microstepper. This memorandum discusses the development and summarizes the performance of the camera for the MET and includes a listing of the design prescription, detailed analysis of the distortion, and analysis demonstrating the capability to resolution 30 nm features under the conditions of partially coherent illumination.

  16. Negative electrodes for Na-ion batteries.

    PubMed

    Dahbi, Mouad; Yabuuchi, Naoaki; Kubota, Kei; Tokiwa, Kazuyasu; Komaba, Shinichi

    2014-08-07

    Research interest in Na-ion batteries has increased rapidly because of the environmental friendliness of sodium compared to lithium. Throughout this Perspective paper, we report and review recent scientific advances in the field of negative electrode materials used for Na-ion batteries. This paper sheds light on negative electrode materials for Na-ion batteries: carbonaceous materials, oxides/phosphates (as sodium insertion materials), sodium alloy/compounds and so on. These electrode materials have different reaction mechanisms for electrochemical sodiation/desodiation processes. Moreover, not only sodiation-active materials but also binders, current collectors, electrolytes and electrode/electrolyte interphase and its stabilization are essential for long cycle life Na-ion batteries. This paper also addresses the prospect of Na-ion batteries as low-cost and long-life batteries with relatively high-energy density as their potential competitive edge over the commercialized Li-ion batteries.

  17. Inactivation of tannins in milled sorghum grain through steeping in dilute NaOH solution.

    PubMed

    Adetunji, Adeoluwa I; Duodu, Kwaku G; Taylor, John R N

    2015-05-15

    Steeping milled sorghum in up to 0.4% NaOH was investigated as a method of tannin inactivation. NaOH steeping substantially reduced assayable total phenols and tannins in both Type III and Type II sorghums and with Type III sorghum caused a 60-80% reduction in α-amylase inhibition compared to a 20% reduction by water steeping. NaOH treatment also reduced starch liquefaction time and increased free amino nitrogen. Type II tannin sorghum did not inhibit α-amylase and consequently the NaOH treatment had no effect. HPLC and LC-MS of the tannin extracts indicated a general trend of increasing proanthocyanidin/procyanidin size with increasing NaOH concentration and steeping time, coupled with a reduction in total area of peaks resolved. These show that the NaOH treatment forms highly polymerised tannin compounds, too large to assay and to interact with the α-amylase. NaOH pre-treatment of Type III sorghums could enable their utilisation in bioethanol production.

  18. NA61/SHINE facility at the CERN SPS: beams and detector system

    NASA Astrophysics Data System (ADS)

    Abgrall, N.; Andreeva, O.; Aduszkiewicz, A.; Ali, Y.; Anticic, T.; Antoniou, N.; Baatar, B.; Bay, F.; Blondel, A.; Blumer, J.; Bogomilov, M.; Bogusz, M.; Bravar, A.; Brzychczyk, J.; Bunyatov, S. A.; Christakoglou, P.; Cirkovic, M.; Czopowicz, T.; Davis, N.; Debieux, S.; Dembinski, H.; Diakonos, F.; Di Luise, S.; Dominik, W.; Drozhzhova, T.; Dumarchez, J.; Dynowski, K.; Engel, R.; Efthymiopoulos, I.; Ereditato, A.; Fabich, A.; Feofilov, G. A.; Fodor, Z.; Fulop, A.; Gaździcki, M.; Golubeva, M.; Grebieszkow, K.; Grzeszczuk, A.; Guber, F.; Haesler, A.; Hasegawa, T.; Hierholzer, M.; Idczak, R.; Igolkin, S.; Ivashkin, A.; Jokovic, D.; Kadija, K.; Kapoyannis, A.; Kaptur, E.; Kielczewska, D.; Kirejczyk, M.; Kisiel, J.; Kiss, T.; Kleinfelder, S.; Kobayashi, T.; Kolesnikov, V. I.; Kolev, D.; Kondratiev, V. P.; Korzenev, A.; Koversarski, P.; Kowalski, S.; Krasnoperov, A.; Kurepin, A.; Larsen, D.; Laszlo, A.; Lyubushkin, V. V.; Maćkowiak-Pawłowska, M.; Majka, Z.; Maksiak, B.; Malakhov, A. I.; Maletic, D.; Manglunki, D.; Manic, D.; Marchionni, A.; Marcinek, A.; Marin, V.; Marton, K.; Mathes, H.-J.; Matulewicz, T.; Matveev, V.; Melkumov, G. L.; Messina, M.; Mrówczyński, St.; Murphy, S.; Nakadaira, T.; Nirkko, M.; Nishikawa, K.; Palczewski, T.; Palla, G.; Panagiotou, A. D.; Paul, T.; Peryt, W.; Petukhov, O.; Pistillo, C.; Płaneta, R.; Pluta, J.; Popov, B. A.; Posiadala, M.; Puławski, S.; Puzovic, J.; Rauch, W.; Ravonel, M.; Redij, A.; Renfordt, R.; Richter-Was, E.; Robert, A.; Röhrich, D.; Rondio, E.; Rossi, B.; Roth, M.; Rubbia, A.; Rustamov, A.; Rybczyński, M.; Sadovsky, A.; Sakashita, K.; Savic, M.; Schmidt, K.; Sekiguchi, T.; Seyboth, P.; Sgalaberna, D.; Shibata, M.; Sipos, R.; Skrzypczak, E.; Słodkowski, M.; Sosin, Z.; Staszel, P.; Stefanek, G.; Stepaniak, J.; Stroebele, H.; Susa, T.; Szuba, M.; Tada, M.; Tereshchenko, V.; Tolyhi, T.; Tsenov, R.; Turko, L.; Ulrich, R.; Unger, M.; Vassiliou, M.; Veberic, D.; Vechernin, V. V.; Vesztergombi, G.; Vinogradov, L.; Wilczek, A.; Włodarczyk, Z.; Wojtaszek-Szwarz, A.; Wyszyński, O.; Zambelli, L.; Zipper, W.

    2014-06-01

    NA61/SHINE (SPS Heavy Ion and Neutrino Experiment) is a multi-purpose experimental facility to study hadron production in hadron-proton, hadron-nucleus and nucleus-nucleus collisions at the CERN Super Proton Synchrotron. It recorded the first physics data with hadron beams in 2009 and with ion beams (secondary 7Be beams) in 2011. NA61/SHINE has greatly profited from the long development of the CERN proton and ion sources and the accelerator chain as well as the H2 beamline of the CERN North Area. The latter has recently been modified to also serve as a fragment separator as needed to produce the Be beams for NA61/SHINE. Numerous components of the NA61/SHINE set-up were inherited from its predecessors, in particular, the last one, the NA49 experiment. Important new detectors and upgrades of the legacy equipment were introduced by the NA61/SHINE Collaboration. This paper describes the state of the NA61/SHINE facility — the beams and the detector system — before the CERN Long Shutdown I, which started in March 2013.

  19. Na+ binding to the Na(+)-glucose cotransporter is potential dependent.

    PubMed

    Bennett, E; Kimmich, G A

    1992-02-01

    Activity of the Na(+)-glucose cotransporter in LLC-PK1 epithelial cells was assayed by measuring sugar-induced currents (IAMG) using whole cell recording techniques. IAMG was compared among cells by standardizing the measured currents to cell size using cell capacitance measurements. IAMG at a given membrane potential was measured as a function of alpha-methylglucoside (AMG) concentration and can be fit to Michaelis-Menten kinetics. IAMG at varying Na+ concentrations can be described by the Hill equation with a Hill coefficient of 1.6 at all tested potentials. At high external Na+ levels (155 mM), Na+ is at least 90% saturating at all tested potentials. Maximal currents at a given membrane potential (Im) are calculated from the Michaelis-Menten equation fit to data measuring IAMG vs. AMG concentration at a constant Na+ concentration. Im showed potential dependence under all conditions. Potential-dependent Na+ binding rate(s) cannot alone explain the observed potential dependence of Im under saturating Na+ conditions. Therefore, because Im is potential dependent, at least one step of the transport cycle other than external Na+ binding must be potential dependent. Im was also calculated from data taken at 40 mM external Na+. At all potentials studied, Im at 155 mM Na+ is greater than Im calculated at 40 mM Na+. This implies that the rate of external Na+ binding to the transporter at 40 mM also affects the maximal transport rate. Furthermore, Im at 40 mM external Na+ increases with hyperpolarization faster than Im at 155 mM Na+. Together, these facts indicate that the rate at which Na+ binds to the transporter is also potential dependent.(ABSTRACT TRUNCATED AT 250 WORDS)

  20. Na-doped optical Germanium bulk crystals

    NASA Astrophysics Data System (ADS)

    Pekar, G. S.; Singaevsky, A. F.

    2012-09-01

    In an effort to develop a material for infrared (IR) optics with improved parameters, bulk crystals of optical germanium doped with Na have been first grown and studied. Single-crystalline and coarse-crystalline Ge:Na boules of different shapes and dimensions, up to 10 kg by weight, have been grown. Sodium was incorporated into the Ge crystal during the crystal growing from the melt. Despite the fact that Na contamination in the source material was not strictly controlled, the density of Na in the grown crystals determined by the neutron activation analysis as well as by the glow discharge mass spectrometry did not exceed 1015 cm-3. Just this value may be supposed to be close to the solubility limit of Na incorporated in Ge in the course of bulk crystal growth. A first demonstration of donor behavior of Na in bulk Ge crystals is made by means of a thermoelectric type of testing. An interstitial location of Na impurity has been verified by experiments on donor drift in the dc electric field. The crystals are grown with free electron density in the range from 5ṡ1013 to 4ṡ1014 cm-3 which is optimal for using Ge crystals as an optical material for fabricating passive elements of the IR technique. A comparison between the properties of Ge:Na crystals and Ge crystals doped with Sb, a conventional impurity in optical germanium, grown under the same technological conditions and from the same intrinsic Ge as a source material, revealed a number of advantages of Ge:Na crystals; among them, the higher transparency in the IR region, smaller radiation scattering and higher regular optical transmission, lower dislocation density, more uniform distribution of electrical and optical characteristics over the crystal volume, the identity of optical parameters in the single-crystalline, and coarse-crystalline boules. No degradation of optical elements fabricated from Ge:Na crystals was detected in the course of their commercial application, starting from 1998.

  1. Pharmacological modulation of human cardiac Na+ channels.

    PubMed

    Krafte, D S; Davison, K; Dugrenier, N; Estep, K; Josef, K; Barchi, R L; Kallen, R G; Silver, P J; Ezrin, A M

    1994-02-15

    Pharmacological modulation of human sodium current was examined in Xenopus oocytes expressing human heart Na+ channels. Na+ currents activated near -50 mV with maximum current amplitudes observed at -20 mV. Steady-state inactivation was characterized by a V1/2 value of -57 +/- 0.5 mV and a slope factor (k) of 7.3 +/- 0.3 mV. Sodium currents were blocked by tetrodotoxin with an IC50 value of 1.8 microM. These properties are consistent with those of Na+ channels expressed in mammalian myocardial cells. We have investigated the effects of several pharmacological agents which, with the exception of lidocaine, have not been characterized against cRNA-derived Na+ channels expressed in Xenopus oocytes. Lidocaine, quinidine and flecainide blocked resting Na+ channels with IC50 values of 521 microM, 198 microM, and 41 microM, respectively. Use-dependent block was also observed for all three agents, but concentrations necessary to induce block were higher than expected for quinidine and flecainide. This may reflect differences arising due to expression in the Xenopus oocyte system or could be a true difference in the interaction between human cardiac Na+ channels and these drugs compared to other mammalian Na+ channels. Importantly, however, this result would not have been predicted based upon previous studies of mammalian cardiac Na+ channels. The effects of DPI 201-106, RWJ 24517, and BDF 9148 were also tested and all three agents slowed and/or removed Na+ current inactivation, reduced peak current amplitudes, and induced use-dependent block. These data suggest that the alpha-subunit is the site of interaction between cardiac Na+ channels and Class I antiarrhythmic drugs as well as inactivation modifiers such as DPI 201-106.

  2. Transgenerational soil-mediated differences between plants experienced or naïve to a grass invasion.

    PubMed

    Deck, Anna; Muir, Adrianna; Strauss, Sharon

    2013-10-01

    Invasive species may undergo rapid change as they invade. Native species persisting in invaded areas may also experience rapid change over this short timescale relative to native populations in uninvaded areas. We investigated the response of the native Achillea millefolium to soil from Holcus lanatus-invaded and uninvaded areas, and we sought to determine whether differential responses between A. millefolium from invaded (invader experienced) and uninvaded (invader naïve) areas were mediated by soil community changes. Plants grown from seed from experienced and naïve areas responded differently to invaded and uninvaded soil with respect to germination time, biomass, and height. Overall, experienced plants grew faster and taller than their naïve counterparts. Naïve native plants showed negative feedbacks with their home soil and positive feedbacks with invaded soil; experienced plants were less responsive to soil differences. Our results suggest that native plants naïve to invasion may be more sensitive to soil communities than experienced plants, consistent with recent studies. While differences between naïve and experienced plants are transgenerational, our design cannot differentiate between differences that are genetically based, plastic, or both. Regardless, our results highlight the importance of seed source and population history in restoration, emphasizing the restoration potential of experienced seed sources.

  3. Transgenerational soil-mediated differences between plants experienced or naïve to a grass invasion

    PubMed Central

    Deck, Anna; Muir, Adrianna; Strauss, Sharon

    2013-01-01

    Invasive species may undergo rapid change as they invade. Native species persisting in invaded areas may also experience rapid change over this short timescale relative to native populations in uninvaded areas. We investigated the response of the native Achillea millefolium to soil from Holcus lanatus-invaded and uninvaded areas, and we sought to determine whether differential responses between A. millefolium from invaded (invader experienced) and uninvaded (invader naïve) areas were mediated by soil community changes. Plants grown from seed from experienced and naïve areas responded differently to invaded and uninvaded soil with respect to germination time, biomass, and height. Overall, experienced plants grew faster and taller than their naïve counterparts. Naïve native plants showed negative feedbacks with their home soil and positive feedbacks with invaded soil; experienced plants were less responsive to soil differences. Our results suggest that native plants naïve to invasion may be more sensitive to soil communities than experienced plants, consistent with recent studies. While differences between naïve and experienced plants are transgenerational, our design cannot differentiate between differences that are genetically based, plastic, or both. Regardless, our results highlight the importance of seed source and population history in restoration, emphasizing the restoration potential of experienced seed sources. PMID:24198931

  4. Long range intermolecular interactions between the alkali diatomics Na2, K2, and NaK

    NASA Astrophysics Data System (ADS)

    Zemke, Warren T.; Byrd, Jason N.; Michels, H. Harvey; Montgomery, John A.; Stwalley, William C.

    2010-06-01

    Long range interactions between the ground state alkali diatomics Na2-Na2, K2-K2, Na2-K2, and NaK-NaK are examined. Interaction energies are first determined from ab initio calculations at the coupled-cluster with singles, doubles, and perturbative triples [CCSD(T)] level of theory, including counterpoise corrections. Long range energies calculated from diatomic molecular properties (polarizabilities and dipole and quadrupole moments) are then compared with the ab initio energies. A simple asymptotic model potential ELR=Eelec+Edisp+Eind is shown to accurately represent the intermolecular interactions for these systems at long range.

  5. Long range intermolecular interactions between the alkali diatomics Na(2), K(2), and NaK.

    PubMed

    Zemke, Warren T; Byrd, Jason N; Michels, H Harvey; Montgomery, John A; Stwalley, William C

    2010-06-28

    Long range interactions between the ground state alkali diatomics Na(2)-Na(2), K(2)-K(2), Na(2)-K(2), and NaK-NaK are examined. Interaction energies are first determined from ab initio calculations at the coupled-cluster with singles, doubles, and perturbative triples [CCSD(T)] level of theory, including counterpoise corrections. Long range energies calculated from diatomic molecular properties (polarizabilities and dipole and quadrupole moments) are then compared with the ab initio energies. A simple asymptotic model potential E(LR)=E(elec)+E(disp)+E(ind) is shown to accurately represent the intermolecular interactions for these systems at long range.

  6. MoNA - The Modular Neutron Array at the NSCL

    SciTech Connect

    Baumann, T.; Brown, J.A.; DeYoung, P.; Peaslee, G.F.; Finck, J.E.; Hinnefeld, J.D.; Howes, R.; Kemper, K.W.; Tabor, S.L.; Luther, B.A.; Pancella, P.V.; Rogers, W.F.; Thoennessen, M.

    2003-08-26

    The Modular Neutron Array (MoNA) is a highly efficient large-area neutron detector for the detection of high-energy neutrons to be used in experiments with fast rare isotopes at the National Superconducting Cyclotron Laboratory. The detector is designed for the detection of neutrons between 50 MeV and 250 MeV with an efficiency of up to 70%. This detector was proposed and is being built by a collaboration of ten institutions, including a large number of undergraduate schools.

  7. Kinetic Analysis of Membrane Potential Dye Response to NaV1.7 Channel Activation Identifies Antagonists with Pharmacological Selectivity against NaV1.5.

    PubMed

    Finley, Michael; Cassaday, Jason; Kreamer, Tony; Li, Xinnian; Solly, Kelli; O'Donnell, Greg; Clements, Michelle; Converso, Antonella; Cook, Sean; Daley, Chris; Kraus, Richard; Lai, Ming-Tain; Layton, Mark; Lemaire, Wei; Staas, Donnette; Wang, Jixin

    2016-06-01

    The NaV1.7 voltage-gated sodium channel is a highly valued target for the treatment of neuropathic pain due to its expression in pain-sensing neurons and human genetic mutations in the gene encoding NaV1.7, resulting in either loss-of-function (e.g., congenital analgesia) or gain-of-function (e.g., paroxysmal extreme pain disorder) pain phenotypes. We exploited existing technologies in a novel manner to identify selective antagonists of NaV1.7. A full-deck high-throughput screen was developed for both NaV1.7 and cardiac NaV1.5 channels using a cell-based membrane potential dye FLIPR assay. In assay development, known local anesthetic site inhibitors produced a decrease in maximal response; however, a subset of compounds exhibited a concentration-dependent delay in the onset of the response with little change in the peak of the response at any concentration. Therefore, two methods of analysis were employed for the screen: one to measure peak response and another to measure area under the curve, which would capture the delay-to-onset phenotype. Although a number of compounds were identified by a selective reduction in peak response in NaV1.7 relative to 1.5, the AUC measurement and a subsequent refinement of this measurement were able to differentiate compounds with NaV1.7 pharmacological selectivity over NaV1.5 as confirmed in electrophysiology.

  8. CUCAMONGA ROADLESS AREAS, CALIFORNIA.

    USGS Publications Warehouse

    Morton, Douglas M.; Peters, Thomas J.

    1984-01-01

    On the basis of geologic, geochemical, and geophysical surveys and an investigation of mines, prospects, and mineralized areas, the Cucamonga Roadless Areas in California have two areas of probable mineral-resource potential. An area of probable mineral-resource potential for low-grade tungsten and gold resources is located in the northern part of the roadless areas, and an area of similar potential for small deposits of silver, lead, and zinc is located in the southwestern part of the roadless areas. An interpretation of an aeromagnetic survey of the Cucamonga Roadless Areas showed magnetic anomalies and patterns closely related to magnetic variation in rock units, but indicated no unknown areas of mineral-resource potential.

  9. Cytosolic Na+ controls and epithelial Na+ channel via the Go guanine nucleotide-binding regulatory protein.

    PubMed Central

    Komwatana, P; Dinudom, A; Young, J A; Cook, D I

    1996-01-01

    In tight Na+-absorbing epithelial cells, the fate of Na+ entry through amiloride-sensitive apical membrane Na+ channels is matched to basolateral Na+ extrusion so that cell Na+ concentration and volume remain steady. Control of this process by regulation of apical Na+ channels has been attributed to changes in cytosolic Ca2+ concentration or pH, secondary to changes in cytosolic Na+ concentration, although cytosolic Cl- seems also to be involved. Using mouse mandibular gland duct cells, we now demonstrate that increasing cytosolic Na+ concentration inhibits apical Na+ channels independent of changes in cytosolic Ca2+, pH, or Cl-, and the effect is blocked by GDP-beta-S, pertussis toxin, and antibodies against the alpha-subunits of guanine nucleotide-binding regulatory proteins (Go). In contrast, the inhibitory effect of cytosolic anions is blocked by antibodies to inhibitory guanine nucleotide-binding regulatory proteins (Gi1/Gi2. It thus appears that apical Na+ channels are regulated by Go and Gi proteins, the activities of which are controlled, respectively, by cytosolic Na+ and Cl-. Images Fig. 4 PMID:8755611

  10. Cytosolic Na+ Controls an Epithelial Na+ Channel Via the Go Guanine Nucleotide-Binding Regulatory Protein

    NASA Astrophysics Data System (ADS)

    Komwatana, P.; Dinudom, A.; Young, J. A.; Cook, D. I.

    1996-07-01

    In tight Na+-absorbing epithelial cells, the rate of Na+ entry through amiloride-sensitive apical membrane Na+ channels is matched to basolateral Na+ extrusion so that cell Na+ concentration and volume remain steady. Control of this process by regulation of apical Na+ channels has been attributed to changes in cytosolic Ca2+ concentration or pH, secondary to changes in cytosolic Na+ concentration, although cytosolic Cl- seems also to be involved. Using mouse mandibular gland duct cells, we now demonstrate that increasing cytosolic Na+ concentration inhibits apical Na+ channels independent of changes in cytosolic Ca2+, pH, or Cl-, and the effect is blocked by GDP-β -S, pertussis toxin, and antibodies against the α -subunits of guanine nucleotide-binding regulatory proteins (Go). In contrast, the inhibitory effect of cytosolic anions is blocked by antibodies to inhibitory guanine nucleotide-binding regulatory proteins (Gi1/Gi2. It thus appears that apical Na+ channels are regulated by Go and Gi proteins, the activities of which are controlled, respectively, by cytosolic Na+ and Cl-.

  11. Anomalously high Na(+) and low Li(+) mobility in intercalated Na2Ti6O13.

    PubMed

    Ling, Chen; Zhang, Ruigang

    2017-04-12

    We report an anomalous diffusion behavior in intercalated Na2Ti6O13. Using first-principles calculations, the direct migration of inserted Na(+) along the tunnel direction is predicted to have a barrier of 0.24-0.44 eV, while the migration of inserted Li(+) along the tunnel direction has a barrier of 0.86-1.15 eV. Although Li(+) can also diffuse along a zig-zag path in the tunnel, the barrier of 0.86-0.99 eV is still much higher than that for Na(+). Our results surprisingly lead to the conclusion that the diffusion of larger Na(+) is 4-8 orders of magnitude faster than Li(+) in the same host lattice, and explain the experimentally observed exceptional rate capability of Na2Ti6O13 as the Na-ion battery anode. The anomalous diffusion behavior is attributed to the geometric features of Na2Ti6O13. For migration of Li(+) it is necessary to weaken Li-O bonds and to overcome the repulsion between Li and host Na ions simultaneously, while for Na(+) diffusion the improved Na-O bonding at the transition state partially compensates for the energy penalty from the repulsion of host Na ions.

  12. Benchmarking EUV mask inspection beyond 0.25 NA

    SciTech Connect

    Goldberg, Kenneth A.; Mochi, Iacopo; Anderson, Erik H.; Rekawa, Seno B.; Kemp, Charles D.; Huh, S.; Han, H.-S.; Naulleau, P.; Gunion, R.F.

    2008-09-18

    The SEMATECH Berkeley Actinic Inspection Tool (AIT) is an EUV-wavelength mask inspection microscope designed for direct aerial image measurements, and pre-commercial EUV mask research. Operating on a synchrotron bending magnet beamline, the AIT uses an off-axis Fresnel zoneplate lens to project a high-magnification EUV image directly onto a CCD camera. We present the results of recent system upgrades that have improved the imaging resolution, illumination uniformity, and partial coherence. Benchmarking tests show image contrast above 75% for 100-nm mask features, and significant improvements and across the full range of measured sizes. The zoneplate lens has been replaced by an array of user-selectable zoneplates with higher magnification and NA values up to 0.0875, emulating the spatial resolution of a 0.35-NA 4 x EUV stepper. Illumination uniformity is above 90% for mask areas 2-{micro}m-wide and smaller. An angle-scanning mirror reduces the high coherence of the synchrotron beamline light source giving measured {sigma} values of approximately 0.125 at 0.0875 NA.

  13. Actinic EUV mask inspection beyond 0.25 NA

    SciTech Connect

    Goldberg, Kenneth A.; Mochi, Iacopo; Anderson, Erik H.; Rekawa, Seno. B.; Kemp, Charles D.; Huh, S.; Han, H.-S.; Naulleau, P.; Huh, S.

    2008-03-24

    The SEMATECH Berkeley Actinic Inspection Tool (AIT) is an EUV-wavelength mask inspection microscope designed for direct aerial image measurements, and pre-commercial EUV mask research. Operating on a synchrotron bending magnet beamline, the AIT uses an off-axis Fresnel zoneplate lens to project a high-magnification EUV image directly onto a CCD camera. We present the results of recent system upgrades that have improved the imaging resolution, illumination uniformity, and partial coherence. Benchmarking tests show image contrast above 75% for 100-nm mask features, and significant improvements and across the full range of measured sizes. The zoneplate lens has been replaced by an array of user-selectable zoneplates with higher magnification and NA values up to 0.0875, emulating the spatial resolution of a 0.35-NA 4x EUV stepper. Illumination uniformity is above 90% for mask areas 2-{micro}m-wide and smaller. An angle-scanning mirror reduces the high coherence of the synchrotron beamline light source giving measured {sigma} values of approximately 0.125 at 0.0875 NA.

  14. Extracellular Na+ levels regulate formation and activity of the NaX/alpha1-Na+/K+-ATPase complex in neuronal cells

    PubMed Central

    Berret, Emmanuelle; Smith, Pascal Y.; Henry, Mélaine; Soulet, Denis; Hébert, Sébastien S.; Toth, Katalin; Mouginot, Didier; Drolet, Guy

    2014-01-01

    MnPO neurons play a critical role in hydromineral homeostasis regulation by acting as sensors of extracellular sodium concentration ([Na+]out). The mechanism underlying Na+-sensing involves Na+-flow through the NaX channel, directly regulated by the Na+/K+-ATPase α1-isoform which controls Na+-influx by modulating channel permeability. Together, these two partners form a complex involved in the regulation of intracellular sodium ([Na+]in). Here we aim to determine whether environmental changes in Na+ could actively modulate the NaX/Na+/K+-ATPase complex activity. We investigated the complex activity using patch-clamp recordings from rat MnPO neurons and Neuro2a cells. When the rats were fed with a high-salt-diet, or the [Na+] in the culture medium was increased, the activity of the complex was up-regulated. In contrast, drop in environmental [Na+] decreased the activity of the complex. Interestingly under hypernatremic condition, the colocalization rate and protein level of both partners were up-regulated. Under hyponatremic condition, only NaX protein expression was increased and the level of NaX/Na+/K+-ATPase remained unaltered. This unbalance between NaX and Na+/K+-ATPase pump proportion would induce a bigger portion of Na+/K+-ATPase-control-free NaX channel. Thus, we suggest that hypernatremic environment increases NaX/Na+/K+-ATPase α1-isoform activity by increasing the number of both partners and their colocalization rate, whereas hyponatremic environment down-regulates complex activity via a decrease in the relative number of NaX channels controlled by the pump. PMID:25538563

  15. Class 1 Areas

    EPA Pesticide Factsheets

    A Class 1 area is a geographic area recognized by the EPA as being of the highest environmental quality and requiring maximum protection. Class I areas are areas of special national or regional scenic, recreational or historic value for which the Prevention of Significant Deterioration (PSD) regulations provide special protection. These data were compiled based on EPA's list of mandatory Class I areas and Region 8 listing of non-mandatory Class 1 areas for three tribes. Spatial data are from National Park Service, U.S. Forest Service, U.S. Fish and Wildlife, and U.S. Census Bureau.

  16. Laser-induced ionization of Na vapor

    SciTech Connect

    Wu, R.C.Y.; Judge, D.L.; Roussel, F.; Carre, B.; Breger, P.; Spiess, G.

    1982-01-01

    The production of Na/sub 2//sup +/ ions by off-resonant laser excitation in the 5800-6200A region mainly results from two-photon absorption by the Na/sub 2/ molecule to highly excited gerade states followed by (a) direct ionization by absorbing a third photon or (b) coupling to the molecular Na/sub 2/ D/sup 1/PI..mu.. Rydberg state which is subsequently ionized by absorbing a third photon. This mechanism, i.e., a two-photon resonance three photon ionization process, explains a recent experimental observation of Roussel et al. It is suggested that the very same mechanism is also responsible for a similar observation reported by Polak-Dingels et al in their work using two crossed Na beams. In the latter two studies the laser-induced associative ionization processes were reported to be responsible for producing the Na/sub 2//sup +/ ion. From the ratio of molecular to atomic concentration in the crossed beam experiment of Polak-Dingels et al we estimate that the cross section for producing Na/sub 2//sup +/ through laser-induced associative ionization is at least four orders of magnitude smaller than ionization through the two-photon resonance three photon ionization process in Na/sub 2/ molecules.

  17. Laser-induced ionization of Na vapor

    NASA Astrophysics Data System (ADS)

    Wu, C. Y. Robert; Judge, D. L.; Roussel, F.; Carré, B.; Breger, P.; Spiess, G.

    1982-09-01

    The production of Na2+ ions by off-resonant laser excitation in the 5800-6200Å region mainly results from two-photon absorption by the Na2 molecule to highly excited gerade states followed by (a) direct ionization by absorbing a third photon or (b) coupling to the molecular Na2 D1Πu Rydberg state which is subsequently ionized by absorbing a third photon. This mechanism, i.e., a two-photon resonance three photon ionization process, explains a recent experimental observation of Roussel et al. It is suggested that the very same mechanism is also responsible for a similar observation reported by Polak-Dingels et al in their work using two crossed Na beams. In the latter two studies the laser-induced associative ionization processes were reported to be responsible for producing the Na2+ ion. From the ratio of molecular to atomic concentration in the crossed beam experiment of Polak-Dingels et al. we estimate that the cross section for producing Na2+ through laser-induced associative ionization is at least four orders of magnitude smaller than ionization through the two-photon resonance three photon ionization process in Na2 molecules.

  18. Additive effects of Na+ and Cl- ions on barley growth under salinity stress.

    PubMed

    Tavakkoli, Ehsan; Fatehi, Foad; Coventry, Stewart; Rengasamy, Pichu; McDonald, Glenn K

    2011-03-01

    Soil salinity affects large areas of the world's cultivated land, causing significant reductions in crop yield. Despite the fact that most plants accumulate both sodium (Na(+)) and chloride (Cl(-)) ions in high concentrations in their shoot tissues when grown in saline soils, most research on salt tolerance in annual plants has focused on the toxic effects of Na(+) accumulation. It has previously been suggested that Cl(-) toxicity may also be an important cause of growth reduction in barley plants. Here, the extent to which specific ion toxicities of Na(+) and Cl(-) reduce the growth of barley grown in saline soils is shown under varying salinity treatments using four barley genotypes differing in their salt tolerance in solution and soil-based systems. High Na(+), Cl(-), and NaCl separately reduced the growth of barley, however, the reductions in growth and photosynthesis were greatest under NaCl stress and were mainly additive of the effects of Na(+) and Cl(-) stress. The results demonstrated that Na(+) and Cl(-) exclusion among barley genotypes are independent mechanisms and different genotypes expressed different combinations of the two mechanisms. High concentrations of Na(+) reduced K(+) and Ca(2+) uptake and reduced photosynthesis mainly by reducing stomatal conductance. By comparison, high Cl(-) concentration reduced photosynthetic capacity due to non-stomatal effects: there was chlorophyll degradation, and a reduction in the actual quantum yield of PSII electron transport which was associated with both photochemical quenching and the efficiency of excitation energy capture. The results also showed that there are fundamental differences in salinity responses between soil and solution culture, and that the importance of the different mechanisms of salt damage varies according to the system under which the plants were grown.

  19. Sodium dichloroisocyanurate (NaDCC) tablets as an alternative to sodium hypochlorite for the routine treatment of drinking water at the household level.

    PubMed

    Clasen, Thomas; Edmondson, Paul

    2006-03-01

    Household water treatment using sodium hypochlorite (NaOCl) has been recognized as a cost-effective means of reducing the heavy burden of diarrhea and other waterborne diseases, especially among populations without access to improved water supplies. Sodium dichloroisocyanurate (NaDCC), which is widely used in emergencies, is an alternative source of chlorine that may present certain advantages over NaOCl for household-based interventions in development settings. We summarize the basic chemistry and possible benefits of NaDCC, and review the available literature concerning its safety and regulatory treatment and microbiological effectiveness. We review the evidence concerning NaDCC in field studies, including microbiological performance and health outcomes. Finally, we examine studies and data to compare NaDCC with NaOCl in terms of compliance, acceptability, affordability and sustainability, and suggest areas for further research.

  20. Should Broca's area include Brodmann area 47?

    PubMed

    Ardila, Alfredo; Bernal, Byron; Rosselli, Monica

    2017-02-01

    Understanding brain organization of speech production has been a principal goal of neuroscience. Historically, brain speech production has been associated with so-called Broca’s area (Brodmann area –BA- 44 and 45), however, modern neuroimaging developments suggest speech production is associated with networks rather than with areas. The purpose of this paper was to analyze the connectivity of BA47 ( pars orbitalis) in relation to language . A meta-analysis was conducted to assess the language network in which BA47 is involved. The Brainmap database was used. Twenty papers corresponding to 29 experimental conditions with a total of 373 subjects were included. Our results suggest that BA47 participates in a “frontal language production system” (or extended Broca’s system). The BA47  connectivity found is also concordant with a minor role in language semantics. BA47 plays a central role in the language production system.

  1. SUGARLOAF ROADLESS AREA, NEVADA.

    USGS Publications Warehouse

    McKee, Edwin H.; Schmauch, Steven W.

    1984-01-01

    On the basis of a mineral survey local areas in and near the western edge of the Sugarloaf Roadless Area, Nevada have probable resource potential for silver and small amounts of associated lead, zinc, and gold.

  2. NMR studies on Na+ transport in Synechococcus PCC 6311

    NASA Technical Reports Server (NTRS)

    Nitschmann, W. H.; Packer, L.

    1992-01-01

    The freshwater cyanobacterium Synechococcus PCC 6311 is able to adapt to grow after sudden exposure to salt (NaCl) stress. We have investigated the mechanism of Na+ transport in these cells during adaptation to high salinity. Na+ influx under dark aerobic conditions occurred independently of delta pH or delta psi across the cytoplasmic membrane, ATPase activity, and respiratory electron transport. These findings are consistent with the existence of Na+/monovalent anion cotransport or simultaneous Na+/H+ +anion/OH- exchange. Na+ influx was dependent on Cl-, Br-, NO3-, or NO2-. No Na+ uptake occurred after addition of NaI, NaHCO3, or Na2SO4. Na+ extrusion was absolutely dependent on delta pH and on an ATPase activity and/or on respiratory electron transport. This indicates that Na+ extrusion via Na+/H+ exchange is driven by primary H+ pumps in the cytoplasmic membrane. Cells grown for 4 days in 0.5 m NaCl medium, "salt-grown cells," differ from control cells by a lower maximum velocity of Na+ influx and by lower steady-state ratios of [Na+]in/[Na+]out. These results indicate that cells grown in high-salt medium increase their capacity to extrude Na+. During salt adaptation Na+ extrusion driven by respiratory electron transport increased from about 15 to 50%.

  3. Myocardial Na,K-ATPase: Clinical aspects

    PubMed Central

    Kjeldsen, Keld

    2003-01-01

    The specific binding of digitalis glycosides to Na,K-ATPase is used as a tool for Na,K-ATPase quantification with high accuracy and precision. In myocardial biopsies from patients with heart failure, total Na,K-ATPase concentration is decreased by around 40%; a correlation exists between a decrease in heart function and a decrease in Na,K-ATPase concentration. During digitalization, around 30% of remaining pumps are occupied by digoxin. Myocardial Na,K-ATPase is also influenced by other drugs used for the treatment of heart failure. Thus, potassium loss during diuretic therapy has been found to reduce myocardial Na,K-ATPase, whereas angiotensin-converting enzyme inhibitors may stimulate Na,K pump activity. Furthermore, hyperaldosteronism induced by heart failure has been found to decrease Na,K-ATPase activity. Accordingly, treatment with the aldosterone antagonist, spironolactone, may also influence Na,K-ATPase activity. The importance of Na,K pump modulation with heart disease, inhibition in digitalization and other effects of medication should be considered in the context of sodium, potassium and calcium regulation. It is recommended that digoxin be administered to heart failure patients who, after institution of mortality-reducing therapy, still have heart failure symptoms, and that the therapy be continued if symptoms are revealed or reduced. Digitalis glycosides are the only safe inotropic drugs for oral use that improve hemodynamics in heart failure. An important aspect of myocardial Na,K pump affection in heart disease is its influence on extracellular potassium (Ke) homeostasis. Two important aspects should be considered: potassium handling among myocytes, and effects of potassium entering the extracellular space of the heart via the bloodstream. It should be noted that both of these aspects of Ke homeostasis are affected by regulatory aspects, eg, regulation of the Na,K pump by physiological and pathophysiological conditions, as well as by medical

  4. RATTLESNAKE ROADLESS AREA, ARIZONA.

    USGS Publications Warehouse

    Karlstrom, Thor N.V.; McColly, Robert

    1984-01-01

    There is little promise for the occurrence of mineral or energy resources in the Rattlesnake Roadless Area, Arizona, as judged from field studies. Significant concentrations of minerals within the roadless area are not indicated by geologic mapping, geochemical sampling, or aeromagnetic studies. Basalt, volcanic cinders, sand and gravel, and sandstone that may be suitable for construction materials occur in the area, but are more readily accessible outside the roadless area boundary.

  5. The Ethiopean Language Area.

    ERIC Educational Resources Information Center

    Ferguson, Charles A.

    This paper constitutes the fifth chapter of the forthcoming volume "Language in Ethiopia." In an effort to better define the particular linguistic area, the author analyzes phonological and grammatical features that languages in the area have in common. A number of features have been identified as characteristic of the area, and this…

  6. Developing Environmental Study Areas.

    ERIC Educational Resources Information Center

    Wert, Jonathan M.

    This publication is designed to help the teacher in developing environmental study areas. Numerous examples of study areas, including airports, lakes, shopping centers, and zoos, are listed. A current definition of environmental study areas is given and guidelines for their development and identification are included. The appendix, which comprises…

  7. Self-assembled cabbage-like NaInS{sub 2} microstructures with efficient visible light photocatalytic performance

    SciTech Connect

    Gao, Yuanhao Zhai, Xuezhen; Zhang, Yange; Xu, Zhihong; Li, Pinjiang; Zheng, Zhi

    2013-07-15

    Cabbage-like NaInS{sub 2} microstructures have been synthesized by reacting In(NO{sub 3}){sub 3} with the alkaline sulfur aqueous solution of NaOH in a simple hydrothermal process without any shape-directing surfactants. The cabbage-like NaInS{sub 2} architectures are monodispersed in large quantities. The cabbage-like morphologies depend strongly on the different ratios of S powder to NaOH, the reaction temperature and reaction time. The possible growth mechanism for the formation of cabbage-like NaInS{sub 2} architectures is discussed. The cabbage-like NaInS{sub 2} architectures exhibit the superiority of photocatalytic performance for the photodegradation of RhB irradiation under visible light irradiation. It is believed that the photocatalytic superiority of the cabbage-like NaInS{sub 2} architectures is mainly due to their special surface areas and inner interconnected structural features. - Graphical abstract: Cabbage-like NaInS{sub 2} microstructures were facilely synthesized via simple hydrothermal reaction. The cabbage-like NaInS{sub 2} architectures exhibit the superiority of photocatalytic performance for the photodegradation of RhB irradiation under visible light irradiation. - Highlights: • Cabbage-like NaInS{sub 2} microstructures were facilely synthesized via a hydrothermal reaction. • Influencing parameters on the NaInS{sub 2} morphologies have been discussed in detail. • The cabbage-like NaInS{sub 2} architectures hold efficient photocatalytic performance. • The photocatalytic superiority is mainly due to their special structural features.

  8. Characteristics and pharmacological regulation of epithelial Na+ channel (ENaC) and epithelial Na+ transport.

    PubMed

    Marunaka, Yoshinori

    2014-01-01

    Epithelial Na(+) transport participates in control of various body functions and conditions: e.g., homeostasis of body fluid content influencing blood pressure, control of amounts of fluids covering the apical surface of alveolar epithelial cells at appropriate levels for normal gas exchange, and prevention of bacterial/viral infection. Epithelial Na(+) transport via the transcellular pathway is mediated by the entry step of Na(+) across the apical membrane via Epithelial Na(+) Channel (ENaC) located at the apical membrane, and the extrusion step of Na(+) across the basolateral membrane via the Na(+),K(+)-ATPase located at the basolateral membrane. The rate-limiting step of the epithelial Na(+) transport via the transcellular pathway is generally recognized to be the entry step of Na(+) across the apical membrane via ENaC. Thus, up-/down-regulation of ENaC essentially participates in regulatory systems of blood pressure and normal gas exchange. Amount of ENaC-mediated Na(+) transport is determined by the number of ENaCs located at the apical membrane, activity (open probability) of individual ENaC located at the apical membrane, single channel conductance of ENaC located at the apical membrane, and driving force for the Na(+) entry via ENaCs across the apical membrane. In the present review article, I discuss the characteristics of ENaC and how these factors are regulated.

  9. Computational and Experimental Investigations of Na-Ion Conduction in Cubic Na3PSe4

    DOE PAGES

    Bo, Shou -Hang; Wang, Yan; Kim, Jae Chul; ...

    2015-11-17

    All-solid-state Na-ion batteries that operate at or close to room temperature are a promising next-generation battery technology with enhanced safety and reduced manufacturing cost. An indispensable component of this technology is the solid-state electrolyte that allows rapid shuttling of the mobile cation (i.e., Na+) between the cathode and anode. However, there are very few fast Na-ion conductors with ionic conductivity approaching that of the liquid counterparts (i.e., 1 mS cm–1). In this work, we present the synthesis and characterization of a fast Na-ion conductor, cubic Na3PSe4. This material possesses a room-temperature ionic conductivity exceeding 0.1 mS cm–1 and does notmore » require high-temperature sintering to minimize grain boundary resistance, making it a promising solid-state electrolyte candidate for all-solid-state Na-ion battery applications. On the basis of density functional theory, nudged elastic band, and molecular dynamics investigations, we demonstrate that the framework of cubic Na3PSe4 only permits rapid Na+ diffusion with the presence of defects, and that the formation of the Na vacancy (charge-balanced by slight Se2– oxidation) is more energetically favorable among the various defects considered. This finding provides important guidelines to further improve Na-ion conductivity in this class of materials.« less

  10. Glutathionylation-Dependence of Na(+)-K(+)-Pump Currents Can Mimic Reduced Subsarcolemmal Na(+) Diffusion.

    PubMed

    Garcia, Alvaro; Liu, Chia-Chi; Cornelius, Flemming; Clarke, Ronald J; Rasmussen, Helge H

    2016-03-08

    The existence of a subsarcolemmal space with restricted diffusion for Na(+) in cardiac myocytes has been inferred from a transient peak electrogenic Na(+)-K(+) pump current beyond steady state on reexposure of myocytes to K(+) after a period of exposure to K(+)-free extracellular solution. The transient peak current is attributed to enhanced electrogenic pumping of Na(+) that accumulated in the diffusion-restricted space during pump inhibition in K(+)-free extracellular solution. However, there are no known physical barriers that account for such restricted Na(+) diffusion, and we examined if changes of activity of the Na(+)-K(+) pump itself cause the transient peak current. Reexposure to K(+) reproduced a transient current beyond steady state in voltage-clamped ventricular myocytes as reported by others. Persistence of it when the Na(+) concentration in patch pipette solutions perfusing the intracellular compartment was high and elimination of it with K(+)-free pipette solution could not be reconciled with restricted subsarcolemmal Na(+) diffusion. The pattern of the transient current early after pump activation was dependent on transmembrane Na(+)- and K(+) concentration gradients suggesting the currents were related to the conformational poise imposed on the pump. We examined if the currents might be accounted for by changes in glutathionylation of the β1 Na(+)-K(+) pump subunit, a reversible oxidative modification that inhibits the pump. Susceptibility of the β1 subunit to glutathionylation depends on the conformational poise of the Na(+)-K(+) pump, and glutathionylation with the pump stabilized in conformations equivalent to those expected to be imposed on voltage-clamped myocytes supported this hypothesis. So did elimination of the transient K(+)-induced peak Na(+)-K(+) pump current when we included glutaredoxin 1 in patch pipette solutions to reverse glutathionylation. We conclude that transient K(+)-induced peak Na(+)-K(+) pump current reflects the effect

  11. Catalysis of Na+ permeation in the bacterial sodium channel NaVAb

    PubMed Central

    Chakrabarti, Nilmadhab; Ing, Christopher; Payandeh, Jian; Zheng, Ning; Catterall, William A.; Pomès, Régis

    2013-01-01

    Determination of a high-resolution 3D structure of voltage-gated sodium channel NaVAb opens the way to elucidating the mechanism of ion conductance and selectivity. To examine permeation of Na+ through the selectivity filter of the channel, we performed large-scale molecular dynamics simulations of NaVAb in an explicit, hydrated lipid bilayer at 0 mV in 150 mM NaCl, for a total simulation time of 21.6 μs. Although the cytoplasmic end of the pore is closed, reversible influx and efflux of Na+ through the selectivity filter occurred spontaneously during simulations, leading to equilibrium movement of Na+ between the extracellular medium and the central cavity of the channel. Analysis of Na+ dynamics reveals a knock-on mechanism of ion permeation characterized by alternating occupancy of the channel by 2 and 3 Na+ ions, with a computed rate of translocation of (6 ± 1) × 106 ions⋅s−1 that is consistent with expectations from electrophysiological studies. The binding of Na+ is intimately coupled to conformational isomerization of the four E177 side chains lining the extracellular end of the selectivity filter. The reciprocal coordination of variable numbers of Na+ ions and carboxylate groups leads to their condensation into ionic clusters of variable charge and spatial arrangement. Structural fluctuations of these ionic clusters result in a myriad of ion binding modes and foster a highly degenerate, liquid-like energy landscape propitious to Na+ diffusion. By stabilizing multiple ionic occupancy states while helping Na+ ions diffuse within the selectivity filter, the conformational flexibility of E177 side chains underpins the knock-on mechanism of Na+ permeation. PMID:23803856

  12. Interaction between Na+ and H+ ions on Na-H exchange in sheep cardiac Purkinje fibers.

    PubMed

    Wu, M L; Vaughan-Jones, R D

    1997-04-01

    The interaction between Na+ and H+ ions upon Na-H exchange (NHE) was examined in sheep cardiac Purkinje fibers. Acid equivalent fluxes through NHE were examined using recordings of intracellular pH and Na+ in isolated preparations measured with ion selective microelectrodes. The extent of acid-extrusion by NHE was estimated from pH(i) recovery-rate, multiplied by beta(i) (intracellular buffering power) in response to an internal acid load induced by 20 mm NH4Cl removal (nominally HCO3- free media). A mixed inhibitory effect was found of extracellular H+ on external Na+-activation of NHE (i.e. an increase, at low pH(o), in the apparent Michaelis constant for external Na+ ions [K(Nao)(0.5)] and a decrease in the maximum transport rate [V(Nao)(max)]). In addition, we confirmed that the stoichiometry of Na(o) binding is unaffected by the pH(o) (between 7.5 and 6.5), showing a Hill coefficient close to one. The interaction between Na+ and H+ ions at the internal face of the cardiac NHE was also studied. Our evidence suggests that an increase in the intracellular Na+ ion concentration ([Na+]i) inhibits acid efflux and that this inhibition can be approximated by the decrease in thermodynamic driving force caused by reducing the transmembrane Na+ gradient. It appears, however, that small variations in [Na+]i from the normal resting level (intracellular sodium activity, a(i)Na = 7 to 13 mm) have little or no effect on acid efflux, suggesting that variation of a(i)Na is not a physiologically important controller of NHE activity in heart.

  13. Glutathionylation-Dependence of Na+-K+-Pump Currents Can Mimic Reduced Subsarcolemmal Na+ Diffusion

    PubMed Central

    Garcia, Alvaro; Liu, Chia-Chi; Cornelius, Flemming; Clarke, Ronald J.; Rasmussen, Helge H.

    2016-01-01

    The existence of a subsarcolemmal space with restricted diffusion for Na+ in cardiac myocytes has been inferred from a transient peak electrogenic Na+-K+ pump current beyond steady state on reexposure of myocytes to K+ after a period of exposure to K+-free extracellular solution. The transient peak current is attributed to enhanced electrogenic pumping of Na+ that accumulated in the diffusion-restricted space during pump inhibition in K+-free extracellular solution. However, there are no known physical barriers that account for such restricted Na+ diffusion, and we examined if changes of activity of the Na+-K+ pump itself cause the transient peak current. Reexposure to K+ reproduced a transient current beyond steady state in voltage-clamped ventricular myocytes as reported by others. Persistence of it when the Na+ concentration in patch pipette solutions perfusing the intracellular compartment was high and elimination of it with K+-free pipette solution could not be reconciled with restricted subsarcolemmal Na+ diffusion. The pattern of the transient current early after pump activation was dependent on transmembrane Na+- and K+ concentration gradients suggesting the currents were related to the conformational poise imposed on the pump. We examined if the currents might be accounted for by changes in glutathionylation of the β1 Na+-K+ pump subunit, a reversible oxidative modification that inhibits the pump. Susceptibility of the β1 subunit to glutathionylation depends on the conformational poise of the Na+-K+ pump, and glutathionylation with the pump stabilized in conformations equivalent to those expected to be imposed on voltage-clamped myocytes supported this hypothesis. So did elimination of the transient K+-induced peak Na+-K+ pump current when we included glutaredoxin 1 in patch pipette solutions to reverse glutathionylation. We conclude that transient K+-induced peak Na+-K+ pump current reflects the effect of conformation-dependent β1 pump subunit

  14. CHATTAHOOCHEE ROADLESS AREA, GEORGIA.

    USGS Publications Warehouse

    Nelson, Arthur E.; Welsh, Robert A.

    1984-01-01

    A mineral survey indicates that the Chattahoochee Roadless Area, Georgia, offers little promise for the occurrence of mineral resources even though gold, mica, sillimanite, soapstone, dunite, chromite, and nickel have been mined nearby, and source rocks for these commodities are present in the roadless area. Granite gneiss, gneiss, schist, and metasandstone in the roadless area are suitable for stone, crushed rock, or aggregate; however, other sources for these materials are available outside the roadless area, closer to present markets. The potential for the occurrence of hydrocarbons (probably gas) beneath the thick regional thrust sheets in this area cannot be adequately evaluated from available data.

  15. Thermodynamic Model for the Solubility of Cr(OH)(3)(am) in Concentrated NaOH and NaOH-NaNO3 Solutions

    SciTech Connect

    Rai, Dhanpat ); Hess, Nancy J. ); Rao, Linfeng; Zhang, Zhicheng; Felmy, Andrew R. ); Moore, Dean A. ); Clark, Sue B.; Lumetta, Gregg J. )

    2001-12-01

    The objectives of this study were to develop a reliable thermodynamic model for predicting Cr(III) behavior in concentrated NaOH and in mixed NaOH-NaNO3 solutions for application to effective caustic leaching strategies for high-level tank sludges. To meet these objectives, the solubility of Cr(OH)3(am) was measured in 0.003 to 10.5 m NaOH, 3.0 m es in NaOH concentration...

  16. Erythrocyte 22Na+ influx in hypertension

    SciTech Connect

    Shalev, O.; Eaton, J.W.; Ben-Ishay, D.

    1984-01-01

    We assessed 22Na+ uptake by erythrocytes (RBC) from 38 individuals with essential hypertension and 37 healthy controls. All subjects were male, white, non-obese and with normal renal function, obviating sex, race, hormonal, ponderal and renal factors known to influence RBC Na+ handling. The mean +/- sem 22Na+ uptake of the patients was 284 +/- 16 mumole/liter RBC/hour while that of normal controls was 249 +/- 11 mumole/liter RBC/hour; although the difference reached borderline significance, individual values showed considerable overlap. Consequently, in our population, RBC 22Na+ uptake is not a reliable marker for essential hypertension. We believe that previous studies should be reassessed with regard to patients' characteristics and future studies employ rigorous criteria in selection of subjects.

  17. TROUBLESOME ROADLESS AREA, KENTUCKY.

    USGS Publications Warehouse

    Sigleo, W.R.; Hammack, R.W.

    1984-01-01

    A mineral-resource survey identified resources of coal, oil and gas, sandstone, and shale in the Troublesome Roadless Area, Kentucky. Demonstrated resources of approximately 429,100 short tons of coal in an area of substantiated resource potential are contained in two major coal beds more than 28 in. thick and the area also contains an additional 483,900 short tons of coal in beds between 14 and 28 in. thick. A probable potential for oil and gas is assigned to the entire area as these fuels may be present in underlying rocks of Mississippian age. Sandstone for silica sand, construction sand, and dimension stone, and shale for structural clay products occur in the area, but these commodities also occur in abundance outside the roadless area. A geochemical survey indicates that there is little promise for the occurrence of metallic mineral resources in the roadless area.

  18. MADISON ROADLESS AREA, MONTANA.

    USGS Publications Warehouse

    Simons, Frank S.; Lambeth, Robert H.

    1984-01-01

    A mineral-resource survey of the Madison Roadless Area in the Madison Range of southwestern Montana was made. The Madison Roadless Area has demonstrated resources of about 93,000 tons of sillimanite rock at the Placer Creek deposit and of about 83,000 tons of asbestos rock at the Karst deposit. The roadless area also has areas of substantiated phosphate resource potential; much of the phosphate is in thin deeply buried beds. An area near the south edge of the roadless area has a probable resource potential for copper and silver. The concentration of uranium-rich stream-sediment samples in the southwest part of the roadless area suggests that a further attempt to identify the source rocks might be justified.

  19. Molecular dynamics simulation of NaCl dissolution.

    PubMed

    Lanaro, Gabriele; Patey, G N

    2015-03-19

    Molecular dynamics simulations are used to investigate the dissolution of NaCl nanocrystals (containing ∼2400 ions) in water. We focus on systems under sink conditions at 300 K, but the influences of concentration and temperature are also investigated. Cubical, spherical, tablet-shaped, and rod-shaped nanocrystals are considered, and it is shown that the initial shape can influence the dissolution process. Dissolution is observed to occur in three stages: an initial period where the most exposed ions are removed from the crystal surface, and the crystal takes on a solution-annealed shape which persists throughout the second stage of dissolution; a second long intermediate stage where dissolution roughly follows a fixed rate law; and a final stage where the small residual crystal (≲200 ions) dissolves at an ever increasing rate until it disappears. The second stage of dissolution which applies for most of the dissolution process is well described by classical rate equations which simply assume that the dissolution rate is proportional to an active surface area from which ions are most easily detached from the crystal. The active area depends on the initial crystal shape. We show that for our model NaCl nanocrystals the rate-determining step for dissolution under sink conditions is ion detachment from the crystal, and that diffusion layers do not exist for these systems.

  20. Hydrogen-fluorine exchange in NaBH4-NaBF4.

    PubMed

    Rude, L H; Filsø, U; D'Anna, V; Spyratou, A; Richter, B; Hino, S; Zavorotynska, O; Baricco, M; Sørby, M H; Hauback, B C; Hagemann, H; Besenbacher, F; Skibsted, J; Jensen, T R

    2013-11-07

    Hydrogen-fluorine exchange in the NaBH4-NaBF4 system is investigated using a range of experimental methods combined with DFT calculations and a possible mechanism for the reactions is proposed. Fluorine substitution is observed using in situ synchrotron radiation powder X-ray diffraction (SR-PXD) as a new Rock salt type compound with idealized composition NaBF2H2 in the temperature range T = 200 to 215 °C. Combined use of solid-state (19)F MAS NMR, FT-IR and DFT calculations supports the formation of a BF2H2(-) complex ion, reproducing the observation of a (19)F chemical shift at -144.2 ppm, which is different from that of NaBF4 at -159.2 ppm, along with the new absorption bands observed in the IR spectra. After further heating, the fluorine substituted compound becomes X-ray amorphous and decomposes to NaF at ~310 °C. This work shows that fluorine-substituted borohydrides tend to decompose to more stable compounds, e.g. NaF and BF3 or amorphous products such as closo-boranes, e.g. Na2B12H12. The NaBH4-NaBF4 composite decomposes at lower temperatures (300 °C) compared to NaBH4 (476 °C), as observed by thermogravimetric analysis. NaBH4-NaBF4 (1:0.5) preserves 30% of the hydrogen storage capacity after three hydrogen release and uptake cycles compared to 8% for NaBH4 as measured using Sievert's method under identical conditions, but more than 50% using prolonged hydrogen absorption time. The reversible hydrogen storage capacity tends to decrease possibly due to the formation of NaF and Na2B12H12. On the other hand, the additive sodium fluoride appears to facilitate hydrogen uptake, prevent foaming, phase segregation and loss of material from the sample container for samples of NaBH4-NaF.

  1. Deliquescence of NaCl-NaNO3, KNO3-NaNO3, and NaCl-KNO3 Salt Mixtures From 90 to 120?C

    SciTech Connect

    Carroll, S A; Craig, L; Wolery, T J

    2004-10-20

    We conducted reversed deliquescence experiments in saturated NaCl-NaNO{sub 3}-H{sub 2}O, KNO{sub 3}-NaNO{sub 3}-H{sub 2}O, and NaCl-KNO{sub 3}-H{sub 2}O systems from 90 to 120 C as a function of relative humidity and solution composition. NaCl, NaNO{sub 3}, and KNO{sub 3} represent members of dust salt assemblages that are likely to deliquesce and form concentrated brines on high-level radioactive waste package surfaces in a repository environment at Yucca Mountain, NV, USA. Discrepancy between model prediction and experimental code can be as high as 8% for relative humidity and 50% for dissolved ion concentration. The discrepancy is attributed primarily to the use of 25 C models for Cl-NO{sub 3} and K-NO{sub 3} ion interactions in the current Yucca Mountain Project high-temperature Pitzer model to describe the non-ideal behavior of these highly concentrated solutions.

  2. Concentration Dependence of NaCl ion distributions around DPPC lipid bilayers

    PubMed Central

    Rodriguez, Jorge R.; García, Angel E.

    2012-01-01

    We study the coordination of excess NaCl to zwitterionic DPPC lipid bilayers using molecular dynamics simulations. We find that Na ions directly coordinate with the DPPC lipid carbonyl groups. As the number of excess ions increases, the number of coordinated ions increases, until it reaches a plateau at a ratio near 1 ion per every four lipids at 310 K, and 1 ion per every six lipids at 323 K. The area per lipid decreases as the number of excess ions is increased. For low number of ions per lipids (1:16 and 1:8), most Na ions are bound to the lipid carbonyls, while the Cl form an ionic cloud around the lipid choline groups. As a result of the Na binding, the lipid has an effective positive charge density. The residence time of Na ions bound to the lipid is longer than 40 ns, while Cl ions exchange faster than the nanoseconds timescale. We find that the bound Na ions replace ordered water around the carbonyls. The net linear charge density near the carbonyl groups stays positive, regardless of the presence of excess salt in the solution. PMID:22179761

  3. Prolonged Intracellular Na+ Dynamics Govern Electrical Activity in Accessory Olfactory Bulb Mitral Cells

    PubMed Central

    Zylbertal, Asaph; Kahan, Anat; Ben-Shaul, Yoram; Yarom, Yosef; Wagner, Shlomo

    2015-01-01

    Persistent activity has been reported in many brain areas and is hypothesized to mediate working memory and emotional brain states and to rely upon network or biophysical feedback. Here, we demonstrate a novel mechanism by which persistent neuronal activity can be generated without feedback, relying instead on the slow removal of Na+ from neurons following bursts of activity. We show that mitral cells in the accessory olfactory bulb (AOB), which plays a major role in mammalian social behavior, may respond to a brief sensory stimulation with persistent firing. By combining electrical recordings, Ca2+ and Na+ imaging, and realistic computational modeling, we explored the mechanisms underlying the persistent activity in AOB mitral cells. We found that the exceptionally slow inward current that underlies this activity is governed by prolonged dynamics of intracellular Na+ ([Na+]i), which affects neuronal electrical activity via several pathways. Specifically, elevated dendritic [Na+]i reverses the Na+-Ca2+ exchanger activity, thus modifying the [Ca2+]i set-point. This process, which relies on ubiquitous membrane mechanisms, is likely to play a role in other neuronal types in various brain regions. PMID:26674618

  4. Theoretical study of Na-atom emission from NaCl (100) surfaces

    NASA Astrophysics Data System (ADS)

    Puchin, Vladimir; Shluger, Alexander; Nakai, Yasuo; Itoh, Noriaki

    1994-04-01

    Several models for the elementary processes causing the emission of alkali atoms by electronic excitation of NaCl (100) surfaces have been investigated theoretically. First, the desorption of a Na atom neighboring an electronically excited F center on the surface is simulated using a quantum-mechanical embedded-cluster technique. It is shown that emission of a Na atom is energetically favorable. The kinetics of this process is shown to be controlled by the probability of a nonradiative transition between the two states: the excited state of the F center and that corresponding to a Na atom desorbing from the surface. The potential barrier for desorption of an excited Na atom from the excited F-center state is found to be 2.1 eV. It is also found that the energy for emission of a Na atom from a cluster of F centers (the F3 center) is considerably reduced (for a certain configuration of the defect) with respect to the similar energy for a single F center. The energy barrier for emission of a Na atom neighboring an F' center on the surface is calculated to be 1 eV. It is shown that the electronic excitation of kinklike sites, with a Na atom at the edge, can lead to a barrierless emission of a Na atom, leaving a Vk-type defect behind. The results of calculations are discussed critically on the basis of existing experimental data.

  5. Glutamate Water Gates in the Ion Binding Pocket of Na(+) Bound Na(+), K(+)-ATPase.

    PubMed

    Han, Minwoo; Kopec, Wojciech; Solov'yov, Ilia A; Khandelia, Himanshu

    2017-01-13

    The dynamically changing protonation states of the six acidic amino acid residues in the ion binding pocket of the Na(+), K(+) -ATPase (NKA) during the ion transport cycle are proposed to drive ion binding, release and possibly determine Na(+) or K(+) selectivity. We use molecular dynamics (MD) and density functional theory (DFT) simulations to determine the protonation scheme of the Na(+) bound conformation of NKA. MD simulations of all possible protonation schemes show that the bound Na(+) ions are most stably bound when three or four protons reside in the binding sites, and that Glu954 in site III is always protonated. Glutamic acid residues in the three binding sites act as water gates, and their deprotonation triggers water entry to the binding sites. From DFT calculations of Na(+) binding energies, we conclude that three protons in the binding site are needed to effectively bind Na(+) from water and four are needed to release them in the next step. Protonation of Asp926 in site III will induce Na(+) release, and Glu327, Glu954 and Glu779 are all likely to be protonated in the Na(+) bound occluded conformation. Our data provides key insights into the role of protons in the Na(+) binding and release mechanism of NKA.

  6. Anion-coupled Na efflux mediated by the human red blood cell Na/K pump

    PubMed Central

    1990-01-01

    The red cell Na/K pump is known to continue to extrude Na when both Na and K are removed from the external medium. Because this ouabain- sensitive flux occurs in the absence of an exchangeable cation, it is referred to as uncoupled Na efflux. This flux is also known to be inhibited by 5 mM Nao but to a lesser extent than that inhibitable by ouabain. Uncoupled Na efflux via the Na/K pump therefore can be divided into a Nao-sensitive and Nao-insensitive component. We used DIDS- treated, SO4-equilibrated human red blood cells suspended in HEPES- buffered (pHo 7.4) MgSO4 or (Tris)2SO4, in which we measured 22Na efflux, 35SO4 efflux, and changes in the membrane potential with the fluorescent dye, diS-C3 (5). A principal finding is that uncoupled Na efflux occurs electroneurally, in contrast to the pump's normal electrogenic operation when exchanging Nai for Ko. This electroneutral uncoupled efflux of Na was found to be balanced by an efflux of cellular anions. (We were unable to detect any ouabain-sensitive uptake of protons, measured in an unbuffered medium at pH 7.4 with a Radiometer pH-STAT.) The Nao-sensitive efflux of Nai was found to be 1.95 +/- 0.10 times the Nao-sensitive efflux of (SO4)i, indicating that the stoichiometry of this cotransport is two Na+ per SO4=, accounting for 60-80% of the electroneutral Na efflux. The remainder portion, that is, the ouabain-sensitive Nao-insensitive component, has been identified as PO4-coupled Na transport and is the subject of a separate paper. That uncoupled Na efflux occurs as a cotransport with anions is supported by the result, obtained with resealed ghosts, that when internal and external SO4 was substituted by the impermeant anion, tartrate i,o, the efflux of Na was inhibited 60-80%. This inhibition could be relieved by the inclusion, before DIDS treatment, of 5 mM Cli,o. Addition of 10 mM Ko to tartrate i,o ghosts, with or without Cli,o, resulted in full activation of Na/K exchange and the pump's electrogenicity

  7. Glutamate Water Gates in the Ion Binding Pocket of Na+ Bound Na+, K+-ATPase

    PubMed Central

    Han, Minwoo; Kopec, Wojciech; Solov’yov, Ilia A.; Khandelia, Himanshu

    2017-01-01

    The dynamically changing protonation states of the six acidic amino acid residues in the ion binding pocket of the Na+, K+ -ATPase (NKA) during the ion transport cycle are proposed to drive ion binding, release and possibly determine Na+ or K+ selectivity. We use molecular dynamics (MD) and density functional theory (DFT) simulations to determine the protonation scheme of the Na+ bound conformation of NKA. MD simulations of all possible protonation schemes show that the bound Na+ ions are most stably bound when three or four protons reside in the binding sites, and that Glu954 in site III is always protonated. Glutamic acid residues in the three binding sites act as water gates, and their deprotonation triggers water entry to the binding sites. From DFT calculations of Na+ binding energies, we conclude that three protons in the binding site are needed to effectively bind Na+ from water and four are needed to release them in the next step. Protonation of Asp926 in site III will induce Na+ release, and Glu327, Glu954 and Glu779 are all likely to be protonated in the Na+ bound occluded conformation. Our data provides key insights into the role of protons in the Na+ binding and release mechanism of NKA. PMID:28084301

  8. Stoichiometry and Na+ binding cooperativity of rat and flounder renal type II Na+-Pi cotransporters.

    PubMed

    Forster, I C; Loo, D D; Eskandari, S

    1999-04-01

    The stoichiometry of the rat and flounder isoforms of the renal type II sodium-phosphate (Na+-Pi) cotransporter was determined directly by simultaneous measurements of phosphate (Pi)-induced inward current and uptake of radiolabeled Pi and Na+ in Xenopus laevis oocytes expressing the cotransporters. There was a direct correlation between the Pi-induced inward charge and Pi uptake into the oocytes; the slope indicated that one net inward charge was transported per Pi. There was also a direct correlation between the Pi-induced inward charge and Na+ influx; the slope indicated that the influx of three Na+ ions resulted in one net inward charge. This behavior was similar for both isoforms. We conclude that for both Na+-Pi cotransporter isoforms the Na+:Pi stoichiometry is 3:1 and that divalent Pi is the transported substrate. Steady-state activation of the currents showed that the Hill coefficients for Pi were unity for both isoforms, whereas for Na+, they were 1.8 (flounder) and 2.5 (rat). Therefore, despite significant differences in the apparent Na+ binding cooperativity, the estimated Na+:Pi stoichiometry was the same for both isoforms.

  9. Vascular contractile reactivity in hypotension due to reduced renal reabsorption of Na(+) and restricted dietary Na().

    PubMed

    Alshahrani, Saeed; Rapoport, Robert M; Soleimani, Manoocher

    2017-03-01

    Reduced renal Na(+) reabsorption along with restricted dietary Na(+) depletes intravascular plasma volume which can then result in hypotension. Whether hypotension occurs and the magnitude of hypotension depends in part on compensatory angiotensin II-mediated increased vascular resistance. We investigated whether the ability of vascular resistance to mitigate the hypotension was compromised by decreased contractile reactivity. In vitro reactivity was investigated in aorta from mouse models of reduced renal Na(+) reabsorption and restricted dietary Na(+) associated with considerable hypotension and renin-angiotensin system activation: (1) the Na(+)-Cl(-)-Co-transporter (NCC) knockout (KO) with Na(+) restricted diet (0.1%, 2 weeks) and (2) the relatively more severe pendrin (apical chloride/bicarbonate exchanger) and NCC double KO. Contractile sensitivity to KCl, phenylephrine, and/or U46619 remained unaltered in aorta from both models. Maximal KCl and phenylephrine contraction expressed as force/aorta length from NCC KO with Na(+)-restricted diet remained unaltered, while in pendrin/NCC double KO were reduced to 49 and 64%, respectively. Wet weight of aorta from NCC KO with Na(+)-restricted diet remained unaltered, while pendrin/NCC double KO was reduced to 67%, consistent with decreased medial width determined with Verhoeff-Van Gieson stain. These findings suggest that hypotension associated with severe intravascular volume depletion, as the result of decreased renal Na(+) reabsorption, may in part be due to decreased contractile reactivity as a consequence of reduced vascular hypertrophy.

  10. Glacier Primitive Area, Wyoming

    SciTech Connect

    Granger, H.C.; Patten, L.L.

    1984-01-01

    A mineral survey of the Glacier Primitive Area and an adjoining area to the northwest was made in 1968 and 1969. The study area was mapped geologically, an aeromagnetic survey was made, a geochemical study was done, and known mineralized occurrences and claims were examined. Two localities were found to contain small concentrations of uranium and several samples displayed minor anomalies in base and precious metals. A probable resource potential for lead, molybdenum, arsenic, barium, fluorite, and uranium exists in the area near the Ross Lakes shear zone and a small area of probable uranium resource potential exists around the Dubois claims. The study area, in general, is believed to have little promise for the occurrence of additional mineral or energy resources.

  11. WINCHESTER ROADLESS AREA, ARIZONA.

    USGS Publications Warehouse

    Keith, William J.; Kreidler, Terry J.

    1984-01-01

    The Winchester Roadless Area, located in northwestern Cochise County, Arizona, consists of 22 sq mi of Coronado National Forest in the Winchester Mountains. This study consisted of (1) field checking and modification of the existing geologic maps of the area, (2) field examination of all mines, prospects, and mineralized areas in and adjacent to the Winchester Roadless Area, (3) sampling of bedrock and stream sediments from drainage basins for geochemical analysis; and (4) examination and interpretation of available aeromagnetic and gravity data. Results of geologic, geochemical, geophysical, and mining activity and production surveys indicate little promise for the occurrence of metallic and nonmetallic or energy resources in the area. Volcanic rocks cover the area to a thickness of 1000 to 2000 ft and possibly more, thus preventing inspection and evaluation of the underlying rock.

  12. GLACIER PRIMITIVE AREA, WYOMING.

    USGS Publications Warehouse

    Granger, Harry C.; Patten, Lowell L.

    1984-01-01

    A mineral survey of the Glacier Primitive Area, Wyoming and an adjoining area to the northeast was made. The study area was mapped geologically, an aeromagnetic survey was made, a geochemical study was done, and known mineralized occurrences and claims were examined. Two localities were found to contain small concentrations of uranium and several samples displayed minor anomalies in base and precious metals. A probable resource potential for lead, molybdenum, arsenic, barium, fluorite, and uranium exists in the area near the Ross Lakes shear zone and a small area of probable uranium resource potential exists around the Dubois claims. The study area, in general, is believed to have little promise for the occurrence of additional mineral or energy resources.

  13. Influence of sodium halides (NaF, NaCl, NaBr, NaI) on the photocatalytic performance of hydrothermally synthesized hematite photoanodes.

    PubMed

    Wang, Tsinghai; Huang, Mao-Chia; Hsieh, Yi-Kong; Chang, Wen-Sheng; Lin, Jing-Chie; Lee, Chih-Hao; Wang, Chu-Fang

    2013-08-28

    It has been suggested that a high concentration of Fe(3+) in solution, a low pH, and noncomplexing ions of high ionic strength are all essential for developing a high-quality hematite array. Our curiosity was piqued regarding the role of the electrolyte ions in the hydrothermal synthesis of hematite photoanodes. In this study, we prepared hematite photoanodes hydrothermally from precursor solutions of 0.1 M FeCl3 at pH 1.55 with a background electrolyte of 1.0 M sodium halide (NaF, NaCl, NaBr, or NaI). We compared the structures and properties of the as-obtained hematite photoanodes with those of the material prepared in 1.0 M NaNO3, the most widely adopted electrolyte in previous studies. Among our studied systems, we found that the hematite photoanode prepared in NaCl solution was the only one possessing properties similar to those of the sample obtained from the NaNO3 solution-most importantly in terms of photoelectrochemical performance (ca. 0.2 mA/cm(2) with +0.4 V vs SCE). The hematites obtained from the NaF, NaBr, and NaI solutions exhibited much lower (by approximately 2 orders of magnitude) photocurrent densities under the same conditions, possibly because of their relatively less ordered crystallinity and the absence of rodlike morphologies. Because the synthetic protocol was identical in each case, we believe that these two distinct features reflect the environments in which these hematite photoanodes were formed. Consistent with the latest studies reported in the literature of the X-ray photoelectron spectra of fast-frozen hematite colloids in aqueous solutions, it appears that the degree of surface ion loading at the electrolyte-hematite interface (Stern layer) is critical during the development of hematite photoanodes. We suspect that a lower ion surface loading benefits the hematite developing relatively higher-order and a rodlike texture, thereby improving the photoelectrochemical activity.

  14. Elastic Coulomb breakup of 34Na

    NASA Astrophysics Data System (ADS)

    Singh, G.; Shubhchintak, Chatterjee, R.

    2016-08-01

    Background: 34Na is conjectured to play an important role in the production of seed nuclei in the alternate r -process paths involving light neutron rich nuclei very near the β -stability line, and as such, it is important to know its ground state properties and structure to calculate rates of the reactions it might be involved in, in the stellar plasma. Found in the region of `island of inversion', its ground state might not be in agreement with normal shell model predictions. Purpose: The aim of this paper is to study the elastic Coulomb breakup of 34Na on 208Pb to give us a core of 33Na with a neutron and in the process we try and investigate the one neutron separation energy and the ground state configuration of 34Na. Method: A fully quantum mechanical Coulomb breakup theory within the architecture of post-form finite range distorted wave Born approximation extended to include the effects of deformation is used to research the elastic Coulomb breakup of 34Na on 208Pb at 100 MeV/u. The triple differential cross section calculated for the breakup is integrated over the desired components to find the total cross-section, momentum, and angular distributions as well as the average momenta, along with the energy-angular distributions. Results: The total one neutron removal cross section is calculated to test the possible ground state configurations of 34Na. The average momentum results along with energy-angular calculations indicate 34Na to have a halo structure. The parallel momentum distributions with narrow full widths at half-maxima signify the same. Conclusion: We have attempted to analyze the possible ground state configurations of 34Na and in congruity with the patterns in the `island of inversion' conclude that even without deformation, 34Na should be a neutron halo with a predominant contribution to its ground state most probably coming from 33Na(3 /2+)⊗ 2 p3 /2ν configuration. We also surmise that it would certainly be useful and rewarding to test our

  15. Combined effects Na and SO2 in flue gas on Mn-Ce/TiO2 catalyst for low temperature selective catalytic reduction of NO by NH3 simulated by Na2SO4 doping

    NASA Astrophysics Data System (ADS)

    Zhou, Aiyi; Yu, Danqing; Yang, Liu; Sheng, Zhongyi

    2016-08-01

    A series of Mn-Ce/TiO2 catalysts were synthesized through an impregnation method and used for low temperature selective catalytic reduction (SCR) of NOx with ammonia (NH3). Na2SO4 was added into the catalyst to simulate the combined effects of alkali metal and SO2 in the flue gas. Experimental results showed that Na2SO4 had strong and fluctuant influence on the activity of Mn-Ce/TiO2, because the effect of Na2SO4 included pore occlusion and sulfation effect simultaneously. When Na2SO4 loading content increased from 0 to 1 wt.%, the SCR activities of Na2SO4-doped catalysts decreased greatly. With further increasing amount of Na2SO4, however, the catalytic activity increased gradually. XRD results showed that Na2SO4 doping could induce the crystallization of MnOx phases, which were also confirmed by TEM and SEM results. BET results showed that the surface areas decreased and a new bimodal mesoporous structure formed gradually with the increasing amount of Na2SO4. XPS results indicated that part of Ce4+ and Mn3+ were transferred to Ce3+ and Mn4+ due to the sulfation after Na2SO4 deposition on the surface of the catalysts. When the doped amounts of Na2SO4 increased, NH3-TPD results showed that the Lewis acid sites decreased and the Brønsted acid sites of Mn-Ce/TiO2 increased quickly, which could be considered as another reason for the observed changes in the catalytic activity. The decreased Mn and Ce atomic concentration, the changes of their oxidative states, and the variation in acidic properties on the surface of Na2SO4-doped catalysts could be the reasons for the fluctuant changes of the catalytic activity.

  16. SUGARLOAF ROADLESS AREA, CALIFORNIA.

    USGS Publications Warehouse

    Powell, Robert E.; Campbell, Harry W.

    1984-01-01

    On the basis of geologic, geochemical, and geophysical investigations and a survey of mines, quarries, and prospects the Sugarloaf Roadless Area, California, has little promise for the occurrence of metallic mineral or energy resources. Units of carbonate rock and graphitic schist have demonstrated resources of magnesian marble and graphite. Sand, gravel, and construction stone other than carbonate rock are present in the roadless area, but similar or better quality materials are abundant and more accessible outside the area.

  17. Protected area management

    USGS Publications Warehouse

    Fagre, Daniel B.; Prato, Tony; Wang, Yeqiao

    2014-01-01

    Designated protected areas are diverse in scope and purpose and have expanded from Yellowstone National Park in the United States, the world’s first national park, to 157,897 parks and protected areas distributed globally. Most are publicly owned and serve multiple needs that reflect regional or national cultures. With ever-increasing threats to the integrity of protected areas, managers are turning to flexible management practices such as scenario planning and adaptive management.

  18. SAVANNAH ROADLESS AREA, FLORIDA.

    USGS Publications Warehouse

    Patterson, Sam H.; Crandall, Thomas M.

    1984-01-01

    On the basis of a mineral survey the Savannah Roadless Area in Florida was appraised to offer little promise for the occurrence of mineral resources. The commodities identified in the area are deposits of sand and gravel; however, they are deeply buried, far from potential markets, and more readily accessible material exists outside the roadless area. The possibility that oil and gas might occur in the Jurassic Smackover Formation or in other formations at depth cannot be ruled out.

  19. Northwest Area Science

    USGS Publications Warehouse

    Fuentes, Tracy L.; van Heeswijk, Marijke; Grossman, Eric E.

    2010-01-01

    Northwest Area Facts * Population about 12 million * 43 federally recognized Tribes * Hydropower provides about two-thirds of electricity supply * 78 federally listed threatened and endangered species * 12 active or potentially active volcanoes * Columbia River system drains more than 260,000 square miles, an area about the size of Texas * More than 175 square miles covered by glaciers * More than 900 miles of Pacific Ocean coastline * More than 2,300 miles of greater Puget Sound coastline * Some forests store more carbon per unit area than any other area in the world, including the tropics * 51 percent federal lands * Significant lead, zinc, silver, and phosphate deposits

  20. Phoenix Lander Work Area

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image shows NASA's Phoenix Mars Lander Robotic Arm work area with an overlay. The pink area is available for digging, the green area is reserved for placing the Thermal and Electrical Conductivity Probe (TECP) instrument. Soil can be dumped in the violet area.

    Images were displayed using NASA Ames 'Viz' visualization software.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  1. Excess surface area in bioelectrochemical systems causes ion transport limitations

    PubMed Central

    Harrington, Timothy D.; Babauta, Jerome T.; Davenport, Emily K.; Renslow, Ryan S.; Beyenal, Haluk

    2014-01-01

    We investigated ion transport limitations on 3D graphite felt electrodes by growing Geobacter sulfurreducens biofilms with advection to eliminate external mass transfer limitations. We characterized ion transport limitations by: 1) showing that serially increasing NaCl concentration up to 200 mM increased current linearly up to a total of +273% vs. 0 mM NaCl under advective conditions, 2) growing the biofilm with a starting concentration of 200 mM NaCl, which led to a maximum current increase of 400% vs. current generation without NaCl, and 3) showing that un-colonized surface area remained even after steady-state current was reached. After accounting for iR effects, we confirmed that the excess surface area existed despite a non-zero overpotential at the electrode surface. The fact that the biofilm was constrained from colonizing and producing further current under these conditions confirmed the biofilms under study here were ion transport-limited. Our work demonstrates that the use of high surface area electrodes may not increase current density when the system design allows ion transport limitations to become dominant. PMID:25421463

  2. Excess surface area in bioelectrochemical systems causes ion transport limitations.

    PubMed

    Harrington, Timothy D; Babauta, Jerome T; Davenport, Emily K; Renslow, Ryan S; Beyenal, Haluk

    2015-05-01

    We investigated ion transport limitations on 3D graphite felt electrodes by growing Geobacter sulfurreducens biofilms with advection to eliminate external mass transfer limitations. We characterized ion transport limitations by: (i) showing that serially increasing NaCl concentration up to 200 mM increased current linearly up to a total of +273% vs. 0 mM NaCl under advective conditions; (ii) growing the biofilm with a starting concentration of 200 mM NaCl, which led to a maximum current increase of 400% vs. current generation without NaCl, and (iii) showing that un-colonized surface area remained even after steady-state current was reached. After accounting for iR effects, we confirmed that the excess surface area existed despite a non-zero overpotential. The fact that the biofilm was constrained from colonizing and producing further current under these conditions confirmed the biofilms under study here were ion transport-limited. Our work demonstrates that the use of high surface area electrodes may not increase current density when the system design allows ion transport limitations to become dominant. © 2014 Wiley Periodicals, Inc.

  3. Excess Surface Area in Bioelectrochemical Systems Causes ion Transport Limitations

    SciTech Connect

    Harrington, Timothy D.; Babauta, Jerome T.; Davenport, Emily K.; Renslow, Ryan S.; Beyenal, Haluk

    2015-05-01

    We investigated ion transport limitations on 3D graphite felt electrodes by growing Geobacter sulfurreducens biofilms with advection to eliminate external mass transfer limitations. We characterized ion transport limitations by: (i) showing that serially increasing NaCl concentration up to 200mM increased current linearly up to a total of þ273% vs. 0mM NaCl under advective conditions; (ii) growing the biofilm with a starting concentration of 200mM NaCl, which led to a maximum current increase of 400% vs. current generation without NaCl, and (iii) showing that un-colonized surface area remained even after steadystate current was reached. After accounting for iR effects, we confirmed that the excess surface area existed despite a non-zero overpotential. The fact that the biofilm was constrained from colonizing and producing further current under these conditions confirmed the biofilms under study here were ion transport-limited. Our work demonstrates that the use of high surface area electrodes may not increase current density when the system design allows ion transport limitations to become dominant.

  4. Quasi–solid state rechargeable Na-CO2 batteries with reduced graphene oxide Na anodes

    PubMed Central

    Hu, Xiaofei; Li, Zifan; Zhao, Yaran; Sun, Jianchao; Zhao, Qing; Wang, Jianbin; Tao, Zhanliang; Chen, Jun

    2017-01-01

    Na-CO2 batteries using earth-abundant Na and greenhouse gas CO2 are promising tools for mobile and stationary energy storage, but they still pose safety risks from leakage of liquid electrolyte and instability of the Na metal anode. These issues result in extremely harsh operating conditions of Na-CO2 batteries and increase the difficulty of scaling up this technology. We report the development of quasi–solid state Na-CO2 batteries with high safety using composite polymer electrolyte (CPE) and reduced graphene oxide (rGO) Na anodes. The CPE of PVDF-HFP [poly(vinylidene fluoride-co-hexafluoropropylene)]–4% SiO2/NaClO4–TEGDME (tetraethylene glycol dimethyl ether) has high ion conductivity (1.0 mS cm−1), robust toughness, a nonflammable matrix, and strong electrolyte-locking ability. In addition, the rGO-Na anode presents fast and nondendritic Na+ plating/stripping (5.7 to 16.5 mA cm−2). The improved kinetics and safety enable the constructed rGO-Na/CPE/CO2 batteries to successfully cycle in wide CO2 partial pressure window (5 to 100%, simulated car exhaust) and especially to run for 400 cycles at 500 mA g−1 with a fixed capacity of 1000 mA·hour g−1 in pure CO2. Furthermore, we scaled up the reversible capacity to 1.1 A·hour in pouch-type batteries (20 × 20 cm, 10 g, 232 Wh kg−1). This study makes quasi–solid state Na-CO2 batteries an attractive prospect. PMID:28164158

  5. Quasi-solid state rechargeable Na-CO2 batteries with reduced graphene oxide Na anodes.

    PubMed

    Hu, Xiaofei; Li, Zifan; Zhao, Yaran; Sun, Jianchao; Zhao, Qing; Wang, Jianbin; Tao, Zhanliang; Chen, Jun

    2017-02-01

    Na-CO2 batteries using earth-abundant Na and greenhouse gas CO2 are promising tools for mobile and stationary energy storage, but they still pose safety risks from leakage of liquid electrolyte and instability of the Na metal anode. These issues result in extremely harsh operating conditions of Na-CO2 batteries and increase the difficulty of scaling up this technology. We report the development of quasi-solid state Na-CO2 batteries with high safety using composite polymer electrolyte (CPE) and reduced graphene oxide (rGO) Na anodes. The CPE of PVDF-HFP [poly(vinylidene fluoride-co-hexafluoropropylene)]-4% SiO2/NaClO4-TEGDME (tetraethylene glycol dimethyl ether) has high ion conductivity (1.0 mS cm(-1)), robust toughness, a nonflammable matrix, and strong electrolyte-locking ability. In addition, the rGO-Na anode presents fast and nondendritic Na(+) plating/stripping (5.7 to 16.5 mA cm(-2)). The improved kinetics and safety enable the constructed rGO-Na/CPE/CO2 batteries to successfully cycle in wide CO2 partial pressure window (5 to 100%, simulated car exhaust) and especially to run for 400 cycles at 500 mA g(-1) with a fixed capacity of 1000 mA·hour g(-1) in pure CO2. Furthermore, we scaled up the reversible capacity to 1.1 A·hour in pouch-type batteries (20 × 20 cm, 10 g, 232 Wh kg(-1)). This study makes quasi-solid state Na-CO2 batteries an attractive prospect.

  6. Significant natural areas

    Treesearch

    C. I. Millar; M. G. Barbour; D. L. Elliott-Fisk; J. R. Shevock; W. B. Woolfenden

    1996-01-01

    The Sierra Nevada Ecosystem Project mapped 945 areas in the Sierra Nevada of ecological, cultural, and geological significance. Theseareas contain outstanding features of unusual rarity, diversity, andrepresentativeness on national forest and national park lands. Morethan 70% of the areas were newly recognized during the SNEP project. Local agency specialists familiar...

  7. Quadrilaterals: Diagonals and Area

    ERIC Educational Resources Information Center

    McGraw, Rebecca

    2017-01-01

    The task shared in this article provides geometry students with opportunities to recall and use basic geometry vocabulary, extend their knowledge of area relationships, and create area formulas. It is characterized by reasoning and sense making (NCTM 2009) and the "Construct viable arguments and critique the reasoning of others"…

  8. Study area description

    Treesearch

    Mary M. Rowland; Matthias Leu

    2011-01-01

    The boundary for the Wyoming Basins Ecoregional Assessment (WBEA) was largely determined by the co-occurrence of some of the largest tracts of intact sagebrush (Artemisia spp.) remaining in the western United States with areas of increasing resource extraction. The WBEA area includes two ecoregions in their entirety, Wyoming Basins and Utah-Wyoming...

  9. Cleaning Physical Education Areas.

    ERIC Educational Resources Information Center

    Griffin, William R.

    1999-01-01

    Discusses techniques to help create clean and inviting school locker rooms. Daily, weekly or monthly, biannual, and annual cleaning strategies for locker room showers are highlighted as are the specialized maintenance needs for aerobic and dance areas, running tracks, and weight training areas. (GR)

  10. Creative Outdoor Play Areas.

    ERIC Educational Resources Information Center

    Miller, Peggy L.

    Considering the creation of proper play areas for children (school sites, municipal and mini parks, private homes and backyards, shopping centers, apartment complexes, recreational areas, roadside parks, nursery schools, churches, summer camps, and drive-in theaters) as one of today's major challenges, the author recommends that professional…

  11. Outdoor Creative Play Areas.

    ERIC Educational Resources Information Center

    Miller, Peggy L.

    Guidelines are given for the development of outdoor play areas on school sites to provide children with natural areas and simple facilities for creative play. Site selection, analysis, and development are discussed. Natural, topographical features of the environment and natural play equipment are suggested. Illustrations are also presented to aid…

  12. Creative Outdoor Play Areas.

    ERIC Educational Resources Information Center

    Miller, Peggy L.

    Considering the creation of proper play areas for children (school sites, municipal and mini parks, private homes and backyards, shopping centers, apartment complexes, recreational areas, roadside parks, nursery schools, churches, summer camps, and drive-in theaters) as one of today's major challenges, the author recommends that professional…

  13. Broca's area - thalamic connectivity.

    PubMed

    Bohsali, Anastasia A; Triplett, William; Sudhyadhom, Atchar; Gullett, Joseph M; McGregor, Keith; FitzGerald, David B; Mareci, Thomas; White, Keith; Crosson, Bruce

    2015-02-01

    Broca's area is crucially involved in language processing. The sub-regions of Broca's area (pars triangularis, pars opercularis) presumably are connected via corticocortical pathways. However, growing evidence suggests that the thalamus may also be involved in language and share some of the linguistic functions supported by Broca's area. Functional connectivity is thought to be achieved via corticothalamic/thalamocortical white matter pathways. Our study investigates structural connectivity between Broca's area and the thalamus, specifically ventral anterior nucleus and pulvinar. We demonstrate that Broca's area shares direct connections with these thalamic nuclei and suggest a local Broca's area-thalamus network potentially involved in linguistic processing. Thalamic connectivity with Broca's area may serve to selectively recruit cortical regions storing multimodal features of lexical items and to bind them together during lexical-semantic processing. In addition, Broca's area-thalamic circuitry may enable cortico-thalamo-cortical information transfer and modulation between BA 44 and 45 during language comprehension and production. Published by Elsevier Inc.

  14. KSC Technology Area 8

    NASA Technical Reports Server (NTRS)

    Seibert, Marc A.

    2012-01-01

    Tracking, Timing, Communications and Navigation are critical to all NASA missions. Accurate weather prediction is critical to KSC launch activities. KSC is involved with and in several cases leading research and development in many exciting areas and with partners. We welcome new partners in all of these areas!

  15. Content Area Reading.

    ERIC Educational Resources Information Center

    French, Michael P., Ed.

    1985-01-01

    The theme for this focused journal issue is reading in the content areas. Articles discuss the following topics: (1) teaching reading strategies instead of skills; (2) teaching reading in elementary content areas; (3) metacognition and mapping; (4) a summer school program designed to appeal to poorly motivated junior high school students who are…

  16. Electrophysiological Determination of Submembrane Na(+) Concentration in Cardiac Myocytes.

    PubMed

    Hegyi, Bence; Bányász, Tamás; Shannon, Thomas R; Chen-Izu, Ye; Izu, Leighton T

    2016-09-20

    In the heart, Na(+) is a key modulator of the action potential, Ca(2+) homeostasis, energetics, and contractility. Because Na(+) currents and cotransport fluxes depend on the Na(+) concentration in the submembrane region, it is necessary to accurately estimate the submembrane Na(+) concentration ([Na(+)]sm). Current methods using Na(+)-sensitive fluorescent indicators or Na(+) -sensitive electrodes cannot measure [Na(+)]sm. However, electrophysiology methods are ideal for measuring [Na(+)]sm. In this article, we develop patch-clamp protocols and experimental conditions to determine the upper bound of [Na(+)]sm at the peak of action potential and its lower bound at the resting state. During the cardiac cycle, the value of [Na(+)]sm is constrained within these bounds. We conducted experiments in rabbit ventricular myocytes at body temperature and found that 1) at a low pacing frequency of 0.5 Hz, the upper and lower bounds converge at 9 mM, constraining the [Na(+)]sm value to ∼9 mM; 2) at 2 Hz pacing frequency, [Na(+)]sm is bounded between 9 mM at resting state and 11.5 mM; and 3) the cells can maintain [Na(+)]sm to the above values, despite changes in the pipette Na(+) concentration, showing autoregulation of Na(+) in beating cardiomyocytes.

  17. A new system of STRAW chambers operating in vacuum for the NA62 experiment

    NASA Astrophysics Data System (ADS)

    Potrebenikov, Yu

    2017-01-01

    Large 2.15 × 2.15 m2 area straw tube chambers have been developed to meet the specific requirements of the NA62 experiment. The main goal of the NA62 experiment at the CERN SPS is to measure the branching ratio of the ultra-rare decay with 10% accuracy. This can be achieved by detecting about 100 Standard Model events with 10% background in 2 - 3 years of data taking. A low mass tracking system is necessary to achieve a high resolution on kinematic quantities while timing resolution is mandatory to match the outgoing pion with the incoming kaon. Design, construction and first performance are reported.

  18. PYRAMID ROADLESS AREA, CALIFORNIA.

    USGS Publications Warehouse

    Armstrong, Augustus K.; Scott, Douglas F.

    1984-01-01

    A geologic and mineral survey was conducted in the Pyramid Roadless Area, California. The area contains mineral showings, but no mineral-resource potential was identified during our studies. Three granodiorite samples on the west side of the roadless area contained weakly anomalous concentrations of uranium. Two samples of roof-pendant rocks, one metasedimentary rock and one metavolcanic rock, contain low concentrations of copper, and of copper and molybdenum, respectively. Although none was identified, the geologic terrane is permissive for mineral occurrences and large-scale, detailed geologic mapping of the areas of metasedimentary and metavolcanic roof pendants in the Pyramid Roadless Area could define a mineral-resource potential for tungsten and precious metals.

  19. OLALLIE ROADLESS AREA, OREGON.

    USGS Publications Warehouse

    Walker, George W.; Neumann, Terry R.

    1984-01-01

    The Olallie Roadless Area, Oregon, is devoid of mines and mineral prospects, and a mineral-resource evaluation of the area did not identify any mineral-resource potential. There is no evidence that fossil fuels are present in the roadless area. Nearby areas in Clackamas, Marion, Jefferson, and Wasco Counties are characterized by higher-than-normal heat flow and by numerous thermal springs, some of which have been partly developed. this may indicate that the region has some, as yet undefined, potential for the development of geothermal energy. Lack of thermal springs or other evidence of localized geothermal anomalies within the roadless area may be the result of masking by young, nonconductive rock units and by the flooding out and dilution of rising thermal waters by cool meteoric water.

  20. Interaction of NaCl(g) and HCl(g) with condensed NA2SO4

    NASA Technical Reports Server (NTRS)

    Stearns, C. A.; Kohl, F. J.; Fryburg, G. C.; Miller, R. A.

    1977-01-01

    The interaction of Na2SO4(l) with NaCl(g), HCl(g) and H2O(g) was studied in atmospheric pressure flowing air and oxygen at Na2SO4(l) temperatures of 900 and 1000 C. Thermomicrogravimetric and high pressure mass spectrometric sampling techniques were used. Experimental results establish that previously reported enhanced rates of weight loss of Na2SO4(l) in the presence of NaCl(g) are due to the reaction: Na2SO4(c) + 2HCl(g) = 2NaCl(g) + SO2(g) + H2O(g) + 1/2O2(g) being driven to the right in flowing gas systems. The HCl(g) is the product of hydrolysis of NaCl caused by small but significant amounts of H2O(g) present in the system. Thermochemical calculations are used to show that even with sub-ppm levels of H2O(g) present, significant quantities of HCl(g) are produced.

  1. Dynamics of Na + in a single crystal of Naβ″Al 2O 3

    NASA Astrophysics Data System (ADS)

    Fanjat, N.; Lucazeau, G.; Bates, J.; Dianoux, A. J.

    1989-01-01

    A single crystal of Naβ″ Al 2O 3 has been used to measure quasi-elastic neutron scattering spectra at 227 and 377°C. Fitted data are presented with a new model and the results are compared to those obtained with NaβAl 2O 3.

  2. Voltage dependence of Na translocation by the Na/K pump.

    PubMed

    Nakao, M; Gadsby, D C

    During each complete reaction cycle, the Na/K pump transports three Na ions out across the cell membrane and two K ions in. The resulting net extrusion of positive charge generates outward membrane current but, until now, it was unclear how that net charge movement occurs. Reasonable possibilities included a single positive charge moving outwards during Na translocation; or a single negative charge moving inwards during K translocation; or either positive or negative charges moving during both translocation steps, but in unequal quantities. Any step that involves net charge movement through the membrane must have voltage-dependent transition rates. Here we report measurements of transient, voltage-dependent, displacement currents generated by the pump when its normal Na/K transport cycle has been interrupted by removal of external K and it is thus constrained to carry out Na/Na exchange. The quantity and voltage sensitivity of the charge moved during these transient currents suggests that Na translocation includes a voltage-dependent transition involving movement of one positive charge across the membrane. This single step can thus fully account for the electrogenic nature of Na/K exchange. The result provides important new insight into the molecular mechanism of active cation transport.

  3. Dynamics of Na(+)(Benzene) + Benzene Association and Ensuing Na(+)(Benzene)2* Dissociation.

    PubMed

    Paul, Amit K; Kolakkandy, Sujitha; Hase, William L

    2015-07-16

    Chemical dynamics simulations were used to study Bz + Na(+)(Bz) → Na(+)(Bz)2* association and the ensuing dissociation of the Na(+)(Bz)2* cluster (Bz = benzene). An interesting and unexpected reaction found from the simulations is direct displacement, for which the colliding Bz molecule displaces the Bz molecule attached to Na(+), forming Na(+)(Bz). The rate constant for Bz + Na(+)(Bz) association was calculated at 750 and 1000 K, and found to decrease with increase in temperature. By contrast, the direct displacement rate constant increases with temperature. The cross section and rate constant for direct displacement are approximately an order of magnitude lower than those for association. The Na(+)(Bz)2* cluster, formed by association, dissociates with a biexponential probability, with the rate constant for the short-time component approximately an order of magnitude larger than that for the longer time component. The latter rate constant agrees with that of Rice-Ramsperger-Kassel-Marcus (RRKM) theory, consistent with rapid intramolecular vibrational energy redistribution (IVR) and intrinsic RRKM dynamics for the Na(+)(Bz)2* cluster. A coupled phase space model was used to analyze the biexponential dissociation probability.

  4. Safety and immunogenicity of the Na-GST-1 hookworm vaccine in Brazilian and American adults

    PubMed Central

    Diemert, David J.; Freire, Janaína; Valente, Vanderson; Fraga, Carlos Geraldo; Talles, Frederico; Grahek, Shannon; Campbell, Doreen; Jariwala, Amar; Periago, Maria Victoria; Enk, Martin; Gazzinelli, Maria Flávia; Bottazzi, Maria Elena; Hamilton, Robert; Brelsford, Jill; Yakovleva, Anna; Li, Guangzhao; Peng, Jin; Correa-Oliveira, Rodrigo; Hotez, Peter; Bethony, Jeffrey

    2017-01-01

    Necator americanus Glutathione-S-Transferase-1 (Na-GST-1) plays a role in the digestion of host hemoglobin by adult N. americanus hookworms. Vaccination of laboratory animals with recombinant Na-GST-1 is associated with significant protection from challenge infection. Recombinant Na-GST-1 was expressed in Pichia pastoris and adsorbed to aluminum hydroxide adjuvant (Alhydrogel) according to current Good Manufacturing Practice. Two Phase 1 trials were conducted in 142 healthy adult volunteers in the United States and Brazil, first in hookworm-naïve individuals and then in residents of a N. americanus endemic area in Brazil. Volunteers received one of three doses of recombinant Na-GST-1 (10, 30, or 100 μg) adjuvanted with Alhydrogel, adjuvanted with Alhydrogel and co-administered with an aqueous formulation of Glucopyranosyl Lipid A (GLA-AF), or the hepatitis B vaccine. Vaccinations were administered via intramuscular injection on days 0, 56, and 112. Na-GST-1/Alhydrogel was well tolerated in both hookworm-naïve and hookworm-exposed adults, with the most common adverse events being mild to moderate injection site pain and tenderness, and mild headache and nausea; no vaccine-related severe or serious adverse events were observed. Antigen-specific IgG antibodies were induced in a dose-dependent fashion, with increasing levels observed after each vaccination in both trials. The addition of GLA-AF to Na-GST-1/Alhydrogel did not result in significant increases in specific IgG responses. In both the US and Brazil studies, the predominant IgG subclass induced against Na-GST-1 was IgG1, with lesser amounts of IgG3. Vaccination of both hookworm-naïve and hookworm-exposed adults with recombinant Na-GST-1 was safe, well tolerated, and resulted in significant antigen-specific IgG responses. Based on these results, this vaccine will be advanced into clinical trials in children and eventual efficacy studies. Trial registration ClinicalTrials.gov (NCT01261130 for the Brazil

  5. Low-affinity Na+ uptake in the halophyte Suaeda maritima.

    PubMed

    Wang, Suo-Min; Zhang, Jin-Lin; Flowers, Timothy J

    2007-10-01

    Na(+) uptake by plant roots has largely been explored using species that accumulate little Na(+) into their shoots. By way of contrast, the halophyte Suaeda maritima accumulates, without injury, concentrations of the order of 400 mM NaCl in its leaves. Here we report that cAMP and Ca(2+) (blockers of nonselective cation channels) and Li(+) (a competitive inhibitor of Na(+) uptake) did not have any significant effect on the uptake of Na(+) by the halophyte S. maritima when plants were in 25 or 150 mM NaCl (150 mM NaCl is near optimal for growth). However, the inhibitors of K(+) channels, TEA(+) (10 mM), Cs(+) (3 mM), and Ba(2+) (5 mM), significantly reduced the net uptake of Na(+) from 150 mM NaCl over 48 h, by 54%, 24%, and 29%, respectively. TEA(+) (10 mM), Cs(+) (3 mM), and Ba(2+) (1 mm) also significantly reduced (22)Na(+) influx (measured over 2 min in 150 mM external NaCl) by 47%, 30%, and 31%, respectively. In contrast to the situation in 150 mm NaCl, neither TEA(+) (1-10 mM) nor Cs(+) (0.5-10 mM) significantly reduced net Na(+) uptake or (22)Na(+) influx in 25 mM NaCl. Ba(2+) (at 5 mm) did significantly decrease net Na(+) uptake (by 47%) and (22)Na(+) influx (by 36% with 1 mM Ba(2+)) in 25 mM NaCl. K(+) (10 or 50 mM) had no effect on (22)Na(+) influx at concentrations below 75 mM NaCl, but the influx of (22)Na(+) was inhibited by 50 mM K(+) when the external concentration of NaCl was above 75 mM. The data suggest that neither nonselective cation channels nor a low-affinity cation transporter are major pathways for Na(+) entry into root cells. We propose that two distinct low-affinity Na(+) uptake pathways exist in S. maritima: Pathway 1 is insensitive to TEA(+) or Cs(+), but sensitive to Ba(2+) and mediates Na(+) uptake under low salinities (25 mM NaCl); pathway 2 is sensitive to TEA(+), Cs(+), and Ba(2+) and mediates Na(+) uptake under higher external salt concentrations (150 mM NaCl). Pathway 1 might be mediated by a high-affinity K transporter

  6. Anion-coupled Na efflux mediated by the human red blood cell Na/K pump

    SciTech Connect

    Dissing, S.; Hoffman, J.F. )

    1990-07-01

    The red cell Na/K pump is known to continue to extrude Na when both Na and K are removed from the external medium. Because this ouabain-sensitive flux occurs in the absence of an exchangeable cation, it is referred to as uncoupled Na efflux. This flux is also known to be inhibited by 5 mM Nao but to a lesser extent than that inhibitable by ouabain. Uncoupled Na efflux via the Na/K pump therefore can be divided into a Nao-sensitive and Nao-insensitive component. We used DIDS-treated, SO4-equilibrated human red blood cells suspended in HEPES-buffered (pHo 7.4) MgSO4 or (Tris)2SO4, in which we measured 22Na efflux, 35SO4 efflux, and changes in the membrane potential with the fluorescent dye, diS-C3 (5). A principal finding is that uncoupled Na efflux occurs electroneurally, in contrast to the pump's normal electrogenic operation when exchanging Nai for Ko. This electroneutral uncoupled efflux of Na was found to be balanced by an efflux of cellular anions. (We were unable to detect any ouabain-sensitive uptake of protons, measured in an unbuffered medium at pH 7.4 with a Radiometer pH-STAT.) The Nao-sensitive efflux of Nai was found to be 1.95 +/- 0.10 times the Nao-sensitive efflux of (SO4)i, indicating that the stoichiometry of this cotransport is two Na+ per SO4=, accounting for 60-80% of the electroneutral Na efflux. The remainder portion, that is, the ouabain-sensitive Nao-insensitive component, has been identified as PO4-coupled Na transport and is the subject of a separate paper. That uncoupled Na efflux occurs as a cotransport with anions is supported by the result, obtained with resealed ghosts, that when internal and external SO4 was substituted by the impermeant anion, tartrate i,o, the efflux of Na was inhibited 60-80%. This inhibition could be relieved by the inclusion, before DIDS treatment, of 5 mM Cli,o.

  7. A thermochemical explanation for the stability of NaCl3 and NaCl7

    NASA Astrophysics Data System (ADS)

    Fernandes de Farias, Robson

    2017-03-01

    Thermodynamically stable cubic and orthorhombic NaCl3 as well as NaCl7 have been synthesized (Zhang et al., 2013). In the present work, a thermochemical explanation for the stability of such unusual sodium chlorides is provided, based on lattice energy values. Using the Glasser-Jenkins generalized equation (Glasser and Jenkins, 2000) lattice energies (kJ mol-1) of -162.5, -168.9 and -113.1 are calculated for Pm3n NaCl3, Pnma NaCl3 and NaCl7, respectively. It is postulated that any NaxCly compound could be synthesized, if the ionic character of the Nasbnd Cl bond in the prepared compound remains around 80%, and the sodium charge below unit.

  8. Na-ion dynamics in Quasi-1D compound NaV2O4

    NASA Astrophysics Data System (ADS)

    Månsson, M.; Umegaki, I.; Nozaki, H.; Higuchi, Y.; Kawasaki, I.; Watanabe, I.; Sakurai, H.; Sugiyama, J.

    2014-12-01

    We have used the pulsed muon source at ISIS to study high-temperature Na-ion dynamics in the quasi-one-dimensional (Q1D) metallic antiferromagnet NaV2O4. By performing systematic zero-field and longitudinal-field measurements as a function of temperature we clearly distinguish that the hopping rate increases exponentially above Tdiff ≈ 250 K. The data is well fitted to an Arrhenius type equation typical for a diffusion process, showing that the Na-ions starts to be mobile above Tdiff. Such results make this compound very interesting for the tuning of Q1D magnetism using atomic-scale ion-texturing through the periodic potential from ordered Na-vacancies. Further, it also opens the door to possible use of NaV2O4 and related compounds in energy related applications.

  9. EDITORIAL: TaCoNa-Photonics 2008 TaCoNa-Photonics 2008

    NASA Astrophysics Data System (ADS)

    Chigrin, Dmitry N.; Busch, Kurt; Lavrinenko, Andrei V.

    2009-11-01

    This special section on theoretical and computational nano-photonics features papers presented at the first International Workshop on Theoretical and Computational Nano-Photonics (TaCoNa-Photonics 2008) held in Bad Honnef, Germany, 3-5 December 2008. The workshop covered a broad range of topics related to current developments and achievements in this interdisciplinary area of research. Since the late 1960s, the word `photonics' has been understood as the science of generating, controlling, and detecting light. Nowadays, a routine fabrication of complex structures with micro- and nano-scale dimensions opens up many new and exciting possibilities in photonics. The science of generating, routing and detecting light in micro- and nano-structured matter, `nano-photonics', is becoming more important both in research and technology and offers many promising applications. The inherently sub-wavelength character of the structures that nano-photonics deals with challenges modern theoretical and computational physics and engineering with many nontrivial questions: Up to what length-scale can one use a macroscopic phenomenological description of matter? Where is the interface between the classical and quantum description of light in nano-scale structures? How can one combine different physical systems, different time- and length-scales in a single computational model? How can one engineer nano-structured materials in order to achieve the desired optical properties for particular applications? Any attempt at answering these kinds of questions is impossible without the joint efforts of physicists, engineers, applied mathematicians and programmers. This is the reason why the major goal of the TaCoNa-Photonics workshops is to provide a forum where theoreticians and specialists in numerical methods from all branches of physics, engineering sciences and mathematics can compare their results, report on novel results and breakthroughs, and discuss new challenges ahead. In order to

  10. Na/K pump inactivation, subsarcolemmal Na measurements, and cytoplasmic ion turnover kinetics contradict restricted Na spaces in murine cardiac myocytes.

    PubMed

    Lu, Fang-Min; Hilgemann, Donald W

    2017-07-03

    Decades ago, it was proposed that Na transport in cardiac myocytes is modulated by large changes in cytoplasmic Na concentration within restricted subsarcolemmal spaces. Here, we probe this hypothesis for Na/K pumps by generating constitutive transsarcolemmal Na flux with the Na channel opener veratridine in whole-cell patch-clamp recordings. Using 25 mM Na in the patch pipette, pump currents decay strongly during continuous activation by extracellular K (τ, ∼2 s). In contradiction to depletion hypotheses, the decay becomes stronger when pump currents are decreased by hyperpolarization. Na channel currents are nearly unchanged by pump activity in these conditions, and conversely, continuous Na currents up to 0.5 nA in magnitude have negligible effects on pump currents. These outcomes are even more pronounced using 50 mM Li as a cytoplasmic Na congener. Thus, the Na/K pump current decay reflects mostly an inactivation mechanism that immobilizes Na/K pump charge movements, not cytoplasmic Na depletion. When channel currents are increased beyond 1 nA, models with unrestricted subsarcolemmal diffusion accurately predict current decay (τ ∼15 s) and reversal potential shifts observed for Na, Li, and K currents through Na channels opened by veratridine, as well as for Na, K, Cs, Li, and Cl currents recorded in nystatin-permeabilized myocytes. Ion concentrations in the pipette tip (i.e., access conductance) track without appreciable delay the current changes caused by sarcolemmal ion flux. Importantly, cytoplasmic mixing volumes, calculated from current decay kinetics, increase and decrease as expected with osmolarity changes (τ >30 s). Na/K pump current run-down over 20 min reflects a failure of pumps to recover from inactivation. Simulations reveal that pump inactivation coupled with Na-activated recovery enhances the rapidity and effectivity of Na homeostasis in cardiac myocytes. In conclusion, an autoregulatory mechanism enhances cardiac Na/K pump activity when

  11. Functional coupling of renal K+ and Na+ handling causes high blood pressure in Na+ replete mice.

    PubMed

    Vitzthum, Helga; Seniuk, Anika; Schulte, Laura Helene; Müller, Maxie Luise; Hetz, Hannah; Ehmke, Heimo

    2014-03-01

    A network of kinases, including WNKs, SPAK and Sgk1, is critical for the independent regulation of K+ and Na+ transport in the distal nephron. Angiotensin II is thought to act as a key hormone in orchestrating these kinases to switch from K+ secretion during hyperkalaemia to Na+ reabsorption during intravascular volume depletion, thus keeping disturbances in electrolyte and blood pressure homeostasis at a minimum. It remains unclear, however, how K+ and Na+ transport are regulated during a high Na+ intake, which is associated with suppressed angiotensin II levels and a high distal tubular Na+ load. We therefore investigated the integrated blood pressure, renal, hormonal and gene and protein expression responses to large changes of K+ intake in Na+ replete mice. Both low and high K+ intake increased blood pressure and caused Na+ retention. Low K+ intake was accompanied by an upregulation of the sodium-chloride cotransporter (NCC) and its activating kinase SPAK, and inhibition of NCC normalized blood pressure. Renal responses were unaffected by angiotensin AT1 receptor antagonism, indicating that low K+ intake activates the distal nephron by an angiotensin-independent mode of action. High K+ intake was associated with elevated plasma aldosterone concentrations and an upregulation of the epithelial sodium channel (ENaC) and its activating kinase Sgk1. Surprisingly, high K+ intake increased blood pressure even during ENaC or mineralocorticoid receptor antagonism, suggesting the contribution of aldosterone-independent mechanisms. These findings show that in a Na+ replete state, changes in K+ intake induce specific molecular and functional adaptations in the distal nephron that cause a functional coupling of renal K+ and Na+ handling, resulting in Na+ retention and high blood pressure when K+ intake is either restricted or excessively increased.

  12. Changes in Intracellular Na+ following Enhancement of Late Na+ Current in Virtual Human Ventricular Myocytes

    PubMed Central

    Giles, Wayne R.

    2016-01-01

    The slowly inactivating or late Na+ current, INa-L, can contribute to the initiation of both atrial and ventricular rhythm disturbances in the human heart. However, the cellular and molecular mechanisms that underlie these pro-arrhythmic influences are not fully understood. At present, the major working hypothesis is that the Na+ influx corresponding to INa-L significantly increases intracellular Na+, [Na+]i; and the resulting reduction in the electrochemical driving force for Na+ reduces and (may reverse) Na+/Ca2+ exchange. These changes increase intracellular Ca2+, [Ca2+]i; which may further enhance INa-L due to calmodulin-dependent phosphorylation of the Na+ channels. This paper is based on mathematical simulations using the O’Hara et al (2011) model of baseline or healthy human ventricular action potential waveforms(s) and its [Ca2+]i homeostasis mechanisms. Somewhat surprisingly, our results reveal only very small changes (≤ 1.5 mM) in [Na+]i even when INa-L is increased 5-fold and steady-state stimulation rate is approximately 2 times the normal human heart rate (i.e. 2 Hz). Previous work done using well-established models of the rabbit and human ventricular action potential in heart failure settings also reported little or no change in [Na+]i when INa-L was increased. Based on our simulations, the major short-term effect of markedly augmenting INa-L is a significant prolongation of the action potential and an associated increase in the likelihood of reactivation of the L-type Ca2+ current, ICa-L. Furthermore, this action potential prolongation does not contribute to [Na+]i increase. PMID:27875582

  13. Changes in Intracellular Na+ following Enhancement of Late Na+ Current in Virtual Human Ventricular Myocytes.

    PubMed

    Cardona, Karen; Trenor, Beatriz; Giles, Wayne R

    2016-01-01

    The slowly inactivating or late Na+ current, INa-L, can contribute to the initiation of both atrial and ventricular rhythm disturbances in the human heart. However, the cellular and molecular mechanisms that underlie these pro-arrhythmic influences are not fully understood. At present, the major working hypothesis is that the Na+ influx corresponding to INa-L significantly increases intracellular Na+, [Na+]i; and the resulting reduction in the electrochemical driving force for Na+ reduces and (may reverse) Na+/Ca2+ exchange. These changes increase intracellular Ca2+, [Ca2+]i; which may further enhance INa-L due to calmodulin-dependent phosphorylation of the Na+ channels. This paper is based on mathematical simulations using the O'Hara et al (2011) model of baseline or healthy human ventricular action potential waveforms(s) and its [Ca2+]i homeostasis mechanisms. Somewhat surprisingly, our results reveal only very small changes (≤ 1.5 mM) in [Na+]i even when INa-L is increased 5-fold and steady-state stimulation rate is approximately 2 times the normal human heart rate (i.e. 2 Hz). Previous work done using well-established models of the rabbit and human ventricular action potential in heart failure settings also reported little or no change in [Na+]i when INa-L was increased. Based on our simulations, the major short-term effect of markedly augmenting INa-L is a significant prolongation of the action potential and an associated increase in the likelihood of reactivation of the L-type Ca2+ current, ICa-L. Furthermore, this action potential prolongation does not contribute to [Na+]i increase.

  14. Recent results from MoNA-LISA

    NASA Astrophysics Data System (ADS)

    Spyrou, Artemisia

    2012-03-01

    Studies of the nuclear properties of nuclei close and even beyond the limits of stability have revealed exotic modes of decay and new structural characteristics. The MoNA-LISA array is used at the National Superconducting Cyclotron Laboratory at Michigan State University to study nuclei along the neutron dripline. In a typical experiment, a radioactive beam is employed to produce the neutron-unbound state of interest. This state/resonance immediately decay into a neutron, which is detected by MoNA-LISA and a remaining charged nucleus detected by the sweeper magnet detector suite. In this talk, new exciting findings from recent MoNA-LISA experiments will be presented. These include the first observation of a dineutron decay from ^16Be, the exploration of the ``south shore'' of the Island of Inversion and the first evidence of the decay of the troubling nucleus ^26O.

  15. Photoionization studies of Na/sub 2/Cl and Na/sub 2/O and reactions of metal clusters

    SciTech Connect

    Peterson, K.I.; Dao, P.D.; Castleman, A.W. Jr.

    1983-07-15

    Reaction between metal clusters and various reactant gases in a coexpanding nozzle led to the formation of Na/sub 2/Cl and Na/sub 2/O. These species were subjected to photoionization using a UV light source, monochromator, and mass spectrometer detection system. Appearance potentials of 95.7 and 116.7 kcal/mol were obtained for Na/sub 2/Cl and Na/sub 2/O, respectively. The appearance potential of the Na/sub 2/Cl lies between the ionization potential of the metal and the electron affinity of chlorine, while that of Na/sub 2/O is close to the ionization potential of the metal. Using these values and other literature data, energies were derived for the following bonds: Na--NaCl (19.7 kcal/mol), Na/sup +//sub 2/xCl (115.5), Na/sub 2/xCl (98.9), and Na/sup +//sub 2/xCl/sup -/ (127.8); Na/sup +/xNaO (56.8), Na/sup +//sub 2/xO (94.2), Na/sub 2/xO (98.6), and Na/sup +//sub 2/xO/sup -/ (177.2).

  16. Protected areas and poverty

    PubMed Central

    Brockington, Daniel; Wilkie, David

    2015-01-01

    Protected areas are controversial because they are so important for conservation and because they distribute fortune and misfortune unevenly. The nature of that distribution, as well as the terrain of protected areas themselves, have been vigorously contested. In particular, the relationship between protected areas and poverty is a long-running debate in academic and policy circles. We review the origins of this debate and chart its key moments. We then outline the continuing flashpoints and ways in which further evaluation studies could improve the evidence base for policy-making and conservation practice. PMID:26460124

  17. The Harz Foehn Area,

    DTIC Science & Technology

    1981-09-08

    AD-AI05 602 FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AF8 OH F/S 4/2 THE HARZ FOEHN AREA,(U) SEP 81 8 H NTS HEL UNCLASSIFIED FTD-IDIRS)T!0859-81 NLI I...7- 1981.3 THE HARZ FOEHN AREA E by Gerhard Hentsche. Approved for public release; distribution unlimited. U8 FTD-ID (RS)T-0859-81 EDITED TRANSLATION...DIVISION VISION. WP.AFB. OHIO. FTD-ID(RS)T-0859-81 Date 8 Sep 9 81 f 0 THE HARZ FOEHN AREA Gerhard Hentscheo i THE ARZ OEHNARE 1d A. INTRODUCTION I

  18. Protected areas and poverty.

    PubMed

    Brockington, Daniel; Wilkie, David

    2015-11-05

    Protected areas are controversial because they are so important for conservation and because they distribute fortune and misfortune unevenly. The nature of that distribution, as well as the terrain of protected areas themselves, have been vigorously contested. In particular, the relationship between protected areas and poverty is a long-running debate in academic and policy circles. We review the origins of this debate and chart its key moments. We then outline the continuing flashpoints and ways in which further evaluation studies could improve the evidence base for policy-making and conservation practice.

  19. RUBICON ROADLESS AREA, CALIFORNIA.

    USGS Publications Warehouse

    Harwood, David S.; Cather, Eric E.

    1984-01-01

    The Rubicon Roadless Area encompasses about 8 sq mi along the lower reaches of the Rubicon River, a major tributary of the Middle Fork of the American River that drains the west slope of the Sierra Nevada in eastern California. Based on mineral-resource surveys the area has little promise for the occurrence of metallic or energy resources. A very small demonstrated gold resource occurs at the Pigeon Roost mine. Glacial deposits, which occur in the eastern part of the area, are too bouldery and too small to be of value as construction materials.

  20. Targeting voltage gated sodium channels NaV1.7, Na V1.8, and Na V1.9 for treatment of pathological cough.

    PubMed

    Muroi, Yukiko; Undem, Bradley J

    2014-02-01

    Recent advances in our understanding of voltage-gated sodium channels (NaVs) lead to the rational hypothesis that drugs capable of selective blockade of NaV subtypes may be a safe and effective strategy for the treatment of unwanted cough. Among the nine NaV subtypes (NaV1.1-NaV1.9), the afferent nerves involved in initiating cough, in common with nociceptive neurons in the somatosensory system, express mainly NaV1.7, NaV1.8, and NaV1.9. Although knowledge about the effect of selectively blocking these channels on the cough reflex is limited, their biophysical properties indicate that each may contribute to the hypertussive and allotussive state that typifies subacute and chronic nonproductive cough.

  1. Intracellular [Na+], Na+ pathways, and fluid transport in cultured bovine corneal endothelial cells.

    PubMed

    Kuang, Kunyan; Li, Yansui; Yiming, Maimaiti; Sánchez, José M; Iserovich, Pavel; Cragoe, E J; Diecke, Friedrich P J; Fischbarg, Jorge

    2004-07-01

    The mechanism of fluid transport across corneal endothelium remains unclear. We examine here the relative contributions of cellular mechanisms of Na+ transport and the homeostasis of intracellular [Na+] in cultured bovine corneal endothelial cells, and the influence of ambient Na+ and HCO3- on the deturgescence of rabbit cornea. Bovine corneal endothelial cells plated on glass coverslips were incubated for 60 min with 10 microm of the fluorescent Na+ indicator SBFI precursor in HCO3- HEPES (BH) Ringer's solution. After loading, cells were placed in a perfusion chamber. Indicator fluorescence (490 nm) was determined with a Chance-Legallais time-sharing fluorometer. Its voltage output was the ratio of the emissions excited at 340 and 380 nm. For calibration, cells were treated with gramicidin D. For fluid transport measurements, rabbit corneas were mounted in a Dikstein-Maurice chamber, and stromal thickness was measured with a specular microscope. The steady-state [Na+]i in BH was 14.36+/-0.38 mM (n = mean+/-s.e.). Upon exposure to Na+ -free BH solution (choline substituted), [Na+]i decreased to 1.81+/-0.20mM (n = 19). When going from Na+ -free plus 100 microm ouabain to BH plus ouabain, [Na+]i increased to 46.17+/-2.50 (n = 6) with a half time of 1.26+/-0.04 min; if 0.1 microm phenamil plus ouabain were present, it reached only 21.78+/-1.50mm. The exponential time constants (min-1) were: 0.56+/-0.04 for the Na+ pump; 0.39+/-0.01 for the phenamil sensitive Na+ channel; and 0.17+/-0.02 for the ouabain-phenamil-insensitive pathways. In HCO3- free medium (gluconate substituted), [Na+]i was 14.03+/-0.11mM; upon changing to BH medium, it increased to 30.77+/-0.74 mm. This last [Na+]i increase was inhibited 66% by 100 microm DIDS. Using BH medium, corneal thickness remained nearly constant, increasing at a rate of only 2.9+/-0.9 microm hr-1 during 3 hr. However, stromal thickness increased drastically (swelling rate 36.1+/-2.6 microm hr-1) in corneas superfused with BH

  2. Concentration dependence of Li+/Na+ diffusion in manganese hexacyanoferrates

    NASA Astrophysics Data System (ADS)

    Takachi, Masamitsu; Fukuzumi, Yuya; Moritomo, Yutaka

    2016-06-01

    Manganese hexacyanoferrates (Mn-HCFs) with a jungle-gym-type structure are promising cathode materials for Li+/Na+ secondary batteries (LIBs/SIBs). Here, we investigated the diffusion constants D Li/D Na of Li+/Na+ against the Li+/Na+ concentration x Na/x Li and temperature (T) of A 1.32Mn[Fe(CN)6]0.833.6H2O (A = Li and Na). We evaluated the activation energy E\\text{a}\\text{Li}/E\\text{a}\\text{Na} of D Li/D Na against x Na/x Li. We found that E\\text{a}\\text{Na} steeply increases with x Na from 0.41 eV at x Na = 0.69 to 0.7 eV at 1.1. The increase in E\\text{a}\\text{Na} is ascribed to the occupancy effect of the Na+ site. The increase in E\\text{a}\\text{Li} is suppressed, probably because the number of Li+ sites is three times that of Na+ sites.

  3. Na+/K+-ATPase: Activity and inhibition

    NASA Astrophysics Data System (ADS)

    Čolović, M.; Krstić, D.; Krinulović, K.; Momić, T.; Savić, J.; Vujačić, A.; Vasić, V.

    2009-09-01

    The aim of the study was to give an overview of the mechanism of inhibition of Na+/K+-ATPase activity induced by some specific and non specific inhibitors. For this purpose, the effects of some ouabain like compounds (digoxin, gitoxin), noble metals complexes ([PtCl2DMSO2], [AuCl4]-, [PdCl4]2-, [PdCl(dien)]+, [PdCl(Me4dien)]+), transition metal ions (Cu2+, Zn2+, Fe2+, Co2+), and heavy metal ions (Hg2+, Pb2+, Cd2+) on the activity of Na+/K+-ATPase from rat synaptic plasma membranes (SPM), porcine cerebral cortex and human erythrocytes were discussed.

  4. CAPE-2 Cubesat - ELaNa IV

    NASA Image and Video Library

    2016-07-25

    CAPE-2: Cajun Advanced Picosatellite Experiment – ELaNa IV CAPE-2 was developed by students from the University of Louisiana Lafayette to engage, inspire and educate K-12 students to encourage them to pursue STEM careers. The secondary focus is the technology demonstration of deployed solar panels to support the following payloads: text to speech, voice repeater, tweeting, email, file transfer and data collection from buoys. Launched by NASA’s CubeSat Launch Initiative on the ELaNa IV mission as an auxiliary payload aboard the U.S. Air Force-led Operationally Responsive Space (ORS-3) Mission on November 19, 2013.

  5. Sodium-difluoro(oxalato)borate (NaDFOB): a new electrolyte salt for Na-ion batteries.

    PubMed

    Chen, Juner; Huang, Zhenguo; Wang, Caiyun; Porter, Spencer; Wang, Baofeng; Lie, Wilford; Liu, Hua Kun

    2015-06-18

    A new electrolyte salt, sodium-difluoro(oxalato)borate (NaDFOB), was synthesized and studied, which enables excellent reversible capacity and high rate capability when used in Na/Na0.44MnO2 half cells. NaDFOB has excellent compatibility with various common solvents used in Na-ion batteries, in strong contrast to the solvent dependent performances of NaClO4 and NaPF6. In addition, NaDFOB possesses good stability and generates no toxic or dangerous products when exposed to air and water. All these properties demonstrate that NaDFOB could be used to prepare high performance electrolytes for emerging Na-ion batteries.

  6. Urban Greening Bay Area

    EPA Pesticide Factsheets

    Information about the San Francisco Bay Water Quality Project (SFBWQP) Urban Greening Bay Area, a large-scale effort to re-envision urban landscapes to include green infrastructure (GI) making communities more livable and reducing stormwater runoff.

  7. Decontamination & decommissioning focus area

    SciTech Connect

    1996-08-01

    In January 1994, the US Department of Energy Office of Environmental Management (DOE EM) formally introduced its new approach to managing DOE`s environmental research and technology development activities. The goal of the new approach is to conduct research and development in critical areas of interest to DOE, utilizing the best talent in the Department and in the national science community. To facilitate this solutions-oriented approach, the Office of Science and Technology (EM-50, formerly the Office of Technology Development) formed five Focus AReas to stimulate the required basic research, development, and demonstration efforts to seek new, innovative cleanup methods. In February 1995, EM-50 selected the DOE Morgantown Energy Technology Center (METC) to lead implementation of one of these Focus Areas: the Decontamination and Decommissioning (D & D) Focus Area.

  8. Investigating Curiosity Drill Area

    NASA Image and Video Library

    2013-02-09

    NASA Mars rover Curiosity used its Mast Camera Mastcam to take the images combined into this mosaic of the drill area, called John Klein, where the rover ultimately performed its first sample drilling.

  9. Acquisitions for Area Programs

    ERIC Educational Resources Information Center

    Stevens, Robert D.

    1970-01-01

    Common policies, practices, and trends in acquisitions in the complex field of area studies, including the weak structure of the book trade, the lack of bibliographic control, and current cooperative efforts. (JS)

  10. Student Commons Areas.

    ERIC Educational Resources Information Center

    Owens, Rhonda

    2001-01-01

    Explores the new philosophy, lighting arrangements, and planning considerations behind the next generation of school common area design. Designs that enhance safety and security, and that can be flexible for other school functions are also discussed. (GR)

  11. Phoenix Work Area Animation

    NASA Image and Video Library

    2008-05-28

    This image from Sol 1 shows a mosaic of NASA Mars Phoenix digging area in the Martian terrain. Phoenix scientists were very pleased with this view as the terrain features few rocks -- an optimal place for digging.

  12. 300 AREA URANIUM CONTAMINATION

    SciTech Connect

    BORGHESE JV

    2009-07-02

    {sm_bullet} Uranium fuel production {sm_bullet} Test reactor and separations experiments {sm_bullet} Animal and radiobiology experiments conducted at the. 331 Laboratory Complex {sm_bullet} .Deactivation, decontamination, decommissioning,. and demolition of 300 Area facilities

  13. Uncratered Area on Mercury

    NASA Image and Video Library

    1999-10-08

    A dark, smooth, relatively uncratered area on Mercury was photographed two hours after NASA Mariner 10 flew by the planet. The prominent, sharp crater with a central peak is 30 kilometers 19 miles across.

  14. Naïve averaged, naïve pooled, and population pharmacokinetics of orally administered marbofloxacin in juvenile harbor seals.

    PubMed

    KuKanich, Butch; Huff, David; Riviere, Jim E; Papich, Mark G

    2007-02-01

    To determine the pharmacokinetics of marbofloxacin after oral administration in juvenile harbor seals (Phoca vitulina) at a dose of 5 mg/kg (2.3 mg/lb) and to compare pharmacokinetic variables after pharmacokinetic analysis by naïve averaged, naïve pooled, and nonlinear mixed-effects modeling. Original study. Animals-33 male and 22 female juvenile seals being treated for various conditions. Blood collection was limited to < or = 3 samples/seal. Plasma marbofloxacin concentrations were measured via high-pressure liquid chromatography with UV detection. Mean +/- SE dose of marbofloxacin administered was 5.3 +/- 0.1 mg/kg (2.4 +/- 0.05 mg/lb). The terminal half-life, volume of distribution (per bioavailability), and clearance (per bioavailability) were approximately 5 hours, approximately 1.4 L/kg, and approximately 3 mL/min/kg, respectively (values varied slightly with the method of calculation). Maximum plasma concentration and area under the plasma-time concentration curve were approximately 3 microg/mL and 30 h x microg/mL, respectively. Naïve averaged and naïve pooled analysis appeared to yield a better fit to the population, but nonlinear mixed-effects modeling yielded a better fit for individual seals. Values of pharmacokinetic variables were similar regardless of the analytic method used. Pharmacokinetic variability can be assessed with nonlinear mixed-effects modeling, but not with naïve averaged or naïve pooled analysis. Visual observation by experienced trainers revealed no adverse effects in treated seals. Plasma concentrations attained with a dosage of 5 mg/kg every 24 hours would be expected to be efficacious for treatment of infections caused by susceptible bacteria (excluding Pseudomonas aeruginosa).

  15. Neutralization of Hydroxide Ion in Melt-Grown NaCl Crystals

    NASA Technical Reports Server (NTRS)

    Otterson, Dumas A.

    1961-01-01

    Many recent studies of solid-state phenomena, particularly in the area of crystal imperfections, have involved the use of melt-grown NaCl single crystals. Quite often trace impurities in these materials have had a prominent effect on these phenomena. Trace amounts of hydroxide ion have been found in melt-grown NaCl crystals. This paper describes a nondestructive method of neutralizing the hydroxide ion in such crystals. Crystals of similar hydroxide content are maintained at an elevated temperature below the melting point of NaCl in a flowing atmosphere containing. dry hydrogen chloride. Heat treatment is continued until an analysis of the test specimens shows no excess hydroxide ion. A colorimetric method previously described4 is used for this analysis.

  16. RISC mezzanines for controlling data acquisition in the NA48 experiment at CERN

    NASA Astrophysics Data System (ADS)

    Guzik, Z.; Chlopik, A.; Bal, Fr.; Formenti, F.; Lacourt, A.

    2000-09-01

    A part of the LKr calorimeter data acquisition system of the NA48 experiment (a precision measurements of ɛ/ɛ' in CP violating; K 0→2π decays) is described. The experiment runs on the SPS north area in CERN. This paper presents some aspects of controlling the NA48 readout process based on commercial RIO 8260 RISC processors, which were used as a core for maintaining control algorithms. Several RISC processors were equipped with custom-made VME mezzanine boards providing interfacing, pre-processing and data formatting. These mezzanines are subjects of this paper. They are: RIO-TIC/DAT - time stamp distributor and buffered DT-bus interface, FOL-RIO - optical data formatter and event merger and "TAXI receiver" - handling trigger data of the NA48 Level 2 trigger supervisor. Also the interface between DT-bus and S-link/PCI is described.

  17. MINOS Calibration and NA49 Hadronic Production Studies

    SciTech Connect

    Morse, Robert James

    2003-08-01

    An overview of the current status of the Main Injector Neutrino Oscillation Search (MINOS) is presented. MINOS is a long-baseline experiment with two detectors situated in North America. The near detector is based at the emission point of the NuMI beam at Fermilab, Chicago, the far detector is 735 km downstream in a disused iron mine in Soudan, Minnesota. A third detector, the calibration detector, is used to cross-calibrate these detectors by sampling different particle beams at CERN. A detailed description of the design and construction of the light-injection calibration system is included. Also presented are experimental investigations into proton-carbon collisions at 158 GeV/c carried out with the NA49 experiment at CERN. The NA49 experiment is a Time Projection Chamber (TPC) based experiment situated at CERN's North Area. It is a well established experiment with well known characteristics. The data gained from this investigation are to be used to parameterize various hadronic production processes in accelerator and atmospheric neutrino production. These hadronic production parameters will be used to improve the neutrino generation models used in calculating the neutrino oscillation parameters in MINOS.

  18. Sacramento Metropolitan Area, California

    DTIC Science & Technology

    1992-02-01

    2) the Alert Phase, during which the Corps’ Emergency Operations Center is activated and office and field personnel cooperate with emergency teams... fields provide foraging areas for the red-tailed hawk, Brewer’s blackbird, and Swainson’s hawk, which often nest in nearby riparian areas and use...agricultural fields and annual grassland for feeding. (See EIS/EIR Chapter 10.) Rare, Threatened and Endangered Species. One Federally threatened species

  19. Response of saliva Na/K ratio to changing Na supply of lactating cows under tropical conditions.

    PubMed

    Thiangtum, Wandee; Schonewille, J Thomas; Verstegen, Martin Wa; Arsawakulsudhi, Supot; Rukkwamsuk, Theera; Hendriks, Wouter H

    2017-06-01

    Factorial determination of the sodium (Na) requirement of heat-stressed lactating cows is hindered by accurate estimates of the Na losses through sweat. Direct studies, therefore, may be needed requiring information on the time course of healthy animals to become Na depleted and the subsequent rate of repletion. The rate of Na depletion and subsequent rate of Na repletion with two levels of dietary Na to lactating dairy cows housed under tropical conditions were investigated using the salivary Na/K. The 12 lactating cows (salivary Na/K ratio 14.6) rapidly developed clinical signs of Na deficiency, including pica, polyuria and polydipsia, reduced body weight and reduced milk yield when fed a low-Na ration (0.33 g kg(-1) dry matter (DM)) for 3 weeks. Deficiency symptoms were associated with a rapid decrease in salivary Na/K ratio to <4.3 from 7 to 21 days. Subsequent repletion of the cows with NaCl to a ration concentration of 1.1 or 1.6 g Na kg(-1) DM for 5 weeks did not restore salivary Na/K ratio to values of >6. A daily Na intake of heat-stressed lactating cows to a ration intake of 1.6 g Na kg(-1) DM was insufficient to restore Na deficiency. One week was sufficient to deplete heat-stressed lactating cows of Na, allowing for rapid dose-response studies utilizing the salivary Na/K ratio as a parameter for Na status of cows under tropical conditions. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  20. 300 Area Disturbance Report

    SciTech Connect

    LL Hale; MK Wright; NA Cadoret

    1999-01-07

    The objective of this study was to define areas of previous disturbance in the 300 Area of the U.S. Department of Energy (DOE) Hanford Site to eliminate these areas from the cultural resource review process, reduce cultural resource monitoring costs, and allow cultural resource specialists to focus on areas where subsurface disturbance is minimal or nonexistent. Research into available sources suggests that impacts from excavations have been significant wherever the following construction activities have occurred: building basements and pits, waste ponds, burial grounds, trenches, installation of subsurface pipelines, power poles, water hydrants, and well construction. Beyond the areas just mentioned, substrates in the' 300 Area consist of a complex, multidimen- sional mosaic composed of undisturbed stratigraphy, backfill, and disturbed sediments; Four Geographic Information System (GIS) maps were created to display known areas of disturbance in the 300 Area. These maps contain information gleaned from a variety of sources, but the primary sources include the Hanford GIS database system, engineer drawings, and historic maps. In addition to these maps, several assumptions can be made about areas of disturbance in the 300 Area as a result of this study: o o Buried pipelines are not always located where they are mapped. As a result, cultural resource monitors or specialists should not depend on maps depicting subsurface pipelines for accurate locations of previous disturbance. Temporary roads built in the early 1940s were placed on layers of sand and gravel 8 to 12 in. thick. Given this information, it is likely that substrates beneath these early roads are only minimally disturbed. Building foundations ranged from concrete slabs no more than 6 to 8 in. thick to deeply excavated pits and basements. Buildings constructed with slab foundations are more numerous than may be expected, and minimally disturbed substrates may be expected in these locations. Historic black

  1. Semisynthesis of NaK; a Na+ and K+ conducting ion channel

    PubMed Central

    Linn, Kellie M.; Derebe, Mehebaw G.; Jiang, Youxing; Valiyaveetil, Francis I.

    2010-01-01

    In this contribution, we describe the semisynthesis of NaK, a bacterial non-selective cation channel. In the semisynthesis, the NaK polypeptide is assembled from a recombinantly expressed thioester peptide and a chemically synthesized peptide using the native chemical ligation reaction. We describe a temporary tagging strategy for the purification of the hydrophobic synthetic peptide and demonstrate the efficient ligation of the synthetic peptide with the recombinant peptide thioester to form the semisynthetic NaK polypeptide. Following assembly, the NaK polypeptide is folded in vitro to the native state using lipid vesicles. Functional characterization of the folded semisynthetic NaK channels indicates that it is functionally similar to the wild type protein. We used semisynthesis to substitute aspartate 66 in the selectivity filter region of the NaK channel with the unnatural amino acids, homoserine and cysteine sulfonic acid. Functional analysis of these mutants suggests that the presence of a negatively charged residue in the vicinity of the ion binding sites is necessary for optimal flux of ions through the NaK channel. PMID:20415433

  2. Semisynthesis of NaK, a Na(+) and K(+) conducting ion channel.

    PubMed

    Linn, Kellie M; Derebe, Mehabaw G; Jiang, Youxing; Valiyaveetil, Francis I

    2010-06-01

    In this contribution, we describe the semisynthesis of NaK, a bacterial nonselective cation channel. In the semisynthesis, the NaK polypeptide is assembled from a recombinantly expressed thioester peptide and a chemically synthesized peptide using the native chemical ligation reaction. We describe a temporary tagging strategy for the purification of the hydrophobic synthetic peptide and demonstrate the efficient ligation of the synthetic peptide with the recombinant peptide thioester to form the semisynthetic NaK polypeptide. Following assembly, the NaK polypeptide is folded in vitro to the native state using lipid vesicles. Functional characterization of the folded semisynthetic NaK channels indicates that it is functionally similar to the wild-type protein. We used semisynthesis to substitute aspartate 66 in the selectivity filter region of the NaK channel with the unnatural amino acids homoserine and cysteine sulfonic acid. Functional analysis of these mutants suggests that the presence of a negatively charged residue in the vicinity of the ion binding sites is necessary for optimal flux of ions through the NaK channel.

  3. Study on Na layer response to geomagnetic activities based on Odin/OSIRIS Na density data

    NASA Astrophysics Data System (ADS)

    Tsuda, Takuo; Nakamura, Takuji; Hedin, Jonas; Gumbel, Jorg; Hosokawa, Keisuke; Ejiri, Mitsumu K.; Nishiyama, Takanori; Takahashi, Toru

    2016-07-01

    The Na layer is normally distributed from 80 to 110 km, and the height range is corresponding to the ionospheric D and E region. In the polar region, the energetic particles precipitating from the magnetosphere can often penetrate into the E region and even into the D region. Thus, the influence of the energetic particles to the Na layer is one of interests in the aspect of the atmospheric composition change accompanied with the auroral activity. There are several previous studies in this issue. For example, recently, we have reported an initial result on a clear relationship between the electron density increase (due to the energetic particles) and the Na density decrease from observational data sets obtained by Na lidar, EISCAT VHF radar, and optical instruments at Tromsoe, Norway on 24-25 January 2012. However, all of the previous studies had been carried out based on case studies by ground-based lidar observations. In this study, we have performed, for the first time, statistical analysis using Na density data from 2004 to 2009 obtained with the Optical Spectrograph and InfraRed Imager System (OSIRIS) onboard Odin satellite. In the presentation, we will show relationship between the Na density and geomagnetic activities, and its latitudinal variation. Based on these results, the Na layer response to the energetic particles will be discussed.

  4. Role of the Na(+)-translocating NADH:quinone oxidoreductase in voltage generation and Na(+) extrusion in Vibrio cholerae.

    PubMed

    Vorburger, Thomas; Nedielkov, Ruslan; Brosig, Alexander; Bok, Eva; Schunke, Emina; Steffen, Wojtek; Mayer, Sonja; Götz, Friedrich; Möller, Heiko M; Steuber, Julia

    2016-04-01

    For Vibrio cholerae, the coordinated import and export of Na(+) is crucial for adaptation to habitats with different osmolarities. We investigated the Na(+)-extruding branch of the sodium cycle in this human pathogen by in vivo (23)Na-NMR spectroscopy. The Na(+) extrusion activity of cells was monitored after adding glucose which stimulated respiration via the Na(+)-translocating NADH:quinone oxidoreductase (Na(+)-NQR). In a V. cholerae deletion mutant devoid of the Na(+)-NQR encoding genes (nqrA-F), rates of respiratory Na(+) extrusion were decreased by a factor of four, but the cytoplasmic Na(+) concentration was essentially unchanged. Furthermore, the mutant was impaired in formation of transmembrane voltage (ΔΨ, inside negative) and did not grow under hypoosmotic conditions at pH8.2 or above. This growth defect could be complemented by transformation with the plasmid encoded nqr operon. In an alkaline environment, Na(+)/H(+) antiporters acidify the cytoplasm at the expense of the transmembrane voltage. It is proposed that, at alkaline pH and limiting Na(+) concentrations, the Na(+)-NQR is crucial for generation of a transmembrane voltage to drive the import of H(+) by electrogenic Na(+)/H(+) antiporters. Our study provides the basis to understand the role of the Na(+)-NQR in pathogenicity of V. cholerae and other pathogens relying on this primary Na(+) pump for respiration. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Synthesis, characterization and application of nanozeolite NaX from Vietnamese kaolin

    NASA Astrophysics Data System (ADS)

    Ngoc, Don Ta; Huyen Pham, Thanh; Nguyen, Khanh Dieu Hong

    2013-12-01

    This paper presents the results of synthesis of nanozeolite NaX from Vietnamese kaolin. Influence factors on the control of crystal sizes and application of synthesized materials as adsorbent for organic compound are discussed. The results show that there are several factors that influence the synthesis. When water content in gel increases, crystal size of NaX increases sharply. The increase of alkaline and silica contents increases the crystallinity and decreases the particle size of nano NaX, and the particle size reaches the minimum at Na2O/Al2O3 = 5.0 and SiO2/Al2O3 = 4.0. Crystal sizes formed at low crystallizing temperature are smaller than those formed at higher temperature. Ageing time and crystallizing time strongly influence the crystallinity and crystal size, which is related to the number of crystal seeds formed during ageing period, the growth of seed and the partial solubility of crystal at maximum formation. Nano NaX was characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) adsorption, Fourier transform infrared (FTIR) and simultaneous thermogravimetry-differential scanning calorimetry (TG/DSC). At optimized synthesis conditions, nano NaX has surface area of 573 m2 g-1with external surface area of 92 m2 g-1, pore size distribution at 0.81 and 10.8 nm, average crystal size of 25 nm and thermal stability up to 789 °C. This material can adsorb cumene rapidly with high adsorption capacity and stability.

  6. Na(+) dependence of K(+) -induced natriuresis, kaliuresis and Na(+) /Cl(-) cotransporter dephosphorylation.

    PubMed

    Jensen, I S; Larsen, C K; Leipziger, J; Sørensen, M V

    2016-09-01

    High dietary K(+) intake is associated with protection against hypertension. In mammals, acute K(+) intake induces natriuresis and kaliuresis, associated with a marked dephosphorylation of the renal Na(+) /Cl(-) cotransporter (NCC). It has been suggested that reduced activity of NCC increases the driving force for more distal tubular epithelial Na(+) channel (ENaC)-dependent K(+) secretion. This study investigated the ENaC dependence of urinary K(+) and Na(+) excretion following acute K(+) loading. Mice were fed low (0.03%), control (0.2%) or high (2%) Na(+) diets for 25 days to preserve or promote Na(+) loss and thus ENaC activity. Once a week, the mice received either K(+) -containing gavage or a control gavage. Following the gavage treatment, the mice were placed in metabolic cages and urine was collected in real time. ENaC dependence of kaliuresis was assessed by benzamil injections prior to gavage. We confirmed that dietary Na(+) content is inversely related to plasma aldosterone, NCC phosphorylation and ENaC cleavage products. The novel findings were as follows: (i) acute K(+) feeding caused NCC dephosphorylation in all dietary groups; (ii) under all dietary conditions, K(+) loading induced natriuresis; (iii) high Na(+) diet markedly reduced the K(+) excretion following K(+) gavage; (iv) benzamil injection prior to K(+) loading increased natriuresis, decreased kaliuresis and eliminated the differences between the dietary groups. These data indicate that acute K(+) -induced kaliuresis is ENaC dependent. Maximal K(+) excretion rates are attenuated when ENaC is physiologically down-regulated or pharmacologically blocked. NCC is dephosphorylated following acute K(+) loading under all dietary Na(+) regimens. This leads to natriuresis, even in severely Na(+) -restricted animals. © 2016 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  7. Cumulative effect of nitrogen and sulphur on Brassica juncea L. genotypes under NaCl stress.

    PubMed

    Siddiqui, Manzer H; Mohammad, Firoz; Khan, M Masrooor A; Al-Whaibi, Mohamed H

    2012-01-01

    In the present study, N and S assimilation, antioxidant enzymes activity, and yield were studied in N and S-treated plants of Brassica juncea (L.) Czern. & Coss. (cvs. Chuutki and Radha) under salt stress. The treatments were given as follows: (1) NaCl(90) mM+N(0)S(0) mg kg(-1) sand (control), (2) NaCl(90) mM+N(60)S(0) mg kg(-1) sand, (3) NaCl(90) mM+N(60)S(20) mg kg(-1) sand, (4) NaCl(90) mM+N(60)S(40) mg kg(-1) sand, and (5) NaCl(90) mM+N(60)S(60) mg kg(-1) sand. The combined application of N (60 mg kg(-1) sand) and S (40 mg kg(-1) sand) proved beneficial in alleviating the adverse effect of salt stress on growth attributes (shoot length plant(-1), fresh weight plant(-1), dry weight plant(-1), and area leaf(-1)), physio-biochemical parameters (carbonic anhydrase activity, total chlorophyll, adenosine triphosphate-sulphurylase activity, leaf N, K and Na content, K/Na ratio, activity of nitrate reductase, nitrite reductase, glutamine synthetase, glutamate synthase, catalase, superoxide dismutase, ascorbate peroxidase and glutathione reductase, and content of glutathione and ascorbate), and yield attributes (pods plant(-1), seeds pod(-1), and seed yield plant(-1)). Therefore, it is concluded that combined application of N and S induced the physiological and biochemical mechanisms of Brassica. The stimulation of antioxidant enzymes activity and its synergy with N and S assimilation may be one of the important mechanisms that help the plants to tolerate the salinity stress and resulted in an improved yield.

  8. Long Life Na/NiCl2 Cells

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V. (Inventor); Surampudi, Subbarao (Inventor); Halpert, Gerald (Inventor)

    1996-01-01

    The premature capacity failure of Na/NiCl2 secondary cells due to agglomeration of nickel particles on the surface of the NiCl2 cathode is prevented by addition of a minor amount such as 10 percent by weight of a transition metal such as Co, Fe or Mn to the cathode. The chlorides of the transition metals have lower potentials than nickel chloride and chlorinate during charge. A uniform dispersion of the transition metals in the cathodes prevents agglomeration of nickel, maintains morphology of the electrode, maintains the electrochemical area of the electrode and thus maintains capacity of the electrode. The additives do not effect sintering. The addition of sulfur to the liquid catholyte is expected to further reduce agglomeration of nickel in the cathode.

  9. Electronic Polarisability of NaNO2-NaNO3 and NaOH-NaNO3 Ionic Melts and Effective Ionic Radius of OH-

    NASA Astrophysics Data System (ADS)

    Iwadate, Yasuhiko; Ohnishi, Ryosuke; Ohkubo, Takahiro

    2017-01-01

    Molar volumes and refractive indexes of molten NaNO2-NaNO3 and NaOH-NaNO3 systems were measured by dilatometry and goniometry, respectively. The molar volumes of both systems increased with increasing temperature. Refractive indexes decreased with a rise of temperature or with increasing wavelength of the incident visible light. Assuming that the electronic polarisability is inherent in an ion, the electronic polarisability of a OH- ion in the melt was estimated from the Lorentz-Lorenz equation to be 1.26×10-30 m3, being comparable with that in the crystal. The effective ionic radius of a OH- ion was evaluated from the obtained electronic polarisability to be 1.34×10-10 m, using the correlation between the third power of the ionic radius and the electronic polarisability of an ion so far reported. The effective ionic radius obtained in this work was in good agreement with that assigned by Shannon.

  10. Light-induced drift of Na atoms

    NASA Astrophysics Data System (ADS)

    Werij, H. G. C.; Woerdman, J. P.

    1988-10-01

    Light can induce a flux of optically absorbing particles immersed in a buffer gas, when these particles have a different mobility in the ground and excited state. This paper presents a study of light-induced drift (LID) of Na atoms in noble gases, which can be regarded as the “canonical” system for experiments in this field. We have experimentally studied the LID effect in the optically thin and the optically thick regimes. Parameters which have been varied are laser frequency, laser intensity, buffer gas pressure and buffer gas species. This work gives the first critical comparison of LID experiments with realistic theory in which the multilevel complications of the Na atom have been incorporated. In the optically thick case (“optical piston”) one can distinguish the open cell and the closed cell regimes. Effects of adsorption and desorption of Na atoms at the surface of the cell wall have been incorporated into the theory. The experimental data are in excellent agreement with the results of a four-level rate-equation model for LID which incorporates the fine and hyperfine structure of the level scheme of the Na absorbers.

  11. Mechanisms contributing to the cardiac inotropic effect of Na pump inhibition and reduction of extracellular Na

    PubMed Central

    1987-01-01

    Reduction of the transsarcolemmal [Na] gradient in rabbit cardiac muscle leads to an increase in the force of contraction. This has frequently been attributed to alteration of Ca movements via the sarcolemmal Na/Ca exchange system. However, the specific mechanisms that mediate the increased force at individual contractions have not been clearly established. In the present study, the [Na] gradient was decreased by reduction of extracellular [Na] or inhibition of the Na pump by either the cardioactive steroid acetylstrophanthidin or by reduction of extracellular [K]. Contractile performance and changes in extracellular Ca (sensed by double-barreled Ca-selective microelectrodes) were studied in order to elucidate the underlying basis for the increase in force. In the presence of agents that inhibit sarcoplasmic reticulum (SR) function (10 mM caffeine, 100-500 nM ryanodine), reduction of the [Na] gradient produced increases in contractile force similar to that observed in the absence of caffeine or ryanodine. It is concluded that an intact, functioning SR is not required for the inotropic effect of [Na] gradient reduction (at least in rabbit ventricle). However, this does not exclude a possible contribution of enhanced SR Ca release in the inotropic response to [Na] gradient reduction in the absence of caffeine or ryanodine. Acetylstrophanthidin (3-5 microM) usually leads to an increase in the magnitude of extracellular Ca depletions associated with individual contractions. However, acetylstrophanthidin can also increase extracellular Ca accumulation during the contraction, especially at potentiated contractions. This extracellular Ca accumulation can be suppressed by ryanodine and it is suggested that this apparent enhancement of Ca efflux is secondary to an enhanced release of Ca from the SR. Under conditions where Ca efflux during contractions is minimized (after a rest interval in the presence of ryanodine), acetylstrophanthidin increased both the rate and the

  12. Thermal and carbothermic decomposition of Na2CO3 and Li2CO3

    NASA Astrophysics Data System (ADS)

    Kim, Jong-Wan; Lee, Hae-Geon

    2001-02-01

    In order to elucidate the decomposition mechanism of Na2CO3 and Li2CO3 in mold-powder systems employed in the continuous casting of steel, decompositions of Na2CO3 and Li2CO3 were investigated using thermogravimetric (TG) and differential scanning calorimetric (DSC) methods at temperatures up to 1200 °C, under a flow of argon gas. For the case of pure Na2CO3, the thermal decomposition started from its melting point and continued as the temperature was increased, but at a very slow rate. For Li2CO3, however, the decomposition occurred at much faster rates than that for Na2CO3. When carbon black was added to the carbonate particles, the decomposition rates of both Na2CO3 and Li2CO3 were significantly enhanced. From mass-balanced calulations and X-ray diffraction (XRD) analyses of the reaction products, it is concluded that decompositions of Na2CO3 and Li2CO3 with carbon black take place according to the respective reactions of Na2CO3 (1) + 2C (s) = 2Na (g) + 3CO (g) and Li2CO3 (l) + C (s) = Li2O (s) + 2CO (g). It was found that liquid droplets of Na2CO3 were initially isolated due to carbon particles surrounding them, but, as the carbon particles were consumed, the liquid droplets were gradually agglomerated. This effected a reduction of the total surface area of the carbonate, resulting in a dependence of the decomposition rate on the amount of carbon black. For the case of Li2CO3, on the other hand, hardly any agglomeration occurred up to the completion of decomposition, and, hence, the rate was almost independent of the amount of carbon black mixed. The apparent activation energies for the decomposition of Na2CO3 and Li2CO3 with carbon black were found to be similar and were estimated to be 180 to 223 kJ mole-1.

  13. 200 Area Interim Storage Area Technical Safety Requirements

    SciTech Connect

    CARRELL, R.D.

    2000-03-15

    The 200 Area Interim Storage Area Technical Safety Requirements define administrative controls and design features required to ensure safe operation during receipt and storage of canisters containing spent nuclear fuel. This document is based on the 200 Area Interim Storage Area, Annex D, Final Safety Analysis Report which contains information specific to the 200 Area Interim Storage Area.

  14. Intracellular Na(+) and metabolic modulation of Na/K pump and excitability in the rat suprachiasmatic nucleus neurons.

    PubMed

    Wang, Yi-Chi; Yang, Jyh-Jeen; Huang, Rong-Chi

    2012-10-01

    Na/K pump activity and metabolic rate are both higher during the day in the suprachiasmatic nucleus (SCN) that houses the circadian clock. Here we investigated the role of intracellular Na(+) and energy metabolism in regulating Na/K pump activity and neuronal excitability. Removal of extracellular K(+) to block the Na/K pump excited SCN neurons to fire at higher rates and return to normal K(+) to reactivate the pump produced rebound hyperpolarization to inhibit firing. In the presence of tetrodotoxin to block the action potentials, both zero K(+)-induced depolarization and rebound hyperpolarization were blocked by the cardiac glycoside strophanthidin. Ratiometric Na(+) imaging with a Na(+)-sensitive fluorescent dye indicated saturating accumulation of intracellular Na(+) in response to pump blockade with zero K(+). The Na(+) ionophore monensin also induced Na(+) loading and hyperpolarized the membrane potential, with the hyperpolarizing effect of monensin abolished in zero Na(+) or by pump blockade. Conversely, Na(+) depletion with Na(+)-free pipette solution depolarized membrane potential but retained residual Na/K pump activity. Cyanide inhibition of oxidative phosphorylation blocked the Na/K pump to depolarize resting potential and increase spontaneous firing in most cells, and to raise intracellular Na(+) levels in all cells. Nonetheless, the Na/K pump was incompletely blocked by cyanide but completely blocked by iodoacetate to inhibit glycolysis, indicating the involvement of both oxidative phosphorylation and glycolysis in fueling the Na/K pump. Together, the results indicate the importance of intracellular Na(+) and energy metabolism in regulating Na/K pump activity as well as neuronal excitability in the SCN neurons.

  15. Preparation of activated carbon from wet sludge by electrochemical-NaClO activation.

    PubMed

    Miao, Chen; Ye, Caihong; Zhu, Tianxing; Lou, Ziyang; Yuan, Haiping; Zhu, Nanwen

    2014-01-01

    Activated carbon (AC) from sludge is one potential solution for sewage sludge disposal, while the drying sludge is cost and time consuming for preparation. AC preparation from the wet sludge with electrochemical-NaClO activation was studied in this work. Three pretreatment processes, i.e. chemical activation, electrolysis and electrochemical-reagent reaction, were introduced to improve the sludge-derived AC properties, and the optimum dosage of reagent was tested from the 0.1:1 to 1:1 (mass rate, reagent:dried sludge). It was shown that the electrochemical-NaClO preparation is the best method under the test conditions, in which AC has the maximum Brunauer, Emmett and Teller area of 436 m²/g at a mass ratio of 0.7. Extracellular polymeric substances in sludge can be disintegrated by electrochemical-NaClO pretreatment, with a disintegration degree of more than 45%. The percentage of carbon decreased from 34.16 to 8.81 after treated by electrochemical-NaClO activation. Fourier transform infrared spectra showed that a strong C-Cl stretching was formed in electrochemical-NaClO prepared AC. The maximum adsorption capacity of AC reaches 109 mg/g on MB adsorption experiment at pH 10 and can be repeated for three times with high removal efficiency after regeneration.

  16. Na(+), K(+)-ATPase dysfunction causes cerebrovascular endothelial cell degeneration in rat prefrontal cortex slice cultures.

    PubMed

    Kurauchi, Yuki; Hisatsune, Akinori; Seki, Takahiro; Katsuki, Hiroshi

    2016-08-01

    Cerebrovascular endothelial cell dysfunction resulting in imbalance of cerebral blood flow contributes to the onset of psychiatric disorders such as depression, schizophrenia and bipolar disorder. Although decrease in Na(+), K(+)-ATPase activity has been reported in the patients with schizophrenia and bipolar disorder, the contribution of Na(+), K(+)-ATPase to endothelial cell dysfunction remains poorly understood. Here, by using rat neonatal prefrontal cortex slice cultures, we demonstrated that pharmacological inhibition of Na(+), K(+)-ATPase by ouabain induced endothelial cell injury. Treatment with ouabain significantly decreased immunoreactive area of rat endothelial cell antigen-1 (RECA-1), a marker of endothelial cells, in a time-dependent manner. Ouabain also decreased Bcl-2/Bax ratio and phosphorylation level of glycogen synthase kinase 3β (GSK3β) (Ser9), which were prevented by lithium carbonate. On the other hand, ouabain-induced endothelial cell injury was exacerbated by concomitant treatment with LY294002, an inhibitor of phosphoinositide 3- (PI3-) kinase. We also found that xestospongin C, an inhibitor of inositol triphosphate (IP3) receptor, but not SEA0400, an inhibitor of Na(+), Ca(2+) exchanger (NCX), protected endothelial cells from cytotoxicity of ouabain. These results suggest that cerebrovascular endothelial cell degeneration induced by Na(+), K(+)-ATPase inhibition resulting in Ca(2+) release from endoplasmic reticulum (ER) and activation of GSK3β signaling underlies pathogenesis of these psychiatric disorders.

  17. Praseodymium doped NaYF4 nanocrystals in oxyfluoride glass-ceramics; morphological and spectroscopic studies.

    PubMed

    Dominiak-Dzik, G

    2009-04-01

    The synthesis, morphology, optical properties and excited state dynamics of the Pr-doped NaYF4 nanocrystals in glass-ceramics are presented. The crystalline cubic NaYF4:Pr were synthesized by the controlled heat-treatment of multicomponent oxyfluoride glass based on silica and YF3. A series of the two-hour heat treatments at 620-660 degrees C were carried out yielding visually transparent materials. Above 660 degrees C an opaque material was obtained. The crystalline phase was characterized by the X-ray powder diffraction (XRD), high-resolution transmission electron microscopy (TEM) and selected area electron diffraction (SAED). The effect of ceramming temperature on the NaYF4:Pr cell parameter (a = 5.470 A for NaYF4 and 5.4899 A, 5.4979 A and 5.5378 A in glass-ceramics) and particle average size (15-40 nm) was observed. Optical characteristics of formed glass-ceramics were favorably affected by the Pr3+ ions in well-defined sites of NaYF4; emission intensities increased and luminescence decay curves become single exponential with the longer corresponding lifetimes.

  18. Laser trapping of {sup 21}Na atoms

    SciTech Connect

    Lu, Zheng-Tian

    1994-09-01

    This thesis describes an experiment in which about four thousand radioactive {sup 21}Na (t{sub l/2} = 22 sec) atoms were trapped in a magneto-optical trap with laser beams. Trapped {sup 21}Na atoms can be used as a beta source in a precision measurement of the beta-asymmetry parameter of the decay of {sup 21}Na {yields} {sup 21}Ne + {Beta}{sup +} + v{sub e}, which is a promising way to search for an anomalous right-handed current coupling in charged weak interactions. Although the number o trapped atoms that we have achieved is still about two orders of magnitude lower than what is needed to conduct a measurement of the beta-asymmetry parameter at 1% of precision level, the result of this experiment proved the feasibility of trapping short-lived radioactive atoms. In this experiment, {sup 21}Na atoms were produced by bombarding {sup 24}Mg with protons of 25 MeV at the 88 in. Cyclotron of Lawrence Berkeley Laboratory. A few recently developed techniques of laser manipulation of neutral atoms were applied in this experiment. The {sup 21}Na atoms emerging from a heated oven were first transversely cooled. As a result, the on-axis atomic beam intensity was increased by a factor of 16. The atoms in the beam were then slowed down from thermal speed by applying Zeeman-tuned slowing technique, and subsequently loaded into a magneto-optical trap at the end of the slowing path. The last two chapters of this thesis present two studies on the magneto-optical trap of sodium atoms. In particular, the mechanisms of magneto-optical traps at various laser frequencies and the collisional loss mechanisms of these traps were examined.

  19. [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.

  20. Effect of environmental temperature on the turnover of noradrenaline in hypothalamus and other areas of rat brain

    PubMed Central

    Simmonds, M. A.

    1969-01-01

    1. The hypothesis that noradrenaline (NA) may be a transmitter in the temperature regulating centre in the hypothalamus is based on the changes in rectal temperature induced by injection of large doses of NA into the brain. As an alternative approach, the effect of environmental temperature on the rate of turnover of endogenous NA in the hypothalamus has been studied. 2. Small amounts of tritium labelled noradrenaline [3H]NA were injected into the c.s.f. of rats in order to label radioactively the endogenous NA in the brain. The rats were then exposed to environmental temperatures of 9, 17, 24 and 32° C. The rates of disappearance of [3H]NA from discrete areas of brain were taken as indices of the rates of turnover of endogenous NA in those areas. 3. The rate of disappearance of [3H]NA from the hypothalamus was three times as fast at 9 and 32° C as at 17 or 24° C. There were no such significant differences from the pre-optic area or `rest of brain' (whole brain minus hypothalamus, pre-optic area, cerebellum and medulla). 4. The endogenous concentrations of NA were not altered by the experimental procedures in any of the areas of brain studied. 5. The rats maintained normal rectal temperatures at environmental temperatures of 9, 17 and 24° C but became 2·8° C hyperthermic at 32° C. 6. It is concluded that mild conditions of both heat and cold resulted in an increased turnover of NA in specific nerve terminals in the hypothalamus. Since the rats were thermoregulating normally, the nerve terminals involved are regarded as forming a part of the central temperature regulating centre. PMID:5821872

  1. The Na4(+3) Clusters in Sodium Sodalite

    DTIC Science & Technology

    1992-05-15

    ATES COVOIN0i-15-92 Technical 06-01-91 to 05-31-92 4. TITLE ANA SUGTITLE S. RNORNG NUMBER The Na4+ 3 Clusters in Sodium Sodalite NN l14-e0-J-se59a 𔄀...3 [AlSiO 4]3 sodalite prepared by high vacuum deposition of sodium atoms. The samples with a Na 43 +:Na33+ cluster ratio up to 1:10 show a single...absorption feature with -m. = 628 nm (1.99 eV). The absorption originates from the individual sodalite cages containing Na 43+ cluster. For the Na 43+:Na

  2. Large area LED package

    NASA Astrophysics Data System (ADS)

    Goullon, L.; Jordan, R.; Braun, T.; Bauer, J.; Becker, F.; Hutter, M.; Schneider-Ramelow, M.; Lang, K.-D.

    2015-03-01

    Solid state lighting using LED-dies is a rapidly growing market. LED-dies with the needed increasing luminous flux per chip area produce a lot of heat. Therefore an appropriate thermal management is required for general lighting with LEDdies. One way to avoid overheating and shorter lifetime is the use of many small LED-dies on a large area heat sink (down to 70 μm edge length), so that heat can spread into a large area while at the same time light also appears on a larger area. The handling with such small LED-dies is very difficult because they are too small to be picked with common equipment. Therefore a new concept called collective transfer bonding using a temporary carrier chip was developed. A further benefit of this new technology is the high precision assembly as well as the plane parallel assembly of the LED-dies which is necessary for wire bonding. It has been shown that hundred functional LED-dies were transferred and soldered at the same time. After the assembly a cost effective established PCB-technology was applied to produce a large-area light source consisting of many small LED-dies and electrically connected on a PCB-substrate. The top contacts of the LED-dies were realized by laminating an adhesive copper sheet followed by LDI structuring as known from PCB-via-technology. This assembly can be completed by adding converting and light forming optical elements. In summary two technologies based on standard SMD and PCB technology have been developed for panel level LED packaging up to 610x 457 mm2 area size.

  3. Furosemide-sensitive Na and K fluxes in human red cells. Net uphill Na extrusion and equilibrium properties

    PubMed Central

    1986-01-01

    This paper reports experiments designed to find the concentrations of internal and external Na and K at which inward and outward furosemide- sensitive (FS) Na and K fluxes are equal, so that there is no net FS movement of Na and K. The red cell cation content was modified by using the ionophore nystatin, varying cell Na (Nai) from 0 to 34 mM (K substitution, high-K cells) and cell K (Ki) from 0 to 30 mM (Na substitution, high-Na cells). All incubation media contained NaCl (Nao = 130 or 120 nM), and KCl (Ko = 0-30 mM). In high-K cells, incubated in the absence of Ko, there was net extrusion of Na through the FS pathway. The net FS Na extrusion increased when Nai was increased. Low concentrations of Ko (0-6 mM) slightly stimulated, whereas higher concentrations of Ko inhibited, FS Na efflux. Increasing Ko stimulated the FS Na influx (K0.5 = 4 mM). Under conditions similar to those that occur in vivo (Nai = 10, Ki = 130, Nao = 130, Ko = 4 mM, Cli/Clo = 0.7), net extrusion of Na occurs through the FS pathway (180-250 mumol/liter cell X h). The concentration of Ko at which the FS Na influx and efflux and the FS K influx and efflux become equal increased when Nai increased in high-K cells and when Ki was increased in high-Na cells. The net FS Na and K fluxes both approached zero at similar internal and external Na and K concentrations. In high-K cells, under conditions when net Na and K fluxes were near zero, the ratio of FS Na to FS K unidirectional flux was found to be 2:3. In high-K cells, the empirical expression (Nai/Nao)2(Ki/Ko)3 remained at constant value (apparent equilibrium constant, Kappeq +/- SEM = 22 +/- 2) for each set of internal and external cation concentrations at which there was no net Na flux. These results indicate that in the physiological region of concentrations of internal and external Na, K, and Cl, the stoichiometry of the FS Na and K fluxes is 2 Na:3 K. In high-Na cells under conditions when net FS Na and K fluxes were near zero, the ratio of

  4. The solubility of Cr(OH){sub 3}(am) in concentrated NaOH and NaOH-NaNO{sub 3} solutions

    SciTech Connect

    Felmy, A.R.; Rai, D.; Fulton, R.W.

    1994-08-01

    Chromium is a major component of the Hanford waste tank sludges, and the presence of Cr in the sludges is a significant concern in the disposal of these sludges because Cr can interfere with the formation of waste glasses. One of the current pretreatment strategies for removing constituents that can interfere with glass formation, such as P and Cr, is to wash/dissolve the sludges in basic NaOH solutions. The solubility of Cr(OH){sub 3}(am) was measured in concentrated NaOH ranging in concentration from 0.1M to 6.0M and in NaOH-NaNO{sub 3} solutions with fixed NaOH concentration and variable NaNO{sub 3} concentration at room temperature (22--23 C). Equilibrium between solids and solutions was approached relatively slowly and required approximately 60--70 days before steady-state concentrations were reached. A thermodynamic model, based upon the Pitzer equations, was developed from the solubility data in NaOH, which includes only two aqueous Cr species (Cr(OH){sub 4}{sup {minus}} and NaCr(OH){sub 4}(aq)) and ion-interaction parameters for Na{sup +} with Cr(OH){sub 4}{sup {minus}}. This model was then tested in the mixed NaOH-NaNO{sub 3} solutions and found to be reliable.

  5. Effects of non-uniform root zone salinity on water use, Na+ recirculation, and Na+ and H+ flux in cotton.

    PubMed

    Kong, Xiangqiang; Luo, Zhen; Dong, Hezhong; Eneji, A Egrinya; Li, Weijiang

    2012-03-01

    A new split-root system was established through grafting to study cotton response to non-uniform salinity. Each root half was treated with either uniform (100/100 mM) or non-uniform NaCl concentrations (0/200 and 50/150 mM). In contrast to uniform control, non-uniform salinity treatment improved plant growth and water use, with more water absorbed from the non- and low salinity side. Non-uniform treatments decreased Na(+) concentrations in leaves. The [Na(+)] in the '0' side roots of the 0/200 treatment was significantly higher than that in either side of the 0/0 control, but greatly decreased when the '0' side phloem was girdled, suggesting that the increased [Na(+)] in the '0' side roots was possibly due to transportation of foliar Na(+) to roots through phloem. Plants under non-uniform salinity extruded more Na(+) from the root than those under uniform salinity. Root Na(+) efflux in the low salinity side was greatly enhanced by the higher salinity side. NaCl-induced Na(+) efflux and H(+) influx were inhibited by amiloride and sodium orthovanadate, suggesting that root Na(+) extrusion was probably due to active Na(+)/H(+) antiport across the plasma membrane. Improved plant growth under non-uniform salinity was thus attributed to increased water use, reduced leaf Na(+) concentration, transport of excessive foliar Na(+) to the low salinity side, and enhanced Na(+) efflux from the low salinity root.

  6. OLED area illumination source

    SciTech Connect

    Foust, Donald Franklin; Duggal, Anil Raj; Shiang, Joseph John; Nealon, William Francis; Bortscheller, Jacob Charles

    2008-03-25

    The present invention relates to an area illumination light source comprising a plurality of individual OLED panels. The individual OLED panels are configured in a physically modular fashion. Each OLED panel comprising a plurality of OLED devices. Each OLED panel comprises a first electrode and a second electrode such that the power being supplied to each individual OLED panel may be varied independently. A power supply unit capable of delivering varying levels of voltage simultaneously to the first and second electrodes of each of the individual OLED panels is also provided. The area illumination light source also comprises a mount within which the OLED panels are arrayed.

  7. CHANCHELULLA ROADLESS AREA, CALIFORNIA.

    USGS Publications Warehouse

    Huber, Donald F.; Stebbins, Scott A.

    1984-01-01

    On the basis of a mineral survey there seems to be little likelihood for the occurrence of mineral resources in the Chanchelulla Roadless Area, California, except for a demonstrated resource of about 7200 tons containing 0. 084 oz gold/ton, 0. 84 oz silver/ton, and accessory copper at the Chanchelulla prospect. This prospect is located on a northwest-trending quartz vein. Limestone and small amounts of magnetite occur in the area but on the basis of available data no resources are identified. No potential for energy resources was identified.

  8. SELKIRK ROADLESS AREA, IDAHO.

    USGS Publications Warehouse

    Miller, Fred K.; Benham, John R.

    1984-01-01

    On the basis of mineral-resource surveys the Selkirk Roadless Area, Idaho has little promise for the occurrence of mineral or energy resources. Molybdenum, lead, uranium, thorium, chromium, tungsten, zirconium, and several rare-earth elements have been detected in panned concentrates from samples of stream sediment, but no minerals containing the first five elements were found in place, nor were any conditions conducive to their concentration found. Zirconium, thorium, and the rare earths occur in sparsely disseminated accessory minerals in granitic rocks and no resource potential is identified. There is no history of mining in the roadless area and there are no oil, gas, mineral, or geothermal leases or current claims.

  9. Explosively activated egress area

    NASA Technical Reports Server (NTRS)

    Bement, L. J.; Bailey, J. W. (Inventor)

    1983-01-01

    A lightweight, add on structure which employs linear shaped pyrotechnic charges to smoothly cut an airframe along an egress area periphery is provided. It compromises reaction surfaces attached to the exterior surface of the airframe's skin and is designed to restrict the skin deflection. That portion of the airframe within the egress area periphery is jettisoned. Retention surfaces and sealing walls are attached to the interior surface of the airframe's skin and are designed to shield the interior of the aircraft during detonation of the pyrotechnic charges.

  10. Hypo-osmotic stimulation of active Na+ transport in frog muscle: apparent upregulation of Na+ pumps.

    PubMed

    Venosa, R A

    1991-03-01

    The purpose of this work was to determine if hypotonicity, in addition to the stimulation of active Na+ transport (Venosa, R.A., 1978, Biochim. Biophys. Acta 510:378-383), promoted changes in (i) active K+ influx, (ii) passive Na+ and K+ fluxes, and (iii) the number of 3H-ouabain binding sites. The results indicate that a reduction of external osmotic pressure (pi) to one-half of its normal value (pi = 0.5) produced the following effects: (i) an increase in active K+ influx on the order of 160%, (ii) a 20% reduction in Na+ influx and K+ permeability (PK), and (iii) a 40% increase in the apparent density of ouabain binding sites. These data suggest that the hypotonic stimulation of the Na+ pump is not caused by an increased leak of either Na+ (inward) or K+ (outward). It is unlikely that the stimulation of active Na+ extrusion and the rise in the apparent number of pump sites produced by hypotonicity were due to a reduction of the intracellular ionic strength. It appears that, at least in part, the stimulation of active Na+ transport takes place whenever muscles are transferred from one medium to another of lower tonicity even if neither one was hypotonic (for instance pi = 2 to pi = 1 transfer). Comparison of the present results with those previously reported indicate that in addition to the number of pump sites, the cycling rate of the pump is increased by hypotonicity. Active Na+ and K+ fluxes were not significantly altered by hypertonicity (pi = 2).

  11. Studies of Inelastic Collisions of NaK and NaCs Molecules with Atomic Perturbers

    NASA Astrophysics Data System (ADS)

    Jones, Joshua A.

    We have investigated collisions of NaK molecules in the first excited state [2(A)1Sigma+], with Ar and He collision partners using laser-induced fluorescence spectroscopy (LIF) and polarization-labeling (PL) spectroscopy in a two-step excitation scheme. Additionally, we have investigated collisions of NaCs molecules in the first excited state [2(A)1Sigma +] with Ar and He perturbers using the LIF technique. We use a pump-probe, two-step excitation process. The pump laser prepares the molecule in a particular ro-vibrational (v, J) level in the A state. The probe laser frequency is scanned over transitions to the 31Π in NaK or to the 53Π in NaCs. In addition to observing strong direct lines, we also see weak collisional satellite lines that arise from collisions in the intermediate state that take the molecule from the prepared level (v, J) to level (v, J + Delta J). The ratio of the intensity of the collisional line to the intensity of the direct line in LIF and PL yield information about population and orientation transfer. Our results show a propensity for DeltaJ=even collisions of NaK with Ar and an even stronger propensity for collisions with He. Collisions of NaCs with Ar do not show any such J=even propensity. Preliminary investigations of collisions of NaCs with He seem to indicate a slight J=even propensity. In addition, we observe that rotationally inelastic collisions of excited NaK molecules with potassium atoms destroy almost all of the orientation, while collisions with argon destroy about one third to two thirds and collisions with helium destroy only about zero to one third of the initial orientation.

  12. K+ Congeners That Do Not Compromise Na+ Activation of the Na+,K+-ATPase

    PubMed Central

    Mahmmoud, Yasser A.; Kopec, Wojciech; Khandelia, Himanshu

    2015-01-01

    The Na+,K+-ATPase is essential for ionic homeostasis in animal cells. The dephosphoenzyme contains Na+ selective inward facing sites, whereas the phosphoenzyme contains K+ selective outward facing sites. Under normal physiological conditions, K+ inhibits cytoplasmic Na+ activation of the enzyme. Acetamidinium (Acet+) and formamidinium (Form+) have been shown to permeate the pump through the outward facing sites. Here, we show that these cations, unlike K+, are unable to enter the inward facing sites in the dephosphorylated enzyme. Consistently, the organic cations exhibited little to no antagonism to cytoplasmic Na+ activation. Na+,K+-ATPase structures revealed a previously undescribed rotamer transition of the hydroxymethyl side chain of the absolutely conserved Thr772 of the α-subunit. The side chain contributes its hydroxyl to Na+ in site I in the E1 form and rotates to contribute its methyl group toward K+ in the E2 form. Molecular dynamics simulations to the E1·AlF4−·ADP·3Na+ structure indicated that 1) bound organic cations differentially distorted the ion binding sites, 2) the hydroxymethyl of Thr772 rotates to stabilize bound Form+ through water molecules, and 3) the rotamer transition is mediated by water traffic into the ion binding cavity. Accordingly, dehydration induced by osmotic stress enhanced the interaction of the congeners with the outward facing sites and profoundly modified the organization of membrane domains of the α-subunit. These results assign a catalytic role for water in pump function, and shed light on a backbone-independent but a conformation-dependent switch between H-bond and dispersion contact as part of the catalytic mechanism of the Na+,K+-ATPase. PMID:25533461

  13. Na Partitioning During Thermomechanical Processing of an Mg-Sn-Zn-Na Alloy

    NASA Astrophysics Data System (ADS)

    TerBush, Jessica R.; Stanford, Nicole; Nie, Jian-Feng; Barnett, Matthew R.

    2013-11-01

    Microstructural characterization was used to examine the changes that occur in an Mg-6Sn-5Zn-0.3Na alloy from casting to extrusion at either 623 K or 723 K (350 °C or 450 °C) followed by artificial aging at 473 K (200 °C). In particular, the partitioning of Na was examined at each step using STEM-EDS mapping. Na atoms were found to preferentially partition to the Mg-Zn phase when present. After extrusion, when no Mg-Zn was observed, the spherical Mg2Sn particles were found to be enriched in Na, particularly at the higher extrusion temperature. Artificial aging following extrusion resulted in a change in Na partitioning, and a coarse distribution of Mg-Zn precipitate rods. Na microadditions led to a high as-extruded hardness, but a significant tension-compression yield asymmetry was still observed at room temperature. The compressive yield strength was found to decrease significantly after 1000 hours of aging.

  14. Conduction of Na+ and K+ through the NaK Channel: Molecular and Brownian Dynamics Studies

    PubMed Central

    Vora, Taira; Bisset, David; Chung, Shin-Ho

    2008-01-01

    Conduction of ions through the NaK channel, with M0 helix removed, was studied using both Brownian dynamics and molecular dynamics. Brownian dynamics simulations predict that the truncated NaK has approximately a third of the conductance of the related KcsA K+ channel, is outwardly rectifying, and has a Michaelis-Menten current-concentration relationship. Current magnitude increases when the glutamine residue located near the intracellular gate is replaced with a glutamate residue. The channel is blocked by extracellular Ca2+. Molecular dynamics simulations show that, under the influence of a strong applied potential, both Na+ and K+ move across the selectivity filter, although conduction rates for Na+ ions are somewhat lower. The mechanism of conduction of Na+ differs significantly from that of K+ in that Na+ is preferentially coordinated by single planes of pore-lining carbonyl oxygens, instead of two planes as in the usual K+ binding sites. The water-containing filter pocket resulting from a single change in the selectivity filter sequence (compared to potassium channels) disrupts several of the planes of carbonyl oxygens, and thus reduces the filter's ability to discriminate against sodium. PMID:18456826

  15. Conduction of Na+ and K+ through the NaK channel: molecular and Brownian dynamics studies.

    PubMed

    Vora, Taira; Bisset, David; Chung, Shin-Ho

    2008-08-01

    Conduction of ions through the NaK channel, with M0 helix removed, was studied using both Brownian dynamics and molecular dynamics. Brownian dynamics simulations predict that the truncated NaK has approximately a third of the conductance of the related KcsA K+ channel, is outwardly rectifying, and has a Michaelis-Menten current-concentration relationship. Current magnitude increases when the glutamine residue located near the intracellular gate is replaced with a glutamate residue. The channel is blocked by extracellular Ca2+. Molecular dynamics simulations show that, under the influence of a strong applied potential, both Na+ and K+ move across the selectivity filter, although conduction rates for Na+ ions are somewhat lower. The mechanism of conduction of Na+ differs significantly from that of K+ in that Na+ is preferentially coordinated by single planes of pore-lining carbonyl oxygens, instead of two planes as in the usual K+ binding sites. The water-containing filter pocket resulting from a single change in the selectivity filter sequence (compared to potassium channels) disrupts several of the planes of carbonyl oxygens, and thus reduces the filter's ability to discriminate against sodium.

  16. Na/beta-alumina/NaAlCl4, Cl2/C circulating cell

    NASA Astrophysics Data System (ADS)

    Cherng, Jing-Yih; Bennion, Douglas N.

    1987-09-01

    A study was made of a high specific energy battery based on a sodium negative electrode and a chlorine positive electrode with molten AlCl3-NaCl electrolyte and a solid beta alumina separator. The basic performance of a Na beta-alumina NaAlCl4, Cl2/C circulating cell at 200 C was demonstrated. This cell can be started at 150 C. The use of melting sodium chloroaluminate electrolyte overcomes some of the material problems associated with the high working temperatures of present molten salt systems, such as Na/S and LiAl/FeS, and retains the advantages of high energy density and relatively efficient electrode processes. Preliminary investigations were conducted on a sodium-chlorine static cell, material compability, electrode design, wetting, and theoretical calculations to assure a better chance of success before assembling a Na/Cl2 circulating cell. Mathematical models provide a theoretical explanation for the performance of the NaCl2 battery. The results of mathematical models match the experimental results very well. According to the result of the mathematical modeling, an output at 180 mA/sq cm and 3.2 V can be obtained with optimized cell design.

  17. Na+-NQR (Na+-translocating NADH:ubiquinone oxidoreductase) as a novel target for antibiotics.

    PubMed

    Dibrov, Pavel; Dibrov, Elena; Pierce, Grant N

    2017-09-01

    The recent breakthrough in structural studies on Na+-translocating NADH:ubiquinone oxidoreductase (Na+-NQR) from the human pathogen Vibrio cholerae creates a perspective for the systematic design of inhibitors for this unique enzyme, which is the major Na+ pump in aerobic pathogens. Widespread distribution of Na+-NQR among pathogenic species, its key role in energy metabolism, its relation to virulence in different species as well as its absence in eukaryotic cells makes this enzyme especially attractive as a target for prospective antibiotics. In this review, the major biochemical, physiological and, especially, the pharmacological aspects of Na+-NQR are discussed to assess its 'target potential' for drug development. A comparison to other primary bacterial Na+ pumps supports the contention that NQR is a first rate prospective target for a new generation of antimicrobials. A new, narrowly targeted furanone inhibitor of NQR designed in our group is presented as a molecular platform for the development of anti-NQR remedies. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Final-state symmetry of Na 1s core-shell excitons in NaCl and NaF

    SciTech Connect

    Nagle, K.P.; Seidler, G.T.; Shirley, E.L.; Fister, T.T.; Bradley, J.A.; Brown, F.C.

    2009-08-13

    We report measurements of the Na 1s contribution to the nonresonant inelastic x-ray scattering (NRIXS) from NaCl and NaF. Prior x-ray absorption studies have observed two pre-edge excitons in both materials. The momentum-transfer dependence (q dependence) of the measured NRIXS cross section and of real-space full multiple scattering and Bethe-Salpeter calculations determine that the higher-energy core excitons are s type for each material. The lower-energy core excitons contribute at most weakly to the NRIXS signal and we propose that these may be surface core excitons, as have been observed in several other alkali halides. The analysis of the orbital angular momentum of these features leads to a discussion of the limited sensitivity of NRIXS measurements to d-type final states when investigating 1s initial states. In this case the s- and p-type final density of states can be characterized by measurements at a small number of momentum transfers. This is in contrast to the case of more complex initial states for which measurements at a large number of momentum transfers are needed to separate the rich admixture of accessible and contributing final-state symmetries.

  19. Local Area Networks.

    ERIC Educational Resources Information Center

    Bullard, David

    1983-01-01

    The proliferation of word processors, micro- and minicomputer systems, and other digital office equipment is causing major design changes in existing networks. Local Area Networks (LANs) which have adequately served terminal users in the past must now be redesigned. Implementation at Clemson is described. (MLW)

  20. Local Area Networks.

    ERIC Educational Resources Information Center

    Marks, Kenneth E.; Nielsen, Steven

    1991-01-01

    Discusses cabling that is needed in local area networks (LANs). Types of cables that may be selected are described, including twisted pair, coaxial cables (or ethernet), and fiber optics; network topologies, the manner in which the cables are laid out, are considered; and cable installation issues are discussed. (LRW)

  1. Local Area Networks.

    ERIC Educational Resources Information Center

    Nasatir, Marilyn; And Others

    1990-01-01

    Four papers discuss LANs (local area networks) and library applications: (1) "Institute for Electrical and Electronic Engineers Standards..." (Charles D. Brown); (2) "Facilities Planning for LANs..." (Gail Persky); (3) "Growing up with the Alumni Library: LAN..." (Russell Buchanan); and (4) "Implementing a LAN...at the Health Sciences Library"…

  2. Area Handbook for Syria.

    ERIC Educational Resources Information Center

    Nyrop, Richard; And Others

    This volume on Syria is one of a series of handbooks prepared by the Foreign Area Studies (FAS) of the American University, designed to be useful to military and other personnel who need a convenient compilation of basic facts about the social, economic, political, and military institutions and practices of various countries. The emphasis is on…

  3. Plutonium focus area

    SciTech Connect

    1996-08-01

    To ensure research and development programs focus on the most pressing environmental restoration and waste management problems at the U.S. Department of Energy (DOE), the Assistant Secretary for the Office of Environmental Management (EM) established a working group in August 1993 to implement a new approach to research and technology development. As part of this new approach, EM developed a management structure and principles that led to the creation of specific Focus Areas. These organizations were designed to focus the scientific and technical talent throughout DOE and the national scientific community on the major environmental restoration and waste management problems facing DOE. The Focus Area approach provides the framework for intersite cooperation and leveraging of resources on common problems. After the original establishment of five major Focus Areas within the Office of Technology Development (EM-50, now called the Office of Science and Technology), the Nuclear Materials Stabilization Task Group (EM-66) followed the structure already in place in EM-50 and chartered the Plutonium Focus Area (PFA). The following information outlines the scope and mission of the EM, EM-60, and EM-66 organizations as related to the PFA organizational structure.

  4. SAFIS Area Estimation Techniques

    Treesearch

    Gregory A. Reams

    2000-01-01

    The Southern Annual Forest inventory System (SAFIS) is in various stages of implementation in 8 of the 13 southern states served by the Southern Research Station of the USDA Forest Service. Compared to periodic inventories, SAFIS requires more rapid generation of land use and land cover maps. The current photo system for phase one area estimation has changed little...

  5. SAFIS area estimation techniques

    Treesearch

    Gregory A. Reams

    2000-01-01

    The Southern Annual Forest Inventory System (SAFIS) is in various stages of implementation in 8 of the 13 southern states served by the Southern Research Station of the USDA Forest Service. Compared to periodic inventories, SAFIS requires more rapid generation of land use and land cover maps. The current photo system for phase one area estimation has changed little...

  6. Subsurface contaminants focus area

    SciTech Connect

    1996-08-01

    The US Department of Enregy (DOE) Subsurface Contaminants Focus Area is developing technologies to address environmental problems associated with hazardous and radioactive contaminants in soil and groundwater that exist throughout the DOE complex, including radionuclides, heavy metals; and dense non-aqueous phase liquids (DNAPLs). More than 5,700 known DOE groundwater plumes have contaminated over 600 billion gallons of water and 200 million cubic meters of soil. Migration of these plumes threatens local and regional water sources, and in some cases has already adversely impacted off-site rsources. In addition, the Subsurface Contaminants Focus Area is responsible for supplying technologies for the remediation of numerous landfills at DOE facilities. These landfills are estimated to contain over 3 million cubic meters of radioactive and hazardous buried Technology developed within this specialty area will provide efective methods to contain contaminant plumes and new or alternative technologies for development of in situ technologies to minimize waste disposal costs and potential worker exposure by treating plumes in place. While addressing contaminant plumes emanating from DOE landfills, the Subsurface Contaminants Focus Area is also working to develop new or alternative technologies for the in situ stabilization, and nonintrusive characterization of these disposal sites.

  7. Areas of Learning

    ERIC Educational Resources Information Center

    Coe, John

    2010-01-01

    This article examines the recommendations made by the Independent Review of the Primary Curriculum (the Rose Report in 2009) that the curriculum should be organised into areas of learning. The implications for teachers are considered. By drawing upon past experience some major weaknesses and strengths implicit in the approach are identified and…

  8. LOCATING AREAS OF CONCERN

    EPA Science Inventory

    A simple method to locate changes in vegetation cover, which can be used to identify areas under stress. The method only requires inexpensive NDVI data. The use of remotely sensed data is far more cost-effective than field studies and can be performed more quickly. Local knowledg...

  9. Content Area Vocabulary Learning

    ERIC Educational Resources Information Center

    Fisher, Douglas; Frey, Nancy

    2014-01-01

    Students' vocabulary knowledge is a significant predictor of their overall comprehension. The Common Core State Standards are raising the expectations for word learning and there are now 4 distinct standards related to vocabulary as well as expectations in other standards, including content areas. To address these expectations, teachers need…

  10. Saving Natural Areas.

    ERIC Educational Resources Information Center

    Buchinger, Maria

    This manual serves as a handbook for those involved in the art of land saving. The various topics in the booklet are dealt with in great detail since little has been published on the preservation of natural areas in international publications. Most of the document is derived from articles, books, and publications published by, or describing the…

  11. Local Area Networks.

    ERIC Educational Resources Information Center

    Nasatir, Marilyn; And Others

    1990-01-01

    Four papers discuss LANs (local area networks) and library applications: (1) "Institute for Electrical and Electronic Engineers Standards..." (Charles D. Brown); (2) "Facilities Planning for LANs..." (Gail Persky); (3) "Growing up with the Alumni Library: LAN..." (Russell Buchanan); and (4) "Implementing a LAN...at the Health Sciences Library"…

  12. Area Handbook for Iraq.

    ERIC Educational Resources Information Center

    Smith, Harvey H.; And Others

    This volume is one of a series of handbooks prepared by Foreign Area Studies (FAS) of The American University, designed to be useful to military and other personnel who need a convenient compilation of basic facts about the social, economic, political and military institutions and practices of various countries. This particular handbook…

  13. Area Handbook for Mozambique.

    ERIC Educational Resources Information Center

    Herrick, Allison Butler

    This publication is one of a series of handbooks prepared by the Foreign Areas Studies (FAS) of The American University, designed to be useful to military and other personnel who need a convenient compilation of basic facts about the social, economic, political and military institutions and practices of various countries. The present handbook…

  14. Area Handbook for Guatemala.

    ERIC Educational Resources Information Center

    Dombrowski, John; And Others

    This volume is one of a series of handbooks prepared by Foreign Area Studies of American University designed to be useful to military and other personnel who need a convenient compilation of basic facts about the social, economic, political, and military institutions and practices of various countries. Chapters focus on: (1) the general character…

  15. Area Handbook for Uganda.

    ERIC Educational Resources Information Center

    Herrick, Allison Butler; And Others

    One of a series of handbooks prepared by Foreign Area Studies (FAS) of The American University, this book is an attempt to provide a comprehensive study of the dominant social, political, and economic aspects of Ugandan society, to present its strengths and weaknesses, and to identify the patterns of behavior characteristics of its members.…

  16. Sensitive Small Area Photometer

    ERIC Educational Resources Information Center

    Levenson, M. D.

    1970-01-01

    Describes a simple photometer capable of measuring small light intensities over small areas. The inexpensive, easy-to- construct instrument is intended for use in a student laboratory to measure the light intensities in a diffraction experiment from single or multiple slits. Typical experimental results are presented along with the theoretical…

  17. Areas and Brownies.

    ERIC Educational Resources Information Center

    Fan, C. Kenneth

    1997-01-01

    Presents an activity that connects area with cutting brownies which are in different shapes for different numbers, uses algebraic equations, and fixes the exact dimensions of brownies. Concludes with four different solutions from six people for the class of 16 and a trapezoidal brownie. (ASK)

  18. Areas and Brownies.

    ERIC Educational Resources Information Center

    Fan, C. Kenneth

    1997-01-01

    Presents an activity that connects area with cutting brownies which are in different shapes for different numbers, uses algebraic equations, and fixes the exact dimensions of brownies. Concludes with four different solutions from six people for the class of 16 and a trapezoidal brownie. (ASK)

  19. Metropolitan area of Chicago

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The metropolitan area of Chicago is encompassed in this Skylab 3 Earth Resources Experiments Package (EREP) S190-B photograph taken on September 18, 1973 from the Skylab space station cluster in Earth orbit. The surrounding major cities of Aurora and Joliet, Illinois; Hammond, Gary and East Chicago, Indiana, are easily delineated.

  20. LOCATING AREAS OF CONCERN

    EPA Science Inventory

    A simple method to locate changes in vegetation cover, which can be used to identify areas under stress. The method only requires inexpensive NDVI data. The use of remotely sensed data is far more cost-effective than field studies and can be performed more quickly. Local knowledg...

  1. Tangrams and Area.

    ERIC Educational Resources Information Center

    Duke, Charlotte

    1998-01-01

    Presents an activity for demonstrating the area of five geometric figures--the square, the rectangle, the parallelogram, the triangle, and the trapezoid--that is based on a simple tangram puzzle. Suggests ways in which this activity can be used at several different levels. (ASK)

  2. Area Vocational Schools.

    ERIC Educational Resources Information Center

    Russo, Michael

    1966-01-01

    This description of the DeKalb Area Technical School near Clarkston, Georgia, serves as a guide on methods of developing curriculums and facilities for such schools. The classrooms, laboratories, and shops are described with photographic illustrations of the course offerings to daytime and nighttime students. The necessity to tailor vocational…

  3. Areas of Learning

    ERIC Educational Resources Information Center

    Coe, John

    2010-01-01

    This article examines the recommendations made by the Independent Review of the Primary Curriculum (the Rose Report in 2009) that the curriculum should be organised into areas of learning. The implications for teachers are considered. By drawing upon past experience some major weaknesses and strengths implicit in the approach are identified and…

  4. Local Area Networks.

    ERIC Educational Resources Information Center

    Marks, Kenneth E.; Nielsen, Steven

    1991-01-01

    Discusses cabling that is needed in local area networks (LANs). Types of cables that may be selected are described, including twisted pair, coaxial cables (or ethernet), and fiber optics; network topologies, the manner in which the cables are laid out, are considered; and cable installation issues are discussed. (LRW)

  5. Area Handbook for Afghanistan.

    ERIC Educational Resources Information Center

    Smith, Harvey H.; And Others

    This handbook is one of a series prepared by Foreign Area Studies (FAS) of The American University as a convenient compilation of basic fact for American military and other personnel overseas. It deals with the political, social, economic, and military developments since 1959, which have contributed to Afghanistan's continuing national stability…

  6. Small Area Forecast Evaluation.

    ERIC Educational Resources Information Center

    Southeast Michigan Council of Governments, Detroit.

    The results of a small area forecast with regard to household composition, population and employment distribution, development and school costs, environmental impact, and transportation in Southeast Michigan are evaluated in this report. The role of public policy in influencing the community demography by the year 2000 is considered by…

  7. Computational interpretation of 23Na MQMAS NMR spectra: A comprehensive investigation of the Na environment in silicate glasses

    NASA Astrophysics Data System (ADS)

    Gambuzzi, Elisa; Charpentier, Thibault; Menziani, Maria Cristina; Pedone, Alfonso

    2014-09-01

    Molecular dynamics, density functional theory calculations and 23Na NMR experiments have been used to inspect the chemical and structural characteristics of the Na environment in soda-lime silicate (CSN) and aluminosilicate (CASN) glasses. The use of an improved 3QMAS pulse sequence has allowed a clear identification of different Na sites. Average coordination numbers have been extracted by fitting the 23Na 3QMAS spectra with the computed NMR parameters. The results show that the 23Na δiso values correlate with the average <Na-O> distances only when the different coordination numbers are explicitly taken into account.

  8. Novel low cost chemical texturing for very large area industrial multi-crystalline silicon solar cells

    NASA Astrophysics Data System (ADS)

    Gangopadhyay, U.; Dhungel, S. K.; Kim, K.; Manna, U.; Basu, P. K.; Kim, H. J.; Karunagaran, B.; Lee, K. S.; Yoo, J. S.; Yi, J.

    2005-09-01

    Multi-crystalline silicon surface etching without grain-boundary delineation is a challenging task for the fabrication of high efficiency solar cells. The use of sodium hydroxide-sodium hypochlorite (NaOH-NaOCl) solution for texturing a multi-crystalline silicon wafer surface in a solar cell fabrication line is reported in this paper. The optimized etching solution of NaOH-NaOCl does not have any effect on multi-crystalline silicon grain boundaries and it also has excellent isotropic etch characteristics, which ultimately helps to achieve higher values of performance parameters, especially the open circuit voltage (Voc) and fill factor (FF), than those in the case of conventional silicon texturing. Easy control over the reaction of the NaOH-NaOCl solution is also one of the major advantages due to which sophistication in controlling the temperature of the etching bath is not required for the industrial batch process. The FTIR analysis of the silicon surface after etching with the current approach shows the formation of Si-Cl bonds, which improves the quality of the diffused junction due to chlorine gettering during diffusion. We are the first to report 14-14.5% efficiency of very large area (150 mm × 150 mm) multi-crystalline silicon solar cells using a NaOH-NaOCl texturing approach in an industrial production line with a yield greater than 95%.

  9. Influence of salinity on the localization of Na+/K +-ATPase, Na+/K+/2Cl- cotransporter (NKCC) and CFTR anion channel in chloride cells of the Hawaiian goby (Stenogobius hawaiiensis)

    USGS Publications Warehouse

    McCormick, S.D.; Sundell, K.; Bjornsson, Bjorn Thrandur; Brown, C.L.; Hiroi, J.

    2003-01-01

    Na+/K+-ATPase, Na+/K+/2Cl- cotransporter (NKCC) and cystic fibrosis transmembrane conductance regulator (CFTR) are the three major transport proteins thought to be involved in chloride secretion in teleost fish. If this is the case, the levels of these transporters should be high in chloride cells of seawater-acclimated fish. We therefore examined the influence of salinity on immunolocalization of Na +/K+-ATPase, NKCC and CFTR in the gills of the Hawaiian goby (Stenogobius hawaiiensis). Fish were acclimated to freshwater and 20??? and 30??? seawater for 10 days. Na+/K +-ATPase and NKCC were localized specifically to chloride cells and stained throughout most of the cell except for the nucleus and the most apical region, indicating a basolateral/tubular distribution. All Na+/K +-ATPase-positive chloride cells were also positive for NKCC in all salinities. Salinity caused a slight increase in chloride cell number and size and a slight decrease in staining intensity for Na+/K +-ATPase and NKCC, but the basic pattern of localization was not altered. Gill Na+/K+-ATPase activity was also not affected by salinity. CFTR was localized to the apical surface of chloride cells, and only cells staining positive for Na+/K+-ATPase were CFTR-positive. CFTR-positive cells greatly increased in number (5-fold), area stained (53%) and intensity (29%) after seawater acclimation. In freshwater, CFTR immunoreactivity was light and occurred over a broad apical surface on chloride cells, whereas in seawater there was intense immunoreactivity around the apical pit (which was often punctate in appearance) and a light subapical staining. The results indicate that Na+/K +-ATPase, NKCC and CFTR are all present in chloride cells and support current models that all three are responsible for chloride secretion by chloride cells of teleost fish.

  10. Influence of salinity on the localization of Na+/K+-ATPase, Na+/K+/2Cl- cotransporter (NKCC) and CFTR anion channel in chloride cells of the Hawaiian goby (Stenogobius hawaiiensis).

    PubMed

    McCormick, Stephen D; Sundell, Kristina; Björnsson, Björn Thrandur; Brown, Christopher L; Hiroi, Junya

    2003-12-01

    Na+/K+-ATPase, Na+/K+/2Cl- cotransporter (NKCC) and cystic fibrosis transmembrane conductance regulator (CFTR) are the three major transport proteins thought to be involved in chloride secretion in teleost fish. If this is the case, the levels of these transporters should be high in chloride cells of seawater-acclimated fish. We therefore examined the influence of salinity on immunolocalization of Na+/K+-ATPase, NKCC and CFTR in the gills of the Hawaiian goby (Stenogobius hawaiiensis). Fish were acclimated to freshwater and 20 per thousand and 30 per thousand seawater for 10 days. Na+/K+-ATPase and NKCC were localized specifically to chloride cells and stained throughout most of the cell except for the nucleus and the most apical region, indicating a basolateral/tubular distribution. All Na+/K+-ATPase-positive chloride cells were also positive for NKCC in all salinities. Salinity caused a slight increase in chloride cell number and size and a slight decrease in staining intensity for Na+/K+-ATPase and NKCC, but the basic pattern of localization was not altered. Gill Na+/K+-ATPase activity was also not affected by salinity. CFTR was localized to the apical surface of chloride cells, and only cells staining positive for Na+/K+-ATPase were CFTR-positive. CFTR-positive cells greatly increased in number (5-fold), area stained (53%) and intensity (29%) after seawater acclimation. In freshwater, CFTR immunoreactivity was light and occurred over a broad apical surface on chloride cells, whereas in seawater there was intense immunoreactivity around the apical pit (which was often punctate in appearance) and a light subapical staining. The results indicate that Na+/K+-ATPase, NKCC and CFTR are all present in chloride cells and support current models that all three are responsible for chloride secretion by chloride cells of teleost fish.

  11. [Analysis of the contents of elements in spirulina from different producing areas].

    PubMed

    Guan, Ying; Zhao, Hai-ying; Ding, Xi-feng; Zhu, Yan-ying

    2007-05-01

    Five samples of spirulina from different producing areas were analyzed and characterized with X-ray fluorescence analysis. The contents of K, Na, Ca, Mg, Fe, Zn and Mn in spinrulina samples from different producing areas were determined. The results show that spinrulinas are rich in microelements that human body needs. The spectra of main elements of spirulina from different producing areas are similar, but the content of each elements is different. The content of K is 5.00% averagely, the highest in the five samples, the content of Na is 0.352%, and the ratio of Na/K is 0.070 on average. The relationship between K, Na/K and medical care efficiency was studied. Lesser value of Na/K is helpful to hypertension patients. It was suggested that hypertension patients should take in less Na, but more K. This can help prevent and cure hypertension. The method proves to be simple, rapid, accurate, and highly sensitive, and can be used for simultaneous multielement determination. The authors' study provides a new scientific foundation for further study and general application of spirulina.

  12. An enhancement to the NA4 gear vibration diagnostic parameter

    NASA Technical Reports Server (NTRS)

    Decker, Harry J.; Handschuh, Robert F.; Zakrajsek, James J.

    1994-01-01

    A new vibration diagnostic parameter for health monitoring of gears, NA4*, is proposed and tested. A recently developed gear vibration diagnostic parameter NA4 outperformed other fault detection methods at indicating the start and initial progression of damage. However, in some cases, as the damage progressed, the sensitivity of the NA4 and FM4 parameters tended to decrease and no longer indicated damage. A new parameter, NA4* was developed by enhancing NA4 to improve the trending of the parameter. This allows for the indication of damage both at initiation and also as the damage progresses. The NA4* parameter was verified and compared to the NA4 and FM4 parameters using experimental data from single mesh spur and spiral bevel gear fatigue rigs. The primary failure mode for the test cases was naturally occurring tooth surface pitting. The NA4* parameter is shown to be a more robust indicator of damage.

  13. Mechanisms and regulation of Na(+) uptake by freshwater fish.

    PubMed

    Kumai, Yusuke; Perry, Steve F

    2012-12-01

    Mechanisms of ion uptake by freshwater (FW) fish have received considerable attention over the past 80 years. Through an assortment of techniques incorporating whole animal physiology, electrophysiology and molecular biological approaches, three models have been proposed to account for Na(+) uptake. (1) Direct exchange of Na(+) and H(+) via one or more types of Na(+)/H(+) exchanger (slc9), (2) uptake of Na(+) through epithelial Na(+) channels energized by an electrical gradient created by H(+)-ATPase and (3) Na(+)/Cl(-) co-transport (slc12). While each mechanism is supported at least in part by theoretical or experimental data, there are several outstanding questions that have not yet been fully resolved. Furthermore, there are few details concerning how these Na(+) uptake mechanisms are fine tuned in response to the fluctuating FW environments. In this review, we summarize the current understanding of these three Na(+) uptake mechanisms and discuss their regulation by endocrine (cortisol and prolactin) and neurohumoral (catecholamines) factors.

  14. U. S. EPA’S NA APPROACH FOR PETROLEUM HYDROCARBONS

    EPA Science Inventory

    Most evaluations of NA of petroleum hydrocarbons use geochemical data to document the NA through biodegradation. The expected trends during biodegradation (plume interior vs. background concentrations) are Dissolved oxygen concentrations below background, Nitrate concentrations ...

  15. U. S. EPA’S NA APPROACH FOR PETROLEUM HYDROCARBONS

    EPA Science Inventory

    Most evaluations of NA of petroleum hydrocarbons use geochemical data to document the NA through biodegradation. The expected trends during biodegradation (plume interior vs. background concentrations) are Dissolved oxygen concentrations below background, Nitrate concentrations ...

  16. Inelastic and reactive collisions with polarized excited Na atoms

    SciTech Connect

    Schmidt, H.; Hertel, I.V.; Lee, Y.T.

    1985-07-01

    Polarization effects in inelastic collisions of laser state-prepared Na(3/sup 2/P, M/sub J/) with Na/sup +/ leading to Na(3/sup 2/D) or Na(3/sup 2/S) are discussed for the energy range E/sub cm/ = 5-47.5eV. Studies with linearly polarized light can be explained with a simple ''locking'' model of the Na(P)-orbital. The investigations employing circularly polarized light are a very sensitive test of the models describing the nonadiabatic angular momentum coupling between electronic and nuclear motion. The dynamical effects of the electronic spin on the angular momentum transfer are discussed. Recent crossed-beam experiments on the Na + O/sub 2/ -> NaO = O reaction in the energy range E/sub cm/ = 0/3-0.8eV show a pronounced dependence on the electric electronic symmetry of Na. 17 refs., 11 figs.

  17. Elementary immunology: Na(+) as a regulator of immunity.

    PubMed

    Schatz, Valentin; Neubert, Patrick; Schröder, Agnes; Binger, Katrina; Gebhard, Matthias; Müller, Dominik N; Luft, Friedrich C; Titze, Jens; Jantsch, Jonathan

    2017-02-01

    The skin can serve as an interstitial Na(+) reservoir. Local tissue Na(+) accumulation increases with age, inflammation and infection. This increased local Na(+) availability favors pro-inflammatory immune cell function and dampens their anti-inflammatory capacity. In this review, we summarize available data on how NaCl affects various immune cells. We particularly focus on how salt promotes pro-inflammatory macrophage and T cell function and simultaneously curtails their regulatory and anti-inflammatory potential. Overall, these findings demonstrate that local Na(+) availability is a promising novel regulator of immunity. Hence, the modulation of tissue Na(+) levels bears broad therapeutic potential: increasing local Na(+) availability may help in treating infections, while lowering tissue Na(+) levels may be used to treat, for example, autoimmune and cardiovascular diseases.

  18. Design of Na(+) -Selective Fluorescent Probes: A Systematic Study of the Na(+) -Complex Stability and the Na(+) /K(+) Selectivity in Acetonitrile and Water.

    PubMed

    Schwarze, Thomas; Müller, Holger; Schmidt, Darya; Riemer, Janine; Holdt, Hans-Jürgen

    2017-05-29

    There is a tremendous demand for highly Na(+) -selective fluoroionophores to monitor the top analyte Na(+) in life science. Here, we report a systematic route to develop highly Na(+) /K(+) selective fluorescent probes. Thus, we synthesized a set of fluoroionophores 1, 3, 4, 5, 8 and 9 (see Scheme ) to investigate the Na(+) /K(+) selectivity and Na(+) - complex stability in CH3 CN and H2 O. These Na(+) -probes bear different 15-crown-5 moieties to bind Na(+) stronger than K(+) . In the set of the diethylaminocoumarin-substituted fluoroionophores 1-5, the following trend of fluorescence quenching 1>3>2>4>5 in CH3 CN was observed. Therefore, the flexibility of the aza-15-crown-5 moieties in 1-4 determines the conjugation of the nitrogen lone pair with the aromatic ring. As a consequence, 1 showed in CH3 CN the highest Na(+) -induced fluorescence enhancement (FE) by a factor of 46.5 and a weaker K(+) induced FE of 3.7. The Na(+) -complex stability of 1-4 in CH3 CN is enhanced in the following order of 2>4>3>1, assuming that the O-atom of the methoxy group in the ortho-position, as shown in 2, strengthened the Na(+) -complex formation. Furthermore, we found for the N-(o-methoxyphenyl)aza-15-crown-5 substituted fluoroionophores 2, 8 and 9 in H2 O, an enhanced Na(+) -complex stability in the following order 8>2>9 and an increased Na(+) /K(+) selectivity in the reverse order 9>2>8. Notably, the Na(+) -induced FE of 8 (FEF=10.9), 2 (FEF=5.0) and 9 (FEF=2.0) showed a similar trend associated with a decreased K(+) -induced FE [8 (FEF=2.7)>2 (FEF=1.5)>9 (FEF=1.1)]. Here, the Na(+) -complex stability and Na(+) /K(+) selectivity is also influenced by the fluorophore moiety. Thus, fluorescent probe 8 (Kd =48 mm) allows high-contrast, sensitive, and selective Na(+) measurements over extracellular K(+) levels. A higher Na(+) /K(+) selectivity showed fluorescent probe 9, but also a higher Kd value of 223 mm. Therefore, 9 is a suitable tool to measure Na(+) concentrations up to

  19. Na+ deposition in the fibrotic skin of systemic sclerosis patients detected by 23Na-magnetic resonance imaging.

    PubMed

    Kopp, Christoph; Beyer, Christian; Linz, Peter; Dahlmann, Anke; Hammon, Matthias; Jantsch, Jonathan; Neubert, Patrick; Rosenhauer, Daniela; Müller, Dominik N; Cavallaro, Alexander; Eckardt, Kai-Uwe; Schett, Georg; Luft, Friedrich C; Uder, Michael; Distler, Jörg H W; Titze, Jens

    2017-04-01

    Skin fibrosis is the predominant feature of SSc and arises from excessive extracellular matrix deposition. Glycosaminoglycans are macromolecules of the extracellular matrix, which facilitate Na + accumulation in the skin. We used 23 Na-MRI to quantify Na + in skin. We hypothesized that skin Na + might accumulate in SSc and might be a biomarker for skin fibrosis. In this observational case-control study, skin Na + was determined by 23 Na-MRI using a Na + volume coil in 12 patients with diffuse cutaneous SSc and in 21 control subjects. We assessed skin fibrosis by the modified Rodnan skin score prior to 23 Na-MRI and on follow-up 12 months later. 23 Na-MRI demonstrated increased Na + in the fibrotic skin of SSc patients compared with skin from controls [mean ( s . d .): 27.2 (5.6) vs 21.4 (5.3) mmol/l, P < 0.01]. Na + content was higher in fibrotic than in non-fibrotic SSc skin [26.2 (4.8) vs 19.2 (3.4) mmol/l, P < 0.01]. Furthermore, skin Na + amount was correlated with changes in follow-up modified Rodnan skin score (R 2 = 0.68). 23 Na-MRI detected increased Na + in the fibrotic SSc skin; high Na + content was associated with progressive skin disease. Our findings provide the first evidence that 23 Na-MRI might be a promising tool to assess skin Na + and thereby predict progression of skin fibrosis in SSc.

  20. Na+-driven bacterial flagellar motors.

    PubMed

    Imae, Y; Atsumi, T

    1989-12-01

    Bacterial flagellar motors are the reversible rotary engine which propels the cell by rotating a helical flagellar filament as a screw propeller. The motors are embedded in the cytoplasmic membrane, and the energy for rotation is supplied by the electrochemical potential of specific ions across the membrane. Thus, the analysis of motor rotation at the molecular level is linked to an understanding of how the living system converts chemical energy into mechanical work. Based on the coupling ions, the motors are divided into two types; one is the H+-driven type found in neutrophiles such as Bacillus subtilis and Escherichia coli and the other is the Na+-driven type found in alkalophilic Bacillus and marine Vibrio. In this review, we summarize the current status of research on the rotation mechanism of the Na+-driven flagellar motors, which introduces several new aspects in the analysis.

  1. {beta} decay of {sup 32}Na

    SciTech Connect

    Mattoon, C. M.; Sarazin, F.; Hackman, G.; Ball, G. C.; Chakrawarthy, R. S.; Scraggs, H. C.; Smith, M. B.; Cunningham, E. S.; Walker, P. M.; Austin, R. A. E.; Finlay, P.; Grinyer, G. F.; Hyland, B.; Phillips, A. A.; Schumaker, M. A.; Svensson, C. E.; Garrett, P. E.; Koopmans, K. A.; Waddington, J. C.; Washbrook, B.

    2007-01-15

    The {beta}-decay of {sup 32}Na has been studied using {beta}-{gamma} coincidences. New transitions and levels are tentatively placed in the level scheme of {sup 32}Mg from an analysis of {gamma}-{gamma} and {beta}-{gamma}-{gamma} coincidences. The observation of the indirect feeding of the 2321 keV state in {sup 32}Mg removes some restrictions previously placed on the spin assignment for this state. No evidence of a state at 2117 keV in {sup 32}Mg is found. Previously unobserved weak transitions up to 5.4 MeV were recorded but could not be placed in the decay scheme of {sup 32}Na.

  2. [Tui-Na, an oriental massage].

    PubMed

    Esteve Torres, Andreu

    2005-05-01

    Tui-Na is an oriental massage whose principles are based on traditional Chinese medicine. This medicine conceives a person as one entire entity giving as much importance to emotional and physical aspects as to everything that surrounds a person, including climate, social relationships, diet. This philosophy believes that an individual will achieve his/her ideal health state when he/she has found interior harmony and is in balance with all his/her environment. From this viewpoint, this philosophy understands pathology as an unbalance or a lack of harmony in an organism. Tui-Na massage is one of the techniques which make use of traditional Chinese medicine to maintain, or to recuperate, an organism's balance.

  3. Dielectronic recombination resonances in Na8+

    NASA Astrophysics Data System (ADS)

    Nikolić, D.; Lindroth, E.; Kieslich, S.; Brandau, C.; Schippers, S.; Shi, W.; Müller, A.; Gwinner, G.; Schnell, M.; Wolf, A.

    2004-12-01

    The electron-ion recombination spectrum of the Li-like Na8+ ion in the energy range 0.0-0.5eV is presented. Experimental results obtained by storage-ring techniques are compared with a calculated spectrum, based on a combination of relativistic many-body methods and complex rotation, and the agreement is found to be very good. The deviations between measured and calculated dielectronic recombination resonance energies are usually below about 2meV with a maximum difference at 5.5meV , while the theoretical cross sections deviate by at most 20% from the experiment. The recombination spectrum in the investigated energy region is determined by the 2pj7ℓj' Rydberg manifold of dielectronic recombination resonances, comprising 61 states within half an eV above the ground state of Na8+ . The theoretical resonance parameters of all contributing states are provided.

  4. The two C-terminal tyrosines stabilize occluded Na/K pump conformations containing Na or K ions.

    PubMed

    Vedovato, Natascia; Gadsby, David C

    2010-07-01

    Interactions of the three transported Na ions with the Na/K pump remain incompletely understood. Na/K pump crystal structures show that the extended C terminus of the Na,K-adenosine triphosphatase (ATPase) alpha subunit directly contacts transmembrane helices. Deletion of the last five residues (KETYY in almost all Na/K pumps) markedly lowered the apparent affinity for Na activation of pump phosphorylation from ATP, a reflection of cytoplasmic Na affinity for forming the occluded E1P(Na3) conformation. ATPase assays further suggested that C-terminal truncations also interfere with low affinity Na interactions, which are attributable to extracellular effects. Because extracellular Na ions traverse part of the membrane's electric field to reach their binding sites in the Na/K pump, their movements generate currents that can be monitored with high resolution. We report here electrical measurements to examine how Na/K pump interactions with extracellular Na ions are influenced by C-terminal truncations. We deleted the last two (YY) or five (KESYY) residues in Xenopus laevis alpha1 Na/K pumps made ouabain resistant by either of two kinds of point mutations and measured their currents as 10-mM ouabain-sensitive currents in Xenopus oocytes after silencing endogenous Xenopus Na/K pumps with 1 microM ouabain. We found the low affinity inhibitory influence of extracellular Na on outward Na/K pump current at negative voltages to be impaired in all of the C-terminally truncated pumps. Correspondingly, voltage jump-induced transient charge movements that reflect pump interactions with extracellular Na ions were strongly shifted to more negative potentials; this signals a several-fold reduction of the apparent affinity for extracellular Na in the truncated pumps. Parallel lowering of Na affinity on both sides of the membrane argues that the C-terminal contacts provide important stabilization of the occluded E1P(Na3) conformation, regardless of the route of Na ion entry into the

  5. The two C-terminal tyrosines stabilize occluded Na/K pump conformations containing Na or K ions

    PubMed Central

    Vedovato, Natascia

    2010-01-01

    Interactions of the three transported Na ions with the Na/K pump remain incompletely understood. Na/K pump crystal structures show that the extended C terminus of the Na,K–adenosine triphosphatase (ATPase) α subunit directly contacts transmembrane helices. Deletion of the last five residues (KETYY in almost all Na/K pumps) markedly lowered the apparent affinity for Na activation of pump phosphorylation from ATP, a reflection of cytoplasmic Na affinity for forming the occluded E1P(Na3) conformation. ATPase assays further suggested that C-terminal truncations also interfere with low affinity Na interactions, which are attributable to extracellular effects. Because extracellular Na ions traverse part of the membrane’s electric field to reach their binding sites in the Na/K pump, their movements generate currents that can be monitored with high resolution. We report here electrical measurements to examine how Na/K pump interactions with extracellular Na ions are influenced by C-terminal truncations. We deleted the last two (YY) or five (KESYY) residues in Xenopus laevis α1 Na/K pumps made ouabain resistant by either of two kinds of point mutations and measured their currents as 10-mM ouabain–sensitive currents in Xenopus oocytes after silencing endogenous Xenopus Na/K pumps with 1 µM ouabain. We found the low affinity inhibitory influence of extracellular Na on outward Na/K pump current at negative voltages to be impaired in all of the C-terminally truncated pumps. Correspondingly, voltage jump–induced transient charge movements that reflect pump interactions with extracellular Na ions were strongly shifted to more negative potentials; this signals a several-fold reduction of the apparent affinity for extracellular Na in the truncated pumps. Parallel lowering of Na affinity on both sides of the membrane argues that the C-terminal contacts provide important stabilization of the occluded E1P(Na3) conformation, regardless of the route of Na ion entry into the

  6. Informal Progress Report Contract Number: DE-FG03-02NA00074/A000

    SciTech Connect

    Carl R. Brune; Steven M. Grimes

    2003-10-10

    OAK B127 We report on work performed under contract DE-FG03-03NA00074 since January 1,2003. The research is in the area of low energy nuclear reactions and nuclear structure. The progress on research on level densities and improvement to R-Matrix calculations are presented. The preparations to begin high resolution experiments on p-shell nuclei are reviewed.

  7. Transition-Metal Additives For Long-Life Na/NiCI(2) Cells

    NASA Technical Reports Server (NTRS)

    Bugga, Ratnakumar V.; Surampudi, Subbarao; Halpert, Gerald

    1995-01-01

    Transition-metal additives in cathodes of Na/NiCI(2) high-temperature, rechargeable electrochemical cells found to slow premature fading of charge/discharge capacity. Decline in capacity of cell attributed to agglomeration of Ni particles at cathode: this agglomeration reduces electrochemical area of cathode. Depending on choice of transition-metal additive for particular cell, additive might even participate in desired electrochemical reactions in cell, contributing to specific energy of cell.

  8. The temperature dependence of the cross section for the energy pooling process Na(3P)+Na(3P) to Na(4D)+Na(3S)

    NASA Astrophysics Data System (ADS)

    Horvatic, V.; Movre, M.; Vadla, C.

    1999-10-01

    We report the measurements of the temperature dependence of the cross section σ4D for the energy pooling process Na(3P)+Na(3P) to Na(4D)+Na(3S). The latest two, as yet undisputed, results for σ4D obtained by different authors at T = 597 K and T = 483 K suggest that this cross section decreases with increasing T, which contradicts the theory and other experiments on similar processes. To resolve this controversy and to examine the temperature trend of the cross section, we have measured the σ4D in the temperature range 567-705 K, covering the high-temperature region that has not yet been investigated experimentally. To determine σ4D we have excited sodium atoms in the quasistatic wing of the D1 line using a cw dye laser and measured the fluorescence intensity for the 4D to 3P3/2 transition, relative to the intensity of the optically thin quasistatic wing of the D2 line. The spatial distribution of the number density of the sodium atoms in the 3P3/2 state and the sodium ground-state number density were measured too. The method used for the determination of the cross section is advantageous since it entirely circumvents the need to account for the radiation trapping of 3P level radiation, which was substantial under experimental conditions of the ground-state densities being 1014-1016 cm-3. The measurements of the cross section σ4D in the investigated temperature range have shown that it increases as ~exp(-Δ E/kT). From the experiment we obtained Δ E = (608±95) cm-1, which is in excellent agreement with the energy defect (613 cm-1) for the considered process, and in fair agreement with the values which follow from recent theoretical calculations.

  9. The complex lightcurve of 1992 NA

    NASA Astrophysics Data System (ADS)

    Wisniewski, Wieslaw Z.; Harris, A. W.

    1994-04-01

    Amor asteroid 1992 NA was monitored during three nights at a large phase angle of -65 deg. The lightcurves obtained did not reveal a repeatable curve with two maxima and two minima. However, some features suggested a periodicity with three maxima and three minima. A satisfactory composite lightcurve of this form was obtained by means of an 'eyeball' fit and by Fourier analysis. Individual and composite lightcurves are presented. The observed colors are consistent with the C class.

  10. The NA62 experiment at CERN

    NASA Astrophysics Data System (ADS)

    Venditti, Stefano

    2016-12-01

    The goal of the NA62 experiment at CERN is to collect O(100) events of the ultrarare K+→ π +ν bar {ν } decay in two years. After a long R&D phase and a successful pilot run in 2014, the first data-taking phase took place in 2015. In this paper the importance of the experiment's physics goal, as well as the experimental solutions adopted in order to attain it, will be reviewed.

  11. The complex lightcurve of 1992 NA

    NASA Technical Reports Server (NTRS)

    Wisniewski, Wieslaw Z.; Harris, A. W.

    1994-01-01

    Amor asteroid 1992 NA was monitored during three nights at a large phase angle of -65 deg. The lightcurves obtained did not reveal a repeatable curve with two maxima and two minima. However, some features suggested a periodicity with three maxima and three minima. A satisfactory composite lightcurve of this form was obtained by means of an 'eyeball' fit and by Fourier analysis. Individual and composite lightcurves are presented. The observed colors are consistent with the C class.

  12. Conformational changes couple Na+ and glucose transport

    PubMed Central

    Loo, Donald D. F.; Hirayama, Bruce A.; Gallardo, Elsa M.; Lam, Jason T.; Turk, Eric; Wright, Ernest M.

    1998-01-01

    The mechanism by which cotransport proteins couple their substrates across cell membranes is not known. A commonly proposed model is that cotransport results from ligand-induced conformational transitions that change the accessibility of ligand-binding sites from one side of the membrane to the other. To test this model, we have measured the accessibility of covalent probes to a cysteine residue (Q457C) placed in the putative sugar-translocation domain of the Na+/glucose cotransporter (SGLT1). The mutant protein Q457C was able to transport sugar, but transport was abolished after alkylation by methanethiosulfonate reagents. Alkylation blocked sugar translocation but not sugar binding. Accessibility of Q457C to alkylating reagents required external Na+ and was blocked by external sugar and phlorizin. The voltage dependence of accessibility was directly correlated with the presteady–state charge movement of SGLT1. Voltage-jump experiments with rhodamine-6-maleimide-labeled Q457C showed that the time course and level of changes in fluorescence closely followed the presteady–state charge movement. We conclude that conformational changes are responsible for the coupling of Na+ and sugar transport and that Q457 plays a critical role in sugar translocation by SGLT1. PMID:9636229

  13. NASA's Hypersonic Investment Area

    NASA Technical Reports Server (NTRS)

    Hueter, Uwe; Hutt, John; McClinton, Charles

    2002-01-01

    NASA has established long term goals for access to space. The third generation launch systems are to be fully reusable and operational around 2025. The goal for third-generation launch systems represents significant reduction in cost and improved safety over the current first generation system. The Advanced Space Transportation Office (ASTP) at NASA s Marshall Space Flight Center (MSFC) has the agency lead to develop space transportation technologies. Within ASTP, under the Hypersonic Investment Area (HIA), third generation technologies are being pursued in the areas of propulsion, airframe, integrated vehicle health management (IVHM), avionics, power, operations and system analysis. These technologies are being matured through research and both ground and flight-testing. This paper provides an overview of the HIA program plans and recent accomplishments.

  14. NASA's Hypersonic Investment Area

    NASA Technical Reports Server (NTRS)

    Hueter, Uwe; Hutt, John; McClinton, Charles

    2002-01-01

    NASA has established long term goals for access to space. The third generation launch systems are to be fully reusable and operational around 2025. The goal for third-generation launch systems represents significant reduction in cost and improved safety over the current first generation system. The Advanced Space Transportation Office (ASTP) at NASA s Marshall Space Flight Center (MSFC) has the agency lead to develop space transportation technologies. Within ASTP, under the Hypersonic Investment Area (HIA), third generation technologies are being pursued in the areas of propulsion, airframe, integrated vehicle health management (IVHM), avionics, power, operations and system analysis. These technologies are being matured through research and both ground and flight-testing. This paper provides an overview of the HIA program plans and recent accomplishments.

  15. Large area mass analyzer

    NASA Astrophysics Data System (ADS)

    Rachev, Mikhail; Srama, Ralf; Srowig, Andre; Grün, Eberhard

    2004-12-01

    A new time-of-flight spectrometer for the chemical analysis of cosmic dust particles in space has been simulated by Simion 7.0. The instrument is based upon impact ionization. This method is a reliable method for in situ dust detection and is well established. Instruments using the impact ionization flew on board of Helios and Galileo and are still in operation on board of the Ulysses and Cassini-Huygens missions. The new instrument has a large sensitive area of 0.1 m2 in order to achieve a significant number of measurements. The mass resolution M/ΔM>100 and the mass range covers the most relevant elements expected in cosmic dust. The instrument has a reflectron configuration which increases the mass resolution. Most of the ions released during the impact are focused to the detector. The ion detector consists of a large area ion-to-electron converter, an electron reflectron and a microchannel plate detector.

  16. Management: Area Support Responsibilities

    DTIC Science & Technology

    2007-11-02

    Georgia: All counties north of Bleckley, Bryan, Dodge, Effingham, Evans, Jones, Lamarr, Meriwether , Monroe, Montgomery, Pike, Tattnall, Telfair, Troup...the actual cost of materials). b. Area of responsibility. Table C–2 provides installation taskings by installation, State, and county . These taskings...responsibility Devens RFTA FORSCOM CT: All counties ME: All counties MA: All counties NH: All counties RI: All counties VT: All counties Fort Belvoir, VA

  17. Acoustics Local Area Network

    DTIC Science & Technology

    2013-01-31

    contract was to provide a shared computing i : resource - the acou tics local area network (ALAN) - to support ocean acoustic and related oceanographic...SECURITY CLASSIFICATION 20. UMITATION OF ABSTRACT OF REPORT: THIS PAGE OF ABSTRACT Unclassified I I ONRCtI COMPUTER V 10 11/94 STANDARD FORM 233 (REV 241) oo 0 90 " VLNV1LV HNO Og6OuLtOI, CT:tT 96/OT/0

  18. Belize Area Study

    DTIC Science & Technology

    1983-11-20

    and reported. Dental disease is rather prevalent affecting 90% of the pcpulation and is primarily treated by extractions . Nutrition Energy-protein...of problems, one of which is smut disease. Since its outbreak in 1978, smut infestation has spread to all cane growing areas. Smut-resistant seeds ...2-;.--;. *: ~ - **.;.1 scope for the promotion and expansion of production of such tree crops as coconuts and avocados . The former has the potential

  19. Glial Na(+) -dependent ion transporters in pathophysiological conditions.

    PubMed

    Boscia, Francesca; Begum, Gulnaz; Pignataro, Giuseppe; Sirabella, Rossana; Cuomo, Ornella; Casamassa, Antonella; Sun, Dandan; Annunziato, Lucio

    2016-10-01

    Sodium dynamics are essential for regulating functional processes in glial cells. Indeed, glial Na(+) signaling influences and regulates important glial activities, and plays a role in neuron-glia interaction under physiological conditions or in response to injury of the central nervous system (CNS). Emerging studies indicate that Na(+) pumps and Na(+) -dependent ion transporters in astrocytes, microglia, and oligodendrocytes regulate Na(+) homeostasis and play a fundamental role in modulating glial activities in neurological diseases. In this review, we first briefly introduced the emerging roles of each glial cell type in the pathophysiology of cerebral ischemia, Alzheimer's disease, epilepsy, Parkinson's disease, Amyotrophic Lateral Sclerosis, and myelin diseases. Then, we discussed the current knowledge on the main roles played by the different glial Na(+) -dependent ion transporters, including Na(+) /K(+) ATPase, Na(+) /Ca(2+) exchangers, Na(+) /H(+) exchangers, Na(+) -K(+) -Cl(-) cotransporters, and Na(+) - HCO3- cotransporter in the pathophysiology of the diverse CNS diseases. We highlighted their contributions in cell survival, synaptic pathology, gliotransmission, pH homeostasis, and their role in glial activation, migration, gliosis, inflammation, and tissue repair processes. Therefore, this review summarizes the foundation work for targeting Na(+) -dependent ion transporters in glia as a novel strategy to control important glial activities associated with Na(+) dynamics in different neurological disorders. GLIA 2016;64:1677-1697. © 2016 Wiley Periodicals, Inc.

  20. 33 CFR 147.833 - Na Kika FDS safety zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Na Kika FDS safety zone. 147.833 Section 147.833 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.833 Na Kika FDS safety zone. (a) Description. Na...

  1. 33 CFR 147.833 - Na Kika FDS safety zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Na Kika FDS safety zone. 147.833 Section 147.833 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.833 Na Kika FDS safety zone. (a) Description. Na...

  2. 33 CFR 147.833 - Na Kika FDS safety zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Na Kika FDS safety zone. 147.833 Section 147.833 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.833 Na Kika FDS safety zone. (a) Description. Na...

  3. 33 CFR 147.833 - Na Kika FDS safety zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Na Kika FDS safety zone. 147.833 Section 147.833 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.833 Na Kika FDS safety zone. (a) Description. Na...

  4. 33 CFR 147.833 - Na Kika FDS safety zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Na Kika FDS safety zone. 147.833 Section 147.833 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.833 Na Kika FDS safety zone. (a) Description. Na...

  5. Spontaneous NA+ transients in individual mitochondria of intact astrocytes.

    PubMed

    Azarias, Guillaume; Van de Ville, Dimitri; Unser, Michael; Chatton, Jean-Yves

    2008-02-01

    Mitochondria in intact cells maintain low Na(+) levels despite the large electrochemical gradient favoring cation influx into the matrix. In addition, they display individual spontaneous transient depolarizations. The authors report here that individual mitochondria in living astrocytes exhibit spontaneous increases in their Na(+) concentration (Na(mit)(+) spiking), as measured using the mitochondrial probe CoroNa Red. In a field of view with approximately 30 astrocytes, up to 1,400 transients per minute were typically detected under resting conditions. Na(mit)(+) spiking was also observed in neurons, but was scarce in two nonneural cell types tested. Astrocytic Na(mit)(+) spikes averaged 12.2 +/- 0.8 s in duration and 35.5 +/- 3.2 mM in amplitude and coincided with brief mitochondrial depolarizations; they were impaired by mitochondrial depolarization and ruthenium red pointing to the involvement of a cation uniporter. Na(mit)(+) spiking activity was significantly inhibited by mitochondrial Na(+)/H(+) exchanger inhibition and sensitive to cellular pH and Na(+) concentration. Ca(2+) played a permissive role on Na(mit)(+) spiking activity. Finally, the authors present evidence suggesting that Na(mit)(+) spiking frequency was correlated with cellular ATP levels. This study shows that, under physiological conditions, individual mitochondria in living astrocytes exhibit fast Na(+) exchange across their inner membrane, which reveals a new form of highly dynamic and localized functional regulation.

  6. Frostbites in circumpolar areas

    PubMed Central

    Ikäheimo, Tiina Maria; Hassi, Juhani

    2011-01-01

    Circumpolar areas are associated with prolonged cold exposure where wind, precipitation, and darkness further aggravate the environmental conditions and the associated risks. Despite the climate warming, cold climatic conditions will prevail in circumpolar areas and contribute to adverse health effects. Frostbite is a freezing injury where localized damage affects the skin and other tissues. It occurs during occupational or leisure-time activities and is common in the general population among men and women of various ages. Industries of the circumpolar areas where frostbite occurs frequently include transportation, mining, oil, and gas industry, construction, agriculture, and military operations. Cold injuries may also occur during leisure-time activities involving substantial cold exposure, such as mountaineering, skiing, and snowmobiling. Accidental situations (occupational, leisure time) often contribute to adverse cooling and cold injuries. Several environmental (temperature, wind, wetness, cold objects, and altitude) and individual (behavior, health, and physiology) predisposing factors are connected with frostbite injuries. Vulnerable populations include those having a chronic disease (cardiovascular, diabetes, and depression), children and the elderly, or homeless people. Frostbite results in sequelae causing different types of discomfort and functional limitations that may persist for years. A frostbite injury is preventable, and hence, unacceptable from a public health perspective. Appropriate cold risk management includes awareness of the adverse effects of cold, individual adjustment of cold exposure and clothing, or in occupational context different organizational and technical measures. In addition, vulnerable population groups need customized information and care for proper prevention of frostbites. PMID:21994485

  7. Vehicular road influence areas

    NASA Astrophysics Data System (ADS)

    Huertas, María E.; Huertas, José I.; Valencia, Alexander

    2017-02-01

    Vehicle operation over paved and unpaved roads is an emission source that significantly contributes to air pollution. Emissions are derived from vehicle exhaust pipes and re-suspension of particulate matter generated by wind erosion and tire to road surface interactions. Environmental authorities require a methodology to evaluate road impact areas, which enable managers to initiate counter-measures, particularly under circumstances where historic meteorological and/or air quality data is unavailable. The present study describes an analytical and experimental work developed to establish a simplified methodology to estimate the area influenced by vehicular roads. AERMOD was chosen to model pollutant dispersion generated by two roads of common attributes (straight road over flat terrain) under the effects of several arbitrary chosen weather conditions. The resulting pollutant concentration vs. Distance curves collapsed into a single curve when concentration and distance were expressed as dimensionless numbers and this curve can be described by a beta distribution function. This result implied that average concentration at a given distance was proportional to emission intensity and that it showed minor sensitivity to meteorological conditions. Therefore, road influence was defined by the area adjacent to the road limited by distance at which the beta distribution function equaled the limiting value specified by the national air quality standard for the pollutant under consideration.

  8. Frostbites in circumpolar areas.

    PubMed

    Ikäheimo, Tiina Maria; Hassi, Juhani

    2011-01-01

    Circumpolar areas are associated with prolonged cold exposure where wind, precipitation, and darkness further aggravate the environmental conditions and the associated risks. Despite the climate warming, cold climatic conditions will prevail in circumpolar areas and contribute to adverse health effects. Frostbite is a freezing injury where localized damage affects the skin and other tissues. It occurs during occupational or leisure-time activities and is common in the general population among men and women of various ages. Industries of the circumpolar areas where frostbite occurs frequently include transportation, mining, oil, and gas industry, construction, agriculture, and military operations. Cold injuries may also occur during leisure-time activities involving substantial cold exposure, such as mountaineering, skiing, and snowmobiling. Accidental situations (occupational, leisure time) often contribute to adverse cooling and cold injuries. Several environmental (temperature, wind, wetness, cold objects, and altitude) and individual (behavior, health, and physiology) predisposing factors are connected with frostbite injuries. Vulnerable populations include those having a chronic disease (cardiovascular, diabetes, and depression), children and the elderly, or homeless people. Frostbite results in sequelae causing different types of discomfort and functional limitations that may persist for years. A frostbite injury is preventable, and hence, unacceptable from a public health perspective. Appropriate cold risk management includes awareness of the adverse effects of cold, individual adjustment of cold exposure and clothing, or in occupational context different organizational and technical measures. In addition, vulnerable population groups need customized information and care for proper prevention of frostbites.

  9. High surface area calcite

    NASA Astrophysics Data System (ADS)

    Schultz, L. N.; Andersson, M. P.; Dalby, K. N.; Müter, D.; Okhrimenko, D. V.; Fordsmand, H.; Stipp, S. L. S.

    2013-05-01

    Calcite (CaCO3) is important in many fields—in nature, because it is a component of aquifers, oil reservoirs and prospective CO2 storage sites, and in industry, where it is used in products as diverse as paper, toothpaste, paint, plastic and aspirin. It is difficult to obtain high purity calcite with a high surface area but such material is necessary for industrial applications and for fundamental calcite research. Commercial powder is nearly always contaminated with growth inhibitors such as sugars, citrate or pectin and most laboratory synthesis methods deliver large precipitates, often containing vaterite or aragonite. To address this problem, we (i) adapted the method of carbonating a Ca(OH)2 slurry with CO2 gas to develop the first simple, cheap, safe and reproducible procedure using common laboratory equipment, to obtain calcite that reproducibly had a surface area of 14-17 m2/g and (ii) conducted a thorough characterization of the product. Scanning electron microscopy (SEM) revealed nanometer scale, rhombohedral crystals. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy (IR) confirmed highly crystalline, pure calcite that more closely resembles the dimensions of the biogenic calcite produced by algae in coccoliths than other methods for synthesizing calcite. We suggest that this calcite is useful when purity and high surface area are important.

  10. A Cultural Resources Survey of the Whitlow Ranch Dam and Reservoir Area, Eastern Pinal County, Arizona,

    DTIC Science & Technology

    1986-01-01

    RESERVOIR AREA, EASTERN PINAL COUNTY , ARIZONA By L Lee Fratt ELECYI. . andSE1 N David A. Phillips, Jr. SP1818 With Contributions By Maryanne Frederickson...Survel Whitlow Ranch Dam and Reservoir Area, , Eastern Pinal County , Arizona * PERFORMING ORG. REPORT NUMBER 7. AUTHOR() NA Lee Fratt and David A...attempts at evaluation. V ’p*!~ A CULTURAL RESOURCES SURVEY OF THE WHITLOW RANCH DAN AND RESERVOIR AREA, EASTERN PINAL COUNTY , ARIZONA By Lee Fratt and David

  11. A new rhenanite (beta-NaCaPO(4)) and hydroxyapatite biphasic biomaterial for skeletal repair.

    PubMed

    Jalota, Sahil; Bhaduri, Sarit B; Tas, A Cuneyt

    2007-02-01

    Biphasic beta-rhenanite (beta-NaCaPO(4))-hydroxyapatite (Ca(10)(PO(4))(6)(OH)(2)) biomaterials were prepared by using a one-pot, solution-based synthesis procedure at the physiological pH of 7.4, followed by low-temperature (300-600 degrees C) calcination in air for 6 h. Calcination was for the sole purpose of crystallization. An aqueous solution of Ca(NO(3))(2). 4H(2)O was rapidly added to a solution of Na(2)HPO(4) and NaHCO(3), followed by immediate removal of gel-like, poorly-crystallized precursor precipitates from the mother liquors of pH 7.4. Freeze-dried precursors were found to be nanosize with an average particle size of 45 nm and a surface area of 128 m(2)/g. Upon calcination in air, precursor powders crystallized into biphasic (60% HA-40% rhenanite) biomaterials, while retaining their submicron particle sizes and high surface areas. beta-rhenanite is a high solubility sodium calcium phosphate phase. Samples were characterized by XRD, FTIR, SEM, TEM, ICP-AES, TG, DTA, DSC, and surface area measurements.

  12. Na/K-ATPase Mimetic pNaKtide Peptide Inhibits the Growth of Human Cancer Cells*

    PubMed Central

    Li, Zhichuan; Zhang, Zhongbing; Xie, Joe X.; Li, Xin; Tian, Jiang; Cai, Ting; Cui, Hongjuan; Ding, Hanfei; Shapiro, Joseph I.; Xie, Zijian

    2011-01-01

    Cells contain a large pool of nonpumping Na/K-ATPase that participates in signal transduction. Here, we show that the expression of α1 Na/K-ATPase is significantly reduced in human prostate carcinoma as well as in several human cancer cell lines. This down-regulation impairs the ability of Na/K-ATPase to regulate Src-related signaling processes. A supplement of pNaKtide, a peptide derived from α1 Na/K-ATPase, reduces the activities of Src and Src effectors. Consequently, these treatments stimulate apoptosis and inhibit growth in cultures of human cancer cells. Moreover, administration of pNaKtide inhibits angiogenesis and growth of tumor xenograft. Thus, the new findings demonstrate the in vivo effectiveness of pNaKtide and suggest that the defect in Na/K-ATPase-mediated signal transduction may be targeted for developing new anticancer therapeutics. PMID:21784855

  13. Reflectivity of NaK Droplets

    NASA Astrophysics Data System (ADS)

    Wiedemann, C.; Oswald, M.; Stabroth, S.; Klinkrad, H.; Vörsmann, P.

    An important contribution to the space debris population near 900 km orbital altitude are the NaK droplets. Sixteen nuclear powered satellites of the type RORSAT launched between 1980 and 1988 activated a reactor core ejection system close to this altitude. The core ejection causes an opening of the primary coolant circuit. The liquid coolant has been released into space during these core ejections, forming droplets up to a diameter of 5.5 cm. These droplets consist of an alloy of two alkali metals, sodium and potassium (NaK). In this paper the monochromatic and the total reflectivity of NaK is calculated using theoretical models. The reflectivity depends on the alloy composition and temperature of a droplet. The alloy composition may change due to evaporation, resulting in an enrichment of sodium especially at the droplet surface. According to the literature, there is only a limited number of available measurement data concerning the optical properties of NaK alloys. Furthermore the published data for pure sodium and potassium are controversial. Thus it is necessary to investigate the optical properties of alkali metals and their alloys. Mainly two types of optical absorption, the intraband and the interband absorption, are considered. The intraband absorption is calculated using the Drude-model which uses electrical properties to derive the optical constants of pure metals or alloys. Drude assumes that the valence electrons can be treated as free electrons. The electrons behave like an ideal gas of uncharged particles. The theory of free electrons is a very simple model for the description of the valence electrons in metals. This assumption is sufficient for alkali metals, because they show a nearly free electron behavior. For the interband absorption the classical Butcher-model is used. Furthermore an absorption anomaly which has been observed in some alkali metals is discussed. Especially for potassium, some measurements revealed an unexpected absorption in the

  14. Na-Ion Battery Anodes: Materials and Electrochemistry.

    PubMed

    Luo, Wei; Shen, Fei; Bommier, Clement; Zhu, Hongli; Ji, Xiulei; Hu, Liangbing

    2016-02-16

    The intermittent nature of renewable energy sources, such as solar and wind, calls for sustainable electrical energy storage (EES) technologies for stationary applications. Li will be simply too rare for Li-ion batteries (LIBs) to be used for large-scale storage purposes. In contrast, Na-ion batteries (NIBs) are highly promising to meet the demand of grid-level storage because Na is truly earth abundant and ubiquitous around the globe. Furthermore, NIBs share a similar rocking-chair operation mechanism with LIBs, which potentially provides high reversibility and long cycling life. It would be most efficient to transfer knowledge learned on LIBs during the last three decades to the development of NIBs. Following this logic, rapid progress has been made in NIB cathode materials, where layered metal oxides and polyanionic compounds exhibit encouraging results. On the anode side, pure graphite as the standard anode for LIBs can only form NaC64 in NIBs if solvent co-intercalation does not occur due to the unfavorable thermodynamics. In fact, it was the utilization of a carbon anode in LIBs that enabled the commercial successes. Anodes of metal-ion batteries determine key characteristics, such as safety and cycling life; thus, it is indispensable to identify suitable anode materials for NIBs. In this Account, we review recent development on anode materials for NIBs. Due to the limited space, we will mainly discuss carbon-based and alloy-based anodes and highlight progress made in our groups in this field. We first present what is known about the failure mechanism of graphite anode in NIBs. We then go on to discuss studies on hard carbon anodes, alloy-type anodes, and organic anodes. Especially, the multiple functions of natural cellulose that is used as a low-cost carbon precursor for mass production and as a soft substrate for tin anodes are highlighted. The strategies of minimizing the surface area of carbon anodes for improving the first-cycle Coulombic efficiency are

  15. Heterogeneous Reaction of ClONO2(g) + NaCl(s) to Cl2(g) + NaNO3(s)

    NASA Technical Reports Server (NTRS)

    Timonen, Raimo S.; Chu, Liang T.; Leu, Ming-Taun; Keyser, Leon F.

    1994-01-01

    The heterogeneous reaction of ClON02 + NaCl yields Cl2 + NaNO3 (eq 1) was investigated over a temperature range 220-300 K in a flow-tube reactor interfaced with a differentially pumped quadrupole mass spectrometer. Partial pressures of ClON02 in the range 10(exp -8) - 10(exp -5) Torr were used. Granule sizes and surface roughness of the NaCl substrates were determined by using a scanning electron microscope, and in separate experiments, surface areas of the substrates were measured by using BET analysis of gas-adsorption isotherms. For dry NaCl substrates, both the decay rates of ClON02 and the growth rates Of C12 were used to obtain reaction probabilities, gamma(sub l) = (4.6 +/- 3.0) x 10(exp -3) at 296 K and (6.7 +/- 3.2) x 10(exp -1) at 225 K, after considering the internal surface area, The error bars represent 1 standard deviation. The Cl2 yield based on the ClONO2 reacted was measured to be 1.0 +/- 0.2. In order to mimic the conditions encountered in the lower stratosphere, the effect of water vapor pressures between 5 x 10(exp -5) and 3 x 10(exp -4) Torr on reaction 1 was also studied. With added H20, reaction probabilities, gamma = (4.1 +/- 2.1) x 10(exp -3) at 296 K and (4.7 +/- 2.9) x 10(exp -3) at 225 K, were obtained. A trace of HOCl, the reaction product from the ClON02 + H20 yield HOCl + HN03 reaction, was observed in addition to the C12 product from reaction 1. The implications of this result for the enhancement of hydrogen chloride in the stratosphere after the El Chichon volcanic eruption and for the marine troposphere are discussed.

  16. Some aspects of salinity responses in peppermint (Mentha × piperita L.) to NaCl treatment.

    PubMed

    Li, Zhe; Yang, Hetong; Wu, Xiaoqing; Guo, Kai; Li, Jishun

    2015-05-01

    Salinity is a major stress that adversely affects plant growth and crop production. Understanding the cellular responses and molecular mechanisms by which plants perceive and adopt salinity stress is of fundamental importance. In this work, some of the cellular signaling events including cell death, reactive oxygen species (ROS) generation, and the behaviors of organelles were analyzed in a salt-tolerant species (Keyuan-1) of peppermint (Mentha × piperita L.) under NaCl treatment. Our results showed that 200 mM NaCl treatment elicited a distinct progress of cell death with chromatin condensation and caspase-3-like activation and a dramatic burst of ROS which was required for the execution of cell death. The major ROS accumulation occurred in the mitochondria and chloroplasts, which were the sources of ROS production under NaCl stress. Moreover, mitochondrial activity and photosynthetic capacity also exhibited the obvious decrease in the ROS-dependent manner under 200 mM NaCl stress. Furthermore, the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR), and dehydroascorbate reductase (DHAR) as well as the contents of ascorbate and glutathione changed in the concentration-dependent manner under NaCl stress. Altogether, our data showed the execution of programmed cell death (PCD), the ROS dynamics, and the behaviors of organelles especially mitochondria and chloroplasts in the cellular responses of peppermint to NaCl stress which can be used for the tolerance screening, and contributed to the understanding of the cellular responses and molecular mechanisms of peppermint to salinity stress, providing the theoretic basis for the further development and utilization of peppermint in saline areas.

  17. Thermo-Raman spectroscopic studies on polymorphism in Na2SO4

    NASA Astrophysics Data System (ADS)

    Murugan, Ramaswamy; Ghule, Anil; Chang, Hua

    2000-02-01

    The phase transformations involved in Na2 SO4 (Na2 SO4 icons/Journals/Common/cdot" ALT="cdot" ALIGN="TOP"/> 10H2 O as starting material) and predried Na2 SO4 in a dynamic thermal process of heating from 30 to 500 °C and then cooling down to 30 °C, with a heating/cooling rate of 2 °C min-1 in two consecutive thermal cycles, were monitored at 1 °C intervals by thermo-Raman spectroscopy (TRS). The transformations were characterized on the basis of the disappearance of the bands, appearance of new bands, splitting in the internal modes, change in the spectral profile, intensity (area) changes in the internal modes, full width at half maximum (FWHM) of the totally symmetric stretching mode and even the variations observed in the background during the thermal process. This thermo-Raman investigation provided some evidence for the existence of an intermediate phase between phase V and phase I and also for the changes observed in the phase I structure at higher temperatures, in addition to the dynamic transformations between the well known phase V, phase I, phase II and phase III. The intensity study on the icons/Journals/Common/nu" ALT="nu" ALIGN="TOP"/> 3 mode of SO2- 4 clearly demonstrated the thermal hysteresis involved among the phases during the heating and cooling process. The differences observed in the polymorphisms of Na2 SO4 (Na2 SO4 icons/Journals/Common/cdot" ALT="cdot" ALIGN="TOP"/> 10H2 O as starting material) and predried Na2 SO4 were also discussed.

  18. Route, mechanism, and implications of proton import during Na+/K+ exchange by native Na+/K+-ATPase pumps.

    PubMed

    Vedovato, Natascia; Gadsby, David C

    2014-04-01

    A single Na(+)/K(+)-ATPase pumps three Na(+) outwards and two K(+) inwards by alternately exposing ion-binding sites to opposite sides of the membrane in a conformational sequence coupled to pump autophosphorylation from ATP and auto-dephosphorylation. The larger flow of Na(+) than K(+) generates outward current across the cell membrane. Less well understood is the ability of Na(+)/K(+) pumps to generate an inward current of protons. Originally noted in pumps deprived of external K(+) and Na(+) ions, as inward current at negative membrane potentials that becomes amplified when external pH is lowered, this proton current is generally viewed as an artifact of those unnatural conditions. We demonstrate here that this inward current also flows at physiological K(+) and Na(+) concentrations. We show that protons exploit ready reversibility of conformational changes associated with extracellular Na(+) release from phosphorylated Na(+)/K(+) pumps. Reversal of a subset of these transitions allows an extracellular proton to bind an acidic side chain and to be subsequently released to the cytoplasm. This back-step of phosphorylated Na(+)/K(+) pumps that enables proton import is not required for completion of the 3 Na(+)/2 K(+) transport cycle. However, the back-step occurs readily during Na(+)/K(+) transport when external K(+) ion binding and occlusion are delayed, and it occurs more frequently when lowered extracellular pH raises the probability of protonation of the externally accessible carboxylate side chain. The proton route passes through the Na(+)-selective binding site III and is distinct from the principal pathway traversed by the majority of transported Na(+) and K(+) ions that passes through binding site II. The inferred occurrence of Na(+)/K(+) exchange and H(+) import during the same conformational cycle of a single molecule identifies the Na(+)/K(+) pump as a hybrid transporter. Whether Na(+)/K(+) pump-mediated proton inflow may have any physiological or

  19. DOR activation inhibits anoxic/ischemic Na+ influx through Na+ channels via PKC mechanisms in the cortex

    PubMed Central

    Chao, Dongman; He, Xiaozhou; Yang, Yilin; Bazzy-Asaad, Alia; Lazarus, Lawrence H.; Balboni, Gianfranco; Kim, Dong H.; Xia, Ying

    2012-01-01

    Activation of delta-opioid receptors (DOR) is neuroprotective against hypoxic/ischemic injury in the cortex, which is at least partially related to its action against hypoxic/ischemic disruption of ionic homeostasis that triggers neuronal injury. Na+ influx through TTX-sensitive voltage-gated Na+ channels may be a main mechanism for hypoxia-induced disruption of K+ homeostasis, with DOR activation attenuating the disruption of ionic homeostasis by targeting voltage-gated Na+ channels. In the present study we examined the role of DOR in the regulation of Na+ influx in anoxia and simulated ischemia (oxygen-glucose deprivation) as well as the effect of DOR activation on the Na+ influx induced by a Na+ channel opener without anoxic/ischemic stress and explored a potential PKC mechanism underlying the DOR action. We directly measured extracellular Na+ activity in mouse cortical slices with Na+ selective electrodes and found that (1) anoxia-induced Na+ influx occurred mainly through TTX-sensitive Na+ channels; (2) DOR activation inhibited the anoxia/ischemia-induced Na+ influx; (3) veratridine, a Na+ channel opener, enhanced the anoxia-induced Na+ influx; this could be attenuated by DOR activation; (4) DOR activation did not reduce the anoxia-induced Na+ influx in the presence of chelerythrine, a broad-spectrum PKC blocker; and (5) DOR effects were blocked by PKCβII peptide inhibitor, and PKCθ pseudosubstrate inhibitor, respectively. We conclude that DOR activation inhibits anoxia-induced Na+ influx through Na+ channels via PKC (especially PKCβII and PKCθ isoforms) dependent mechanisms in the cortex. PMID:22609332

  20. GiNA, an Efficient and High-Throughput Software for Horticultural Phenotyping

    PubMed Central

    Diaz-Garcia, Luis; Covarrubias-Pazaran, Giovanny; Schlautman, Brandon; Zalapa, Juan

    2016-01-01

    Traditional methods for trait phenotyping have been a bottleneck for research in many crop species due to their intensive labor, high cost, complex implementation, lack of reproducibility and propensity to subjective bias. Recently, multiple high-throughput phenotyping platforms have been developed, but most of them are expensive, species-dependent, complex to use, and available only for major crops. To overcome such limitations, we present the open-source software GiNA, which is a simple and free tool for measuring horticultural traits such as shape- and color-related parameters of fruits, vegetables, and seeds. GiNA is multiplatform software available in both R and MATLAB® programming languages and uses conventional images from digital cameras with minimal requirements. It can process up to 11 different horticultural morphological traits such as length, width, two-dimensional area, volume, projected skin, surface area, RGB color, among other parameters. Different validation tests produced highly consistent results under different lighting conditions and camera setups making GiNA a very reliable platform for high-throughput phenotyping. In addition, five-fold cross validation between manually generated and GiNA measurements for length and width in cranberry fruits were 0.97 and 0.92. In addition, the same strategy yielded prediction accuracies above 0.83 for color estimates produced from images of cranberries analyzed with GiNA compared to total anthocyanin content (TAcy) of the same fruits measured with the standard methodology of the industry. Our platform provides a scalable, easy-to-use and affordable tool for massive acquisition of phenotypic data of fruits, seeds, and vegetables. PMID:27529547

  1. GiNA, an Efficient and High-Throughput Software for Horticultural Phenotyping.

    PubMed

    Diaz-Garcia, Luis; Covarrubias-Pazaran, Giovanny; Schlautman, Brandon; Zalapa, Juan

    2016-01-01

    Traditional methods for trait phenotyping have been a bottleneck for research in many crop species due to their intensive labor, high cost, complex implementation, lack of reproducibility and propensity to subjective bias. Recently, multiple high-throughput phenotyping platforms have been developed, but most of them are expensive, species-dependent, complex to use, and available only for major crops. To overcome such limitations, we present the open-source software GiNA, which is a simple and free tool for measuring horticultural traits such as shape- and color-related parameters of fruits, vegetables, and seeds. GiNA is multiplatform software available in both R and MATLAB® programming languages and uses conventional images from digital cameras with minimal requirements. It can process up to 11 different horticultural morphological traits such as length, width, two-dimensional area, volume, projected skin, surface area, RGB color, among other parameters. Different validation tests produced highly consistent results under different lighting conditions and camera setups making GiNA a very reliable platform for high-throughput phenotyping. In addition, five-fold cross validation between manually generated and GiNA measurements for length and width in cranberry fruits were 0.97 and 0.92. In addition, the same strategy yielded prediction accuracies above 0.83 for color estimates produced from images of cranberries analyzed with GiNA compared to total anthocyanin content (TAcy) of the same fruits measured with the standard methodology of the industry. Our platform provides a scalable, easy-to-use and affordable tool for massive acquisition of phenotypic data of fruits, seeds, and vegetables.

  2. A computational study of Na behavior on graphene

    NASA Astrophysics Data System (ADS)

    Malyi, Oleksandr I.; Sopiha, Kostiantyn; Kulish, Vadym V.; Tan, Teck L.; Manzhos, Sergei; Persson, Clas

    2015-04-01

    We present the first ab initio and molecular dynamics study of Na adsorption and diffusion on ideal graphene that considers Na-Na interaction and dispersion forces. From density functional theory (DFT) calculations using the generalized gradient approximation (GGA), the binding energy (vs. the vacuum reference state) of -0.75 eV is higher than the cohesive energy of Na metal (ENa metal cohesive energy (EcohDFT - D = - 1.21 eV) when dispersion correction is included (DFT-D), with Eb = -1.14 eV. Both DFT and DFT-D predict that the increase of Na concentration on graphene results in formation of Na complexes. This is evidenced by smaller Bader charge on Na atoms of Na dimer, 0.55e (0.48e for DFT) compared to 0.86e (for both DFT and DFT-D) for the single atom adsorption as well as by the formation of a Nasbnd Na bond identified by analysis of the electron density. These results suggest that ideal graphene is not a promising anode material for Na-ion batteries. Analysis of diffusion pathways for a Na dimer shows that the dimer remains stable during the diffusion, and computed migration barriers are significantly lower for the dimer than that for the single atom diffusion. This indicates that Na-Na interaction should be taken into account during the analysis of Na transport on graphene. Finally, we show that the typical defects (vacancy and divacancy) induce significant strengthening of the Nasbnd C interaction. In particular, the largest change to the interaction is computed for vacancy-defected graphene, where the found lowest binding energy (vs. the metal reference state) is about 1.15 eV (1.21 eV for DFT) lower than that for ideal graphene.

  3. pNaKtide inhibits Na/K-ATPase reactive oxygen species amplification and attenuates adipogenesis

    PubMed Central

    Sodhi, Komal; Maxwell, Kyle; Yan, Yanling; Liu, Jiang; Chaudhry, Muhammad A.; Getty, Morghan; Xie, Zijian; Abraham, Nader G.; Shapiro, Joseph I.

    2015-01-01

    Obesity has become a worldwide epidemic and is a major risk factor for metabolic syndrome. Oxidative stress is known to play a role in the generation and maintenance of an obesity phenotype in both isolated adipocytes and intact animals. Because we had identified that the Na/K-ATPase can amplify oxidant signaling, we speculated that a peptide designed to inhibit this pathway, pNaKtide, might ameliorate an obesity phenotype. To test this hypothesis, we first performed studies in isolated murine preadipocytes (3T3L1 cells) and found that pNaKtide attenuated oxidant stress and lipid accumulation in a dose-dependent manner. Complementary experiments in C57Bl6 mice fed a high-fat diet corroborated our in vitro observations. Administration of pNaKtide in these mice reduced body weight gain, restored systemic redox and inflammatory milieu, and, crucially, improved insulin sensitivity. Thus, we propose that inhibition of Na/K-ATPase amplification of oxidative stress may ultimately be a novel way to combat obesity, insulin resistance, and metabolic syndrome. PMID:26601314

  4. Zero-gravity growth of NaF-NaCl eutectics in the NASA Skylab program

    NASA Technical Reports Server (NTRS)

    Yue, A. S.; Allen, F. G.; Yu, J. G.

    1976-01-01

    Continuous and discontinuous NaF fibers, embedded in a NaCl matrix, were produced in space and on earth. The production of continuous fibers in a eutectic mixture is attributed to the absence of convection current in the liquid during solidification in space. Image transmission and optical transmittance measurements of transverse sections of the space-grown and earth-grown ingots were made with a light microscope and a spectrometer. It is shown that better optical properties were obtained from samples grown in space. This was attributed to a better alignment of NaF fibers along the ingot axis. A new concept is advanced to explain the phenomenon of transmittance versus far infrared wavelength of the directionally solidified NaCl-NaF eutectic in terms of the two-dimensional Bragg Scattering and the polarization effect of Rayleigh scattering. This concept can be applied to other eutectic systems as long as the index of refraction of the matrix over a range of wavelengths is known. Experimental data are in agreement with the theoretical prediction.

  5. Post-Closure Groundwater Monitoring Plan for the 1324-N Surface Impoundment and 1324-NA Percolation Pond

    SciTech Connect

    Hartman, Mary J.

    2004-04-02

    The 1324-N Surface Impoundment and the 1324-NA Percolation Pond, located in the 100-N Area of the Hanford Site, are regulated under the Resource Consevation and Recovery Act (RCRA). Surface and underground features of the facilities have been removed and laboratory analyses showed that soil met the closure performance standards. These sites have been backfilled and revegetated.

  6. Plant Defensins NaD1 and NaD2 Induce Different Stress Response Pathways in Fungi

    PubMed Central

    Dracatos, Peter M.; Payne, Jennifer; Di Pietro, Antonio; Anderson, Marilyn A.; Plummer, Kim M.

    2016-01-01

    Nicotiana alata defensins 1 and 2 (NaD1 and NaD2) are plant defensins from the ornamental tobacco that have antifungal activity against a variety of fungal pathogens. Some plant defensins interact with fungal cell wall O-glycosylated proteins. Therefore, we investigated if this was the case for NaD1 and NaD2, by assessing the sensitivity of the three Aspergillus nidulans (An) O-mannosyltransferase (pmt) knockout (KO) mutants (An∆pmtA, An∆pmtB, and An∆pmtC). An∆pmtA was resistant to both defensins, while An∆pmtC was resistant to NaD2 only, suggesting NaD1 and NaD2 are unlikely to have a general interaction with O-linked side chains. Further evidence of this difference in the antifungal mechanism was provided by the dissimilarity of the NaD1 and NaD2 sensitivities of the Fusarium oxysporum f. sp. lycopersici (Fol) signalling knockout mutants from the cell wall integrity (CWI) and high osmolarity glycerol (HOG) mitogen-activated protein kinase (MAPK) pathways. HOG pathway mutants were sensitive to both NaD1 and NaD2, while CWI pathway mutants only displayed sensitivity to NaD2. PMID:27598152

  7. Plant Defensins NaD1 and NaD2 Induce Different Stress Response Pathways in Fungi.

    PubMed

    Dracatos, Peter M; Payne, Jennifer; Di Pietro, Antonio; Anderson, Marilyn A; Plummer, Kim M

    2016-09-03

    Nicotiana alata defensins 1 and 2 (NaD1 and NaD2) are plant defensins from the ornamental tobacco that have antifungal activity against a variety of fungal pathogens. Some plant defensins interact with fungal cell wall O-glycosylated proteins. Therefore, we investigated if this was the case for NaD1 and NaD2, by assessing the sensitivity of the three Aspergillus nidulans (An) O-mannosyltransferase (pmt) knockout (KO) mutants (An∆pmtA, An∆pmtB, and An∆pmtC). An∆pmtA was resistant to both defensins, while An∆pmtC was resistant to NaD2 only, suggesting NaD1 and NaD2 are unlikely to have a general interaction with O-linked side chains. Further evidence of this difference in the antifungal mechanism was provided by the dissimilarity of the NaD1 and NaD2 sensitivities of the Fusarium oxysporum f. sp. lycopersici (Fol) signalling knockout mutants from the cell wall integrity (CWI) and high osmolarity glycerol (HOG) mitogen-activated protein kinase (MAPK) pathways. HOG pathway mutants were sensitive to both NaD1 and NaD2, while CWI pathway mutants only displayed sensitivity to NaD2.

  8. Na+ channel function, regulation, structure, trafficking and sequestration

    PubMed Central

    Chen-Izu, Ye; Shaw, Robin M; Pitt, Geoffrey S; Yarov-Yarovoy, Vladimir; Sack, Jon T; Abriel, Hugues; Aldrich, Richard W; Belardinelli, Luiz; Cannell, Mark B; Catterall, William A; Chazin, Walter J; Chiamvimonvat, Nipavan; Deschenes, Isabelle; Grandi, Eleonora; Hund, Thomas J; Izu, Leighton T; Maier, Lars S; Maltsev, Victor A; Marionneau, Celine; Mohler, Peter J; Rajamani, Sridharan; Rasmusson, Randall L; Sobie, Eric A; Clancy, Colleen E; Bers, Donald M

    2015-01-01

    This paper is the second of a series of three reviews published in this issue resulting from the University of California Davis Cardiovascular Symposium 2014: Systems approach to understanding cardiac excitation–contraction coupling and arrhythmias: Na+ channel and Na+ transport. The goal of the symposium was to bring together experts in the field to discuss points of consensus and controversy on the topic of sodium in the heart. The present review focuses on Na+ channel function and regulation, Na+ channel structure and function, and Na+ channel trafficking, sequestration and complexing. PMID:25772290

  9. Na+-K+ pump regulation and skeletal muscle contractility.

    PubMed

    Clausen, Torben

    2003-10-01

    In skeletal muscle, excitation may cause loss of K+, increased extracellular K+ ([K+]o), intracellular Na+ ([Na+]i), and depolarization. Since these events interfere with excitability, the processes of excitation can be self-limiting. During work, therefore, the impending loss of excitability has to be counterbalanced by prompt restoration of Na+-K+ gradients. Since this is the major function of the Na+-K+ pumps, it is crucial that their activity and capacity are adequate. This is achieved in two ways: 1) by acute activation of the Na+-K+ pumps and 2) by long-term regulation of Na+-K+ pump content or capacity. 1) Depending on frequency of stimulation, excitation may activate up to all of the Na+-K+ pumps available within 10 s, causing up to 22-fold increase in Na+ efflux. Activation of the Na+-K+ pumps by hormones is slower and less pronounced. When muscles are inhibited by high [K+]o or low [Na+]o, acute hormone- or excitation-induced activation of the Na+-K+ pumps can restore excitability and contractile force in 10-20 min. Conversely, inhibition of the Na+-K+ pumps by ouabain leads to progressive loss of contractility and endurance. 2) Na+-K+ pump content is upregulated by training, thyroid hormones, insulin, glucocorticoids, and K+ overload. Downregulation is seen during immobilization, K+ deficiency, hypoxia, heart failure, hypothyroidism, starvation, diabetes, alcoholism, myotonic dystrophy, and McArdle disease. Reduced Na+-K+ pump content leads to loss of contractility and endurance, possibly contributing to the fatigue associated with several of these conditions. Increasing excitation-induced Na+ influx by augmenting the open-time or the content of Na+ channels reduces contractile endurance. Excitability and contractility depend on the ratio between passive Na+-K+ leaks and Na+-K+ pump activity, the passive leaks often playing a dominant role. The Na+-K+ pump is a central target for regulation of Na+-K+ distribution and excitability, essential for second

  10. Metropolitan area of Chicago

    NASA Image and Video Library

    1973-09-18

    SL3-88-222 (18 Sept. 1973) --- The metropolitan area of Chicago is encompassed in this Skylab 3 Earth Resources Experiments Package (EREP) S190-B photograph taken on Sept. 18, 1973 from the Skylab space station cluster in Earth orbit. The surrounding major cities of Aurora and Joliet, Illinois; Hammond, Gary and East Chicago, Indiana, are easily delineated. The photograph reveals the following: (1) Cultural differentiation of commercial, industrial and residential areas for use in population and social studies in micro-macro community planning and in cultural pattern studies in the improvement of urban areas. (Aurora is one of 27 census cities of interest to Robert Alexander, a principal investigator. Alexander is with the U.S. Geological Survey). (2) The transportation network with major corridors and their interchanges, primary and feeder streets for use in network analysis and in the development of models for population movement and land use projection. (3) The agricultural lands for land use identification on crop inventory analysis; airports for use in delineation of service and infringement of major man-made features that affect ecosystem balance (support to environmental impact studies). (4) Air and water plumes for use in case studies, natural and man-made differentiation of pollution sources, in support of model development and in ecosystem research studies on the effects of pollution. (5) Recreational centers for use in relating recreational centers to population centers, establishing possible demands and in development of possible future recreational centers to support the demand. All EREP photography is available to the public through the Department of Interior?s Earth Resources Observations Systems Data Center, Sioux Falls, South Dakota, 57198. Photo credit: NASA

  11. Acidosis Differentially Modulates Inactivation in NaV1.2, NaV1.4, and NaV1.5 Channels

    PubMed Central

    Vilin, Yury Y.; Peters, Colin H.; Ruben, Peter C.

    2012-01-01

    NaV channels play a crucial role in neuronal and muscle excitability. Using whole-cell recordings we studied effects of low extracellular pH on the biophysical properties of NaV1.2, NaV1.4, and NaV1.5, expressed in cultured mammalian cells. Low pH produced different effects on different channel subtypes. Whereas NaV1.4 exhibited very low sensitivity to acidosis, primarily limited to partial block of macroscopic currents, the effects of low pH on gating in NaV1.2 and NaV1.5 were profound. In NaV1.2 low pH reduced apparent valence of steady-state fast inactivation, shifted the τ(V) to depolarizing potentials and decreased channels availability during onset to slow and use-dependent inactivation (UDI). In contrast, low pH delayed open-state inactivation in NaV1.5, right-shifted the voltage-dependence of window current, and increased channel availability during onset to slow and UDI. These results suggest that protons affect channel availability in an isoform-specific manner. A computer model incorporating these results demonstrates their effects on membrane excitability. PMID:22701426

  12. Large area bulk superconductors

    DOEpatents

    Miller, Dean J.; Field, Michael B.

    2002-01-01

    A bulk superconductor having a thickness of not less than about 100 microns is carried by a polycrystalline textured substrate having misorientation angles at the surface thereof not greater than about 15.degree.; the bulk superconductor may have a thickness of not less than about 100 microns and a surface area of not less than about 50 cm.sup.2. The textured substrate may have a thickness not less than about 10 microns and misorientation angles at the surface thereof not greater than about 15.degree.. Also disclosed is a process of manufacturing the bulk superconductor and the polycrystalline biaxially textured substrate material.

  13. Hydrogeochemical characterization and Natural Background Levels in urbanized areas: Milan Metropolitan area (Northern Italy)

    NASA Astrophysics Data System (ADS)

    De Caro, Mattia; Crosta, Giovanni B.; Frattini, Paolo

    2017-04-01

    Although aquifers in densely populated and industrialized areas are extremely valuable and sensitive to contamination, an estimate of the groundwater quality status relative to baseline conditions is lacking for many of them. This paper provides a hydrogeochemical characterization of the groundwater in the Milan metropolitan area, one of the most densely populated areas in Europe. First, a conceptual model of the study area based on the analysis of the spatial distribution of natural chemical species and indicator contaminants is presented. The hydrochemical facies of the study area depend on the lithology of catchments drained by the main contributing rivers and on the aquifer settings. The anthropogenic influence on the groundwater quality of superficial aquifers is studied by means of probability plots, concentration versus depth plots and spatial-temporal plots for nitrate, sulfate and chloride. These allow differentiation of contaminated superficial aquifers from deep confined aquifers with baseline water quality. Natural Background Levels (NBL) of selected species (Cl, Na, NH4, SO4, NO3, As, Fe, Mn and Zn) are estimated by means of the pre-selection (PS) and the component separation (CS) statistical approaches. The NBLs depend on hydrogeological settings of the study area; sodium, chloride, sulfate and zinc NBL values never exceed the environmental water quality standards. NBL values of ammonium, iron, arsenic and manganese exceed the environmental water quality standards in the anaerobic portion of the aquifers. On the basis of observations, a set of criteria and precautions are suggested for adoption with both PS and CS methods in the aquifer characterization of highly urbanized areas.

  14. Shank2 redistributes with NaPilla during regulated endocytosis

    PubMed Central

    Dobrinskikh, Evgenia; Giral, Hector; Caldas, Yupanqui A.; Levi, Moshe

    2010-01-01

    Serum phosphate levels are acutely impacted by the abundance of sodium-phosphate cotransporter IIa (NaPiIIa) in the apical membrane of renal proximal tubule cells. PSD-95/Disks Large/Zonula Occludens (PDZ) domain-containing proteins bind NaPiIIa and likely contribute to the delivery, retention, recovery, and trafficking of NaPiIIa. Shank2 is a distinctive PDZ domain protein that binds NaPiIIa. Its role in regulating NaPiIIa activity, distribution, and abundance is unknown. In the present in vivo study, rats were maintained on a low-phosphate diet, and then plasma phosphate levels were acutely elevated by high-phosphate feeding to induce the recovery, endocytosis, and degradation of NaPiIIa. Western blot analysis of renal cortical tissue from rats given high-phosphate feed showed NaPiIIa and Shank2 underwent degradation. Quantitative immunofluorescence analyses, including microvillar versus intracellular intensity ratios and intensity correlation quotients, showed that Shank2 redistributed with NaPiIIa during the time course of NaPiIIa endocytosis. Furthermore, NaPiIIa and Shank2 trafficked through distinct endosomal compartments (clathrin, early endosomes, lysosomes) with the same temporal pattern. These in vivo findings indicate that Shank2 is positioned to coordinate the regulated endocytic retrieval and downregulation of NaPiIIa in rat renal proximal tubule cells. PMID:20810910

  15. Jahn–Teller Assisted Na Diffusion for High Performance Na Ion Batteries

    SciTech Connect

    Li, Xin; Wang, Yan; Wu, Di; Liu, Lei; Bo, Shou-Hang; Ceder, Gerbrand

    2016-08-30

    Na energy storage technology is strategically attractive for large scale applications such as grid energy storage. Here, we show in this paper that there is a clear relation between the Jahn$-$Teller activity of a transition metal ion at the end of charge and the mobility of Na in a cathode material. This is particularly important as mobility at the end of charge limits the capacity of current materials. Consequently, by using this classical piece of physics in the battery world, it is possible to create higher capacity Na-cathode materials. Even more exciting is that the ideal element to impart this effect on cathodes is Fe, which is the least expensive of the transition metal oxides and can therefore enable low cost cathode materials.

  16. Uncratered Area on Mercury

    NASA Technical Reports Server (NTRS)

    1974-01-01

    A dark, smooth, relatively uncratered area on Mercury was photographed (FDS 226) two hours after Mariner 10 flew by the planet on March 29 from a range of 86,000 kilometers (54,000 miles). Above and to the left of center is a surface similar to the mane material of Earth's moon. It embays and covers rougher, older, heavily cratered topography like that, which can be seen in both upper corners of this picture. The history of heavy cratering seems to be followed by volcanic filling, similar to the process on the Moon. The prominent, sharp crater with a central peak (center) is 30 kilometers (19 miles) across. It is located on the upper left edge of a very bright surface area. The bright crater, to its right is 10 kilometers (6 miles) in diameter. The sun is from the right.

    The Mariner 10 mission, managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, explored Venus in February 1974 on the way to three encounters with Mercury-in March and September 1974 and in March 1975. The spacecraft took more than 7,000 photos of Mercury, Venus, the Earth and the Moon.

    Image Credit: NASA/JPL/Northwestern University

  17. Specific oxidation pattern of soluble starch with TEMPO-NaBr-NaClO system.

    PubMed

    Hao, Jie; Lu, Jiaojiao; Xu, Naiyu; Linhardt, Robert J; Zhang, Zhenqing

    2016-08-01

    Oxidized starch, one of the most important starch derivatives, has many different properties and applications. Currently, there are two ways to produce oxidized starch, through specific and nonspecific oxidation. Specific oxidation using the stable nitroxyl radical, 2,2,6,6-tetramethyl preparidinloxy (TEMPO), with NaBr and NaClO can produce oxidized starches with different properties under good quality control. In the current study, we examine the products of specifically oxidized starch. As the amount of oxidant and the temperature, two critical factors impacting the oxidation of starch were thoroughly investigated. Analysis of the molecular weight (MW), degree of oxidization (DO) and the detailed structures of corresponding products was accomplished using gel permeation chromatography with multi-angle laser light scattering (GPC-MALLS), infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and quadrapole time-of-flight mass spectrometry (Q/TOF-MS). According to the analytical results, the oxidation patterns of starch treated with specific oxidant TEMPO-NaBr-NaClO were established. When high amounts of oxidant was applied, more glucose residues within starch were oxidized to glucuronic acids (higher DO) and substantial degradation to starch oligosaccharides was observed. By selecting a reaction temperature of 25°C a high DO could be obtained for a given amount of oxidant. The reducing end sugar residue within oxidized starch was itself oxidized and ring opened in all TEMPO-NaBr-NaClO reactions. Furthermore, extra oxidant generated additional novel structures in the reducing end residues of some products, particularly in low temperature reactions.

  18. 7 CFR 966.4 - Production area and regulated area.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Production area and regulated area. 966.4 Section 966... SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Definitions § 966.4 Production area and regulated area....

  19. 7 CFR 966.4 - Production area and regulated area.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Production area and regulated area. 966.4 Section 966... SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Definitions § 966.4 Production area and regulated area....

  20. 7 CFR 966.4 - Production area and regulated area.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Production area and regulated area. 966.4 Section 966... SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Definitions § 966.4 Production area and regulated area....

  1. 7 CFR 966.4 - Production area and regulated area.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Production area and regulated area. 966.4 Section 966... SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Definitions § 966.4 Production area and regulated area....

  2. Genotypic difference in salinity tolerance in quinoa is determined by differential control of xylem Na(+) loading and stomatal density.

    PubMed

    Shabala, Sergey; Hariadi, Yuda; Jacobsen, Sven-Erik

    2013-07-01

    Quinoa is regarded as a highly salt tolerant halophyte crop, of great potential for cultivation on saline areas around the world. Fourteen quinoa genotypes of different geographical origin, differing in salinity tolerance, were grown under greenhouse conditions. Salinity treatment started on 10 day old seedlings. Six weeks after the treatment commenced, leaf sap Na and K content and osmolality, stomatal density, chlorophyll fluorescence characteristics, and xylem sap Na and K composition were measured. Responses to salinity differed greatly among the varieties. All cultivars had substantially increased K(+) concentrations in the leaf sap, but the most tolerant cultivars had lower xylem Na(+) content at the time of sampling. Most tolerant cultivars had lowest leaf sap osmolality. All varieties reduced stomata density when grown under saline conditions. All varieties clustered into two groups (includers and excluders) depending on their strategy of handling Na(+) under saline conditions. Under control (non-saline) conditions, a strong positive correlation was observed between salinity tolerance and plants ability to accumulate Na(+) in the shoot. Increased leaf sap K(+), controlled Na(+) loading to the xylem, and reduced stomata density are important physiological traits contributing to genotypic differences in salinity tolerance in quinoa, a halophyte species from Chenopodium family.

  3. The Formation of Sodium Stannate from Mineral Cassiterite by the Alkaline Decomposition Process with Sodium Carbonate (Na2CO3)

    NASA Astrophysics Data System (ADS)

    Andriyah, L.; Lalasari, L. H.; Manaf, A.

    2017-02-01

    Extraction of cassiterite using alkaline decomposition of sodium carbonate (Na2CO3) has been studied. Cassiterite (SnO2) is a mineral ore that contains tin (Sn) about 57.82 wt% and impurities like quartz, ilmenite, monazite, rutile and zircon. The initial step for the process was to remove the impurities in cassiterite through washing and separation by a high magnetic separator (HTS). The aim of this research is to increase the added value of cassiterite from local area Indonesia that using alkaline decomposition to form sodium stannate (Na2SnO3). The result shows that cassiterite from Indonesia can form sodium stannate (Na2SnO3) which soluble with water in the leaching process. The longer the time for decomposition, the more phases of sodium stannate that will be formed. Optimum result reached when the decomposition process was done in 850 °C for 4 hours with a mole ratio Na2CO3 to cassiterite 3:2. High Score Plus (HSP) was used in this research to analyze the mass of sodium stannate (Na2SnO3). HSP analysis showed that mass of sodium stannate (Na2SnO3) is 70.3 wt%.

  4. Design and implementation of the NaI(Tl)/CsI(Na) detectors output signal generator

    NASA Astrophysics Data System (ADS)

    Zhou, Xu; Liu, Cong-Zhan; Zhao, Jian-Ling; Zhang, Fei; Zhang, Yi-Fei; Li, Zheng-Wei; Zhang, Shuo; Li, Xu-Fang; Lu, Xue-Feng; Xu, Zhen-Ling; Lu, Fang-Jun

    2014-02-01

    We designed and implemented a signal generator that can simulate the output of the NaI(Tl)/CsI(Na) detectors' pre-amplifier onboard the Hard X-ray Modulation Telescope (HXMT). Using the development of the FPGA (Field Programmable Gate Array) with VHDL language and adding a random constituent, we have finally produced the double exponential random pulse signal generator. The statistical distribution of the signal amplitude is programmable. The occurrence time intervals of the adjacent signals contain negative exponential distribution statistically.

  5. Neutron spectroscopy of water dynamics in NaX and NaA zeolites

    NASA Astrophysics Data System (ADS)

    Kamitakahara, William A.; Wada, Noboru

    2008-04-01

    We have investigated the dynamics of water molecules in zeolites NaA and NaX by high-resolution quasielastic neutron scattering methods. Between 260 and 310 K, the local translational diffusive motion of water in the zeolites is one to two orders of magnitude slower than in bulk water. The Q dependence of the scattering shows effects of confinement and the presence of both relatively mobile and immobile molecules. The speed of the diffusive motion depends strongly on hydration level. Comparison with other hydrated siliceous materials indicates that the host charge per water molecule is a major factor in determining the time scale of diffusion.

  6. Wake-promoting effects of ONO-4127Na, a prostaglandin DP1 receptor antagonist, in hypocretin/orexin deficient narcoleptic mice.

    PubMed

    Sagawa, Yohei; Sato, Masatoshi; Sakai, Noriaki; Chikahisa, Sachiko; Chiba, Shintaro; Maruyama, Takashi; Yamamoto, Junki; Nishino, Seiji

    2016-11-01

    Prostaglandin (PG)D2 is an endogenous sleep substance, and a series of animal studies reported that PGD2 or PGD2 receptor (DP1) agonists promote sleep, while DP1 antagonists promote wakefulness. This suggests the possibility of use of PG DP1 antagonists as wake-promoting compounds. We therefore evaluated the wake-promoting effects of ONO-4127Na, a DP1 antagonist, in a mouse model of narcolepsy (i.e., orexin/ataxin-3 transgenic mice) and compared those to effects of modafinil. ONO-4127Na perfused in the basal forebrain (BF) area potently promoted wakefulness in both wild type and narcoleptic mice, and the wake-promoting effects of ONO-4127Na at 2.93 × 10(-4) M roughly corresponded to those of modafinil at 100 mg/kg (p.o.). The wake promoting effects of ONO-4127Na was observed both during light and dark periods, and much larger effects were seen during the light period when mice slept most of the time. ONO-4127Na, when perfused in the hypothalamic area, had no effects on sleep. We further demonstrated that wake-promoting effects of ONO-4127Na were abolished in DP1 KO mice, confirming that the wake-promoting effect of ONO-4127Na is mediated by blockade of the PG DP1 receptors located in the BF area. ONO-4127Na reduced DREM, an EEG/EMG assessment of behavioral cataplexy in narcoleptic mice, suggesting that ONO-4127Na is likely to have anticataplectic effects. DP1 antagonists may be a new class of compounds for the treatment of narcolepsy-cataplexy, and further studies are warranted.

  7. Direct Reactions with MoNA-LISA

    NASA Astrophysics Data System (ADS)

    Kuchera, Anthony

    2016-03-01

    Nuclear reactions can be used to probe the structure of nuclei. Direct reactions, which take place on short time scales, are well-suited for experiments with beams of short-lived nuclei. One such reaction is nucleon knockout where a proton or neutron is removed from the incoming beam from the interaction with a target. Single nucleon knockout reactions have been used to study the single-particle nature of nuclear wave functions. A recent experiment at the National Superconducting Cyclotron Laboratory was performed to measure cross sections from single nucleon knockout reactions for several p-shell nuclei. Detection of the residual nucleus in coincidence with any gamma rays emitted from the target allowed cross sections to ground and excited states to be measured. Together with input from reaction theory, ab initio structure theories can be tested. Simultaneously the accuracy of knockout reaction models can be validated by detecting the knocked out neutron with the Modular Neutron Array and Large multi-Institutional Scintillator Array (MoNA-LISA). Preliminary results from this experiment will be shown. Knockout reactions can also be used to populate nuclei which are neutron unbound, thus emit neutrons nearly instantaneously. The structure of these nuclei, therefore, cannot be probed with gamma ray spectroscopy. However, with large neutron detectors like MoNA-LISA the properties of these short-lived nuclei are able to be measured. Recent results using MoNA-LISA to study the structure of neutron-rich nuclei will be presented. The author would like to acknowledge support from the NNSA and NSF.

  8. Revisiting the hydration structure of aqueous Na+

    DOE PAGES

    Galib, M.; Baer, M. D.; Skinner, L. B.; ...

    2017-02-27

    In this paper, a combination of theory, X-ray diffraction (XRD) and extended x-ray absorption fine structure (EXAFS) are used to probe the hydration structure of aqueous Na+. The high spatial resolution of the XRD measurements corresponds to Qmax = 24 Å–1 while the first-reported Na K-edge EXAFS measurements have a spatial resolution corresponding to 2k = Qmax = 16 Å–1. Both provide an accurate measure of the shape and position of the first peak in the Na–O pair distribution function, gNaO(r). The measured Na–O distances of 2.384 ± 0.003 Å (XRD) and 2.37 ± 0.024 Å (EXAFS) are in excellentmore » agreement. These measurements show a much shorter Na–O distance than generally reported in the experimental literature (Na–Oavg ~ 2.44 Å) although the current measurements are in agreement with recent neutron diffraction measurements. The measured Na–O coordination number from XRD is 5.5 ± 0.3. The measured structure is compared with both classical and first-principles density functional theory (DFT) simulations. Both of the DFT-based methods, revPBE and BLYP, predict a Na–O distance that is too long by about 0.05 Å with respect to the experimental data (EXAFS and XRD). The inclusion of dispersion interactions (–D3 and –D2) significantly worsens the agreement with experiment by further increasing the Na–O distance by 0.07 Å. In contrast, the use of a classical Na–O Lennard-Jones potential with SPC/E water accurately predicts the Na–O distance as 2.39 Å although the Na–O peak is over-structured with respect to experiment.« less

  9. Stimulation of Na+/H+ Exchanger Isoform 1 Promotes Microglial Migration

    PubMed Central

    Shi, Yejie; Yuan, Hui; Kim, Dong; Chanana, Vishal; Baba, Akemichi; Matsuda, Toshio; Cengiz, Pelin; Ferrazzano, Peter; Sun, Dandan

    2013-01-01

    Regulation of microglial migration is not well understood. In this study, we proposed that Na+/H+ exchanger isoform 1 (NHE-1) is important in microglial migration. NHE-1 protein was co-localized with cytoskeletal protein ezrin in lamellipodia of microglia and maintained its more alkaline intracellular pH (pHi). Chemoattractant bradykinin (BK) stimulated microglial migration by increasing lamellipodial area and protrusion rate, but reducing lamellipodial persistence time. Interestingly, blocking NHE-1 activity with its potent inhibitor HOE 642 not only acidified microglia, abolished the BK-triggered dynamic changes of lamellipodia, but also reduced microglial motility and microchemotaxis in response to BK. In addition, NHE-1 activation resulted in intracellular Na+ loading as well as intracellular Ca2+ elevation mediated by stimulating reverse mode operation of Na+/Ca2+ exchange (NCXrev). Taken together, our study shows that NHE-1 protein is abundantly expressed in microglial lamellipodia and maintains alkaline pHi in response to BK stimulation. In addition, NHE-1 and NCXrev play a concerted role in BK-induced microglial migration via Na+ and Ca2+ signaling. PMID:23991215

  10. Sodium potassium adenosine triphosphatase (Na/K-ATPase) as a therapeutic target for uremic cardiomyopathy.

    PubMed

    Wang, Xiaoliang; Liu, Jiang; Drummond, Christopher A; Shapiro, Joseph I

    2017-05-01

    Clinically, patients with significant reductions in renal function present with cardiovascular dysfunction typically termed, uremic cardiomyopathy. It is a progressive series of cardiac pathophysiological changes, including left ventricular diastolic dysfunction and hypertrophy (LVH) which sometimes progress to left ventricular dilation (LVD) and systolic dysfunction in the setting of chronic kidney disease (CKD). Uremic cardiomyopathy is almost ubiquitous in patients afflicted with end stage renal disease (ESRD). Areas covered: This article reviews recent epidemiology, pathophysiology of uremic cardiomyopathy and provide a board overview of Na/K-ATPase research with detailed discussion on the mechanisms of Na/K-ATPase/Src/ROS amplification loop. We also present clinical and preclinical evidences as well as molecular mechanism of this amplification loop in the development of uremic cardiomyopathy. A potential therapeutic peptide that targets on this loop is discussed. Expert opinion: Current clinical treatment for uremic cardiomyopathy remains disappointing. Targeting the ROS amplification loop mediated by the Na/K-ATPase signaling function may provide a novel therapeutic target for uremic cardiomyopathy and related diseases. Additional studies of Na/K-ATPase and other strategies that regulate this loop will lead to new therapeutics.

  11. Sodium potassium adenosine triphosphatase (Na/K-ATPase) as a therapeutic target for uremic cardiomyopathy

    PubMed Central

    Wang, Xiaoliang; Liu, Jiang; Drummond, Christopher A

    2017-01-01

    Introduction Clinically, patients with significant reductions in renal function present with cardiovascular dysfunction typically termed, uremic cardiomyopathy. It is a progressive series of cardiac pathophysiological changes, including left ventricular diastolic dysfunction and hypertrophy (LVH) which sometimes progress to left ventricular dilation (LVD) and systolic dysfunction in the setting of chronic kidney disease (CKD). Uremic cardiomyopathy is almost ubiquitous in patients afflicted with end stage renal disease (ESRD). Areas covered This article reviews recent epidemiology, pathophysiology of uremic cardiomyopathy and provide a board overview of Na/K-ATPase research with detailed discussion on the mechanisms of Na/K-ATPase/Src/ROS amplification loop. We also present clinical and preclinical evidences as well as molecular mechanism of this amplification loop in the development of uremic cardiomyopathy. A potential therapeutic peptide that targets on this loop is discussed. Expert opinion Current clinical treatment for uremic cardiomyopathy remains disappointing. Targeting the ROS amplification loop mediated by the Na/K-ATPase signaling function may provide a novel therapeutic target for uremic cardiomyopathy and related diseases. Additional studies of Na/K-ATPase and other strategies that regulate this loop will lead to new therapeutics. PMID:28338377

  12. Na(+)/K(+)-ATPase immunoreactivity in branchial chloride cells of Oreochromis mossambicus exposed to copper.

    PubMed

    Dang, Z; Lock, R A; Flik, G; Wendelaar Bonga, S E

    2000-01-01

    Chloride cells were identified by Na(+)/K(+)-ATPase immunocytochemistry at the light and electron microscope levels in gills of freshwater tilapia Oreochromis mossambicus. Turnover of chloride cells was enhanced by exposing the fish to waterborne copper (3.2 micromol l(-)(1)) for 14 days, as indicated by a 38 % increase in cells expressing proliferating cell nuclear antigen (PCNA) relative to controls. The expression of PCNA was most marked in the central area of the filamental epithelium, from where the chloride cells are thought to originate and migrate. In control fish, chloride cells were associated exclusively with the filamental epithelium. In both controls and copper-exposed fish, two chloride cell populations were seen after Na(+)/K(+)-ATPase immunostaining. These probably represent subpopulations of newly emerged chloride cells: (1) strongly stained cells (mature chloride cells) in the filamental and lamellar epithelium and (2) weakly stained cells, identified by electron microscopy as apoptotic and necrotic chloride cells, mainly in the filamental epithelium. Absolute numbers of mature chloride cells fell, while necrotic and apoptotic chloride cell numbers increased, in copper-exposed fish. A strong correlation could be established for gill Na(+)/K(+)-ATPase specific activity and the number of strongly stained chloride cells in controls and copper-exposed fish and for Na(+)/K(+)-ATPase specific activity and total numbers of immunoreactive cells in copper-exposed fish owing to an increased incidence of weakly staining cells.

  13. COPPER Students - ELaNa IV

    NASA Image and Video Library

    2013-07-11

    The Close Orbiting Propellant Plume Elemental Recognition (COPPER) was developed by students from St. Louis University as a technology demonstration mission whose objective is to test the suitability of a commercially-available compact uncooled microbolometer (tiny infrared camera) array for scientific imagery of Earth in the long-wave infrared range (LWIR, 7-13 microns). Launched by NASA’s CubeSat Launch Initiative on the ELaNa IV mission as an auxiliary payload aboard the U.S. Air Force-led Operationally Responsive Space (ORS-3) Mission on November 19, 2013.

  14. CONCEPTUAL BASIS FOR NATURAL ATTENUATION (NA) ...

    EPA Pesticide Factsheets

    As used in enforcement actions at hazardous waste sites by U.S. EPA, monitored natural attenuation is a remedy fully equivalent to any other remedy. The acceptance of MNA is based on three lines of evidence: historical ground water and/or soil chemistry data that demonstrates a trend of declining contaminant concentration, 2. hydrogeologic and geochemical data that demonstrate NA processes and rates, and 3. Field or microcosm studies. MNA is appropriate as remedial approach only where it can be demonstrated to achieve remedial objectives within reasonable time frame, and meets the applicable remedy selection criteria for the particular regulatory program. To inform the public.

  15. The NA62 experiment at CERN

    NASA Astrophysics Data System (ADS)

    Piccini, Mauro

    2016-11-01

    The rare decays K → πvv¯ are excellent processes to make tests of new physics at the highest scale complementary to LHC thanks to their theoretically cleanness. The NA62 experiment at CERN SPS aims to collect of the order of 100 events in two years of data taking for the decay K+ → π+vv¯, keeping the background at the level of 10%. Part of the experimental apparatus has been commissioned during a technical run in 2012. The diverse and innovative experimental techniques will be explained and some preliminary results obtained during the 2014 pilot run will be reviewed.

  16. Status of the NA62 Experiment

    NASA Astrophysics Data System (ADS)

    Palladino, Vito

    2016-04-01

    The rare decays {{{K}}^ + } to {π ^ + }{{ν bar ν }} are excellent processes to make tests of new physics at the highest scale complementary to LHC thanks to their theoretically cleaness. The NA62 experiment at CERN SPS aims to collect of the order of 100 events in two years of data taking, keeping the background at the level of 10%. Part of the experimental apparatus has been commissioned during a technical run in 2012. The physics prospects and the status of the experiment will be reviewed after the commissioning run of 2014 and the data taking in 2015.

  17. The NA62 Gigatracker pixel detector system

    NASA Astrophysics Data System (ADS)

    Mazza, G.; Ceccucci, A.; Cortina, E.; Cotta Ramusino, A.; Dellacasa, G.; Fiorini, M.; Garbolino, S.; Jarron, P.; Kaplon, J.; Kluge, A.; Marchetto, F.; Martin, E.; Martoiu, S.; Noy, M.; Petrucci, F.; Riedler, P.; Rivetti, A.; Tiuraniemi, S.

    2010-05-01

    The silicon tracker for the NA62 experiment has to provide both a time resolution of 150 ps rms and a space resolution of about 100 μm rms. These challenging specifications require the development of a new readout electronics in order to address the problem of measuring the tracks arrival time with such a high channel density. Moreover, the high particle density (up to 1.5 MHz/mm2 in the center and 0.8-1 GHz in total) requires a high speed measurement and data transmission in order to keep the dead time below 1%.

  18. Subnitride chemistry: A first-principles study of the NaBa 3N, Na 5Ba 3N, and Na 16Ba 6N phases

    NASA Astrophysics Data System (ADS)

    Oliva, Josep M.

    2005-04-01

    An ab initio study on the electronic structure of the subnitrides NaBa 3N, Na 5Ba 3N, and Na 16Ba 6N is performed for the first time. The NaBa 3N and Na 5Ba 3N phases consist of infinite 1∞[NBa 6/2] strands composed of face-sharing NBa 6 octahedra surrounded by a "sea" of sodium atoms. The Na 16Ba 6N phase consist of discrete [NBa 6] octahedra arranged in a body-cubic fashion, surrounded by a "sea" of sodium atoms. Our calculations suggest that the title subnitrides are metals. Analysis of the electronic structure shows partial interaction of N(2s) with Ba(5 p) electrons in the lower energy region for NaBa 3N and Na 5Ba 3N. However, no dispersion is observed for the N(2s) and Ba(5 p) bands in the cubic phase Na 16Ba 6N. The metallic band below the Fermi level shows a strong mixing of N(2p), Ba(6 s), Ba(5 d), Ba(6 p), Na(3 s) and Na(3 p) orbitals. The metallic character in these nitrides stems from delocalized electrons corresponding to hybridized 5dl6sm6pn barium orbitals which interact with hybridized 3sn3pm sodium orbitals. Analysis of the electron density and electronic structure in these nitrides shows two different regions: a metallic matrix corresponding to the sodium atoms and the regions around them and heteropolar bonding between nitrogen and barium within the infinite 1∞[NBa 6/2] strands of the NaBa 3N and Na 5Ba 3N phases, and within the isolated [NBa 6] octahedra of the Na 16Ba 6N phase. The nitrogen atoms inside the strands and octahedra are negatively charged, the anionic character of nitrogens being larger in the isolated octahedra of the cubic phase Na 16Ba 6N, due to the lack of electron delocalization along one direction as opposed to the other phases. The sodium and barium atoms appear to be slightly negatively and positively charged, the latter to a larger extent. From the computed Ba-N overlap populations as well as the analysis of the contour maps of differences between total density and superposition of atomic densities, we suggest

  19. Interactions between Na+ channels and Na+-HCO3- cotransporters in the freshwater fish gill MR cell: a model for transepithelial Na+ uptake.

    PubMed

    Parks, Scott K; Tresguerres, Martin; Goss, Greg G

    2007-02-01

    Isolated mitochondria-rich (MR) cells from the rainbow trout gill epithelium were subjected to intracellular pH (pH(i)) imaging with the pH-sensitive dye BCECF-AM. MR cells were categorized into two distinct functional subtypes based on their ability to recover pH(i) from an NH(4)Cl-induced acidification in the absence of Na(+). An apparent link between resting pH(i) and Na(+)-independent pH(i) recovery was made. We observed a unique pH(i) acidification event that was induced by extracellular Na(+) addition. This further classified the mixed MR cell population into two functional subtypes: the majority of cells (77%) demonstrated the Na(+)-induced pH(i) acidification, whereas the minority (23%) demonstrated an alkalinization of pH(i) under the same circumstances. The focus of this study was placed on the Na(+)-induced acidification and pharmacological analysis via the use of amiloride and phenamil, which revealed that Na(+) uptake was responsible for the intracellular acidification. Further experiments revealed that pH(i) acidification could be abolished when Na(+) was allowed entry into the cell, but the activity of an electrogenic Na(+)-HCO(3)(-) cotransporter (NBC) was inhibited by DIDS. The electrogenic NBC activity was supported by a DIDS-sensitive, Na(+)-induced membrane potential depolarization as observed via imaging of the voltage-sensitive dye bis-oxonol. We also demonstrated NBC immunoreactivity via Western blotting and immunohistochemistry in gill tissue. We propose a model for transepithelial Na(+) uptake occurring via an apical Na(+) channel linked to a basolateral, electrogenic NBC in one subpopulation of MR cells.

  20. On the regulation of Na+/H+ and K+/H+ antiport in yeast mitochondria: evidence for the absence of an Na(+)-selective Na+/H+ antiporter.

    PubMed

    Welihinda, A A; Trumbly, R J; Garlid, K D; Beavis, A D

    1993-10-04

    Unlike mammalian mitochondria, yeast mitochondria swell spontaneously in both NaOAc and KOAc. This swelling reflects the activity of an electroneutral cation/H+ antiport pathway. Transport of neither salt is stimulated by depletion of endogenous divalent cations; however, it can be inhibited by addition of exogenous divalent cations (Mg2+ IC50 = 2.08 mM, Ca2+ IC50 = 0.82 mM). Transport of both Na+ and K+ can be completely inhibited by the amphiphilic amines propranolol (IC50 = 71 microM) and quinine (IC50 = 199 microM) with indistinguishable IC50 values. Dicyclohexylcarbodiimide inhibits with a second-order rate constant of 1.6 x 10(-4) (nmol DCCD/mg)-1 min-1 at 0 degrees C; however, with both Na+ and K+ inhibition reaches a maximum of about 46%. The remaining transport can still be inhibited by propranolol. Transport of both cations is sensitive to pH; yielding linear Hill plots and Dixon plots with a pIC50 value of 7.7 for both Na+ and K+. These properties are qualitatively the same as those of the non-selective K+/H+ antiporter of mammalian mitochondria. However, the remarkable similarity between the data obtained in Na+ and K+ media suggests that an antiporter akin to the Na(+)-selective Na+/H+ antiporter of mammalian mitochondria, which is inhibited by none of these agents, is absent in yeast. In an attempt to reveal the activity of a propranolol-insensitive Na(+)-selective antiporter, we compared the rates of Na+/H+ and K+/H+ antiport in the presence of sufficient propranolol to block the K+/H+ antiporter. Between pH 4.6 and 8.8 no difference could be detected. Consequently, we conclude that yeast mitochondria lack the typical Na(+)-selective Na+/H+ antiporter of mammalian mitochondria.

  1. Interfacial Reactions of Zn-Al Alloys with Na Addition on Cu Substrate During Spreading Test and After Aging Treatments

    NASA Astrophysics Data System (ADS)

    Gancarz, Tomasz; Pstruś, Janusz; Berent, Katarzyna

    2016-08-01

    Spreading tests for Cu substrate with Zn-Al eutectic-based alloys with 0.2, 0.5, and 1.0 wt.% of Na were studied using the sessile drop method in the presence of QJ201 flux. Spreading tests were performed for 1, 3, 8, 15, 30, and 60 min of contact, at the temperatures of 475, 500, 525, and 550 °C. After cleaning the flux residue from solidified samples, the spreading area of Zn-Al + Na on Cu was determined in accordance with ISO 9455-10:2013-03. Selected, solidified solder-substrate couples were cross-sectioned and subjected to scanning electron microscopy of the interfacial microstructure. The experiment was designed to demonstrate the effect of Na addition on the kinetics of formation and growth of CuZn, Cu5Zn8, and CuZn4 phases, which were identified using x-ray diffraction and energy-dispersive spectroscopy analysis. The addition of Na to eutectic Zn-Al caused the spreading area to decrease and the thickness of intermetallic compound layers at the interface to reduce. Samples after the spreading test at 500 °C for 1 min were subjected to aging for 1, 10, and 30 days at 120,170, and 250 °C. The greater thicknesses of IMC layers were obtained for a temperature of 250 °C. With increasing Na content in Zn-Al + Na alloys, the thickness reduced, which correlates to the highest value of activation energy for Zn-Al with 1% Na.

  2. [Effects of NaCl stress on Hippophae rhamnoides and Shepherdia argentea seedlings growth and photosynthetic characteristics].

    PubMed

    Qin, Jing; He, Kang-Ning; Tan, Guo-Dong; Wang, Zhan-Lin; Chen, Jing

    2009-04-01

    With two-year old seedlings of Hippophea rhamnoides and Shepherdia argentea as test materials, this paper studied their growth and photosynthetic characteristics under the stress of different concentration (0, 200, 400 and 600 mmol x L(-1)) NaCl. The results showed that the biomass and total leaf area per plant of H. rhamnoides and S. argentea seedlings decreased significantly with increasing NaCl concentration. Comparing with the control, the root/shoot ratio of H. rhamnoides and S. argentea seedlings under NaCl stress increased obviously, while the leaf mass per area (LMA) decreased slightly. When the NaCl concentration increased and the stress time prolonged, the net photosynthetic rate (P(n)), transpiration rate (T(r)), and stomatal conductance (G(s)) of H. rhamnoides and S. argentea seedlings declined markedly, the intercellular CO2 concentration (C(i)) increased after an initial decrease, whereas the water use efficiency (WUE) and stomatal limiting value (L(s)) decreased after an initial increase. The dynamic changes of G(s), C(i) and L(s) indicated that the decline of P(n) was mainly caused by the stomatal limitation in a short-term stress, and by non-stomatal limitation in a long-term stress. The poorer the salt tolerance of tree species and the higher the NaCl concentration, the earlier the transition from stomatal limitation to non-stomatal limitation would occur. As for H. rhamnoides, its morphological symptoms of salt injury appeared on the 10th day, and all of its seedlings were died on the 22th day under 600 mmol NaCl x L(-1) stress. In contrast, S. argentea could tolerate 600 mmol NaCl x L(-1) stress for above 30 days, illustrating that S. argentea, as an introduced tree species, had higher salt tolerance than H. rhamnoides, and could be planted widely in saline regions of China.

  3. POST-OPERATIONAL TREATMENT OF RESIDUAL NA COOLLANT IN EBR-2 USING CARBONATION

    SciTech Connect

    Sherman, S.; Knight, C.

    2011-03-08

    At the end of 2002, the Experimental Breeder Reactor Two (EBR-II) facility became a U.S. Resource Conservation and Recovery Act (RCRA) permitted site, and the RCRA permit1 compelled further treatment of the residual sodium in order to convert it into a less reactive chemical form and remove the by-products from the facility, so that a state of RCRA 'closure' for the facility may be achieved (42 U.S.C. 6901-6992k, 2002). In response to this regulatory driver, and in recognition of project budgetary and safety constraints, it was decided to treat the residual sodium in the EBR-II primary and secondary sodium systems using a process known as 'carbonation.' In early EBR-II post-operation documentation, this process is also called 'passivation.' In the carbonation process (Sherman and Henslee, 2005), the system containing residual sodium is flushed with humidified carbon dioxide (CO{sub 2}). The water vapor in the flush gas reacts with residual sodium to form sodium hydroxide (NaOH), and the CO{sub 2} in the flush gas reacts with the newly formed NaOH to make sodium bicarbonate (NaHCO{sub 3}). Hydrogen gas (H{sub 2}) is produced as a by-product. The chemical reactions occur at the exposed surface of the residual sodium. The NaHCO{sub 3} layer that forms is porous, and humidified carbon dioxide can penetrate the NaHCO{sub 3} layer to continue reacting residual sodium underneath. The rate of reaction is controlled by the thickness of the NaHCO{sub 3} surface layer, the moisture input rate, and the residual sodium exposed surface area. At the end of carbonation, approximately 780 liters of residual sodium in the EBR-II primary tank ({approx}70% of original inventory), and just under 190 liters of residual sodium in the EBR-II secondary sodium system ({approx}50% of original inventory), were converted into NaHCO{sub 3}. No bare surfaces of residual sodium remained after treatment, and all remaining residual sodium deposits are covered by a layer of NaHCO{sub 3}. From a

  4. Differential tolerance of 3 self-rooted Citrus limon cultivars to NaCl stress.

    PubMed

    Tsabarducas, V; Chatzistathis, T; Therios, I; Koukourikou-Petridou, M; Tananaki, C

    2015-12-01

    alleviated the harmful effect of NaCl stress, thus it is highly recommended for use by the growers in areas with salt problems. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  5. Wide area sensor network

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, Sanjoy; Nix, Tricia; Junker, Robert; Brentano, Josef; Khona, Dhiren

    2006-05-01

    The technical concept for this project has existed since the Chernobyl accident in 1986. A host of Eastern European nations have developed countrywide grid of sensors to monitor airborne radiation. The objective is to build a radiological sensor network for real-time monitoring of environmental radiation levels in order to provide data for warning, and consequentially the assessment of a nuclear event. A network of radiation measuring equipment consisting of gamma, neutron, alpha, and beta counters would be distributed over a large area (preferably on fire station roof tops) and connected by a wireless network to the emergency response center. The networks would be deployed in urban environments and would supply first responders and federal augmentation teams (including those from the U.S. Departments of Energy, Defense, Justice, and Homeland Security) with detailed, accurate information regarding the transport of radioactive environmental contaminants, so the agencies can provide a safe and effective response. A networked sensor capability would be developed, with fixed sensors deployed at key locations and in sufficient numbers, to provide adequate coverage for early warning, and input to post-event emergency response. An overall system description and specification will be provided, including detector characteristics, communication protocols, infrastructure and maintenance requirements, and operation procedures. The system/network can be designed for a specifically identified urban area, or for a general urban area scalable to cities of specified size. Data collected via the network will be transmitted directly to the appropriate emergency response center and shared with multiple agencies via the Internet or an Intranet. The data collected will be managed using commercial off - the - shelf Geographical Information System (GIS). The data will be stored in a database and the GIS software will aid in analysis and management of the data. Unique features of the

  6. Novel regulation of cell [Na(+)] in macula densa cells: apical Na(+) recycling by H-K-ATPase.

    PubMed

    Peti-Peterdi, János; Bebok, Zsuzsa; Lapointe, Jean-Yves; Bell, P Darwin

    2002-02-01

    Na-K-ATPase is the nearly ubiquitous enzyme that maintains low-Na(+), high-K(+) concentrations in cells by actively extruding Na(+) in exchange for K(+). The prevailing paradigm in polarized absorbing epithelial cells, including renal nephron segments and intestine, has been that Na-K-ATPase is restricted to the basolateral membrane domain, where it plays a prominent role in Na(+) absorption. We have found, however, that macula densa (MD) cells lack functionally and immunologically detectable amounts of Na-K-ATPase protein. In fact, these cells appear to regulate their cytosolic [Na(+)] via another member of the P-type ATPase family, the colonic form of H-K-ATPase, which is located at the apical membrane in these cells. We now report that this constitutively expressed apical MD colonic H-K-ATPase can function as a Na(H)-K-ATPase and regulate cytosolic [Na(+)] in a novel manner. This apical Na(+)-recycling mechanism may be important as part of the sensor function of MD cells and represents a new paradigm in cell [Na(+)] regulation.

  7. Penning and associative ionization in crossed-beam Na/Na collisions assisted by strong resonant laser fields

    SciTech Connect

    Weiner, J.; Polak-Dingels, P.

    1981-01-01

    We observe the production of Na/sub 2//sup +/ and Na/sup +/ arising from single collisions between crossed beams of sodium atoms when a laser field is tuned near the Na(3p /sup 2/P/sub 3/2/) and Na(3p /sup 2/P/sub 1/2/) transitions. Measurements of ion intensity vs laser intensity show that at moderately high power true laser-induced processes dominate over purely collisional effects. Relative intensity of mass-selected ions produced at either member of the Na resonance doublet shows conclusively that Na/sup +/ does not arise simply from photodissociation of Na/sub 2//sup +/ but must result from a direct, laser-induced collisional ionization.

  8. Vanadate sensitivity of Na+, K+-ATPase from Schistosoma mansoni and its modulation by Na+, K+ and Mg2+.

    PubMed

    Noel, F; Pardon, R S

    1989-01-01

    Vanadate inhibitory effects on Na+, K+-ATPases from carcass of Schistosoma mansoni and from lamb kidney outer medulla were compared in the presence of various concentrations of Na+, K+ and Mg2+. Depending on the ionic conditions, the schistosomal Na+, K+-ATPase was 2.4- to 175-fold less sensitive to vanadate than the lamb kidney enzyme. In 100 mM Na+, 3 mM K+ and 3 mM Mg2+, schistosomal Na+, K+-ATPase was surprisingly resistant to vanadate (I50 = 944 microM). The difference in vanadate sensitivity between schistosomal and lamb Na+, K+-ATPases may be due to a species difference in the efficacy of Na+, K+ and Mg2+ in promoting conformational changes between E1 and E2 forms of the enzyme.

  9. T-1 Training Area

    ScienceCinema

    None

    2016-07-12

    Another valuable homeland security asset at the NNSS is the T-1 training area, which covers more than 10 acres and includes more than 20 separate training venues. Local, County, and State first responders who train here encounter a variety of realistic disaster scenarios. A crashed 737 airliner lying in pieces across the desert, a helicopter and other small aircraft, trucks, buses, and derailed train cars are all part of the mock incident scene. After formal classroom education, first responders are trained to take immediate decisive action to prevent or mitigate the use of radiological or nuclear devices by terrorists. The Counterterrorism Operations Support Center for Radiological Nuclear Training conducts the courses and exercises providing first responders from across the nation with the tools they need to protect their communities. All of these elements provide a training experience that cannot be duplicated anywhere else in the country.

  10. T-1 Training Area

    SciTech Connect

    2014-11-07

    Another valuable homeland security asset at the NNSS is the T-1 training area, which covers more than 10 acres and includes more than 20 separate training venues. Local, County, and State first responders who train here encounter a variety of realistic disaster scenarios. A crashed 737 airliner lying in pieces across the desert, a helicopter and other small aircraft, trucks, buses, and derailed train cars are all part of the mock incident scene. After formal classroom education, first responders are trained to take immediate decisive action to prevent or mitigate the use of radiological or nuclear devices by terrorists. The Counterterrorism Operations Support Center for Radiological Nuclear Training conducts the courses and exercises providing first responders from across the nation with the tools they need to protect their communities. All of these elements provide a training experience that cannot be duplicated anywhere else in the country.

  11. Phoenix Work Area Animation

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on image for animation

    This animation from Sol 1 shows a mosaic of the Phoenix digging area in the Martian terrain. Phoenix scientists are very pleased with this view as the terrain features few rocks an optimal place for digging. The mast of the camera looks disjointed because the photos that comprise this mosaic were taken at different times of day. This video also show some of the lander's instrumentation.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  12. Mycetes and urban areas.

    PubMed

    Tampieri, M P

    2006-06-01

    Mycetes are ubiquitous organisms that can cause mycoses in human and animals. The role of animals in the epidemiology of human mycoses in urban areas is multiform, but here will be discuss only two features: A) animals as vectors of mycoses and B) animal substrates as growth factor of pathogenic fungi. A) Animals as vectors of mycoses: this role is important as zoofilic dermatophytes are very important agents of zoonosis; the urban dermatophytozoonoses are prevalent caused by Microsporum canis which is prevalent in cats and dogs. Cats are often asymptomatic carriers. The pattern of human dermatomycoses has changed in Italy during the past century: at the beginning of the century anthropophilic fungi were prevalent while at present the zoophilic fungi are the most important causes. B) Animal substrata as growth factor of pathogenic fungi: soil "animalization" (i.e., the addition of such debris as hair, skin scales, dropping and other organic matters) creates an optimal substratum for the growth and the multiplication of geophilic or saprophyitic fungi, such as Microsporum gypseum and Cryptococcus neoformans. The present human lifestyle, which favours a an overpopulation of birds, wild animals, domestic mammals and sinanthropic together with man in crowded areas seems to favour the formation of environments adapted to the abundant growth of some pathogenic fungi with consequent infection for man and animals. Finally, an environment heavily populated by fungi can cause allergic pulmonary reactions as well as reactions in other organs and tissues. The control of human and animal fungi, and the efficient use of a monitoring system require ample knowledge of mycological problems both in human and veterinary medicine and of efficient laboratories capable of resolving the needs of both disciplines. Close collaboration between veterinarians, doctors and mycologists is necessary in order to resolve health problems linked to mycosis.

  13. The Large Area Telescope

    SciTech Connect

    Michelson, Peter F.; /KIPAC, Menlo Park /Stanford U., HEPL

    2007-11-13

    The Large Area Telescope (LAT), one of two instruments on the Gamma-ray Large Area Space Telescope (GLAST) mission, is an imaging, wide field-of-view, high-energy pair-conversion telescope, covering the energy range from {approx}20 MeV to more than 300 GeV. The LAT is being built by an international collaboration with contributions from space agencies, high-energy particle physics institutes, and universities in France, Italy, Japan, Sweden, and the United States. The scientific objectives the LAT will address include resolving the high-energy gamma-ray sky and determining the nature of the unidentified gamma-ray sources and the origin of the apparently isotropic diffuse emission observed by EGRET; understanding the mechanisms of particle acceleration in celestial sources, including active galactic nuclei, pulsars, and supernovae remnants; studying the high-energy behavior of gamma-ray bursts and transients; using high-energy gamma-rays to probe the early universe to z {ge} 6; and probing the nature of dark matter. The components of the LAT include a precision silicon-strip detector tracker and a CsI(Tl) calorimeter, a segmented anticoincidence shield that covers the tracker array, and a programmable trigger and data acquisition system. The calorimeter's depth and segmentation enable the high-energy reach of the LAT and contribute significantly to background rejection. The aspect ratio of the tracker (height/width) is 0.4, allowing a large field-of-view and ensuring that nearly all pair-conversion showers initiated in the tracker will pass into the calorimeter for energy measurement. This paper includes a description of each of these LAT subsystems as well as a summary of the overall performance of the telescope.

  14. Corpus callosum abnormalities in medication-naïve adult patients with obsessive compulsive disorder.

    PubMed

    Jose, Dania; Narayanaswamy, Janardhanan C; Agarwal, Sri Mahavir; Kalmady, Sunil V; Venkatasubramanian, Ganesan; Reddy, Y C Janardhan

    2015-03-30

    Emerging evidence demonstrates widespread abnormalities involving white matter (WM) tracts connecting different cortical regions in obsessive-compulsive disorder (OCD). The corpus callosum (CC), the largest inter-hemispheric tract connecting the association cortices, has been shown to be affected in OCD. This study examines CC abnormalities in a large sample of medication-naïve OCD patients in comparison to matched healthy controls (HCs). We examined the mid-sagittal area of the CC in medication-naïve OCD patients (n=49) in comparison with age-, sex-, and handedness-matched HCs (n=38). Witelson's method was used to measure the sub-regions of the CC - namely, the genu, body, isthmus and splenium - with good inter-rater reliability. The area of the body of the CC and total CC area were significantly larger in OCD patients than in HCs after controlling for age, sex and intracranial area. The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) compulsion score had a significant negative correlation with the areas of the isthmus and splenium of the CC in addition to the total CC area. The region-specific differences in the body of the CC and the region-specific association of severity score with posterior regions of the CC might be indicative of the involvement of additional areas like the dorsolateral prefrontal cortex, posterior parietal areas, occipital and association cortices in OCD that extend beyond the conventional orbito-fronto-striatal circuitry that is often posited to be involved in OCD. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Effects of non-uniform root zone salinity on water use, Na+ recirculation, and Na+ and H+ flux in cotton

    PubMed Central

    Kong, Xiangqiang; Luo, Zhen; Dong, Hezhong; Eneji, A. Egrinya

    2012-01-01

    A new split-root system was established through grafting to study cotton response to non-uniform salinity. Each root half was treated with either uniform (100/100 mM) or non-uniform NaCl concentrations (0/200 and 50/150 mM). In contrast to uniform control, non-uniform salinity treatment improved plant growth and water use, with more water absorbed from the non- and low salinity side. Non-uniform treatments decreased Na+ concentrations in leaves. The [Na+] in the ‘0’ side roots of the 0/200 treatment was significantly higher than that in either side of the 0/0 control, but greatly decreased when the ‘0’ side phloem was girdled, suggesting that the increased [Na+] in the ‘0’ side roots was possibly due to transportation of foliar Na+ to roots through phloem. Plants under non-uniform salinity extruded more Na+ from the root than those under uniform salinity. Root Na+ efflux in the low salinity side was greatly enhanced by the higher salinity side. NaCl-induced Na+ efflux and H+ influx were inhibited by amiloride and sodium orthovanadate, suggesting that root Na+ extrusion was probably due to active Na+/H+ antiport across the plasma membrane. Improved plant growth under non-uniform salinity was thus attributed to increased water use, reduced leaf Na+ concentration, transport of excessive foliar Na+ to the low salinity side, and enhanced Na+ efflux from the low salinity root. PMID:22200663

  16. Synthesis of NaYF4, NaLuF4 and NaGdF4-based upconversion nanocrystals with hydro (solvo) thermal methods.

    PubMed

    Yin, Dongguang; Song, Kailin; Ou, Yangjuan; Wang, Chengcheng; Liu, Bing; Wu, Minghong

    2013-06-01

    Serials of NaYF4, NaLuF4 and NaGdF4-based nanocrystals have been synthesized successfully by solvothermal and hydrothermal, respectively. The properties of the products were characterized and compared. The nanocrystals prepared by hydrothermal method exhibited uniform hexagonal phase and large size, while the nanocrystals prepared by solvothermal method displayed high upconversion luminescence (UCL) and small size. The UCL intensities of the nanocrystals prepared by solvothermal method were higher than that of nanocrystals from hydrothermal method. Whether using solvothermal or hydrothermal method, the UCL intensities of the nanocrystals were in the sequence (from strong to weak) of NaLuF4:Gd/Yb/Tm, NaLuF4:Yb/Tm, NaGdF4:Yb/Tm, NaYF4:Gd/Yb/Tm and NaYF4:Yb/Tm, respectively. This is the first time to systematically compare three kinds of host-based nanocrystals, which are prepared by two different approaches with various lanthanide ions doped. This work could provide new insight into fabrication of upconversion nanocrystals with intense UCL and controllable morphology and size via using suitable doping ions, host materials and efficient approaches.

  17. NaSrMn2F7, NaCaFe2F7, and NaSrFe2F7: novel single crystal pyrochlore antiferromagnets

    NASA Astrophysics Data System (ADS)

    Sanders, M. B.; Krizan, J. W.; Plumb, K. W.; McQueen, T. M.; Cava, R. J.

    2017-02-01

    The crystal structures and magnetic properties of three previously unreported A2B2F7 pyrochlore materials, NaSrMn2F7, NaCaFe2F7, and NaSrFe2F7 are presented. In these compounds, either S  =  2Fe2+ or S  =  5/2Mn2+ is on the B site, while nonmagnetic Na and Ca (Na and Sr) are disordered on the A site. The materials, which were grown as crystals via the floating zone method, display high effective magnetic moments and large Curie-Weiss thetas. Despite these characteristics, no ordering transition is detected. However, freezing of the magnetic spins, characterized by peaks in the susceptibility or specific heat, is observed at very low temperatures. The empirical frustration index, f  =  -θ CW/T f, for the materials are 36 (NaSrMn2F7), 27 (NaSrFe2F7), and 19 (NaCaFe2F7). AC susceptibility, DC susceptibility, and heat capacity measurements are used to characterize the observed spin glass behavior. The results suggest that the compounds are frustrated pyrochlore antiferromagnets with weak bond disorder. The magnetic phenomena that these fluoride pyrochlores exhibit, in addition to their availability as relatively large single crystals, make them promising candidates for the study of geometric magnetic frustration.

  18. 100 Area D4 Project Building Completion Report - July 2007 to December 2008

    SciTech Connect

    M. T. Stankovich

    2009-04-15

    This report documents the decontamination, decommissioning, and demolition of the 105-NB, 163-N, 183-N, 183-NA, 183-NB, 183-NC, 184-N, 184-NA, 184-NB, 184-NC, 184-ND, 184-NE, 184-NF, 1312-N, 1330-N, 1705-N, 1705-NA, 1706-N, 1712-N, 1714-N, 1714-NA, 1714-NB, 1802-N, MO-050, MO-055, MO-358, MO-390, MO-900, MO-911, and MO-950 facilities in the 100 Area of the Hanford Site. The D4 activities for these facilities include utility disconnection, planning, characterization, engineering, removal of hazardous and radiological contaminated materials, equipment removal, decommissioning, deactivation, decontamination, demolition of the structure, and removal of the remaining slabs.

  19. NA-CORDEX: Overview and Sample Results

    NASA Astrophysics Data System (ADS)

    Bukovsky, Melissa; Mearns, Linda; Arritt, Raymond; Castro, Christopher; Chang, Hsin-I.; Christensen, Jens; Christensen, Ole; Frigon, Anne; Gutowski, William; Kjellström, Erik; Laprise, René; McGinnis, Seth; Nikulin, Grigory; Scinocca, John; Sushama, Laxmi; Winger, Katje

    2017-04-01

    The North American CORDEX program (NA-CORDEX) has produced a good number of projections of climate according to the first phase of the CORDEX program. These simulations are based on a wide range of regional and global climate models, and some matrices of combinations have resulted. The RCMs involved include: WRF, CanRCM4, CRCM5, RegCM4, RCA4, and HirHam5. Driving GCMs include: EC-EARTH, CanESM2, HadGEM2-ES, GFDL-ESM2M, MPI-ESM-LR. These GCMs nicely span the equilibrium climate sensitivity of the GCMs making up the CMIP5 suite of models. Simulations have been performed both at .44 and .22 spatial resolutions and often for both RCP8.5 and 4.5. We will present an update of the status of NA-CORDEX, an overview of the simulations, and some of the results for North America, focusing on the quality of the baseline climate simulations and the projections of precipitation and temperature.

  20. The NA62 GigaTracker

    NASA Astrophysics Data System (ADS)

    Aglieri Rinella, G.; Feito, D. Alvarez; Arcidiacono, R.; Biino, C.; Bonacini, S.; Ceccucci, A.; Chiozzi, S.; Gil, E. Cortina; Ramusino, A. Cotta; Degrange, J.; Fiorini, M.; Gamberini, E.; Gianoli, A.; Kaplon, J.; Kluge, A.; Mapelli, A.; Marchetto, F.; Minucci, E.; Morel, M.; Noël, J.; Noy, M.; Perktold, L.; Perrin-Terrin, M.; Petagna, P.; Petrucci, F.; Poltorak, K.; Romagnoli, G.; Ruggiero, G.; Velghe, B.; Wahl, H.

    2017-02-01

    The GigaTracker is a hybrid silicon pixel detector built for the NA62 experiment aiming at measuring the branching fraction of the ultra-rare kaon decay K+ →π+ ν ν bar at the CERN SPS. The detector has to track particles in a beam with a flux reaching 1.3 MHz/mm2 and provide single-hit timing with 200 ps RMS resolution for a total material budget of less than 0.5% X0 per station. The tracker comprises three 60.8 mm×27 mm stations installed in vacuum (∼10-6 mbar) and cooled with liquid C6F14 circulating through micro-channels etched inside a few hundred micron thick silicon plates. Each station is composed of a 200 μm thick silicon sensor read out by 2×5 custom 100 μm thick ASICs, called TDCPix. Each chip contains 40×45 asynchronous pixels, 300 μm×300 μm each and is instrumented with 100 ps bin time-to-digital converters. In order to cope with the high rate, the TDCPix is equipped with four 3.2 Gb/s serialisers sending out the data. We will describe the detector and the results from the 2014 and 2015 NA62 runs.

  1. Minimizing Load Effects on NA4 Gear Vibration Diagnostic Parameter

    NASA Technical Reports Server (NTRS)

    Dempsey, Paula J.; Zakrajsek, James J.

    2001-01-01

    NA4 is a vibration diagnostic parameter, developed by researchers at NASA Glenn Research Center, for health monitoring of gears in helicopter transmissions. The NA4 reacts to the onset of gear pitting damage and continues to react to the damage as it spreads. This research also indicates NA4 reacts similarly to load variations. The sensitivity of NA4 to load changes will substantially affect its performance on a helicopter gearbox that experiences continuously changing load throughout its flight regimes. The parameter NA4 has been used to monitor gear fatigue tests at constant load. At constant load, NA4 effectively detects the onset of pitting damage and tracks damage severity. Previous research also shows that NA4 reacts to changes in load applied to the gears in the same way it reacts to the onset of pitting damage. The method used to calculate NA4 was modified to minimize these load effects. The modified NA4 parameter was applied to four sets of experimental data. Results indicate the modified NA4 is no longer sensitive to load changes, but remains sensitive to pitting damage.

  2. Adsorbed or intercalated: Na on graphene/Ir(111)

    NASA Astrophysics Data System (ADS)

    Pervan, Petar; Lazić, Predrag

    2017-09-01

    Interaction of sodium with graphene (Gr) on Ir(111) was studied with the aim to resolve the issue of Na adsorption/intercalation kinetics. The system Na/Gr/Ir(111) was studied by means of angle-resolved photoemission spectroscopy, low-energy electron diffraction, and ab initio density functional theory (DFT) calculation. It has been found that at room temperature (RT) and low concentrations Na is dominantly adsorbed on graphene. At higher concentrations, an intercalation process sets in so that it is possible to observe the coexistence of these two states. Eventually, all Na atoms are found in the intercalated state as determined by exposure to oxygen. While adsorption of Na on graphene already intercalated by Na [Na/Gr/Na/Ir(111) system] at RT was not possible, we could observe Li adsorption through the increase of Dirac point binding energy. Li coadsorption strongly affects the binding energy of the iridium surface state as well. This finding was supported by DFT calculations of adsorption energy of Na and Li on bare and fully Na intercalated graphene.

  3. Elevated intracellular Na(+) concentrations in developing spinal neurons.

    PubMed

    Lindsly, Casie; Gonzalez-Islas, Carlos; Wenner, Peter

    2017-03-01

    Over 25 years ago it was first reported that intracellular chloride levels (Cl(-)in ) were higher in developing neurons than in maturity. This finding has had significant implications for understanding the excitability of developing networks and recognizing the underlying causes of hyperexcitability associated with disease and neural injury. While there is some evidence that intracellular sodium levels (Na(+)in ) change during the development of non-neural cells, it has largely been assumed that Na(+)in is the same in developing and mature neurons. Here, using the sodium indicator SBFI, we test this idea and find that Na(+)in is significantly higher in embryonic spinal motoneurons and interneurons than in maturity. We find that Na(+)in reaches ~ 60 mM in mid-embryonic development and is then reduced to ~ 30 mM in late embryonic development. By retrogradely labeling motoneurons with SBFI we can reliably follow Na(+)in levels in vitro for hours. Bursts of spiking activity, and blocking voltage-gated sodium channels did not influence observed motoneuron sodium levels. On the other hand, Na(+)in was reduced by blocking the Na(+) -K(+) -2Cl(-) cotransporter NKCC1, and was highly sensitive to changes in external Na(+) and a blocker of the Na(+) /K(+) ATPase. Our findings suggest that the Na(+) gradient is weaker in embryonic neuronal development and strengthens in maturity in a manner similar to that of Cl(-) .

  4. Hydrogen Sulfide Induced Disruption of Na+ Homeostasis in the Cortex

    PubMed Central

    Chao, Dongman; He, Xiaozhou; Yang, Yilin; Balboni, Gianfranco; Salvadori, Severo; Kim, Dong H.; Xia, Ying

    2012-01-01

    Maintenance of ionic balance is essential for neuronal functioning. Hydrogen sulfide (H2S), a known toxic environmental gaseous pollutant, has been recently recognized as a gasotransmitter involved in numerous biological processes and is believed to play an important role in the neural activities under both physiological and pathological conditions. However, it is unclear if it plays any role in maintenance of ionic homeostasis in the brain under physiological/pathophysiological conditions. Here, we report by directly measuring Na+ activity using Na+ selective electrodes in mouse cortical slices that H2S donor sodium hydrosulfide (NaHS) increased Na+ influx in a concentration-dependent manner. This effect could be partially blocked by either Na+ channel blocker or N-methyl-D-aspartate receptor (NMDAR) blocker alone or almost completely abolished by coapplication of both blockers but not by non-NMDAR blocker. These data suggest that increased H2S in pathophysiological conditions, e.g., hypoxia/ischemia, potentially causes a disruption of ionic homeostasis by massive Na+ influx through Na+ channels and NMDARs, thus injuring neural functions. Activation of delta-opioid receptors (DOR), which reduces Na+ currents/influx in normoxia, had no effect on H2S-induced Na+ influx, suggesting that H2S-induced disruption of Na+ homeostasis is resistant to DOR regulation and may play a major role in neuronal injury in pathophysiological conditions, e.g., hypoxia/ischemia. PMID:22474073

  5. Rydberg States of Na-doped Helium Nanodroplets

    NASA Astrophysics Data System (ADS)

    Drabbels, Marcel

    2008-03-01

    The dynamics of excited states of Na atoms deposited on the surface of helium nanodroplets has been investigated with velocity map ion imaging, photoelectron spectroscopy and time-of-flight mass-spectroscopy. For the first time, the excitation spectra of Na-doped helium nanodroplets corresponding to Rydberg states of Na atoms have been measured from the lowest excited 3p state up to the ionization threshold. All lines in the excitation spectra are shifted and broadened with respect to the corresponding atomic lines. In addition to bare Na* atoms also Na*HeN (N = 1-6) exciplexes are detected upon excitation. Photoelectron spectroscopy reveals the desorption of Na* not only in the initially excited states but also in lower lying states, indicating that relaxation plays an important role. The recorded velocity distributions show interesting characteristics: for the lowest states the mean kinetic energy of Na* increases linearly with excitation energy. The velocity distributions of Na*HeN exciplexes do not manifest such remarkable properties. The observations can be largely explained by assuming that the interaction of Na* with the helium nanodroplet can be described by the sum of Na*-He pair potentials.

  6. Modification of hybrid NaY/ZSM-5/IDC zeolite composite with exchanged Cu2+ and its application as ammonia gas sensor

    NASA Astrophysics Data System (ADS)

    Lisnawati, Elsita; Krisnandi, Yuni Krisyuningsih; Triyono, Djoko

    2017-03-01

    A Modified NaY/ZSM-5/IDC zeolite composite with Cu2+ has been succsessfully prepared on the surface of quartz based Interdigitated Capacitor (IDC). The ZSM-5 was synthesized with double template using hydrothermal method and NaY zeolite was synthesized using sol-gel method. Powder XRD patterns confirmed that structures were ZSM-5 and NaY zeolites. Surface area analysis using BET method are 472,27 m2/g with pore size 2,32 nm for mesoporous ZSM-5 and 392,81 m2/g with pore size 1,6 nm for microporous NaY zeolite. NaY/ZSM-5/IDC and Cu/NaY/ZSM-5/IDC prior ammonia gas sensor testing using Electrochemical Impedance Spectroscopy (EIS) method. The composite has different sensitivity in range concentration of ammonia 0-300 ppm. The Cu/NaY/ZSM5/IDC has higher sensitivity compared to NaY/ZSM5/IDC.

  7. Direct interaction of Na-azide with the KATP channel.

    PubMed

    Trapp, S; Ashcroft, F M

    2000-11-01

    1. The effects of the metabolic inhibitor sodium azide were tested on excised macropatches from Xenopus oocytes expressing cloned ATP-sensitive potassium (KATP) channels of the Kir6.2/SUR1 type. 2. In inside-out patches from oocytes expressing Kir6.2 delta C36 (a truncated form of Kir6.2 that expresses in the absence of SUR), intracellular Na-azide inhibited macroscopic currents with an IC50 of 11 mM. The inhibitory effect of Na-azide was mimicked by the same concentration of NaCl, but not by sucrose. 3. Na-azide and NaCl blocked Kir6.2/SUR1 currents with IC50 of 36 mM and 19 mM, respectively. Inhibition was abolished in the absence of intracellular Mg2+. In contrast, Kir6.2 delta C36 currents were inhibited by Na-azide both in the presence or absence of intracellular Mg2+. 4. Kir6.2/SUR1 currents were less sensitive to 3 mM Na-azide in the presence of MgATP. This apparent reduction in sensitivity is caused by a small activatory effect of Na-azide conferred by SUR. 5. We conclude that, in addition to its well-established inhibitory effect on cellular metabolism, which leads to activation of KATP channels in intact cells, intracellular Na-azide has direct effects on the KATP channel. Inhibition is intrinsic to Kir6.2, is mediated by Na+, and is modulated by SUR. There is also a small, ATP-dependent, stimulatory effect of Na-azide mediated by the SUR subunit. The direct effects of 3 mM Na-azide on KATP channels are negligible in comparison to the metabolic activation produced by the same Na-azide concentration.

  8. Theoretical calculation of low-lying states of NaAr and NaXe

    NASA Technical Reports Server (NTRS)

    Laskowski, B. C.; Langhoff, S. R.; Stallcop, J. R.

    1981-01-01

    Potential curves as well as dipole moments and linking transition moments are calculated for the ground X 2 Sigma + and low lying excited A 2 Pi, B 2 Sigma +, C 2 Sigma +, (4) 2 Sigma +, (2) 2 Pi and (1) 2 Delta states of NaAr and NaXe. Calculations are performed using a self-consistent field plus configuration-interaction procedure with the core electrons replaced by an ab initio effective core potential. The potential curves obtained are found to be considerably less repulsive than the semiempirical curves of Pascale and Vandeplanque (1974) and to agree well with existing experimental data, although the binding energies of those states having potential minima due to van der Waals interactions are underestimated. Emission bands are also calculated for the X 2 Sigma + - C 2 Sigma + excimer transitions of NaAr and NaXe using the calculated transition moments and potential curves, and shown to agree well with experiment on the short-wavelength side of the maximum.

  9. Decomposition Kinetics of Titania Slag in Eutectic NaOH-NaNO3 System

    NASA Astrophysics Data System (ADS)

    Wang, Dong; Wang, Zhi; Qi, Tao; Wang, Lina; Xue, Tianyan

    2016-02-01

    The decomposition kinetics and mechanism of titania slag in eutectic NaOH-NaNO3 system were studied in the temperature range 623 K to 723 K (350 °C to 450 °C). Decomposed products were examined using X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. It has been identified that the main product is Na2TiO3 and the decomposition kinetics of titania slag followed a shrinking unreacted core model. It is proposed that the chemical reaction process was the rate determining step with apparent activation energy of 62.4 kJ/mol. NaNO3 was mainly acted as oxygen carrier and mass transport agent to lower the viscosity of the system. The purity of TiO2 obtained in the product was up to 99.3 pct. A flow diagram to produce TiO2 and to recycle the media was proposed.

  10. 24Mg(p, α)21Na reaction study for spectroscopy of 21Na

    DOE PAGES

    Cha, S. M.; Chae, K. Y.; Kim, A.; ...

    2015-11-03

    The Mg-24(p, alpha)Na-21 reaction was measured at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory in order to better constrain the spins and parities of the energy levels in Na-21 for the astrophysically important F-17(alpha, p)Ne-20 reaction rate calculation. 31-MeV proton beams from the 25-MV tandem accelerator and enriched Mg-24 solid targets were used. When recoiling He-4 particles from the Mg-24(p, alpha)Na-21 reaction we used a highly segmented silicon detector array to detect them; it measured the yields of He-4 particles over a range of angles simultaneously. A observed a new level at 6661 ± 5 keVmore » in the present work. The extracted angular distributions for the first four levels of Na-21 and the results from distorted wave Born approximation (DWBA) calculations were compared to verify and extract the angular momentum transfer.« less

  11. NaTa03/MCM-48 composites for photocatalytic conversion of organic molecules

    NASA Astrophysics Data System (ADS)

    Senevirathne, K.; Xia, C.-K.; Adhikari, S. P.; Zhang, L.; Williams, R. T.; Lachgar, A.

    2016-10-01

    The synthesis, characterization, and photocatalytic activity of a series of NaTaO3/MCM-48 composite photocatalysts prepared by sol-gel method is reported. The composite catalysts were investigated by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and N2 adsorption-desorption porosimetry. Their photocatalytic activity for conversion of organic molecules was tested using p-nitroaniline as a model pollutant. The surface area was found to be in the order of 235-964 m2/g and 35-407 m2/g for photocatalysts calcined at 500 °C and 850 °C, respectively. The surface area was found to depend on the MCM silica content. The pore size for samples calcined at 500 °C ranges from 2.6-3.2 nm, and becomes significantly larger at 850 °C (12.6-30.0 nm) for most composites. All composites have been found to be photocatalytically active towardsp-nitroaniline conversion intop-phenylenediamine under uv- visible irradiation. The conversion of p-nitroaniline per weight of NaTaO3 in the composite photocatalysts is found to be higher than that of pristine NaTaO3. The composites lose 12% of their original activity after three consecutive catalytic cycles.

  12. Topography measurements of high NA aspherical microlenses by digital holographic microscopy with spherical illumination

    NASA Astrophysics Data System (ADS)

    Józwik, Michal; Mikuła, Marta; Kozacki, Tomasz; Kostencka, Julianna; Gorecki, Christophe

    2017-06-01

    In this contribution, we propose a method of digital holographic microscopy (DHM) that enables measurement of high numerical aperture spherical and aspherical microstructures of both concave and convex shapes. The proposed method utilizes reflection of the spherical illumination beam from the object surface and the interference with a spherical reference beam of the similar curvature. In this case, the NA of DHM is fully utilized for illumination and imaging of the reflected object beam. Thus, the system allows capturing the phase coming from larger areas of the quasi-spherical object and, therefore, offers possibility of high accuracy characterization of its surface even in the areas of high inclination. The proposed measurement procedure allows determining all parameters required for the accurate shape recovery: the location of the object focus point and the positions of the illumination and reference point sources. The utility of the method is demonstrated with characterization of surface of high NA focusing objects. The accuracy is firstly verified by characterization of a known reference sphere with low error of sphericity. Then, the method is applied for shape measurement of spherical and aspheric microlenses. The results provide a full-field reconstruction of high NA topography with resolution in the nanometer range. The surface sphericity is evaluated by the deviation from the best fitted sphere or asphere, and the important parameters of the measured microlens: e.g.: radius of curvature and conic constant.

  13. High surface area ThO/sub 2/ catalyst

    DOEpatents

    Colmenares, C.A.; Somorjai, G.A.; Maj, J.J.

    1983-06-21

    A ThO/sub 2/ catalyst having a high surface area of about 80 to 125m/sup 2//g is synthesized. The compound is synthesized by simultaneously mixing an aqueous solution of ThNO/sub 3/(NO/sub 3/)/sub 4/.4H/sub 2/O with an aqueous solution of Na/sub 2/CO/sub 3/.H/sub 2/O, to produce a solution and solid ThOCO/sub 3/. The solid ThOCO/sub 3/ is separated from the solution, and then calcined at a temperature of about 225 to 300/sup 0/C for about 40 to 55 hours to produce ThO/sub 2/. The ThO/sub 2/ catalyst produced includes Na present as a substitutional cation in an amount equal to about 5 to 10 at. %.

  14. CLOUD PEAK PRIMITIVE AREA AND ADJACENT AREAS, WYOMING.

    USGS Publications Warehouse

    Kiilsgaard, Thor H.; Patten, Lowell L.

    1984-01-01

    The results of a mineral survey of the Cloud Peak Primitive Area and adjacent areas in Wyoming indicated little promise for the occurrence of mineral resources. There are some prospect workings, particularly in the northern part of the area, but in none of them were there indications that ore had been mined. Samples from the workings, from nearby rocks and sediments from streams that drain the area did not yield any metal values of significance. The crystalline rocks that underlie the area do not contain oil and gas or coal, products that are extracted from the younger rocks that underlie basins on both sides of the study area.

  15. Regulation of persistent Na current by interactions between beta subunits of voltage-gated Na channels.

    PubMed

    Aman, Teresa K; Grieco-Calub, Tina M; Chen, Chunling; Rusconi, Raffaella; Slat, Emily A; Isom, Lori L; Raman, Indira M

    2009-02-18

    The beta subunits of voltage-gated Na channels (Scnxb) regulate the gating of pore-forming alpha subunits, as well as their trafficking and localization. In heterologous expression systems, beta1, beta2, and beta3 subunits influence inactivation and persistent current in different ways. To test how the beta4 protein regulates Na channel gating, we transfected beta4 into HEK (human embryonic kidney) cells stably expressing Na(V)1.1. Unlike a free peptide with a sequence from the beta4 cytoplasmic domain, the full-length beta4 protein did not block open channels. Instead, beta4 expression favored open states by shifting activation curves negative, decreasing the slope of the inactivation curve, and increasing the percentage of noninactivating current. Consequently, persistent current tripled in amplitude. Expression of beta1 or chimeric subunits including the beta1 extracellular domain, however, favored inactivation. Coexpressing Na(V)1.1 and beta4 with beta1 produced tiny persistent currents, indicating that beta1 overcomes the effects of beta4 in heterotrimeric channels. In contrast, beta1(C121W), which contains an extracellular epilepsy-associated mutation, did not counteract the destabilization of inactivation by beta4 and also required unusually large depolarizations for channel opening. In cultured hippocampal neurons transfected with beta4, persistent current was slightly but significantly increased. Moreover, in beta4-expressing neurons from Scn1b and Scn1b/Scn2b null mice, entry into inactivated states was slowed. These data suggest that beta1 and beta4 have antagonistic roles, the former favoring inactivation, and the latter favoring activation. Because increased Na channel availability may facilitate action potential firing, these results suggest a mechanism for seizure susceptibility of both mice and humans with disrupted beta1 subunits.

  16. [Na] and [K] dependence of the Na/K pump current-voltage relationship in guinea pig ventricular myocytes

    PubMed Central

    1989-01-01

    Na/K pump current was determined between -140 and +60 mV as steady- state, strophanthidin-sensitive, whole-cell current in guinea pig ventricular myocytes, voltage-clamped and internally dialyzed via wide- tipped pipettes. Solutions were designed to minimize all other components of membrane current. A device for exchanging the solution inside the pipette permitted investigation of Na/K pump current-voltage (I-V) relationships at several levels of pipette [Na] [( Na]pip) in a single cell; the effects of changes in external [Na] [( Na]o) or external [K] [( K]o) were also studied. At 50 mM [Na]pip, 5.4 mM [K]o, and approximately 150 mM [Na]o, Na/K pump current was steeply voltage dependent at negative potentials but was approximately constant at positive potentials. Under those conditions, reduction of [Na]o enhanced pump current at negative potentials but had little effect at positive potentials: at zero [Na]o, pump current was only weakly voltage dependent. At 5.4 mM [K]o and approximately 150 mM [Na]o, reduction of [Na]pip from 50 mM scaled down the sigmoid pump I-V relationship and shifted it slightly to the right (toward more positive potentials). Pump current at 0 mV was activated by [Na]pip according to the Hill equation with best-fit K0.5 approximately equal to 11 mM and Hill coefficient nH approximately equal to 1.4. At zero [Na]o, reduction of [Na]pip seemed to simply scale down the relatively flat pump I-V relationship: Hill fit parameters for pump activation by [Na]pip at 0 mV were K0.5 approximately equal to 10 mM, nH approximately equal to 1.4. At 50 mM [Na]pip and high [Na]o, reduction of [K]o from 5.4 mM scaled down the sigmoid I-V relationship and shifted it slightly to the right: at 0 mV, K0.5 approximately equal to 1.5 mM and nH approximately equal to 1.0. At zero [Na]o, lowering [K]o simply scaled down the flat pump I-V relationships yielding, at 0 mV, K0.5 approximately equal to 0.2 mM, nH approximately equal to 1.1. The voltage

  17. Catecholamine-induced transport systems in trout erythrocyte. Na+/H+ countertransport or NaCl cotransport?

    PubMed Central

    1986-01-01

    It has previously been shown (Baroin, A., F. Garcia-Romeu, T. Lamarre, and R. Motais. 1984a, b. Journal of Physiology. 350:137, 356:21; Mahe, Y., F. Garcia-Romeu, and R. Motais. 1985. European Journal of Pharmacology. 116:199) that the addition of catecholamines to an isotonic suspension of nucleated red blood cells of the rainbow trout first stimulates a cAMP-dependent, amiloride-sensitive Na+/H+ exchange. This stimulation seems to be transient. It is followed by a more permanent activation of a coupled entry of Na+ and Cl-, which is inhibited by amiloride but also by inhibitors of band 3 protein (DIDS, furosemide, niflumic acid). The coupled entry of Na+ and Cl- could therefore result from the parallel and simultaneous exchange of Na+out for H+in (via the cAMP-dependent Na+/H+ antiporter) and Cl- out for HCO3- in (via the anion exchange system located in band 3 protein). However, in view of the following arguments, it had been proposed that NaCl uptake does not proceed by the double-exchanger system but via an NaCl cotransport: (a) Na+ entry requires Cl- as anion (in NO3- medium, the Na uptake is strongly inhibited, whereas NO3- is an extremely effective substitute for Cl- in the anion exchange system); (b) Na uptake is not significantly affected by the presence of HCO3- in the suspension medium despite the fact that in red cells, Cl-/HCO3- exchange occurs more readily than the exchanges of Cl- for basic equivalents in a theoretically CO2-free medium (the so-called Cl-/OH- exchanges). The purpose of the present paper was a reassessment of the two models by using monensin, an ionophore allowing Na+/H+ exchange. From this study, it appears that NaCl entry results from the simultaneous functioning of the Na+/H+ antiporter and the anion exchange system. The apparent Cl dependence is explained by the fact that, in these erythrocytes, NO3- clearly inhibits the turnover rate of the Na+/H+ antiporter. As Na+/H+ exchange is the driving component in the salt uptake process

  18. Large area Czochralski silicon

    NASA Technical Reports Server (NTRS)

    Rea, S. N.; Gleim, P. S.

    1977-01-01

    The overall cost effectiveness of the Czochralski process for producing large-area silicon was determined. The feasibility of growing several 12 cm diameter crystals sequentially at 12 cm/h during a furnace run and the subsequent slicing of the ingot using a multiblade slurry saw were investigated. The goal of the wafering process was a slice thickness of 0.25 mm with minimal kerf. A slice + kerf of 0.56 mm was achieved on 12 cm crystal using both 400 grit B4C and SiC abrasive slurries. Crystal growth experiments were performed at 12 cm diameter in a commercially available puller with both 10 and 12 kg melts. Several modifications to the puller hoz zone were required to achieve stable crystal growth over the entire crystal length and to prevent crystallinity loss a few centimeters down the crystal. The maximum practical growth rate for 12 cm crystal in this puller design was 10 cm/h, with 12 to 14 cm/h being the absolute maximum range at which melt freeze occurred.

  19. AREA RADIATION MONITOR

    DOEpatents

    Manning, F.W.; Groothuis, S.E.; Lykins, J.H.; Papke, D.M.

    1962-06-12

    S>An improved area radiation dose monitor is designed which is adapted to compensate continuously for background radiation below a threshold dose rate and to give warning when the dose integral of the dose rate of an above-threshold radiation excursion exceeds a selected value. This is accomplished by providing means for continuously charging an ionization chamber. The chamber provides a first current proportional to the incident radiation dose rate. Means are provided for generating a second current including means for nulling out the first current with the second current at all values of the first current corresponding to dose rates below a selected threshold dose rate value. The second current has a maximum value corresponding to that of the first current at the threshold dose rate. The excess of the first current over the second current, which occurs above the threshold, is integrated and an alarm is given at a selected integrated value of the excess corresponding to a selected radiation dose. (AEC)

  20. Coordinated regulation of cardiac Na(+)/Ca (2+) exchanger and Na (+)-K (+)-ATPase by phospholemman (FXYD1).

    PubMed

    Cheung, Joseph Y; Zhang, Xue-Qian; Song, Jianliang; Gao, Erhe; Chan, Tung O; Rabinowitz, Joseph E; Koch, Walter J; Feldman, Arthur M; Wang, JuFang

    2013-01-01

    Phospholemman (PLM) is the founding member of the FXYD family of regulators of ion transport. PLM is a 72-amino acid protein consisting of the signature PFXYD motif in the extracellular N terminus, a single transmembrane (TM) domain, and a C-terminal cytoplasmic tail containing three phosphorylation sites. In the heart, PLM co-localizes and co-immunoprecipitates with Na(+)-K(+)-ATPase, Na(+)/Ca(2+) exchanger, and L-type Ca(2+) channel. The TM domain of PLM interacts with TM9 of the α-subunit of Na(+)-K(+)-ATPase, while its cytoplasmic tail interacts with two small regions (spanning residues 248-252 and 300-304) of the proximal intracellular loop of Na(+)/Ca(2+) exchanger. Under stress, catecholamine stimulation phosphorylates PLM at serine(68), resulting in relief of inhibition of Na(+)-K(+)-ATPase by decreasing K(m) for Na(+) and increasing V(max), and simultaneous inhibition of Na(+)/Ca(2+) exchanger. Enhanced Na(+)-K(+)-ATPase activity lowers intracellular Na(+), thereby minimizing Ca(2+) overload and risks of arrhythmias. Inhibition of Na(+)/Ca(2+) exchanger reduces Ca(2+) efflux, thereby preserving contractility. Thus, the coordinated actions of PLM during stress serve to minimize arrhythmogenesis and maintain inotropy. In acute cardiac ischemia and chronic heart failure, either expression or phosphorylation of PLM or both are altered. PLM regulates important ion transporters in the heart and offers a tempting target for development of drugs to treat heart failure.

  1. Na emission and bubble instability in single-bubble sonoluminescence.

    PubMed

    Choi, Pak-Kon; Takumori, Keisuke; Lee, Hyang-Bok

    2017-09-01

    Na emission in single-bubble sonoluminescence (SBSL) was observed from 0.1mM sodium dodecyl sulfate (SDS) solution containing a dissolved noble gas at a low acoustic pressure, at which a continuous spectral component was negligible. High-speed shadowgraph movies were captured at a frame rate of 30,000fps, which indicated that bubble dancing is responsible for the Na emission. The measured bubble path length was well correlated with the Na intensity. The disintegration of a daughter bubble followed by immediate coalescence was frequently observed, which may have been the cause of the bubble dancing. A comparison of the Na spectra obtained in SBSL and multibubble SL showed that the conditions under which Na emission is generated are twofold. A narrow component was observed in the Na spectrum in SBSL, while narrow and broad components were observed in MBSL. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. The paranodal cytoskeleton clusters Na(+) channels at nodes of Ranvier.

    PubMed

    Amor, Veronique; Zhang, Chuansheng; Vainshtein, Anna; Zhang, Ao; Zollinger, Daniel R; Eshed-Eisenbach, Yael; Brophy, Peter J; Rasband, Matthew N; Peles, Elior

    2017-01-30

    A high density of Na(+) channels at nodes of Ranvier is necessary for rapid and efficient action potential propagation in myelinated axons. Na+ channel clustering is thought to depend on two axonal cell adhesion molecules that mediate interactions between the axon and myelinating glia at the nodal gap (i.e., NF186) and the paranodal junction (i.e., Caspr). Here we show that while Na(+) channels cluster at nodes in the absence of NF186, they fail to do so in double conditional knockout mice lacking both NF186 and the paranodal cell adhesion molecule Caspr, demonstrating that a paranodal junction-dependent mechanism can cluster Na(+) channels at nodes. Furthermore, we show that paranode-dependent clustering of nodal Na(+) channels requires axonal βII spectrin which is concentrated at paranodes. Our results reveal that the paranodal junction-dependent mechanism of Na(+)channel clustering is mediated by the spectrin-based paranodal axonal cytoskeleton.

  3. Pyrophosphate-Fueled Na+ and H+ Transport in Prokaryotes

    PubMed Central

    Malinen, Anssi M.; Luoto, Heidi H.

    2013-01-01

    SUMMARY In its early history, life appeared to depend on pyrophosphate rather than ATP as the source of energy. Ancient membrane pyrophosphatases that couple pyrophosphate hydrolysis to active H+ transport across biological membranes (H+-pyrophosphatases) have long been known in prokaryotes, plants, and protists. Recent studies have identified two evolutionarily related and widespread prokaryotic relics that can pump Na+ (Na+-pyrophosphatase) or both Na+ and H+ (Na+,H+-pyrophosphatase). Both these transporters require Na+ for pyrophosphate hydrolysis and are further activated by K+. The determination of the three-dimensional structures of H+- and Na+-pyrophosphatases has been another recent breakthrough in the studies of these cation pumps. Structural and functional studies have highlighted the major determinants of the cation specificities of membrane pyrophosphatases and their potential use in constructing transgenic stress-resistant organisms. PMID:23699258

  4. Chemical and morphological changes during olivine carbonation for CO2 storage in the presence of NaCl and NaHCO3.

    PubMed

    Gadikota, Greeshma; Matter, Juerg; Kelemen, Peter; Park, Ah-Hhyung Alissa

    2014-03-14

    The increasing concentrations of CO2 in the atmosphere are attributed to the rising consumption of fossil fuels for energy generation around the world. One of the most stable and environmentally benign methods of reducing atmospheric CO2 is by storing it as thermodynamically stable carbonate minerals. Olivine ((Mg,Fe)2SiO4) is an abundant mineral that reacts with CO2 to form Mg-carbonate. The carbonation of olivine can be enhanced by injecting solutions containing CO2 at high partial pressure into olivine-rich formations at high temperatures, or by performing ex situ mineral carbonation in a reactor system with temperature and pressure control. In this study, the effects of NaHCO3 and NaCl, whose roles in enhanced mineral carbonation have been debated, were investigated in detail along with the effects of temperature, CO2 partial pressure and reaction time for determining the extent of olivine carbonation and its associated chemical and morphological changes. At high temperature and high CO2 pressure conditions, more than 70% olivine carbonation was achieved in 3 hours in the presence of 0.64 M NaHCO3. In contrast, NaCl did not significantly affect olivine carbonation. As olivine was dissolved and carbonated, its pore volume, surface area and particle size were significantly changed and these changes influenced subsequent reactivity of olivine. Thus, for both long-term simulation of olivine carbonation in geologic formations and the ex situ reactor design, the morphological changes of olivine during its reaction with CO2 should be carefully considered in order to accurately estimate the CO2 storage capacity and understand the mechanisms for CO2 trapping by olivine.

  5. Structural and optical properties of Na doped ZnO nanocrystals: Application to solar photocatalysis

    NASA Astrophysics Data System (ADS)

    Tabib, Asma; Bouslama, Wiem; Sieber, Brigitte; Addad, Ahmed; Elhouichet, Habib; Férid, Mokhtar; Boukherroub, Rabah

    2017-02-01

    Na doped ZnO nanocrystals (NCs) were successfully produced by sol-gel process and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high resolution TEM (HRTEM), Raman scattering, UV-vis diffuse reflectance spectroscopy and photoluminescence (PL). XRD analysis indicated that all the prepared samples present pure hexagonal wurtzite structure without any Na related phases. The lattice distortion, calculated using Williamson hall equation, induces stress and a reduction of NCs size from 71.4 to 24.5 nm. TEM images showed NCs with hexagonal shape and a rather uniform size distribution. The selected area electron diffraction (SAED) patterns confirmed the high crystal quality along the <101> direction and is consistent with the hexagonal wurtzite structure of ZnO. The Raman spectra are dominated by E2high mode of ZnO. High Na doping shows the occurrence of anomalous local vibrational Raman modes close to 270 and 513 cm-1 that are related to intrinsic host lattice defects and distortion, respectively. Optical band gap was found to vary with Na content. Photoluminescence (PL) spectra indicate the presence of a high density of defects in ZnO NCs which are mainly oxygen vacancies. Finally, the obtained NCs were used as a photocatalyst to degrade Rhodamine B (RhB) in solution, under solar irradiation. Na doping enhances the photocatalytic activity of ZnO NCs till an optimum concentration of 0.5% where a full degradation was observed after 120 min of sun light irradiation. Furthermore, this sample presents a good cycling stability and reusability. Based on scavangers test, it was found that both superoxide and hydroxyl oxidizing radicals are mainly actives.

  6. Control of GaN crystal habit by solution stirring in the Na-flux method

    NASA Astrophysics Data System (ADS)

    Murakami, Kosuke; Imade, Mamoru; Imanishi, Masayuki; Honjo, Masatomo; Imabayashi, Hiroki; Matsuo, Daisuke; Nakamura, Kosuke; Maruyama, Mihoko; Yoshimura, Masashi; Mori, Yusuke

    2017-01-01

    In our previous study, we succeeded in fabricating low-curvature GaN wafers with low dislocation density by the Na-flux coalescence growth technique. However, the crystals consisted of many pyramidal grains with (10\\bar{1}1) facets, leading to an increase in the oxygen concentration in the crystal, an increase in the lattice constant, and blackening. In this study, we attempted to improve the crystal habit of the GaN crystals by employing a solution-stirring technique in the coalescence growth on multipoint seeds. Scanning electron microscope images indicated that the c-face area became larger by increasing the stirring rate and growth period. We concluded that solution stirring in the Na-flux coalescence growth technique is an effective approach to improve the crystal habit and uniformize the lattice constant of GaN crystals.

  7. Groundwater quality assessment plan for the 1324-N/NA Site: Phase 1 (first determination)

    SciTech Connect

    Hartman, M.J.

    1998-05-01

    The 1324-N Surface Impoundment and 1324-NA Percolation Pond (1324-N/NA Site) are treatment/storage/disposal sites regulated under the Resource Conservation and Recovery Act of 1976 (RCRA). They are located in the 100-N Area of the Hanford Site, and were used to treat and dispose of corrosive waste from a water treatment plant. Groundwater monitoring under an interim-status detection program compared indicator parameters from downgradient wells to background values established from an upgradient well. One of the indicator parameters, total organic carbon (TOC), exceeded its background value in one downgradient well, triggering an upgrade from a detection program to an assessment program. This plan presents the first phase of the assessment program.

  8. Comparison of titanium soaked in 5 M NaOH or 5 M KOH solutions

    PubMed Central

    Kim, Christina; Kendall, Matthew R.; Miller, Matthew A.; Long, Courtney L.; Larson, Preston R.; Humphrey, Mary Beth; Madden, Andrew S.; Tas, A. Cuneyt

    2012-01-01

    Commercially pure titanium plates/coupons and pure titanium powders were soaked for 24 h in 5 M NaOH and 5 M KOH solutions, under identical conditions, over the temperature range of 37° to 90°C. Wettability of the surfaces of alkali-treated cpTi coupons were studied by using contact angle goniometry. cpTi coupons soaked in 5 M NaOH or 5 M KOH solutions were found to have hydrophilic surfaces. Hydrous alkali titanate nanofibers and nanotubes were identified with SEM/EDXS and grazing incidence XRD. Surface areas of Ti powders increased >50–220 times, depending on the treatment, when soaked in the above solutions. A solution was developed to coat amorphous calcium phosphate, instead of hydroxyapatite, on Ti coupon surfaces. In vitro cell culture tests were performed with osteoblast-like cells on the alkali-treated samples. PMID:23565038

  9. Eagle Crater Traverse Area

    NASA Technical Reports Server (NTRS)

    2004-01-01

    high in hematite content compared to other soils in the crater. 'Neopolitan' lies on a triple boundary of a light soil unit, a dark soil unit and an airbag bounce mark. 'Mudpie' was chosen to represent typical soils on the lower part of the crater that are relatively far from the outcrop. 'Meringue' is a unique rippled area near the lander that features patches of 'whitish' material in between the ripples. 'Black Forest' is another upper crater soil unit but is low in hematite content based on data from the miniature thermal emission spectrometer. It also differs in appearance from the lower crater soils based on panoramic and navigation camera images. Arrows point to the area where Opportunity first attempted to exit the crater and the alternate route it ultimately took to reach the plains.

  10. Simulation of Na D emission near Europa during eclipse

    USGS Publications Warehouse

    Cassidy, T.A.; Johnson, R.E.; Geissler, P.E.; Leblanc, F.

    2008-01-01

    The Cassini imaging science subsystem observed Europa in eclipse during Cassini's Jupiter flyby. The disk-resolved observations revealed a spatially nonuniform emission in the wavelength range of 200-1050 nm (clear filters). By building on observations and simulations of Europa's Na atmosphere and torus we find that electron-excited Na in Europa's tenuous atmosphere can account for the observed emission if the Na is ejected preferentially from Europa's dark terrain. Copyright 2008 by the American Geophysical Union.

  11. Recent results and prospects for NA62 experiment

    NASA Astrophysics Data System (ADS)

    Martellotti, Silvia; Aglieri Rinella, G.; Aliberti, R.; Ambrosino, F.; Ammendola, R.; Angelucci, B.; Antonelli, A.; Anzivino, G.; Arcidiacono, R.; Azhinenko, I.; Balev, S.; Barbanera, M.; Bendotti, J.; Biagioni, A.; Bician, L.; Biino, C.; Bizzeti, A.; Blazek, T.; Blik, A.; Bloch-Devaux, B.; Bolotov, V.; Bonaiuto, V.; Boretto, M.; Bragadireanu, M.; Britton, D.; Britvich, G.; Brunetti, M. B.; Bryman, D.; Bucci, F.; Butin, F.; Capitolo, E.; Capoccia, C.; Capussela, T.; Cassese, A.; Catinaccio, A.; Cecchetti, A.; Ceccucci, A.; Cenci, P.; Cerny, V.; Cerri, C.; Checcucci, B.; Chikilev, O.; Chiozzi, S.; Ciaranfi, R.; Collazuol, G.; Conovaloff, A.; Cooke, P.; Cooper, P.; Corradi, G.; Cortina Gil, E.; Costantini, F.; Cotorobai, F.; Cotta Ramusino, A.; Coward, D.; D'Agostini, G.; Dainton, J.; Dalpiaz, P.; Danielsson, H.; Degrange, J.; De Simone, N.; Di Filippo, D.; Di Lella, L.; Di Lorenzo, S.; Dixon, N.; Doble, N.; Dobrich, B.; Duk, V.; Elsha, V.; Engelfried, J.; Enik, T.; Estrada, N.; Falaleev, V.; Fantechi, R.; Fascianelli, V.; Federici, L.; Fedotov, S.; Fiorini, M.; Fry, J.; Fu, J.; Fucci, A.; Fulton, L.; Gallorini, S.; Galeotti, S.; Gamberini, E.; Gatignon, L.; Georgiev, G.; Gianoli, A.; Giorgi, M.; Giudici, S.; Glonti, L.; Goncalves Martins, A.; Gonnella, F.; Goudzovski, E.; Guida, R.; Gushchin, E.; Hahn, F.; Hallgren, B.; Heath, H.; Herman, F.; Husek, T.; Hutanu, O.; Hutchcroft, D.; Iacobuzio, L.; Iacopini, E.; Imbergamo, E.; Jamet, O.; Jarron, P.; Jones, E.; Kampf, K.; Kaplon, J.; Kekelidze, V.; Kholodenko, S.; Khoriauli, G.; Khotyantsev, A.; Khudyakov, A.; Kiryushin, Yu.; Kleimenova, A.; Kleinknecht, K.; Kluge, A.; Koval, M.; Kozhuharov, V.; Krivda, M.; Kucerova, Z.; Kudenko, Y.; Kunze, J.; Lamanna, G.; Latino, G.; Lazzeroni, C.; Lehmann-Miotto, G.; Lenci, R.; Lenti, M.; Leonardi, E.; Lichard, P.; Lietava, R.; Litov, L.; Lollini, R.; Lomidze, D.; Lonardo, A.; Lupi, M.; Lurkin, N.; McCormick, K.; Madigozhin, D.; Maire, G.; Mandeiro, C.; Mannelli, I.; Mannocchi, G.; Mapelli, A.; Marchetto, F.; Marchevski, R.; Martellotti, S.; Massarotti, P.; Massri, K.; Matak, P.; Maurice, E.; Mefodev, A.; Menichetti, E.; Minucci, E.; Mirra, M.; Misheva, M.; Molokanova, N.; Morant, J.; Morel, M.; Moulson, M.; Movchan, S.; Munday, D.; Napolitano, M.; Neri, I.; Newson, F.; Norton, A.; Noy, M.; Nuessle, G.; Numao, T.; Obraztsov, V.; Ostankov, A.; Padolski, S.; Page, R.; Palladino, V.; Paoluzzi, G.; Parkinson, C.; Pedreschi, E.; Pepe, M.; Perez Gomez, F.; Perrin-Terrin, M.; Peruzzo, L.; Petrov, P.; Petrucci, F.; Piandani, R.; Piccini, M.; Pietreanu, D.; Pinzino, J.; Polenkevich, I.; Pontisso, L.; Potrebenikov, Yu.; Protopopescu, D.; Raffaelli, F.; Raggi, M.; Riedler, P.; Romano, A.; Rubin, P.; Ruggiero, G.; Russo, V.; Ryjov, V.; Salamon, A.; Salina, G.; Samsonov, V.; Santoni, C.; Saracino, G.; Sargeni, F.; Semenov, V.; Sergi, A.; Serra, M.; Shaikhiev, A.; Shkarovskiy, S.; Skillicorn, I.; Soldi, D.; Sotnikov, A.; Sougonyaev, V.; Sozzi, M.; Spadaro, T.; Spinella, F.; Staley, R.; Sturgess, A.; Sutcliffe, P.; Szilasi, N.; Tagnani, D.; Trilov, S.; Valdata-Nappi, M.; Valente, P.; Vasile, M.; Vassilieva, T.; Velghe, B.; Veltri, M.; Venditti, S.; Vicini, P.; Volpe, R.; Vormstein, M.; Wahl, H.; Wanke, R.; Wertelaers, P.; Winhart, A.; Winston, R.; Wrona, B.; Yushchenko, O.; Zamkovsky, M.; Zinchenko, A.; NA62 Collaboration

    2017-04-01

    The K+ →π+ ν ν ‾ decay is theoretically one of the cleanest meson decays and so a good place to look for indirect effects of new physics complementary to LHC searches. The NA62 experiment at CERN is designed to measure the branching ratio of this decay with 10% precision. NA62 was commissioned in October 2014, took data in pilot runs in 2014 and 2015. The NA62 experimental setup is illustrated and data quality is reported.

  12. Neutron diffraction studies of the Na-ion battery electrode materials NaCoCr2(PO4)3, NaNiCr2(PO4)3, and Na2Ni2Cr(PO4)3

    NASA Astrophysics Data System (ADS)

    Yahia, H. Ben; Essehli, R.; Avdeev, M.; Park, J.-B.; Sun, Y.-K.; Al-Maadeed, M. A.; Belharouak, I.

    2016-06-01

    The new compounds NaCoCr2(PO4)3, NaNiCr2(PO4)3, and Na2Ni2Cr(PO4)3 were synthesized by sol-gel method and their crystal structures were determined by using neutron powder diffraction data. These compounds were characterized by galvanometric cycling and cyclic voltammetry. NaCoCr2(PO4)3, NaNiCr2(PO4)3, and Na2Ni2Cr(PO4)3 crystallize with a stuffed α-CrPO4-type structure. The structure consists of a 3D-framework made of octahedra and tetrahedra that are sharing corners and/or edges generating channels along [100] and [010], in which the sodium atoms are located. Of significance, in the structures of NaNiCr2(PO4)3, and Na2Ni2Cr(PO4)3 a statistical disorder Ni2+/Cr3+ was observed on both the 8g and 4a atomic positions, whereas in NaCoCr2(PO4)3 the statistical disorder Co2+/Cr3+ was only observed on the 8g atomic position. When tested as negative electrode materials, NaCoCr2(PO4)3, NaNiCr2(PO4)3, and Na2Ni2Cr(PO4)3 delivered specific capacities of 352, 385, and 368 mA h g-1, respectively, which attests to the electrochemical activity of sodium in these compounds.

  13. Magnesium correction to the NaKCa chemical geothermometer

    USGS Publications Warehouse

    Fournier, R.O.; Potter, R.W.

    1979-01-01

    Equations and graphs have been devised to correct for the adverse effects of magnesium upon the Na-K-Ca chemical geothermometer. Either the equations or graphs can be used to determine appropriate temperature corrections for given waters with calculated NaKCa temperatures > 70??C and R 50 are probably derived from relatively cool aquifers with temperatures approximately equal to the measured spring temperature, irrespective of much higher calculated Na-K-Ca temperatures. ?? 1979.

  14. Sodium superionic conduction in Na2B12H12.

    PubMed

    Udovic, Terrence J; Matsuo, Motoaki; Unemoto, Atsushi; Verdal, Nina; Stavila, Vitalie; Skripov, Alexander V; Rush, John J; Takamura, Hitoshi; Orimo, Shin-ichi

    2014-04-11

    Impedance measurements indicate that Na2B12H12 exhibits dramatic Na(+) conductivity (on the order of 0.1 S cm(-1)) above its order-disorder phase-transition at ≈529 K, rivaling that of current, solid-state, ceramic-based, Na-battery electrolytes. Superionicity may be aided by the large size, quasispherical shape, and high rotational mobility of the B12H12(2-) anions.

  15. It reaches remote areas.

    PubMed

    Poppe, P; Aller Atucha, L M

    1992-08-01

    Guatemala's population was 8.2 million according to a 1986-87 survey estimate with a growth rate of 2.8% in the course of the previous 28 years. The current rate was estimated at 3.2%, gross birth rate was 41/1000, and the mortality rate was 9/1000. 1/3 of the population lives in urban areas, and 40% are indigenous ethnic groups. The Integrated Project (IP) was carried out in Solola state in the southwest, a highly productive region with poor health indicators, and lack of safe drinking water, drainage, latrines, and electricity. IP covered a population of 18,600. The Guatemalan Family Welfare Association (APROFAM) in operation since 1965 executed the IP effort. APROFAM has 18 department clinics, 13 medical centers, and 2050 trained voluntary extension workers in addition to doctors, nurses, and auxiliary personnel. The IP effort on control of intestinal parasites was integrated with family planning (FP), and it was launched in 1989 with the school-age population. An evaluation of methodology during 1992-95 was designed to improve IP and consisted of semistructured interviews and informal talks with directors, mayors, female FP users, beneficiaries of parasite control, and focus groups. A baseline study indicated that parasitism was considered dangerous, as there was close to a 90% rate of infection. In 1989 there were only 38 pill users, 161 condom users, and 15 users of vaginal methods. In 1991 there were 222 pill users, 445 condom users, 65 vaginal method users, and 16 persons were referred for sterilization. In 1988 only 6.1% used modern methods, while the current rate increased to 16.6%. The Catholic Church was opposed to IP, there was only fledgling sex education, and the involvement of women and the community was envisioned.

  16. Launch area theodolite system

    NASA Astrophysics Data System (ADS)

    Bradley, Lester M.; Corriveau, John P.; Tindal, Nan E.

    1991-08-01

    White Sands Missile Range has developed a Launch Area Theodolite (LAT) optical tracking system that provides improved Time-Space-Position-Information (TSPI) for the new class of hyper-velocity missiles being developed by the Army. The LAT system consists of a high- performance optical tracking mount equipped with an 8-12 micrometers Forward Looking Infrared (FLIR) sensor, a newly designed full-frame pin-registered 35-mm film camera, and an auto- focused 50-in. focal length lens. The FLIR has been integrated with the WSMR in-house developed statistical based automatic video tracker to yield a powerful system for the automatic tracking of missiles from a short standoff distance. The LAT has been designed to replace large fixed-camera arrays for test programs on short-range anti-tank missiles. New tracking techniques have been developed to deal with angular tracking rates that exceed one radian in both velocity and acceleration. Special techniques have been developed to shock the tracking mount at the missile launch to match the target motion. An adaptive servo control technique allows a Type III servo to be used to compensate for the high angular accelerations that are generated by the placement of the LAT mounts along the missile flight path. An automated mode selection adjustment is employed as the missile passes a point perpendicular to the tracking mount to compensate for the requirement to rapidly decelerate the tracking mount and keep the target in the field-of-view of the data camera. This paper covers the design concept for a network of eight LAT mounts, the techniques of automatic video tracking using a FLIR sensor, and the architecture of the servo control algorithms that have allowed the LAT system to produce results to a degree never before achieved at White Sands Missile Range.

  17. All Conservation Opportunity Areas (ECO.RES.ALL_OP_AREAS)

    EPA Pesticide Factsheets

    The All_OP_Areas GIS layer are all the Conservation Opportunity Areas identified by MoRAP (produced for EPA Region 7). They designate areas with potential for forest, grassland and forest/grassland mosaic conservation. These are areas of natural or semi-natural forest land cover that are at least 75 meters away from roads and away from patch edges. OAs were modeled by creating distance grids using the National Land Cover Database and the Census Bureau's TIGER roads files.

  18. [Syntactic Processing in Broca's Area: Brodmann Areas 44 and 45].

    PubMed

    Yamada, Atora; Sakai, Kuniyoshi L

    2017-04-01

    Brodmann areas 44 and 45 are known as Broca's area; however, their true functional roles are still unknown. Recent developments in neuroimaging techniques revealed the structures and functions of Broca's area in detail. More specifically regarding language functions, sufficient evidence has been accumulated that this region subserves the center of syntactic processing, not necessarily motor functions. Here, we review a role of Broca's area as the grammar center, including other roles in nonlinguistic functions.

  19. All Conservation Opportunity Areas (ECO.RES.ALL_OP_AREAS)

    EPA Pesticide Factsheets

    The All_OP_Areas GIS layer are all the Conservation Opportunity Areas identified by MoRAP (produced for EPA Region 7). They designate areas with potential for forest, grassland and forest/grassland mosaic conservation. These are areas of natural or semi-natural forest land cover that are at least 75 meters away from roads and away from patch edges. OAs were modeled by creating distance grids using the National Land Cover Database and the Census Bureau's TIGER roads files.

  20. HIGHLAND RIDGE ROADLESS AREA, NEVADA.

    USGS Publications Warehouse

    Whitebread, Donald H.; Brown, S. Don

    1984-01-01

    The mineral-resource potential of the Highland Ridge Roadless Area, Nevada was evaluated on the basis of results from field investigations. One area along the west border of the Highland Ridge Roadless Area has substantiated mineral-resource potential for tungsten. Several other areas are classed as having probable mineral-resource potential, based mainly upon anomalously high values of tungsten, lead, silver, and zinc in concentrates of stream sediments. Most of the roadless area is underlain by rocks in the upper plate of the Snake Range decollement, and is considered to have little promise for the occurrence of mineral resources. No energy resource potential was identified in the area.

  1. DRAGOON MOUNTAINS ROADLESS AREA, ARIZONA.

    USGS Publications Warehouse

    Drewes, Harald; Kreidler, T.J.

    1984-01-01

    The mineral and hydrocarbon resource potential of the Dragoon Mountains Roadless Area was assessed and six areas of probable mineral-resource potential were identified. The area may contain metamorphic skarn-type mineralization of copper, lead, molybdenum, and zinc, and some of these may contain silver and gold. More remotely, the area could also contain stockwork molybdenum mineralization and replacement or vein-type mineralization of beryllium, fluorite, thorium, tin, and tungsten. Rock products exist within the area and are discussed due to the proximity of a railroad, but similar materials occur outside the area. There is little promise for the occurrence of energy resources.

  2. Rear Area Security In The Field Army Service Area.

    DTIC Science & Technology

    1965-05-19

    his ma.jor subordinate Commanders, the arm support brigade commander. Rear are? ecurity doctrine requires the area coriander to coordin- ate unit...field army service area. Response The army support brigade coriander conducts phase I rear area security operations within the limits of current

  3. 5 CFR 591.207 - Which areas are COLA areas?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Which areas are COLA areas? 591.207 Section 591.207 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS ALLOWANCES AND DIFFERENTIALS Cost-of-Living Allowance and Post Differential-Nonforeign Areas...

  4. Kinetic properties and Na+ dependence of rheogenic Na(+)-HCO3- co-transport in frog retinal pigment epithelium.

    PubMed Central

    la Cour, M

    1991-01-01

    1. Na(+)-HCO3- co-transport across the retinal membrane of the frog retinal pigment epithelium was studied by means of double-barrelled pH-selective microelectrodes. Transient changes in the intracellular pH were monitored in response to abrupt changes in the Na+ concentration on the retinal side of the epithelium. 2. The experiments were performed as follows. The Na(+)-HCO3- co-transport was inhibited by perfusing the retinal side of the epithelium with a Na(+)-free solution. The co-transport was then stimulated by changing the perfusate from the Na(+)-free solution to a solution which contained from 5 to 110 mM-Na+. The resulting inward Na(+)-HCO3- co-transport produced an intracellular alkalinization, the initial rate of which was used to calculate the initial rate of Na(+)-HCO3- co-transport, JHCO3-. 3. The Na+ dependence of the Na(+)-HCO3- co-transport was studied at two different values of extracellular pH (7.40 and 7.10), at constant extracellular HCO3- concentration (27.5 mM) and at two different extracellular HCO3- concentrations (27.5 mM and 55 mM) at constant extracellular pH (7.40). In these experiments, the calculated values of JHCO3- followed single Michaelis-Menten kinetics with respect to the extracellular Na+ concentration. 4. The data are consistent with a model in which the co-transporter has a single binding site for the Na+ ion with an apparent affinity constant (apparent Km) of 37 mM. The apparent affinity constant for Na+ was independent of the extracellular concentration of CO3(2-) in the range of 16-65 microM, and of the extracellular HCO3- concentration in the range 27.5-55 mM. 5. The NaCO3- ion-pair hypothesis, in which sodium binds to the co-transporter and is translocated across the cell membrane as the NaCO3- ion pair, was analysed. For stoichiometries 1:2 and 1:3 of the Na(+)-HCO3- co-transport, the NaCO3- ion-pair hypothesis was found incompatible with the data. 6. The intracellular buffer capacity as measured by the CO2 method was

  5. Na-22 decay gamma rays from classical novae

    NASA Technical Reports Server (NTRS)

    Truran, James W.

    1993-01-01

    NASA Grant NAG 5-1565 has provided support for a program of theoretical research in nuclear astrophysics and related areas, focusing upon the possibility of detecting gamma rays from nearby novae. Particular attention has been given to the evaluation of the theoretical expectations for gamma ray emission from four possible sources: (1) the positron decays of the unstable CNO and fluorine isotopes that are transported to the surface regions of the envelope in the earliest stages of the outbursts; (2) Be-7 decay gamma rays, (3) Na-22 decay gamma rays released in the later stages of the outbursts; and (4) Al-26 decay gamma rays from novae and their possible contribution to Galactic emission. The critical questions of (1) the frequency of occurrence of ONeMg-enriched novae; (2) the expected Galactic distribution of the novae that produce 26Al; and (3) the nature of the observed soft X-ray emission from classical novae, have also been addressed. Considerable progress in research has been achieved on many of these fronts. Brief summaries of the results of several research projects are presented.

  6. Microstructural evolution in NaNbO3-based antiferroelectrics

    NASA Astrophysics Data System (ADS)

    Guo, Hanzheng; Shimizu, Hiroyuki; Randall, Clive A.

    2015-11-01

    Our recent study found that CaZrO3 doping can effectively enhance the antiferroelectric P phase in NaNbO3 ceramics, leading to a double polarization hysteresis loop characteristic of a reversible antiferroelectric ↔ ferroelectric phase transition [Shimizu et al., Dalton Trans. 44, 10763 (2015)]. Here, a thorough transmission electron microscope study was performed to illustrate the CaZrO3 doping-assisted antiferroelectricity stabilization. In parallel to the bright-field imaging and selected area electron diffraction from multiple zone axes, detailed dark-field imaging was utilized to determine the superlattice structural origins, from either oxygen octahedral tilting or antiparallel cation displacements. By analogy with Pb(Zr1-xTix)O3 and rare-earth doped BiFeO3 systems, the chemical substitutions are such as to an induced polar-to-antipolar transition that is consistent with a tolerance factor reduction. The resultant chemical pressure has a similar effect to the compressive hydrostatic pressure where the antiferroelectric state is favored over the ferroelectric state.

  7. LighSail Students Testing - ELaNa XI

    NASA Image and Video Library

    2014-09-23

    Students Alex Diaz and Riki Munakata of California Polytechnic State University testing the LightSail CubeSat. LightSail is a citizen-funded technology demonstration mission sponsored by the Planetary Society using solar propulsion for CubeSats. The spacecraft is designed to “sail” on the energy of solar photons striking the thin, reflective sail material. The first LightSail mission is designed to test the spacecraft’s critical systems, including the sequence to autonomously deploy a Mylar solar sail with an area of 32 square meters (344 square feet). The Planetary Society is planning a second, full solar sailing demonstration flight for 2016. Light is made of packets of energy called photons. While photons have no mass, they have energy and momentum. Solar sails use this momentum as a method of propulsion, creating flight by light. LightSail’s solar sail is packaged into a three-unit CubeSat about the size of a loaf of bread. Launched by NASA’s CubeSat Launch Initiative on the ELaNa XI mission as an auxiliary payload aboard the U.S. Air Force X-37B space plane mission on May 20, 2015.

  8. Symbiodinium isolation by NaOH treatment.

    PubMed

    Zamoum, Thamilla; Furla, Paola

    2012-11-15

    The presence of photosynthetic zooxanthellae (dinoflagellates) in the tissue of many cnidarians is the main reason for their ecological success (i.e. coral reefs). It could also be the main cause of their demise, as the worldwide bleaching of reef-building coral is nothing less than the breakdown of this symbiotic association. The stability of this relationship is the principal marker for the biomonitoring of cnidarian health. We have therefore developed a new, simple method to isolate zooxanthellae in a few steps using NaOH solution. The protocol was validated in three symbiotic cnidarian species: a sea anemone, a gorgonian and a coral. Our method allows the isolation of intact and viable zooxanthellae with better yields than classic methods, especially for species with a calcareous skeleton. Moreover, the isolated zooxanthellae were free of host nucleic contaminants, facilitating subsequent specific molecular analyses.

  9. The NA49 large acceptance hadron detector

    NASA Astrophysics Data System (ADS)

    Afanasiev, S.; Alber, T.; Appelshäuser, H.; Bächler, J.; Barna, D.; Barnby, L. S.; Bartke, J.; Barton, R. A.; Betev, L.; Bialkowska, H.; Bieser, F.; Billmeier, A.; Blyth, C. O.; Bock, R.; Bormann, C.; Bracinik, J.; Brady, F. P.; Brockmann, R.; Brun, R.; Buncic, P.; Caines, H. L.; Cebra, D.; Cooper, G. E.; Cramer, J. G.; Csato, P.; Cyprian, M.; Dunn, J.; Eckardt, V.; Eckhardt, F.; Empl, T.; Eschke, J.; Ferguson, M. I.; Fessler, H.; Fischer, H. G.; Flierl, D.; Fodor, Z.; Frankenfeld, U.; Foka, P.; Freund, P.; Friese, V.; Ftacnik, J.; Fuchs, M.; Gabler, F.; Gal, J.; Ganz, R.; Gaździcki, M.; Gładysz, E.; Grebieszkow, J.; Günther, J.; Harris, J. W.; Hegyi, S.; Henkel, T.; Hill, L. A.; Hlinka, V.; Huang, I.; Hümmler, H.; Igo, G.; Irmscher, D.; Ivanov, M.; Janik, R.; Jacobs, P.; Jones, P. G.; Kadija, K.; Kolesnikov, V. I.; Kowalski, M.; Lasiuk, B.; Lévai, P.; Liebicher, K.; Lynen, U.; Malakhov, A. I.; Margetis, S.; Markert, C.; Marks, C.; Mayes, B.; Melkumov, G. L.; Mock, A.; Molnár, J.; Nelson, J. M.; Oldenburg, M.; Odyniec, G.; Palla, G.; Panagiotou, A. D.; Pestov, Y.; Petridis, A.; Pikna, M.; Pimpl, W.; Pinsky, L.; Piper, A.; Porter, R. J.; Poskanzer, A. M.; Poziombka, S.; Prindle, D. J.; Pühlhofer, F.; Rauch, W.; Reid, J. G.; Renfordt, R.; Retyk, W.; Ritter, H. G.; Röhrich, D.; Roland, C.; Roland, G.; Rudolph, H.; Rybicki, A.; Sammer, T.; Sandoval, A.; Sann, H.; Schäfer, E.; Schmidt, R.; Schmischke, D.; Schmitz, N.; Schönfelder, S.; Semenov, A. Yu.; Seyboth, J.; Seyboth, P.; Seyerlein, J.; Sikler, F.; Sitar, B.; Skrzypczak, E.; Squier, G. T. A.; Stelzer, H.; Stock, R.; Strmen, P.; Ströbele, H.; Struck, C.; Susa, T.; Szarka, I.; Szentpetery, I.; Szymański, P.; Sziklai, J.; Toy, M.; Trainor, T. A.; Trentalange, S.; Ullrich, T.; Vassiliou, M.; Veres, G.; Vesztergombi, G.; Vranic, D.; Wang, F. Q.; Weerasundara, D. D.; Wenig, S.; Whitten, C.; Wieman, H.; Wienold, T.; Wood, L.; Yates, T. A.; Zimanyi, J.; Zhu, X.-Z.; Zybert, R.

    1999-07-01

    The NA49 detector is a wide acceptance spectrometer for the study of hadron production in p+p, p+A, and A+A collisions at the CERN SPS. The main components are 4 large-volume TPCs for tracking and particle identification via d E/d x. TOF scintillator arrays complement particle identification. Calorimeters for transverse energy determination and triggering, a detector for centrality selection in p+A collisions, and beam definition detectors complete the set-up. A description of all detector components is given with emphasis on new technical realizations. Performance and operational experience are discussed in particular with respect to the high track density environment of central Pb+Pb collisions.

  10. Na-Zn liquid metal battery

    NASA Astrophysics Data System (ADS)

    Xu, Junli; Kjos, Ole Sigmund; Osen, Karen Sende; Martinez, Ana Maria; Kongstein, Ole Edvard; Haarberg, Geir Martin

    2016-11-01

    A new kind of membrane free liquid metal battery was developed. The battery employs liquid sodium and zinc as electrodes both in liquid state, and NaCl-CaCl2 molten salts as electrolyte. The discharge flat voltage is in the range of about 1.4 V-1.8 V, and the cycle efficiency achieved is about 90% at low discharge current densities (below 40 mA cm-2). Moreover, this battery can also be charged and discharged at high current density with good performance. The discharge flat voltage is above 1.1 V when it is discharged at 100 mA cm-2, while it is about 0.8 V with 100% cycle efficiency when it is discharged at 200 mA cm-2. Compared to other reported liquid metal battery, this battery has lower cost, which suggests broad application prospect in energy storage systems for power grid.

  11. Pion and kaon freezeout in NA44

    SciTech Connect

    NA44 Collaboration

    1994-12-01

    The NA44 spectrometer is optimized for the study of single and two-particle particle spectra near mid-rapidity for transverse momenta below {approx} 1 GeV/c. A large fraction of all pairs in the spectrometer`s acceptance are at low relative momenta, resulting in small statistical uncertainties on the extracted size parameters. In addition, the spectrometer`s clean particle identification allows the authors to measure correlation functions for pions, kaons, and protons. This contribution will concentrate on the source size parameters determined from pion and kaon correlation functions. These size parameters will be compared to calculations from the RQMD event generator and also interpreted in the context of a hydrodynamic model. Finally, the measured single particle spectra will be examined from the viewpoint of hydrodynamics.

  12. Study of OSL in NaF: Ca,Cu

    NASA Astrophysics Data System (ADS)

    More, Y. K.; Wankhede, S. P.; Moharil, S. V.

    2013-06-01

    Sodium Fluoride containing Cu+ ions was prepared by R.A.P. followed by melt-quenching technique. Results on photo, thermo and optically stimulated luminescence in NaF:Ca,Cu are reported. OSL sensitivity of NaF:Ca,Cu is approximately 2 times than that of standard phosphor LMP. The rate of OSL depletion for 90% decay for NaF:Ca,Cu is 0.3 times as that of OSL phosphor LMP. NaF:Ca,Cu thus deserves much more attention than it has received up till now.

  13. Influenza virus neuraminidase (NA): a target for antivirals and vaccines.

    PubMed

    Jagadesh, Anitha; Salam, Abdul Ajees Abdul; Mudgal, Piya Paul; Arunkumar, Govindakarnavar

    2016-08-01

    Influenza, the most common infectious disease, poses a great threat to human health because of its highly contagious nature and fast transmissibility, often leading to high morbidity and mortality. Effective vaccination strategies may aid in the prevention and control of recurring epidemics and pandemics associated with this infectious disease. However, antigenic shifts and drifts are major concerns with influenza virus, requiring effective global monitoring and updating of vaccines. Current vaccines are standardized primarily based on the amount of hemagglutinin, a major surface antigen, which chiefly constitutes these preparations along with the varying amounts of neuraminidase (NA). Anti-influenza drugs targeting the active site of NA have been in use for more than a decade now. However, NA has not been approved as an effective antigenic component of the influenza vaccine because of standardization issues. Although some studies have suggested that NA antibodies are able to reduce the severity of the disease and induce a long-term and cross-protective immunity, a few major scientific issues need to be addressed prior to launching NA-based vaccines. Interestingly, an increasing number of studies have shown NA to be a promising target for future influenza vaccines. This review is an attempt to consolidate studies that reflect the strength of NA as a suitable vaccine target. The studies discussed in this article highlight NA as a potential influenza vaccine candidate and support taking the process of developing NA vaccines to the next stage.

  14. The Physiological Relevance of Na+-Coupled K+-Transport.

    PubMed Central

    Maathuis, FJM.; Verlin, D.; Smith, F. A.; Sanders, D.; Fernandez, J. A.; Walker, N. A.

    1996-01-01

    Plant roots utilize at least two distinct pathways with high and low affinities to accumulate K+. The system for high-affinity K+ uptake, which takes place against the electrochemical K+ gradient, requires direct energization. Energization of K+ uptake via Na+ coupling has been observed in algae and was recently proposed as a mechanism for K+ uptake in wheat (Triticum aestivum L.). To investigate whether Na+ coupling has general physiological relevance in energizing K+ transport, we screened a number of species, including Arabidopsis thaliana L. Heynh. ecotype Columbia, wheat, and barley (Hordeum vulgare L.), for the presence of Na+-coupled K+ uptake. Rb+-flux analysis and electrophysiological K+-transport assays were performed in the presence and absence of Na+ and provided evidence for a coupling between K+ and Na+ transport in several aquatic species. However, all investigated terrestrial species were able to sustain growth and K+ uptake in the absence of Na+. Furthermore, the addition of Na+ was either without effect or inhibited K+ absorption. The latter characteristic was independent of growth conditions with respect to Na+ status and pH. Our results suggest that in terrestrial species Na+-coupled K+ transport has no or limited physiological relevance, whereas in certain aquatic angiosperms and algae this type of secondary transport energization plays a significant role. PMID:12226467

  15. New solid conductors of Na/+/ and K/+/ ions

    NASA Technical Reports Server (NTRS)

    Singer, J.; Fielder, W. L.; Kautz, H. E.; Fordyce, J. S.

    1976-01-01

    About 40 structure types for solid conductors of Na(+) and K(+) ions are surveyed. Five compounds in three structure types are discovered to be good solid conductors of alkali metal ions, capable of ion transport with conductivities in the vicinity of 0.00001/ohm-cm at 25 C. These compounds are a bcc form of NaSbO3, an orthorhombic layer structure of the composition 2M2O.3Nb2O5 with M equal to Na or K, and the Na pyrochlores NaTa2O5F and NaTaWO6. Ion exchange is required to produce each of these Na compounds. Only the 2K2O.3Nb2O5 can so far be synthesized directly from the oxides and thus is the only one which can be sintered readily. The niobate is about as good a conductor of K(+) ion as is K-beta alumina. The NaSbO3 compares well with Na beta at 280 C. A number of phase diagrams are developed.

  16. New solid conductors of Na/+/ and K/+/ ions

    NASA Technical Reports Server (NTRS)

    Singer, J.; Fielder, W. L.; Kautz, H. E.; Fordyce, J. S.

    1976-01-01

    About 40 structure types for solid conductors of Na(+) and K(+) ions are surveyed. Five compounds in three structure types are discovered to be good solid conductors of alkali metal ions, capable of ion transport with conductivities in the vicinity of 0.00001/ohm-cm at 25 C. These compounds are a bcc form of NaSbO3, an orthorhombic layer structure of the composition 2M2O.3Nb2O5 with M equal to Na or K, and the Na pyrochlores NaTa2O5F and NaTaWO6. Ion exchange is required to produce each of these Na compounds. Only the 2K2O.3Nb2O5 can so far be synthesized directly from the oxides and thus is the only one which can be sintered readily. The niobate is about as good a conductor of K(+) ion as is K-beta alumina. The NaSbO3 compares well with Na beta at 280 C. A number of phase diagrams are developed.

  17. Kaolin-based geopolymers with various NaOH concentrations

    NASA Astrophysics Data System (ADS)

    Heah, C. Y.; Kamarudin, H.; Mustafa Al Bakri, A. M.; Bnhussain, M.; Luqman, M.; Khairul Nizar, I.; Ruzaidi, C. M.; Liew, Y. M.

    2013-03-01

    Kaolin geopolymers were produced by the alkali-activation of kaolin with an activator solution (a mixture of NaOH and sodium silicate solutions). The NaOH solution was prepared at a concentration of 6-14 mol/L and was mixed with the sodium silicate solution at a Na2SiO3/NaOH mass ratio of 0.24 to prepare an activator solution. The kaolin-to-activator solution mass ratio used was 0.80. This paper aimed to analyze the effect of NaOH concentration on the compressive strength of kaolin geopolymers at 80°C for 1, 2, and 3 d. Kaolin geopolymers were stable in water, and strength results showed that the kaolin binder had adequate compressive strength with 12 mol/L of NaOH concentration. When the NaOH concentration increased, the SiO2/Na2O decreased. The increased Na2O content enhanced the dissolution of kaolin as shown in X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses. However, excess in this content was not beneficial for the strength development of kaolin geopolymers. In addition, there was the formation of more geopolymeric gel in 12 mol/L samples. The XRD pattern of the samples showed a higher amorphous content and a more geopolymer bonding existed as proved by FTIR analysis.

  18. Tuning NaYF4 Nanoparticles through Alkaline Earth Doping

    PubMed Central

    Chen, Xian; Peng, Dengfeng; Wang, Feng

    2013-01-01

    Phase and size of lanthanide-doped nanoparticles are the most important characteristics that dictate optical properties of these nanoparticles and affect their technological applications. Herein, we present a systematic study to examine the effect of alkaline earth doping on the formation of NaYF4 upconversion nanoparticles. We show that alkaline earth doping has a dual function of tuning particle size of hexagonal phase NaYF4 nanoparticles and stabilizing cubic phase NaYF4 nanoparticles depending on composition and concentration of the dopant ions. The study described here represents a facile and general strategy to tuning the properties of NaYF4 upconversion nanoparticles. PMID:28348353

  19. Transcriptional regulators of Na,K-ATPase subunits

    PubMed Central

    Li, Zhiqin; Langhans, Sigrid A.

    2015-01-01

    The Na,K-ATPase classically serves as an ion pump creating an electrochemical gradient across the plasma membrane that is essential for transepithelial transport, nutrient uptake and membrane potential. In addition, Na,K-ATPase also functions as a receptor, a signal transducer and a cell adhesion molecule. With such diverse roles, it is understandable that the Na,K-ATPase subunits, the catalytic α-subunit, the β-subunit and the FXYD proteins, are controlled extensively during development and to accommodate physiological needs. The spatial and temporal expression of Na,K-ATPase is partially regulated at the transcriptional level. Numerous transcription factors, hormones, growth factors, lipids, and extracellular stimuli modulate the transcription of the Na,K-ATPase subunits. Moreover, epigenetic mechanisms also contribute to the regulation of Na,K-ATPase expression. With the ever growing knowledge about diseases associated with the malfunction of Na,K-ATPase, this review aims at summarizing the best-characterized transcription regulators that modulate Na,K-ATPase subunit levels. As abnormal expression of Na,K-ATPase subunits has been observed in many carcinoma, we will also discuss transcription factors that are associated with epithelial-mesenchymal transition, a crucial step in the progression of many tumors to malignant disease. PMID:26579519

  20. Mercury's Na Exosphere from MESSENGER Data

    NASA Technical Reports Server (NTRS)

    Killen, Rosemary M.; Burger, M. H.; Cassidy, T. A.; Sarantos, M.; Vervack, R. J.; McClintock, W. El; Merkel, A. W.; Sprague, A. L.; Solomon, S. C.

    2012-01-01

    MESSENGER entered orbit about Mercury on March 18, 2011. Since then, the Ultraviolet and Visible Spectrometer (UWS) channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer (MASCS) has been observing Mercury's exosphere nearly continuously. Daily measurements of Na brightness were fitted with non-uniform exospheric models. With Monte Carlo sampling we traced the trajectories of a representative number of test particles, generally one million per run per source process, until photoionization, escape from the gravitational well, or permanent sticking at the surface removed the atom from the simulation. Atoms were assumed to partially thermally accommodate on each encounter with the surface with accommodation coefficient 0.25. Runs for different assumed source processes are run separately, scaled and co-added. Once these model results were saved onto a 3D grid, we ran lines of sight from the MESSENGER spacecraft :0 infinity using the SPICE kernels and we computed brightness integrals. Note that only particles that contribute to the measurement can be constrained with our method. Atoms and molecules produced on the nightside must escape the shadow in order to scatter light if the excitation process is resonant-light scattering, as assumed here. The aggregate distribution of Na atoms fits a 1200 K gas, with a PSD distribution, along with a hotter component. Our models constrain the hot component, assumed to be impact vaporization, to be emitted with a 2500 K Maxwellian. Most orbits show a dawnside enhancement in the hot component broadly spread over the leading hemisphere. However, on some dates there is no dawn/dusk asymmetry. The portion of the hot/cold source appears to be highly variable.

  1. Mercury's Na Exosphere from MESSENGER Data

    NASA Technical Reports Server (NTRS)

    Killen, Rosemary M.; Burger, M. H.; Cassidy, T. A.; Sarantos, M.; Vervack, R. J.; McClintock, W. El; Merkel, A. W.; Sprague, A. L.; Solomon, S. C.

    2012-01-01

    MESSENGER entered orbit about Mercury on March 18, 2011. Since then, the Ultraviolet and Visible Spectrometer (UWS) channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer (MASCS) has been observing Mercury's exosphere nearly continuously. Daily measurements of Na brightness were fitted with non-uniform exospheric models. With Monte Carlo sampling we traced the trajectories of a representative number of test particles, generally one million per run per source process, until photoionization, escape from the gravitational well, or permanent sticking at the surface removed the atom from the simulation. Atoms were assumed to partially thermally accommodate on each encounter with the surface with accommodation coefficient 0.25. Runs for different assumed source processes are run separately, scaled and co-added. Once these model results were saved onto a 3D grid, we ran lines of sight from the MESSENGER spacecraft :0 infinity using the SPICE kernels and we computed brightness integrals. Note that only particles that contribute to the measurement can be constrained with our method. Atoms and molecules produced on the nightside must escape the shadow in order to scatter light if the excitation process is resonant-light scattering, as assumed here. The aggregate distribution of Na atoms fits a 1200 K gas, with a PSD distribution, along with a hotter component. Our models constrain the hot component, assumed to be impact vaporization, to be emitted with a 2500 K Maxwellian. Most orbits show a dawnside enhancement in the hot component broadly spread over the leading hemisphere. However, on some dates there is no dawn/dusk asymmetry. The portion of the hot/cold source appears to be highly variable.

  2. Mercury's Na Exosphere from MESSENGER data

    NASA Astrophysics Data System (ADS)

    Killen, Rosemary M.; Burger, M. H.; Cassidy, T. A.; Sarantos, M.; Vervack, R. J.; McClintock, W. E.; Merkel, A. W.; Sprague, A. L.; Solomon, S. C.

    2012-10-01

    MESSENGER entered orbit about Mercury on March 18, 2011. Since then, the Ultraviolet and Visible Spectrometer (UVVS) channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer (MASCS) has been observing Mercury's exosphere nearly continuously. Daily measurements of Na brightness were fitted with non-uniform exospheric models. With Monte Carlo sampling we traced the trajectories of a representative number of test particles, generally one million per run per source process, until photoionization, escape from the gravitational well, or permanent sticking at the surface removed the atom from the simulation. Atoms were assumed to partially thermally accommodate on each encounter with the surface with accommodation coefficient 0.25. Runs for different assumed source processes are run separately, scaled and co-added. Once these model results were saved onto a 3D grid, we ran lines of sight from the MESSENGER spacecraft to infinity using the SPICE kernels and we computed brightness integrals. Note that only particles that contribute to the measurement can be constrained with our method. Atoms and molecules produced on the nightside must escape the shadow in order to scatter light if the excitation process is resonant-light scattering, as assumed here. The aggregate distribution of Na atoms fits a 1200 K gas, with a PSD distribution, along with a hotter component. Our models constrain the hot component, assumed to be impact vaporization, to be emitted with a 2500 K Maxwellian. Most orbits show a dawnside enhancement in the hot component broadly spread over the leading hemisphere. However, on some dates there is no dawn/dusk asymmetry. The hot portion of the source appears to be highly variable. The authors acknowledge support from NASA through the MESSENGER Participating Scientist Program and Planetary Atmospheres research grants.

  3. Integration between the lateral preoptic area and subfornical organ in the regulation of water intake and hemodynamics in the rat.

    PubMed

    Saad, W A; Camargo, L A; Menani, J V; Renzi, A; Saad, W A

    1987-01-01

    1. The injection of a hypertonic saline solution (0.2 M NaCl) into the lateral preoptic area of the rat produced an increase in water intake that was further increased by the injection of angiotensin II (4 ng) into the subfornical organ. An increase in arterial pressure was also observed. Increase in heart rate was noted after injection of 0.2 M NaCl into the lateral preoptic area. 2. The injection of hypertonic NaCl into the subfornical organ increased water intake and the injection of 4 ng of angiotensin II into the lateral preoptic area augmented this effect. The injection of 0.2 M NaCl into the subfornical organ did not affect blood pressure or heart rate, whereas the injection of angiotensin II into the lateral preoptic area resulted in an increase in these parameters. 3. Intravenous perfusion of angiotensin II (40 ng microliters-1 min-1) caused increased water intake, arterial pressure and heart rate. Dehydration of the lateral preoptic area by 0.2 M NaCl resulted in a summation of effects for water intake alone. 4. Intravenous perfusion with 0.5 M NaCl caused an increase in water intake which was further increased after the injection of angiotensin II (4 ng) into the subfornical organ and angiotensin II (4 ng) into the lateral preoptic area. Arterial pressure and heart rate also increased, remaining unchanged when angiotensin II was injected into the subfornical organ or into the lateral preoptic area. 5. These results suggest interactions between the two areas in the regulation of cardiovascular and thirst mechanisms. However, cardiovascular regulation and the regulation of body fluids may be stimulated by physiological responses to separate mechanisms.

  4. Scintillation efficiency measurement of Na recoils in NaI(Tl) below the DAMA/LIBRA energy threshold

    NASA Astrophysics Data System (ADS)

    Xu, Jingke; Shields, Emily; Calaprice, Frank; Westerdale, Shawn; Froborg, Francis; Suerfu, Burkhant; Alexander, Thomas; Aprahamian, Ani; Back, Henning O.; Casarella, Clark; Fang, Xiao; Gupta, Yogesh K.; Ianni, Aldo; Lamere, Edward; Lippincott, W. Hugh; Liu, Qian; Lyons, Stephanie; Siegl, Kevin; Smith, Mallory; Tan, Wanpeng; Kolk, Bryant Vande

    2015-07-01

    The dark matter interpretation of the DAMA modulation signal depends on the NaI(Tl) scintillation efficiency of nuclear recoils. Previous measurements for Na recoils have large discrepancies, especially in the DAMA/LIBRA modulation energy region. We report a quenching effect measurement of Na recoils in NaI(Tl) from 3 to 52 keVnr, covering the whole DAMA/LIBRA energy region for dark matter-Na scattering interpretations. By using a low-energy, pulsed neutron beam, a double time-of-flight technique, and pulse-shape discrimination methods, we obtained the most accurate measurement of this kind for NaI(Tl) to date. The results differ significantly from the DAMA reported values at low energies but fall between the other previous measurements. We present the implications of the new quenching results for the dark matter interpretation of the DAMA modulation signal.

  5. Attenuation of Na/K-ATPase Mediated Oxidant Amplification with pNaKtide Ameliorates Experimental Uremic Cardiomyopathy

    PubMed Central

    Liu, Jiang; Tian, Jiang; Chaudhry, Muhammad; Maxwell, Kyle; Yan, Yanling; Wang, Xiaoliang; Shah, Preeya T.; Khawaja, Asad A.; Martin, Rebecca; Robinette, Tylor J.; El-Hamdani, Adee; Dodrill, Michael W.; Sodhi, Komal; Drummond, Christopher A.; Haller, Steven T.; Kennedy, David J.; Abraham, Nader G.; Xie, Zijian; Shapiro, Joseph I.

    2016-01-01

    We have previously reported that the sodium potassium adenosine triphosphatase (Na/K-ATPase) can effect the amplification of reactive oxygen species. In this study, we examined whether attenuation of oxidant stress by antagonism of Na/K-ATPase oxidant amplification might ameliorate experimental uremic cardiomyopathy induced by partial nephrectomy (PNx). PNx induced the development of cardiac morphological and biochemical changes consistent with human uremic cardiomyopathy. Both inhibition of Na/K-ATPase oxidant amplification with pNaKtide and induction of heme oxygenase-1 (HO-1) with cobalt protoporphyrin (CoPP) markedly attenuated the development of phenotypical features of uremic cardiomyopathy. In a reversal study, administration of pNaKtide after the induction of uremic cardiomyopathy reversed many of the phenotypical features. Attenuation of Na/K-ATPase oxidant amplification may be a potential strategy for clinical therapy of this disorder. PMID:27698370

  6. Scintillation Efficiency Measurement of Na Recoils in NaI(Tl) Below the DAMA/LIBRA Energy Threshold

    SciTech Connect

    Xu, Jingke; Shields, Emily; Calaprice, Frank; Westerdale, Shawn; Froborg, Francis; Suerfu, Burkhant; Alexander, Thomas; Aprahamian, Ani; Back, Henning O.; Casarella, Clark; Fang, Xiao; Gupta, Yogesh K.; Ianni, Aldo; Lamere, Edward; Lippincott, W. Hugh; Liu, Qian; Lyons, Stephanie; Siegl, Kevin; Smith, Mallory; Tan, Wanpeng; Kolk, Bryant Vande

    2015-07-30

    The dark matter interpretation of the DAMA modulation signal depends on the NaI(Tl) scintillation efficiency of nuclear recoils. Previous measurements for Na recoils have large discrepancies, especially in the DAMA/LIBRA modulation energy region. We report a quenching effect measurement of Na recoils in NaI(Tl) from 3 to 52 keVnr, covering the whole DAMA/LIBRA energy region for dark matter-Na scattering interpretations. By using a low-energy, pulsed neutron beam, a double time-of-flight technique, and pulse-shape discrimination methods, we obtained the most accurate measurement of this kind for NaI(Tl) to date. The results differ significantly from the DAMA reported values at low energies but fall between the other previous measurements. We present the implications of the new quenching results for the dark matter interpretation of the DAMA modulation signal.

  7. Na/K Pump and Beyond: Na/K-ATPase as a Modulator of Apoptosis and Autophagy.

    PubMed

    Felippe Gonçalves-de-Albuquerque, Cassiano; Ribeiro Silva, Adriana; Ignácio da Silva, Camila; Caire Castro-Faria-Neto, Hugo; Burth, Patrícia

    2017-04-21

    Lung cancer is a leading cause of global cancer deaths. Na/K-ATPase has been studied as a target for cancer treatment. Cardiotonic steroids (CS) trigger intracellular signalling upon binding to Na/K-ATPase. Normal lung and tumour cells frequently express different pump isoforms. Thus, Na/K-ATPase is a powerful target for lung cancer treatment. Drugs targeting Na/K-ATPase may induce apoptosis and autophagy in transformed cells. We argue that Na/K-ATPase has a role as a potential target in chemotherapy in lung cancer treatment. We discuss the effects of Na/K-ATPase ligands and molecular pathways inducing deleterious effects on lung cancer cells, especially those leading to apoptosis and autophagy.

  8. Decomposition reactions for NaAl H4 , Na3 Al H6 , and NaH: First-principles study

    NASA Astrophysics Data System (ADS)

    Ke, Xuezhi; Tanaka, Isao

    2005-01-01

    The electronic properties and lattice dynamics of the sodium alanate phases have been studied by the density functional calculations. The phases include NaAlH4 (space group, I41/a ), Na3AlH6 (space group, P21/n ), and NaH (space group, Fm-3m ). The electronic properties are discussed on the basis of the electronic band structures, the atomic charges, the bond overlap population analysis, and the Born effective charges. The phonon dispersion relations and phonon density of states (DOS) of the phases are calculated by a direct force-constant method. Within the quasiharmonic approximation, the calculated thermodynamic functions including the heat capacity, the vibrational enthalpy, and the vibrational entropy are in good agreement with experimental values. Three decomposition reactions are studied based on the thermodynamic functions. The reactions are (1) NaAlH4→(1)/(3)Na3AlH6+(2)/(3)Al+H2 , (2) (1)/(3)Na3AlH6→NaH+(1)/(3)Al+(1)/(2)H2 , and (3) NaH→Na+(1)/(2)H2 . The reactions (1), (2), and (3) are predicted to take place at 285, 390, and 726K , respectively, which are in good agreement with the experiment (353, 423, and 698K , respectively). The individual contributions to the reactions including the enthalpy and entropy are investigated. We found that the enthalpy for the reaction is almost constant, and the net entropy contribution ( TΔS ) to the reaction is approximately equal to the entropy contribution of the H2 gas molecule (produced in that reaction).

  9. Interface Induced Growth and Transformation of Polymer-Conjugated Proto-Crystalline Phases in Aluminosilicate Hybrids: A Multiple-Quantum (23)Na-(23)Na MAS NMR Correlation Spectroscopy Study.

    PubMed

    Brus, Jiri; Kobera, Libor; Urbanova, Martina; Doušová, Barbora; Lhotka, Miloslav; Koloušek, David; Kotek, Jiří; Čuba, Pavel; Czernek, Jiri; Dědeček, Jiří

    2016-03-22

    Nanostructured materials typically offer enhanced physicochemical properties because of their large interfacial area. In this contribution, we present a comprehensive structural characterization of aluminosilicate hybrids with polymer-conjugated nanosized zeolites specifically grown at the organic-inorganic interface. The inorganic amorphous Al-O-Si framework is formed by alkali-activated low-temperature transformation of metakaoline, whereas simultaneous copolymerization of organic comonomers creates a secondary epoxide network covalently bound to the aluminosilicate matrix. This secondary epoxide phase not only enhances the mechanical integrity of the resulting hybrids but also introduces additional binding sites accessible for compensating negative charge on the aluminosilicate framework. This way, the polymer network initiates growth and subsequent transformation of protocrystalline short-range ordered zeolite domains that are located at the organic-inorganic interface. By applying an experimental approach based on 2D (23)Na-(23)Na double-quantum (DQ) MAS NMR spectroscopy, we discovered multiple sodium binding sites in these protocrystalline domains, in which immobilized Na(+) ions form pairs or small clusters. It is further demonstrated that these sites, the local geometry of which allows for the pairing of sodium ions, are preferentially occupied by Pb(2+) ions during the ion exchange. The proposed synthesis protocol thus allows for the preparation of a novel type of geopolymer hybrids with polymer-conjugated zeolite phases suitable for capturing and storage of metal cations. The demonstrated (23)Na-(23)Na DQ MAS NMR combined with DFT calculations represents a suitable approach for understanding the role of Na(+) ions in aluminositicate solids and related inorganic-organic hybrids, particularly their specific arrangement and clustering at interfacial areas.

  10. Phase equilibria in system LiCl-NaCl-H2O at 308 and 348 K

    NASA Astrophysics Data System (ADS)

    Wang, Shi-qiang; Guo, Ya-fei; Liu, Dong-fang; Deng, Tian-long

    2016-12-01

    The solubilities and densities of the solutions in the ternary system LiCl-NaCl-H2O at 308 and 348 K were determined by the method of isothermal dissolution equilibrium. There are one invariant point, two univariant isotherm dissolution curves, and two crystallization regions corresponding to monohydrate (LiCl · H2O) and NaCl, respectively. This system at both temperatures belongs to hydrate type I, and neither double salt nor solid solution was found. A comparison of the phase diagram for the ternary system at 273-348 K shows that the area of crystallization region of LiCl · H2O is decreased with the increasing of temperature, while that of NaCl is increased obviously. The solution density of the ternary system at two temperatures changes regularly with the increasing of LiCl concentration.

  11. Hollow Sodium Tungsten Bronze (Na0.15WO3) Nanospheres: Preparation, Characterization, and Their Adsorption Properties.

    PubMed

    Hou, Jing; Zuo, Guanke; Shen, Guangxia; Guo, He; Liu, Hui; Cheng, Ping; Zhang, Jingyan; Guo, Shouwu

    2009-07-17

    We report herein a facile method for the preparation of sodium tungsten bronzes hollow nanospheres using hydrogen gas bubbles as reactant for chemical reduction of tungstate to tungsten and as template for the formation of hollow nanospheres at the same time. The chemical composition and the crystalline state of the as-prepared hollow Na0.15WO3nanospheres were characterized complementarily, and the hollow structure formation mechanism was proposed. The hollow Na0.15WO3nanospheres showed large Brunauer-Emment-Teller specific area (33.8 m2 g-1), strong resistance to acids, and excellent ability to remove organic molecules such as dye and proteins from aqueous solutions. These illustrate that the hollow nanospheres of Na0.15WO3should be a useful adsorbent.

  12. Lack of combination hepatocarcinogenicity of harman, norharman and amitrole when given with NaNO2 in the rat.

    PubMed

    Ichihara, Toshio; Miyashita, Kayoko; Kawabe, Mayumi; Imaida, Katsumi; Asamoto, Makoto; Ogiso, Tadashi; Tamano, Seiko; Hirose, Masao; Shirai, Tomoyuki

    2005-02-01

    N-nitrosocompounds, which induce cancers in various organs, may be formed endogenously with intake of amino compounds such as secondary amines and sodium nitrite (NaNO(2)) in combination. The present study was performed to investigate whether three amino compounds, 1-methyl-9H-pyrido[3,4-b]indole (harman), 9H-pyrido[3,4-b]indole (norharman) and 2-amino-1,3,4-triazole (amitrole), might be converted in vivo to compounds capable of promoting hepatocarcinogenesis when given with NaNO(2). However, in an 8-week model, no modifying potential was evident in terms of numbers and areas of putative preneoplastic glutathione S-transferase placental form (GST-P)-positive foci in any of the groups receiving paired treatments. These results demonstrate that combinations of harman, norharman and amitrole with NaNO(2) lack promoting effects for liver carcinogenesis in our medium-term bioassay system.

  13. Hollow Sodium Tungsten Bronze (Na0.15WO3) Nanospheres: Preparation, Characterization, and Their Adsorption Properties

    PubMed Central

    2009-01-01

    We report herein a facile method for the preparation of sodium tungsten bronzes hollow nanospheres using hydrogen gas bubbles as reactant for chemical reduction of tungstate to tungsten and as template for the formation of hollow nanospheres at the same time. The chemical composition and the crystalline state of the as-prepared hollow Na0.15WO3nanospheres were characterized complementarily, and the hollow structure formation mechanism was proposed. The hollow Na0.15WO3nanospheres showed large Brunauer–Emment–Teller specific area (33.8 m2 g−1), strong resistance to acids, and excellent ability to remove organic molecules such as dye and proteins from aqueous solutions. These illustrate that the hollow nanospheres of Na0.15WO3should be a useful adsorbent. PMID:20596394

  14. Novel band gap-tunable K-Na co-doped graphitic carbon nitride prepared by molten salt method

    NASA Astrophysics Data System (ADS)

    Zhao, Jiannan; Ma, Lin; Wang, Haoying; Zhao, Yanfeng; Zhang, Jian; Hu, Shaozheng

    2015-03-01

    Novel band gap-tunable K-Na co-doped graphitic carbon nitride was prepared by molten salt method using melamine, KCl, and NaCl as precursor. X-ray diffraction (XRD), N2 adsorption, Scanning electron microscope (SEM), UV-vis spectroscopy, Photoluminescence (PL), and X-ray photoelectron spectroscopy (XPS) were used to characterize the prepared catalysts. The CB and VB potentials of graphitic carbon nitride could be tuned from -1.09 and +1.55 eV to -0.29 and +2.25 eV by controlling the weight ratio of eutectic salts to melamine. Besides, ions doping inhibited the crystal growth of graphitic carbon nitride, enhanced the surface area, and increased the separation rate of photogenerated electrons and holes. The visible-light-driven Rhodamine B (RhB) photodegradation and mineralization performances were significantly improved after K-Na co-doping.

  15. STUDY AREAS CONTIGUOUS TO THE UNCOMPAHGRE PRIMITIVE AREA, COLORADO.

    USGS Publications Warehouse

    Steven, Thomas A.; Bieniewski, Carl L.

    1984-01-01

    Important mineral deposits of several ages have been exploited at many places in the western San Juan Mountains, including the originally studied Uncompahgre Primitive Area, Colorado. Although the three contiguous areas - western, central, and eastern - considered here are largely outside the more productive mining areas, a mineral study indicated that there are areas of probable resource potential for base and precious metals near the margins of the areas. Results of this study indicate that there is little promise for the occurrence of fossil fuels and geothermal energy.

  16. Facial Areas and Emotional Information

    ERIC Educational Resources Information Center

    Boucher, Jerry D.; Ekman, Paul

    1975-01-01

    Provides strong support for the view that there is no one area of the face which best reveals emotion, but that the value of the different facial areas in distinguishing emotions depends upon the emotion being judged. (Author)

  17. Facial Areas and Emotional Information

    ERIC Educational Resources Information Center

    Boucher, Jerry D.; Ekman, Paul

    1975-01-01

    Provides strong support for the view that there is no one area of the face which best reveals emotion, but that the value of the different facial areas in distinguishing emotions depends upon the emotion being judged. (Author)

  18. RNA adducts with Na 2SeO 4 and Na 2SeO 3 - Stability and structural features

    NASA Astrophysics Data System (ADS)

    Nafisi, Shohreh; Manouchehri, Firouzeh; Montazeri, Maryam

    2011-12-01

    Selenium compounds are widely available in dietary supplements and have been extensively studied for their antioxidant and anticancer properties. Low blood Se levels were found to be associated with an increased incidence and mortality from various types of cancers. Although many in vivo and clinical trials have been conducted using these compounds, their biochemical and chemical mechanisms of efficacy are the focus of much current research. This study was designed to examine the interaction of Na 2SeO 4 and Na 2SeO 3 with RNA in aqueous solution at physiological conditions, using a constant RNA concentration (6.25 mM) and various sodium selenate and sodium selenite/polynucleotide (phosphate) ratios of 1/80, 1/40, 1/20, 1/10, 1/5, 1/2 and 1/1. Fourier transform infrared, UV-Visible spectroscopic methods were used to determine the drug binding modes, the binding constants, and the stability of Na 2SeO 4 and Na 2SeO 3-RNA complexes in aqueous solution. Spectroscopic evidence showed that Na 2SeO 4 and Na 2SeO 3 bind to the major and minor grooves of RNA ( via G, A and U bases) with some degree of the Se-phosphate (PO 2) interaction for both compounds with overall binding constants of K(Na 2SeO 4-RNA) = 8.34 × 10 3 and K(Na 2SeO 3-RNA) = 4.57 × 10 3 M -1. The order of selenium salts-biopolymer stability was Na 2SeO 4-RNA > Na 2SeO 3-RNA. RNA aggregations occurred at higher selenium concentrations. No biopolymer conformational changes were observed upon Na 2SeO 4 and Na 2SeO 3 interactions, while RNA remains in the A-family structure.

  19. Mechanism of μ-conotoxin PIIIA binding to the voltage-gated Na+ channel NaV1.4.

    PubMed

    Chen, Rong; Robinson, Anna; Chung, Shin-Ho

    2014-01-01

    Several subtypes of voltage-gated Na+ (NaV) channels are important targets for pain management. μ-Conotoxins isolated from venoms of cone snails are potent and specific blockers of different NaV channel isoforms. The inhibitory effect of μ-conotoxins on NaV channels has been examined extensively, but the mechanism of toxin specificity has not been understood in detail. Here the known structure of μ-conotoxin PIIIA and a model of the skeletal muscle channel NaV1.4 are used to elucidate elements that contribute to the structural basis of μ-conotoxin binding and specificity. The model of NaV1.4 is constructed based on the crystal structure of the bacterial NaV channel, NaVAb. Six different binding modes, in which the side chain of each of the basic residues carried by the toxin protrudes into the selectivity filter of NaV1.4, are examined in atomic detail using molecular dynamics simulations with explicit solvent. The dissociation constants (Kd) computed for two selected binding modes in which Lys9 or Arg14 from the toxin protrudes into the filter of the channel are within 2 fold; both values in close proximity to those determined from dose response data for the block of NaV currents. To explore the mechanism of PIIIA specificity, a double mutant of NaV1.4 mimicking NaV channels resistant to μ-conotoxins and tetrodotoxin is constructed and the binding of PIIIA to this mutant channel examined. The double mutation causes the affinity of PIIIA to reduce by two orders of magnitude.

  20. A 23Na magic angle spinning nuclear magnetic resonance, XANES, and high-temperature X-ray diffraction study of NaUO3, Na4UO5, and Na2U2O7.

    PubMed

    Smith, A L; Raison, P E; Martel, L; Charpentier, T; Farnan, I; Prieur, D; Hennig, C; Scheinost, A C; Konings, R J M; Cheetham, A K

    2014-01-06

    The valence state of uranium has been confirmed for the three sodium uranates NaU(V)O3/[Rn](5f(1)), Na4U(VI)O5/[Rn](5f(0)), and Na2U(VI)2O7/[Rn](5f(0)), using X-ray absorption near-edge structure (XANES) spectroscopy. Solid-state (23)Na magic angle spinning nuclear magnetic resonance (MAS NMR) measurements have been performed for the first time, yielding chemical shifts at -29.1 (NaUO3), 15.1 (Na4UO5), and -14.1 and -19 ppm (Na1 8-fold coordinated and Na2 7-fold coordinated in Na2U2O7), respectively. The [Rn]5f(1) electronic structure of uranium in NaUO3 causes a paramagnetic shift in comparison to Na4UO5 and Na2U2O7, where the electronic structure is [Rn]5f(0). A (23)Na multi quantum magic angle spinning (MQMAS) study on Na2U2O7 has confirmed a monoclinic rather than rhombohedral structure with evidence for two distinct Na sites. DFT calculations of the NMR parameters on the nonmagnetic compounds Na4UO5 and Na2U2O7 have permitted the differentiation between the two Na sites of the Na2U2O7 structure. The linear thermal expansion coefficients of all three compounds have been determined using high-temperature X-ray diffraction: αa = 22.7 × 10(-6) K(-1), αb = 12.9 × 10(-6) K(-1), αc = 16.2 × 10(-6) K(-1), and αvol = 52.8 × 10(-6) K(-1) for NaUO3 in the range 298-1273 K; αa = 37.1 × 10(-6) K(-1), αc = 6.2 × 10(-6) K(-1), and αvol = 81.8 × 10(-6) K(-1) for Na4UO5 in the range 298-1073 K; αa = 6.7 × 10(-6) K(-1), αb = 14.4 × 10(-6) K(-1), αc = 26.8 × 10(-6) K(-1), αβ = -7.8 × 10(-6) K(-1), and αvol = -217.6 × 10(-6) K(-1) for Na2U2O7 in the range 298-573 K. The α to β phase transition reported for the last compound above about 600 K was not observed in the present studies, either by high-temperature X-ray diffraction or by differential scanning calorimetry.